Merge branch 'oz-trie-table'

5 files changed, 104 insertions, 5 deletions

diff --git a/proto/bgp/attrs.c b/proto/bgp/attrs.c
index 15713b63..1f927cbd 100644
--- a/proto/bgp/attrs.c
+++ b/proto/bgp/attrs.c
@@ -1683,6 +1683,10 @@ bgp_preexport(struct proto *P, rte **new, struct linpool *pool UNUSED)
   if (src == NULL)
     return 0;
 
+  /* Reject flowspec that failed validation */
+  if ((e->attrs->dest == RTD_UNREACHABLE) && net_is_flow(e->net->n.addr))
+      return -1;
+
   /* IBGP route reflection, RFC 4456 */
   if (p->is_internal && src->is_internal && (p->local_as == src->local_as))
   {
diff --git a/proto/bgp/bgp.c b/proto/bgp/bgp.c
index b6f21bc6..619a816b 100644
--- a/proto/bgp/bgp.c
+++ b/proto/bgp/bgp.c
@@ -101,6 +101,7 @@
  * RFC 8203 - BGP Administrative Shutdown Communication
  * RFC 8212 - Default EBGP Route Propagation Behavior without Policies
  * RFC 8654 - Extended Message Support for BGP
+ * RFC 9117 - Revised Validation Procedure for BGP Flow Specifications
  * draft-ietf-idr-ext-opt-param-07
  * draft-uttaro-idr-bgp-persistence-04
  * draft-walton-bgp-hostname-capability-02
@@ -1740,6 +1741,9 @@ bgp_channel_init(struct channel *C, struct channel_config *CF)
 
   if (cf->igp_table_ip6)
     c->igp_table_ip6 = cf->igp_table_ip6->table;
+
+  if (cf->base_table)
+    c->base_table = cf->base_table->table;
 }
 
 static int
@@ -1755,6 +1759,12 @@ bgp_channel_start(struct channel *C)
   if (c->igp_table_ip6)
     rt_lock_table(c->igp_table_ip6);
 
+  if (c->base_table)
+  {
+    rt_lock_table(c->base_table);
+    rt_flowspec_link(c->base_table, c->c.table);
+  }
+
   c->pool = p->p.pool; // XXXX
   bgp_init_bucket_table(c);
   bgp_init_prefix_table(c);
@@ -1839,6 +1849,12 @@ bgp_channel_cleanup(struct channel *C)
   if (c->igp_table_ip6)
     rt_unlock_table(c->igp_table_ip6);
 
+  if (c->base_table)
+  {
+    rt_flowspec_unlink(c->base_table, c->c.table);
+    rt_unlock_table(c->base_table);
+  }
+
   c->index = 0;
 
   /* Cleanup rest of bgp_channel starting at pool field */
@@ -1886,6 +1902,25 @@ bgp_default_igp_table(struct bgp_config *cf, struct bgp_channel_config *cc, u32
   cf_error("Undefined IGP table");
 }
 
+static struct rtable_config *
+bgp_default_base_table(struct bgp_config *cf, struct bgp_channel_config *cc)
+{
+  /* Expected table type */
+  u32 type = (cc->afi == BGP_AF_FLOW4) ? NET_IP4 : NET_IP6;
+
+  /* First, try appropriate IP channel */
+  u32 afi2 = BGP_AF(BGP_AFI(cc->afi), BGP_SAFI_UNICAST);
+  struct bgp_channel_config *cc2 = bgp_find_channel_config(cf, afi2);
+  if (cc2 && (cc2->c.table->addr_type == type))
+    return cc2->c.table;
+
+  /* Last, try default table of given type */
+  struct rtable_config *tab = cf->c.global->def_tables[type];
+  if (tab)
+    return tab;
+
+  cf_error("Undefined base table");
+}
 
 void
 bgp_postconfig(struct proto_config *CF)
@@ -2030,6 +2065,14 @@ bgp_postconfig(struct proto_config *CF)
 	cf_error("Mismatched IGP table type");
     }
 
+    /* Default value of base table */
+    if ((BGP_SAFI(cc->afi) == BGP_SAFI_FLOW) && cc->validate && !cc->base_table)
+      cc->base_table = bgp_default_base_table(cf, cc);
+
+    if (cc->base_table && !cc->base_table->trie_used)
+      cf_error("Flowspec validation requires base table (%s) with trie",
+	       cc->base_table->name);
+
     if (cf->multihop && (cc->gw_mode == GW_DIRECT))
       cf_error("Multihop BGP cannot use direct gateway mode");
 
@@ -2098,7 +2141,7 @@ bgp_reconfigure(struct proto *P, struct proto_config *CF)
   return same;
 }
 
