BGP redesign

Integrated and extensible BGP with generalized AFI handling,
support for IPv4+IPv6 AFI and unicast+multicast SAFI.

6 files changed, 4011 insertions, 3179 deletions

diff --git a/proto/bgp/attrs.c b/proto/bgp/attrs.c
index 0309c1f7..52b56efa 100644
--- a/proto/bgp/attrs.c
+++ b/proto/bgp/attrs.c
@@ -2,6 +2,8 @@
  *	BIRD -- BGP Attributes
  *
  *	(c) 2000 Martin Mares <mj@ucw.cz>
+ *	(c) 2008--2016 Ondrej Zajicek <santiago@crfreenet.org>
+ *	(c) 2008--2016 CZ.NIC z.s.p.o.
  *
  *	Can be freely distributed and used under the terms of the GNU GPL.
  */
@@ -56,869 +58,1157 @@
  * inconsistencies between AGGREGATOR and AS4_AGGREGATOR that are not
  * handled by that draft, these are logged and ignored (see
  * bgp_reconstruct_4b_attrs()).
+ *
+ * BGP attribute table has several hooks:
+ *
+ * export - Hook that validates and normalizes attribute during export phase.
+ * Receives eattr, may modify it (e.g., sort community lists for canonical
+ * representation), UNSET() it (e.g., skip empty lists), or WITHDRAW() it if
+ * necessary. May assume that eattr has value valid w.r.t. its type, but may be
+ * invalid w.r.t. BGP constraints. Optional.
+ *
+ * encode - Hook that converts internal representation to external one during
+ * packet writing. Receives eattr and puts it in the buffer (including attribute
+ * header). Returns number of bytes, or -1 if not enough space. May assume that
+ * eattr has value valid w.r.t. its type and validated by export hook. Mandatory
+ * for all known attributes that exist internally after export phase (i.e., all
+ * except pseudoattributes MP_(UN)REACH_NLRI).
+ *
+ * decode - Hook that converts external representation to internal one during
+ * packet parsing. Receives attribute data in buffer, validates it and adds
+ * attribute to ea_list. If data are invalid, steps DISCARD(), WITHDRAW() or
+ * bgp_parse_error() may be used to escape. Mandatory for all known attributes.
+ *
+ * format - Optional hook that converts eattr to textual representation.
  */
 
+// XXXX review pool usage : c->c.proto->pool
 
-static byte bgp_mandatory_attrs[] = { BA_ORIGIN, BA_AS_PATH
-#ifndef IPV6
-,BA_NEXT_HOP
-#endif
-};
 
-struct attr_desc {
-  char *name;
-  int expected_length;
-  int expected_flags;
-  int type;
-  int allow_in_ebgp;
-  int (*validate)(struct bgp_proto *p, byte *attr, int len);
-  void (*format)(eattr *ea, byte *buf, int buflen);
+struct bgp_attr_desc {
+  const char *name;
+  uint type;
+  uint flags;
+  void (*export)(struct bgp_export_state *s, eattr *a);
+  int  (*encode)(struct bgp_write_state *s, eattr *a, byte *buf, uint size);
+  void (*decode)(struct bgp_parse_state *s, uint code, uint flags, byte *data, uint len, ea_list **to);
+  void (*format)(eattr *ea, byte *buf, uint size);
 };
 
-#define IGNORE -1
-#define WITHDRAW -2
+static const struct bgp_attr_desc bgp_attr_table[];
+
+static inline int bgp_attr_known(uint code);
+
+eattr *
+bgp_set_attr(ea_list **attrs, struct linpool *pool, uint code, uint flags, uintptr_t val)
+{
+  ASSERT(bgp_attr_known(code));
+
+  ea_list *a = lp_alloc(pool, sizeof(ea_list) + sizeof(eattr));
+  eattr *e = &a->attrs[0];
+
+  a->flags = EALF_SORTED;
+  a->count = 1;
+  a->next = *attrs;
+  *attrs = a;
+
+  e->id = EA_CODE(EAP_BGP, code);
+  e->type = bgp_attr_table[code].type;
+  e->flags = flags;
+
+  if (e->type & EAF_EMBEDDED)
+    e->u.data = (u32) val;
+  else
+    e->u.ptr = (struct adata *) val;
+
+  return e;
+}
+
+
+
+#define REPORT(msg, args...) \
+  ({ log(L_REMOTE "%s: " msg, s->proto->p.name, ## args); })
+
+#define DISCARD(msg, args...) \
+  ({ REPORT(msg, ## args); return; })
+
+#define WITHDRAW(msg, args...) \
+  ({ REPORT(msg, ## args); s->err_withdraw = 1; return; })
+
+#define UNSET(a) \
+  ({ a->type = EAF_TYPE_UNDEF; return; })
+
+#define NEW_BGP		"Discarding %s attribute received from AS4-aware neighbor"
+#define BAD_EBGP	"Discarding %s attribute received from EBGP neighbor"
+#define BAD_LENGTH	"Malformed %s attribute - invalid length (%u)"
+#define BAD_VALUE	"Malformed %s attribute - invalid value (%u)"
+#define NO_MANDATORY	"Missing mandatory %s attribute"
+
+
+static inline int
+bgp_put_attr_hdr3(byte *buf, uint code, uint flags, uint len)
+{
+  *buf++ = flags;
+  *buf++ = code;
+  *buf++ = len;
+  return 3;
+}
+
+static inline int
+bgp_put_attr_hdr4(byte *buf, uint code, uint flags, uint len)
+{
+  *buf++ = flags | BAF_EXT_LEN;
+  *buf++ = code;
+  put_u16(buf, len);
+  return 4;
+}
+
+static inline int
+bgp_put_attr_hdr(byte *buf, uint code, uint flags, uint len)
+{
+  if (len < 256)
+    return bgp_put_attr_hdr3(buf, code, flags, len);
+  else
+    return bgp_put_attr_hdr4(buf, code, flags, len);
+}
 
 static int
-bgp_check_origin(struct bgp_proto *p UNUSED, byte *a, int len UNUSED)
+bgp_encode_u8(struct bgp_write_state *s UNUSED, eattr *a, byte *buf, uint size)
 {
-  if (*a > 2)
-    return 6;
-  return 0;
+  if (size < (3+1))
+    return -1;
+
+  bgp_put_attr_hdr3(buf, EA_ID(a->id), a->flags, 1);
+  buf[3] = a->u.data;
+
+  return 3+1;
 }
 
-static void
-bgp_format_origin(eattr *a, byte *buf, int buflen UNUSED)
+static int
+bgp_encode_u32(struct bgp_write_state *s UNUSED, eattr *a, byte *buf, uint size)
 {
-  static char *bgp_origin_names[] = { "IGP", "EGP", "Incomplete" };
+  if (size < (3+4))
+    return -1;
+
+  bgp_put_attr_hdr3(buf, EA_ID(a->id), a->flags, 4);
+  put_u32(buf+3, a->u.data);
 
-  bsprintf(buf, bgp_origin_names[a->u.data]);
+  return 3+4;
 }
 
 static int
-path_segment_contains(byte *p, int bs, u32 asn)
+bgp_encode_u32s(struct bgp_write_state *s UNUSED, eattr *a, byte *buf, uint size)
 {
-  int i;
-  int len = p[1];
-  p += 2;
+  uint len = a->u.ptr->length;
 
-  for(i=0; i<len; i++)
-    {
-      u32 asn2 = (bs == 4) ? get_u32(p) : get_u16(p);
-      if (asn2 == asn)
-	return 1;
-      p += bs;
-    }
+  if (size < (4+len))
+    return -1;
 
-  return 0;
+  uint hdr = bgp_put_attr_hdr(buf, EA_ID(a->id), a->flags, len);
+  put_u32s(buf + hdr, (u32 *) a->u.ptr->data, len / 4);
+
+  return hdr + len;
 }
 
-/* Validates path attribute, removes AS_CONFED_* segments, and also returns path length */
 static int
-validate_path(struct bgp_proto *p, int as_path, int bs, byte *idata, uint *ilength)
+bgp_put_attr(byte *buf, uint size, uint code, uint flags, byte *data, uint len)
 {
-  int res = 0;
-  u8 *a, *dst;
-  int len, plen;
+  if (size < (4+len))
+    return -1;
 
-  dst = a = idata;
-  len = *ilength;
+  uint hdr = bgp_put_attr_hdr(buf, code, flags, len);
+  memcpy(buf + hdr, data, len);
 
-  while (len)
-    {
-      if (len < 2)
-	return -1;
-
-      plen = 2 + bs * a[1];
-      if (len < plen)
-	return -1;
-
-      if (a[1] == 0)
-        {
-	  log(L_WARN "%s: %s_PATH attribute contains empty segment, skipping it",
-	      p->p.name, as_path ? "AS" : "AS4");
-	  goto skip;
-	}
-
-      switch (a[0])
-	{
-	case AS_PATH_SET:
-	  res++;
-	  break;
-
-	case AS_PATH_SEQUENCE:
-	  res += a[1];
-	  break;
-
-	case AS_PATH_CONFED_SEQUENCE:
-	case AS_PATH_CONFED_SET:
-	  if (as_path && path_segment_contains(a, bs, p->remote_as))
-	    {
-	      log(L_WARN "%s: AS_CONFED_* segment with peer ASN found, misconfigured confederation?", p->p.name);
-	      return -1;
-	    }
-
-	  log(L_WARN "%s: %s_PATH attribute contains AS_CONFED_* segment, skipping segment",
-	      p->p.name, as_path ? "AS" : "AS4");
-	  goto skip;
-
-	default:
-	  return -1;
-	}
-
-      if (dst != a)
-	memmove(dst, a, plen);
-      dst += plen;
-
-    skip:
-      len -= plen;
-      a += plen;
-    }
+  return hdr + len;
+}
 
-  *ilength = dst - idata;
-  return res;
+static int
+bgp_encode_raw(struct bgp_write_state *s UNUSED, eattr *a, byte *buf, uint size)
+{
+  return bgp_put_attr(buf, size, EA_ID(a->id), a->flags, a->u.ptr->data, a->u.ptr->length);
 }
 
-static inline int
-validate_as_path(struct bgp_proto *p, byte *a, int *len)
+
+/*
+ *	Attribute hooks
+ */
+
+static void
+bgp_export_origin(struct bgp_export_state *s, eattr *a)
 {
-  return validate_path(p, 1, p->as4_session ? 4 : 2, a, len);
+  if (a->u.data > 2)
+    WITHDRAW(BAD_VALUE, "ORIGIN", a->u.data);
 }
 
-static inline int
-validate_as4_path(struct bgp_proto *p, struct adata *path)
+static void
+bgp_decode_origin(struct bgp_parse_state *s, uint code UNUSED, uint flags, byte *data, uint len, ea_list **to)
+{
+  if (len != 1)
+    WITHDRAW(BAD_LENGTH, "ORIGIN", len);
+
+  if (data[0] > 2)
+    WITHDRAW(BAD_VALUE, "ORIGIN", data[0]);
+
+  bgp_set_attr_u32(to, s->pool, BA_ORIGIN, flags, data[0]);
+}
+
+static void
+bgp_format_origin(eattr *a, byte *buf, uint size UNUSED)
+{
+  static const char *bgp_origin_names[] = { "IGP", "EGP", "Incomplete" };
+
+  bsprintf(buf, (a->u.data <= 2) ? bgp_origin_names[a->u.data] : "?");
+}
+
+
+static int
+bgp_encode_as_path(struct bgp_write_state *s, eattr *a, byte *buf, uint size)
+{
+  byte *data = a->u.ptr->data;
+  uint len = a->u.ptr->length;
+
+  if (!s->as4_session)
+  {
+    /* Prepare 16-bit AS_PATH (from 32-bit one) in a temporary buffer */
+    byte *src = data;
+    data = alloca(len);
+    len = as_path_32to16(data, src, len);
+  }
+
+  return bgp_put_attr(buf, size, BA_AS_PATH, a->flags, data, len);
+}
+
+static void
+bgp_decode_as_path(struct bgp_parse_state *s, uint code UNUSED, uint flags, byte *data, uint len, ea_list **to)
 {
-  return validate_path(p, 0, 4, path->data, &path->length);
+  char err[128];
+
+  if (!as_path_valid(data, len, (s->as4_session ? 4 : 2), err, sizeof(err)))
+    WITHDRAW("Malformed AS_PATH attribute - %s", err);
+
+  if (!s->as4_session)
+  {
+    /* Prepare 32-bit AS_PATH (from 16-bit one) in a temporary buffer */
+    byte *src = data;
+    data = alloca(2*len);
+    len = as_path_16to32(data, src, len);
+  }
+
+  bgp_set_attr_data(to, s->pool, BA_AS_PATH, flags, data, len);
 }
 
+
 static int
-bgp_check_next_hop(struct bgp_proto *p UNUSED, byte *a UNUSED6, int len UNUSED6)
+bgp_encode_next_hop(struct bgp_write_state *s, eattr *a, byte *buf, uint size)
 {
-#ifdef IPV6
-  return IGNORE;
-#else
-  ip_addr addr;
+  /*
+   * The NEXT_HOP attribute is used only in traditional (IPv4) BGP. In MP-BGP,
+   * the next hop is encoded as a part of the MP_REACH_NLRI attribute, so we
+   * store it and encode it later by AFI-specific hooks.
+   */
+
+  if (s->channel->afi == BGP_AF_IPV4)
+  {
+    ASSERT(a->u.ptr->length == sizeof(ip_addr));
+
+    if (size < (3+4))
+      return -1;
 
-  memcpy(&addr, a, len);
-  ipa_ntoh(addr);
-  if (ipa_classify(addr) & IADDR_HOST)
+    bgp_put_attr_hdr3(buf, BA_NEXT_HOP, a->flags, 4);
+    put_ip4(buf+3, ipa_to_ip4( *(ip_addr *) a->u.ptr->data ));
+
+    return 3+4;
+  }
+  else
+  {
+    s->mp_next_hop = a;
     return 0;
+  }
+}
+
+static void
+bgp_decode_next_hop(struct bgp_parse_state *s, uint code UNUSED, uint flags UNUSED, byte *data, uint len, ea_list **to UNUSED)
+{
+  if (len != 4)
+    WITHDRAW(BAD_LENGTH, "NEXT_HOP", len);
+
+  /* Semantic checks are done later */
+  s->ip_next_hop_len = len;
+  s->ip_next_hop_data = data;
+}
+
+/* TODO: This function should use AF-specific hook */
+static void
+bgp_format_next_hop(eattr *a, byte *buf, uint size UNUSED)
+{
+  ip_addr *nh = (void *) a->u.ptr->data;
+  uint len = a->u.ptr->length;
+
+  ASSERT((len == 16) || (len == 32));
+
+  /* in IPv6, we may have two addresses in NEXT HOP */
+  if ((len == 16) || ipa_zero(nh[1]))
+    bsprintf(buf, "%I", nh[0]);
   else
-    return 8;
-#endif
+    bsprintf(buf, "%I %I", nh[0], nh[1]);
 }
 
+
 static void
-bgp_format_next_hop(eattr *a, byte *buf, int buflen UNUSED)
+bgp_decode_med(struct bgp_parse_state *s, uint code UNUSED, uint flags, byte *data, uint len, ea_list **to)
 {
-  ip_addr *ipp = (ip_addr *) a->u.ptr->data;
-#ifdef IPV6
-  /* in IPv6, we might have two addresses in NEXT HOP */
-  if ((a->u.ptr->length == NEXT_HOP_LENGTH) && ipa_nonzero(ipp[1]))
-    {
-      bsprintf(buf, "%I %I", ipp[0], ipp[1]);
-      return;
-    }
-#endif
+  if (len != 4)
+    WITHDRAW(BAD_LENGTH, "MULTI_EXIT_DISC", len);
 
-  bsprintf(buf, "%I", ipp[0]);
+  u32 val = get_u32(data);
+  bgp_set_attr_u32(to, s->pool, BA_MULTI_EXIT_DISC, flags, val);
 }
 
-static int
-bgp_check_aggregator(struct bgp_proto *p, byte *a UNUSED, int len)
+
+static void
+bgp_export_local_pref(struct bgp_export_state *s, eattr *a)
 {
-  int exp_len = p->as4_session ? 8 : 6;
-  
-  return (len == exp_len) ? 0 : WITHDRAW;
+  if (!s->proto->is_interior)
+    UNSET(a);
 }
 
 static void
-bgp_format_aggregator(eattr *a, byte *buf, int buflen UNUSED)
+bgp_decode_local_pref(struct bgp_parse_state *s, uint code UNUSED, uint flags, byte *data, uint len, ea_list **to)
 {
-  struct adata *ad =  a->u.ptr;
-  byte *data = ad->data;
-  u32 as;
+  if (!s->proto->is_interior)
+    DISCARD(BAD_EBGP, "LOCAL_PREF");
 
-  as = get_u32(data);
-  data += 4;
+  if (len != 4)
+    WITHDRAW(BAD_LENGTH, "LOCAL_PREF", len);
 
-  bsprintf(buf, "%d.%d.%d.%d AS%u", data[0], data[1], data[2], data[3], as);
+  u32 val = get_u32(data);
+  bgp_set_attr_u32(to, s->pool, BA_LOCAL_PREF, flags, val);
 }
 
-static int
-bgp_check_community(struct bgp_proto *p UNUSED, byte *a UNUSED, int len)
+
+static void
+bgp_decode_atomic_aggr(struct bgp_parse_state *s, uint code UNUSED, uint flags, byte *data UNUSED, uint len, ea_list **to)
 {
-  return ((len % 4) == 0) ? 0 : WITHDRAW;
+  if (len != 0)
+    DISCARD(BAD_LENGTH, "ATOMIC_AGGR", len);
+
+  bgp_set_attr_data(to, s->pool, BA_ATOMIC_AGGR, flags, NULL, 0);
 }
 
 static int
-bgp_check_cluster_list(struct bgp_proto *p UNUSED, byte *a UNUSED, int len)
+bgp_encode_aggregator(struct bgp_write_state *s, eattr *a, byte *buf, uint size)
 {
-  return ((len % 4) == 0) ? 0 : 5;
+  byte *data = a->u.ptr->data;
+  uint len = a->u.ptr->length;
+
+  if (!s->as4_session)
+  {
+    /* Prepare 16-bit AGGREGATOR (from 32-bit one) in a temporary buffer */
+    byte *src = data;
+    data = alloca(6);
+    len = aggregator_32to16(data, src);
+  }
+
+  return bgp_put_attr(buf, size, BA_AGGREGATOR, a->flags, data, len);
 }
 
 static void
-bgp_format_cluster_list(eattr *a, byte *buf, int buflen)
+bgp_decode_aggregator(struct bgp_parse_state *s, uint code UNUSED, uint flags, byte *data, uint len, ea_list **to)
 {
-  /* Truncates cluster lists larger than buflen, probably not a problem */
-  int_set_format(a->u.ptr, 0, -1, buf, buflen);
+  if (len != (s->as4_session ? 8 : 6))
+    DISCARD(BAD_LENGTH, "AGGREGATOR", len);
+
+  if (!s->as4_session)
+  {
+    /* Prepare 32-bit AGGREGATOR (from 16-bit one) in a temporary buffer */
+    byte *src = data;
+    data = alloca(8);
+    len = aggregator_16to32(data, src);
+  }
+
+  bgp_set_attr_data(to, s->pool, BA_AGGREGATOR, flags, data, len);
 }
 
-static int
-bgp_check_reach_nlri(struct bgp_proto *p UNUSED, byte *a UNUSED, int len UNUSED)
+static void
+bgp_format_aggregator(eattr *a, byte *buf, uint size UNUSED)
 {
-#ifdef IPV6
-  p->mp_reach_start = a;
-  p->mp_reach_len = len;
-#endif
-  return IGNORE;
+  byte *data = a->u.ptr->data;
+
+  bsprintf(buf, "%I4 AS%u", get_ip4(data+4), get_u32(data+0));
 }
 
-static int
-bgp_check_unreach_nlri(struct bgp_proto *p UNUSED, byte *a UNUSED, int len UNUSED)
+
+static void
+bgp_export_community(struct bgp_export_state *s, eattr *a)
 {
-#ifdef IPV6
-  p->mp_unreach_start = a;
-  p->mp_unreach_len = len;
-#endif
-  return IGNORE;
+  if (a->u.ptr->length == 0)
+    UNSET(a);
+
+  a->u.ptr = int_set_sort(s->pool, a->u.ptr);
 }
 
-static int
-bgp_check_ext_community(struct bgp_proto *p UNUSED, byte *a UNUSED, int len)
+static void
+bgp_decode_community(struct bgp_parse_state *s, uint code UNUSED, uint flags, byte *data, uint len, ea_list **to)
 {
-  return ((len % 8) == 0) ? 0 : WITHDRAW;
+  if (!len || (len % 4))
+    WITHDRAW(BAD_LENGTH, "COMMUNITY", len);
+
+  struct adata *ad = lp_alloc_adata(s->pool, len);
+  get_u32s(data, (u32 *) ad->data, len / 4);
+  bgp_set_attr_ptr(to, s->pool, BA_COMMUNITY, flags, ad);
 }
 
-static int
-bgp_check_large_community(struct bgp_proto *p UNUSED, byte *a UNUSED, int len)
-{
-  return ((len % 12) == 0) ? 0 : WITHDRAW;
-}
-
-
-static struct attr_desc bgp_attr_table[] = {
-  { NULL, -1, 0, 0, 0,								/* Undefined */
-    NULL, NULL },
-  { "origin", 1, BAF_TRANSITIVE, EAF_TYPE_INT, 1,				/* BA_ORIGIN */
-    bgp_check_origin, bgp_format_origin },
-  { "as_path", -1, BAF_TRANSITIVE, EAF_TYPE_AS_PATH, 1,				/* BA_AS_PATH */
-    NULL, NULL }, /* is checked by validate_as_path() as a special case */
-  { "next_hop", 4, BAF_TRANSITIVE, EAF_TYPE_IP_ADDRESS, 1,			/* BA_NEXT_HOP */
-    bgp_check_next_hop, bgp_format_next_hop },
-  { "med", 4, BAF_OPTIONAL, EAF_TYPE_INT, 1,					/* BA_MULTI_EXIT_DISC */
-    NULL, NULL },
-  { "local_pref", 4, BAF_TRANSITIVE, EAF_TYPE_INT, 0,				/* BA_LOCAL_PREF */
-    NULL, NULL },
-  { "atomic_aggr", 0, BAF_TRANSITIVE, EAF_TYPE_OPAQUE, 1,			/* BA_ATOMIC_AGGR */
-    NULL, NULL },
-  { "aggregator", -1, BAF_OPTIONAL | BAF_TRANSITIVE, EAF_TYPE_OPAQUE, 1,	/* BA_AGGREGATOR */
-    bgp_check_aggregator, bgp_format_aggregator },
-  { "community", -1, BAF_OPTIONAL | BAF_TRANSITIVE, EAF_TYPE_INT_SET, 1,	/* BA_COMMUNITY */
-    bgp_check_community, NULL },
-  { "originator_id", 4, BAF_OPTIONAL, EAF_TYPE_ROUTER_ID, 0,			/* BA_ORIGINATOR_ID */
-    NULL, NULL },
-  { "cluster_list", -1, BAF_OPTIONAL, EAF_TYPE_INT_SET, 0,			/* BA_CLUSTER_LIST */
-    bgp_check_cluster_list, bgp_format_cluster_list }, 
-  { .name = NULL },								/* BA_DPA */
-  { .name = NULL },								/* BA_ADVERTISER */
-  { .name = NULL },								/* BA_RCID_PATH */
-  { "mp_reach_nlri", -1, BAF_OPTIONAL, EAF_TYPE_OPAQUE, 1,			/* BA_MP_REACH_NLRI */
-    bgp_check_reach_nlri, NULL },
-  { "mp_unreach_nlri", -1, BAF_OPTIONAL, EAF_TYPE_OPAQUE, 1,			/* BA_MP_UNREACH_NLRI */
-    bgp_check_unreach_nlri, NULL },
-  { "ext_community", -1, BAF_OPTIONAL | BAF_TRANSITIVE, EAF_TYPE_EC_SET, 1,	/* BA_EXT_COMMUNITY */
-    bgp_check_ext_community, NULL },
-  { "as4_path", -1, BAF_OPTIONAL | BAF_TRANSITIVE, EAF_TYPE_OPAQUE, 1,		/* BA_AS4_PATH */
-    NULL, NULL },
-  { "as4_aggregator", -1, BAF_OPTIONAL | BAF_TRANSITIVE, EAF_TYPE_OPAQUE, 1,	/* BA_AS4_PATH */
-    NULL, NULL },
-  [BA_LARGE_COMMUNITY] =
-  { "large_community", -1, BAF_OPTIONAL | BAF_TRANSITIVE, EAF_TYPE_LC_SET, 1,
-    bgp_check_large_community, NULL }
-};
 
-/* BA_AS4_PATH is type EAF_TYPE_OPAQUE and not type EAF_TYPE_AS_PATH.
- * It does not matter as this attribute does not appear on routes in the routing table.
- */
+static void
+bgp_export_originator_id(struct bgp_export_state *s, eattr *a)
+{
+  if (!s->proto->is_internal)
+    UNSET(a);
+}
 
-#define ATTR_KNOWN(code) ((code) < ARRAY_SIZE(bgp_attr_table) && bgp_attr_table[code].name)
+static void
+bgp_decode_originator_id(struct bgp_parse_state *s, uint code UNUSED, uint flags, byte *data, uint len, ea_list **to)
+{
+  if (!s->proto->is_internal)
+    DISCARD(BAD_EBGP, "ORIGINATOR_ID");
+
+  if (len != 4)
+    WITHDRAW(BAD_LENGTH, "ORIGINATOR_ID", len);
+
+  u32 val = get_u32(data);
+  bgp_set_attr_u32(to, s->pool, BA_ORIGINATOR_ID, flags, val);
+}
 
-static inline struct adata *
-bgp_alloc_adata(struct linpool *pool, unsigned len)
+
+static void
+bgp_export_cluster_list(struct bgp_export_state *s UNUSED, eattr *a)
 {
-  struct adata *ad = lp_alloc(pool, sizeof(struct adata) + len);
-  ad->length = len;
-  return ad;
+  if (!s->proto->is_internal)
+    UNSET(a);
+
+  if (a->u.ptr->length == 0)
+    UNSET(a);
 }
 
 static void
-bgp_set_attr(eattr *e, unsigned attr, uintptr_t val)
+bgp_decode_cluster_list(struct bgp_parse_state *s, uint code UNUSED, uint flags, byte *data, uint len, ea_list **to)
 {
-  ASSERT(ATTR_KNOWN(attr));
-  e->id = EA_CODE(EAP_BGP, attr);
-  e->type = bgp_attr_table[attr].type;
-  e->flags = bgp_attr_table[attr].expected_flags;
-  if (e->type & EAF_EMBEDDED)
-    e->u.data = val;
-  else
-    e->u.ptr = (struct adata *) val;
+  if (!s->proto->is_internal)
+    DISCARD(BAD_EBGP, "CLUSTER_LIST");
+
+  if (!len || (len % 4))
+    WITHDRAW(BAD_LENGTH, "CLUSTER_LIST", len);
+
+  struct adata *ad = lp_alloc_adata(s->pool, len);
+  get_u32s(data, (u32 *) ad->data, len / 4);
+  bgp_set_attr_ptr(to, s->pool, BA_CLUSTER_LIST, flags, ad);
 }
 
-static byte *
-bgp_set_attr_wa(eattr *e, struct linpool *pool, unsigned attr, unsigned len)
+static void
+bgp_format_cluster_list(eattr *a, byte *buf, uint size)
 {
-  struct adata *ad = bgp_alloc_adata(pool, len);
-  bgp_set_attr(e, attr, (uintptr_t) ad);
-  return ad->data;
+  /* Truncates cluster lists larger than buflen, probably not a problem */
+  int_set_format(a->u.ptr, 0, -1, buf, size);
 }
 
-void
-bgp_attach_attr(ea_list **to, struct linpool *pool, unsigned attr, uintptr_t val)
+
+static inline u32
+get_af3(byte *buf)
 {
-  ea_list *a = lp_alloc(pool, sizeof(ea_list) + sizeof(eattr));
-  a->next = *to;
-  *to = a;
-  a->flags = EALF_SORTED;
-  a->count = 1;
-  bgp_set_attr(a->attrs, attr, val);
+  return (get_u16(buf) << 16) | buf[2];
+}
+
+static void
+bgp_decode_mp_reach_nlri(struct bgp_parse_state *s, uint code UNUSED, uint flags UNUSED, byte *data, uint len, ea_list **to UNUSED)
+{
+  /*
+   *	2 B	MP_REACH_NLRI data - Address Family Identifier
+   *	1 B	MP_REACH_NLRI data - Subsequent Address Family Identifier
+   *	1 B	MP_REACH_NLRI data - Length of Next Hop Network Address
+   *	var	MP_REACH_NLRI data - Network Address of Next Hop
+   *	1 B	MP_REACH_NLRI data - Reserved (zero)
+   *	var	MP_REACH_NLRI data - Network Layer Reachability Information
+   */
+
+  if ((len < 5) || (len < (5 + (uint) data[3])))
+    bgp_parse_error(s, 9);
+
+  s->mp_reach_af = get_af3(data);
+  s->mp_next_hop_len = data[3];
+  s->mp_next_hop_data = data + 4;
+  s->mp_reach_len = len - 5 - s->mp_next_hop_len;
+  s->mp_reach_nlri = data + 5 + s->mp_next_hop_len;
 }
 
-byte *
-bgp_attach_attr_wa(ea_list **to, struct linpool *pool, unsigned attr, unsigned len)
+
+static void
+bgp_decode_mp_unreach_nlri(struct bgp_parse_state *s, uint code UNUSED, uint flags UNUSED, byte *data, uint len, ea_list **to UNUSED)
 {
-  struct adata *ad = bgp_alloc_adata(pool, len);
-  bgp_attach_attr(to, pool, attr, (uintptr_t) ad);
-  return ad->data;
+  /*
+   *	2 B	MP_UNREACH_NLRI data - Address Family Identifier
+   *	1 B	MP_UNREACH_NLRI data - Subsequent Address Family Identifier
+   *	var	MP_UNREACH_NLRI data - Network Layer Reachability Information
+   */
+
+  if (len < 3)
+    bgp_parse_error(s, 9);
+
+  s->mp_unreach_af = get_af3(data);
+  s->mp_unreach_len = len - 3;
+  s->mp_unreach_nlri = data + 3;
 }
 
-static int
-bgp_encode_attr_hdr(byte *dst, uint flags, unsigned code, int len)
+
+static void
+bgp_export_ext_community(struct bgp_export_state *s, eattr *a)
 {
-  int wlen;
+  if (a->u.ptr->length == 0)
+    UNSET(a);
 
-  DBG("\tAttribute %02x (%d bytes, flags %02x)\n", code, len, flags);
+  a->u.ptr = ec_set_sort(s->pool, a->u.ptr);
+}
 
-  if (len < 256)
-    {
-      *dst++ = flags;
-      *dst++ = code;
-      *dst++ = len;
-      wlen = 3;
-    }
-  else
-    {
-      *dst++ = flags | BAF_EXT_LEN;
-      *dst++ = code;
-      put_u16(dst, len);
-      wlen = 4;
-    }
+static void
+bgp_decode_ext_community(struct bgp_parse_state *s, uint code UNUSED, uint flags, byte *data, uint len, ea_list **to)
+{
+  if (!len || (len % 8))
+    WITHDRAW(BAD_LENGTH, "EXT_COMMUNITY", len);
 
-  return wlen;
+  struct adata *ad = lp_alloc_adata(s->pool, len);
+  get_u32s(data, (u32 *) ad->data, len / 4);
+  bgp_set_attr_ptr(to, s->pool, BA_EXT_COMMUNITY, flags, ad);
 }
 
+
 static void
-aggregator_convert_to_old(struct adata *aggr, byte *dst, int *new_used)
+bgp_decode_as4_aggregator(struct bgp_parse_state *s, uint code UNUSED, uint flags, byte *data, uint len, ea_list **to)
 {
-  byte *src = aggr->data;
-  *new_used = 0;
+  if (s->as4_session)
+    DISCARD(NEW_BGP, "AS4_AGGREGATOR");
 
-  u32 as = get_u32(src);
-  if (as > 0xFFFF) 
-    {
-      as = AS_TRANS;
-      *new_used = 1;
-    }
-  put_u16(dst, as);
+  if (len != 8)
+    DISCARD(BAD_LENGTH, "AS4_AGGREGATOR", len);
 
-  /* Copy IPv4 address */
-  memcpy(dst + 2, src + 4, 4);
+  bgp_set_attr_data(to, s->pool, BA_AS4_AGGREGATOR, flags, data, len);
 }
 
 static void
-aggregator_convert_to_new(struct adata *aggr, byte *dst)
+bgp_decode_as4_path(struct bgp_parse_state *s, uint code UNUSED, uint flags, byte *data, uint len, ea_list **to)
 {
-  byte *src = aggr->data;
+  char err[128];
+
+  if (s->as4_session)
+    DISCARD(NEW_BGP, "AS4_PATH");
+
+  if (len < 6)
+    DISCARD(BAD_LENGTH, "AS4_PATH", len);
 
-  u32 as   = get_u16(src);
-  put_u32(dst, as);
+  if (!as_path_valid(data, len, 4, err, sizeof(err)))
+    DISCARD("Malformed AS4_PATH attribute - %s", err);
 
-  /* Copy IPv4 address */
-  memcpy(dst + 4, src + 2, 4);
+  /* XXXX remove CONFED segments */
+  bgp_set_attr_data(to, s->pool, BA_AS4_PATH, flags, data, len);
 }
 
-static int
-bgp_get_attr_len(eattr *a)
+static void
+bgp_export_large_community(struct bgp_export_state *s, eattr *a)
 {
-  int len;
-  if (ATTR_KNOWN(EA_ID(a->id)))
-    {
-      int code = EA_ID(a->id);
-      struct attr_desc *desc = &bgp_attr_table[code];
-      len = desc->expected_length;
-      if (len < 0)
-	{
-	  ASSERT(!(a->type & EAF_EMBEDDED));
-	  len = a->u.ptr->length;
-	}
-    }
+  if (a->u.ptr->length == 0)
+    UNSET(a);
+
+  a->u.ptr = lc_set_sort(s->pool, a->u.ptr);
+}
+
+static void
+bgp_decode_large_community(struct bgp_parse_state *s, uint code UNUSED, uint flags, byte *data, uint len, ea_list **to)
+{
+  if (!len || (len % 12))
+    WITHDRAW(BAD_LENGTH, "LARGE_COMMUNITY", len);
+
+  struct adata *ad = lp_alloc_adata(s->pool, len);
+  get_u32s(data, (u32 *) ad->data, len / 4);
+  bgp_set_attr_ptr(to, s->pool, BA_LARGE_COMMUNITY, flags, ad);
+}
+
+static inline void
+bgp_decode_unknown(struct bgp_parse_state *s, uint code, uint flags, byte *data, uint len, ea_list **to)
+{
+  bgp_set_attr_data(to, s->pool, code, flags, data, len);
+}
+
+
+/*
+ *	Attribute table
+ */
+
+static const struct bgp_attr_desc bgp_attr_table[] = {
+  [BA_ORIGIN] = {
+    .name = "origin",
+    .type = EAF_TYPE_INT,
+    .flags = BAF_TRANSITIVE,
+    .export = bgp_export_origin,
+    .encode = bgp_encode_u8,
+    .decode = bgp_decode_origin,
+    .format = bgp_format_origin,
+  },
+  [BA_AS_PATH] = {
+    .name = "as_path",
+    .type = EAF_TYPE_AS_PATH,
+    .flags = BAF_TRANSITIVE,
+    .encode = bgp_encode_as_path,
+    .decode = bgp_decode_as_path,
+  },
+  [BA_NEXT_HOP] = {
+    .name = "next_hop",
+    .type = EAF_TYPE_IP_ADDRESS,
+    .flags = BAF_TRANSITIVE,
+    .encode = bgp_encode_next_hop,
+    .decode = bgp_decode_next_hop,
+    .format = bgp_format_next_hop,
+  },
+  [BA_MULTI_EXIT_DISC] = {
+    .name = "med",
+    .type = EAF_TYPE_INT,
+    .flags = BAF_OPTIONAL,
+    .encode = bgp_encode_u32,
+    .decode = bgp_decode_med,
+  },
+  [BA_LOCAL_PREF] = {
+    .name = "local_pref",
+    .type = EAF_TYPE_INT,
+    .flags = BAF_TRANSITIVE,
+    .export = bgp_export_local_pref,
+    .encode = bgp_encode_u32,
+    .decode = bgp_decode_local_pref,
+  },
+  [BA_ATOMIC_AGGR] = {
+    .name = "atomic_aggr",
+    .type = EAF_TYPE_OPAQUE,
+    .flags = BAF_TRANSITIVE,
+    .encode = bgp_encode_raw,
+    .decode = bgp_decode_atomic_aggr,
+  },
+  [BA_AGGREGATOR] = {
+    .name = "aggregator",
+    .type = EAF_TYPE_OPAQUE,
+    .flags = BAF_OPTIONAL | BAF_TRANSITIVE,
+    .encode = bgp_encode_aggregator,
+    .decode = bgp_decode_aggregator,
+    .format = bgp_format_aggregator,
+  },
+  [BA_COMMUNITY] = {
+    .name = "community",
+    .type = EAF_TYPE_INT_SET,
+    .flags = BAF_OPTIONAL | BAF_TRANSITIVE,
+    .export = bgp_export_community,
+    .encode = bgp_encode_u32s,
+    .decode = bgp_decode_community,
+  },
+  [BA_ORIGINATOR_ID] = {
+    .name = "originator_id",
+    .type = EAF_TYPE_ROUTER_ID,
+    .flags = BAF_OPTIONAL,
+    .export = bgp_export_originator_id,
+    .encode = bgp_encode_u32,
+    .decode = bgp_decode_originator_id,
+  },
+  [BA_CLUSTER_LIST] = {
+    .name = "cluster_list",
+    .type = EAF_TYPE_INT_SET,
+    .flags = BAF_OPTIONAL,
+    .export = bgp_export_cluster_list,
+    .encode = bgp_encode_u32s,
+    .decode = bgp_decode_cluster_list,
+    .format = bgp_format_cluster_list,
+  },
+  [BA_MP_REACH_NLRI] = {
+    .name = "mp_reach_nlri",
+    .type = EAF_TYPE_OPAQUE,
+    .flags = BAF_OPTIONAL,
+    .decode = bgp_decode_mp_reach_nlri,
+  },
+  [BA_MP_UNREACH_NLRI] = {
+    .name = "mp_unreach_nlri",
+    .type = EAF_TYPE_OPAQUE,
+    .flags = BAF_OPTIONAL,
+    .decode = bgp_decode_mp_unreach_nlri,
+  },
+  [BA_EXT_COMMUNITY] = {
+    .name = "ext_community",
+    .type = EAF_TYPE_EC_SET,
+    .flags = BAF_OPTIONAL | BAF_TRANSITIVE,
+    .export = bgp_export_ext_community,
+    .encode = bgp_encode_u32s,
+    .decode = bgp_decode_ext_community,
+  },
+  [BA_AS4_PATH] = {
+    .name = "as4_path",
+    .type = EAF_TYPE_AS_PATH,
+    .flags = BAF_OPTIONAL | BAF_TRANSITIVE,
+    .encode = bgp_encode_raw,
+    .decode = bgp_decode_as4_path,
+  },
+  [BA_AS4_AGGREGATOR] = {
+    .name = "as4_aggregator",
+    .type = EAF_TYPE_OPAQUE,
+    .flags = BAF_OPTIONAL | BAF_TRANSITIVE,
+    .encode = bgp_encode_raw,
+    .decode = bgp_decode_as4_aggregator,
+    .format = bgp_format_aggregator,
+  },
+  [BA_LARGE_COMMUNITY] = {
+    .name = "large_community",
+    .type = EAF_TYPE_LC_SET,
+    .flags = BAF_OPTIONAL | BAF_TRANSITIVE,
+    .export = bgp_export_large_community,
+    .encode = bgp_encode_u32s,
+    .decode = bgp_decode_large_community,
+  },
+};
+
+static inline int
+bgp_attr_known(uint code)
+{
+  return (code < ARRAY_SIZE(bgp_attr_table)) && bgp_attr_table[code].name;
+}
+
+
+/*
+ *	Attribute export
+ */
+
+static inline void
+bgp_export_attr(struct bgp_export_state *s, eattr *a, ea_list *to)
+{
+  if (EA_PROTO(a->id) != EAP_BGP)
+    return;
+
+  uint code = EA_ID(a->id);
+
+  if (bgp_attr_known(code))
+  {
+    const struct bgp_attr_desc *desc = &bgp_attr_table[code];
+
+    /* The flags might have been zero if the attr was added by filters */
+    a->flags = (a->flags & BAF_PARTIAL) | desc->flags;
+
+    /* Set partial bit if new opt-trans attribute is attached to non-local route */
+    if ((s->src != NULL) && (a->type & EAF_ORIGINATED) &&
+	(a->flags & BAF_OPTIONAL) && (a->flags & BAF_TRANSITIVE))
+      a->flags |= BAF_PARTIAL;
+
+    /* Call specific hook */
+    CALL(desc->export, s, a);
+
+    /* Attribute might become undefined in hook */
+    if ((a->type & EAF_TYPE_MASK) == EAF_TYPE_UNDEF)
+      return;
+  }
   else
-    {
-      ASSERT((a->type & EAF_TYPE_MASK) == EAF_TYPE_OPAQUE);
-      len = a->u.ptr->length;
-    }
-  
-  return len;
+  {
+    /* Don't re-export unknown non-transitive attributes */
+    if (!(a->flags & BAF_TRANSITIVE))
+      return;
+
+    a->flags |= BAF_PARTIAL;
+  }
+
+  /* Append updated attribute */
+  to->attrs[to->count++] = *a;
 }
 
-#define ADVANCE(w, r, l) do { r -= l; w += l; } while (0)
+/**
+ * bgp_export_attrs - export BGP attributes
+ * @s: BGP export state
+ * @attrs: a list of extended attributes
+ *
+ * The bgp_export_attrs() function takes a list of attributes and merges it to
+ * one newly allocated and sorted segment. Attributes are validated and
+ * normalized by type-specific export hooks and attribute flags are updated.
+ * Some attributes may be eliminated (e.g. unknown non-tranitive attributes, or
+ * empty community sets).
+ *
+ * Result: one sorted attribute list segment, or NULL if attributes are unsuitable.
+ */
+static inline ea_list *
+bgp_export_attrs(struct bgp_export_state *s, ea_list *attrs)
+{
+  /* Merge the attribute list */
+  ea_list *new = lp_alloc(s->pool, ea_scan(attrs));
+  ea_merge(attrs, new);
+  ea_sort(new);
+
+  uint i, count;
+  count = new->count;
+  new->count = 0;
+
+  /* Export each attribute */
+  for (i = 0; i < count; i++)
+    bgp_export_attr(s, &new->attrs[i], new);
+
+  if (s->err_withdraw)
+    return NULL;
+
+  return new;
+
+}
+
+
+/*
+ *	Attribute encoding
+ */
+
+static inline int
+bgp_encode_attr(struct bgp_write_state *s, eattr *a, byte *buf, uint size)
+{
+  ASSERT(EA_PROTO(a->id) == EAP_BGP);
+
+  uint code = EA_ID(a->id);
+
+  if (bgp_attr_known(code))
+    return bgp_attr_table[code].encode(s, a, buf, size);
+  else
+    return bgp_encode_raw(s, a, buf, size);
+}
 
 /**
  * bgp_encode_attrs - encode BGP attributes
- * @p: BGP instance
- * @w: buffer
+ * @s: BGP write state
  * @attrs: a list of extended attributes
- * @remains: remaining space in the buffer
+ * @buf: buffer
+ * @end: buffer end
  *
  * The bgp_encode_attrs() function takes a list of extended attributes
  * and converts it to its BGP representation (a part of an Update message).
  *
  * Result: Length of the attribute block generated or -1 if not enough space.
  */
-uint
-bgp_encode_attrs(struct bgp_proto *p, byte *w, ea_list *attrs, int remains)
+int
+bgp_encode_attrs(struct bgp_write_state *s, ea_list *attrs, byte *buf, byte *end)
 {
-  uint i, code, type, flags;
-  byte *start = w;
-  int len, rv;
+  byte *pos = buf;
+  int i, len;
 
-  for(i=0; i<attrs->count; i++)
-    {
-      eattr *a = &attrs->attrs[i];
-      ASSERT(EA_PROTO(a->id) == EAP_BGP);
-      code = EA_ID(a->id);
-
-#ifdef IPV6
-      /* When talking multiprotocol BGP, the NEXT_HOP attributes are used only temporarily. */
-      if (code == BA_NEXT_HOP)
-	continue;
-#endif
-
-      /* When AS4-aware BGP speaker is talking to non-AS4-aware BGP speaker,
-       * we have to convert our 4B AS_PATH to 2B AS_PATH and send our AS_PATH 
-       * as optional AS4_PATH attribute.
-       */
-      if ((code == BA_AS_PATH) && (! p->as4_session))
-	{
-	  len = a->u.ptr->length;
-
-	  if (remains < (len + 4))
-	    goto err_no_buffer;
-
-	  /* Using temporary buffer because don't know a length of created attr
-	   * and therefore a length of a header. Perhaps i should better always
-	   * use BAF_EXT_LEN. */
-	  
-	  byte buf[len];
-	  int new_used;
-	  int nl = as_path_convert_to_old(a->u.ptr, buf, &new_used);
-
-	  DBG("BGP: Encoding old AS_PATH\n");
-	  rv = bgp_encode_attr_hdr(w, BAF_TRANSITIVE, BA_AS_PATH, nl);
-	  ADVANCE(w, remains, rv);
-	  memcpy(w, buf, nl);
-	  ADVANCE(w, remains, nl);
-
-	  if (! new_used)
-	    continue;
-
-	  if (remains < (len + 4))
-	    goto err_no_buffer;
-
-	  /* We should discard AS_CONFED_SEQUENCE or AS_CONFED_SET path segments 
-	   * here but we don't support confederations and such paths we already
-	   * discarded in bgp_check_as_path().
-	   */
-
-	  DBG("BGP: Encoding AS4_PATH\n");
-	  rv = bgp_encode_attr_hdr(w, BAF_OPTIONAL | BAF_TRANSITIVE, BA_AS4_PATH, len);
-	  ADVANCE(w, remains, rv);
-	  memcpy(w, a->u.ptr->data, len);
-	  ADVANCE(w, remains, len);
-
-	  continue;
-	}
-
-      /* The same issue with AGGREGATOR attribute */
-      if ((code == BA_AGGREGATOR) && (! p->as4_session))
-	{
-	  int new_used;
-
-	  len = 6;
-	  if (remains < (len + 3))
-	    goto err_no_buffer;
-
-	  rv = bgp_encode_attr_hdr(w, BAF_OPTIONAL | BAF_TRANSITIVE, BA_AGGREGATOR, len);
-	  ADVANCE(w, remains, rv);
-	  aggregator_convert_to_old(a->u.ptr, w, &new_used);
-	  ADVANCE(w, remains, len);
-
-	  if (! new_used)
-	    continue;
-
-	  len = 8;
-	  if (remains < (len + 3))
-	    goto err_no_buffer;
-
-	  rv = bgp_encode_attr_hdr(w, BAF_OPTIONAL | BAF_TRANSITIVE, BA_AS4_AGGREGATOR, len);
-	  ADVANCE(w, remains, rv);
-	  memcpy(w, a->u.ptr->data, len);
-	  ADVANCE(w, remains, len);
-
-	  continue;
-	}
-
-      /* Standard path continues here ... */
-
-      type = a->type & EAF_TYPE_MASK;
-      flags = a->flags & (BAF_OPTIONAL | BAF_TRANSITIVE | BAF_PARTIAL);
-      len = bgp_get_attr_len(a);
-
-      /* Skip empty sets */ 
-      if (((type == EAF_TYPE_INT_SET) || (type == EAF_TYPE_EC_SET) || (type == EAF_TYPE_LC_SET)) && (len == 0))
-	continue; 
-
-      if (remains < len + 4)
-	goto err_no_buffer;
-
-      rv = bgp_encode_attr_hdr(w, flags, code, len);
-      ADVANCE(w, remains, rv);
-
-      switch (type)
-	{
-	case EAF_TYPE_INT:
-	case EAF_TYPE_ROUTER_ID:
-	  if (len == 4)
-	    put_u32(w, a->u.data);
-	  else
-	    *w = a->u.data;
-	  break;
-	case EAF_TYPE_IP_ADDRESS:
-	  {
-	    ip_addr ip = *(ip_addr *)a->u.ptr->data;
-	    ipa_hton(ip);
-	    memcpy(w, &ip, len);
-	    break;
-	  }
-	case EAF_TYPE_INT_SET:
-	case EAF_TYPE_LC_SET:
-	case EAF_TYPE_EC_SET:
-	  {
-	    u32 *z = int_set_get_data(a->u.ptr);
-	    int i;
-	    for(i=0; i<len; i+=4)
-	      put_u32(w+i, *z++);
-	    break;
-	  }
-	case EAF_TYPE_OPAQUE:
-	case EAF_TYPE_AS_PATH:
-	  memcpy(w, a->u.ptr->data, len);
-	  break;
-	default:
-	  bug("bgp_encode_attrs: unknown attribute type %02x", a->type);
-	}
-      ADVANCE(w, remains, len);
-    }
-  return w - start;
+  for (i = 0; i < attrs->count; i++)
+  {
+    len = bgp_encode_attr(s, &attrs->attrs[i], pos, end - pos);
 
- err_no_buffer:
-  return -1;
+    if (len < 0)
+      return -1;
+
+    pos += len;
+  }
+
+  return pos - buf;
 }
 
+
 /*
-static void
-bgp_init_prefix(struct fib_node *N)
+ *	Attribute decoding
+ */
+
+static void bgp_process_as4_attrs(ea_list **attrs, struct linpool *pool);
+
+static inline int
+bgp_as_path_loopy(struct bgp_proto *p, ea_list *attrs, u32 asn)
 {
-  struct bgp_prefix *p = (struct bgp_prefix *) N;
-  p->bucket_node.next = NULL;
+  eattr *e = bgp_find_attr(attrs, BA_AS_PATH);
+  int num = p->cf->allow_local_as + 1;
+  return (e && (num > 0) && as_path_contains(e->u.ptr, asn, num));
 }
-*/
 
-static int
-bgp_compare_u32(const u32 *x, const u32 *y)
+static inline int
+bgp_originator_id_loopy(struct bgp_proto *p, ea_list *attrs)
 {
-  return (*x < *y) ? -1 : (*x > *y) ? 1 : 0;
+  eattr *e = bgp_find_attr(attrs, BA_ORIGINATOR_ID);
+  return (e && (e->u.data == p->local_id));
 }
 
-static inline void
-bgp_normalize_int_set(u32 *dest, u32 *src, unsigned cnt)
+static inline int
+bgp_cluster_list_loopy(struct bgp_proto *p, ea_list *attrs)
 {
-  memcpy(dest, src, sizeof(u32) * cnt);
-  qsort(dest, cnt, sizeof(u32), (int(*)(const void *, const void *)) bgp_compare_u32);
+  eattr *e = bgp_find_attr(attrs, BA_CLUSTER_LIST);
+  return (e && int_set_contains(e->u.ptr, p->rr_cluster_id));
 }
 
-static int
-bgp_compare_ec(const u32 *xp, const u32 *yp)
+static inline void
+bgp_decode_attr(struct bgp_parse_state *s, uint code, uint flags, byte *data, uint len, ea_list **to)
 {
-  u64 x = ec_get(xp, 0);
-  u64 y = ec_get(yp, 0);
-  return (x < y) ? -1 : (x > y) ? 1 : 0;
+  /* Handle duplicate attributes; RFC 7606 3 (g) */
+  if (BIT32_TEST(s->attrs_seen, code))
+  {
+    if ((code == BA_MP_REACH_NLRI) || (code == BA_MP_UNREACH_NLRI))
+      bgp_parse_error(s, 1);
+    else
+      DISCARD("Discarding duplicate attribute (code %u)", code);
+  }
+  BIT32_SET(s->attrs_seen, code);
+
+  if (bgp_attr_known(code))
+  {
+    const struct bgp_attr_desc *desc = &bgp_attr_table[code];
+
+    /* Handle conflicting flags; RFC 7606 3 (c) */
+    if ((flags ^ desc->flags) & (BAF_OPTIONAL | BAF_TRANSITIVE))
+      WITHDRAW("Malformed %s attribute - conflicting flags (%02x)", desc->name, flags);
+
+    desc->decode(s, code, flags, data, len, to);
+  }
+  else /* Unknown attribute */
+  {
+    if (!(flags & BAF_OPTIONAL))
+      WITHDRAW("Unknown attribute (code %u) - conflicting flags (%02x)", code, flags);
+
+    bgp_decode_unknown(s, code, flags, data, len, to);
+  }
 }
 
-static inline void
-bgp_normalize_ec_set(struct adata *ad, u32 *src, int internal)
+/**
+ * bgp_decode_attrs - check and decode BGP attributes
+ * @s: BGP parse state
+ * @data: start of attribute block
+ * @len: length of attribute block
+ *
+ * This function takes a BGP attribute block (a part of an Update message), checks
+ * its consistency and converts it to a list of BIRD route attributes represented
+ * by an (uncached) &rta.
+ */
+ea_list *
+bgp_decode_attrs(struct bgp_parse_state *s, byte *data, uint len)
 {
-  u32 *dst = int_set_get_data(ad);
+  struct bgp_proto *p = s->proto;
+  ea_list *attrs = NULL;
+  uint code, flags, alen;
+  byte *pos = data;
 
-  /* Remove non-transitive communities (EC_TBIT active) on external sessions */
-  if (! internal)
+  /* Parse the attributes */
+  while (len)
+  {
+    alen = 0;
+
+    /* Read attribute type */
+    if (len < 2)
+      goto framing_error;
+    flags = pos[0];
+    code = pos[1];
+    ADVANCE(pos, len, 2);
+
+    /* Read attribute length */
+    if (flags & BAF_EXT_LEN)
     {
-      int len = int_set_get_size(ad);
-      u32 *t = dst;
-      int i;
-
-      for (i=0; i < len; i += 2)
-	{
-	  if (src[i] & EC_TBIT)
-	    continue;
-	  
-	  *t++ = src[i];
-	  *t++ = src[i+1];
-	}
-
-      ad->length = (t - dst) * 4;
+      if (len < 2)
+	goto framing_error;
+      alen = get_u16(pos);
+      ADVANCE(pos, len, 2);
+    }
+    else
+    {
+      if (len < 1)
+	goto framing_error;
+      alen = *pos;
+      ADVANCE(pos, len, 1);
     }
-  else
-    memcpy(dst, src, ad->length);
 
-  qsort(dst, ad->length / 8, 8, (int(*)(const void *, const void *)) bgp_compare_ec);
-}
+    if (alen > len)
+      goto framing_error;
 
-static int
-bgp_compare_lc(const u32 *x, const u32 *y)
-{
-  if (x[0] != y[0])
-    return (x[0] > y[0]) ? 1 : -1;
-  if (x[1] != y[1])
-    return (x[1] > y[1]) ? 1 : -1;
-  if (x[2] != y[2])
-    return (x[2] > y[2]) ? 1 : -1;
-  return 0;
+    DBG("Attr %02x %02x %u\n", code, flags, alen);
+
+    bgp_decode_attr(s, code, flags, pos, alen, &attrs);
+    ADVANCE(pos, len, alen);
+  }
+
+  if (s->err_withdraw)
+    goto withdraw;
+
+  /* If there is no reachability NLRI, we are finished */
+  if (!s->ip_reach_len && !s->mp_reach_len)
+    return NULL;
+
+
+  /* Handle missing mandatory attributes; RFC 7606 3 (d) */
+  if (!BIT32_TEST(s->attrs_seen, BA_ORIGIN))
+  { REPORT(NO_MANDATORY, "ORIGIN"); goto withdraw; }
+
+  if (!BIT32_TEST(s->attrs_seen, BA_AS_PATH))
+  { REPORT(NO_MANDATORY, "AS_PATH"); goto withdraw; }
+
+  /* When receiving attributes from non-AS4-aware BGP speaker, we have to
+     reconstruct AS_PATH and AGGREGATOR attributes; RFC 6793 4.2.3 */
+  if (!p->as4_session)
+    bgp_process_as4_attrs(&attrs, s->pool);
+
+  /* Reject routes with our ASN in AS_PATH attribute */
+  if (bgp_as_path_loopy(p, attrs, p->local_as))
+    goto withdraw;
+
+  /* Reject routes with our Confederation ID in AS_PATH attribute; RFC 5065 4 */
+  if ((p->public_as != p->local_as) && bgp_as_path_loopy(p, attrs, p->public_as))
+    goto withdraw;
+
+  /* Reject routes with our Router ID in ORIGINATOR_ID attribute; RFC 4456 8 */
+  if (p->is_internal && bgp_originator_id_loopy(p, attrs))
+    goto withdraw;
+
+  /* Reject routes with our Cluster ID in CLUSTER_LIST attribute; RFC 4456 8 */
+  if (p->rr_client && bgp_cluster_list_loopy(p, attrs))
+    goto withdraw;
+
+  /* If there is no local preference, define one */
+  if (!BIT32_TEST(s->attrs_seen, BA_LOCAL_PREF))
+    bgp_set_attr_u32(&attrs, s->pool, BA_LOCAL_PREF, 0, p->cf->default_local_pref);
+
+  return attrs;
+
+
+framing_error:
+  /* RFC 7606 4 - handle attribute framing errors */
+  REPORT("Malformed attribute list - framing error (%u/%u) at %d",
+	 alen, len, (int) (pos - s->attrs));
+
+withdraw:
+  /* RFC 7606 5.2 - handle missing NLRI during errors */
+  if (!s->ip_reach_len && !s->mp_reach_len)
+    bgp_parse_error(s, 1);
+
+  s->err_withdraw = 1;
+  return NULL;
 }
 
-static inline void
-bgp_normalize_lc_set(u32 *dest, u32 *src, unsigned cnt)
+
+/*
+ *	Route bucket hash table
+ */
+
+#define RBH_KEY(b)		b->eattrs, b->hash
+#define RBH_NEXT(b)		b->next
+#define RBH_EQ(a1,h1,a2,h2)	h1 == h2 && ea_same(a1, a2)
+#define RBH_FN(a,h)		h
+
+#define RBH_REHASH		bgp_rbh_rehash
+#define RBH_PARAMS		/8, *2, 2, 2, 8, 20
+
+
+HASH_DEFINE_REHASH_FN(RBH, struct bgp_bucket)
+
+void
+bgp_init_bucket_table(struct bgp_channel *c)
 {
-  memcpy(dest, src, LCOMM_LENGTH * cnt);
-  qsort(dest, cnt, LCOMM_LENGTH, (int(*)(const void *, const void *)) bgp_compare_lc);
-}
+  HASH_INIT(c->bucket_hash, c->pool, 8);
 
-static void
-bgp_rehash_buckets(struct bgp_proto *p)
-{
-  struct bgp_bucket **old = p->bucket_hash;
-  struct bgp_bucket **new;
-  unsigned oldn = p->hash_size;
-  unsigned i, e, mask;
-  struct bgp_bucket *b;
-
-  p->hash_size = p->hash_limit;
-  DBG("BGP: Rehashing bucket table from %d to %d\n", oldn, p->hash_size);
-  p->hash_limit *= 4;
-  if (p->hash_limit >= 65536)
-    p->hash_limit = ~0;
-  new = p->bucket_hash = mb_allocz(p->p.pool, p->hash_size * sizeof(struct bgp_bucket *));
-  mask = p->hash_size - 1;
-  for (i=0; i<oldn; i++)
-    while (b = old[i])
-      {
-	old[i] = b->hash_next;
-	e = b->hash & mask;
-	b->hash_next = new[e];
-	if (b->hash_next)
-	  b->hash_next->hash_prev = b;
-	b->hash_prev = NULL;
-	new[e] = b;
-      }
-  mb_free(old);
+  init_list(&c->bucket_queue);
+  c->withdraw_bucket = NULL;
 }
 
 static struct bgp_bucket *
-bgp_new_bucket(struct bgp_proto *p, ea_list *new, unsigned hash)
+bgp_get_bucket(struct bgp_channel *c, ea_list *new)
 {
-  struct bgp_bucket *b;
-  unsigned ea_size = sizeof(ea_list) + new->count * sizeof(eattr);
-  unsigned ea_size_aligned = BIRD_ALIGN(ea_size, CPU_STRUCT_ALIGN);
-  unsigned size = sizeof(struct bgp_bucket) + ea_size_aligned;
-  unsigned i;
+  /* Hash and lookup */
+  u32 hash = ea_hash(new);
+  struct bgp_bucket *b = HASH_FIND(c->bucket_hash, RBH, new, hash);
+
+  if (b)
+    return b;
+
+  uint ea_size = sizeof(ea_list) + new->count * sizeof(eattr);
+  uint ea_size_aligned = BIRD_ALIGN(ea_size, CPU_STRUCT_ALIGN);
+  uint size = sizeof(struct bgp_bucket) + ea_size_aligned;
+  uint i;
   byte *dest;
-  unsigned index = hash & (p->hash_size - 1);
 
   /* Gather total size of non-inline attributes */
-  for (i=0; i<new->count; i++)
-    {
-      eattr *a = &new->attrs[i];
-      if (!(a->type & EAF_EMBEDDED))
-	size += BIRD_ALIGN(sizeof(struct adata) + a->u.ptr->length, CPU_STRUCT_ALIGN);
-    }
+  for (i = 0; i < new->count; i++)
+  {
+    eattr *a = &new->attrs[i];
 
-  /* Create the bucket and hash it */
-  b = mb_alloc(p->p.pool, size);
-  b->hash_next = p->bucket_hash[index];
-  if (b->hash_next)
-    b->hash_next->hash_prev = b;
-  p->bucket_hash[index] = b;
-  b->hash_prev = NULL;
-  b->hash = hash;
-  add_tail(&p->bucket_queue, &b->send_node);
+    if (!(a->type & EAF_EMBEDDED))
+      size += BIRD_ALIGN(sizeof(struct adata) + a->u.ptr->length, CPU_STRUCT_ALIGN);
+  }
+
+  /* Create the bucket */
+  b = mb_alloc(c->pool, size);
   init_list(&b->prefixes);
+  b->hash = hash;
+
+  /* Copy list of extended attributes */
   memcpy(b->eattrs, new, ea_size);
-  dest = ((byte *)b->eattrs) + ea_size_aligned;
+  dest = ((byte *) b->eattrs) + ea_size_aligned;
 
   /* Copy values of non-inline attributes */
-  for (i=0; i<new->count; i++)
+  for (i = 0; i < new->count; i++)
+  {
+    eattr *a = &b->eattrs->attrs[i];
+
+    if (!(a->type & EAF_EMBEDDED))
     {
-      eattr *a = &b->eattrs->attrs[i];
-      if (!(a->type & EAF_EMBEDDED))
-	{
-	  struct adata *oa = a->u.ptr;
-	  struct adata *na = (struct adata *) dest;
-	  memcpy(na, oa, sizeof(struct adata) + oa->length);
-	  a->u.ptr = na;
-	  dest += BIRD_ALIGN(sizeof(struct adata) + na->length, CPU_STRUCT_ALIGN);
-	}
+      struct adata *oa = a->u.ptr;
+      struct adata *na = (struct adata *) dest;
+      memcpy(na, oa, sizeof(struct adata) + oa->length);
+      a->u.ptr = na;
+      dest += BIRD_ALIGN(sizeof(struct adata) + na->length, CPU_STRUCT_ALIGN);
     }
+  }
 
-  /* If needed, rehash */
-  p->hash_count++;
-  if (p->hash_count > p->hash_limit)
-    bgp_rehash_buckets(p);
+  /* Insert the bucket to send queue and bucket hash */
+  add_tail(&c->bucket_queue, &b->send_node);
+  HASH_INSERT2(c->bucket_hash, RBH, c->pool, b);
 
   return b;
 }
 
 static struct bgp_bucket *
-bgp_get_bucket(struct bgp_proto *p, net *n, ea_list *attrs, int originate)
+bgp_get_withdraw_bucket(struct bgp_channel *c)
 {
-  ea_list *new;
-  unsigned i, cnt, hash, code;
-  eattr *a, *d;
-  u32 seen = 0;
-  struct bgp_bucket *b;
-
-  /* Merge the attribute list */
-  new = alloca(ea_scan(attrs));
-  ea_merge(attrs, new);
-  ea_sort(new);
+  if (!c->withdraw_bucket)
+  {
+    c->withdraw_bucket = mb_allocz(c->pool, sizeof(struct bgp_bucket));
+    init_list(&c->withdraw_bucket->prefixes);
+  }
 
-  /* Normalize attributes */
-  d = new->attrs;
-  cnt = new->count;
-  new->count = 0;
-  for(i=0; i<cnt; i++)
-    {
-      a = &new->attrs[i];
-      if (EA_PROTO(a->id) != EAP_BGP)
-	continue;
-      code = EA_ID(a->id);
-      if (ATTR_KNOWN(code))
-	{
-	  if (!bgp_attr_table[code].allow_in_ebgp && !p->is_internal)
-	    continue;
-	  /* The flags might have been zero if the attr was added by filters */
-	  a->flags = (a->flags & BAF_PARTIAL) | bgp_attr_table[code].expected_flags;
-	  if (code < 32)
-	    seen |= 1 << code;
-	}
-      else
-	{
-	  /* Don't re-export unknown non-transitive attributes */
-	  if (!(a->flags & BAF_TRANSITIVE))
-	    continue;
-	}
-      *d = *a;
-      if ((d->type & EAF_ORIGINATED) && !originate && (d->flags & BAF_TRANSITIVE) && (d->flags & BAF_OPTIONAL))
-	d->flags |= BAF_PARTIAL;
-      switch (d->type & EAF_TYPE_MASK)
-	{
-	case EAF_TYPE_INT_SET:
-	  {
-	    struct adata *z = alloca(sizeof(struct adata) + d->u.ptr->length);
-	    z->length = d->u.ptr->length;
-	    bgp_normalize_int_set((u32 *) z->data, (u32 *) d->u.ptr->data, z->length / 4);
-	    d->u.ptr = z;
-	    break;
-	  }
-	case EAF_TYPE_EC_SET:
-	  {
-	    struct adata *z = alloca(sizeof(struct adata) + d->u.ptr->length);
-	    z->length = d->u.ptr->length;
-	    bgp_normalize_ec_set(z, (u32 *) d->u.ptr->data, p->is_internal);
-	    d->u.ptr = z;
-	    break;
-	  }
-	case EAF_TYPE_LC_SET:
-	  {
-	    struct adata *z = alloca(sizeof(struct adata) + d->u.ptr->length);
-	    z->length = d->u.ptr->length;
-	    bgp_normalize_lc_set((u32 *) z->data, (u32 *) d->u.ptr->data, z->length / LCOMM_LENGTH);
-	    d->u.ptr = z;
-	    break;
-	  }
-	default: ;
-	}
-      d++;
-      new->count++;
-    }
+  return c->withdraw_bucket;
+}
 
-  /* Hash */
-  hash = ea_hash(new);
-  for(b=p->bucket_hash[hash & (p->hash_size - 1)]; b; b=b->hash_next)
-    if (b->hash == hash && ea_same(b->eattrs, new))
-      {
-	DBG("Found bucket.\n");
-	return b;
-      }
-
-  /* Ensure that there are all mandatory attributes */
-  for(i=0; i<ARRAY_SIZE(bgp_mandatory_attrs); i++)
-    if (!(seen & (1 << bgp_mandatory_attrs[i])))
-      {
-	log(L_ERR "%s: Mandatory attribute %s missing in route %I/%d", p->p.name, bgp_attr_table[bgp_mandatory_attrs[i]].name, n->n.prefix, n->n.pxlen);
-	return NULL;
-      }
-
-  /* Check if next hop is valid */
-  a = ea_find(new, EA_CODE(EAP_BGP, BA_NEXT_HOP));
-  if (!a || ipa_equal(p->cf->remote_ip, *(ip_addr *)a->u.ptr->data))
-    {
-      log(L_ERR "%s: Invalid NEXT_HOP attribute in route %I/%d", p->p.name, n->n.prefix, n->n.pxlen);
-      return NULL;
-    }
+void
+bgp_free_bucket(struct bgp_channel *c, struct bgp_bucket *b)
+{
+  rem_node(&b->send_node);
+  HASH_REMOVE2(c->bucket_hash, RBH, c->pool, b);
+  mb_free(b);
+}
 
-  /* Create new bucket */
-  DBG("Creating bucket.\n");
-  return bgp_new_bucket(p, new, hash);
+void
+bgp_defer_bucket(struct bgp_channel *c, struct bgp_bucket *b)
+{
+  rem_node(&b->send_node);
+  add_tail(&c->bucket_queue, &b->send_node);
 }
 
 void
-bgp_free_bucket(struct bgp_proto *p, struct bgp_bucket *buck)
+bgp_withdraw_bucket(struct bgp_channel *c, struct bgp_bucket *b)
 {
-  if (buck->hash_next)
-    buck->hash_next->hash_prev = buck->hash_prev;
-  if (buck->hash_prev)
-    buck->hash_prev->hash_next = buck->hash_next;
-  else
-    p->bucket_hash[buck->hash & (p->hash_size-1)] = buck->hash_next;
-  mb_free(buck);
+  struct bgp_proto *p = (void *) c->c.proto;
+  struct bgp_bucket *wb = bgp_get_withdraw_bucket(c);
+
+  log(L_ERR "%s: Attribute list too long", p->p.name);
+  while (!EMPTY_LIST(b->prefixes))
+  {
+    struct bgp_prefix *px = HEAD(b->prefixes);
+
+    log(L_ERR "%s: - withdrawing %N", p->p.name, &px->net);
+    rem_node(&px->buck_node);
+    add_tail(&wb->prefixes, &px->buck_node);
+  }
 }
 
 
-/* Prefix hash table */
+/*
+ *	Prefix hash table
+ */
 
-#define PXH_KEY(n1)		n1->n.prefix, n1->n.pxlen, n1->path_id
-#define PXH_NEXT(n)		n->next
-#define PXH_EQ(p1,l1,i1,p2,l2,i2) ipa_equal(p1, p2) && l1 == l2 && i1 == i2
-#define PXH_FN(p,l,i)		ipa_hash32(p) ^ u32_hash((l << 16) ^ i)
+#define PXH_KEY(px)		px->net, px->path_id, px->hash
+#define PXH_NEXT(px)		px->next
+#define PXH_EQ(n1,i1,h1,n2,i2,h2) h1 == h2 && i1 == i2 && net_equal(n1, n2)
+#define PXH_FN(n,i,h)		h
 
 #define PXH_REHASH		bgp_pxh_rehash
 #define PXH_PARAMS		/8, *2, 2, 2, 8, 20
@@ -927,282 +1217,235 @@ bgp_free_bucket(struct bgp_proto *p, struct bgp_bucket *buck)
 HASH_DEFINE_REHASH_FN(PXH, struct bgp_prefix)
 
 void
-bgp_init_prefix_table(struct bgp_proto *p, u32 order)
+bgp_init_prefix_table(struct bgp_channel *c)
 {
-  HASH_INIT(p->prefix_hash, p->p.pool, order);
+  HASH_INIT(c->prefix_hash, c->pool, 8);
 
-  p->prefix_slab = sl_new(p->p.pool, sizeof(struct bgp_prefix));
+  c->prefix_slab = sl_new(c->pool, sizeof(struct bgp_prefix) +
+			  net_addr_length[c->c.net_type]);
 }
 
 static struct bgp_prefix *
-bgp_get_prefix(struct bgp_proto *p, ip_addr prefix, int pxlen, u32 path_id)
+bgp_get_prefix(struct bgp_channel *c, net_addr *net, u32 path_id)
 {
-  struct bgp_prefix *bp = HASH_FIND(p->prefix_hash, PXH, prefix, pxlen, path_id);
+  u32 hash = net_hash(net) ^ u32_hash(path_id);
+  struct bgp_prefix *px = HASH_FIND(c->prefix_hash, PXH, net, path_id, hash);
 
-  if (bp)
-    return bp;
+  if (px)
+  {
+    rem_node(&px->buck_node);
+    return px;
+  }
 
-  bp = sl_alloc(p->prefix_slab);
-  bp->n.prefix = prefix;
-  bp->n.pxlen = pxlen;
-  bp->path_id = path_id;
-  bp->bucket_node.next = NULL;
+  px = sl_alloc(c->prefix_slab);
+  px->buck_node.next = NULL;
+  px->buck_node.prev = NULL;
+  px->hash = hash;
+  px->path_id = path_id;
+  net_copy(px->net, net);
 
-  HASH_INSERT2(p->prefix_hash, PXH, p->p.pool, bp);
+  HASH_INSERT2(c->prefix_hash, PXH, c->pool, px);
 
-  return bp;
+  return px;
 }
 
 void
-bgp_free_prefix(struct bgp_proto *p, struct bgp_prefix *bp)
+bgp_free_prefix(struct bgp_channel *c, struct bgp_prefix *px)
 {
-  HASH_REMOVE2(p->prefix_hash, PXH, p->p.pool, bp);
-  sl_free(p->prefix_slab, bp);
+  rem_node(&px->buck_node);
+  HASH_REMOVE2(c->prefix_hash, PXH, c->pool, px);
+  sl_free(c->prefix_slab, px);
 }
 
 
-void
-bgp_rt_notify(struct proto *P, rtable *tbl UNUSED, net *n, rte *new, rte *old UNUSED, ea_list *attrs)
-{
-  struct bgp_proto *p = (struct bgp_proto *) P;
-  struct bgp_bucket *buck;
-  struct bgp_prefix *px;
-  rte *key;
-  u32 path_id;
-
-  DBG("BGP: Got route %I/%d %s\n", n->n.prefix, n->n.pxlen, new ? "up" : "down");
-
-  if (new)
-    {
-      key = new;
-      buck = bgp_get_bucket(p, n, attrs, new->attrs->source != RTS_BGP);
-      if (!buck)			/* Inconsistent attribute list */
-	return;
-    }
-  else
-    {
-      key = old;
-      if (!(buck = p->withdraw_bucket))
-	{
-	  buck = p->withdraw_bucket = mb_alloc(P->pool, sizeof(struct bgp_bucket));
-	  init_list(&buck->prefixes);
-	}
-    }
-  path_id = p->add_path_tx ? key->attrs->src->global_id : 0;
-  px = bgp_get_prefix(p, n->n.prefix, n->n.pxlen, path_id);
-  if (px->bucket_node.next)
-    {
-      DBG("\tRemoving old entry.\n");
-      rem_node(&px->bucket_node);
-    }
-  add_tail(&buck->prefixes, &px->bucket_node);
-  bgp_schedule_packet(p->conn, PKT_UPDATE);
-}
+/*
+ *	BGP protocol glue
+ */
 
-static int
-bgp_create_attrs(struct bgp_proto *p, rte *e, ea_list **attrs, struct linpool *pool)
+int
+bgp_import_control(struct proto *P, rte **new, ea_list **attrs UNUSED, struct linpool *pool UNUSED)
 {
-  ea_list *ea = lp_alloc(pool, sizeof(ea_list) + 4*sizeof(eattr));
-  rta *rta = e->attrs;
-  byte *z;
-
-  ea->next = *attrs;
-  *attrs = ea;
-  ea->flags = EALF_SORTED;
-  ea->count = 4;
-
-  bgp_set_attr(ea->attrs, BA_ORIGIN,
-       ((rta->source == RTS_OSPF_EXT1) || (rta->source == RTS_OSPF_EXT2)) ? ORIGIN_INCOMPLETE : ORIGIN_IGP);
-
-  if (p->is_internal)
-    bgp_set_attr_wa(ea->attrs+1, pool, BA_AS_PATH, 0);
-  else
-    {
-      z = bgp_set_attr_wa(ea->attrs+1, pool, BA_AS_PATH, 6);
-      z[0] = AS_PATH_SEQUENCE;
-      z[1] = 1;				/* 1 AS */
-      put_u32(z+2, p->local_as);
-    }
-
-  /* iBGP -> use gw, eBGP multi-hop -> use source_addr,
-     eBGP single-hop -> use gw if on the same iface */
-  z = bgp_set_attr_wa(ea->attrs+2, pool, BA_NEXT_HOP, NEXT_HOP_LENGTH);
-  if (p->cf->next_hop_self ||
-      rta->dest != RTD_ROUTER ||
-      ipa_equal(rta->gw, IPA_NONE) ||
-      ipa_is_link_local(rta->gw) ||
-      (!p->is_internal && !p->cf->next_hop_keep &&
-       (!p->neigh || (rta->iface != p->neigh->iface))))
-    set_next_hop(z, p->source_addr);
-  else
-    set_next_hop(z, rta->gw);
-
-  bgp_set_attr(ea->attrs+3, BA_LOCAL_PREF, p->cf->default_local_pref);
-
-  return 0;				/* Leave decision to the filters */
-}
+  rte *e = *new;
+  struct proto *SRC = e->attrs->src->proto;
+  struct bgp_proto *p = (struct bgp_proto *) P;
+  struct bgp_proto *src = (SRC->proto == &proto_bgp) ? (struct bgp_proto *) SRC : NULL;
 
+  /* Reject our routes */
+  if (src == p)
+    return -1;
 
-static inline int
-bgp_as_path_loopy(struct bgp_proto *p, rta *a)
-{
-  int num = p->cf->allow_local_as + 1;
-  eattr *e = ea_find(a->eattrs, EA_CODE(EAP_BGP, BA_AS_PATH));
-  return (e && (num > 0) && as_path_contains(e->u.ptr, p->local_as, num));
-}
+  /* Accept non-BGP routes */
+  if (src == NULL)
+    return 0;
 
-static inline int
-bgp_originator_id_loopy(struct bgp_proto *p, rta *a)
-{
-  eattr *e = ea_find(a->eattrs, EA_CODE(EAP_BGP, BA_ORIGINATOR_ID));
-  return (e && (e->u.data == p->local_id));
-}
+  /* IBGP route reflection, RFC 4456 */
+  if (p->is_internal && src->is_internal && (p->local_as == src->local_as))
+  {
+    /* Rejected unless configured as route reflector */
+    if (!p->rr_client && !src->rr_client)
+      return -1;
+
+    /* Generally, this should be handled when path is received, but we check it
+       also here as rr_cluster_id may be undefined or different in src. */
+    if (p->rr_cluster_id && bgp_cluster_list_loopy(p, e->attrs->eattrs))
+      return -1;
+  }
+
+  /* Handle well-known communities, RFC 1997 */
+  struct eattr *c;
+  if (p->cf->interpret_communities &&
+      (c = ea_find(e->attrs->eattrs, EA_CODE(EAP_BGP, BA_COMMUNITY))))
+  {
+    struct adata *d = c->u.ptr;
+
+    /* Do not export anywhere */
+    if (int_set_contains(d, BGP_COMM_NO_ADVERTISE))
+      return -1;
+
+    /* Do not export outside of AS (or member-AS) */
+    if (!p->is_internal && int_set_contains(d, BGP_COMM_NO_EXPORT_SUBCONFED))
+      return -1;
+
+    /* Do not export outside of AS (or confederation) */
+    if (!p->is_interior && int_set_contains(d, BGP_COMM_NO_EXPORT))
+      return -1;
+  }
 
-static inline int
-bgp_cluster_list_loopy(struct bgp_proto *p, rta *a)
-{
-  eattr *e = ea_find(a->eattrs, EA_CODE(EAP_BGP, BA_CLUSTER_LIST));
-  return (e && p->rr_client && int_set_contains(e->u.ptr, p->rr_cluster_id));
+  return 0;
 }
 
+static const adata null_adata;	/* adata of length 0 */
 
 static inline void
-bgp_path_prepend(rte *e, ea_list **attrs, struct linpool *pool, u32 as)
+bgp_path_prepend(ea_list **attrs, struct linpool *pool, int seg, u32 as, int strip)
 {
-  eattr *a = ea_find(e->attrs->eattrs, EA_CODE(EAP_BGP, BA_AS_PATH));
-  bgp_attach_attr(attrs, pool, BA_AS_PATH, (uintptr_t) as_path_prepend(pool, a->u.ptr, as));
+  eattr *a = bgp_find_attr(*attrs, BA_AS_PATH);
+  adata *d = as_path_prepend2(pool, a ? a->u.ptr : &null_adata, seg, as, strip);
+  bgp_set_attr_ptr(attrs, pool, BA_AS_PATH, 0, d);
 }
 
 static inline void
-bgp_cluster_list_prepend(rte *e, ea_list **attrs, struct linpool *pool, u32 cid)
+bgp_cluster_list_prepend(ea_list **attrs, struct linpool *pool, u32 id)
 {
-  eattr *a = ea_find(e->attrs->eattrs, EA_CODE(EAP_BGP, BA_CLUSTER_LIST));
-  bgp_attach_attr(attrs, pool, BA_CLUSTER_LIST, (uintptr_t) int_set_add(pool, a ? a->u.ptr : NULL, cid));
+  eattr *a = bgp_find_attr(*attrs, BA_CLUSTER_LIST);
+  adata *d = int_set_add(pool, a ? a->u.ptr : NULL, id);
+  bgp_set_attr_ptr(attrs, pool, BA_CLUSTER_LIST, 0, d);
 }
 
-static int
-bgp_update_attrs(struct bgp_proto *p, rte *e, ea_list **attrs, struct linpool *pool, int rr)
+static ea_list *
+bgp_update_attrs(struct bgp_proto *p, struct bgp_channel *c, rte *e, ea_list *attrs, struct linpool *pool)
 {
+  struct proto *SRC = e->attrs->src->proto;
+  struct bgp_proto *src = (SRC->proto == &proto_bgp) ? (void *) SRC : NULL;
+  struct bgp_export_state s = { .proto = p, .channel =c, .pool = pool, .src = src, .route = e };
   eattr *a;
 
-  if (!p->is_internal && !p->rs_client)
-    {
-      bgp_path_prepend(e, attrs, pool, p->local_as);
-
-      /* The MULTI_EXIT_DISC attribute received from a neighboring AS MUST NOT be
-       * propagated to other neighboring ASes.
-       * Perhaps it would be better to undefine it.
-       */
-      a = ea_find(e->attrs->eattrs, EA_CODE(EAP_BGP, BA_MULTI_EXIT_DISC));
-      if (a)
-	bgp_attach_attr(attrs, pool, BA_MULTI_EXIT_DISC, 0);
-    }
-
-  /* iBGP -> keep next_hop, eBGP multi-hop -> use source_addr,
-   * eBGP single-hop -> keep next_hop if on the same iface.
-   * If the next_hop is zero (i.e. link-local), keep only if on the same iface.
-   *
-   * Note that same-iface-check uses iface from route, which is based on gw.
-   */
-  a = ea_find(e->attrs->eattrs, EA_CODE(EAP_BGP, BA_NEXT_HOP));
-  if (a && !p->cf->next_hop_self && 
-      (p->cf->next_hop_keep ||
-       (p->is_internal && ipa_nonzero(*((ip_addr *) a->u.ptr->data))) ||
-       (p->neigh && (e->attrs->iface == p->neigh->iface))))
-    {
-      /* Leave the original next hop attribute, will check later where does it point */
-    }
-  else
+  /* ORIGIN attribute - mandatory, attach if missing */
+  if (! bgp_find_attr(attrs, BA_ORIGIN))
+    bgp_set_attr_u32(&attrs, pool, BA_ORIGIN, 0, src ? ORIGIN_INCOMPLETE : ORIGIN_IGP);
+
+  /* AS_PATH attribute - keep or prepend ASN */
+  if (p->is_internal ||
+      (p->rs_client && src && src->rs_client))
+  {
+    /* IBGP or route server -> just ensure there is one */
+    if (! bgp_find_attr(attrs, BA_AS_PATH))
+      bgp_set_attr_ptr(&attrs, pool, BA_AS_PATH, 0, lp_alloc_adata(pool, 0));
+  }
+  else if (p->is_interior)
+  {
+    /* Confederation -> prepend ASN as CONFED_SEQUENCE, keep CONFED_* segments */
+    bgp_path_prepend(&attrs, pool, AS_PATH_CONFED_SEQUENCE, p->public_as, 0);
+  }
+  else /* Regular EBGP (no RS, no confederation) */
+  {
+    /* Regular EBGP -> prepend ASN as regular segment, strip CONFED_* segments */
+    bgp_path_prepend(&attrs, pool, AS_PATH_SEQUENCE, p->public_as, 1);
+
+    /* MULTI_EXIT_DESC attribute - accept only if set in export filter */
+    a = bgp_find_attr(attrs, BA_MULTI_EXIT_DISC);
+    if (a && !(a->type & EAF_FRESH))
+      bgp_unset_attr(&attrs, pool, BA_MULTI_EXIT_DISC);
+  }
+
+  /* NEXT_HOP attribute - delegated to AF-specific hook */
+  a = bgp_find_attr(attrs, BA_NEXT_HOP);
+  bgp_update_next_hop(&s, a, &attrs);
+
+  /* LOCAL_PREF attribute - required for IBGP, attach if missing */
+  if (p->is_interior && ! bgp_find_attr(attrs, BA_LOCAL_PREF))
+    bgp_set_attr_u32(&attrs, pool, BA_LOCAL_PREF, 0, p->cf->default_local_pref);
+
+  /* IBGP route reflection, RFC 4456 */
+  if (src && src->is_internal && p->is_internal && (src->local_as == p->local_as))
+  {
+    /* ORIGINATOR_ID attribute - attach if not already set */
+    if (! bgp_find_attr(attrs, BA_ORIGINATOR_ID))
+      bgp_set_attr_u32(&attrs, pool, BA_ORIGINATOR_ID, 0, src->remote_id);
+
+    /* CLUSTER_LIST attribute - prepend cluster ID */
+    if (src->rr_cluster_id)
+      bgp_cluster_list_prepend(&attrs, pool, src->rr_cluster_id);
+
+    /* Handle different src and dst cluster ID - prepend both ones */
+    if (p->rr_cluster_id && (src->rr_cluster_id != p->rr_cluster_id))
+      bgp_cluster_list_prepend(&attrs, pool, p->rr_cluster_id);
+  }
+
+  /* AS4_* transition attributes, RFC 6793 4.2.2 */
+  if (! p->as4_session)
+  {
+    a = bgp_find_attr(attrs, BA_AS_PATH);
+    if (a && as_path_contains_as4(a->u.ptr))
     {
-      /* Need to create new one */
-      byte *b = bgp_attach_attr_wa(attrs, pool, BA_NEXT_HOP, NEXT_HOP_LENGTH);
-      set_next_hop(b, p->source_addr);
+      bgp_set_attr_ptr(&attrs, pool, BA_AS_PATH, 0, as_path_to_old(pool, a->u.ptr));
+      bgp_set_attr_ptr(&attrs, pool, BA_AS4_PATH, 0, as_path_strip_confed(pool, a->u.ptr));
     }
 
-  if (rr)
+    a = bgp_find_attr(attrs, BA_AGGREGATOR);
+    if (a && aggregator_contains_as4(a->u.ptr))
     {
-      /* Handling route reflection, RFC 4456 */
-      struct bgp_proto *src = (struct bgp_proto *) e->attrs->src->proto;
-
-      a = ea_find(e->attrs->eattrs, EA_CODE(EAP_BGP, BA_ORIGINATOR_ID));
-      if (!a)
-	bgp_attach_attr(attrs, pool, BA_ORIGINATOR_ID, src->remote_id);
-
-      /* We attach proper cluster ID according to whether the route is entering or leaving the cluster */
-      bgp_cluster_list_prepend(e, attrs, pool, src->rr_client ? src->rr_cluster_id : p->rr_cluster_id);
-
-      /* Two RR clients with different cluster ID, hmmm */
-      if (src->rr_client && p->rr_client && (src->rr_cluster_id != p->rr_cluster_id))
-	bgp_cluster_list_prepend(e, attrs, pool, p->rr_cluster_id);
+      bgp_set_attr_ptr(&attrs, pool, BA_AGGREGATOR, 0, aggregator_to_old(pool, a->u.ptr));
+      bgp_set_attr_ptr(&attrs, pool, BA_AS4_AGGREGATOR, 0, a->u.ptr);
     }
+  }
 
-  return 0;				/* Leave decision to the filters */
+  /* Apply per-attribute export hooks for validatation and normalization */
+  return bgp_export_attrs(&s, attrs);
 }
 