-#define IGP_TABLE(cf, sym) ((cf)->igp_table_##sym ? (cf)->igp_table_##sym ->table : NULL )
+#define TABLE(cf, NAME) ((cf)->NAME ? (cf)->NAME->table : NULL )
 
 static int
 bgp_channel_reconfigure(struct channel *C, struct channel_config *CC, int *import_changed, int *export_changed)
@@ -2109,6 +2152,7 @@ bgp_channel_reconfigure(struct channel *C, struct channel_config *CC, int *impor
   struct bgp_channel_config *old = c->cf;
 
   if ((new->secondary != old->secondary) ||
+      (new->validate != old->validate) ||
       (new->gr_able != old->gr_able) ||
       (new->llgr_able != old->llgr_able) ||
       (new->llgr_time != old->llgr_time) ||
@@ -2116,8 +2160,9 @@ bgp_channel_reconfigure(struct channel *C, struct channel_config *CC, int *impor
       (new->add_path != old->add_path) ||
       (new->import_table != old->import_table) ||
       (new->export_table != old->export_table) ||
-      (IGP_TABLE(new, ip4) != IGP_TABLE(old, ip4)) ||
-      (IGP_TABLE(new, ip6) != IGP_TABLE(old, ip6)))
+      (TABLE(new, igp_table_ip4) != TABLE(old, igp_table_ip4)) ||
+      (TABLE(new, igp_table_ip6) != TABLE(old, igp_table_ip6)) ||
+      (TABLE(new, base_table) != TABLE(old, base_table)))
     return 0;
 
   if (new->mandatory && !old->mandatory && (C->channel_state != CS_UP))
@@ -2531,6 +2576,9 @@ bgp_show_proto_info(struct proto *P)
 
       if (c->igp_table_ip6)
 	cli_msg(-1006, "    IGP IPv6 table: %s", c->igp_table_ip6->name);
+
+      if (c->base_table)
+	cli_msg(-1006, "    Base table:     %s", c->base_table->name);
     }
   }
 }
diff --git a/proto/bgp/bgp.h b/proto/bgp/bgp.h
index 08e751e7..4969c0b9 100644
--- a/proto/bgp/bgp.h
+++ b/proto/bgp/bgp.h
@@ -147,6 +147,7 @@ struct bgp_channel_config {
   u8 mandatory;				/* Channel is mandatory in capability negotiation */
   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 validate;				/* Validate Flowspec per RFC 8955 (6) */
   u8 gr_able;				/* Allow full graceful restart for the channel */
   u8 llgr_able;				/* Allow full long-lived GR for the channel */
   uint llgr_time;			/* Long-lived graceful restart stale time */
@@ -160,6 +161,7 @@ struct bgp_channel_config {
 
   struct rtable_config *igp_table_ip4;	/* Table for recursive IPv4 next hop lookups */
   struct rtable_config *igp_table_ip6;	/* Table for recursive IPv6 next hop lookups */
+  struct rtable_config *base_table;	/* Base table for Flowspec validation */
 };
 
 #define BGP_PT_INTERNAL		1
@@ -341,6 +343,7 @@ struct bgp_channel {
 
   rtable *igp_table_ip4;		/* Table for recursive IPv4 next hop lookups */
   rtable *igp_table_ip6;		/* Table for recursive IPv6 next hop lookups */
+  rtable *base_table;			/* Base table for Flowspec validation */
 
   /* Rest are zeroed when down */
   pool *pool;
@@ -451,6 +454,7 @@ struct bgp_parse_state {
   jmp_buf err_jmpbuf;
 
   struct hostentry *hostentry;
+  struct rtable *base_table;
   adata *mpls_labels;
 
   /* Cached state for bgp_rte_update() */
@@ -517,7 +521,7 @@ struct rte_source *bgp_get_source(struct bgp_proto *p, u32 path_id);
 static inline int
 rte_resolvable(rte *rt)
 {
-  return rt->attrs->dest == RTD_UNICAST;
+  return rt->attrs->dest != RTD_UNREACHABLE;
 }
 
 
diff --git a/proto/bgp/config.Y b/proto/bgp/config.Y
index 7cbc9985..241aa7c2 100644
--- a/proto/bgp/config.Y
+++ b/proto/bgp/config.Y
@@ -31,7 +31,7 @@ CF_KEYWORDS(BGP, LOCAL, NEIGHBOR, AS, HOLD, TIME, CONNECT, RETRY, KEEPALIVE,
 	STRICT, BIND, CONFEDERATION, MEMBER, MULTICAST, FLOW4, FLOW6, LONG,
 	LIVED, STALE, IMPORT, IBGP, EBGP, MANDATORY, INTERNAL, EXTERNAL, SETS,
 	DYNAMIC, RANGE, NAME, DIGITS, BGP_AIGP, AIGP, ORIGINATE, COST, ENFORCE,
-	FIRST, FREE)
+	FIRST, FREE, VALIDATE, BASE)
 