-static int
-bgp_community_filter(struct bgp_proto *p, rte *e)
+void
+bgp_rt_notify(struct proto *P, struct channel *C, net *n, rte *new, rte *old, ea_list *attrs)
 {
-  eattr *a;
-  struct adata *d;
-
-  /* Check if we aren't forbidden to export the route by communities */
-  a = ea_find(e->attrs->eattrs, EA_CODE(EAP_BGP, BA_COMMUNITY));
-  if (a)
-    {
-      d = a->u.ptr;
-      if (int_set_contains(d, BGP_COMM_NO_ADVERTISE))
-	{
-	  DBG("\tNO_ADVERTISE\n");
-	  return 1;
-	}
-      if (!p->is_internal &&
-	  (int_set_contains(d, BGP_COMM_NO_EXPORT) ||
-	   int_set_contains(d, BGP_COMM_NO_EXPORT_SUBCONFED)))
-	{
-	  DBG("\tNO_EXPORT\n");
-	  return 1;
-	}
-    }
+  struct bgp_proto *p = (void *) P;
+  struct bgp_channel *c = (void *) C;
+  struct bgp_bucket *buck;
+  struct bgp_prefix *px;
+  u32 path;
 
-  return 0;
-}
+  if (new)
+  {
+    attrs = bgp_update_attrs(p, c, new, attrs, bgp_linpool);
 
-int
-bgp_import_control(struct proto *P, rte **new, ea_list **attrs, struct linpool *pool)
-{
-  rte *e = *new;
-  struct bgp_proto *p = (struct bgp_proto *) P;
-  struct bgp_proto *new_bgp = (e->attrs->src->proto->proto == &proto_bgp) ?
-    (struct bgp_proto *) e->attrs->src->proto : NULL;
+    /* If attributes are invalid, we fail back to withdraw */
+    buck = attrs ? bgp_get_bucket(c, attrs) : bgp_get_withdraw_bucket(c);
+    path = new->attrs->src->global_id;
 
-  if (p == new_bgp)			/* Poison reverse updates */
-    return -1;
-  if (new_bgp)
-    {
-      /* We should check here for cluster list loop, because the receiving BGP instance
-	 might have different cluster ID  */
-      if (bgp_cluster_list_loopy(p, e->attrs))
-	return -1;
-
-      if (p->cf->interpret_communities && bgp_community_filter(p, e))
-	return -1;
-
-      if (p->local_as == new_bgp->local_as && p->is_internal && new_bgp->is_internal)
-	{
-	  /* Redistribution of internal routes with IBGP */
-	  if (p->rr_client || new_bgp->rr_client)
-	    /* Route reflection, RFC 4456 */
-	    return bgp_update_attrs(p, e, attrs, pool, 1);
-	  else
-	    return -1;
-	}
-      else
-	return bgp_update_attrs(p, e, attrs, pool, 0);
-    }
+    lp_flush(bgp_linpool);
+  }
   else
-    return bgp_create_attrs(p, e, attrs, pool);
+  {
+    buck = bgp_get_withdraw_bucket(c);
+    path = old->attrs->src->global_id;
+  }
+
+  px = bgp_get_prefix(c, n->n.addr, c->add_path_tx ? path : 0);
+  add_tail(&buck->prefixes, &px->buck_node);
+
+  bgp_schedule_packet(p->conn, c, PKT_UPDATE);
 }
 
+
 static inline u32
 bgp_get_neighbor(rte *r)
 {
@@ -1218,7 +1461,7 @@ bgp_get_neighbor(rte *r)
 static inline int
 rte_resolvable(rte *rt)
 {
-  int rd = rt->attrs->dest;  
+  int rd = rt->attrs->dest;
   return (rd == RTD_ROUTER) || (rd == RTD_DEVICE) || (rd == RTD_MULTIPATH);
 }
 
@@ -1258,16 +1501,16 @@ bgp_rte_better(rte *new, rte *old)
 
   /* RFC 4271 9.1.2.2. a)  Use AS path lengths */
   if (new_bgp->cf->compare_path_lengths || old_bgp->cf->compare_path_lengths)
-    {
-      x = ea_find(new->attrs->eattrs, EA_CODE(EAP_BGP, BA_AS_PATH));
-      y = ea_find(old->attrs->eattrs, EA_CODE(EAP_BGP, BA_AS_PATH));
-      n = x ? as_path_getlen(x->u.ptr) : AS_PATH_MAXLEN;
-      o = y ? as_path_getlen(y->u.ptr) : AS_PATH_MAXLEN;
-      if (n < o)
-	return 1;
-      if (n > o)
-	return 0;
-    }
+  {
+    x = ea_find(new->attrs->eattrs, EA_CODE(EAP_BGP, BA_AS_PATH));
+    y = ea_find(old->attrs->eattrs, EA_CODE(EAP_BGP, BA_AS_PATH));
+    n = x ? as_path_getlen(x->u.ptr) : AS_PATH_MAXLEN;
+    o = y ? as_path_getlen(y->u.ptr) : AS_PATH_MAXLEN;
+    if (n < o)
+      return 1;
+    if (n > o)
+      return 0;
+  }
 
   /* RFC 4271 9.1.2.2. b) Use origins */
   x = ea_find(new->attrs->eattrs, EA_CODE(EAP_BGP, BA_ORIGIN));
@@ -1292,21 +1535,21 @@ bgp_rte_better(rte *new, rte *old)
    */
   if (new_bgp->cf->med_metric || old_bgp->cf->med_metric ||
       (bgp_get_neighbor(new) == bgp_get_neighbor(old)))
-    {
-      x = ea_find(new->attrs->eattrs, EA_CODE(EAP_BGP, BA_MULTI_EXIT_DISC));
-      y = ea_find(old->attrs->eattrs, EA_CODE(EAP_BGP, BA_MULTI_EXIT_DISC));
-      n = x ? x->u.data : new_bgp->cf->default_med;
-      o = y ? y->u.data : old_bgp->cf->default_med;
-      if (n < o)
-	return 1;
-      if (n > o)
-	return 0;
-    }
+  {
+    x = ea_find(new->attrs->eattrs, EA_CODE(EAP_BGP, BA_MULTI_EXIT_DISC));
+    y = ea_find(old->attrs->eattrs, EA_CODE(EAP_BGP, BA_MULTI_EXIT_DISC));
+    n = x ? x->u.data : new_bgp->cf->default_med;
+    o = y ? y->u.data : old_bgp->cf->default_med;
+    if (n < o)
+      return 1;
+    if (n > o)
+      return 0;
+  }
 
   /* RFC 4271 9.1.2.2. d) Prefer external peers */
-  if (new_bgp->is_internal > old_bgp->is_internal)
+  if (new_bgp->is_interior > old_bgp->is_interior)
     return 0;
-  if (new_bgp->is_internal < old_bgp->is_internal)
+  if (new_bgp->is_interior < old_bgp->is_interior)
     return 1;
 
   /* RFC 4271 9.1.2.2. e) Compare IGP metrics */
@@ -1318,7 +1561,7 @@ bgp_rte_better(rte *new, rte *old)
     return 0;
 
   /* RFC 4271 9.1.2.2. f) Compare BGP identifiers */
-  /* RFC 4456 9. a) Use ORIGINATOR_ID instead of local neighor ID */
+  /* RFC 4456 9. a) Use ORIGINATOR_ID instead of local neighbor ID */
   x = ea_find(new->attrs->eattrs, EA_CODE(EAP_BGP, BA_ORIGINATOR_ID));
   y = ea_find(old->attrs->eattrs, EA_CODE(EAP_BGP, BA_ORIGINATOR_ID));
   n = x ? x->u.data : new_bgp->remote_id;
@@ -1377,18 +1620,18 @@ bgp_rte_mergable(rte *pri, rte *sec)
 
   /* RFC 4271 9.1.2.2. a)  Use AS path lengths */
   if (pri_bgp->cf->compare_path_lengths || sec_bgp->cf->compare_path_lengths)
-    {
-      x = ea_find(pri->attrs->eattrs, EA_CODE(EAP_BGP, BA_AS_PATH));
-      y = ea_find(sec->attrs->eattrs, EA_CODE(EAP_BGP, BA_AS_PATH));
-      p = x ? as_path_getlen(x->u.ptr) : AS_PATH_MAXLEN;
-      s = y ? as_path_getlen(y->u.ptr) : AS_PATH_MAXLEN;
+  {
+    x = ea_find(pri->attrs->eattrs, EA_CODE(EAP_BGP, BA_AS_PATH));
+    y = ea_find(sec->attrs->eattrs, EA_CODE(EAP_BGP, BA_AS_PATH));
+    p = x ? as_path_getlen(x->u.ptr) : AS_PATH_MAXLEN;
+    s = y ? as_path_getlen(y->u.ptr) : AS_PATH_MAXLEN;
 
-      if (p != s)
-	return 0;
+    if (p != s)
+      return 0;
 
-//      if (DELTA(p, s) > pri_bgp->cf->relax_multipath)
-//	return 0;
-    }
+//    if (DELTA(p, s) > pri_bgp->cf->relax_multipath)
+//      return 0;
+  }
 
   /* RFC 4271 9.1.2.2. b) Use origins */
   x = ea_find(pri->attrs->eattrs, EA_CODE(EAP_BGP, BA_ORIGIN));
@@ -1401,14 +1644,14 @@ bgp_rte_mergable(rte *pri, rte *sec)
   /* RFC 4271 9.1.2.2. c) Compare MED's */
   if (pri_bgp->cf->med_metric || sec_bgp->cf->med_metric ||
       (bgp_get_neighbor(pri) == bgp_get_neighbor(sec)))
-    {
-      x = ea_find(pri->attrs->eattrs, EA_CODE(EAP_BGP, BA_MULTI_EXIT_DISC));
-      y = ea_find(sec->attrs->eattrs, EA_CODE(EAP_BGP, BA_MULTI_EXIT_DISC));
-      p = x ? x->u.data : pri_bgp->cf->default_med;
-      s = y ? y->u.data : sec_bgp->cf->default_med;
-      if (p != s)
-	return 0;
-    }
+  {
+    x = ea_find(pri->attrs->eattrs, EA_CODE(EAP_BGP, BA_MULTI_EXIT_DISC));
+    y = ea_find(sec->attrs->eattrs, EA_CODE(EAP_BGP, BA_MULTI_EXIT_DISC));
+    p = x ? x->u.data : pri_bgp->cf->default_med;
+    s = y ? y->u.data : sec_bgp->cf->default_med;
+    if (p != s)
+      return 0;
+  }
 
   /* RFC 4271 9.1.2.2. d) Prefer external peers */
   if (pri_bgp->is_internal != sec_bgp->is_internal)
@@ -1426,7 +1669,6 @@ bgp_rte_mergable(rte *pri, rte *sec)
 }
 
 
-
 static inline int
 same_group(rte *r, u32 lpref, u32 lasn)
 {
@@ -1471,7 +1713,7 @@ bgp_rte_recalculate(rtable *table, net *net, rte *new, rte *old, rte *old_best)
    * that this fn is not called for them.
    *
    * The idea is simple, the implementation is more problematic,
-   * mostly because of optimizations in rte_recalculate() that 
+   * mostly because of optimizations in rte_recalculate() that
    * avoids full recalculation in most cases.
    *
    * We can assume that at least one of new, old is non-NULL and both
@@ -1483,14 +1725,14 @@ bgp_rte_recalculate(rtable *table, net *net, rte *new, rte *old, rte *old_best)
   /* If new and old are from different groups, we just process that
      as two independent events */
   if (new && old && !same_group(old, lpref, lasn))
-    {
-      int i1, i2;
-      i1 = bgp_rte_recalculate(table, net, NULL, old, old_best);
-      i2 = bgp_rte_recalculate(table, net, new, NULL, old_best);
-      return i1 || i2;
-    }
+  {
+    int i1, i2;
+    i1 = bgp_rte_recalculate(table, net, NULL, old, old_best);
+    i2 = bgp_rte_recalculate(table, net, new, NULL, old_best);
+    return i1 || i2;
+  }
 
-  /* 
+  /*
    * We could find the best-in-group and then make some shortcuts like
    * in rte_recalculate, but as we would have to walk through all
    * net->routes just to find it, it is probably not worth. So we
@@ -1502,35 +1744,35 @@ bgp_rte_recalculate(rtable *table, net *net, rte *new, rte *old, rte *old_best)
     new->u.bgp.suppressed = 1;
 
   if (old)
+  {
+    old_is_group_best = !old->u.bgp.suppressed;
+    old->u.bgp.suppressed = 1;
+    int new_is_better = new && bgp_rte_better(new, old);
+
+    /* The first case - replace not best with worse (or remove not best) */
+    if (!old_is_group_best && !new_is_better)
+      return 0;
+
+    /* The second case - replace the best with better */
+    if (old_is_group_best && new_is_better)
     {
-      old_is_group_best = !old->u.bgp.suppressed;
-      old->u.bgp.suppressed = 1;
-      int new_is_better = new && bgp_rte_better(new, old);
-
-      /* The first case - replace not best with worse (or remove not best) */
-      if (!old_is_group_best && !new_is_better)
-	return 0;
-
-      /* The second case - replace the best with better */
-      if (old_is_group_best && new_is_better)
-	{
-	  /* new is best-in-group, the see discussion below - this is
-	     a special variant of NBG && OBG. From OBG we can deduce
-	     that same_group(old_best) iff (old == old_best)  */
-	  new->u.bgp.suppressed = 0;
-	  return (old == old_best);
-	}
+      /* new is best-in-group, the see discussion below - this is
+	 a special variant of NBG && OBG. From OBG we can deduce
+	 that same_group(old_best) iff (old == old_best)  */
+      new->u.bgp.suppressed = 0;
+      return (old == old_best);
     }
+  }
 
   /* The default case - find a new best-in-group route */
   r = new; /* new may not be in the list */
   for (s=net->routes; rte_is_valid(s); s=s->next)
     if (use_deterministic_med(s) && same_group(s, lpref, lasn))
-      {
-	s->u.bgp.suppressed = 1;
-	if (!r || bgp_rte_better(s, r))
-	  r = s;
-      }
+    {
+      s->u.bgp.suppressed = 1;
+      if (!r || bgp_rte_better(s, r))
+	r = s;
+    }
 
   /* Simple case - the last route in group disappears */
   if (!r)
@@ -1569,378 +1811,79 @@ bgp_rte_recalculate(rtable *table, net *net, rte *new, rte *old, rte *old_best)
     return old_is_group_best;
 }
 
-static struct adata *
-bgp_aggregator_convert_to_new(struct adata *old, struct linpool *pool)
-{
-  struct adata *newa = lp_alloc(pool, sizeof(struct adata) + 8);
-  newa->length = 8;
-  aggregator_convert_to_new(old, newa->data);
-  return newa;
-}
-
 
-/* Take last req_as ASNs from path old2 (in 2B format), convert to 4B format
- * and append path old4 (in 4B format).
+/*
+ * Reconstruct AS_PATH and AGGREGATOR according to RFC 6793 4.2.3
  */
-static struct adata *
-bgp_merge_as_paths(struct adata *old2, struct adata *old4, int req_as, struct linpool *pool)
-{
-  byte buf[old2->length * 2];
-
-  int ol = as_path_convert_to_new(old2, buf, req_as);
-  int nl = ol + (old4 ? old4->length : 0);
-
-  struct adata *newa = lp_alloc(pool, sizeof(struct adata) + nl);
-  newa->length = nl;
-  memcpy(newa->data, buf, ol);
-  if (old4) memcpy(newa->data + ol, old4->data, old4->length);
-
-  return newa;
-}
-
-static int
-as4_aggregator_valid(struct adata *aggr)
-{
-  return aggr->length == 8;
-}
-
-
-/* Reconstruct 4B AS_PATH and AGGREGATOR according to RFC 4893 4.2.3 */
-static void
-bgp_reconstruct_4b_atts(struct bgp_proto *p, rta *a, struct linpool *pool)
-{
-  eattr *p2 =ea_find(a->eattrs, EA_CODE(EAP_BGP, BA_AS_PATH));
-  eattr *p4 =ea_find(a->eattrs, EA_CODE(EAP_BGP, BA_AS4_PATH));
-  eattr *a2 =ea_find(a->eattrs, EA_CODE(EAP_BGP, BA_AGGREGATOR));
-  eattr *a4 =ea_find(a->eattrs, EA_CODE(EAP_BGP, BA_AS4_AGGREGATOR));
-  int a4_removed = 0;
-
-  if (a4 && !as4_aggregator_valid(a4->u.ptr))
-    {
-      log(L_WARN "%s: AS4_AGGREGATOR attribute is invalid, skipping attribute", p->p.name);
-      a4 = NULL;
-      a4_removed = 1;
-    }
-
-  if (a2)
-    {
-      u32 a2_as = get_u16(a2->u.ptr->data);
-
-      if (a4)
-	{
-	  if (a2_as != AS_TRANS)
-	    {
-	      /* Routes were aggregated by old router and therefore AS4_PATH
-	       * and AS4_AGGREGATOR is invalid
-	       *
-	       * Convert AS_PATH and AGGREGATOR to 4B format and finish.
-	       */
-
-	      a2->u.ptr = bgp_aggregator_convert_to_new(a2->u.ptr, pool);
-	      p2->u.ptr = bgp_merge_as_paths(p2->u.ptr, NULL, AS_PATH_MAXLEN, pool);
-
-	      return;
-	    }
-	  else
-	    {
-	      /* Common case, use AS4_AGGREGATOR attribute */
-	      a2->u.ptr = a4->u.ptr;
-	    }
-	}
-      else
-	{
-	  /* Common case, use old AGGREGATOR attribute */
-	  a2->u.ptr = bgp_aggregator_convert_to_new(a2->u.ptr, pool);
-
-	  if ((a2_as == AS_TRANS) && !a4_removed)
-	    log(L_WARN "%s: AGGREGATOR attribute contain AS_TRANS, but AS4_AGGREGATOR is missing", p->p.name);
-	}
-    }
-  else
-    if (a4)
-      log(L_WARN "%s: AS4_AGGREGATOR attribute received, but AGGREGATOR attribute is missing", p->p.name);
-
-  int p2_len = as_path_getlen_int(p2->u.ptr, 2);
-  int p4_len = p4 ? validate_as4_path(p, p4->u.ptr) : -1;
-
-  if (p4 && (p4_len < 0))
-    log(L_WARN "%s: AS4_PATH attribute is malformed, skipping attribute", p->p.name);
-
-  if ((p4_len <= 0) || (p2_len < p4_len))
-    p2->u.ptr = bgp_merge_as_paths(p2->u.ptr, NULL, AS_PATH_MAXLEN, pool);
-  else
-    p2->u.ptr = bgp_merge_as_paths(p2->u.ptr, p4->u.ptr, p2_len - p4_len, pool);
-}
-
 static void
-bgp_remove_as4_attrs(struct bgp_proto *p, rta *a)
+bgp_process_as4_attrs(ea_list **attrs, struct linpool *pool)
 {
-  unsigned id1 = EA_CODE(EAP_BGP, BA_AS4_PATH);
-  unsigned id2 = EA_CODE(EAP_BGP, BA_AS4_AGGREGATOR);
-  ea_list **el = &(a->eattrs);
+  eattr *p2 = bgp_find_attr(*attrs, BA_AS_PATH);
+  eattr *p4 = bgp_find_attr(*attrs, BA_AS4_PATH);
+  eattr *a2 = bgp_find_attr(*attrs, BA_AGGREGATOR);
+  eattr *a4 = bgp_find_attr(*attrs, BA_AS4_AGGREGATOR);
 
-  /* We know that ea_lists constructed in bgp_decode attrs have one attribute per ea_list struct */
-  while (*el != NULL)
-    {
-      unsigned fid = (*el)->attrs[0].id;
-
-      if ((fid == id1) || (fid == id2))
-	{
-	  *el = (*el)->next;
-	  if (p->as4_session)
-	    log(L_WARN "%s: Unexpected AS4_* attributes received", p->p.name);
-	}
-      else
-	el = &((*el)->next);
-    }
-}
+  /* First, unset AS4_* attributes */
+  if (p4) bgp_unset_attr(attrs, pool, BA_AS4_PATH);
+  if (a4) bgp_unset_attr(attrs, pool, BA_AS4_AGGREGATOR);
 
-/**
- * bgp_decode_attrs - check and decode BGP attributes
- * @conn: connection
- * @attr: start of attribute block
- * @len: length of attribute block
- * @pool: linear pool to make all the allocations in
- * @mandatory: 1 iff presence of mandatory attributes has to be checked
- *
- * This function takes a BGP attribute block (a part of an Update message), checks
- * its consistency and converts it to a list of BIRD route attributes represented
- * by a &rta.
- */
-struct rta *
-bgp_decode_attrs(struct bgp_conn *conn, byte *attr, uint len, struct linpool *pool, int mandatory)
-{
-  struct bgp_proto *bgp = conn->bgp;
-  rta *a = lp_alloc(pool, sizeof(struct rta));
-  uint flags, code, l, i, type;
-  int errcode;
-  byte *z, *attr_start;
-  byte seen[256/8];
-  ea_list *ea;
-  struct adata *ad;
-  int withdraw = 0;
-
-  bzero(a, sizeof(rta));
-  a->source = RTS_BGP;
-  a->scope = SCOPE_UNIVERSE;
-  a->cast = RTC_UNICAST;
-  /* a->dest = RTD_ROUTER;  -- set in bgp_set_next_hop() */
-  a->from = bgp->cf->remote_ip;
+  /* Handle AGGREGATOR attribute */
+  if (a2 && a4)
+  {
+    u32 a2_asn = get_u32(a2->u.ptr->data);
 
-  /* Parse the attributes */
-  bzero(seen, sizeof(seen));
-  DBG("BGP: Parsing attributes\n");
-  while (len)
-    {
-      if (len < 2)
-	goto malformed;
-      attr_start = attr;
-      flags = *attr++;
-      code = *attr++;
-      len -= 2;
-      if (flags & BAF_EXT_LEN)
-	{
-	  if (len < 2)
-	    goto malformed;
-	  l = get_u16(attr);
-	  attr += 2;
-	  len -= 2;
-	}
-      else
-	{
-	  if (len < 1)
-	    goto malformed;
-	  l = *attr++;
-	  len--;
-	}
-      if (l > len)
-	goto malformed;
-      len -= l;
-      z = attr;
-      attr += l;
-      DBG("Attr %02x %02x %d\n", code, flags, l);
-      if (seen[code/8] & (1 << (code%8)))
-	goto malformed;
-      if (ATTR_KNOWN(code))
-	{
-	  struct attr_desc *desc = &bgp_attr_table[code];
-	  if (desc->expected_length >= 0 && desc->expected_length != (int) l)
-	    { errcode = 5; goto err; }
-	  if ((desc->expected_flags ^ flags) & (BAF_OPTIONAL | BAF_TRANSITIVE))
-	    { errcode = 4; goto err; }
-	  if (!desc->allow_in_ebgp && !bgp->is_internal)
-	    continue;
-	  if (desc->validate)
-	    {
-	      errcode = desc->validate(bgp, z, l);
-	      if (errcode > 0)
-		goto err;
-	      if (errcode == IGNORE)
-		continue;
-	      if (errcode <= WITHDRAW)
-		{
-		  log(L_WARN "%s: Attribute %s is malformed, withdrawing update",
-		      bgp->p.name, desc->name);
-		  withdraw = 1;
-		}
-	    }
-	  else if (code == BA_AS_PATH)
-	    {
-	      /* Special case as it might also trim the attribute */
-	      if (validate_as_path(bgp, z, &l) < 0)
-		{ errcode = 11; goto err; }
-	    }
-	  type = desc->type;
-	}
-      else				/* Unknown attribute */
-	{
-	  if (!(flags & BAF_OPTIONAL))
-	    { errcode = 2; goto err; }
-	  type = EAF_TYPE_OPAQUE;
-	}
-      
-      // Only OPTIONAL and TRANSITIVE attributes may have non-zero PARTIAL flag
-      // if (!((flags & BAF_OPTIONAL) && (flags & BAF_TRANSITIVE)) && (flags & BAF_PARTIAL))
-      //   { errcode = 4; goto err; }
-
-      seen[code/8] |= (1 << (code%8));
-      ea = lp_alloc(pool, sizeof(ea_list) + sizeof(eattr));
-      ea->next = a->eattrs;
-      a->eattrs = ea;
-      ea->flags = 0;
-      ea->count = 1;
-      ea->attrs[0].id = EA_CODE(EAP_BGP, code);
-      ea->attrs[0].flags = flags;
-      ea->attrs[0].type = type;
-      if (type & EAF_EMBEDDED)
-	ad = NULL;
-      else
-	{
-	  ad = lp_alloc(pool, sizeof(struct adata) + l);
-	  ea->attrs[0].u.ptr = ad;
-	  ad->length = l;
-	  memcpy(ad->data, z, l);
-	}
-      switch (type)
-	{
-	case EAF_TYPE_ROUTER_ID:
-	case EAF_TYPE_INT:
-	  if (l == 1)
-	    ea->attrs[0].u.data = *z;
-	  else
-	    ea->attrs[0].u.data = get_u32(z);
-	  break;
-	case EAF_TYPE_IP_ADDRESS:
-	  ipa_ntoh(*(ip_addr *)ad->data);
-	  break;
-	case EAF_TYPE_INT_SET:
-	case EAF_TYPE_LC_SET:
-	case EAF_TYPE_EC_SET:
-	  {
-	    u32 *z = (u32 *) ad->data;
-	    for(i=0; i<ad->length/4; i++)
-	      z[i] = ntohl(z[i]);
-	    break;
-	  }
-	}
-    }
-
-  if (withdraw)
-    goto withdraw;
-
-#ifdef IPV6
-  /* If we received MP_REACH_NLRI we should check mandatory attributes */
-  if (bgp->mp_reach_len != 0)
-    mandatory = 1;
-#endif
-
-  /* If there is no (reachability) NLRI, we should exit now */
-  if (! mandatory)
-    return a;
-
-  /* Check if all mandatory attributes are present */
-  for(i=0; i < ARRAY_SIZE(bgp_mandatory_attrs); i++)
-    {
-      code = bgp_mandatory_attrs[i];
-      if (!(seen[code/8] & (1 << (code%8))))
-	{
-	  bgp_error(conn, 3, 3, &bgp_mandatory_attrs[i], 1);
-	  return NULL;
-	}
-    }
-
-  /* When receiving attributes from non-AS4-aware BGP speaker,
-   * we have to reconstruct 4B AS_PATH and AGGREGATOR attributes
-   */
-  if (! bgp->as4_session)
-    bgp_reconstruct_4b_atts(bgp, a, pool);
-
-  bgp_remove_as4_attrs(bgp, a);
-
-  /* If the AS path attribute contains our AS, reject the routes */
-  if (bgp_as_path_loopy(bgp, a))
-    goto withdraw;
-
-  /* Two checks for IBGP loops caused by route reflection, RFC 4456 */ 
-  if (bgp_originator_id_loopy(bgp, a) ||
-      bgp_cluster_list_loopy(bgp, a))
-    goto withdraw;
-
-  /* If there's no local preference, define one */
-  if (!(seen[0] & (1 << BA_LOCAL_PREF)))
-    bgp_attach_attr(&a->eattrs, pool, BA_LOCAL_PREF, bgp->cf->default_local_pref);
+    /* If routes were aggregated by an old router, then AS4_PATH and
+       AS4_AGGREGATOR are invalid. In that case we give up. */
+    if (a2_asn != AS_TRANS)
+      return;
 
-  return a;
+    /* Use AS4_AGGREGATOR instead of AGGREGATOR */
+    a2->u.ptr = a4->u.ptr;
+  }
 
-withdraw:
-  return NULL;
+  /* Handle AS_PATH attribute */
+  if (p2 && p4)
+  {
+    int p2_len = as_path_getlen(p2->u.ptr);
+    int p4_len = as_path_getlen(p4->u.ptr);
 
-malformed:
-  bgp_error(conn, 3, 1, NULL, 0);
-  return NULL;
+    /* AS_PATH is too short, give up */
+    if (p2_len < p4_len)
+      return;
 
-err:
-  bgp_error(conn, 3, errcode, attr_start, z+l-attr_start);
-  return NULL;
+    /* Merge AS_PATH and AS4_PATH */
+    as_path_cut(p2->u.ptr, p2_len - p4_len);
+    p2->u.ptr = as_path_merge(pool, p2->u.ptr, p4->u.ptr);
+  }
 }
 
 int
 bgp_get_attr(eattr *a, byte *buf, int buflen)
 {
   uint i = EA_ID(a->id);
-  struct attr_desc *d;
+  const struct bgp_attr_desc *d;
   int len;
 
-  if (ATTR_KNOWN(i))
+  if (bgp_attr_known(i))
+  {
+    d = &bgp_attr_table[i];
+    len = bsprintf(buf, "%s", d->name);
+    buf += len;
+    if (d->format)
     {
-      d = &bgp_attr_table[i];
-      len = bsprintf(buf, "%s", d->name);
-      buf += len;
-      if (d->format)
-	{
-	  *buf++ = ':';
-	  *buf++ = ' ';
-	  d->format(a, buf, buflen - len - 2);
-	  return GA_FULL;
-	}
-      return GA_NAME;
+      *buf++ = ':';
+      *buf++ = ' ';
+      d->format(a, buf, buflen - len - 2);
+      return GA_FULL;
     }
+    return GA_NAME;
+  }
+
   bsprintf(buf, "%02x%s", i, (a->flags & BAF_TRANSITIVE) ? " [t]" : "");
   return GA_NAME;
 }
 
 void
-bgp_init_bucket_table(struct bgp_proto *p)
-{
-  p->hash_size = 256;
-  p->hash_limit = p->hash_size * 4;
-  p->bucket_hash = mb_allocz(p->p.pool, p->hash_size * sizeof(struct bgp_bucket *));
-  init_list(&p->bucket_queue);
-  p->withdraw_bucket = NULL;
-  // fib_init(&p->prefix_fib, p->p.pool, sizeof(struct bgp_prefix), 0, bgp_init_prefix);
-}
-
-void
 bgp_get_route_info(rte *e, byte *buf, ea_list *attrs)
 {
   eattr *p = ea_find(attrs, EA_CODE(EAP_BGP, BA_AS_PATH));
@@ -1953,14 +1896,14 @@ bgp_get_route_info(rte *e, byte *buf, ea_list *attrs)
     buf += bsprintf(buf, "-");
 
   if (e->attrs->hostentry)
-    {
-      if (!rte_resolvable(e))
-	buf += bsprintf(buf, "/-");
-      else if (e->attrs->igp_metric >= IGP_METRIC_UNKNOWN)
-	buf += bsprintf(buf, "/?");
-      else
-	buf += bsprintf(buf, "/%d", e->attrs->igp_metric);
-    }
+  {
+    if (!rte_resolvable(e))
+      buf += bsprintf(buf, "/-");
+    else if (e->attrs->igp_metric >= IGP_METRIC_UNKNOWN)
+      buf += bsprintf(buf, "/?");
+    else
+      buf += bsprintf(buf, "/%d", e->attrs->igp_metric);
+  }
   buf += bsprintf(buf, ") [");
 
   if (p && as_path_get_last(p->u.ptr, &origas))
diff --git a/proto/bgp/bgp.c b/proto/bgp/bgp.c
index cac5d4c4..2ca153ab 100644
--- a/proto/bgp/bgp.c
+++ b/proto/bgp/bgp.c
@@ -2,6 +2,8 @@
  *	BIRD -- The Border Gateway Protocol
  *
  *	(c) 2000 Martin Mares <mj@ucw.cz>
+ *	(c) 2008--2016 Ondrej Zajicek <santiago@crfreenet.org>
+ *	(c) 2008--2016 CZ.NIC z.s.p.o.
  *
  *	Can be freely distributed and used under the terms of the GNU GPL.
  */
@@ -9,48 +11,52 @@
 /**
  * DOC: Border Gateway Protocol
  *
- * The BGP protocol is implemented in three parts: |bgp.c| which takes care of the
- * connection and most of the interface with BIRD core, |packets.c| handling
+ * The BGP protocol is implemented in three parts: |bgp.c| which takes care of
+ * the connection and most of the interface with BIRD core, |packets.c| handling
  * both incoming and outgoing BGP packets and |attrs.c| containing functions for
  * manipulation with BGP attribute lists.
  *
- * As opposed to the other existing routing daemons, BIRD has a sophisticated core
- * architecture which is able to keep all the information needed by BGP in the
- * primary routing table, therefore no complex data structures like a central
- * BGP table are needed. This increases memory footprint of a BGP router with
- * many connections, but not too much and, which is more important, it makes
- * BGP much easier to implement.
+ * As opposed to the other existing routing daemons, BIRD has a sophisticated
+ * core architecture which is able to keep all the information needed by BGP in
+ * the primary routing table, therefore no complex data structures like a
+ * central BGP table are needed. This increases memory footprint of a BGP router
+ * with many connections, but not too much and, which is more important, it
+ * makes BGP much easier to implement.
  *
- * Each instance of BGP (corresponding to a single BGP peer) is described by a &bgp_proto
- * structure to which are attached individual connections represented by &bgp_connection
- * (usually, there exists only one connection, but during BGP session setup, there
- * can be more of them). The connections are handled according to the BGP state machine
- * defined in the RFC with all the timers and all the parameters configurable.
+ * Each instance of BGP (corresponding to a single BGP peer) is described by a
+ * &bgp_proto structure to which are attached individual connections represented
+ * by &bgp_connection (usually, there exists only one connection, but during BGP
+ * session setup, there can be more of them). The connections are handled
+ * according to the BGP state machine defined in the RFC with all the timers and
+ * all the parameters configurable.
  *
- * In incoming direction, we listen on the connection's socket and each time we receive
- * some input, we pass it to bgp_rx(). It decodes packet headers and the markers and
- * passes complete packets to bgp_rx_packet() which distributes the packet according
- * to its type.
+ * In incoming direction, we listen on the connection's socket and each time we
+ * receive some input, we pass it to bgp_rx(). It decodes packet headers and the
+ * markers and passes complete packets to bgp_rx_packet() which distributes the
+ * packet according to its type.
  *
- * In outgoing direction, we gather all the routing updates and sort them to buckets
- * (&bgp_bucket) according to their attributes (we keep a hash table for fast comparison
- * of &rta's and a &fib which helps us to find if we already have another route for
- * the same destination queued for sending, so that we can replace it with the new one
- * immediately instead of sending both updates). There also exists a special bucket holding
- * all the route withdrawals which cannot be queued anywhere else as they don't have any
- * attributes. If we have any packet to send (due to either new routes or the connection
- * tracking code wanting to send a Open, Keepalive or Notification message), we call
- * bgp_schedule_packet() which sets the corresponding bit in a @packet_to_send
- * bit field in &bgp_conn and as soon as the transmit socket buffer becomes empty,
- * we call bgp_fire_tx(). It inspects state of all the packet type bits and calls
- * the corresponding bgp_create_xx() functions, eventually rescheduling the same packet
- * type if we have more data of the same type to send.
+ * In outgoing direction, we gather all the routing updates and sort them to
+ * buckets (&bgp_bucket) according to their attributes (we keep a hash table for
+ * fast comparison of &rta's and a &fib which helps us to find if we already
+ * have another route for the same destination queued for sending, so that we
+ * can replace it with the new one immediately instead of sending both
+ * updates). There also exists a special bucket holding all the route
+ * withdrawals which cannot be queued anywhere else as they don't have any
+ * attributes. If we have any packet to send (due to either new routes or the
+ * connection tracking code wanting to send a Open, Keepalive or Notification
+ * message), we call bgp_schedule_packet() which sets the corresponding bit in a
+ * @packet_to_send bit field in &bgp_conn and as soon as the transmit socket
+ * buffer becomes empty, we call bgp_fire_tx(). It inspects state of all the
+ * packet type bits and calls the corresponding bgp_create_xx() functions,
+ * eventually rescheduling the same packet type if we have more data of the same
+ * type to send.
  *
- * The processing of attributes consists of two functions: bgp_decode_attrs() for checking
- * of the attribute blocks and translating them to the language of BIRD's extended attributes
- * and bgp_encode_attrs() which does the converse. Both functions are built around a
- * @bgp_attr_table array describing all important characteristics of all known attributes.
- * Unknown transitive attributes are attached to the route as %EAF_TYPE_OPAQUE byte streams.
+ * The processing of attributes consists of two functions: bgp_decode_attrs()
+ * for checking of the attribute blocks and translating them to the language of
+ * BIRD's extended attributes and bgp_encode_attrs() which does the
+ * converse. Both functions are built around a @bgp_attr_table array describing
+ * all important characteristics of all known attributes.  Unknown transitive
+ * attributes are attached to the route as %EAF_TYPE_OPAQUE byte streams.
  *
  * BGP protocol implements graceful restart in both restarting (local restart)
  * and receiving (neighbor restart) roles. The first is handled mostly by the
@@ -80,70 +86,143 @@
 
 
 struct linpool *bgp_linpool;		/* Global temporary pool */
-static sock *bgp_listen_sk;		/* Global listening socket */
-static int bgp_counter;			/* Number of protocol instances using the listening socket */
+static list bgp_sockets;		/* Global list of listening sockets */
+
 
-static void bgp_close(struct bgp_proto *p, int apply_md5);
 static void bgp_connect(struct bgp_proto *p);
 static void bgp_active(struct bgp_proto *p);
-static sock *bgp_setup_listen_sk(ip_addr addr, unsigned port, u32 flags);
 static void bgp_update_bfd(struct bgp_proto *p, int use_bfd);
 
+static int bgp_incoming_connection(sock *sk, uint dummy UNUSED);
+static void bgp_listen_sock_err(sock *sk UNUSED, int err);
 
 /**
  * bgp_open - open a BGP instance
  * @p: BGP instance
  *
- * This function allocates and configures shared BGP resources.
- * Should be called as the last step during initialization
- * (when lock is acquired and neighbor is ready).
- * When error, state changed to PS_DOWN, -1 is returned and caller
- * should return immediately.
+ * This function allocates and configures shared BGP resources, mainly listening
+ * sockets. Should be called as the last step during initialization (when lock
+ * is acquired and neighbor is ready). When error, caller should change state to
+ * PS_DOWN and return immediately.
  */
 static int
 bgp_open(struct bgp_proto *p)
 {
-  struct config *cfg = p->cf->c.global;
-  int errcode;
+  struct bgp_socket *bs = NULL;
+  struct iface *ifa = p->cf->strict_bind ? p->cf->iface : NULL;
+  ip_addr addr = p->cf->strict_bind ? p->cf->local_ip :
+    (ipa_is_ip4(p->cf->remote_ip) ? IPA_NONE4 : IPA_NONE6);
+  uint port = p->cf->local_port;
+
+  /* FIXME: Add some global init? */
+  if (!bgp_linpool)
+    init_list(&bgp_sockets);
 
-  if (!bgp_listen_sk)
-    bgp_listen_sk = bgp_setup_listen_sk(cfg->listen_bgp_addr, cfg->listen_bgp_port, cfg->listen_bgp_flags);
+  /* We assume that cf->iface is defined iff cf->local_ip is link-local */
 
-  if (!bgp_listen_sk)
+  WALK_LIST(bs, bgp_sockets)
+    if (ipa_equal(bs->sk->saddr, addr) && (bs->sk->iface == ifa) && (bs->sk->sport == port))
     {
-      errcode = BEM_NO_SOCKET;
-      goto err;
+      bs->uc++;
+      p->sock = bs;
+      return 0;
     }
 
-  if (!bgp_linpool)
-    bgp_linpool = lp_new(&root_pool, 4080);
+  sock *sk = sk_new(proto_pool);
+  sk->type = SK_TCP_PASSIVE;
+  sk->ttl = 255;
+  sk->saddr = addr;
+  sk->sport = port;
+  sk->flags = 0;
+  sk->tos = IP_PREC_INTERNET_CONTROL;
+  sk->rbsize = BGP_RX_BUFFER_SIZE;
+  sk->tbsize = BGP_TX_BUFFER_SIZE;
+  sk->rx_hook = bgp_incoming_connection;
+  sk->err_hook = bgp_listen_sock_err;
+
+  if (sk_open(sk) < 0)
+    goto err;
 
-  bgp_counter++;
+  bs = mb_allocz(proto_pool, sizeof(struct bgp_socket));
+  bs->sk = sk;
+  bs->uc = 1;
+  p->sock = bs;
 
-  if (p->cf->password)
-    if (sk_set_md5_auth(bgp_listen_sk, p->cf->source_addr, p->cf->remote_ip,
-			p->cf->iface, p->cf->password, p->cf->setkey) < 0)
-      {
-	sk_log_error(bgp_listen_sk, p->p.name);
-	bgp_close(p, 0);
-	errcode = BEM_INVALID_MD5;
-	goto err;
-      }
+  add_tail(&bgp_sockets, &bs->n);
+
+  if (!bgp_linpool)
+    bgp_linpool = lp_new(proto_pool, 4080);
 
   return 0;
 
 err:
-  p->p.disabled = 1;
-  bgp_store_error(p, NULL, BE_MISC, errcode);
-  proto_notify_state(&p->p, PS_DOWN);
+  sk_log_error(sk, p->p.name);
+  log(L_ERR "%s: Cannot open listening socket", p->p.name);
+  rfree(sk);
   return -1;
 }
 
+/**
+ * bgp_close - close a BGP instance
+ * @p: BGP instance
+ *
+ * This function frees and deconfigures shared BGP resources.
+ */
+static void
+bgp_close(struct bgp_proto *p)
+{
+  struct bgp_socket *bs = p->sock;
+
+  ASSERT(bs && bs->uc);
+
+  if (--bs->uc)
+    return;
+
+  rfree(bs->sk);
+  rem_node(&bs->n);
+  mb_free(bs);
+
+  if (!EMPTY_LIST(bgp_sockets))
+    return;
+
+  rfree(bgp_linpool);
+  bgp_linpool = NULL;
+}
+
+static inline int
+bgp_setup_auth(struct bgp_proto *p, int enable)
+{
+  if (p->cf->password)
+  {
+    int rv = sk_set_md5_auth(p->sock->sk,
+			     p->cf->local_ip, p->cf->remote_ip, p->cf->iface,
+			     enable ? p->cf->password : NULL, p->cf->setkey);
+
+    if (rv < 0)
+      sk_log_error(p->sock->sk, p->p.name);
+
+    return rv;
+  }
+  else
+    return 0;
+}
+
+static inline struct bgp_channel *
+bgp_find_channel(struct bgp_proto *p, u32 afi)
+{
+  struct bgp_channel *c;
+  WALK_LIST(c, p->p.channels)
+    if (c->afi == afi)
+      return c;
+
+  return NULL;
+}
+
 static void
 bgp_startup(struct bgp_proto *p)
 {
   BGP_TRACE(D_EVENTS, "Started");
-  p->start_state = p->cf->capabilities ? BSS_CONNECT : BSS_CONNECT_NOCAP;
+  p->start_state = BSS_CONNECT;
 
   if (!p->cf->passive)
     bgp_active(p);
@@ -159,50 +238,36 @@ bgp_startup_timeout(timer *t)
 static void
 bgp_initiate(struct bgp_proto *p)
 {
-  int rv = bgp_open(p);
-  if (rv < 0)
-    return;
+  int err_val;
+
+  if (bgp_open(p) < 0)
+  { err_val = BEM_NO_SOCKET; goto err1; }
+
+  if (bgp_setup_auth(p, 1) < 0)
+  { err_val = BEM_INVALID_MD5; goto err2; }
 
   if (p->cf->bfd)
     bgp_update_bfd(p, p->cf->bfd);
 
   if (p->startup_delay)
-    {
-      p->start_state = BSS_DELAY;
-      BGP_TRACE(D_EVENTS, "Startup delayed by %d seconds due to errors", p->startup_delay);
-      bgp_start_timer(p->startup_timer, p->startup_delay);
-    }
+  {
+    p->start_state = BSS_DELAY;
+    BGP_TRACE(D_EVENTS, "Startup delayed by %d seconds due to errors", p->startup_delay);
+    bgp_start_timer(p->startup_timer, p->startup_delay);
+  }
   else
     bgp_startup(p);
-}
 
-/**
- * bgp_close - close a BGP instance
- * @p: BGP instance
- * @apply_md5: 0 to disable unsetting MD5 auth
- *
- * This function frees and deconfigures shared BGP resources.
- * @apply_md5 is set to 0 when bgp_close is called as a cleanup
- * from failed bgp_open().
- */
-static void
-bgp_close(struct bgp_proto *p, int apply_md5)
-{
-  ASSERT(bgp_counter);
-  bgp_counter--;
+  return;
 
-  if (p->cf->password && apply_md5)
-    if (sk_set_md5_auth(bgp_listen_sk, p->cf->source_addr, p->cf->remote_ip,
-			p->cf->iface, NULL, p->cf->setkey) < 0)
-      sk_log_error(bgp_listen_sk, p->p.name);
+err2:
+  bgp_close(p);
+err1:
+  p->p.disabled = 1;
+  bgp_store_error(p, NULL, BE_MISC, err_val);
+  proto_notify_state(&p->p, PS_DOWN);
 
-  if (!bgp_counter)
-    {
-      rfree(bgp_listen_sk);
-      bgp_listen_sk = NULL;
-      rfree(bgp_linpool);
-      bgp_linpool = NULL;
-    }
+  return;
 }
 
 /**
@@ -210,19 +275,19 @@ bgp_close(struct bgp_proto *p, int apply_md5)
  * @t: timer
  * @value: time to fire (0 to disable the timer)
  *
- * This functions calls tm_start() on @t with time @value and the
- * amount of randomization suggested by the BGP standard. Please use
- * it for all BGP timers.
+ * This functions calls tm_start() on @t with time @value and the amount of
+ * randomization suggested by the BGP standard. Please use it for all BGP
+ * timers.
  */
 void
 bgp_start_timer(timer *t, int value)
 {
   if (value)
-    {
-      /* The randomization procedure is specified in RFC 1771: 9.2.3.3 */
-      t->randomize = value / 4;
-      tm_start(t, value - t->randomize);
-    }
+  {
+    /* The randomization procedure is specified in RFC 1771: 9.2.3.3 */
+    t->randomize = value / 4;
+    tm_start(t, value - t->randomize);
+  }
   else
     tm_stop(t);
 }
@@ -231,8 +296,8 @@ bgp_start_timer(timer *t, int value)
  * bgp_close_conn - close a BGP connection
  * @conn: connection to close
  *
- * This function takes a connection described by the &bgp_conn structure,
- * closes its socket and frees all resources associated with it.
+ * This function takes a connection described by the &bgp_conn structure, closes
+ * its socket and frees all resources associated with it.
  */
 void
 bgp_close_conn(struct bgp_conn *conn)
@@ -241,16 +306,22 @@ bgp_close_conn(struct bgp_conn *conn)
 
   DBG("BGP: Closing connection\n");
   conn->packets_to_send = 0;
-  rfree(conn->connect_retry_timer);
-  conn->connect_retry_timer = NULL;
+  conn->channels_to_send = 0;
+  rfree(conn->connect_timer);
+  conn->connect_timer = NULL;
   rfree(conn->keepalive_timer);
   conn->keepalive_timer = NULL;
   rfree(conn->hold_timer);
   conn->hold_timer = NULL;
-  rfree(conn->sk);
-  conn->sk = NULL;
   rfree(conn->tx_ev);
   conn->tx_ev = NULL;
+  rfree(conn->sk);
+  conn->sk = NULL;
+
+  mb_free(conn->local_caps);
+  conn->local_caps = NULL;
+  mb_free(conn->remote_caps);
+  conn->remote_caps = NULL;
 }
 
 
@@ -258,9 +329,9 @@ bgp_close_conn(struct bgp_conn *conn)
  * bgp_update_startup_delay - update a startup delay
  * @p: BGP instance
  *
- * This function updates a startup delay that is used to postpone next BGP connect.
- * It also handles disable_after_error and might stop BGP instance when error
- * happened and disable_after_error is on.
+ * This function updates a startup delay that is used to postpone next BGP
+ * connect. It also handles disable_after_error and might stop BGP instance
+ * when error happened and disable_after_error is on.
  *
  * It should be called when BGP protocol error happened.
  */
@@ -277,11 +348,11 @@ bgp_update_startup_delay(struct bgp_proto *p)
   p->last_proto_error = now;
 
   if (cf->disable_after_error)
-    {
-      p->startup_delay = 0;
-      p->p.disabled = 1;
-      return;
-    }
+  {
+    p->startup_delay = 0;
+    p->p.disabled = 1;
+    return;
+  }
 
   if (!p->startup_delay)
     p->startup_delay = cf->error_delay_time_min;
@@ -290,32 +361,38 @@ bgp_update_startup_delay(struct bgp_proto *p)
 }
 
 static void
-bgp_graceful_close_conn(struct bgp_conn *conn, unsigned subcode)
+bgp_graceful_close_conn(struct bgp_conn *conn, uint subcode)
 {
   switch (conn->state)
-    {
-    case BS_IDLE:
-    case BS_CLOSE:
-      return;
-    case BS_CONNECT:
-    case BS_ACTIVE:
-      bgp_conn_enter_idle_state(conn);
-      return;
-    case BS_OPENSENT:
-    case BS_OPENCONFIRM:
-    case BS_ESTABLISHED:
-      bgp_error(conn, 6, subcode, NULL, 0);
-      return;
-    default:
-      bug("bgp_graceful_close_conn: Unknown state %d", conn->state);
-    }
+  {
+  case BS_IDLE:
+  case BS_CLOSE:
+    return;
+
+  case BS_CONNECT:
+  case BS_ACTIVE:
+    bgp_conn_enter_idle_state(conn);
+    return;
+
+  case BS_OPENSENT:
+  case BS_OPENCONFIRM:
+  case BS_ESTABLISHED:
+    bgp_error(conn, 6, subcode, NULL, 0);
+    return;
+
+  default:
+    bug("bgp_graceful_close_conn: Unknown state %d", conn->state);
+  }
 }
 
 static void
 bgp_down(struct bgp_proto *p)
 {
   if (p->start_state > BSS_PREPARE)
-    bgp_close(p, 1);
+  {
+    bgp_setup_auth(p, 0);
+    bgp_close(p);
+  }
 
   BGP_TRACE(D_EVENTS, "Down");
   proto_notify_state(&p->p, PS_DOWN);
@@ -327,20 +404,20 @@ bgp_decision(void *vp)
   struct bgp_proto *p = vp;
 
   DBG("BGP: Decision start\n");
-  if ((p->p.proto_state == PS_START)
-      && (p->outgoing_conn.state == BS_IDLE)
-      && (p->incoming_conn.state != BS_OPENCONFIRM)
-      && (!p->cf->passive))
+  if ((p->p.proto_state == PS_START) &&
+      (p->outgoing_conn.state == BS_IDLE) &&
+      (p->incoming_conn.state != BS_OPENCONFIRM) &&
+      !p->cf->passive)
     bgp_active(p);
 
-  if ((p->p.proto_state == PS_STOP)
-      && (p->outgoing_conn.state == BS_IDLE)
-      && (p->incoming_conn.state == BS_IDLE))
+  if ((p->p.proto_state == PS_STOP) &&
+      (p->outgoing_conn.state == BS_IDLE) &&
+      (p->incoming_conn.state == BS_IDLE))
     bgp_down(p);
 }
 
 void
-bgp_stop(struct bgp_proto *p, unsigned subcode)
+bgp_stop(struct bgp_proto *p, uint subcode)
 {
   proto_notify_state(&p->p, PS_STOP);
   bgp_graceful_close_conn(&p->outgoing_conn, subcode);
@@ -349,7 +426,7 @@ bgp_stop(struct bgp_proto *p, unsigned subcode)
 }
 
 static inline void
-bgp_conn_set_state(struct bgp_conn *conn, unsigned new_state)
+bgp_conn_set_state(struct bgp_conn *conn, uint new_state)
 {
   if (conn->bgp->p.mrtdump & MD_STATES)
     mrt_dump_bgp_state_change(conn, conn->state, new_state);
@@ -364,13 +441,17 @@ bgp_conn_enter_openconfirm_state(struct bgp_conn *conn)
   bgp_conn_set_state(conn, BS_OPENCONFIRM);
 }
 
+static const struct bgp_af_caps dummy_af_caps = { };
+
 void
 bgp_conn_enter_established_state(struct bgp_conn *conn)
 {
   struct bgp_proto *p = conn->bgp;
+  struct bgp_caps *local = conn->local_caps;
+  struct bgp_caps *peer = conn->remote_caps;
+  struct bgp_channel *c;
 
   BGP_TRACE(D_EVENTS, "BGP session established");
-  DBG("BGP: UP!!!\n");
 
   /* For multi-hop BGP sessions */
   if (ipa_zero(p->source_addr))
@@ -381,30 +462,87 @@ bgp_conn_enter_established_state(struct bgp_conn *conn)
   p->conn = conn;
   p->last_error_class = 0;
   p->last_error_code = 0;
-  p->feed_state = BFS_NONE;
-  p->load_state = BFS_NONE;
-  bgp_init_bucket_table(p);
-  bgp_init_prefix_table(p, 8);
 
-  int peer_gr_ready = conn->peer_gr_aware && !(conn->peer_gr_flags & BGP_GRF_RESTART);
+  p->as4_session = conn->as4_session;
+
+  p->route_refresh = peer->route_refresh;
+  p->enhanced_refresh = local->enhanced_refresh && peer->enhanced_refresh;
 
-  if (p->p.gr_recovery && !peer_gr_ready)
-    proto_graceful_restart_unlock(&p->p);
+  /* Whether we may handle possible GR of peer (it has some AF GR-able) */
+  p->gr_ready = 0;	/* Updated later */
 
-  if (p->p.gr_recovery && (p->cf->gr_mode == BGP_GR_ABLE) && peer_gr_ready)
-    p->p.gr_wait = 1;
+  /* Whether peer is ready to handle our GR recovery */
+  int peer_gr_ready = peer->gr_aware && !(peer->gr_flags & BGP_GRF_RESTART);
 
-  if (p->gr_active)
+  if (p->gr_active_num)
     tm_stop(p->gr_timer);
 
-  if (p->gr_active && (!conn->peer_gr_able || !(conn->peer_gr_aflags & BGP_GRF_FORWARDING)))
-    bgp_graceful_restart_done(p);
+  /* Number of active channels */
+  int num = 0;
+
+  WALK_LIST(c, p->p.channels)
+  {
+    const struct bgp_af_caps *loc = bgp_find_af_caps(local, c->afi);
+    const struct bgp_af_caps *rem = bgp_find_af_caps(peer,  c->afi);
+
+    /* Ignore AFIs that were not announced in multiprotocol capability */
+    if (!loc || !loc->ready)
+      loc = &dummy_af_caps;
+
+    if (!rem || !rem->ready)
+      rem = &dummy_af_caps;
+
+    int active = loc->ready && rem->ready;
+    c->c.disabled = !active;
+    c->c.reloadable = p->route_refresh;
+
+    c->index = active ? num++ : 0;
+
+    c->feed_state = BFS_NONE;
+    c->load_state = BFS_NONE;
+
+    /* Channels where peer may do GR */
+    c->gr_ready = active && local->gr_aware && rem->gr_able;
+    p->gr_ready = p->gr_ready || c->gr_ready;
 
-  /* GR capability implies that neighbor will send End-of-RIB */
-  if (conn->peer_gr_aware)
-    p->load_state = BFS_LOADING;
+    /* Channels not able to recover gracefully */
+    if (p->p.gr_recovery && (!active || !peer_gr_ready))
+      channel_graceful_restart_unlock(&c->c);
 
-  /* proto_notify_state() will likely call bgp_feed_begin(), setting p->feed_state */
+    /* Channels waiting for local convergence */
+    if (p->p.gr_recovery && loc->gr_able && peer_gr_ready)
+      c->c.gr_wait = 1;
+
+    /* Channels where peer is not able to recover gracefully */
+    if (c->gr_active && ! (c->gr_ready && (rem->gr_af_flags & BGP_GRF_FORWARDING)))
+      bgp_graceful_restart_done(c);
+
+    /* GR capability implies that neighbor will send End-of-RIB */
+    if (peer->gr_aware)
+      c->load_state = BFS_LOADING;
+
+    c->add_path_rx = (loc->add_path & BGP_ADD_PATH_RX) && (rem->add_path & BGP_ADD_PATH_TX);
+    c->add_path_tx = (loc->add_path & BGP_ADD_PATH_TX) && (rem->add_path & BGP_ADD_PATH_RX);
+
+    // XXXX reset back to non-ANY?
+    if (c->add_path_tx)
+      c->c.ra_mode = RA_ANY;
+  }
+
+  p->afi_map = mb_alloc(p->p.pool, num * sizeof(u32));
+  p->channel_map = mb_alloc(p->p.pool, num * sizeof(void *));
+  p->channel_count = num;
+
+  WALK_LIST(c, p->p.channels)
+  {
+    if (c->c.disabled)
+      continue;
+
+    p->afi_map[c->index] = c->afi;
+    p->channel_map[c->index] = c;
+  }
+
+  /* proto_notify_state() will likely call bgp_feed_begin(), setting c->feed_state */
 
   bgp_conn_set_state(conn, BS_ESTABLISHED);
   proto_notify_state(&p->p, PS_UP);
@@ -468,34 +606,57 @@ bgp_handle_graceful_restart(struct bgp_proto *p)
   ASSERT(p->conn && (p->conn->state == BS_ESTABLISHED) && p->gr_ready);
 
   BGP_TRACE(D_EVENTS, "Neighbor graceful restart detected%s",
-	    p->gr_active ? " - already pending" : "");
-  proto_notify_state(&p->p, PS_START);
+	    p->gr_active_num ? " - already pending" : "");
+
+  p->gr_active_num = 0;
 
-  if (p->gr_active)
-    rt_refresh_end(p->p.main_ahook->table, p->p.main_ahook);
+  struct bgp_channel *c;
+  WALK_LIST(c, p->p.channels)
+  {
+    if (c->gr_ready)
+    {
+      if (c->gr_active)
+	rt_refresh_end(c->c.table, &c->c);
 
-  p->gr_active = 1;
-  bgp_start_timer(p->gr_timer, p->conn->peer_gr_time);
-  rt_refresh_begin(p->p.main_ahook->table, p->p.main_ahook);
+      c->gr_active = 1;
+      p->gr_active_num++;
+      rt_refresh_begin(c->c.table, &c->c);
+    }
+    else
+    {
+      /* Just flush the routes */
+      rt_refresh_begin(c->c.table, &c->c);
+      rt_refresh_end(c->c.table, &c->c);
+    }
+  }
+
+  proto_notify_state(&p->p, PS_START);
+  bgp_start_timer(p->gr_timer, p->conn->local_caps->gr_time);
 }
 
 /**
  * bgp_graceful_restart_done - finish active BGP graceful restart
- * @p: BGP instance
+ * @c: BGP channel
  *
  * This function is called when the active BGP graceful restart of the neighbor
- * should be finished - either successfully (the neighbor sends all paths and
- * reports end-of-RIB on the new session) or unsuccessfully (the neighbor does
- * not support BGP graceful restart on the new session). The function ends
- * routing table refresh cycle and stops BGP restart timer.
+ * should be finished for channel @c - either successfully (the neighbor sends
+ * all paths and reports end-of-RIB for given AFI/SAFI on the new session) or
+ * unsuccessfully (the neighbor does not support BGP graceful restart on the new
+ * session). The function ends the routing table refresh cycle.
  */
 void
-bgp_graceful_restart_done(struct bgp_proto *p)
+bgp_graceful_restart_done(struct bgp_channel *c)
 {
-  BGP_TRACE(D_EVENTS, "Neighbor graceful restart done");
-  p->gr_active = 0;
-  tm_stop(p->gr_timer);
-  rt_refresh_end(p->p.main_ahook->table, p->p.main_ahook);
+  struct bgp_proto *p = (void *) c->c.proto;
+
+  ASSERT(c->gr_active);
+  c->gr_active = 0;
+  p->gr_active_num--;
+
+  if (!p->gr_active_num)
+    BGP_TRACE(D_EVENTS, "Neighbor graceful restart done");
+
+  rt_refresh_end(c->c.table, &c->c);
 }
 
 /**
@@ -519,7 +680,7 @@ bgp_graceful_restart_timeout(timer *t)
 
 /**
  * bgp_refresh_begin - start incoming enhanced route refresh sequence
- * @p: BGP instance
+ * @c: BGP channel
  *
  * This function is called when an incoming enhanced route refresh sequence is
  * started by the neighbor, demarcated by the BoRR packet. The function updates
@@ -528,18 +689,20 @@ bgp_graceful_restart_timeout(timer *t)
  * ensure that these two sequences do not overlap.
  */
 void
-bgp_refresh_begin(struct bgp_proto *p)
+bgp_refresh_begin(struct bgp_channel *c)
 {
-  if (p->load_state == BFS_LOADING)
-    { log(L_WARN "%s: BEGIN-OF-RR received before END-OF-RIB, ignoring", p->p.name); return; }
+  struct bgp_proto *p = (void *) c->c.proto;
+
+  if (c->load_state == BFS_LOADING)
+  { log(L_WARN "%s: BEGIN-OF-RR received before END-OF-RIB, ignoring", p->p.name); return; }
 
-  p->load_state = BFS_REFRESHING;
-  rt_refresh_begin(p->p.main_ahook->table, p->p.main_ahook);
+  c->load_state = BFS_REFRESHING;
+  rt_refresh_begin(c->c.table, &c->c);
 }
 
 /**
  * bgp_refresh_end - finish incoming enhanced route refresh sequence
- * @p: BGP instance
+ * @c: BGP channel
  *
  * This function is called when an incoming enhanced route refresh sequence is
  * finished by the neighbor, demarcated by the EoRR packet. The function updates
@@ -547,39 +710,26 @@ bgp_refresh_begin(struct bgp_proto *p)
  * during the sequence are removed by the nest.
  */
 void
-bgp_refresh_end(struct bgp_proto *p)
+bgp_refresh_end(struct bgp_channel *c)
 {
-  if (p->load_state != BFS_REFRESHING)
-    { log(L_WARN "%s: END-OF-RR received without prior BEGIN-OF-RR, ignoring", p->p.name); return; }
+  struct bgp_proto *p = (void *) c->c.proto;
 
-  p->load_state = BFS_NONE;
-  rt_refresh_end(p->p.main_ahook->table, p->p.main_ahook);
+  if (c->load_state != BFS_REFRESHING)
+  { log(L_WARN "%s: END-OF-RR received without prior BEGIN-OF-RR, ignoring", p->p.name); return; }
+
+  c->load_state = BFS_NONE;
+  rt_refresh_end(c->c.table, &c->c);
 }
 
 
 static void
 bgp_send_open(struct bgp_conn *conn)
 {
-  conn->start_state = conn->bgp->start_state;
-
-  // Default values, possibly changed by receiving capabilities.
-  conn->advertised_as = 0;
-  conn->peer_refresh_support = 0;
-  conn->peer_as4_support = 0;
-  conn->peer_add_path = 0;
-  conn->peer_enhanced_refresh_support = 0;
-  conn->peer_gr_aware = 0;
-  conn->peer_gr_able = 0;
-  conn->peer_gr_time = 0;
-  conn->peer_gr_flags = 0;
-  conn->peer_gr_aflags = 0;
-  conn->peer_ext_messages_support = 0;
-
   DBG("BGP: Sending open\n");
   conn->sk->rx_hook = bgp_rx;
   conn->sk->tx_hook = bgp_tx;
-  tm_stop(conn->connect_retry_timer);
-  bgp_schedule_packet(conn, PKT_OPEN);
+  tm_stop(conn->connect_timer);
+  bgp_schedule_packet(conn, NULL, PKT_OPEN);
   bgp_conn_set_state(conn, BS_OPENSENT);
   bgp_start_timer(conn->hold_timer, conn->bgp->cf->initial_hold_time);
 }
@@ -602,10 +752,10 @@ bgp_connect_timeout(timer *t)
 
   DBG("BGP: connect_timeout\n");
   if (p->p.proto_state == PS_START)
-    {
-      bgp_close_conn(conn);
-      bgp_connect(p);
-    }
+  {
+    bgp_close_conn(conn);
+    bgp_connect(p);
+  }
   else
     bgp_conn_enter_idle_state(conn);
 }
@@ -669,7 +819,7 @@ bgp_keepalive_timeout(timer *t)
   struct bgp_conn *conn = t->data;
 
   DBG("BGP: Keepalive timer\n");
-  bgp_schedule_packet(conn, PKT_KEEPALIVE);
+  bgp_schedule_packet(conn, NULL, PKT_KEEPALIVE);
 
   /* Kick TX a bit faster */
   if (ev_active(conn->tx_ev))
@@ -679,21 +829,18 @@ bgp_keepalive_timeout(timer *t)
 static void
 bgp_setup_conn(struct bgp_proto *p, struct bgp_conn *conn)
 {
-  timer *t;
-
   conn->sk = NULL;
   conn->bgp = p;
+
   conn->packets_to_send = 0;
+  conn->channels_to_send = 0;
+  conn->last_channel = 0;
+  conn->last_channel_count = 0;
+
+  conn->connect_timer	= tm_new_set(p->p.pool, bgp_connect_timeout,	conn, 0, 0);
+  conn->hold_timer 	= tm_new_set(p->p.pool, bgp_hold_timeout,	conn, 0, 0);
+  conn->keepalive_timer	= tm_new_set(p->p.pool, bgp_keepalive_timeout,	conn, 0, 0);
 
-  t = conn->connect_retry_timer = tm_new(p->p.pool);
-  t->hook = bgp_connect_timeout;
-  t->data = conn;
-  t = conn->hold_timer = tm_new(p->p.pool);
-  t->hook = bgp_hold_timeout;
-  t->data = conn;
-  t = conn->keepalive_timer = tm_new(p->p.pool);
-  t->hook = bgp_keepalive_timeout;
-  t->data = conn;
   conn->tx_ev = ev_new(p->p.pool);
   conn->tx_ev->hook = bgp_kick_tx;
   conn->tx_ev->data = conn;
@@ -717,7 +864,7 @@ bgp_active(struct bgp_proto *p)
   BGP_TRACE(D_EVENTS, "Connect delayed by %d seconds", delay);
   bgp_setup_conn(p, conn);
   bgp_conn_set_state(conn, BS_ACTIVE);
-  bgp_start_timer(conn->connect_retry_timer, delay);
+  bgp_start_timer(conn->connect_timer, delay);
 }
 
 /**
@@ -731,12 +878,11 @@ bgp_active(struct bgp_proto *p)
 static void
 bgp_connect(struct bgp_proto *p)	/* Enter Connect state and start establishing connection */
 {
-  sock *s;
   struct bgp_conn *conn = &p->outgoing_conn;
   int hops = p->cf->multihop ? : 1;
 
   DBG("BGP: Connecting\n");
-  s = sk_new(p->p.pool);
+  sock *s = sk_new(p->p.pool);
   s->type = SK_TCP_ACTIVE;
   s->saddr = p->source_addr;
   s->daddr = p->cf->remote_ip;
@@ -763,10 +909,10 @@ bgp_connect(struct bgp_proto *p)	/* Enter Connect state and start establishing c
       goto err;
 
   DBG("BGP: Waiting for connect success\n");
-  bgp_start_timer(conn->connect_retry_timer, p->cf->connect_retry_time);
+  bgp_start_timer(conn->connect_timer, p->cf->connect_retry_time);
   return;
 
- err:
+err:
   sk_log_error(s, p->p.name);
   bgp_sock_err(s, 0);
   return;
@@ -780,16 +926,15 @@ bgp_connect(struct bgp_proto *p)	/* Enter Connect state and start establishing c
 static struct bgp_proto *
 bgp_find_proto(sock *sk)
 {
-  struct proto_config *pc;
+  struct bgp_proto *p;
 
-  WALK_LIST(pc, config->protos)
-    if ((pc->protocol == &proto_bgp) && pc->proto)
-      {
-	struct bgp_proto *p = (struct bgp_proto *) pc->proto;
-	if (ipa_equal(p->cf->remote_ip, sk->daddr) &&
-	    (!ipa_is_link_local(sk->daddr) || (p->cf->iface == sk->iface)))
-	  return p;
-      }
+  WALK_LIST(p, proto_list)
+    if ((p->p.proto == &proto_bgp) &&
+	ipa_equal(p->cf->remote_ip, sk->daddr) &&
+	(!ipa_is_link_local(sk->daddr) || (p->cf->iface == sk->iface)) &&
+	(ipa_zero(p->cf->local_ip) || ipa_equal(p->cf->local_ip, sk->saddr)) &&
+	(p->cf->local_port == sk->sport))
+      return p;
 
   return NULL;
 }
@@ -815,12 +960,12 @@ bgp_incoming_connection(sock *sk, uint dummy UNUSED)
   DBG("BGP: Incoming connection from %I port %d\n", sk->daddr, sk->dport);
   p = bgp_find_proto(sk);
   if (!p)
-    {
-      log(L_WARN "BGP: Unexpected connect from unknown address %I%J (port %d)",
-	  sk->daddr, ipa_is_link_local(sk->daddr) ? sk->iface : NULL, sk->dport);
-      rfree(sk);
-      return 0;
-    }
+  {
+    log(L_WARN "BGP: Unexpected connect from unknown address %I%J (port %d)",
+	sk->daddr, ipa_is_link_local(sk->daddr) ? sk->iface : NULL, sk->dport);
+    rfree(sk);
+    return 0;
+  }
 
   /*
    * BIRD should keep multiple incoming connections in OpenSent state (for
@@ -833,26 +978,26 @@ bgp_incoming_connection(sock *sk, uint dummy UNUSED)
     (p->start_state >= BSS_CONNECT) && (!p->incoming_conn.sk);
 
   if (p->conn && (p->conn->state == BS_ESTABLISHED) && p->gr_ready)
-    {
-      bgp_store_error(p, NULL, BE_MISC, BEM_GRACEFUL_RESTART);
-      bgp_handle_graceful_restart(p);
-      bgp_conn_enter_idle_state(p->conn);
-      acc = 1;
-
-      /* There might be separate incoming connection in OpenSent state */
-      if (p->incoming_conn.state > BS_ACTIVE)
-	bgp_close_conn(&p->incoming_conn);
-    }
+  {
+    bgp_store_error(p, NULL, BE_MISC, BEM_GRACEFUL_RESTART);
+    bgp_handle_graceful_restart(p);
+    bgp_conn_enter_idle_state(p->conn);
+    acc = 1;
+
+    /* There might be separate incoming connection in OpenSent state */
+    if (p->incoming_conn.state > BS_ACTIVE)
+      bgp_close_conn(&p->incoming_conn);
+  }
 
   BGP_TRACE(D_EVENTS, "Incoming connection from %I%J (port %d) %s",
 	    sk->daddr, ipa_is_link_local(sk->daddr) ? sk->iface : NULL,
 	    sk->dport, acc ? "accepted" : "rejected");
 
   if (!acc)
-    {
-      rfree(sk);
-      return 0;
-    }
+  {
+    rfree(sk);
+    return 0;
+  }
 
   hops = p->cf->multihop ? : 1;
 
@@ -864,11 +1009,11 @@ bgp_incoming_connection(sock *sk, uint dummy UNUSED)
       goto err;
 
   if (p->cf->enable_extended_messages)
-    {
-      sk->rbsize = BGP_RX_BUFFER_EXT_SIZE;
-      sk->tbsize = BGP_TX_BUFFER_EXT_SIZE;
-      sk_reallocate(sk);
-    }
+  {
+    sk->rbsize = BGP_RX_BUFFER_EXT_SIZE;
+    sk->tbsize = BGP_TX_BUFFER_EXT_SIZE;
+    sk_reallocate(sk);
+  }
 
   bgp_setup_conn(p, &p->incoming_conn);
   bgp_setup_sk(&p->incoming_conn, sk);
@@ -891,34 +1036,6 @@ bgp_listen_sock_err(sock *sk UNUSED, int err)
     log(L_ERR "BGP: Error on listening socket: %M", err);
 }
 
-static sock *
-bgp_setup_listen_sk(ip_addr addr, unsigned port, u32 flags)
-{
-  sock *s = sk_new(&root_pool);
-  DBG("BGP: Creating listening socket\n");
-  s->type = SK_TCP_PASSIVE;
-  s->ttl = 255;
-  s->saddr = addr;
-  s->sport = port ? port : BGP_PORT;
-  s->flags = flags ? 0 : SKF_V6ONLY;
-  s->tos = IP_PREC_INTERNET_CONTROL;
-  s->rbsize = BGP_RX_BUFFER_SIZE;
-  s->tbsize = BGP_TX_BUFFER_SIZE;
-  s->rx_hook = bgp_incoming_connection;
-  s->err_hook = bgp_listen_sock_err;
-
-  if (sk_open(s) < 0)
-    goto err;
-
-  return s;
-
- err:
-  sk_log_error(s, "BGP");
-  log(L_ERR "BGP: Cannot open listening socket");
-  rfree(s);
-  return NULL;
-}
-
 static void
 bgp_start_neighbor(struct bgp_proto *p)
 {
@@ -927,23 +1044,22 @@ bgp_start_neighbor(struct bgp_proto *p)
   if (ipa_zero(p->source_addr))
     p->source_addr = p->neigh->ifa->ip;
 
-#ifdef IPV6
+  if (ipa_is_link_local(p->source_addr))
+    p->link_addr = p->source_addr;
+  else
   {
+    /* Find some link-local address for given iface */
     struct ifa *a;
-    p->local_link = IPA_NONE;
+    p->link_addr = IPA_NONE;
     WALK_LIST(a, p->neigh->iface->addrs)
       if (a->scope == SCOPE_LINK)
-        {
-	  p->local_link = a->ip;
-	  break;
-	}
-
-    if (! ipa_nonzero(p->local_link))
-      log(L_WARN "%s: Missing link local address on interface %s", p->p.name,  p->neigh->iface->name);
+      {
+	p->link_addr = a->ip;
+	break;
+      }
 
-    DBG("BGP: Selected link-level address %I\n", p->local_link);
+    DBG("%s: Selected link-local address %I\n", p->p.name, p->link_addr);
   }
-#endif
 
   bgp_initiate(p);
 }
@@ -963,34 +1079,34 @@ bgp_neigh_notify(neighbor *n)
   int prepare = (ps == PS_START) && (p->start_state == BSS_PREPARE);
 
   if (n->scope <= 0)
+  {
+    if (!prepare)
     {
-      if (!prepare)
-        {
-	  BGP_TRACE(D_EVENTS, "Neighbor lost");
-	  bgp_store_error(p, NULL, BE_MISC, BEM_NEIGHBOR_LOST);
-	  /* Perhaps also run bgp_update_startup_delay(p)? */
-	  bgp_stop(p, 0);
-	}
+      BGP_TRACE(D_EVENTS, "Neighbor lost");
+      bgp_store_error(p, NULL, BE_MISC, BEM_NEIGHBOR_LOST);
+      /* Perhaps also run bgp_update_startup_delay(p)? */
+      bgp_stop(p, 0);
     }
+  }
   else if (p->cf->check_link && !(n->iface->flags & IF_LINK_UP))
+  {
+    if (!prepare)
     {
-      if (!prepare)
-        {
-	  BGP_TRACE(D_EVENTS, "Link down");
-	  bgp_store_error(p, NULL, BE_MISC, BEM_LINK_DOWN);
-	  if (ps == PS_UP)
-	    bgp_update_startup_delay(p);
-	  bgp_stop(p, 0);
-	}
+      BGP_TRACE(D_EVENTS, "Link down");
+      bgp_store_error(p, NULL, BE_MISC, BEM_LINK_DOWN);
+      if (ps == PS_UP)
+	bgp_update_startup_delay(p);
+      bgp_stop(p, 0);
     }
+  }
   else
+  {
+    if (prepare)
     {
-      if (prepare)
-	{
-	  BGP_TRACE(D_EVENTS, "Neighbor ready");
-	  bgp_start_neighbor(p);
-	}
+      BGP_TRACE(D_EVENTS, "Neighbor ready");
+      bgp_start_neighbor(p);
     }
+  }
 }
 
 static void
@@ -1000,13 +1116,13 @@ bgp_bfd_notify(struct bfd_request *req)
   int ps = p->p.proto_state;
 
   if (req->down && ((ps == PS_START) || (ps == PS_UP)))
-    {
-      BGP_TRACE(D_EVENTS, "BFD session down");
-      bgp_store_error(p, NULL, BE_MISC, BEM_BFD_DOWN);
-      if (ps == PS_UP)
-	bgp_update_startup_delay(p);
-      bgp_stop(p, 0);
-    }
+  {
+    BGP_TRACE(D_EVENTS, "BFD session down");
+    bgp_store_error(p, NULL, BE_MISC, BEM_BFD_DOWN);
+    if (ps == PS_UP)
+      bgp_update_startup_delay(p);
+    bgp_stop(p, 0);
+  }
 }
 
 static void
@@ -1018,71 +1134,72 @@ bgp_update_bfd(struct bgp_proto *p, int use_bfd)
 				     bgp_bfd_notify, p);
 
   if (!use_bfd && p->bfd_req)
-    {
-      rfree(p->bfd_req);
-      p->bfd_req = NULL;
-    }
+  {
+    rfree(p->bfd_req);
+    p->bfd_req = NULL;
+  }
 }
 
-static int
-bgp_reload_routes(struct proto *P)
+static void
+bgp_reload_routes(struct channel *C)
 {
-  struct bgp_proto *p = (struct bgp_proto *) P;
-  if (!p->conn || !p->conn->peer_refresh_support)
-    return 0;
+  struct bgp_proto *p = (void *) C->proto;
+  struct bgp_channel *c = (void *) C;
 
-  bgp_schedule_packet(p->conn, PKT_ROUTE_REFRESH);
-  return 1;
+  ASSERT(p->conn && p->route_refresh);
+
+  bgp_schedule_packet(p->conn, c, PKT_ROUTE_REFRESH);
 }
 
 static void
-bgp_feed_begin(struct proto *P, int initial)
+bgp_feed_begin(struct channel *C, int initial)
 {
-  struct bgp_proto *p = (struct bgp_proto *) P;
+  struct bgp_proto *p = (void *) C->proto;
+  struct bgp_channel *c = (void *) C;
 
   /* This should not happen */
   if (!p->conn)
     return;
 
   if (initial && p->cf->gr_mode)
-    p->feed_state = BFS_LOADING;
+    c->feed_state = BFS_LOADING;
 
   /* It is refeed and both sides support enhanced route refresh */
-  if (!initial && p->cf->enable_refresh &&
-      p->conn->peer_enhanced_refresh_support)
-    {
-      /* BoRR must not be sent before End-of-RIB */
-      if (p->feed_state == BFS_LOADING || p->feed_state == BFS_LOADED)
-	return;
+  if (!initial && p->enhanced_refresh)
+  {
+    /* BoRR must not be sent before End-of-RIB */
+    if (c->feed_state == BFS_LOADING || c->feed_state == BFS_LOADED)
+      return;
 
-      p->feed_state = BFS_REFRESHING;
-      bgp_schedule_packet(p->conn, PKT_BEGIN_REFRESH);
-    }
+    c->feed_state = BFS_REFRESHING;
+    bgp_schedule_packet(p->conn, c, PKT_BEGIN_REFRESH);
+  }
 }
 
 static void
-bgp_feed_end(struct proto *P)
+bgp_feed_end(struct channel *C)
 {
-  struct bgp_proto *p = (struct bgp_proto *) P;
+  struct bgp_proto *p = (void *) C->proto;
+  struct bgp_channel *c = (void *) C;
 
   /* This should not happen */
   if (!p->conn)
     return;
 
   /* Non-demarcated feed ended, nothing to do */
-  if (p->feed_state == BFS_NONE)
+  if (c->feed_state == BFS_NONE)
     return;
 
   /* Schedule End-of-RIB packet */
-  if (p->feed_state == BFS_LOADING)
-    p->feed_state = BFS_LOADED;
+  if (c->feed_state == BFS_LOADING)
+    c->feed_state = BFS_LOADED;
 
   /* Schedule EoRR packet */
-  if (p->feed_state == BFS_REFRESHING)
-    p->feed_state = BFS_REFRESHED;
+  if (c->feed_state == BFS_REFRESHING)
+    c->feed_state = BFS_REFRESHED;
 
   /* Kick TX hook */
-  bgp_schedule_packet(p->conn, PKT_UPDATE);
+  bgp_schedule_packet(p->conn, c, PKT_UPDATE);
 }
 
 
@@ -1093,30 +1210,30 @@ bgp_start_locked(struct object_lock *lock)
   struct bgp_config *cf = p->cf;
 
   if (p->p.proto_state != PS_START)
-    {
-      DBG("BGP: Got lock in different state %d\n", p->p.proto_state);
-      return;
-    }
+  {
+    DBG("BGP: Got lock in different state %d\n", p->p.proto_state);
+    return;
+  }
 
   DBG("BGP: Got lock\n");
 
   if (cf->multihop)
-    {
-      /* Multi-hop sessions do not use neighbor entries */
-      bgp_initiate(p);
-      return;
-    }
+  {
+    /* Multi-hop sessions do not use neighbor entries */
+    bgp_initiate(p);
+    return;
+  }
 
   neighbor *n = neigh_find2(&p->p, &cf->remote_ip, cf->iface, NEF_STICKY);
   if (!n)
-    {
-      log(L_ERR "%s: Invalid remote address %I%J", p->p.name, cf->remote_ip, cf->iface);
-      /* As we do not start yet, we can just disable protocol */
-      p->p.disabled = 1;
-      bgp_store_error(p, NULL, BE_MISC, BEM_INVALID_NEXT_HOP);
-      proto_notify_state(&p->p, PS_DOWN);
-      return;
-    }
+  {
+    log(L_ERR "%s: Invalid remote address %I%J", p->p.name, cf->remote_ip, cf->iface);
+    /* As we do not start yet, we can just disable protocol */
+    p->p.disabled = 1;
+    bgp_store_error(p, NULL, BE_MISC, BEM_INVALID_NEXT_HOP);
+    proto_notify_state(&p->p, PS_DOWN);
+    return;
+  }
 
   p->neigh = n;
 
@@ -1141,9 +1258,7 @@ bgp_start(struct proto *P)
   p->neigh = NULL;
   p->bfd_req = NULL;
   p->gr_ready = 0;
-  p->gr_active = 0;
-
-  rt_lock_table(p->igp_table);
+  p->gr_active_num = 0;
 
   p->event = ev_new(p->p.pool);
   p->event->hook = bgp_decision;
@@ -1162,15 +1277,19 @@ bgp_start(struct proto *P)
     p->rr_cluster_id = p->cf->rr_cluster_id ? p->cf->rr_cluster_id : p->local_id;
 
   p->remote_id = 0;
-  p->source_addr = p->cf->source_addr;
+  p->source_addr = p->cf->local_ip;
 
+  /* XXXX */
   if (p->p.gr_recovery && p->cf->gr_mode)
-    proto_graceful_restart_lock(P);
+  {
+    struct bgp_channel *c;
+    WALK_LIST(c, p->p.channels)
+      channel_graceful_restart_lock(&c->c);
+  }
 
   /*
-   *  Before attempting to create the connection, we need to lock the
-   *  port, so that are sure we're the only instance attempting to talk
-   *  with that neighbor.
+   * Before attempting to create the connection, we need to lock the port,
+   * so that we are the only instance attempting to talk with that neighbor.
    */
 
   lock = p->lock = olock_new(P->pool);
@@ -1191,78 +1310,64 @@ static int
 bgp_shutdown(struct proto *P)
 {
   struct bgp_proto *p = (struct bgp_proto *) P;
-  unsigned subcode = 0;
+  uint subcode = 0;
 
   BGP_TRACE(D_EVENTS, "Shutdown requested");
 
   switch (P->down_code)
-    {
-    case PDC_CF_REMOVE:
-    case PDC_CF_DISABLE:
-      subcode = 3; // Errcode 6, 3 - peer de-configured
-      break;
-
-    case PDC_CF_RESTART:
-      subcode = 6; // Errcode 6, 6 - other configuration change
-      break;
-
-    case PDC_CMD_DISABLE:
-    case PDC_CMD_SHUTDOWN:
-      subcode = 2; // Errcode 6, 2 - administrative shutdown
-      break;
-
-    case PDC_CMD_RESTART:
-      subcode = 4; // Errcode 6, 4 - administrative reset
-      break;
-
-    case PDC_RX_LIMIT_HIT:
-    case PDC_IN_LIMIT_HIT:
-      subcode = 1; // Errcode 6, 1 - max number of prefixes reached
-      /* log message for compatibility */
-      log(L_WARN "%s: Route limit exceeded, shutting down", p->p.name);
-      goto limit;
-
-    case PDC_OUT_LIMIT_HIT:
-      subcode = proto_restart ? 4 : 2; // Administrative reset or shutdown
-
-    limit:
-      bgp_store_error(p, NULL, BE_AUTO_DOWN, BEA_ROUTE_LIMIT_EXCEEDED);
-      if (proto_restart)
-	bgp_update_startup_delay(p);
-      else
-	p->startup_delay = 0;
-      goto done;
-    }
+  {
+  case PDC_CF_REMOVE:
+  case PDC_CF_DISABLE:
+    subcode = 3; // Errcode 6, 3 - peer de-configured
+    break;
+
+  case PDC_CF_RESTART:
+    subcode = 6; // Errcode 6, 6 - other configuration change
+    break;
+
+  case PDC_CMD_DISABLE:
+  case PDC_CMD_SHUTDOWN:
+    subcode = 2; // Errcode 6, 2 - administrative shutdown
+    break;
+
+  case PDC_CMD_RESTART:
+    subcode = 4; // Errcode 6, 4 - administrative reset
+    break;
+
+  case PDC_RX_LIMIT_HIT:
+  case PDC_IN_LIMIT_HIT:
+    subcode = 1; // Errcode 6, 1 - max number of prefixes reached
+    /* log message for compatibility */
+    log(L_WARN "%s: Route limit exceeded, shutting down", p->p.name);
+    goto limit;
+
+  case PDC_OUT_LIMIT_HIT:
+    subcode = proto_restart ? 4 : 2; // Administrative reset or shutdown
+
+  limit:
+    bgp_store_error(p, NULL, BE_AUTO_DOWN, BEA_ROUTE_LIMIT_EXCEEDED);
+    if (proto_restart)
+      bgp_update_startup_delay(p);
+    else
+      p->startup_delay = 0;
+    goto done;
+  }
 
   bgp_store_error(p, NULL, BE_MAN_DOWN, 0);
   p->startup_delay = 0;
 
- done:
+done:
   bgp_stop(p, subcode);
   return p->p.proto_state;
 }
 
-static void
-bgp_cleanup(struct proto *P)
-{
-  struct bgp_proto *p = (struct bgp_proto *) P;
-  rt_unlock_table(p->igp_table);
-}
-
-static rtable *
-get_igp_table(struct bgp_config *cf)
-{
-  return cf->igp_table ? cf->igp_table->table : cf->c.table->table;
-}
-
 static struct proto *
-bgp_init(struct proto_config *C)
+bgp_init(struct proto_config *CF)
 {
-  struct proto *P = proto_new(C, sizeof(struct bgp_proto));
-  struct bgp_config *c = (struct bgp_config *) C;
+  struct proto *P = proto_new(CF);
   struct bgp_proto *p = (struct bgp_proto *) P;
+  struct bgp_config *cf = (struct bgp_config *) CF;
 