 %type <i> bgp_nh
 %type <i32> bgp_afi
@@ -256,6 +256,11 @@ bgp_channel_item:
  | GATEWAY DIRECT { BGP_CC->gw_mode = GW_DIRECT; }
  | GATEWAY RECURSIVE { BGP_CC->gw_mode = GW_RECURSIVE; }
  | SECONDARY bool { BGP_CC->secondary = $2; }
+ | VALIDATE bool {
+    BGP_CC->validate = $2;
+    if (BGP_SAFI(BGP_CC->afi) != BGP_SAFI_FLOW)
+      cf_error("Validate option limited to flowspec channels");
+   }
  | GRACEFUL RESTART bool { BGP_CC->gr_able = $3; }
  | LONG LIVED GRACEFUL RESTART bool { BGP_CC->llgr_able = $5; }
  | LONG LIVED STALE TIME expr { BGP_CC->llgr_time = $5; }
@@ -279,6 +284,16 @@ bgp_channel_item:
     else
       cf_error("Mismatched IGP table type");
    }
+ | BASE TABLE rtable {
+    if (BGP_SAFI(BGP_CC->afi) != BGP_SAFI_FLOW)
+      cf_error("Base table option limited to flowspec channels");
+
+    if (((BGP_CC->afi == BGP_AF_FLOW4) && ($3->addr_type == NET_IP4)) ||
+        ((BGP_CC->afi == BGP_AF_FLOW6) && ($3->addr_type == NET_IP6)))
+      BGP_CC->base_table = $3;
+    else
+      cf_error("Mismatched base table type");
+   }
  ;
 
 bgp_channel_opts:
diff --git a/proto/bgp/packets.c b/proto/bgp/packets.c
index 21052186..f13625e2 100644
--- a/proto/bgp/packets.c
+++ b/proto/bgp/packets.c
@@ -1018,6 +1018,23 @@ bgp_apply_mpls_labels(struct bgp_parse_state *s, rta *a, u32 *labels, uint lnum)
   }
 }
 
+static void
+bgp_apply_flow_validation(struct bgp_parse_state *s, const net_addr *n, rta *a)
+{
+  struct bgp_channel *c = s->channel;
+  int valid = rt_flowspec_check(c->base_table, c->c.table, n, a, s->proto->is_interior);
+  a->dest = valid ? RTD_NONE : RTD_UNREACHABLE;
+
+  /* Set rte.bgp.base_table later from this state variable */
+  s->base_table = c->base_table;
+
+  /* Invalidate cached rta if dest changes */
+  if (s->cached_rta && (s->cached_rta->dest != a->dest))
+  {
+    rta_free(s->cached_rta);
+    s->cached_rta = NULL;
+  }
+}
 
 static int
 bgp_match_src(struct bgp_export_state *s, int mode)
@@ -1383,6 +1400,7 @@ bgp_rte_update(struct bgp_parse_state *s, const net_addr *n, u32 path_id, rta *a
   e->pflags = 0;
   e->u.bgp.suppressed = 0;
   e->u.bgp.stale = -1;
+  e->u.bgp.base_table = s->base_table;
   rte_update3(&s->channel->c, n, e, s->last_src);
 }
 
@@ -1897,6 +1915,10 @@ bgp_decode_nlri_flow4(struct bgp_parse_state *s, byte *pos, uint len, rta *a)
     net_fill_flow4(n, px, pxlen, pos, flen);
     ADVANCE(pos, len, flen);
 
+    /* Apply validation procedure per RFC 8955 (6) */
+    if (a && s->channel->cf->validate)
+      bgp_apply_flow_validation(s, n, a);
+
     bgp_rte_update(s, n, path_id, a);
   }
 }
@@ -1985,6 +2007,10 @@ bgp_decode_nlri_flow6(struct bgp_parse_state *s, byte *pos, uint len, rta *a)
     net_fill_flow6(n, px, pxlen, pos, flen);
     ADVANCE(pos, len, flen);
 
+    /* Apply validation procedure per RFC 8955 (6) */
+    if (a && s->channel->cf->validate)
+      bgp_apply_flow_validation(s, n, a);
+
     bgp_rte_update(s, n, path_id, a);
   }
 }
@@ -2438,6 +2464,8 @@ bgp_decode_nlri(struct bgp_parse_state *s, u32 afi, byte *nlri, uint len, ea_lis
   s->last_id = 0;
   s->last_src = s->proto->p.main_source;
 
+  s->base_table = 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