-  P->accept_ra_types = c->secondary ? RA_ACCEPTED : RA_OPTIMAL;
   P->rt_notify = bgp_rt_notify;
   P->import_control = bgp_import_control;
   P->neigh_notify = bgp_neigh_notify;
@@ -1271,102 +1376,206 @@ bgp_init(struct proto_config *C)
   P->feed_end = bgp_feed_end;
   P->rte_better = bgp_rte_better;
   P->rte_mergable = bgp_rte_mergable;
-  P->rte_recalculate = c->deterministic_med ? bgp_rte_recalculate : NULL;
-
-  p->cf = c;
-  p->local_as = c->local_as;
-  p->remote_as = c->remote_as;
-  p->is_internal = (c->local_as == c->remote_as);
-  p->rs_client = c->rs_client;
-  p->rr_client = c->rr_client;
-  p->igp_table = get_igp_table(c);
+  P->rte_recalculate = cf->deterministic_med ? bgp_rte_recalculate : NULL;
+
+  p->cf = cf;
+  p->local_as = cf->local_as;
+  p->remote_as = cf->remote_as;
+  p->public_as = cf->local_as;
+  p->is_internal = (cf->local_as == cf->remote_as);
+  p->is_interior = p->is_internal || cf->confederation_member;
+  p->rs_client = cf->rs_client;
+  p->rr_client = cf->rr_client;
+
+  /* Confederation ID is used for truly external peers */
+  if (cf->confederation && !p->is_interior)
+    p->public_as = cf->confederation;
+
+  /* Add all channels */
+  struct bgp_channel_config *cc;
+  WALK_LIST(cc, CF->channels)
+    proto_add_channel(P, &cc->c);
 
   return P;
 }
 
+static inline rtable *
+get_igp_table(struct bgp_channel_config *cf)
+{
+  return cf->igp_table ? cf->igp_table->table : cf->c.table->table;
+}
+
+static void
+bgp_channel_init(struct channel *C, struct channel_config *CF)
+{
+  struct bgp_channel *c = (void *) C;
+  struct bgp_channel_config *cf = (void *) CF;
+
+  C->ra_mode = cf->secondary ? RA_ACCEPTED : RA_OPTIMAL;
+
+  c->cf = cf;
+  c->afi = cf->afi;
+  c->desc = bgp_get_af_desc(c->afi);
+  c->igp_table = get_igp_table(cf);
+}
+
+static int
+bgp_channel_start(struct channel *C)
+{
+  struct bgp_proto *p = (void *) C->proto;
+  struct bgp_channel *c = (void *) C;
+  ip_addr src = p->source_addr;
+
+  rt_lock_table(c->igp_table);
+
+  c->pool = p->p.pool; // XXXX
+  bgp_init_bucket_table(c);
+  bgp_init_prefix_table(c);
+
+  c->next_hop_addr = c->cf->next_hop_addr;
+  c->link_addr = IPA_NONE;
+  c->packets_to_send = 0;
+
+  /* Try to use source address as next hop address */
+  if (ipa_zero(c->next_hop_addr))
+  {
+    if (bgp_channel_is_ipv4(c) && ipa_is_ip4(src))
+      c->next_hop_addr = src;
+
+    if (bgp_channel_is_ipv6(c) && ipa_is_ip6(src) && !ipa_is_link_local(src))
+      c->next_hop_addr = src;
+  }
+
+  /* Set link-local address for IPv6 single-hop BGP */
+  if (bgp_channel_is_ipv6(c) && p->neigh)
+  {
+    c->link_addr = p->link_addr;
+
+    if (ipa_zero(c->link_addr))
+      log(L_WARN "%s: Missing link-local address", p->p.name);
+  }
+
+  /* No next hop address is valid on IPv6 link-local BGP */
+  if (ipa_zero(c->next_hop_addr) && !ipa_is_link_local(src))
+    log(L_WARN "%s: Missing next hop address", p->p.name);
+
+  return 0; /* XXXX: Currently undefined */
+}
+
+static void
+bgp_channel_shutdown(struct channel *C)
+{
+  struct bgp_channel *c = (void *) C;
+
+  /* XXXX: cleanup bucket and prefix tables */
+
+  c->next_hop_addr = IPA_NONE;
+  c->link_addr = IPA_NONE;
+}
+
+static void
+bgp_channel_cleanup(struct channel *C)
+{
+  struct bgp_channel *c = (void *) C;
+
+  rt_unlock_table(c->igp_table);
+}
 
 void
-bgp_check_config(struct bgp_config *c)
+bgp_postconfig(struct proto_config *CF)
 {
-  int internal = (c->local_as == c->remote_as);
+  struct bgp_config *cf = (void *) CF;
+  int internal = (cf->local_as == cf->remote_as);
 
   /* Do not check templates at all */
-  if (c->c.class == SYM_TEMPLATE)
+  if (cf->c.class == SYM_TEMPLATE)
     return;
 
 
   /* EBGP direct by default, IBGP multihop by default */
-  if (c->multihop < 0)
-    c->multihop = internal ? 64 : 0;
-
-  /* Different default for gw_mode */
-  if (!c->gw_mode)
-    c->gw_mode = c->multihop ? GW_RECURSIVE : GW_DIRECT;
-
-  /* Different default based on rs_client */
-  if (!c->missing_lladdr)
-    c->missing_lladdr = c->rs_client ? MLL_IGNORE : MLL_SELF;
+  if (cf->multihop < 0)
+    cf->multihop = internal ? 64 : 0;
 
-  /* Disable after error incompatible with restart limit action */
-  if (c->c.in_limit && (c->c.in_limit->action == PLA_RESTART) && c->disable_after_error)
-    c->c.in_limit->action = PLA_DISABLE;
 
-
-  if (!c->local_as)
+  if (!cf->local_as)
     cf_error("Local AS number must be set");
 
-  if (ipa_zero(c->remote_ip))
+  if (ipa_zero(cf->remote_ip))
     cf_error("Neighbor must be configured");
 
-  if (!c->remote_as)
+  if (!cf->remote_as)
     cf_error("Remote AS number must be set");
 
   // if (ipa_is_link_local(c->remote_ip) && !c->iface)
   //   cf_error("Link-local neighbor address requires specified interface");
 
-  if (!ipa_is_link_local(c->remote_ip) != !c->iface)
+  if (!ipa_is_link_local(cf->remote_ip) != !cf->iface)
     cf_error("Link-local address and interface scope must be used together");
 
-  if (!(c->capabilities && c->enable_as4) && (c->remote_as > 0xFFFF))
+  if (!(cf->capabilities && cf->enable_as4) && (cf->remote_as > 0xFFFF))
     cf_error("Neighbor AS number out of range (AS4 not available)");
 
-  if (!internal && c->rr_client)
+  if (!internal && cf->rr_client)
     cf_error("Only internal neighbor can be RR client");
 
-  if (internal && c->rs_client)
+  if (internal && cf->rs_client)
     cf_error("Only external neighbor can be RS client");
 
-  if (c->multihop && (c->gw_mode == GW_DIRECT))
-    cf_error("Multihop BGP cannot use direct gateway mode");
+  if (!cf->confederation && cf->confederation_member)
+    cf_error("Confederation ID must be set for member sessions");
 
-  if (c->multihop && (ipa_is_link_local(c->remote_ip) ||
-		      ipa_is_link_local(c->source_addr)))
+  if (cf->multihop && (ipa_is_link_local(cf->local_ip) ||
+		       ipa_is_link_local(cf->remote_ip)))
     cf_error("Multihop BGP cannot be used with link-local addresses");
 
-  if (c->multihop && c->check_link)
+  if (cf->multihop && cf->check_link)
     cf_error("Multihop BGP cannot depend on link state");
 
-  if (c->multihop && c->bfd && ipa_zero(c->source_addr))
-    cf_error("Multihop BGP with BFD requires specified source address");
+  if (cf->multihop && cf->bfd && ipa_zero(cf->local_ip))
+    cf_error("Multihop BGP with BFD requires specified local address");
+
+
+  struct bgp_channel_config *cc;
+  WALK_LIST(cc, CF->channels)
+  {
+    /* Disable after error incompatible with restart limit action */
+    if ((cc->c.in_limit.action == PLA_RESTART) && cf->disable_after_error)
+      cc->c.in_limit.action = PLA_DISABLE;
+
+    /* Different default based on rs_client */
+    if (!cc->missing_lladdr)
+      cc->missing_lladdr = cf->rs_client ? MLL_IGNORE : MLL_SELF;
+
+    /* Different default for gw_mode */
+    if (!cc->gw_mode)
+      cc->gw_mode = cf->multihop ? GW_RECURSIVE : GW_DIRECT;
 
-  if ((c->gw_mode == GW_RECURSIVE) && c->c.table->sorted)
-    cf_error("BGP in recursive mode prohibits sorted table");
+    /* Default based on proto config */
+    if (cc->gr_able == 0xff)
+      cc->gr_able = (cf->gr_mode == BGP_GR_ABLE);
 
-  if (c->deterministic_med && c->c.table->sorted)
-    cf_error("BGP with deterministic MED prohibits sorted table");
+    if (cf->multihop && (cc->gw_mode == GW_DIRECT))
+      cf_error("Multihop BGP cannot use direct gateway mode");
 
-  if (c->secondary && !c->c.table->sorted)
-    cf_error("BGP with secondary option requires sorted table");
+    if ((cc->gw_mode == GW_RECURSIVE) && cc->c.table->sorted)
+      cf_error("BGP in recursive mode prohibits sorted table");
+
+    if (cf->deterministic_med && cc->c.table->sorted)
+      cf_error("BGP with deterministic MED prohibits sorted table");
+
+    if (cc->secondary && !cc->c.table->sorted)
+      cf_error("BGP with secondary option requires sorted table");
+  }
 }
 
 static int
-bgp_reconfigure(struct proto *P, struct proto_config *C)
+bgp_reconfigure(struct proto *P, struct proto_config *CF)
 {
-  struct bgp_config *new = (struct bgp_config *) C;
-  struct bgp_proto *p = (struct bgp_proto *) P;
+  struct bgp_proto *p = (void *) P;
+  struct bgp_config *new = (void *) CF;
   struct bgp_config *old = p->cf;
 
-  if (proto_get_router_id(C) != p->local_id)
+  if (proto_get_router_id(CF) != p->local_id)
     return 0;
 
   int same = !memcmp(((byte *) old) + sizeof(struct proto_config),
@@ -1374,8 +1583,26 @@ bgp_reconfigure(struct proto *P, struct proto_config *C)
 		     // password item is last and must be checked separately
 		     OFFSETOF(struct bgp_config, password) - sizeof(struct proto_config))
     && ((!old->password && !new->password)
-	|| (old->password && new->password && !strcmp(old->password, new->password)))
-    && (get_igp_table(old) == get_igp_table(new));
+	|| (old->password && new->password && !strcmp(old->password, new->password)));
+
+  /* FIXME: Move channel reconfiguration to generic protocol code ? */
+  struct channel *C, *C2;
+  struct bgp_channel_config *cc;
+
+  WALK_LIST(C, p->p.channels)
+    C->stale = 1;
+
+  WALK_LIST(cc, new->c.channels)
+  {
+    C = (struct channel *) bgp_find_channel(p, cc->afi);
+    same = proto_configure_channel(P, &C, &cc->c) && same;
+    C->stale = 0;
+  }
+
+  WALK_LIST_DELSAFE(C, C2, p->p.channels)
+    if (C->stale)
+      same = proto_configure_channel(P, &C, NULL) && same;
+
 
   if (same && (p->start_state > BSS_PREPARE))
     bgp_update_bfd(p, new->bfd);
@@ -1387,8 +1614,28 @@ bgp_reconfigure(struct proto *P, struct proto_config *C)
   return same;
 }
 
+static int
+bgp_channel_reconfigure(struct channel *C, struct channel_config *CC)
+{
+  struct bgp_channel *c = (void *) C;
+  struct bgp_channel_config *new = (void *) CC;
+  struct bgp_channel_config *old = c->cf;
+
+  if (memcmp(((byte *) old) + sizeof(struct channel_config),
+	     ((byte *) new) + sizeof(struct channel_config),
+	     /* igp_table item is last and must be checked separately */
+	     OFFSETOF(struct bgp_channel_config, igp_table) - sizeof(struct channel_config)))
+    return 0;
+
+  if (get_igp_table(old) != get_igp_table(new))
+    return 0;
+
+  c->cf = new;
+  return 1;
+}
+
 static void
-bgp_copy_config(struct proto_config *dest, struct proto_config *src)
+bgp_copy_config(struct proto_config *dest UNUSED, struct proto_config *src UNUSED)
 {
   /* Just a shallow copy */
 }
@@ -1407,14 +1654,14 @@ bgp_copy_config(struct proto_config *dest, struct proto_config *src)
  * closes the connection.
  */
 void
-bgp_error(struct bgp_conn *c, unsigned code, unsigned subcode, byte *data, int len)
+bgp_error(struct bgp_conn *c, uint code, uint subcode, byte *data, int len)
 {
   struct bgp_proto *p = c->bgp;
 
   if (c->state == BS_CLOSE)
     return;
 
-  bgp_log_error(p, BE_BGP_TX, "Error", code, subcode, data, (len > 0) ? len : -len);
+  bgp_log_error(p, BE_BGP_TX, "Error", code, subcode, data, ABS(len));
   bgp_store_error(p, c, BE_BGP_TX, (code << 16) | subcode);
   bgp_conn_enter_close_state(c);
 
@@ -1422,13 +1669,13 @@ bgp_error(struct bgp_conn *c, unsigned code, unsigned subcode, byte *data, int l
   c->notify_subcode = subcode;
   c->notify_data = data;
   c->notify_size = (len > 0) ? len : 0;
-  bgp_schedule_packet(c, PKT_NOTIFICATION);
+  bgp_schedule_packet(c, NULL, PKT_NOTIFICATION);
 
   if (code != 6)
-    {
-      bgp_update_startup_delay(p);
-      bgp_stop(p, 0);
-    }
+  {
+    bgp_update_startup_delay(p);
+    bgp_stop(p, 0);
+  }
 }
 
 /**
@@ -1467,19 +1714,19 @@ static const char *
 bgp_last_errmsg(struct bgp_proto *p)
 {
   switch (p->last_error_class)
-    {
-    case BE_MISC:
-      return bgp_misc_errors[p->last_error_code];
-    case BE_SOCKET:
-      return (p->last_error_code == 0) ? "Connection closed" : strerror(p->last_error_code);
-    case BE_BGP_RX:
-    case BE_BGP_TX:
-      return bgp_error_dsc(p->last_error_code >> 16, p->last_error_code & 0xFF);
-    case BE_AUTO_DOWN:
-      return bgp_auto_errors[p->last_error_code];
-    default:
-      return "";
-    }
+  {
+  case BE_MISC:
+    return bgp_misc_errors[p->last_error_code];
+  case BE_SOCKET:
+    return (p->last_error_code == 0) ? "Connection closed" : strerror(p->last_error_code);
+  case BE_BGP_RX:
+  case BE_BGP_TX:
+    return bgp_error_dsc(p->last_error_code >> 16, p->last_error_code & 0xFF);
+  case BE_AUTO_DOWN:
+    return bgp_auto_errors[p->last_error_code];
+  default:
+    return "";
+  }
 }
 
 static const char *
@@ -1515,35 +1762,34 @@ bgp_show_proto_info(struct proto *P)
   struct bgp_proto *p = (struct bgp_proto *) P;
   struct bgp_conn *c = p->conn;
 
-  proto_show_basic_info(P);
-
   cli_msg(-1006, "  BGP state:          %s", bgp_state_dsc(p));
   cli_msg(-1006, "    Neighbor address: %I%J", p->cf->remote_ip, p->cf->iface);
   cli_msg(-1006, "    Neighbor AS:      %u", p->remote_as);
 
-  if (p->gr_active)
+  if (p->gr_active_num)
     cli_msg(-1006, "    Neighbor graceful restart active");
 
   if (P->proto_state == PS_START)
-    {
-      struct bgp_conn *oc = &p->outgoing_conn;
+  {
+    struct bgp_conn *oc = &p->outgoing_conn;
 
-      if ((p->start_state < BSS_CONNECT) &&
-	  (p->startup_timer->expires))
-	cli_msg(-1006, "    Error wait:       %d/%d",
-		p->startup_timer->expires - now, p->startup_delay);
+    if ((p->start_state < BSS_CONNECT) &&
+	(p->startup_timer->expires))
+      cli_msg(-1006, "    Error wait:       %d/%d",
+	      p->startup_timer->expires - now, p->startup_delay);
 
-      if ((oc->state == BS_ACTIVE) &&
-	  (oc->connect_retry_timer->expires))
-	cli_msg(-1006, "    Connect delay:    %d/%d",
-		oc->connect_retry_timer->expires - now, p->cf->connect_delay_time);
+    if ((oc->state == BS_ACTIVE) &&
+	(oc->connect_timer->expires))
+      cli_msg(-1006, "    Connect delay:    %d/%d",
+	      oc->connect_timer->expires - now, p->cf->connect_delay_time);
 
-      if (p->gr_active && p->gr_timer->expires)
-	cli_msg(-1006, "    Restart timer:    %d/-", p->gr_timer->expires - now);
-    }
+    if (p->gr_active_num && p->gr_timer->expires)
+      cli_msg(-1006, "    Restart timer:    %d/-", p->gr_timer->expires - now);
+  }
   else if (P->proto_state == PS_UP)
-    {
-      cli_msg(-1006, "    Neighbor ID:      %R", p->remote_id);
+  {
+    cli_msg(-1006, "    Neighbor ID:      %R", p->remote_id);
+/* XXXX
       cli_msg(-1006, "    Neighbor caps:   %s%s%s%s%s%s%s",
 	      c->peer_refresh_support ? " refresh" : "",
 	      c->peer_enhanced_refresh_support ? " enhanced-refresh" : "",
@@ -1561,35 +1807,52 @@ bgp_show_proto_info(struct proto *P)
 	      p->add_path_rx ? " add-path-rx" : "",
 	      p->add_path_tx ? " add-path-tx" : "",
 	      p->ext_messages ? " ext-messages" : "");
-      cli_msg(-1006, "    Source address:   %I", p->source_addr);
-      if (P->cf->in_limit)
-	cli_msg(-1006, "    Route limit:      %d/%d",
-		p->p.stats.imp_routes + p->p.stats.filt_routes, P->cf->in_limit->limit);
-      cli_msg(-1006, "    Hold timer:       %d/%d",
-	      tm_remains(c->hold_timer), c->hold_time);
-      cli_msg(-1006, "    Keepalive timer:  %d/%d",
-	      tm_remains(c->keepalive_timer), c->keepalive_time);
-    }
+*/
+    cli_msg(-1006, "    Source address:   %I", p->source_addr);
+    cli_msg(-1006, "    Hold timer:       %d/%d",
+	    tm_remains(c->hold_timer), c->hold_time);
+    cli_msg(-1006, "    Keepalive timer:  %d/%d",
+	    tm_remains(c->keepalive_timer), c->keepalive_time);
+  }
 
   if ((p->last_error_class != BE_NONE) &&
       (p->last_error_class != BE_MAN_DOWN))
-    {
-      const char *err1 = bgp_err_classes[p->last_error_class];
-      const char *err2 = bgp_last_errmsg(p);
-      cli_msg(-1006, "    Last error:       %s%s", err1, err2);
-    }
+  {
+    const char *err1 = bgp_err_classes[p->last_error_class];
+    const char *err2 = bgp_last_errmsg(p);
+    cli_msg(-1006, "    Last error:       %s%s", err1, err2);
+  }
+
+  {
+    /* XXXX ?? */
+    struct channel *c;
+    WALK_LIST(c, p->p.channels)
+      channel_show_info(c);
+  }
 }
 
+struct channel_class channel_bgp = {
+  .channel_size =	sizeof(struct bgp_channel),
+  .config_size =	sizeof(struct bgp_channel_config),
+  .init =		bgp_channel_init,
+  .start =		bgp_channel_start,
+  .shutdown =		bgp_channel_shutdown,
+  .cleanup =		bgp_channel_cleanup,
+  .reconfigure =	bgp_channel_reconfigure,
+};
+
 struct protocol proto_bgp = {
   .name = 		"BGP",
   .template = 		"bgp%d",
   .attr_class = 	EAP_BGP,
   .preference = 	DEF_PREF_BGP,
+  .channel_mask =	NB_IP,
+  .proto_size =		sizeof(struct bgp_proto),
   .config_size =	sizeof(struct bgp_config),
+  .postconfig =		bgp_postconfig,
   .init = 		bgp_init,
   .start = 		bgp_start,
   .shutdown = 		bgp_shutdown,
-  .cleanup = 		bgp_cleanup,
   .reconfigure = 	bgp_reconfigure,
   .copy_config = 	bgp_copy_config,
   .get_status = 	bgp_get_status,
diff --git a/proto/bgp/bgp.h b/proto/bgp/bgp.h
index b4067f3a..4ecb86a0 100644
--- a/proto/bgp/bgp.h
+++ b/proto/bgp/bgp.h
@@ -2,6 +2,8 @@
  *	BIRD -- The Border Gateway Protocol
  *
  *	(c) 2000 Martin Mares <mj@ucw.cz>
+ *	(c) 2008--2016 Ondrej Zajicek <santiago@crfreenet.org>
+ *	(c) 2008--2016 CZ.NIC z.s.p.o.
  *
  *	Can be freely distributed and used under the terms of the GNU GPL.
  */
@@ -10,26 +12,66 @@
 #define _BIRD_BGP_H_
 
 #include <stdint.h>
+#include <setjmp.h>
+#include "nest/bird.h"
 #include "nest/route.h"
 #include "nest/bfd.h"
+//#include "lib/lists.h"
 #include "lib/hash.h"
+#include "lib/socket.h"
 
 struct linpool;
 struct eattr;
 
+
+/* Address families */
+
+#define BGP_AFI_IPV4		1
+#define BGP_AFI_IPV6		2
+
+#define BGP_SAFI_UNICAST	1
+#define BGP_SAFI_MULTICAST	2
+
+/* Internal AF codes */
+
+#define BGP_AF(A, B)		(((u32)(A) << 16) | (u32)(B))
+#define BGP_AFI(A)		((u32)(A) >> 16)
+#define BGP_SAFI(A)		((u32)(A) & 0xFFFF)
+
+#define BGP_AF_IPV4		BGP_AF( BGP_AFI_IPV4, BGP_SAFI_UNICAST )
+#define BGP_AF_IPV6		BGP_AF( BGP_AFI_IPV6, BGP_SAFI_UNICAST )
+#define BGP_AF_IPV4_MC		BGP_AF( BGP_AFI_IPV4, BGP_SAFI_MULTICAST )
+#define BGP_AF_IPV6_MC		BGP_AF( BGP_AFI_IPV6, BGP_SAFI_MULTICAST )
+
+
+struct bgp_write_state;
+struct bgp_parse_state;
+struct bgp_export_state;
+struct bgp_bucket;
+
+struct bgp_af_desc {
+  u32 afi;
+  u32 net;
+  const char *name;
+  uint (*encode_nlri)(struct bgp_write_state *s, struct bgp_bucket *buck, byte *buf, uint size);
+  void (*decode_nlri)(struct bgp_parse_state *s, byte *pos, uint len, rta *a);
+  void (*update_next_hop)(struct bgp_export_state *s, eattr *nh, ea_list **to);
+  uint (*encode_next_hop)(struct bgp_write_state *s, eattr *nh, byte *buf, uint size);
+  void (*decode_next_hop)(struct bgp_parse_state *s, byte *pos, uint len, rta *a);
+};
+
+
 struct bgp_config {
   struct proto_config c;
   u32 local_as, remote_as;
+  ip_addr local_ip;			/* Source address to use */
   ip_addr remote_ip;
-  ip_addr source_addr;			/* Source address to use */
   struct iface *iface;			/* Interface for link-local addresses */
+  u16 local_port;			/* Local listening port */
   u16 remote_port; 			/* Neighbor destination port */
   int multihop;				/* Number of hops if multihop */
-  int ttl_security;			/* Enable TTL security [RFC5082] */
-  int next_hop_self;			/* Always set next hop to local IP address */
-  int next_hop_keep;			/* Do not touch next hop attribute */
-  int missing_lladdr;			/* What we will do when we don' know link-local addr, see MLL_* */
-  int gw_mode;				/* How we compute route gateway from next_hop attr, see GW_* */
+  int strict_bind;			/* Bind listening socket to local address XXXX */
+  int ttl_security;			/* Enable TTL security [RFC 5082] */
   int compare_path_lengths;		/* Use path lengths when selecting best route */
   int med_metric;			/* Compare MULTI_EXIT_DISC even between routes from differen ASes */
   int igp_metric;			/* Use IGP metrics when selecting best route */
@@ -37,18 +79,17 @@ struct bgp_config {
   int deterministic_med;		/* Use more complicated algo to have strict RFC 4271 MED comparison */
   u32 default_local_pref;		/* Default value for LOCAL_PREF attribute */
   u32 default_med;			/* Default value for MULTI_EXIT_DISC attribute */
-  int capabilities;			/* Enable capability handshake [RFC3392] */
-  int enable_refresh;			/* Enable local support for route refresh [RFC2918] */
-  int enable_as4;			/* Enable local support for 4B AS numbers [RFC4893] */
+  int capabilities;			/* Enable capability handshake [RFC 3392] */
+  int enable_refresh;			/* Enable local support for route refresh [RFC 2918] */
+  int enable_as4;			/* Enable local support for 4B AS numbers [RFC 4893] */
   int enable_extended_messages;		/* Enable local support for extended messages [draft] */
   u32 rr_cluster_id;			/* Route reflector cluster ID, if different from local ID */
   int rr_client;			/* Whether neighbor is RR client of me */
   int rs_client;			/* Whether neighbor is RS client of me */
-  int advertise_ipv4;			/* Whether we should add IPv4 capability advertisement to OPEN message */
+  u32 confederation;			/* Confederation ID, or zero if confeds not active */
+  int confederation_member;		/* Whether neighbor AS is member of our confederation */
   int passive;				/* Do not initiate outgoing connection */
   int interpret_communities;		/* Hardwired handling of well-known communities */
-  int secondary;			/* Accept also non-best routes (i.e. RA_ACCEPTED) */
-  int add_path;				/* Use ADD-PATH extension [draft] */
   int allow_local_as;			/* Allow that number of local ASNs in incoming AS_PATHs */
   int gr_mode;				/* Graceful restart mode (BGP_GR_*) */
   int setkey;				/* Set MD5 password to system SA/SP database */
@@ -63,11 +104,27 @@ struct bgp_config {
   unsigned disable_after_error;		/* Disable the protocol when error is detected */
 
   char *password;			/* Password used for MD5 authentication */
-  struct rtable_config *igp_table;	/* Table used for recursive next hop lookups */
   int check_link;			/* Use iface link state for liveness detection */
   int bfd;				/* Use BFD for liveness detection */
 };
 
+struct bgp_channel_config {
+  struct channel_config c;
+
+  u32 afi;
+
+  ip_addr next_hop_addr;		/* Local address for NEXT_HOP attribute */
+  u8 next_hop_self;			/* Always set next hop to local IP address */
+  u8 next_hop_keep;			/* Do not touch next hop attribute */
+  u8 missing_lladdr;			/* What we will do when we don' know link-local addr, see MLL_* */
+  u8 gw_mode;				/* How we compute route gateway from next_hop attr, see GW_* */
+  u8 secondary;				/* Accept also non-best routes (i.e. RA_ACCEPTED) */
+  u8 gr_able;				/* Allow full graceful restart for the channel */
+  u8 add_path;				/* Use ADD-PATH extension [RFC 7911] */
+
+  struct rtable_config *igp_table;	/* Table used for recursive next hop lookups */
+};
+
 #define MLL_SELF 1
 #define MLL_DROP 2
 #define MLL_IGNORE 3
@@ -75,112 +132,226 @@ struct bgp_config {
 #define GW_DIRECT 1
 #define GW_RECURSIVE 2
 
-#define ADD_PATH_RX 1
-#define ADD_PATH_TX 2
-#define ADD_PATH_FULL 3
+#define BGP_ADD_PATH_RX		1
+#define BGP_ADD_PATH_TX		2
+#define BGP_ADD_PATH_FULL	3
 
-#define BGP_GR_ABLE 1
-#define BGP_GR_AWARE 2
+#define BGP_GR_ABLE		1
+#define BGP_GR_AWARE		2
 
-/* For peer_gr_flags */
+/* For GR capability common flags */
 #define BGP_GRF_RESTART 0x80
 
-/* For peer_gr_aflags */
+/* For GR capability per-AF flags */
 #define BGP_GRF_FORWARDING 0x80
 
 
+struct bgp_af_caps {
+  u32 afi;
+  u8 ready;				/* Multiprotocol capability, RFC 4760 */
+  u8 gr_able;				/* Graceful restart support, RFC 4724 */
+  u8 gr_af_flags;			/* Graceful restart per-AF flags */
+  u8 add_path;				/* Multiple paths support,   RFC 7911 */
+};
+
+struct bgp_caps {
+  u32 as4_number;			/* Announced ASN */
+
+  u8 as4_support;			/* Four-octet AS capability, RFC 6793 */
+  u8 ext_messages;			/* Extended message length,  RFC draft */
+  u8 route_refresh;			/* Route refresh capability, RFC 2918 */
+  u8 enhanced_refresh;			/* Enhanced route refresh,   RFC 7313 */
+
+  u8 gr_aware;				/* Graceful restart capability, RFC 4724 */
+  u8 gr_flags;				/* Graceful restart flags */
+  u16 gr_time;				/* Graceful restart time in seconds */
+
+  u16 af_count;				/* Number of af_data items */
+
+  struct bgp_af_caps af_data[0];	/* Per-AF capability data */
+};
+
+struct bgp_socket {
+  node n;				/* Node in global bgp_sockets */
+  sock *sk;				/* Real listening socket */
+  u32 uc;				/* Use count */
+};
+
 struct bgp_conn {
   struct bgp_proto *bgp;
   struct birdsock *sk;
-  uint state;				/* State of connection state machine */
-  struct timer *connect_retry_timer;
+  u8 state;				/* State of connection state machine */
+  u8 as4_session;			/* Session uses 4B AS numbers in AS_PATH (both sides support it) */
+  u8 ext_messages;			/* Session uses extended message length */
+
+  struct bgp_caps *local_caps;
+  struct bgp_caps *remote_caps;
+  struct timer *connect_timer;
   struct timer *hold_timer;
   struct timer *keepalive_timer;
   struct event *tx_ev;
-  int packets_to_send;			/* Bitmap of packet types to be sent */
+  u32 packets_to_send;			/* Bitmap of packet types to be sent */
+  u32 channels_to_send;			/* Bitmap of channels with packets to be sent */
+  u8 last_channel;			/* Channel used last time for TX */
+  u8 last_channel_count;		/* Number of times the last channel was used in succession */
   int notify_code, notify_subcode, notify_size;
   byte *notify_data;
-  u32 advertised_as;			/* Temporary value for AS number received */
-  int start_state;			/* protocol start_state snapshot when connection established */
-  u8 peer_refresh_support;		/* Peer supports route refresh [RFC2918] */
-  u8 peer_as4_support;			/* Peer supports 4B AS numbers [RFC4893] */
-  u8 peer_add_path;			/* Peer supports ADD-PATH [draft] */
-  u8 peer_enhanced_refresh_support;	/* Peer supports enhanced refresh [RFC7313] */
-  u8 peer_gr_aware;
-  u8 peer_gr_able;
-  u16 peer_gr_time;
-  u8 peer_gr_flags;
-  u8 peer_gr_aflags;
-  u8 peer_ext_messages_support;		/* Peer supports extended message length [draft] */
-  unsigned hold_time, keepalive_time;	/* Times calculated from my and neighbor's requirements */
+
+  uint hold_time, keepalive_time;	/* Times calculated from my and neighbor's requirements */
 };
 
 struct bgp_proto {
   struct proto p;
   struct bgp_config *cf;		/* Shortcut to BGP configuration */
   u32 local_as, remote_as;
-  int start_state;			/* Substates that partitions BS_START */
-  u8 is_internal;			/* Internal BGP connection (local_as == remote_as) */
-  u8 as4_session;			/* Session uses 4B AS numbers in AS_PATH (both sides support it) */
-  u8 add_path_rx;			/* Session expects receive of ADD-PATH extended NLRI */
-  u8 add_path_tx;			/* Session expects transmit of ADD-PATH extended NLRI */
-  u8 ext_messages;			/* Session allows to use extended messages (both sides support it) */
+  u32 public_as;			/* Externally visible ASN (local_as or confederation id) */
   u32 local_id;				/* BGP identifier of this router */
   u32 remote_id;			/* BGP identifier of the neighbor */
   u32 rr_cluster_id;			/* Route reflector cluster ID */
-  int rr_client;			/* Whether neighbor is RR client of me */
-  int rs_client;			/* Whether neighbor is RS client of me */
+  int start_state;			/* Substates that partitions BS_START */
+  u8 is_internal;			/* Internal BGP session (local_as == remote_as) */
+  u8 is_interior;			/* Internal or intra-confederation BGP session */
+  u8 as4_session;			/* Session uses 4B AS numbers in AS_PATH (both sides support it) */
+  u8 rr_client;				/* Whether neighbor is RR client of me */
+  u8 rs_client;				/* Whether neighbor is RS client of me */
+  u8 route_refresh;			/* Route refresh allowed to send [RFC 2918] */
+  u8 enhanced_refresh;			/* Enhanced refresh is negotiated [RFC 7313] */
   u8 gr_ready;				/* Neighbor could do graceful restart */
-  u8 gr_active;				/* Neighbor is doing graceful restart */
-  u8 feed_state;			/* Feed state (TX) for EoR, RR packets, see BFS_* */
-  u8 load_state;			/* Load state (RX) for EoR, RR packets, see BFS_* */
+  u8 gr_active_num;			/* Neighbor is doing GR, number of active channels */
+  u8 channel_count;			/* Number of active channels */
+  u32 *afi_map;				/* Map channel index -> AFI */
+  struct bgp_channel **channel_map;	/* Map channel index -> channel */
   struct bgp_conn *conn;		/* Connection we have established */
   struct bgp_conn outgoing_conn;	/* Outgoing connection we're working with */
   struct bgp_conn incoming_conn;	/* Incoming connection we have neither accepted nor rejected yet */
   struct object_lock *lock;		/* Lock for neighbor connection */
   struct neighbor *neigh;		/* Neighbor entry corresponding to remote ip, NULL if multihop */
+  struct bgp_socket *sock;		/* Shared listening socket */
   struct bfd_request *bfd_req;		/* BFD request, if BFD is used */
   ip_addr source_addr;			/* Local address used as an advertised next hop */
-  rtable *igp_table;			/* Table used for recursive next hop lookups */
+  ip_addr link_addr;			/* Link-local version of source_addr */
   struct event *event;			/* Event for respawning and shutting process */
   struct timer *startup_timer;		/* Timer used to delay protocol startup due to previous errors (startup_delay) */
   struct timer *gr_timer;		/* Timer waiting for reestablishment after graceful restart */
-  struct bgp_bucket **bucket_hash;	/* Hash table of attribute buckets */
-  uint hash_size, hash_count, hash_limit;
-  HASH(struct bgp_prefix) prefix_hash;	/* Prefixes to be sent */
-  slab *prefix_slab;			/* Slab holding prefix nodes */
-  list bucket_queue;			/* Queue of buckets to send */
-  struct bgp_bucket *withdraw_bucket;	/* Withdrawn routes */
   unsigned startup_delay;		/* Time to delay protocol startup by due to errors */
   bird_clock_t last_proto_error;	/* Time of last error that leads to protocol stop */
   u8 last_error_class; 			/* Error class of last error */
   u32 last_error_code;			/* Error code of last error. BGP protocol errors
 					   are encoded as (bgp_err_code << 16 | bgp_err_subcode) */
-#ifdef IPV6
-  byte *mp_reach_start, *mp_unreach_start; /* Multiprotocol BGP attribute notes */
-  unsigned mp_reach_len, mp_unreach_len;
-  ip_addr local_link;			/* Link-level version of source_addr */
-#endif
+};
+
+struct bgp_channel {
+  struct channel c;
+
+  /* Rest are BGP specific data */
+  struct bgp_channel_config *cf;
+  pool *pool; /* XXXX */
+
+  u32 afi;
+  u32 index;
+  const struct bgp_af_desc *desc;
+
+  HASH(struct bgp_bucket) bucket_hash;	/* Hash table of route buckets */
+  struct bgp_bucket *withdraw_bucket;	/* Withdrawn routes */
+  list bucket_queue;			/* Queue of buckets to send (struct bgp_bucket) */
+
+  HASH(struct bgp_prefix) prefix_hash;	/* Prefixes to be sent */
+  slab *prefix_slab;			/* Slab holding prefix nodes */
+
+  rtable *igp_table;			/* Table used for recursive next hop lookups */
+  ip_addr next_hop_addr;		/* Local address for NEXT_HOP attribute */
+  ip_addr link_addr;			/* Link-local version of next_hop_addr */
+
+  u32 packets_to_send;			/* Bitmap of packet types to be sent */
+
+  u8 gr_ready;				/* Neighbor could do GR on this AF */
+  u8 gr_active;				/* Neighbor is doing GR and keeping fwd state */
+
+  u8 add_path_rx;			/* Session expects receive of ADD-PATH extended NLRI */
+  u8 add_path_tx;			/* Session expects transmit of ADD-PATH extended NLRI */
+
+  u8 feed_state;			/* Feed state (TX) for EoR, RR packets, see BFS_* */
+  u8 load_state;			/* Load state (RX) for EoR, RR packets, see BFS_* */
 };
 
 struct bgp_prefix {
-  struct {
-    ip_addr prefix;
-    int pxlen;
-  } n;
+  node buck_node;			/* Node in per-bucket list */
+  struct bgp_prefix *next;		/* Node in prefix hash table */
+  u32 hash;
   u32 path_id;
-  struct bgp_prefix *next;
-  node bucket_node;			/* Node in per-bucket list */
+  net_addr net[0];
 };
 
 struct bgp_bucket {
   node send_node;			/* Node in send queue */
-  struct bgp_bucket *hash_next, *hash_prev;	/* Node in bucket hash table */
-  unsigned hash;			/* Hash over extended attributes */
-  list prefixes;			/* Prefixes in this buckets */
+  struct bgp_bucket *next;		/* Node in bucket hash table */
+  list prefixes;			/* Prefixes in this bucket (struct bgp_prefix) */
+  u32 hash;				/* Hash over extended attributes */
   ea_list eattrs[0];			/* Per-bucket extended attributes */
 };
 
+struct bgp_export_state {
+  struct bgp_proto *proto;
+  struct bgp_channel *channel;
+  struct linpool *pool;
+
+  struct bgp_proto *src;
+  rte *route;
+
+  u32 attrs_seen[1];
+  uint err_withdraw;
+};
+
+struct bgp_write_state {
+  struct bgp_proto *proto;
+  struct bgp_channel *channel;
+  struct linpool *pool;
+
+  int as4_session;
+  int add_path;
+
+  eattr *mp_next_hop;
+};
+
+struct bgp_parse_state {
+  struct bgp_proto *proto;
+  struct bgp_channel *channel;
+  struct linpool *pool;
+
+  int as4_session;
+  int add_path;
+
+  u32 attrs_seen[256/32];
+
+  u32 mp_reach_af;
+  u32 mp_unreach_af;
+
+  uint attr_len;
+  uint ip_reach_len;
+  uint ip_unreach_len;
+  uint ip_next_hop_len;
+  uint mp_reach_len;
+  uint mp_unreach_len;
+  uint mp_next_hop_len;
+
+  byte *attrs;
+  byte *ip_reach_nlri;
+  byte *ip_unreach_nlri;
+  byte *ip_next_hop_data;
+  byte *mp_reach_nlri;
+  byte *mp_unreach_nlri;
+  byte *mp_next_hop_data;
+
+  uint err_withdraw;
+  uint err_subcode;
+  jmp_buf err_jmpbuf;
+
+  /* Cached state for bgp_rte_update() */
+  u32 last_id;
+  struct rte_src *last_src;
+  rta *cached_rta;
+};
+
 #define BGP_PORT		179
 #define BGP_VERSION		4
 #define BGP_HEADER_LENGTH	19
@@ -191,8 +362,21 @@ struct bgp_bucket {
 #define BGP_RX_BUFFER_EXT_SIZE	65535
 #define BGP_TX_BUFFER_EXT_SIZE	65535
 
-static inline uint bgp_max_packet_length(struct bgp_proto *p)
-{ return p->ext_messages ? BGP_MAX_EXT_MSG_LENGTH : BGP_MAX_MESSAGE_LENGTH; }
+static inline int bgp_channel_is_ipv4(struct bgp_channel *c)
+{ return BGP_AFI(c->afi) == BGP_AFI_IPV4; }
+
+static inline int bgp_channel_is_ipv6(struct bgp_channel *c)
+{ return BGP_AFI(c->afi) == BGP_AFI_IPV6; }
+
+static inline uint bgp_max_packet_length(struct bgp_conn *conn)
+{ return conn->ext_messages ? BGP_MAX_EXT_MSG_LENGTH : BGP_MAX_MESSAGE_LENGTH; }
+
+static inline void
+bgp_parse_error(struct bgp_parse_state *s, uint subcode)
+{
+  s->err_subcode = subcode;
+  longjmp(s->err_jmpbuf, 1);
+}
 
 extern struct linpool *bgp_linpool;
 
@@ -207,9 +391,9 @@ void bgp_conn_enter_established_state(struct bgp_conn *conn);
 void bgp_conn_enter_close_state(struct bgp_conn *conn);
 void bgp_conn_enter_idle_state(struct bgp_conn *conn);
 void bgp_handle_graceful_restart(struct bgp_proto *p);
-void bgp_graceful_restart_done(struct bgp_proto *p);
-void bgp_refresh_begin(struct bgp_proto *p);
-void bgp_refresh_end(struct bgp_proto *p);
+void bgp_graceful_restart_done(struct bgp_channel *c);
+void bgp_refresh_begin(struct bgp_channel *c);
+void bgp_refresh_end(struct bgp_channel *c);
 void bgp_store_error(struct bgp_proto *p, struct bgp_conn *c, u8 class, u32 code);
 void bgp_stop(struct bgp_proto *p, unsigned subcode);
 
@@ -232,46 +416,83 @@ struct rte_source *bgp_get_source(struct bgp_proto *p, u32 path_id);
 
 /* attrs.c */
 
+static inline eattr *
+bgp_find_attr(ea_list *attrs, uint code)
+{
+  return ea_find(attrs, EA_CODE(EAP_BGP, code));
+}
+
+eattr *
+bgp_set_attr(ea_list **attrs, struct linpool *pool, uint code, uint flags, uintptr_t val);
+
+static inline void
+bgp_set_attr_u32(ea_list **to, struct linpool *pool, uint code, uint flags, u32 val)
+{ bgp_set_attr(to, pool, code, flags, (uintptr_t) val); }
+
+static inline void
+bgp_set_attr_ptr(ea_list **to, struct linpool *pool, uint code, uint flags, struct adata *val)
+{ bgp_set_attr(to, pool, code, flags, (uintptr_t) val); }
+
+static inline void
+bgp_set_attr_data(ea_list **to, struct linpool *pool, uint code, uint flags, void *data, uint len)
+{
+  struct adata *a = lp_alloc_adata(pool, len);
+  memcpy(a->data, data, len);
+  bgp_set_attr(to, pool, code, flags, (uintptr_t) a);
+}
+
+static inline void
+bgp_unset_attr(ea_list **to, struct linpool *pool, uint code)
+{ eattr *e = bgp_set_attr(to, pool, code, 0, 0); e->type = EAF_TYPE_UNDEF; }
+
+
+
+
 /* Hack: although BA_NEXT_HOP attribute has type EAF_TYPE_IP_ADDRESS, in IPv6
  * we store two addesses in it - a global address and a link local address.
  */
-#ifdef IPV6
+#ifdef XXX
 #define NEXT_HOP_LENGTH (2*sizeof(ip_addr))
 static inline void set_next_hop(byte *b, ip_addr addr) { ((ip_addr *) b)[0] = addr; ((ip_addr *) b)[1] = IPA_NONE; }
-#else
 #define NEXT_HOP_LENGTH sizeof(ip_addr)
 static inline void set_next_hop(byte *b, ip_addr addr) { ((ip_addr *) b)[0] = addr; }
 #endif
 
-void bgp_attach_attr(struct ea_list **to, struct linpool *pool, unsigned attr, uintptr_t val);
-byte *bgp_attach_attr_wa(struct ea_list **to, struct linpool *pool, unsigned attr, unsigned len);
-struct rta *bgp_decode_attrs(struct bgp_conn *conn, byte *a, uint len, struct linpool *pool, int mandatory);
-int bgp_get_attr(struct eattr *e, byte *buf, int buflen);
+int bgp_encode_attrs(struct bgp_write_state *s, ea_list *attrs, byte *buf, byte *end);
+ea_list * bgp_decode_attrs(struct bgp_parse_state *s, byte *data, uint len);
+
+void bgp_init_bucket_table(struct bgp_channel *c);
+void bgp_free_bucket(struct bgp_channel *c, struct bgp_bucket *b);
+void bgp_defer_bucket(struct bgp_channel *c, struct bgp_bucket *b);
+void bgp_withdraw_bucket(struct bgp_channel *c, struct bgp_bucket *b);
+
+void bgp_init_prefix_table(struct bgp_channel *c);
+void bgp_free_prefix(struct bgp_channel *c, struct bgp_prefix *bp);
+
 int bgp_rte_better(struct rte *, struct rte *);
 int bgp_rte_mergable(rte *pri, rte *sec);
 int bgp_rte_recalculate(rtable *table, net *net, rte *new, rte *old, rte *old_best);
-void bgp_rt_notify(struct proto *P, rtable *tbl UNUSED, net *n, rte *new, rte *old UNUSED, ea_list *attrs);
+void bgp_rt_notify(struct proto *P, struct channel *C, net *n, rte *new, rte *old, ea_list *attrs);
 int bgp_import_control(struct proto *, struct rte **, struct ea_list **, struct linpool *);
-void bgp_init_bucket_table(struct bgp_proto *);
-void bgp_free_bucket(struct bgp_proto *p, struct bgp_bucket *buck);
-void bgp_init_prefix_table(struct bgp_proto *p, u32 order);
-void bgp_free_prefix(struct bgp_proto *p, struct bgp_prefix *bp);
-uint bgp_encode_attrs(struct bgp_proto *p, byte *w, ea_list *attrs, int remains);
+int bgp_get_attr(struct eattr *e, byte *buf, int buflen);
 void bgp_get_route_info(struct rte *, byte *buf, struct ea_list *attrs);
 
-inline static void bgp_attach_attr_ip(struct ea_list **to, struct linpool *pool, unsigned attr, ip_addr a)
-{ *(ip_addr *) bgp_attach_attr_wa(to, pool, attr, sizeof(ip_addr)) = a; }
 
 /* packets.c */
 
 void mrt_dump_bgp_state_change(struct bgp_conn *conn, unsigned old, unsigned new);
-void bgp_schedule_packet(struct bgp_conn *conn, int type);
+const struct bgp_af_desc *bgp_get_af_desc(u32 afi);
+const struct bgp_af_caps *bgp_find_af_caps(struct bgp_caps *caps, u32 afi);
+void bgp_schedule_packet(struct bgp_conn *conn, struct bgp_channel *c, int type);
 void bgp_kick_tx(void *vconn);
 void bgp_tx(struct birdsock *sk);
 int bgp_rx(struct birdsock *sk, uint size);
 const char * bgp_error_dsc(unsigned code, unsigned subcode);
 void bgp_log_error(struct bgp_proto *p, u8 class, char *msg, unsigned code, unsigned subcode, byte *data, unsigned len);
 
+void bgp_update_next_hop(struct bgp_export_state *s, eattr *a, ea_list **to);
+
+
 /* Packet types */
 
 #define PKT_OPEN		0x01
@@ -305,9 +526,9 @@ void bgp_log_error(struct bgp_proto *p, u8 class, char *msg, unsigned code, unsi
 #define BA_RCID_PATH		0x0d
 #define BA_MP_REACH_NLRI	0x0e	/* [RFC2283] */
 #define BA_MP_UNREACH_NLRI	0x0f
-#define BA_EXT_COMMUNITY	0x10	/* [RFC4360] */
-#define BA_AS4_PATH             0x11    /* [RFC4893] */
-#define BA_AS4_AGGREGATOR       0x12
+#define BA_EXT_COMMUNITY	0x10	/* RFC 4360 */
+#define BA_AS4_PATH             0x11	/* RFC 6793 */
+#define BA_AS4_AGGREGATOR       0x12	/* RFC 6793 */
 #define BA_LARGE_COMMUNITY	0x20	/* [draft-ietf-idr-large-community] */
 
 /* BGP connection states */
@@ -328,14 +549,12 @@ void bgp_log_error(struct bgp_proto *p, u8 class, char *msg, unsigned code, unsi
  *
  * When BGP protocol is started by core, it goes to BSS_PREPARE. When BGP
  * protocol done what is neccessary to start itself (like acquiring the lock),
- * it goes to BSS_CONNECT.  When some connection attempt failed because of
- * option or capability error, it goes to BSS_CONNECT_NOCAP.
+ * it goes to BSS_CONNECT.
  */
 
 #define BSS_PREPARE		0	/* Used before ordinary BGP started, i. e. waiting for lock */
 #define BSS_DELAY		1	/* Startup delay due to previous errors */
 #define BSS_CONNECT		2	/* Ordinary BGP connecting */
-#define BSS_CONNECT_NOCAP	3	/* Legacy BGP connecting (without capabilities) */
 
 
 /* BGP feed states (TX)
@@ -344,7 +563,7 @@ void bgp_log_error(struct bgp_proto *p, u8 class, char *msg, unsigned code, unsi
  *
  * RFC 7313 specifies that a route refresh should be demarcated by BoRR and EoRR packets.
  *
- * These states (stored in p->feed_state) are used to keep track of these
+ * These states (stored in c->feed_state) are used to keep track of these
  * requirements. When such feed is started, BFS_LOADING / BFS_REFRESHING is
  * set. When it ended, BFS_LOADED / BFS_REFRESHED is set to schedule End-of-RIB
  * or EoRR packet. When the packet is sent, the state returned to BFS_NONE.
@@ -400,15 +619,5 @@ void bgp_log_error(struct bgp_proto *p, u8 class, char *msg, unsigned code, unsi
 #define ORIGIN_EGP		1
 #define ORIGIN_INCOMPLETE	2
 
-/* Address families */
-
-#define BGP_AF_IPV4		1
-#define BGP_AF_IPV6		2
-
-#ifdef IPV6
-#define BGP_AF BGP_AF_IPV6
-#else
-#define BGP_AF BGP_AF_IPV4
-#endif
 
 #endif
diff --git a/proto/bgp/config.Y b/proto/bgp/config.Y
index bdbb6007..10a338d8 100644
--- a/proto/bgp/config.Y
+++ b/proto/bgp/config.Y
@@ -13,28 +13,32 @@ CF_HDR
 CF_DEFINES
 
 #define BGP_CFG ((struct bgp_config *) this_proto)
+#define BGP_CC ((struct bgp_channel_config *) this_channel)
 
 CF_DECLS
 
-CF_KEYWORDS(BGP, LOCAL, NEIGHBOR, AS, HOLD, TIME, CONNECT, RETRY,
-	KEEPALIVE, MULTIHOP, STARTUP, VIA, NEXT, HOP, SELF, DEFAULT,
-	PATH, METRIC, ERROR, START, DELAY, FORGET, WAIT, ENABLE,
-	DISABLE, AFTER, BGP_PATH, BGP_LOCAL_PREF, BGP_MED, BGP_ORIGIN,
-	BGP_NEXT_HOP, BGP_ATOMIC_AGGR, BGP_AGGREGATOR, BGP_COMMUNITY,
-	BGP_EXT_COMMUNITY, SOURCE, ADDRESS, PASSWORD, RR, RS, CLIENT,
-	CLUSTER, ID, AS4, ADVERTISE, IPV4, CAPABILITIES, LIMIT, PASSIVE,
-	PREFER, OLDER, MISSING, LLADDR, DROP, IGNORE, ROUTE, REFRESH,
-	INTERPRET, COMMUNITIES, BGP_ORIGINATOR_ID, BGP_CLUSTER_LIST, IGP,
-	TABLE, GATEWAY, DIRECT, RECURSIVE, MED, TTL, SECURITY, DETERMINISTIC,
-	SECONDARY, ALLOW, BFD, ADD, PATHS, RX, TX, GRACEFUL, RESTART, AWARE,
-	CHECK, LINK, PORT, EXTENDED, MESSAGES, SETKEY, BGP_LARGE_COMMUNITY)
+CF_KEYWORDS(BGP, LOCAL, NEIGHBOR, AS, HOLD, TIME, CONNECT, RETRY, KEEPALIVE,
+	MULTIHOP, STARTUP, VIA, NEXT, HOP, SELF, DEFAULT, PATH, METRIC, ERROR,
+	START, DELAY, FORGET, WAIT, ENABLE, DISABLE, AFTER, BGP_PATH,
+	BGP_LOCAL_PREF, BGP_MED, BGP_ORIGIN, BGP_NEXT_HOP, BGP_ATOMIC_AGGR,
+	BGP_AGGREGATOR, BGP_COMMUNITY, BGP_EXT_COMMUNITY, BGP_LARGE_COMMUNITY,
+	SOURCE, ADDRESS, PASSWORD, RR, RS, CLIENT, CLUSTER, ID, AS4, ADVERTISE,
+	IPV4, CAPABILITIES, LIMIT, PASSIVE, PREFER, OLDER, MISSING, LLADDR,
+	DROP, IGNORE, ROUTE, REFRESH, INTERPRET, COMMUNITIES, BGP_ORIGINATOR_ID,
+	BGP_CLUSTER_LIST, IGP, TABLE, GATEWAY, DIRECT, RECURSIVE, MED, TTL,
+	SECURITY, DETERMINISTIC, SECONDARY, ALLOW, BFD, ADD, PATHS, RX, TX,
+	GRACEFUL, RESTART, AWARE, CHECK, LINK, PORT, EXTENDED, MESSAGES, SETKEY,
+	STRICT, BIND, CONFEDERATION, MEMBER, MULTICAST)
+
+%type <i32> bgp_afi
 
 CF_GRAMMAR
 
-CF_ADDTO(proto, bgp_proto '}' { bgp_check_config(BGP_CFG); } )
+CF_ADDTO(proto, bgp_proto '}' )
 
 bgp_proto_start: proto_start BGP {
      this_proto = proto_config_new(&proto_bgp, $1);
+     BGP_CFG->local_port = BGP_PORT;
      BGP_CFG->remote_port = BGP_PORT;
      BGP_CFG->multihop = -1;	/* undefined */
      BGP_CFG->hold_time = 240;
@@ -49,26 +53,35 @@ bgp_proto_start: proto_start BGP {
      BGP_CFG->enable_refresh = 1;
      BGP_CFG->enable_as4 = 1;
      BGP_CFG->capabilities = 2;
-     BGP_CFG->advertise_ipv4 = 1;
      BGP_CFG->interpret_communities = 1;
      BGP_CFG->default_local_pref = 100;
      BGP_CFG->gr_mode = BGP_GR_AWARE;
      BGP_CFG->gr_time = 120;
      BGP_CFG->setkey = 1;
- }
+   }
+ ;
+
+bgp_loc_opts:
+   /* empty */
+ | bgp_loc_opts PORT expr { BGP_CFG->local_port = $3; if (($3<1) || ($3>65535)) cf_error("Invalid port number"); }
+ | bgp_loc_opts AS expr { BGP_CFG->local_as = $3; }
  ;
 
 bgp_nbr_opts:
    /* empty */
- | bgp_nbr_opts PORT expr { BGP_CFG->remote_port = $3; if (($3<1) || ($3>65535)) cf_error("Invalid port number");  }
+ | bgp_nbr_opts PORT expr { BGP_CFG->remote_port = $3; if (($3<1) || ($3>65535)) cf_error("Invalid port number"); }
  | bgp_nbr_opts AS expr { BGP_CFG->remote_as = $3; }
  ;
 
 bgp_proto:
    bgp_proto_start proto_name '{'
  | bgp_proto proto_item ';'
- | bgp_proto LOCAL AS expr ';' { BGP_CFG->local_as = $4; }
- | bgp_proto LOCAL ipa AS expr ';' { BGP_CFG->source_addr = $3; BGP_CFG->local_as = $5; }
+ | bgp_proto bgp_proto_channel ';'
+ | bgp_proto LOCAL bgp_loc_opts ';'
+ | bgp_proto LOCAL ipa ipa_scope bgp_loc_opts ';' {
+     BGP_CFG->local_ip = $3;
+     if ($4) BGP_CFG->iface = $4;
+   }
  | bgp_proto NEIGHBOR bgp_nbr_opts ';'
  | bgp_proto NEIGHBOR ipa ipa_scope bgp_nbr_opts ';' {
      if (ipa_nonzero(BGP_CFG->remote_ip))
@@ -78,20 +91,16 @@ bgp_proto:
    }
  | bgp_proto INTERFACE TEXT ';' { BGP_CFG->iface = if_get_by_name($3); }
  | bgp_proto RR CLUSTER ID idval ';' { BGP_CFG->rr_cluster_id = $5; }
- | bgp_proto RR CLIENT ';' { BGP_CFG->rr_client = 1; }
- | bgp_proto RS CLIENT ';' { BGP_CFG->rs_client = 1; }
+ | bgp_proto RR CLIENT bool ';' { BGP_CFG->rr_client = $4; }
+ | bgp_proto RS CLIENT bool ';' { BGP_CFG->rs_client = $4; }
+ | bgp_proto CONFEDERATION expr ';' { BGP_CFG->confederation = $3; }
+ | bgp_proto CONFEDERATION MEMBER bool ';' { BGP_CFG->confederation_member = $4; }
  | bgp_proto HOLD TIME expr ';' { BGP_CFG->hold_time = $4; }
  | bgp_proto STARTUP HOLD TIME expr ';' { BGP_CFG->initial_hold_time = $5; }
  | bgp_proto DIRECT ';' { BGP_CFG->multihop = 0; }
  | bgp_proto MULTIHOP ';' { BGP_CFG->multihop = 64; }
  | bgp_proto MULTIHOP expr ';' { BGP_CFG->multihop = $3; if (($3<1) || ($3>255)) cf_error("Multihop must be in range 1-255"); }
- | bgp_proto NEXT HOP SELF ';' { BGP_CFG->next_hop_self = 1; BGP_CFG->next_hop_keep = 0; }
- | bgp_proto NEXT HOP KEEP ';' { BGP_CFG->next_hop_keep = 1; BGP_CFG->next_hop_self = 0; }
- | bgp_proto MISSING LLADDR SELF ';' { BGP_CFG->missing_lladdr = MLL_SELF; }
- | bgp_proto MISSING LLADDR DROP ';' { BGP_CFG->missing_lladdr = MLL_DROP; }
- | bgp_proto MISSING LLADDR IGNORE ';' { BGP_CFG->missing_lladdr = MLL_IGNORE; }
- | bgp_proto GATEWAY DIRECT ';' { BGP_CFG->gw_mode = GW_DIRECT; }
- | bgp_proto GATEWAY RECURSIVE ';' { BGP_CFG->gw_mode = GW_RECURSIVE; }
+ | bgp_proto STRICT BIND bool ';' { BGP_CFG->strict_bind = $4; }
  | bgp_proto PATH METRIC bool ';' { BGP_CFG->compare_path_lengths = $4; }
  | bgp_proto MED METRIC bool ';' { BGP_CFG->med_metric = $4; }
  | bgp_proto IGP METRIC bool ';' { BGP_CFG->igp_metric = $4; }
@@ -99,7 +108,7 @@ bgp_proto:
  | bgp_proto DETERMINISTIC MED bool ';' { BGP_CFG->deterministic_med = $4; }
  | bgp_proto DEFAULT BGP_MED expr ';' { BGP_CFG->default_med = $4; }
  | bgp_proto DEFAULT BGP_LOCAL_PREF expr ';' { BGP_CFG->default_local_pref = $4; }
- | bgp_proto SOURCE ADDRESS ipa ';' { BGP_CFG->source_addr = $4; }
+ | bgp_proto SOURCE ADDRESS ipa ';' { BGP_CFG->local_ip = $4; }
  | bgp_proto START DELAY TIME expr ';' { BGP_CFG->connect_delay_time = $5; log(L_WARN "%s: Start delay time option is deprecated, use connect delay time", this_proto->name); }
  | bgp_proto CONNECT DELAY TIME expr ';' { BGP_CFG->connect_delay_time = $5; }
  | bgp_proto CONNECT RETRY TIME expr ';' { BGP_CFG->connect_retry_time = $5; }
@@ -111,26 +120,79 @@ bgp_proto:
  | bgp_proto ENABLE AS4 bool ';' { BGP_CFG->enable_as4 = $4; }
  | bgp_proto ENABLE EXTENDED MESSAGES bool ';' { BGP_CFG->enable_extended_messages = $5; }
  | bgp_proto CAPABILITIES bool ';' { BGP_CFG->capabilities = $3; }
- | bgp_proto ADVERTISE IPV4 bool ';' { BGP_CFG->advertise_ipv4 = $4; }
  | bgp_proto PASSWORD text ';' { BGP_CFG->password = $3; }
  | bgp_proto SETKEY bool ';' { BGP_CFG->setkey = $3; }
  | bgp_proto PASSIVE bool ';' { BGP_CFG->passive = $3; }
  | bgp_proto INTERPRET COMMUNITIES bool ';' { BGP_CFG->interpret_communities = $4; }
- | bgp_proto SECONDARY bool ';' { BGP_CFG->secondary = $3; }
- | bgp_proto ADD PATHS RX ';' { BGP_CFG->add_path = ADD_PATH_RX; }
- | bgp_proto ADD PATHS TX ';' { BGP_CFG->add_path = ADD_PATH_TX; }
- | bgp_proto ADD PATHS bool ';' { BGP_CFG->add_path = $4 ? ADD_PATH_FULL : 0; }
  | bgp_proto ALLOW LOCAL AS ';' { BGP_CFG->allow_local_as = -1; }
  | bgp_proto ALLOW LOCAL AS expr ';' { BGP_CFG->allow_local_as = $5; }
  | bgp_proto GRACEFUL RESTART bool ';' { BGP_CFG->gr_mode = $4; }
  | bgp_proto GRACEFUL RESTART AWARE ';' { BGP_CFG->gr_mode = BGP_GR_AWARE; }
  | bgp_proto GRACEFUL RESTART TIME expr ';' { BGP_CFG->gr_time = $5; }
- | bgp_proto IGP TABLE rtable ';' { BGP_CFG->igp_table = $4; }
  | bgp_proto TTL SECURITY bool ';' { BGP_CFG->ttl_security = $4; }
  | bgp_proto CHECK LINK bool ';' { BGP_CFG->check_link = $4; }
  | bgp_proto BFD bool ';' { BGP_CFG->bfd = $3; cf_check_bfd($3); }
  ;
 
+bgp_afi:
+   IPV4 { $$ = BGP_AF_IPV4; }
+ | IPV6 { $$ = BGP_AF_IPV6; }
+ | IPV4 MULTICAST { $$ = BGP_AF_IPV4_MC; }
+ | IPV6 MULTICAST { $$ = BGP_AF_IPV6_MC; }
+ ;
+
+bgp_channel_start: bgp_afi
+{
+  const struct bgp_af_desc *desc = bgp_get_af_desc($1);
+
+  if (!desc)
+    cf_error("Unknown AFI/SAFI");
+
+  this_channel = channel_config_new(&channel_bgp, desc->net, this_proto);
+  BGP_CC->c.name = desc->name;
+  BGP_CC->afi = $1;
+  BGP_CC->gr_able = 0xff;	/* undefined */
+};
+
+bgp_channel_item:
+   channel_item
+ | NEXT HOP ADDRESS ipa { BGP_CC->next_hop_addr = $4; }
+ | NEXT HOP SELF { BGP_CC->next_hop_self = 1; BGP_CC->next_hop_keep = 0; }
+ | NEXT HOP KEEP { BGP_CC->next_hop_keep = 1; BGP_CC->next_hop_self = 0; }
+ | MISSING LLADDR SELF { BGP_CC->missing_lladdr = MLL_SELF; }
+ | MISSING LLADDR DROP { BGP_CC->missing_lladdr = MLL_DROP; }
+ | MISSING LLADDR IGNORE { BGP_CC->missing_lladdr = MLL_IGNORE; }
+ | GATEWAY DIRECT { BGP_CC->gw_mode = GW_DIRECT; }
+ | GATEWAY RECURSIVE { BGP_CC->gw_mode = GW_RECURSIVE; }
+ | SECONDARY bool { BGP_CC->secondary = $2; }
+ | GRACEFUL RESTART bool { BGP_CC->gr_able = $3; }
+ | ADD PATHS RX { BGP_CC->add_path = BGP_ADD_PATH_RX; }
+ | ADD PATHS TX { BGP_CC->add_path = BGP_ADD_PATH_TX; }
+ | ADD PATHS bool { BGP_CC->add_path = $3 ? BGP_ADD_PATH_FULL : 0; }
+ | IGP TABLE rtable { BGP_CC->igp_table = $3; }
+ ;
+
+bgp_channel_opts:
+   /* empty */
+ | bgp_channel_opts bgp_channel_item ';'
+ ;
+
+bgp_channel_opt_list:
+   /* empty */
+ | '{' bgp_channel_opts '}'
+ ;
+
+bgp_channel_end:
+{
+  if (!this_channel->table)
+    cf_error("Routing table not specified");
+
+  this_channel = NULL;
+};
+
+bgp_proto_channel: bgp_channel_start bgp_channel_opt_list bgp_channel_end;
+
+
 CF_ADDTO(dynamic_attr, BGP_ORIGIN
 	{ $$ = f_new_dynamic_attr(EAF_TYPE_INT, T_ENUM_BGP_ORIGIN, EA_CODE(EAP_BGP, BA_ORIGIN)); })
 CF_ADDTO(dynamic_attr, BGP_PATH
diff --git a/proto/bgp/packets.c b/proto/bgp/packets.c
index 3e816839..66561ee4 100644
--- a/proto/bgp/packets.c
+++ b/proto/bgp/packets.c
@@ -2,12 +2,16 @@
  *	BIRD -- BGP Packet Processing
  *
  *	(c) 2000 Martin Mares <mj@ucw.cz>
+ *	(c) 2008--2016 Ondrej Zajicek <santiago@crfreenet.org>
+ *	(c) 2008--2016 CZ.NIC z.s.p.o.
  *
  *	Can be freely distributed and used under the terms of the GNU GPL.
  */
 
 #undef LOCAL_DEBUG
 
+#include <stdlib.h>
+
 #include "nest/bird.h"
 #include "nest/iface.h"
 #include "nest/protocol.h"
@@ -38,6 +42,46 @@ static byte fsm_err_subcode[BS_MAX] = {
   [BS_ESTABLISHED] = 3
 };
 
+
+static struct bgp_channel *
+bgp_get_channel(struct bgp_proto *p, u32 afi)
+{
+  uint i;
+
+  for (i = 0; i < p->channel_count; i++)
+    if (p->afi_map[i] == afi)
+      return p->channel_map[i];
+
+  return NULL;
+}
+
+static inline void
+put_af3(byte *buf, u32 id)
+{
+  put_u16(buf, id >> 16);
+  buf[2] = id & 0xff;
+}
+
+static inline void
+put_af4(byte *buf, u32 id)
+{
+  put_u16(buf, id >> 16);
+  buf[2] = 0;
+  buf[3] = id & 0xff;
+}
+
+static inline u32
+get_af3(byte *buf)
+{
+  return (get_u16(buf) << 16) | buf[2];
+}
+
+static inline u32
+get_af4(byte *buf)
+{
+  return (get_u16(buf) << 16) | buf[3];
+}
+
 /*
  * MRT Dump format is not semantically specified.
  * We will use these values in appropriate fields:
@@ -58,31 +102,41 @@ static byte *
 mrt_put_bgp4_hdr(byte *buf, struct bgp_conn *conn, int as4)
 {
   struct bgp_proto *p = conn->bgp;
+  uint v4 = ipa_is_ip4(p->cf->remote_ip);
 
   if (as4)
-    {
-      put_u32(buf+0, p->remote_as);
-      put_u32(buf+4, p->local_as);
-      buf+=8;
-    }
+  {
+    put_u32(buf+0, p->remote_as);
+    put_u32(buf+4, p->public_as);
+    buf+=8;
+  }
   else
-    {
-      put_u16(buf+0, (p->remote_as <= 0xFFFF) ? p->remote_as : AS_TRANS);
-      put_u16(buf+2, (p->local_as <= 0xFFFF)  ? p->local_as  : AS_TRANS);
-      buf+=4;
-    }
+  {
+    put_u16(buf+0, (p->remote_as <= 0xFFFF) ? p->remote_as : AS_TRANS);
+    put_u16(buf+2, (p->public_as <= 0xFFFF) ? p->public_as : AS_TRANS);
+    buf+=4;
+  }
 
   put_u16(buf+0, (p->neigh && p->neigh->iface) ? p->neigh->iface->index : 0);
-  put_u16(buf+2, BGP_AF);
+  put_u16(buf+2, v4 ? BGP_AFI_IPV4 : BGP_AFI_IPV6);
   buf+=4;
-  buf = put_ipa(buf, conn->sk ? conn->sk->daddr : IPA_NONE);
-  buf = put_ipa(buf, conn->sk ? conn->sk->saddr : IPA_NONE);
+
+  if (v4)
+  {
+    buf = put_ip4(buf, conn->sk ? ipa_to_ip4(conn->sk->daddr) : IP4_NONE);
+    buf = put_ip4(buf, conn->sk ? ipa_to_ip4(conn->sk->saddr) : IP4_NONE);
+  }
+  else
+  {
+    buf = put_ip6(buf, conn->sk ? ipa_to_ip6(conn->sk->daddr) : IP6_NONE);
+    buf = put_ip6(buf, conn->sk ? ipa_to_ip6(conn->sk->saddr) : IP6_NONE);
+  }
 
   return buf;
 }
 
 static void
-mrt_dump_bgp_packet(struct bgp_conn *conn, byte *pkt, unsigned len)
+mrt_dump_bgp_packet(struct bgp_conn *conn, byte *pkt, uint len)
 {
   byte *buf = alloca(128+len);	/* 128 is enough for MRT headers */
   byte *bp = buf + MRTDUMP_HDR_LENGTH;
@@ -96,14 +150,14 @@ mrt_dump_bgp_packet(struct bgp_conn *conn, byte *pkt, unsigned len)
 }
 
 static inline u16
-convert_state(unsigned state)
+convert_state(uint state)
 {
   /* Convert state from our BS_* values to values used in MRTDump */
   return (state == BS_CLOSE) ? 1 : state + 1;
 }
 
 void
-mrt_dump_bgp_state_change(struct bgp_conn *conn, unsigned old, unsigned new)
+mrt_dump_bgp_state_change(struct bgp_conn *conn, uint old, uint new)
 {
   byte buf[128];
   byte *bp = buf + MRTDUMP_HDR_LENGTH;
@@ -127,1298 +181,1675 @@ bgp_create_notification(struct bgp_conn *conn, byte *buf)
   return buf + 2 + conn->notify_size;
 }
 
-#ifdef IPV6
-static byte *
-bgp_put_cap_ipv6(struct bgp_proto *p UNUSED, byte *buf)
-{
-  *buf++ = 1;		/* Capability 1: Multiprotocol extensions */
-  *buf++ = 4;		/* Capability data length */
-  *buf++ = 0;		/* We support AF IPv6 */
-  *buf++ = BGP_AF_IPV6;
-  *buf++ = 0;		/* RFU */
-  *buf++ = 1;		/* and SAFI 1 */
-  return buf;
-}
 
-#else
+/* Capability negotiation as per RFC 5492 */
 
-static byte *
-bgp_put_cap_ipv4(struct bgp_proto *p UNUSED, byte *buf)
-{
-  *buf++ = 1;		/* Capability 1: Multiprotocol extensions */
-  *buf++ = 4;		/* Capability data length */
-  *buf++ = 0;		/* We support AF IPv4 */
-  *buf++ = BGP_AF_IPV4;
-  *buf++ = 0;		/* RFU */
-  *buf++ = 1;		/* and SAFI 1 */
-  return buf;
-}
-#endif
+#define WALK_AF_CAPS(caps,ac) \
+  for (ac = caps->af_data; ac < &caps->af_data[caps->af_count]; ac++)
 
-static byte *
-bgp_put_cap_rr(struct bgp_proto *p UNUSED, byte *buf)
+const struct bgp_af_caps *
+bgp_find_af_caps(struct bgp_caps *caps, u32 afi)
 {
-  *buf++ = 2;		/* Capability 2: Support for route refresh */
-  *buf++ = 0;		/* Capability data length */
-  return buf;
-}
+  struct bgp_af_caps *ac;
 
-static byte *
-bgp_put_cap_ext_msg(struct bgp_proto *p UNUSED, byte *buf)
-{
-  *buf++ = 6;		/* Capability 6: Support for extended messages */
-  *buf++ = 0;		/* Capability data length */
-  return buf;
+  WALK_AF_CAPS(caps, ac)
+    if (ac->afi == afi)
+      return ac;
+
+  return NULL;
 }
 
-static byte *
-bgp_put_cap_gr1(struct bgp_proto *p, byte *buf)
+static struct bgp_af_caps *
+bgp_get_af_caps(struct bgp_caps *caps, u32 afi)
 {
-  *buf++ = 64;		/* Capability 64: Support for graceful restart */
-  *buf++ = 6;		/* Capability data length */
+  struct bgp_af_caps *ac;
 
-  put_u16(buf, p->cf->gr_time);
-  if (p->p.gr_recovery)
-    buf[0] |= BGP_GRF_RESTART;
-  buf += 2;
+  WALK_AF_CAPS(caps, ac)
+    if (ac->afi == afi)
+      return ac;
 
-  *buf++ = 0;		/* Appropriate AF */
-  *buf++ = BGP_AF;
-  *buf++ = 1;		/* and SAFI 1 */
-  *buf++ = p->p.gr_recovery ? BGP_GRF_FORWARDING : 0;
+  ac = &caps->af_data[caps->af_count++];
+  memset(ac, 0, sizeof(struct bgp_af_caps));
+  ac->afi = afi;
 
-  return buf;
+  return ac;
 }
 
-static byte *
-bgp_put_cap_gr2(struct bgp_proto *p UNUSED, byte *buf)
+static int
+bgp_af_caps_cmp(const void *X, const void *Y)
 {
-  *buf++ = 64;		/* Capability 64: Support for graceful restart */
-  *buf++ = 2;		/* Capability data length */
-  put_u16(buf, 0);
-  return buf + 2;
+  const struct bgp_af_caps *x = X, *y = Y;
+  return (x->afi < y->afi) ? -1 : (x->afi > y->afi) ? 1 : 0;
 }
 
-static byte *
-bgp_put_cap_as4(struct bgp_proto *p, byte *buf)
-{
-  *buf++ = 65;		/* Capability 65: Support for 4-octet AS number */
-  *buf++ = 4;		/* Capability data length */
-  put_u32(buf, p->local_as);
-  return buf + 4;
-}
 
 static byte *
-bgp_put_cap_add_path(struct bgp_proto *p, byte *buf)
+bgp_write_capabilities(struct bgp_conn *conn, byte *buf)
 {
-  *buf++ = 69;		/* Capability 69: Support for ADD-PATH */
-  *buf++ = 4;		/* Capability data length */
+  struct bgp_proto *p = conn->bgp;
+  struct bgp_channel *c;
+  struct bgp_caps *caps;
+  struct bgp_af_caps *ac;
+  uint any_add_path = 0;
+  byte *data;
 
-  *buf++ = 0;		/* Appropriate AF */
-  *buf++ = BGP_AF;
-  *buf++ = 1;		/* SAFI 1 */
+  /* Prepare bgp_caps structure */
 
-  *buf++ = p->cf->add_path;
+  int n = list_length(&p->p.channels);
+  caps = mb_allocz(p->p.pool, sizeof(struct bgp_caps) + n * sizeof(struct bgp_af_caps));
+  conn->local_caps = caps;
 
-  return buf;
-}
+  caps->as4_support = p->cf->enable_as4;
+  caps->ext_messages = p->cf->enable_extended_messages;
+  caps->route_refresh = p->cf->enable_refresh;
+  caps->enhanced_refresh = p->cf->enable_refresh;
 
-static byte *
-bgp_put_cap_err(struct bgp_proto *p UNUSED, byte *buf)
-{
-  *buf++ = 70;		/* Capability 70: Support for enhanced route refresh */
-  *buf++ = 0;		/* Capability data length */
-  return buf;
-}
+  if (caps->as4_support)
+    caps->as4_number = p->public_as;
 
+  if (p->cf->gr_mode)
+  {
+    caps->gr_aware = 1;
+    caps->gr_time = p->cf->gr_time;
+    caps->gr_flags = p->p.gr_recovery ? BGP_GRF_RESTART : 0;
+  }
 
-static byte *
-bgp_create_open(struct bgp_conn *conn, byte *buf)
-{
-  struct bgp_proto *p = conn->bgp;
-  byte *cap;
-  int cap_len;
+  /* Allocate and fill per-AF fields */
+  WALK_LIST(c, p->p.channels)
+  {
+    ac = &caps->af_data[caps->af_count++];
+    ac->afi = c->afi;
+    ac->ready = 1;
 
-  BGP_TRACE(D_PACKETS, "Sending OPEN(ver=%d,as=%d,hold=%d,id=%08x)",
-	    BGP_VERSION, p->local_as, p->cf->hold_time, p->local_id);
-  buf[0] = BGP_VERSION;
-  put_u16(buf+1, (p->local_as < 0xFFFF) ? p->local_as : AS_TRANS);
-  put_u16(buf+3, p->cf->hold_time);
-  put_u32(buf+5, p->local_id);
+    ac->add_path = c->cf->add_path;
+    any_add_path |= ac->add_path;
 
-  if (conn->start_state == BSS_CONNECT_NOCAP)
+    if (c->cf->gr_able)
     {
-      BGP_TRACE(D_PACKETS, "Skipping capabilities");
-      buf[9] = 0;
-      return buf + 10;
+      ac->gr_able = 1;
+
+      if (p->p.gr_recovery)
+	ac->gr_af_flags |= BGP_GRF_FORWARDING;
     }
+  }
 
-  /* Skipped 3 B for length field and Capabilities parameter header */
-  cap = buf + 12;
+  /* Sort capability fields by AFI/SAFI */
+  qsort(caps->af_data, caps->af_count, sizeof(struct bgp_af_caps), bgp_af_caps_cmp);
 
-#ifndef IPV6
-  if (p->cf->advertise_ipv4)
-    cap = bgp_put_cap_ipv4(p, cap);
-#endif
 
-#ifdef IPV6
-  cap = bgp_put_cap_ipv6(p, cap);
-#endif
+  /* Create capability list in buffer */
+
+  WALK_AF_CAPS(caps, ac)
+    if (ac->ready)
+    {
+      *buf++ = 1;		/* Capability 1: Multiprotocol extensions */
+      *buf++ = 4;		/* Capability data length */
+      put_af4(buf, ac->afi);
+      buf += 4;
+    }
+
+  if (caps->route_refresh)
+  {
+    *buf++ = 2;			/* Capability 2: Support for route refresh */
+    *buf++ = 0;			/* Capability data length */
+  }
+
+  if (caps->ext_messages)
+  {
+    *buf++ = 6;			/* Capability 6: Support for extended messages */
+    *buf++ = 0;			/* Capability data length */
+  }
 
-  if (p->cf->enable_refresh)
-    cap = bgp_put_cap_rr(p, cap);
+  if (caps->gr_aware)
+  {
+    *buf++ = 64;		/* Capability 64: Support for graceful restart */
+    *buf++ = 0;			/* Capability data length, will be fixed later */
+    data = buf;
 
-  if (p->cf->gr_mode == BGP_GR_ABLE)
-    cap = bgp_put_cap_gr1(p, cap);
-  else if (p->cf->gr_mode == BGP_GR_AWARE)
-    cap = bgp_put_cap_gr2(p, cap);
+    put_u16(buf, caps->gr_time);
+    buf[0] |= caps->gr_flags;
+    buf += 2;
 
-  if (p->cf->enable_as4)
-    cap = bgp_put_cap_as4(p, cap);
+    WALK_AF_CAPS(caps, ac)
+      if (ac->gr_able)
+      {
+	put_af3(buf, ac->afi);
+	buf[3] = ac->gr_af_flags;
+	buf += 4;
+      }
 
-  if (p->cf->add_path)
-    cap = bgp_put_cap_add_path(p, cap);
+    data[-1] = buf - data;
+  }
 
-  if (p->cf->enable_refresh)
-    cap = bgp_put_cap_err(p, cap);
+  if (caps->as4_support)
+  {
+    *buf++ = 65;		/* Capability 65: Support for 4-octet AS number */
+    *buf++ = 4;			/* Capability data length */
+    put_u32(buf, p->public_as);
+    buf += 4;
+  }
 
-  if (p->cf->enable_extended_messages)
-    cap = bgp_put_cap_ext_msg(p, cap);
+  if (any_add_path)
+  {
+    *buf++ = 69;		/* Capability 69: Support for ADD-PATH */
+    *buf++ = 0;			/* Capability data length, will be fixed later */
+    data = buf;
 
-  cap_len = cap - buf - 12;
-  if (cap_len > 0)
-    {
-      buf[9]  = cap_len + 2;	/* Optional params len */
-      buf[10] = 2;		/* Option: Capability list */
-      buf[11] = cap_len;	/* Option length */
-      return cap;
-    }
-  else
-    {
-      buf[9] = 0;		/* No optional parameters */
-      return buf + 10;
-    }
-}
+    WALK_AF_CAPS(caps, ac)
+      if (ac->add_path)
+      {
+	put_af3(buf, ac->afi);
+	buf[3] = ac->add_path;
+	buf += 4;
+      }
 
-static uint
-bgp_encode_prefixes(struct bgp_proto *p, byte *w, struct bgp_bucket *buck, uint remains)
-{
-  byte *start = w;
-  ip_addr a;
-  int bytes;
+    data[-1] = buf - data;
+  }
 
-  while (!EMPTY_LIST(buck->prefixes) && (remains >= (5+sizeof(ip_addr))))
-    {
-      struct bgp_prefix *px = SKIP_BACK(struct bgp_prefix, bucket_node, HEAD(buck->prefixes));
-      DBG("\tDequeued route %I/%d\n", px->n.prefix, px->n.pxlen);
+  if (caps->enhanced_refresh)
+  {
+    *buf++ = 70;		/* Capability 70: Support for enhanced route refresh */
+    *buf++ = 0;			/* Capability data length */
+  }
 
-      if (p->add_path_tx)
-	{
-	  put_u32(w, px->path_id);
-	  w += 4;
-	  remains -= 4;
-	}
+  /* FIXME: Should not XXXX 255 */
 
-      *w++ = px->n.pxlen;
-      bytes = (px->n.pxlen + 7) / 8;
-      a = px->n.prefix;
-      ipa_hton(a);
-      memcpy(w, &a, bytes);
-      w += bytes;
-      remains -= bytes + 1;
-      rem_node(&px->bucket_node);
-      bgp_free_prefix(p, px);
-      // fib_delete(&p->prefix_fib, px);
-    }
-  return w - start;
+  return buf;
 }
 
 static void
-bgp_flush_prefixes(struct bgp_proto *p, struct bgp_bucket *buck)
+bgp_read_capabilities(struct bgp_conn *conn, struct bgp_caps *caps, byte *pos, int len)
 {
-  while (!EMPTY_LIST(buck->prefixes))
-    {
-      struct bgp_prefix *px = SKIP_BACK(struct bgp_prefix, bucket_node, HEAD(buck->prefixes));
-      log(L_ERR "%s: - route %I/%d skipped", p->p.name, px->n.prefix, px->n.pxlen);
-      rem_node(&px->bucket_node);
-      bgp_free_prefix(p, px);
-      // fib_delete(&p->prefix_fib, px);
-    }
-}
+  struct bgp_proto *p = conn->bgp;
+  struct bgp_af_caps *ac;
+  int i, cl;
+  u32 af;
 
-#ifndef IPV6		/* IPv4 version */
+  while (len > 0)
+  {
+    if (len < 2 || len < (2 + pos[1]))
+      goto err;
 
-static byte *
-bgp_create_update(struct bgp_conn *conn, byte *buf)
-{
-  struct bgp_proto *p = conn->bgp;
-  struct bgp_bucket *buck;
-  int remains = bgp_max_packet_length(p) - BGP_HEADER_LENGTH - 4;
-  byte *w;
-  int wd_size = 0;
-  int r_size = 0;
-  int a_size = 0;
-
-  w = buf+2;
-  if ((buck = p->withdraw_bucket) && !EMPTY_LIST(buck->prefixes))
-    {
-      DBG("Withdrawn routes:\n");
-      wd_size = bgp_encode_prefixes(p, w, buck, remains);
-      w += wd_size;
-      remains -= wd_size;
-    }
-  put_u16(buf, wd_size);
+    /* Capability length */
+    cl = pos[1];
 
-  if (!wd_size)
+    /* Capability type */
+    switch (pos[0])
     {
-      while ((buck = (struct bgp_bucket *) HEAD(p->bucket_queue))->send_node.next)
+    case  1: /* Multiprotocol capability, RFC 4760 */
+      if (cl != 4)
+	goto err;
+
+      af = get_af4(pos+2);
+      ac = bgp_get_af_caps(caps, af);
+      ac->ready = 1;
+      break;
+
+    case  2: /* Route refresh capability, RFC 2918 */
+      if (cl != 0)
+	goto err;
+
+      caps->route_refresh = 1;
+      break;
+
+    case  6: /* Extended message length capability, RFC draft */
+      if (cl != 0)
+	goto err;
+
+      caps->ext_messages = 1;
+      break;
+
+    case 64: /* Graceful restart capability, RFC 4724 */
+      if (cl % 4 != 2)
+	goto err;
+
+      /* Only the last instance is valid */
+      WALK_AF_CAPS(caps, ac)
+      {
+	ac->gr_able = 0;
+	ac->gr_af_flags = 0;
+      }
+
+      caps->gr_aware = 1;
+      caps->gr_flags = pos[2] & 0xf0;
+      caps->gr_time = get_u16(pos + 2) & 0x0fff;
+
+      for (i = 2; i < cl; i += 4)
+      {
+	af = get_af3(pos+2+i);
+	ac = bgp_get_af_caps(caps, af);
+	ac->gr_able = 1;
+	ac->gr_af_flags = pos[2+i+3];
+      }
+      break;
+
+    case 65: /* AS4 capability, RFC 4893 */
+      if (cl != 4)
+	goto err;
+
+      caps->as4_support = 1;
+      caps->as4_number = get_u32(pos + 2);
+      break;
+
+    case 69: /* ADD-PATH capability, RFC 7911 */
+      if (cl % 4)
+	goto err;
+
+      for (i = 0; i < cl; i += 4)
+      {
+	byte val = pos[2+i+3];
+	if (!val || (val > BGP_ADD_PATH_FULL))
 	{
-	  if (EMPTY_LIST(buck->prefixes))
-	    {
-	      DBG("Deleting empty bucket %p\n", buck);
-	      rem_node(&buck->send_node);
-	      bgp_free_bucket(p, buck);
-	      continue;
-	    }
-
-	  DBG("Processing bucket %p\n", buck);
-	  a_size = bgp_encode_attrs(p, w+2, buck->eattrs, remains - 1024);
-
-	  if (a_size < 0)
-	    {
-	      log(L_ERR "%s: Attribute list too long, skipping corresponding routes", p->p.name);
-	      bgp_flush_prefixes(p, buck);
-	      rem_node(&buck->send_node);
-	      bgp_free_bucket(p, buck);
-	      continue;
-	    }
-
-	  put_u16(w, a_size);
-	  w += a_size + 2;
-	  r_size = bgp_encode_prefixes(p, w, buck, remains - a_size);
-	  w += r_size;
+	  log(L_WARN "%s: Got ADD-PATH capability with unknown value %u, ignoring",
+	      p->p.name, val);
 	  break;
 	}
+      }
+
+      for (i = 0; i < cl; i += 4)
+      {
+	af = get_af3(pos+2+i);
+	ac = bgp_get_af_caps(caps, af);
+	ac->add_path = pos[2+i+3];
+      }
+      break;
+
+    case 70: /* Enhanced route refresh capability, RFC 7313 */
+      if (cl != 0)
+	goto err;
+
+      caps->enhanced_refresh = 1;
+      break;
+
+      /* We can safely ignore all other capabilities */
     }
-  if (!a_size)				/* Attributes not already encoded */
+
+    ADVANCE(pos, len, 2 + cl);
+  }
+  return;
+
+err:
+  bgp_error(conn, 2, 0, NULL, 0);
+  return;
+}
+
+static int
+bgp_read_options(struct bgp_conn *conn, byte *pos, int len)
+{
+  struct bgp_proto *p = conn->bgp;
+  struct bgp_caps *caps;
+  int ol;
+
+  /* Max number of announced AFIs is limited by max option length (255) */
+  caps = alloca(sizeof(struct bgp_caps) + 64 * sizeof(struct bgp_af_caps));
+  memset(caps, 0, sizeof(struct bgp_caps));
+
+  while (len > 0)
+  {
+    if ((len < 2) || (len < (2 + pos[1])))
+    { bgp_error(conn, 2, 0, NULL, 0); return -1; }
+
+    ol = pos[1];
+    if (pos[0] == 2)
     {
-      put_u16(w, 0);
-      w += 2;
+      /* BGP capabilities, RFC 5492 */
+      if (p->cf->capabilities)
+	bgp_read_capabilities(conn, caps, pos + 2, ol);
     }
-  if (wd_size || r_size)
+    else
     {
-      BGP_TRACE_RL(&rl_snd_update, D_PACKETS, "Sending UPDATE");
-      return w;
+      /* Unknown option */
+      bgp_error(conn, 2, 4, pos, ol); /* FIXME: ol or ol+2 ? */
+      return -1;
     }
-  else
-    return NULL;
+
+    ADVANCE(pos, len, 2 + ol);
+  }
+
+  uint n = sizeof(struct bgp_caps) + caps->af_count * sizeof(struct bgp_af_caps);
+  conn->remote_caps = mb_allocz(p->p.pool, n);
+  memcpy(conn->remote_caps, caps, n);
+
+  return 0;
 }
 
 static byte *
-bgp_create_end_mark(struct bgp_conn *conn, byte *buf)
+bgp_create_open(struct bgp_conn *conn, byte *buf)
 {
   struct bgp_proto *p = conn->bgp;
-  BGP_TRACE(D_PACKETS, "Sending END-OF-RIB");
 
-  put_u32(buf, 0);
-  return buf+4;
-}
+  BGP_TRACE(D_PACKETS, "Sending OPEN(ver=%d,as=%d,hold=%d,id=%08x)",
+	    BGP_VERSION, p->public_as, p->cf->hold_time, p->local_id);
+
+  buf[0] = BGP_VERSION;
+  put_u16(buf+1, (p->public_as < 0xFFFF) ? p->public_as : AS_TRANS);
+  put_u16(buf+3, p->cf->hold_time);
+  put_u32(buf+5, p->local_id);
 
-#else		/* IPv6 version */
+  if (p->cf->capabilities)
+  {
+    /* Prepare local_caps and write capabilities to buffer */
+    byte *end = bgp_write_capabilities(conn, buf+12);
+    uint len = end - (buf+12);
 
-static inline int
-same_iface(struct bgp_proto *p, ip_addr *ip)
-{
-  neighbor *n = neigh_find(&p->p, ip, 0);
-  return n && p->neigh && n->iface == p->neigh->iface;
+    buf[9] = len + 2;		/* Optional parameters length */
+    buf[10] = 2;		/* Option 2: Capability list */
+    buf[11] = len;		/* Option data length */
+
+    return end;
+  }
+  else
+  {
+    /* Prepare empty local_caps */
+    conn->local_caps = mb_allocz(p->p.pool, sizeof(struct bgp_caps));
+
+    buf[9] = 0;			/* No optional parameters */
+    return buf + 10;
+  }
+
+  return buf;
 }
 
-static byte *
-bgp_create_update(struct bgp_conn *conn, byte *buf)
+static void
+bgp_rx_open(struct bgp_conn *conn, byte *pkt, uint len)
 {
   struct bgp_proto *p = conn->bgp;
-  struct bgp_bucket *buck;
-  int size, second, rem_stored;
-  int remains = bgp_max_packet_length(p) - BGP_HEADER_LENGTH - 4;
-  byte *w, *w_stored, *tmp, *tstart;
-  ip_addr *ipp, ip, ip_ll;
-  ea_list *ea;
-  eattr *nh;
+  struct bgp_conn *other;
+  u32 asn, hold, id;
 
-  put_u16(buf, 0);
-  w = buf+4;
+  /* Check state */
+  if (conn->state != BS_OPENSENT)
+  { bgp_error(conn, 5, fsm_err_subcode[conn->state], NULL, 0); return; }
 
-  if ((buck = p->withdraw_bucket) && !EMPTY_LIST(buck->prefixes))
-    {
-      DBG("Withdrawn routes:\n");
-      tmp = bgp_attach_attr_wa(&ea, bgp_linpool, BA_MP_UNREACH_NLRI, remains-8);
-      *tmp++ = 0;
-      *tmp++ = BGP_AF_IPV6;
-      *tmp++ = 1;
-      ea->attrs[0].u.ptr->length = 3 + bgp_encode_prefixes(p, tmp, buck, remains-11);
-      size = bgp_encode_attrs(p, w, ea, remains);
-      ASSERT(size >= 0);
-      w += size;
-      remains -= size;
-    }
+  /* Check message contents */
+  if (len < 29 || len != 29 + (uint) pkt[28])
+  { bgp_error(conn, 1, 2, pkt+16, 2); return; }
+
+  if (pkt[19] != BGP_VERSION)
+  { u16 val = BGP_VERSION; bgp_error(conn, 2, 1, (byte *) &val, 2); return; }
+
+  asn = get_u16(pkt+20);
+  hold = get_u16(pkt+22);
+  id = get_u32(pkt+24);
+  BGP_TRACE(D_PACKETS, "Got OPEN(as=%d,hold=%d,id=%R)", asn, hold, id);
+
+  if (bgp_read_options(conn, pkt+29, pkt[28]) < 0)
+    return;
+
+  if (hold > 0 && hold < 3)
+  { bgp_error(conn, 2, 6, pkt+22, 2); return; }
+
+  /* RFC 6286 2.2 - router ID is nonzero and AS-wide unique */
+  if (!id || (p->is_internal && id == p->local_id))
+  { bgp_error(conn, 2, 3, pkt+24, -4); return; }
+
+  struct bgp_caps *caps = conn->remote_caps;
+
+  if (caps->as4_support)
+  {
+    u32 as4 = caps->as4_number;
+
+    if ((as4 != asn) && (asn != AS_TRANS))
+      log(L_WARN "%s: Peer advertised inconsistent AS numbers", p->p.name);
+
+    if (as4 != p->remote_as)
+    { as4 = htonl(as4); bgp_error(conn, 2, 2, (byte *) &as4, 4); return; }
+  }
   else
-    {
-      while ((buck = (struct bgp_bucket *) HEAD(p->bucket_queue))->send_node.next)
-	{
-	  if (EMPTY_LIST(buck->prefixes))
-	    {
-	      DBG("Deleting empty bucket %p\n", buck);
-	      rem_node(&buck->send_node);
-	      bgp_free_bucket(p, buck);
-	      continue;
-	    }
-
-	  DBG("Processing bucket %p\n", buck);
-	  rem_stored = remains;
-	  w_stored = w;
-
-	  size = bgp_encode_attrs(p, w, buck->eattrs, remains - 1024);
-	  if (size < 0)
-	    {
-	      log(L_ERR "%s: Attribute list too long, skipping corresponding routes", p->p.name);
-	      bgp_flush_prefixes(p, buck);
-	      rem_node(&buck->send_node);
-	      bgp_free_bucket(p, buck);
-	      continue;
-	    }
-	  w += size;
-	  remains -= size;
-
-	  /* We have two addresses here in NEXT_HOP eattr. Really.
-	     Unless NEXT_HOP was modified by filter */
-	  nh = ea_find(buck->eattrs, EA_CODE(EAP_BGP, BA_NEXT_HOP));
-	  ASSERT(nh);
-	  second = (nh->u.ptr->length == NEXT_HOP_LENGTH);
-	  ipp = (ip_addr *) nh->u.ptr->data;
-	  ip = ipp[0];
-	  ip_ll = IPA_NONE;
-
-	  if (ipa_equal(ip, p->source_addr))
-	    ip_ll = p->local_link;
-	  else
-	    {
-	      /* If we send a route with 'third party' next hop destinated 
-	       * in the same interface, we should also send a link local 
-	       * next hop address. We use the received one (stored in the 
-	       * other part of BA_NEXT_HOP eattr). If we didn't received
-	       * it (for example it is a static route), we can't use
-	       * 'third party' next hop and we have to use local IP address
-	       * as next hop. Sending original next hop address without
-	       * link local address seems to be a natural way to solve that
-	       * problem, but it is contrary to RFC 2545 and Quagga does not
-	       * accept such routes.
-	       *
-	       * There are two cases, either we have global IP, or
-	       * IPA_NONE if the neighbor is link-local. For IPA_NONE,
-	       * we suppose it is on the same iface, see bgp_update_attrs().
-	       */
-
-	      if (ipa_zero(ip) || same_iface(p, &ip))
-		{
-		  if (second && ipa_nonzero(ipp[1]))
-		    ip_ll = ipp[1];
-		  else
-		    {
-		      switch (p->cf->missing_lladdr)
-			{
-			case MLL_SELF:
-			  ip = p->source_addr;
-			  ip_ll = p->local_link;
-			  break;
-			case MLL_DROP:
-			  log(L_ERR "%s: Missing link-local next hop address, skipping corresponding routes", p->p.name);
-			  w = w_stored;
-			  remains = rem_stored;
-			  bgp_flush_prefixes(p, buck);
-			  rem_node(&buck->send_node);
-			  bgp_free_bucket(p, buck);
-			  continue;
-			case MLL_IGNORE:
-			  break;
-			}
-		    }
-		}
-	    }
-
-	  tstart = tmp = bgp_attach_attr_wa(&ea, bgp_linpool, BA_MP_REACH_NLRI, remains-8);
-	  *tmp++ = 0;
-	  *tmp++ = BGP_AF_IPV6;
-	  *tmp++ = 1;
-
-	  if (ipa_is_link_local(ip))
-	    ip = IPA_NONE;
-
-	  if (ipa_nonzero(ip_ll))
-	    {
-	      *tmp++ = 32;
-	      ipa_hton(ip);
-	      memcpy(tmp, &ip, 16);
-	      ipa_hton(ip_ll);
-	      memcpy(tmp+16, &ip_ll, 16);
-	      tmp += 32;
-	    }
-	  else
-	    {
-	      *tmp++ = 16;
-	      ipa_hton(ip);
-	      memcpy(tmp, &ip, 16);
-	      tmp += 16;
-	    }
-
-	  *tmp++ = 0;			/* No SNPA information */
-	  tmp += bgp_encode_prefixes(p, tmp, buck, remains - (8+3+32+1));
-	  ea->attrs[0].u.ptr->length = tmp - tstart;
-	  size = bgp_encode_attrs(p, w, ea, remains);
-	  ASSERT(size >= 0);
-	  w += size;
-	  break;
-	}
-    }
+  {
+    if (asn != p->remote_as)
+    { bgp_error(conn, 2, 2, pkt+20, 2); return; }
+  }
+
+  /* Check the other connection */
+  other = (conn == &p->outgoing_conn) ? &p->incoming_conn : &p->outgoing_conn;
+  switch (other->state)
+  {
+  case BS_CONNECT:
+  case BS_ACTIVE:
+    /* Stop outgoing connection attempts */
+    bgp_conn_enter_idle_state(other);
+    break;
 
-  size = w - (buf+4);
-  put_u16(buf+2, size);
-  lp_flush(bgp_linpool);
-  if (size)
+  case BS_IDLE:
+  case BS_OPENSENT:
+  case BS_CLOSE:
+    break;
+
+  case BS_OPENCONFIRM:
+    /*
+     * Description of collision detection rules in RFC 4271 is confusing and
+     * contradictory, but it is essentially:
+     *
+     * 1. Router with higher ID is dominant
+     * 2. If both have the same ID, router with higher ASN is dominant [RFC6286]
+     * 3. When both connections are in OpenConfirm state, one initiated by
+     *    the dominant router is kept.
+     *
+     * The first line in the expression below evaluates whether the neighbor
+     * is dominant, the second line whether the new connection was initiated
+     * by the neighbor. If both are true (or both are false), we keep the new
+     * connection, otherwise we keep the old one.
+     */
+    if (((p->local_id < id) || ((p->local_id == id) && (p->public_as < p->remote_as)))
+	== (conn == &p->incoming_conn))
     {
-      BGP_TRACE_RL(&rl_snd_update, D_PACKETS, "Sending UPDATE");
-      return w;
+      /* Should close the other connection */
+      BGP_TRACE(D_EVENTS, "Connection collision, giving up the other connection");
+      bgp_error(other, 6, 7, NULL, 0);
+      break;
     }
-  else
-    return NULL;
+    /* Fall thru */
+  case BS_ESTABLISHED:
+    /* Should close this connection */
+    BGP_TRACE(D_EVENTS, "Connection collision, giving up this connection");
+    bgp_error(conn, 6, 7, NULL, 0);
+    return;
+
+  default:
+    bug("bgp_rx_open: Unknown state");
+  }
+
+  /* Update our local variables */
+  conn->hold_time = MIN(hold, p->cf->hold_time);
+  conn->keepalive_time = p->cf->keepalive_time ? : conn->hold_time / 3;
+  conn->as4_session = conn->local_caps->as4_support && caps->as4_support;
+  conn->ext_messages = conn->local_caps->ext_messages && caps->ext_messages;
+  p->remote_id = id;
+
+  DBG("BGP: Hold timer set to %d, keepalive to %d, AS to %d, ID to %x, AS4 session to %d\n",
+      conn->hold_time, conn->keepalive_time, p->remote_as, p->remote_id, conn->as4_session);
+
+  bgp_schedule_packet(conn, NULL, PKT_KEEPALIVE);
+  bgp_start_timer(conn->hold_timer, conn->hold_time);
+  bgp_conn_enter_openconfirm_state(conn);
 }
 
-static byte *
-bgp_create_end_mark(struct bgp_conn *conn, byte *buf)
+
+/*
+ *	Next hop handling
+ */
+
+#define REPORT(msg, args...) \
+  ({ log(L_REMOTE "%s: " msg, s->proto->p.name, ## args); })
+
+#define WITHDRAW(msg, args...) \
+  ({ REPORT(msg, ## args); s->err_withdraw = 1; return; })
+
+#define BAD_NEXT_HOP	"Invalid NEXT_HOP attribute"
+#define NO_NEXT_HOP	"Missing NEXT_HOP attribute"
+
+
+static void
+bgp_apply_next_hop(struct bgp_parse_state *s, rta *a, ip_addr gw, ip_addr ll)
 {
-  struct bgp_proto *p = conn->bgp;
-  BGP_TRACE(D_PACKETS, "Sending END-OF-RIB");
+  struct bgp_proto *p = s->proto;
+  struct bgp_channel *c = s->channel;
 
-  put_u16(buf+0, 0);
-  put_u16(buf+2, 6);	/* length 4-9 */
-  buf += 4;
+  if (c->cf->gw_mode == GW_DIRECT)
+  {
+    neighbor *nbr = NULL;
+
+    /* GW_DIRECT -> single_hop -> p->neigh != NULL */
+    if (ipa_nonzero(gw))
+      nbr = neigh_find2(&p->p, &gw, NULL, 0);
+    else if (ipa_nonzero(ll))
+      nbr = neigh_find2(&p->p, &ll, p->neigh->iface, 0);
+
+    if (!nbr || (nbr->scope == SCOPE_HOST))
+      WITHDRAW(BAD_NEXT_HOP);
+
+    a->dest = RTD_ROUTER;
+    a->gw = nbr->addr;
+    a->iface = nbr->iface;
+    a->hostentry = NULL;
+    a->igp_metric = 0;
+  }
+  else /* GW_RECURSIVE */
+  {
+    if (ipa_zero(gw))
+      WITHDRAW(BAD_NEXT_HOP);
 
-  /* Empty MP_UNREACH_NLRI atribute */
-  *buf++ = BAF_OPTIONAL;
-  *buf++ = BA_MP_UNREACH_NLRI;
-  *buf++ = 3;		/* Length 7-9 */
-  *buf++ = 0;		/* AFI */
-  *buf++ = BGP_AF_IPV6;
-  *buf++ = 1;		/* SAFI */
-  return buf;
+    rta_set_recursive_next_hop(c->c.table, a, c->igp_table, gw, ll);
+  }
 }
 
-#endif
-
-static inline byte *
-bgp_create_route_refresh(struct bgp_conn *conn, byte *buf)
+static inline int
+bgp_use_next_hop(struct bgp_export_state *s, eattr *a)
 {
-  struct bgp_proto *p = conn->bgp;
-  BGP_TRACE(D_PACKETS, "Sending ROUTE-REFRESH");
+  struct bgp_proto *p = s->proto;
+  ip_addr *nh = (void *) a->u.ptr->data;
 
-  /* Original original route refresh request, RFC 2918 */
-  *buf++ = 0;
-  *buf++ = BGP_AF;
-  *buf++ = BGP_RR_REQUEST;
-  *buf++ = 1;		/* SAFI */
-  return buf;
+  if (s->channel->cf->next_hop_self)
+    return 0;
+
+  if (s->channel->cf->next_hop_keep)
+    return 1;
+
+  /* Keep it when explicitly set in export filter */
+  if (a->type & EAF_FRESH)
+    return 1;
+
+  /* Keep it when exported to internal peers */
+  if (p->is_interior && ipa_nonzero(*nh))
+    return 1;
+
+  /* Keep it when forwarded between single-hop BGPs on the same iface */
+  struct iface *ifa = (s->src && s->src->neigh) ? s->src->neigh->iface : NULL;
+  return p->neigh && (p->neigh->iface == ifa);
 }
 
-static inline byte *
-bgp_create_begin_refresh(struct bgp_conn *conn, byte *buf)
+static inline int
+bgp_use_gateway(struct bgp_export_state *s)
 {
-  struct bgp_proto *p = conn->bgp;
-  BGP_TRACE(D_PACKETS, "Sending BEGIN-OF-RR");
+  struct bgp_proto *p = s->proto;
+  rta *ra = s->route->attrs;
 
-  /* Demarcation of beginning of route refresh (BoRR), RFC 7313 */
-  *buf++ = 0;
-  *buf++ = BGP_AF;
-  *buf++ = BGP_RR_BEGIN;
-  *buf++ = 1;		/* SAFI */
-  return buf;
+  if (s->channel->cf->next_hop_self)
+    return 0;
+
+  /* We need valid global gateway */
+  if ((ra->dest != RTD_ROUTER) || ipa_zero(ra->gw) || ipa_is_link_local(ra->gw))
+    return 0;
+
+  /* Use it when exported to internal peers */
+  if (p->is_interior)
+    return 1;
+
+  /* Use it when forwarded to single-hop BGP peer on on the same iface */
+  return p->neigh && (p->neigh->iface == ra->iface);
 }
 
-static inline byte *
-bgp_create_end_refresh(struct bgp_conn *conn, byte *buf)
+static void
+bgp_update_next_hop_ip(struct bgp_export_state *s, eattr *a, ea_list **to)
 {
-  struct bgp_proto *p = conn->bgp;
-  BGP_TRACE(D_PACKETS, "Sending END-OF-RR");
+  if (!a || !bgp_use_next_hop(s, a))
+  {
+    if (bgp_use_gateway(s))
+    {
+      ip_addr nh[1] = { s->route->attrs->gw };
+      bgp_set_attr_data(to, s->pool, BA_NEXT_HOP, 0, nh, 16);
+    }
+    else
+    {
+      ip_addr nh[2] = { s->channel->next_hop_addr, s->channel->link_addr };
+      bgp_set_attr_data(to, s->pool, BA_NEXT_HOP, 0, nh, ipa_nonzero(nh[1]) ? 32 : 16);
+    }
+  }
 
-  /* Demarcation of ending of route refresh (EoRR), RFC 7313 */
-  *buf++ = 0;
-  *buf++ = BGP_AF;
-  *buf++ = BGP_RR_END;
-  *buf++ = 1;		/* SAFI */
-  return buf;
+  /* Check if next hop is valid */
+  a = bgp_find_attr(*to, BA_NEXT_HOP);
+  if (!a)
+    WITHDRAW(NO_NEXT_HOP);
+
+  ip_addr *nh = (void *) a->u.ptr->data;
+  ip_addr peer = s->proto->cf->remote_ip;
+  uint len = a->u.ptr->length;
+
+  if (ipa_zero(nh[0]) && ((len != 32) || ipa_zero(nh[1])))
+    WITHDRAW(BAD_NEXT_HOP);
+
+  if (ipa_equal(peer, nh[0]) || ((len == 32) && ipa_equal(peer, nh[1])))
+    WITHDRAW(BAD_NEXT_HOP);
 }
 
 
+/*
+ *	UPDATE
+ */
+
 static void
-bgp_create_header(byte *buf, uint len, uint type)
+bgp_rte_update(struct bgp_parse_state *s, net_addr *n, u32 path_id, rta *a0)
 {
-  memset(buf, 0xff, 16);		/* Marker */
-  put_u16(buf+16, len);
-  buf[18] = type;
+  if (path_id != s->last_id)
+  {
+    s->last_src = rt_get_source(&s->proto->p, path_id);
+    s->last_id = path_id;
+
+    rta_free(s->cached_rta);
+    s->cached_rta = NULL;
+  }
+
+  if (!a0)
+  {
+    /* Route withdraw */
+    rte_update2(&s->channel->c, n, NULL, s->last_src);
+    return;
+  }
+
+  /* Prepare cached route attributes */
+  if (s->cached_rta == NULL)
+  {
+    a0->src = s->last_src;
+
+    /* Workaround for rta_lookup() breaking eattrs */
+    ea_list *ea = a0->eattrs;
+    s->cached_rta = rta_lookup(a0);
+    a0->eattrs = ea;
+  }
+
+  rta *a = rta_clone(s->cached_rta);
+  rte *e = rte_get_temp(a);
+
+  e->pflags = 0;
+  e->u.bgp.suppressed = 0;
+  rte_update2(&s->channel->c, n, e, s->last_src);
 }
 
-/**
- * bgp_fire_tx - transmit packets
- * @conn: connection
- *
- * Whenever the transmit buffers of the underlying TCP connection
- * are free and we have any packets queued for sending, the socket functions
- * call bgp_fire_tx() which takes care of selecting the highest priority packet
- * queued (Notification > Keepalive > Open > Update), assembling its header
- * and body and sending it to the connection.
- */
-static int
-bgp_fire_tx(struct bgp_conn *conn)
+
+
+static uint
+bgp_encode_nlri_ip4(struct bgp_write_state *s, struct bgp_bucket *buck, byte *buf, uint size)
 {
-  struct bgp_proto *p = conn->bgp;
-  uint s = conn->packets_to_send;
-  sock *sk = conn->sk;
-  byte *buf, *pkt, *end;
-  int type;
+  byte *pos = buf;
 
-  if (!sk)
-    {
-      conn->packets_to_send = 0;
-      return 0;
-    }
-  buf = sk->tbuf;
-  pkt = buf + BGP_HEADER_LENGTH;
+  while (!EMPTY_LIST(buck->prefixes) && (size >= (5 + sizeof(ip4_addr))))
+  {
+    struct bgp_prefix *px = HEAD(buck->prefixes);
+    struct net_addr_ip4 *net = (void *) px->net;
 
-  if (s & (1 << PKT_SCHEDULE_CLOSE))
-    {
-      /* We can finally close connection and enter idle state */
-      bgp_conn_enter_idle_state(conn);
-      return 0;
-    }
-  if (s & (1 << PKT_NOTIFICATION))
-    {
-      s = 1 << PKT_SCHEDULE_CLOSE;
-      type = PKT_NOTIFICATION;
-      end = bgp_create_notification(conn, pkt);
-    }
-  else if (s & (1 << PKT_KEEPALIVE))
+    /* Encode path ID */
+    if (s->add_path)
     {
-      s &= ~(1 << PKT_KEEPALIVE);
-      type = PKT_KEEPALIVE;
-      end = pkt;			/* Keepalives carry no data */
-      BGP_TRACE(D_PACKETS, "Sending KEEPALIVE");
-      bgp_start_timer(conn->keepalive_timer, conn->keepalive_time);
+      put_u32(pos, px->path_id);
+      ADVANCE(pos, size, 4);
     }
-  else if (s & (1 << PKT_OPEN))
+
+    ip4_addr a = ip4_hton(net->prefix);
+    uint b = (net->pxlen + 7) / 8;
+
+    /* Encode prefix length */
+    *pos = net->pxlen;
+    ADVANCE(pos, size, 1);
+
+    /* Encode prefix body */
+    memcpy(pos, &a, b);
+    ADVANCE(pos, size, b);
+
+    bgp_free_prefix(s->channel, px);
+  }
+
+  return pos - buf;
+}
+
+static void
+bgp_decode_nlri_ip4(struct bgp_parse_state *s, byte *pos, uint len, rta *a)
+{
+  while (len)
+  {
+    net_addr_ip4 net;
+    u32 path_id = 0;
+
+    /* Decode path ID */
+    if (s->add_path)
     {
-      s &= ~(1 << PKT_OPEN);
-      type = PKT_OPEN;
-      end = bgp_create_open(conn, pkt);
+      if (len < 5)
+	bgp_parse_error(s, 1);
+
+      path_id = get_u32(pos);
+      ADVANCE(pos, len, 4);
     }
-  else if (s & (1 << PKT_ROUTE_REFRESH))
+
+    /* Decode prefix length */
+    uint l = *pos;
+    uint b = (l + 7) / 8;
+    ADVANCE(pos, len, 1);
+
+    if (l > IP4_MAX_PREFIX_LENGTH)
+      bgp_parse_error(s, 10);
+
+    if (len < b)
+      bgp_parse_error(s, 1);
+
+    /* Decode prefix body */
+    ip4_addr addr = IP4_NONE;
+    memcpy(&addr, pos, b);
+    ADVANCE(pos, len, b);
+
+    net = NET_ADDR_IP4(ip4_ntoh(addr), l);
+    net_normalize_ip4(&net);
+
+    // XXXX validate prefix
+
+    bgp_rte_update(s, (net_addr *) &net, path_id, a);
+  }
+}
+
+static uint
+bgp_encode_next_hop_ip4(struct bgp_write_state *s UNUSED, eattr *a, byte *buf, uint size UNUSED)
+{
+  /* This function is used only for MP-BGP, see bgp_encode_next_hop() for IPv4 BGP */
+
+  ASSERT(a->u.ptr->length == sizeof(ip_addr));
+
+  put_ip4(buf, ipa_to_ip4( *(ip_addr *) a->u.ptr->data ));
+
+  return 4;
+}
+
+static void
+bgp_decode_next_hop_ip4(struct bgp_parse_state *s, byte *data, uint len, rta *a)
+{
+  if (len != 4)
+    bgp_parse_error(s, 9);
+
+  ip_addr nh = ipa_from_ip4(get_ip4(data));
+
+  // XXXX validate next hop
+
+  bgp_set_attr_data(&(a->eattrs), s->pool, BA_NEXT_HOP, 0, &nh, sizeof(nh));
+  bgp_apply_next_hop(s, a, nh, IPA_NONE);
+}
+
+
+static uint
+bgp_encode_nlri_ip6(struct bgp_write_state *s, struct bgp_bucket *buck, byte *buf, uint size)
+{
+  byte *pos = buf;
+
+  while (!EMPTY_LIST(buck->prefixes) && (size >= (5 + sizeof(ip6_addr))))
+  {
+    struct bgp_prefix *px = HEAD(buck->prefixes);
+    struct net_addr_ip6 *net = (void *) px->net;
+
+    /* Encode path ID */
+    if (s->add_path)
     {
-      s &= ~(1 << PKT_ROUTE_REFRESH);
-      type = PKT_ROUTE_REFRESH;
-      end = bgp_create_route_refresh(conn, pkt);
+      put_u32(pos, px->path_id);
+      ADVANCE(pos, size, 4);
     }
-  else if (s & (1 << PKT_BEGIN_REFRESH))
+
+    ip6_addr a = ip6_hton(net->prefix);
+    uint b = (net->pxlen + 7) / 8;
+
+    /* Encode prefix length */
+    *pos = net->pxlen;
+    ADVANCE(pos, size, 1);
+
+    /* Encode prefix body */
+    memcpy(pos, &a, b);
+    ADVANCE(pos, size, b);
+
+    bgp_free_prefix(s->channel, px);
+  }
+
+  return pos - buf;
+}
+
+static void
+bgp_decode_nlri_ip6(struct bgp_parse_state *s, byte *pos, uint len, rta *a)
+{
+  while (len)
+  {
+    net_addr_ip6 net;
+    u32 path_id = 0;
+
+    /* Decode path ID */
+    if (s->add_path)
     {
-      s &= ~(1 << PKT_BEGIN_REFRESH);
-      type = PKT_ROUTE_REFRESH;	/* BoRR is a subtype of RR */
-      end = bgp_create_begin_refresh(conn, pkt);
+      if (len < 5)
+	bgp_parse_error(s, 1);
+
+      path_id = get_u32(pos);
+      ADVANCE(pos, len, 4);
     }
-  else if (s & (1 << PKT_UPDATE))
-    {
-      type = PKT_UPDATE;
-      end = bgp_create_update(conn, pkt);
 
-      if (!end)
-        {
-	  /* No update to send, perhaps we need to send End-of-RIB or EoRR */
+    /* Decode prefix length */
+    uint l = *pos;
+    uint b = (l + 7) / 8;
+    ADVANCE(pos, len, 1);
 
-	  conn->packets_to_send = 0;
+    if (l > IP6_MAX_PREFIX_LENGTH)
+      bgp_parse_error(s, 10);
 
-	  if (p->feed_state == BFS_LOADED)
-	  {
-	    type = PKT_UPDATE;
-	    end = bgp_create_end_mark(conn, pkt);
-	  }
+    if (len < b)
+      bgp_parse_error(s, 1);
 
-	  else if (p->feed_state == BFS_REFRESHED)
-	  {
-	    type = PKT_ROUTE_REFRESH;
-	    end = bgp_create_end_refresh(conn, pkt);
-	  }
+    /* Decode prefix body */
+    ip6_addr addr = IP6_NONE;
+    memcpy(&addr, pos, b);
+    ADVANCE(pos, len, b);
 
-	  else /* Really nothing to send */
-	    return 0;
+    net = NET_ADDR_IP6(ip6_ntoh(addr), l);
+    net_normalize_ip6(&net);
 
-	  p->feed_state = BFS_NONE;
-	}
-    }
-  else
-    return 0;
+    // XXXX validate prefix
 
-  conn->packets_to_send = s;
-  bgp_create_header(buf, end - buf, type);
-  return sk_send(sk, end - buf);
+    bgp_rte_update(s, (net_addr *) &net, path_id, a);
+  }
 }
 
-/**
- * bgp_schedule_packet - schedule a packet for transmission
- * @conn: connection
- * @type: packet type
- *
- * Schedule a packet of type @type to be sent as soon as possible.
- */
-void
-bgp_schedule_packet(struct bgp_conn *conn, int type)
+static uint
+bgp_encode_next_hop_ip6(struct bgp_write_state *s UNUSED, eattr *a, byte *buf, uint size UNUSED)
 {
-  DBG("BGP: Scheduling packet type %d\n", type);
-  conn->packets_to_send |= 1 << type;
-  if (conn->sk && conn->sk->tpos == conn->sk->tbuf && !ev_active(conn->tx_ev))
-    ev_schedule(conn->tx_ev);
+  ip_addr *nh = (void *) a->u.ptr->data;
+  uint len = a->u.ptr->length;
+
+  ASSERT((len == 16) || (len == 32));
+
+  put_ip6(buf, ipa_to_ip6(nh[0]));
+
+  if (len == 32)
+    put_ip6(buf+16, ipa_to_ip6(nh[1]));
+
+  return len;
 }
 
-void
-bgp_kick_tx(void *vconn)
+static void
+bgp_decode_next_hop_ip6(struct bgp_parse_state *s, byte *data, uint len, rta *a)
 {
-  struct bgp_conn *conn = vconn;
+  struct adata *ad = lp_alloc_adata(s->pool, 32);
+  ip_addr *nh = (void *) ad->data;
 
-  DBG("BGP: kicking TX\n");
-  while (bgp_fire_tx(conn) > 0)
-    ;
+  if ((len != 16) && (len != 32))
+    bgp_parse_error(s, 9);
+
+  nh[0] = ipa_from_ip6(get_ip6(data));
+  nh[1] = (len == 32) ? ipa_from_ip6(get_ip6(data+16)) : IPA_NONE;
+
+  if (ip6_is_link_local(nh[0]))
+  {
+    nh[1] = nh[0];
+    nh[0] = IPA_NONE;
+  }
+
+  if (!ip6_is_link_local(nh[1]))
+    nh[1] = IPA_NONE;
+
+  if (ipa_zero(nh[1]))
+    ad->length = 16;
+
+  // XXXX validate next hop
+
+  bgp_set_attr_ptr(&(a->eattrs), s->pool, BA_NEXT_HOP, 0, ad);
+  bgp_apply_next_hop(s, a, nh[0], nh[1]);
 }
 
-void
-bgp_tx(sock *sk)
+
+static const struct bgp_af_desc bgp_af_table[] = {
+  {
+    .afi = BGP_AF_IPV4,
+    .net = NET_IP4,
+    .name = "ipv4",
+    .encode_nlri = bgp_encode_nlri_ip4,
+    .decode_nlri = bgp_decode_nlri_ip4,
+    .encode_next_hop = bgp_encode_next_hop_ip4,
+    .decode_next_hop = bgp_decode_next_hop_ip4,
+    .update_next_hop = bgp_update_next_hop_ip,
+  },
+  {
+    .afi = BGP_AF_IPV4_MC,
+    .net = NET_IP4,
+    .name = "ipv4-mc",
+    .encode_nlri = bgp_encode_nlri_ip4,
+    .decode_nlri = bgp_decode_nlri_ip4,
+    .encode_next_hop = bgp_encode_next_hop_ip4,
+    .decode_next_hop = bgp_decode_next_hop_ip4,
+    .update_next_hop = bgp_update_next_hop_ip,
+  },
+  {
+    .afi = BGP_AF_IPV6,
+    .net = NET_IP6,
+    .name = "ipv6",
+    .encode_nlri = bgp_encode_nlri_ip6,
+    .decode_nlri = bgp_decode_nlri_ip6,
+    .encode_next_hop = bgp_encode_next_hop_ip6,
+    .decode_next_hop = bgp_decode_next_hop_ip6,
+    .update_next_hop = bgp_update_next_hop_ip,
+  },
+  {
+    .afi = BGP_AF_IPV6_MC,
+    .net = NET_IP6,
+    .name = "ipv6-mc",
+    .encode_nlri = bgp_encode_nlri_ip6,
+    .decode_nlri = bgp_decode_nlri_ip6,
+    .encode_next_hop = bgp_encode_next_hop_ip6,
+    .decode_next_hop = bgp_decode_next_hop_ip6,
+    .update_next_hop = bgp_update_next_hop_ip,
+  },
+};
+
+const struct bgp_af_desc *
+bgp_get_af_desc(u32 afi)
 {
-  struct bgp_conn *conn = sk->data;
+  uint i;
+  for (i = 0; i < ARRAY_SIZE(bgp_af_table); i++)
+    if (bgp_af_table[i].afi == afi)
+      return &bgp_af_table[i];
 
-  DBG("BGP: TX hook\n");
-  while (bgp_fire_tx(conn) > 0)
-    ;
+  return NULL;
 }
 
-/* Capatibility negotiation as per RFC 2842 */
+static inline uint
+bgp_encode_nlri(struct bgp_write_state *s, struct bgp_bucket *buck, byte *buf, byte *end)
+{
+  return s->channel->desc->encode_nlri(s, buck, buf, end - buf);
+}
+
+static inline uint
+bgp_encode_next_hop(struct bgp_write_state *s, eattr *nh, byte *buf)
+{
+  return s->channel->desc->encode_next_hop(s, nh, buf, 255);
+}
 
 void
-bgp_parse_capabilities(struct bgp_conn *conn, byte *opt, int len)
+bgp_update_next_hop(struct bgp_export_state *s, eattr *a, ea_list **to)
 {
-  // struct bgp_proto *p = conn->bgp;
-  int i, cl;
+  s->channel->desc->update_next_hop(s, a, to);
+}
 
-  while (len > 0)
-    {
-      if (len < 2 || len < 2 + opt[1])
-	goto err;
+#define MAX_ATTRS_LENGTH (end-buf+BGP_HEADER_LENGTH - 1024)
 
-      cl = opt[1];
+static byte *
+bgp_create_ip_reach(struct bgp_write_state *s, struct bgp_bucket *buck, byte *buf, byte *end)
+{
+  /*
+   *	2 B	Withdrawn Routes Length (zero)
+   *	---	IPv4 Withdrawn Routes NLRI (unused)
+   *	2 B	Total Path Attribute Length
+   *	var	Path Attributes
+   *	var	IPv4 Network Layer Reachability Information
+   */
+
+  int lr, la;
+
+  la = bgp_encode_attrs(s, buck->eattrs, buf+4, buf + MAX_ATTRS_LENGTH);
+  if (la < 0)
+  {
+    /* Attribute list too long */
+    bgp_withdraw_bucket(s->channel, buck);
+    return NULL;
+  }
 
-      switch (opt[0])
-	{
-	case 2:	/* Route refresh capability, RFC 2918 */
-	  if (cl != 0)
-	    goto err;
-	  conn->peer_refresh_support = 1;
-	  break;
+  put_u16(buf+0, 0);
+  put_u16(buf+2, la);
 
-	case 6: /* Extended message length capability, draft */
-	  if (cl != 0)
-	    goto err;
-	  conn->peer_ext_messages_support = 1;
-	  break;
+  lr = bgp_encode_nlri(s, buck, buf+4+la, end);
 
-	case 64: /* Graceful restart capability, RFC 4724 */
-	  if (cl % 4 != 2)
-	    goto err;
-	  conn->peer_gr_aware = 1;
-	  conn->peer_gr_able = 0;
-	  conn->peer_gr_time = get_u16(opt + 2) & 0x0fff;
-	  conn->peer_gr_flags = opt[2] & 0xf0;
-	  conn->peer_gr_aflags = 0;
-	  for (i = 2; i < cl; i += 4)
-	    if (opt[2+i+0] == 0 && opt[2+i+1] == BGP_AF && opt[2+i+2] == 1) /* Match AFI/SAFI */
-	      {
-		conn->peer_gr_able = 1;
-		conn->peer_gr_aflags = opt[2+i+3];
-	      }
-	  break;
+  return buf+4+la+lr;
+}
 
-	case 65: /* AS4 capability, RFC 4893 */
-	  if (cl != 4)
-	    goto err;
-	  conn->peer_as4_support = 1;
-	  if (conn->bgp->cf->enable_as4)
-	    conn->advertised_as = get_u32(opt + 2);
-	  break;
+static byte *
+bgp_create_mp_reach(struct bgp_write_state *s, struct bgp_bucket *buck, byte *buf, byte *end)
+{
+  /*
+   *	2 B	IPv4 Withdrawn Routes Length (zero)
+   *	---	IPv4 Withdrawn Routes NLRI (unused)
+   *	2 B	Total Path Attribute Length
+   *	1 B	MP_REACH_NLRI hdr - Attribute Flags
+   *	1 B	MP_REACH_NLRI hdr - Attribute Type Code
+   *	2 B	MP_REACH_NLRI hdr - Length of Attribute Data
+   *	2 B	MP_REACH_NLRI data - Address Family Identifier
+   *	1 B	MP_REACH_NLRI data - Subsequent Address Family Identifier
+   *	1 B	MP_REACH_NLRI data - Length of Next Hop Network Address
+   *	var	MP_REACH_NLRI data - Network Address of Next Hop
+   *	1 B	MP_REACH_NLRI data - Reserved (zero)
+   *	var	MP_REACH_NLRI data - Network Layer Reachability Information
+   *	var	Rest of Path Attributes
+   *	---	IPv4 Network Layer Reachability Information (unused)
+   */
+
+  int lh, lr, la;	/* Lengths of next hop, NLRI and attributes */
+
+  /* Begin of MP_REACH_NLRI atribute */
+  buf[4] = BAF_OPTIONAL | BAF_EXT_LEN;
+  buf[5] = BA_MP_REACH_NLRI;
+  put_u16(buf+6, 0);		/* Will be fixed later */
+  put_af3(buf+8, s->channel->afi);
+  byte *pos = buf+11;
+
+  /* Encode attributes to temporary buffer */
+  byte *abuf = alloca(MAX_ATTRS_LENGTH);
+  la = bgp_encode_attrs(s, buck->eattrs, abuf, abuf + MAX_ATTRS_LENGTH);
+  if (la < 0)
+  {
+    /* Attribute list too long */
+    bgp_withdraw_bucket(s->channel, buck);
+    return NULL;
+  }
 
-	case 69: /* ADD-PATH capability, draft */
-	  if (cl % 4)
-	    goto err;
-	  for (i = 0; i < cl; i += 4)
-	    if (opt[2+i+0] == 0 && opt[2+i+1] == BGP_AF && opt[2+i+2] == 1) /* Match AFI/SAFI */
-	      conn->peer_add_path = opt[2+i+3];
-	  if (conn->peer_add_path > ADD_PATH_FULL)
-	    goto err;
-	  break;
+  /* Encode the next hop */
+  lh = bgp_encode_next_hop(s, s->mp_next_hop, pos+1);
+  *pos = lh;
+  pos += 1+lh;
 
-	case 70: /* Enhanced route refresh capability, RFC 7313 */
-	  if (cl != 0)
-	    goto err;
-	  conn->peer_enhanced_refresh_support = 1;
-	  break;
+  /* Reserved field */
+  *pos++ = 0;
 
-	  /* We can safely ignore all other capabilities */
-	}
-      len -= 2 + cl;
-      opt += 2 + cl;
-    }
-  return;
+  /* Encode the NLRI */
+  lr = bgp_encode_nlri(s, buck, pos, end - la);
+  pos += lr;
 
- err:
-  bgp_error(conn, 2, 0, NULL, 0);
-  return;
+  /* End of MP_REACH_NLRI atribute, update data length */
+  put_u16(buf+6, pos-buf-8);
+
+  /* Copy remaining attributes */
+  memcpy(pos, abuf, la);
+  pos += la;
+
+  /* Initial UPDATE fields */
+  put_u16(buf+0, 0);
+  put_u16(buf+2, pos-buf-4);
+
+  return pos;
 }
 
-static int
-bgp_parse_options(struct bgp_conn *conn, byte *opt, int len)
+#undef MAX_ATTRS_LENGTH
+
+static byte *
+bgp_create_ip_unreach(struct bgp_write_state *s, struct bgp_bucket *buck, byte *buf, byte *end)
 {
-  struct bgp_proto *p = conn->bgp;
-  int ol;
+  /*
+   *	2 B	Withdrawn Routes Length
+   *	var	IPv4 Withdrawn Routes NLRI
+   *	2 B	Total Path Attribute Length (zero)
+   *	---	Path Attributes (unused)
+   *	---	IPv4 Network Layer Reachability Information (unused)
+   */
 
-  while (len > 0)
-    {
-      if (len < 2 || len < 2 + opt[1])
-	{ bgp_error(conn, 2, 0, NULL, 0); return 0; }
-#ifdef LOCAL_DEBUG
-      {
-	int i;
-	DBG("\tOption %02x:", opt[0]);
-	for(i=0; i<opt[1]; i++)
-	  DBG(" %02x", opt[2+i]);
-	DBG("\n");
-      }
-#endif
+  uint len = bgp_encode_nlri(s, buck, buf+2, end);
 
-      ol = opt[1];
-      switch (opt[0])
-	{
-	case 2:
-	  if (conn->start_state == BSS_CONNECT_NOCAP)
-	    BGP_TRACE(D_PACKETS, "Ignoring received capabilities");
-	  else
-	    bgp_parse_capabilities(conn, opt + 2, ol);
-	  break;
+  put_u16(buf+0, len);
+  put_u16(buf+2+len, 0);
 
-	default:
-	  /*
-	   *  BGP specs don't tell us to send which option
-	   *  we didn't recognize, but it's common practice
-	   *  to do so. Also, capability negotiation with
-	   *  Cisco routers doesn't work without that.
-	   */
-	  bgp_error(conn, 2, 4, opt, ol);
-	  return 0;
-	}
-      len -= 2 + ol;
-      opt += 2 + ol;
-    }
-  return 0;
+  return buf+4+len;
 }
 
-static void
-bgp_rx_open(struct bgp_conn *conn, byte *pkt, uint len)
+static byte *
+bgp_create_mp_unreach(struct bgp_write_state *s, struct bgp_bucket *buck, byte *buf, byte *end)
 {
-  struct bgp_conn *other;
-  struct bgp_proto *p = conn->bgp;
-  unsigned hold;
-  u16 base_as;
-  u32 id;
+  /*
+   *	2 B	Withdrawn Routes Length (zero)
+   *	---	IPv4 Withdrawn Routes NLRI (unused)
+   *	2 B	Total Path Attribute Length
+   *	1 B	MP_UNREACH_NLRI hdr - Attribute Flags
+   *	1 B	MP_UNREACH_NLRI hdr - Attribute Type Code
+   *	2 B	MP_UNREACH_NLRI hdr - Length of Attribute Data
+   *	2 B	MP_UNREACH_NLRI data - Address Family Identifier
+   *	1 B	MP_UNREACH_NLRI data - Subsequent Address Family Identifier
+   *	var	MP_UNREACH_NLRI data - Network Layer Reachability Information
+   *	---	IPv4 Network Layer Reachability Information (unused)
+   */
+
+  uint len = bgp_encode_nlri(s, buck, buf+11, end);
 
-  /* Check state */
-  if (conn->state != BS_OPENSENT)
-    { bgp_error(conn, 5, fsm_err_subcode[conn->state], NULL, 0); return; }
+  put_u16(buf+0, 0);
+  put_u16(buf+2, 7+len);
 
-  /* Check message contents */
-  if (len < 29 || len != 29U + pkt[28])
-    { bgp_error(conn, 1, 2, pkt+16, 2); return; }
-  if (pkt[19] != BGP_VERSION)
-    { bgp_error(conn, 2, 1, pkt+19, 1); return; } /* RFC 1771 says 16 bits, draft-09 tells to use 8 */
-  conn->advertised_as = base_as = get_u16(pkt+20);
-  hold = get_u16(pkt+22);
-  id = get_u32(pkt+24);
-  BGP_TRACE(D_PACKETS, "Got OPEN(as=%d,hold=%d,id=%08x)", conn->advertised_as, hold, id);
+  /* Begin of MP_UNREACH_NLRI atribute */
+  buf[4] = BAF_OPTIONAL | BAF_EXT_LEN;
+  buf[5] = BA_MP_UNREACH_NLRI;
+  put_u16(buf+6, 3+len);
+  put_af3(buf+8, s->channel->afi);
 
-  if (bgp_parse_options(conn, pkt+29, pkt[28]))
-    return;
+  return buf+11+len;
+}
 
-  if (hold > 0 && hold < 3)
-    { bgp_error(conn, 2, 6, pkt+22, 2); return; }
+static byte *
+bgp_create_update(struct bgp_channel *c, byte *buf)
+{
+  struct bgp_proto *p = (void *) c->c.proto;
+  struct bgp_bucket *buck;
+  byte *end = buf + (bgp_max_packet_length(p->conn) - BGP_HEADER_LENGTH);
+  byte *res = NULL;
+
+  /* Initialize write state */
+  struct bgp_write_state s = {
+    .proto = p,
+    .channel = c,
+    .pool = bgp_linpool,
+    .as4_session = p->as4_session,
+    .add_path = c->add_path_tx,
+  };
+
+again:
+
+  /* Try unreachable bucket */
+  if ((buck = c->withdraw_bucket) && !EMPTY_LIST(buck->prefixes))
+  {
+    res = (c->afi == BGP_AF_IPV4) ?
+      bgp_create_ip_unreach(&s, buck, buf, end):
+      bgp_create_mp_unreach(&s, buck, buf, end);
 
-  /* RFC 6286 2.2 - router ID is nonzero and AS-wide unique */
-  if (!id || (p->is_internal && id == p->local_id))
-    { bgp_error(conn, 2, 3, pkt+24, -4); return; }
+    goto done;
+  }
 
-  if ((conn->advertised_as != base_as) && (base_as != AS_TRANS))
-    log(L_WARN "%s: Peer advertised inconsistent AS numbers", p->p.name);
+  /* Try reachable buckets */
+  if (!EMPTY_LIST(c->bucket_queue))
+  {
+    buck = HEAD(c->bucket_queue);
 
-  if (conn->advertised_as != p->remote_as)
+    /* Cleanup empty buckets */
+    if (EMPTY_LIST(buck->prefixes))
     {
-      if (conn->peer_as4_support)
-	{
-	  u32 val = htonl(conn->advertised_as);
-	  bgp_error(conn, 2, 2, (byte *) &val, 4);
-	}
-      else
-	bgp_error(conn, 2, 2, pkt+20, 2);
-
-      return;
+      bgp_free_bucket(c, buck);
+      goto again;
     }
 
-  /* Check the other connection */
-  other = (conn == &p->outgoing_conn) ? &p->incoming_conn : &p->outgoing_conn;
-  switch (other->state)
-    {
-    case BS_CONNECT:
-    case BS_ACTIVE:
-      /* Stop outgoing connection attempts */
-      bgp_conn_enter_idle_state(other);
-      break;
+    res = (c->afi == BGP_AF_IPV4) ?
+      bgp_create_ip_reach(&s, buck, buf, end):
+      bgp_create_mp_reach(&s, buck, buf, end);
 
-    case BS_IDLE:
-    case BS_OPENSENT:
-    case BS_CLOSE:
-      break;
+    if (EMPTY_LIST(buck->prefixes))
+      bgp_free_bucket(c, buck);
+    else
+      bgp_defer_bucket(c, buck);
 
-    case BS_OPENCONFIRM:
-      /*
-       * Description of collision detection rules in RFC 4271 is confusing and
-       * contradictory, but it is essentially:
-       *
-       * 1. Router with higher ID is dominant
-       * 2. If both have the same ID, router with higher ASN is dominant [RFC6286]
-       * 3. When both connections are in OpenConfirm state, one initiated by
-       *    the dominant router is kept.
-       *
-       * The first line in the expression below evaluates whether the neighbor
-       * is dominant, the second line whether the new connection was initiated
-       * by the neighbor. If both are true (or both are false), we keep the new
-       * connection, otherwise we keep the old one.
-       */
-      if (((p->local_id < id) || ((p->local_id == id) && (p->local_as < p->remote_as)))
-	  == (conn == &p->incoming_conn))
-        {
-	  /* Should close the other connection */
-	  BGP_TRACE(D_EVENTS, "Connection collision, giving up the other connection");
-	  bgp_error(other, 6, 7, NULL, 0);
-	  break;
-	}
-      /* Fall thru */
-    case BS_ESTABLISHED:
-      /* Should close this connection */
-      BGP_TRACE(D_EVENTS, "Connection collision, giving up this connection");
-      bgp_error(conn, 6, 7, NULL, 0);
-      return;
-    default:
-      bug("bgp_rx_open: Unknown state");
-    }
+    if (!res)
+      goto again;
 
-  /* Update our local variables */
-  conn->hold_time = MIN(hold, p->cf->hold_time);
-  conn->keepalive_time = p->cf->keepalive_time ? : conn->hold_time / 3;
-  p->remote_id = id;
-  p->as4_session = p->cf->enable_as4 && conn->peer_as4_support;
-  p->add_path_rx = (p->cf->add_path & ADD_PATH_RX) && (conn->peer_add_path & ADD_PATH_TX);
-  p->add_path_tx = (p->cf->add_path & ADD_PATH_TX) && (conn->peer_add_path & ADD_PATH_RX);
-  p->gr_ready = p->cf->gr_mode && conn->peer_gr_able;
-  p->ext_messages = p->cf->enable_extended_messages && conn->peer_ext_messages_support;
+    goto done;
+  }
 
-  if (p->add_path_tx)
-    p->p.accept_ra_types = RA_ANY;
+  /* No more prefixes to send */
+  return NULL;
 
-  DBG("BGP: Hold timer set to %d, keepalive to %d, AS to %d, ID to %x, AS4 session to %d\n", conn->hold_time, conn->keepalive_time, p->remote_as, p->remote_id, p->as4_session);
+done:
+  BGP_TRACE_RL(&rl_snd_update, D_PACKETS, "Sending UPDATE");
+  lp_flush(s.pool);
 
-  bgp_schedule_packet(conn, PKT_KEEPALIVE);
-  bgp_start_timer(conn->hold_timer, conn->hold_time);
-  bgp_conn_enter_openconfirm_state(conn);
+  return res;
 }
 
-
-static inline void
-bgp_rx_end_mark(struct bgp_proto *p)
+static byte *
+bgp_create_ip_end_mark(struct bgp_channel *c UNUSED, byte *buf)
 {
-  BGP_TRACE(D_PACKETS, "Got END-OF-RIB");
+  /* Empty update packet */
+  put_u32(buf, 0);
 
-  if (p->load_state == BFS_LOADING)
-    p->load_state = BFS_NONE;
+  return buf+4;
+}
 
-  if (p->p.gr_recovery)
-    proto_graceful_restart_unlock(&p->p);
+static byte *
+bgp_create_mp_end_mark(struct bgp_channel *c, byte *buf)
+{
+  put_u16(buf+0, 0);
+  put_u16(buf+2, 6);		/* length 4--9 */
+
+  /* Empty MP_UNREACH_NLRI atribute */
+  buf[4] = BAF_OPTIONAL;
+  buf[5] = BA_MP_UNREACH_NLRI;
+  buf[6] = 3;			/* Length 7--9 */
+  put_af3(buf+7, c->afi);
 
-  if (p->gr_active)
-    bgp_graceful_restart_done(p);
+  return buf+10;
 }
 
+static byte *
+bgp_create_end_mark(struct bgp_channel *c, byte *buf)
+{
+  struct bgp_proto *p = (void *) c->c.proto;
 
-#define DECODE_PREFIX(pp, ll) do {		\
-  if (p->add_path_rx)				\
-  {						\
-    if (ll < 5) { err=1; goto done; }		\
-    path_id = get_u32(pp);			\
-    pp += 4;					\
-    ll -= 4;					\
-  }						\
-  int b = *pp++;				\
-  int q;					\
-  ll--;						\
-  if (b > BITS_PER_IP_ADDRESS) { err=10; goto done; } \
-  q = (b+7) / 8;				\
-  if (ll < q) { err=1; goto done; }		\
-  memcpy(&prefix, pp, q);			\
-  pp += q;					\
-  ll -= q;					\
-  ipa_ntoh(prefix);				\
-  prefix = ipa_and(prefix, ipa_mkmask(b));	\
-  pxlen = b;					\
-} while (0)
+  BGP_TRACE(D_PACKETS, "Sending END-OF-RIB");
 
+  return (c->afi == BGP_AF_IPV4) ?
+    bgp_create_ip_end_mark(c, buf):
+    bgp_create_mp_end_mark(c, buf);
+}
 
 static inline void
-bgp_rte_update(struct bgp_proto *p, ip_addr prefix, int pxlen,
-	       u32 path_id, u32 *last_id, struct rte_src **src,
-	       rta *a0, rta **a)
+bgp_rx_end_mark(struct bgp_proto *p, u32 afi)
 {
-  if (path_id != *last_id)
-    {
-      *src = rt_get_source(&p->p, path_id);
-      *last_id = path_id;
+  struct bgp_channel *c = bgp_get_channel(p, afi);
 
-      if (*a)
-	{
-	  rta_free(*a);
-	  *a = NULL;
-	}
-    }
+  BGP_TRACE(D_PACKETS, "Got END-OF-RIB");
 
-  /* Prepare cached route attributes */
-  if (!*a)
-    {
-      a0->src = *src;
+  /* XXXX handle unknown AF in MP_*_NLRI */
+  if (!c)
+    return;
 
-      /* Workaround for rta_lookup() breaking eattrs */
-      ea_list *ea = a0->eattrs;
-      *a = rta_lookup(a0);
-      a0->eattrs = ea;
-    }
+  if (c->load_state == BFS_LOADING)
+    c->load_state = BFS_NONE;
 
-  net *n = net_get(p->p.table, prefix, pxlen);
-  rte *e = rte_get_temp(rta_clone(*a));
-  e->net = n;
-  e->pflags = 0;
-  e->u.bgp.suppressed = 0;
-  rte_update2(p->p.main_ahook, n, e, *src);
+  if (p->p.gr_recovery)
+    channel_graceful_restart_unlock(&c->c);
+
+  if (c->gr_active)
+    bgp_graceful_restart_done(c);
 }
 
 static inline void
-bgp_rte_withdraw(struct bgp_proto *p, ip_addr prefix, int pxlen,
-		 u32 path_id, u32 *last_id, struct rte_src **src)
+bgp_decode_nlri(struct bgp_parse_state *s, u32 afi, byte *nlri, uint len, ea_list *ea, byte *nh, uint nh_len)
 {
-  if (path_id != *last_id)
-    {
-      *src = rt_find_source(&p->p, path_id);
-      *last_id = path_id;
-    }
-
-  net *n = net_find(p->p.table, prefix, pxlen);
-  rte_update2( p->p.main_ahook, n, NULL, *src);
-}
+  struct bgp_channel *c = bgp_get_channel(s->proto, afi);
+  rta *a = NULL;
 
-static inline int
-bgp_set_next_hop(struct bgp_proto *p, rta *a)
-{
-  struct eattr *nh = ea_find(a->eattrs, EA_CODE(EAP_BGP, BA_NEXT_HOP));
-  ip_addr *nexthop = (ip_addr *) nh->u.ptr->data;
+  /* XXXX handle unknown AF in MP_*_NLRI */
+  if (!c)
+    return;
 
-#ifdef IPV6
-  int second = (nh->u.ptr->length == NEXT_HOP_LENGTH) && ipa_nonzero(nexthop[1]);
+  s->channel = c;
+  s->add_path = c->add_path_rx;
 
-  /* First address should not be link-local, but may be zero in direct mode */
-  if (ipa_is_link_local(*nexthop))
-    *nexthop = IPA_NONE;
-#else
-  int second = 0;
-#endif
+  s->last_id = 0;
+  s->last_src = s->proto->p.main_source;
 
-  if (p->cf->gw_mode == GW_DIRECT)
-    {
-      neighbor *ng = NULL;
+  /*
+   * IPv4 BGP and MP-BGP may be used together in one update, therefore we do not
+   * add BA_NEXT_HOP in bgp_decode_attrs(), but we add it here independently for
+   * IPv4 BGP and MP-BGP. We undo the attribute (and possibly others attached by
+   * decode_next_hop hooks) by restoring a->eattrs afterwards.
+   */
 
-      if (ipa_nonzero(*nexthop))
-	ng = neigh_find(&p->p, nexthop, 0);
-      else if (second)	/* GW_DIRECT -> single_hop -> p->neigh != NULL */
-	ng = neigh_find2(&p->p, nexthop + 1, p->neigh->iface, 0);
+  if (ea)
+  {
+    a = alloca(sizeof(struct rta));
+    memset(a, 0, sizeof(struct rta));
 
-      /* Fallback */
-      if (!ng)
-	ng = p->neigh;
+    a->source = RTS_BGP;
+    a->scope = SCOPE_UNIVERSE;
+    a->cast = RTC_UNICAST;
+    a->dest = RTD_UNREACHABLE;
+    a->from = s->proto->cf->remote_ip;
+    a->eattrs = ea;
 
-      if (ng->scope == SCOPE_HOST)
-	return 0;
+    c->desc->decode_next_hop(s, nh, nh_len, a);
 
-      a->dest = RTD_ROUTER;
-      a->gw = ng->addr;
-      a->iface = ng->iface;
-      a->hostentry = NULL;
-      a->igp_metric = 0;
-    }
-  else /* GW_RECURSIVE */
-    {
-      if (ipa_zero(*nexthop))
-	  return 0;
+    /* Handle withdraw during next hop decoding */
+    if (s->err_withdraw)
+      a = NULL;
+  }
 
-      rta_set_recursive_next_hop(p->p.table, a, p->igp_table, nexthop, nexthop + second);
-    }
+  c->desc->decode_nlri(s, nlri, len, a);
 
-  return 1;
+  rta_free(s->cached_rta);
+  s->cached_rta = NULL;
 }
 
-#ifndef IPV6		/* IPv4 version */
-
 static void
-bgp_do_rx_update(struct bgp_conn *conn,
-		 byte *withdrawn, int withdrawn_len,
-		 byte *nlri, int nlri_len,
-		 byte *attrs, int attr_len)
+bgp_rx_update(struct bgp_conn *conn, byte *pkt, uint len)
 {
   struct bgp_proto *p = conn->bgp;
-  struct rte_src *src = p->p.main_source;
-  rta *a0, *a = NULL;
-  ip_addr prefix;
-  int pxlen, err = 0;
-  u32 path_id = 0;
-  u32 last_id = 0;
+  ea_list *ea = NULL;
 
-  /* Check for End-of-RIB marker */
-  if (!withdrawn_len && !attr_len && !nlri_len)
-    {
-      bgp_rx_end_mark(p);
-      return;
-    }
+  BGP_TRACE_RL(&rl_rcv_update, D_PACKETS, "Got UPDATE");
 
-  /* Withdraw routes */
-  while (withdrawn_len)
-    {
-      DECODE_PREFIX(withdrawn, withdrawn_len);
-      DBG("Withdraw %I/%d\n", prefix, pxlen);
+  /* Workaround for some BGP implementations that skip initial KEEPALIVE */
+  if (conn->state == BS_OPENCONFIRM)
+    bgp_conn_enter_established_state(conn);
 
-      bgp_rte_withdraw(p, prefix, pxlen, path_id, &last_id, &src);
-    }
+  if (conn->state != BS_ESTABLISHED)
+  { bgp_error(conn, 5, fsm_err_subcode[conn->state], NULL, 0); return; }
 
-  if (!attr_len && !nlri_len)		/* shortcut */
-    return;
+  bgp_start_timer(conn->hold_timer, conn->hold_time);
 
-  a0 = bgp_decode_attrs(conn, attrs, attr_len, bgp_linpool, nlri_len);
+  /* Initialize parse state */
+  struct bgp_parse_state s = {
+    .proto = p,
+    .pool = bgp_linpool,
+    .as4_session = p->as4_session,
+  };
 
-  if (conn->state != BS_ESTABLISHED)	/* fatal error during decoding */
-    return;
+  /* Parse error handler */
+  if (setjmp(s.err_jmpbuf))
+  {
+    bgp_error(conn, 3, s.err_subcode, NULL, 0);
+    goto done;
+  }
 
-  if (a0 && nlri_len && !bgp_set_next_hop(p, a0))
-    a0 = NULL;
+  /* Check minimal length */
+  if (len < 23)
+  { bgp_error(conn, 1, 2, pkt+16, 2); return; }
 
-  last_id = 0;
-  src = p->p.main_source;
+  /* Skip fixed header */
+  uint pos = 19;
 
-  while (nlri_len)
-    {
-      DECODE_PREFIX(nlri, nlri_len);
-      DBG("Add %I/%d\n", prefix, pxlen);
+  /*
+   *	UPDATE message format
+   *
+   *	2 B	IPv4 Withdrawn Routes Length
+   *	var	IPv4 Withdrawn Routes NLRI
+   *	2 B	Total Path Attribute Length
+   *	var	Path Attributes
+   *	var	IPv4 Reachable Routes NLRI
+   */
 
-      if (a0)
-	bgp_rte_update(p, prefix, pxlen, path_id, &last_id, &src, a0, &a);
-      else /* Forced withdraw as a result of soft error */
-	bgp_rte_withdraw(p, prefix, pxlen, path_id, &last_id, &src);
-    }
+  s.ip_unreach_len = get_u16(pkt + pos);
+  s.ip_unreach_nlri = pkt + pos + 2;
+  pos += 2 + s.ip_unreach_len;
 
- done:
-  if (a)
-    rta_free(a);
+  if (pos + 2 > len)
+    bgp_parse_error(&s, 1);
 
-  if (err)
-    bgp_error(conn, 3, err, NULL, 0);
+  s.attr_len = get_u16(pkt + pos);
+  s.attrs = pkt + pos + 2;
+  pos += 2 + s.attr_len;
+
+  if (pos > len)
+    bgp_parse_error(&s, 1);
+
+  s.ip_reach_len = len - pos;
+  s.ip_reach_nlri = pkt + pos;
+
+
+  if (s.attr_len)
+    ea = bgp_decode_attrs(&s, s.attrs, s.attr_len);
+
+  /* Check for End-of-RIB marker */
+  if (!s.attr_len && !s.ip_unreach_len && !s.ip_reach_len)
+  { bgp_rx_end_mark(p, BGP_AF_IPV4); goto done; }
+
+  /* Check for MP End-of-RIB marker */
+  if ((s.attr_len < 8) && !s.ip_unreach_len && !s.ip_reach_len &&
+      !s.mp_reach_len && !s.mp_unreach_len && s.mp_unreach_af) /* XXXX  See RFC 7606 5.2 */
+  { bgp_rx_end_mark(p, s.mp_unreach_af); goto done; }
+
+  if (s.ip_unreach_len)
+    bgp_decode_nlri(&s, BGP_AF_IPV4, s.ip_unreach_nlri, s.ip_unreach_len, NULL, NULL, 0);
+
+  if (s.mp_unreach_len)
+    bgp_decode_nlri(&s, s.mp_unreach_af, s.mp_unreach_nlri, s.mp_unreach_len, NULL, NULL, 0);
 
+  if (s.ip_reach_len)
+    bgp_decode_nlri(&s, BGP_AF_IPV4, s.ip_reach_nlri, s.ip_reach_len,
+		    ea, s.ip_next_hop_data, s.ip_next_hop_len);
+
+  if (s.mp_reach_len)
+    bgp_decode_nlri(&s, s.mp_reach_af, s.mp_reach_nlri, s.mp_reach_len,
+		    ea, s.mp_next_hop_data, s.mp_next_hop_len);
+
+done:
+  rta_free(s.cached_rta);
+  lp_flush(s.pool);
   return;
 }
 
-#else			/* IPv6 version */
-
-#define DO_NLRI(name)					\
-  x = p->name##_start;				\
-  len = len0 = p->name##_len;				\
-  if (len)						\
-    {							\
-      if (len < 3) { err=9; goto done; }		\
-      af = get_u16(x);					\
-      x += 3;						\
-      len -= 3;						\
-      DBG("\tNLRI AF=%d sub=%d len=%d\n", af, x[-1], len);\
-    }							\
-  else							\
-    af = 0;						\
-  if (af == BGP_AF_IPV6)
 
-static void
-bgp_attach_next_hop(rta *a0, byte *x)
+/*
+ *	ROUTE-REFRESH
+ */
+
+static inline byte *
+bgp_create_route_refresh(struct bgp_channel *c, byte *buf)
 {
-  ip_addr *nh = (ip_addr *) bgp_attach_attr_wa(&a0->eattrs, bgp_linpool, BA_NEXT_HOP, NEXT_HOP_LENGTH);
-  memcpy(nh, x+1, 16);
-  ipa_ntoh(nh[0]);
+  struct bgp_proto *p = (void *) c->c.proto;
 
-  /* We store received link local address in the other part of BA_NEXT_HOP eattr. */
-  if (*x == 32)
-    {
-      memcpy(nh+1, x+17, 16);
-      ipa_ntoh(nh[1]);
-    }
-  else
-    nh[1] = IPA_NONE;
+  BGP_TRACE(D_PACKETS, "Sending ROUTE-REFRESH");
+
+  /* Original route refresh request, RFC 2918 */
+  put_af4(buf, c->afi);
+  buf[2] = BGP_RR_REQUEST;
+
+  return buf+4;
 }
 
+static inline byte *
+bgp_create_begin_refresh(struct bgp_channel *c, byte *buf)
+{
+  struct bgp_proto *p = (void *) c->c.proto;
+
+  BGP_TRACE(D_PACKETS, "Sending BEGIN-OF-RR");
+
+  /* Demarcation of beginning of route refresh (BoRR), RFC 7313 */
+  put_af4(buf, c->afi);
+  buf[2] = BGP_RR_BEGIN;
+
+  return buf+4;
+}
+
+static inline byte *
+bgp_create_end_refresh(struct bgp_channel *c, byte *buf)
+{
+  struct bgp_proto *p = (void *) c->c.proto;
+
+  BGP_TRACE(D_PACKETS, "Sending END-OF-RR");
+
+  /* Demarcation of ending of route refresh (EoRR), RFC 7313 */
+  put_af4(buf, c->afi);
+  buf[2] = BGP_RR_END;
+
+  return buf+4;
+}
 
 static void
-bgp_do_rx_update(struct bgp_conn *conn,
-		 byte *withdrawn UNUSED, int withdrawn_len,
-		 byte *nlri UNUSED, int nlri_len,
-		 byte *attrs, int attr_len)
+bgp_rx_route_refresh(struct bgp_conn *conn, byte *pkt, uint len)
 {
   struct bgp_proto *p = conn->bgp;
-  struct rte_src *src = p->p.main_source;
-  byte *x;
-  int len, len0;
-  unsigned af;
-  rta *a0, *a = NULL;
-  ip_addr prefix;
-  int pxlen, err = 0;
-  u32 path_id = 0;
-  u32 last_id = 0;
-
-  p->mp_reach_len = 0;
-  p->mp_unreach_len = 0;
-  a0 = bgp_decode_attrs(conn, attrs, attr_len, bgp_linpool, 0);
-
-  if (conn->state != BS_ESTABLISHED)	/* fatal error during decoding */
-    return;
 
-  /* Check for End-of-RIB marker */
-  if ((attr_len < 8) && !withdrawn_len && !nlri_len && !p->mp_reach_len &&
-      (p->mp_unreach_len == 3) && (get_u16(p->mp_unreach_start) == BGP_AF_IPV6))
-    {
-      bgp_rx_end_mark(p);
-      return;
-    }
+  if (conn->state != BS_ESTABLISHED)
+  { bgp_error(conn, 5, fsm_err_subcode[conn->state], NULL, 0); return; }
 
-  DO_NLRI(mp_unreach)
-    {
-      while (len)
-	{
-	  DECODE_PREFIX(x, len);
-	  DBG("Withdraw %I/%d\n", prefix, pxlen);
-	  bgp_rte_withdraw(p, prefix, pxlen, path_id, &last_id, &src);
-	}
-    }
+  if (!conn->local_caps->route_refresh)
+  { bgp_error(conn, 1, 3, pkt+18, 1); return; }
 
-  DO_NLRI(mp_reach)
-    {
-      /* Create fake NEXT_HOP attribute */
-      if (len < 1 || (*x != 16 && *x != 32) || len < *x + 2)
-	{ err = 9; goto done; }
+  if (len < (BGP_HEADER_LENGTH + 4))
+  { bgp_error(conn, 1, 2, pkt+16, 2); return; }
 
-      if (a0)
-	bgp_attach_next_hop(a0, x);
+  if (len > (BGP_HEADER_LENGTH + 4))
+  { bgp_error(conn, 7, 1, pkt, MIN(len, 2048)); return; }
 
-      /* Also ignore one reserved byte */
-      len -= *x + 2;
-      x += *x + 2;
+  struct bgp_channel *c = bgp_get_channel(p, get_af4(pkt+19));
+  if (!c)
+  {
+    log(L_WARN "%s: Got ROUTE-REFRESH subtype %u for AF %u.%u, ignoring",
+	p->p.name, pkt[21], get_u16(pkt+19), pkt[22]);
+    return;
+  }
 
-      if (a0 && ! bgp_set_next_hop(p, a0))
-	a0 = NULL;
+  /* RFC 7313 redefined reserved field as RR message subtype */
+  uint subtype = p->enhanced_refresh ? pkt[21] : BGP_RR_REQUEST;
 
-      last_id = 0;
-      src = p->p.main_source;
+  switch (subtype)
+  {
+  case BGP_RR_REQUEST:
+    BGP_TRACE(D_PACKETS, "Got ROUTE-REFRESH");
+    channel_request_feeding(&c->c);
+    break;
 
-      while (len)
-	{
-	  DECODE_PREFIX(x, len);
-	  DBG("Add %I/%d\n", prefix, pxlen);
+  case BGP_RR_BEGIN:
+    BGP_TRACE(D_PACKETS, "Got BEGIN-OF-RR");
+    bgp_refresh_begin(c);
+    break;
 
-	  if (a0)
-	    bgp_rte_update(p, prefix, pxlen, path_id, &last_id, &src, a0, &a);
-	  else /* Forced withdraw as a result of soft error */
-	    bgp_rte_withdraw(p, prefix, pxlen, path_id, &last_id, &src);
-	}
-    }
+  case BGP_RR_END:
+    BGP_TRACE(D_PACKETS, "Got END-OF-RR");
+    bgp_refresh_end(c);
+    break;
 
- done:
-  if (a)
-    rta_free(a);
+  default:
+    log(L_WARN "%s: Got ROUTE-REFRESH message with unknown subtype %u, ignoring",
+	p->p.name, subtype);
+    break;
+  }
+}
+
+static inline struct bgp_channel *
+bgp_get_channel_to_send(struct bgp_proto *p, struct bgp_conn *conn)
+{
+  uint i = conn->last_channel;
 
-  if (err) /* Use subcode 9, not err */
-    bgp_error(conn, 3, 9, NULL, 0);
+  /* Try the last channel, but at most several times */
+  if ((conn->channels_to_send & (1 << i)) &&
+      (conn->last_channel_count < 16))
+    goto found;
 
-  return;
+  /* Find channel with non-zero channels_to_send */
+  do
+  {
+    i++;
+    if (i >= p->channel_count)
+      i = 0;
+  }
+  while (! (conn->channels_to_send & (1 << i)));
+
+  /* Use that channel */
+  conn->last_channel = i;
+  conn->last_channel_count = 0;
+
+found:
+  conn->last_channel_count++;
+  return p->channel_map[i];
 }
 
-#endif
+static inline int
+bgp_send(struct bgp_conn *conn, uint type, uint len)
+{
+  sock *sk = conn->sk;
+  byte *buf = sk->tbuf;
 
-static void
-bgp_rx_update(struct bgp_conn *conn, byte *pkt, uint len)
+  memset(buf, 0xff, 16);		/* Marker */
+  put_u16(buf+16, len);
+  buf[18] = type;
+
+  return sk_send(sk, len);
+}
+
+/**
+ * bgp_fire_tx - transmit packets
+ * @conn: connection
+ *
+ * Whenever the transmit buffers of the underlying TCP connection
+ * are free and we have any packets queued for sending, the socket functions
+ * call bgp_fire_tx() which takes care of selecting the highest priority packet
+ * queued (Notification > Keepalive > Open > Update), assembling its header
+ * and body and sending it to the connection.
+ */
+static int
+bgp_fire_tx(struct bgp_conn *conn)
 {
   struct bgp_proto *p = conn->bgp;
-  byte *withdrawn, *attrs, *nlri;
-  uint withdrawn_len, attr_len, nlri_len;
+  struct bgp_channel *c;
+  byte *buf, *pkt, *end;
+  uint s;
 
-  BGP_TRACE_RL(&rl_rcv_update, D_PACKETS, "Got UPDATE");
+  if (!conn->sk)
+    return 0;
 
-  /* Workaround for some BGP implementations that skip initial KEEPALIVE */
-  if (conn->state == BS_OPENCONFIRM)
-    bgp_conn_enter_established_state(conn);
+  buf = conn->sk->tbuf;
+  pkt = buf + BGP_HEADER_LENGTH;
+  s = conn->packets_to_send;
 
-  if (conn->state != BS_ESTABLISHED)
-    { bgp_error(conn, 5, fsm_err_subcode[conn->state], NULL, 0); return; }
-  bgp_start_timer(conn->hold_timer, conn->hold_time);
+  if (s & (1 << PKT_SCHEDULE_CLOSE))
+  {
+    /* We can finally close connection and enter idle state */
+    bgp_conn_enter_idle_state(conn);
+    return 0;
+  }
+  if (s & (1 << PKT_NOTIFICATION))
+  {
+    conn->packets_to_send = 1 << PKT_SCHEDULE_CLOSE;
+    end = bgp_create_notification(conn, pkt);
+    return bgp_send(conn, PKT_NOTIFICATION, end - buf);
+  }
+  else if (s & (1 << PKT_KEEPALIVE))
+  {
+    conn->packets_to_send &= ~(1 << PKT_KEEPALIVE);
+    BGP_TRACE(D_PACKETS, "Sending KEEPALIVE");
+    bgp_start_timer(conn->keepalive_timer, conn->keepalive_time);
+    return bgp_send(conn, PKT_KEEPALIVE, BGP_HEADER_LENGTH);
+  }
+  else if (s & (1 << PKT_OPEN))
+  {
+    conn->packets_to_send &= ~(1 << PKT_OPEN);
+    end = bgp_create_open(conn, pkt);
+    return bgp_send(conn, PKT_OPEN, end - buf);
+  }
+  else while (conn->channels_to_send)
+  {
+    c = bgp_get_channel_to_send(p, conn);
+    s = c->packets_to_send;
 
-  /* Find parts of the packet and check sizes */
-  if (len < 23)
+    if (s & (1 << PKT_ROUTE_REFRESH))
     {
-      bgp_error(conn, 1, 2, pkt+16, 2);
-      return;
+      c->packets_to_send &= ~(1 << PKT_ROUTE_REFRESH);
+      end = bgp_create_route_refresh(c, pkt);
+      return bgp_send(conn, PKT_ROUTE_REFRESH, end - buf);
     }
-  withdrawn = pkt + 21;
-  withdrawn_len = get_u16(pkt + 19);
-  if (withdrawn_len + 23 > len)
-    goto malformed;
-  attrs = withdrawn + withdrawn_len + 2;
-  attr_len = get_u16(attrs - 2);
-  if (withdrawn_len + attr_len + 23 > len)
-    goto malformed;
-  nlri = attrs + attr_len;
-  nlri_len = len - withdrawn_len - attr_len - 23;
-  if (!attr_len && nlri_len)
-    goto malformed;
-  DBG("Sizes: withdrawn=%d, attrs=%d, NLRI=%d\n", withdrawn_len, attr_len, nlri_len);
-
-  lp_flush(bgp_linpool);
-
-  bgp_do_rx_update(conn, withdrawn, withdrawn_len, nlri, nlri_len, attrs, attr_len);
-  return;
+    else if (s & (1 << PKT_BEGIN_REFRESH))
+    {
+      /* BoRR is a subtype of RR, but uses separate bit in packets_to_send */
+      c->packets_to_send &= ~(1 << PKT_BEGIN_REFRESH);
+      end = bgp_create_begin_refresh(c, pkt);
+      return bgp_send(conn, PKT_ROUTE_REFRESH, end - buf);
+    }
+    else if (s & (1 << PKT_UPDATE))
+    {
+      end = bgp_create_update(c, pkt);
+      if (end)
+	return bgp_send(conn, PKT_UPDATE, end - buf);
+
+      /* No update to send, perhaps we need to send End-of-RIB or EoRR */
+      c->packets_to_send = 0;
+      conn->channels_to_send &= ~(1 << c->index);
+
+      if (c->feed_state == BFS_LOADED)
+      {
+	c->feed_state = BFS_NONE;
+	end = bgp_create_end_mark(c, pkt);
+	return bgp_send(conn, PKT_UPDATE, end - buf);
+      }
+
+      else if (c->feed_state == BFS_REFRESHED)
+      {
+	c->feed_state = BFS_NONE;
+	end = bgp_create_end_refresh(c, pkt);
+	return bgp_send(conn, PKT_ROUTE_REFRESH, end - buf);
+      }
+    }
+    else if (s)
+      bug("Channel packets_to_send: %x", s);
+
+    c->packets_to_send = 0;
+    conn->channels_to_send &= ~(1 << c->index);
+  }
+
+  return 0;
+}
+
+/**
+ * bgp_schedule_packet - schedule a packet for transmission
+ * @conn: connection
+ * @c: channel
+ * @type: packet type
+ *
+ * Schedule a packet of type @type to be sent as soon as possible.
+ */
+void
+bgp_schedule_packet(struct bgp_conn *conn, struct bgp_channel *c, int type)
+{
+  ASSERT(conn->sk);
+
+  DBG("BGP: Scheduling packet type %d\n", type);
+
+  if (c)
+  {
+    if (! conn->channels_to_send)
+    {
+      conn->last_channel = c->index;
+      conn->last_channel_count = 0;
+    }
+
+    c->packets_to_send |= 1 << type;
+    conn->channels_to_send |= 1 << c->index;
+  }
+  else
+    conn->packets_to_send |= 1 << type;
+
+  if ((conn->sk->tpos == conn->sk->tbuf) && !ev_active(conn->tx_ev))
+    ev_schedule(conn->tx_ev);
+}
+
+void
+bgp_kick_tx(void *vconn)
+{
+  struct bgp_conn *conn = vconn;
+
+  DBG("BGP: kicking TX\n");
+  while (bgp_fire_tx(conn) > 0)
+    ;
+}
+
+void
+bgp_tx(sock *sk)
+{
+  struct bgp_conn *conn = sk->data;
 
-malformed:
-  bgp_error(conn, 3, 1, NULL, 0);
+  DBG("BGP: TX hook\n");
+  while (bgp_fire_tx(conn) > 0)
+    ;
 }
 
+
 static struct {
   byte major, minor;
   byte *msg;
@@ -1475,26 +1906,25 @@ static struct {
  * which might be static string or given temporary buffer.
  */
 const char *
-bgp_error_dsc(unsigned code, unsigned subcode)
+bgp_error_dsc(uint code, uint subcode)
 {
   static char buff[32];
-  unsigned i;
+  uint i;
+
   for (i=0; i < ARRAY_SIZE(bgp_msg_table); i++)
     if (bgp_msg_table[i].major == code && bgp_msg_table[i].minor == subcode)
-      {
-	return bgp_msg_table[i].msg;
-      }
+      return bgp_msg_table[i].msg;
 
-  bsprintf(buff, "Unknown error %d.%d", code, subcode);
+  bsprintf(buff, "Unknown error %u.%u", code, subcode);
   return buff;
 }
 
 void
-bgp_log_error(struct bgp_proto *p, u8 class, char *msg, unsigned code, unsigned subcode, byte *data, unsigned len)
+bgp_log_error(struct bgp_proto *p, u8 class, char *msg, uint code, uint subcode, byte *data, uint len)
 {
   const byte *name;
   byte *t, argbuf[36];
-  unsigned i;
+  uint i;
 
   /* Don't report Cease messages generated by myself */
   if (code == 6 && class == BE_BGP_TX)
@@ -1510,7 +1940,7 @@ bgp_log_error(struct bgp_proto *p, u8 class, char *msg, unsigned code, unsigned
       if ((code == 2) && (subcode == 2) && ((len == 2) || (len == 4)))
 	{
 	  /* Bad peer AS - we would like to print the AS */
-	  t += bsprintf(t, "%d", (len == 2) ? get_u16(data) : get_u32(data));
+	  t += bsprintf(t, "%u", (len == 2) ? get_u16(data) : get_u32(data));
 	  goto done;
 	}
       if (len > 16)
@@ -1527,47 +1957,25 @@ static void
 bgp_rx_notification(struct bgp_conn *conn, byte *pkt, uint len)
 {
   struct bgp_proto *p = conn->bgp;
+
   if (len < 21)
-    {
-      bgp_error(conn, 1, 2, pkt+16, 2);
-      return;
-    }
+  { bgp_error(conn, 1, 2, pkt+16, 2); return; }
 
-  unsigned code = pkt[19];
-  unsigned subcode = pkt[20];
+  uint code = pkt[19];
+  uint subcode = pkt[20];
   int err = (code != 6);
 
   bgp_log_error(p, BE_BGP_RX, "Received", code, subcode, pkt+21, len-21);
   bgp_store_error(p, conn, BE_BGP_RX, (code << 16) | subcode);
 
-#ifndef IPV6
-  if ((code == 2) && ((subcode == 4) || (subcode == 7))
-      /* Error related to capability:
-       * 4 - Peer does not support capabilities at all.
-       * 7 - Peer request some capability. Strange unless it is IPv6 only peer.
-       */
-      && (p->cf->capabilities == 2)
-      /* Capabilities are not explicitly enabled or disabled, therefore heuristic is used */
-      && (conn->start_state == BSS_CONNECT)
-      /* Failed connection attempt have used capabilities */
-      && (p->cf->remote_as <= 0xFFFF))
-      /* Not possible with disabled capabilities */
-    {
-      /* We try connect without capabilities */
-      log(L_WARN "%s: Capability related error received, retry with capabilities disabled", p->p.name);
-      p->start_state = BSS_CONNECT_NOCAP;
-      err = 0;
-    }
-#endif
-
   bgp_conn_enter_close_state(conn);
-  bgp_schedule_packet(conn, PKT_SCHEDULE_CLOSE);
+  bgp_schedule_packet(conn, NULL, PKT_SCHEDULE_CLOSE);
 
-  if (err) 
-    {
-      bgp_update_startup_delay(p);
-      bgp_stop(p, 0);
-    }
+  if (err)
+  {
+    bgp_update_startup_delay(p);
+    bgp_stop(p, 0);
+  }
 }
 
 static void
@@ -1577,64 +1985,12 @@ bgp_rx_keepalive(struct bgp_conn *conn)
 
   BGP_TRACE(D_PACKETS, "Got KEEPALIVE");
   bgp_start_timer(conn->hold_timer, conn->hold_time);
-  switch (conn->state)
-    {
-    case BS_OPENCONFIRM:
-      bgp_conn_enter_established_state(conn);
-      break;
-    case BS_ESTABLISHED:
-      break;
-    default:
-      bgp_error(conn, 5, fsm_err_subcode[conn->state], NULL, 0);
-    }
-}
 
-static void
-bgp_rx_route_refresh(struct bgp_conn *conn, byte *pkt, uint len)
-{
-  struct bgp_proto *p = conn->bgp;
+  if (conn->state == BS_OPENCONFIRM)
+  { bgp_conn_enter_established_state(conn); return; }
 
   if (conn->state != BS_ESTABLISHED)
-    { bgp_error(conn, 5, fsm_err_subcode[conn->state], NULL, 0); return; }
-
-  if (!p->cf->enable_refresh)
-    { bgp_error(conn, 1, 3, pkt+18, 1); return; }
-
-  if (len < (BGP_HEADER_LENGTH + 4))
-    { bgp_error(conn, 1, 2, pkt+16, 2); return; }
-
-  if (len > (BGP_HEADER_LENGTH + 4))
-    { bgp_error(conn, 7, 1, pkt, MIN(len, 2048)); return; }
-
-  /* FIXME - we ignore AFI/SAFI values, as we support
-     just one value and even an error code for an invalid
-     request is not defined */
-
-  /* RFC 7313 redefined reserved field as RR message subtype */
-  uint subtype = conn->peer_enhanced_refresh_support ? pkt[21] : BGP_RR_REQUEST;
-
-  switch (subtype)
-  {
-  case BGP_RR_REQUEST:
-    BGP_TRACE(D_PACKETS, "Got ROUTE-REFRESH");
-    proto_request_feeding(&p->p);
-    break;
-
-  case BGP_RR_BEGIN:
-    BGP_TRACE(D_PACKETS, "Got BEGIN-OF-RR");
-    bgp_refresh_begin(p);
-    break;
-
-  case BGP_RR_END:
-    BGP_TRACE(D_PACKETS, "Got END-OF-RR");
-    bgp_refresh_end(p);
-    break;
-
-  default:
-    log(L_WARN "%s: Got ROUTE-REFRESH message with unknown subtype %u, ignoring",
-	p->p.name, subtype);
-    break;
-  }
+    bgp_error(conn, 5, fsm_err_subcode[conn->state], NULL, 0);
 }
 
 
@@ -1648,7 +2004,7 @@ bgp_rx_route_refresh(struct bgp_conn *conn, byte *pkt, uint len)
  * packet handler according to the packet type.
  */
 static void
-bgp_rx_packet(struct bgp_conn *conn, byte *pkt, unsigned len)
+bgp_rx_packet(struct bgp_conn *conn, byte *pkt, uint len)
 {
   byte type = pkt[18];
 
@@ -1658,14 +2014,14 @@ bgp_rx_packet(struct bgp_conn *conn, byte *pkt, unsigned len)
     mrt_dump_bgp_packet(conn, pkt, len);
 
   switch (type)
-    {
-    case PKT_OPEN:		return bgp_rx_open(conn, pkt, len);
-    case PKT_UPDATE:		return bgp_rx_update(conn, pkt, len);
-    case PKT_NOTIFICATION:      return bgp_rx_notification(conn, pkt, len);
-    case PKT_KEEPALIVE:		return bgp_rx_keepalive(conn);
-    case PKT_ROUTE_REFRESH:	return bgp_rx_route_refresh(conn, pkt, len);
-    default:			bgp_error(conn, 1, 3, pkt+18, 1);
-    }
+  {
+  case PKT_OPEN:		return bgp_rx_open(conn, pkt, len);
+  case PKT_UPDATE:		return bgp_rx_update(conn, pkt, len);
+  case PKT_NOTIFICATION:	return bgp_rx_notification(conn, pkt, len);
+  case PKT_KEEPALIVE:		return bgp_rx_keepalive(conn);
+  case PKT_ROUTE_REFRESH:	return bgp_rx_route_refresh(conn, pkt, len);
+  default:			bgp_error(conn, 1, 3, pkt+18, 1);
+  }
 }
 
 /**
@@ -1682,10 +2038,9 @@ int
 bgp_rx(sock *sk, uint size)
 {
   struct bgp_conn *conn = sk->data;
-  struct bgp_proto *p = conn->bgp;
   byte *pkt_start = sk->rbuf;
   byte *end = pkt_start + size;
-  unsigned i, len;
+  uint i, len;
 
   DBG("BGP: RX hook: Got %d bytes\n", size);
   while (end >= pkt_start + BGP_HEADER_LENGTH)
@@ -1699,7 +2054,7 @@ bgp_rx(sock *sk, uint size)
 	    break;
 	  }
       len = get_u16(pkt_start+16);
-      if (len < BGP_HEADER_LENGTH || len > bgp_max_packet_length(p))
+      if ((len < BGP_HEADER_LENGTH) || (len > bgp_max_packet_length(conn)))
 	{
 	  bgp_error(conn, 1, 2, pkt_start+16, 2);
 	  break;
diff --git a/proto/static/static.c b/proto/static/static.c
index b5e717ca..fb547537 100644
--- a/proto/static/static.c
+++ b/proto/static/static.c
@@ -104,7 +104,7 @@ static_install(struct proto *p, struct static_route *r, struct iface *ifa)
     }
 
   if (r->dest == RTDX_RECURSIVE)
-    rta_set_recursive_next_hop(p->main_channel->table, &a, p_igp_table(p), &r->via, &r->via);
+    rta_set_recursive_next_hop(p->main_channel->table, &a, p_igp_table(p), r->via, IPA_NONE);
 
   /* We skip rta_lookup() here */