Merge remote-tracking branch 'origin/soft-int'

1 files changed, 298 insertions, 363 deletions

diff --git a/proto/ospf/packet.c b/proto/ospf/packet.c
index 1240b05c..fb63e61c 100644
--- a/proto/ospf/packet.c
+++ b/proto/ospf/packet.c
@@ -2,6 +2,8 @@
  *	BIRD -- OSPF
  *
  *	(c) 1999--2005 Ondrej Filip <feela@network.cz>
+ *	(c) 2009--2014 Ondrej Zajicek <santiago@crfreenet.org>
+ *	(c) 2009--2014 CZ.NIC z.s.p.o.
  *
  *	Can be freely distributed and used under the terms of the GNU GPL.
  */
@@ -13,233 +15,195 @@
 void
 ospf_pkt_fill_hdr(struct ospf_iface *ifa, void *buf, u8 h_type)
 {
-  struct proto_ospf *po = ifa->oa->po;
+  struct ospf_proto *p = ifa->oa->po;
   struct ospf_packet *pkt;
 
   pkt = (struct ospf_packet *) buf;
 
-  pkt->version = OSPF_VERSION;
-
+  pkt->version = ospf_get_version(p);
   pkt->type = h_type;
-
-  pkt->routerid = htonl(po->router_id);
+  pkt->length = htons(ospf_pkt_maxsize(ifa));
+  pkt->routerid = htonl(p->router_id);
   pkt->areaid = htonl(ifa->oa->areaid);
-
-#ifdef OSPFv3
-  pkt->instance_id = ifa->instance_id;
-#endif
-
-#ifdef OSPFv2
-  pkt->autype = htons(ifa->autype);
-#endif
-
   pkt->checksum = 0;
+  pkt->instance_id = ifa->instance_id;
+  pkt->autype = ifa->autype;
 }
 
-unsigned
+uint
 ospf_pkt_maxsize(struct ospf_iface *ifa)
 {
-  unsigned headers = SIZE_OF_IP_HEADER;
+  uint headers = SIZE_OF_IP_HEADER;
 
-#ifdef OSPFv2
+  /* Relevant just for OSPFv2 */
   if (ifa->autype == OSPF_AUTH_CRYPT)
     headers += OSPF_AUTH_CRYPT_SIZE;
-#endif
 
   return ifa->tx_length - headers;
 }
 
-#ifdef OSPFv2
-
+/* We assume OSPFv2 in ospf_pkt_finalize() */
 static void
 ospf_pkt_finalize(struct ospf_iface *ifa, struct ospf_packet *pkt)
 {
   struct password_item *passwd = NULL;
-  void *tail;
-  struct MD5Context ctxt;
-  char password[OSPF_AUTH_CRYPT_SIZE];
+  union ospf_auth *auth = (void *) (pkt + 1);
+  uint plen = ntohs(pkt->length);
 
   pkt->checksum = 0;
-  pkt->autype = htons(ifa->autype);
-  bzero(&pkt->u, sizeof(union ospf_auth));
+  pkt->autype = ifa->autype;
+  bzero(auth, sizeof(union ospf_auth));
 
-  /* Compatibility note: pkt->u may contain anything if autype is
+  /* Compatibility note: auth may contain anything if autype is
      none, but nonzero values do not work with Mikrotik OSPF */
 
-  switch(ifa->autype)
+  switch (ifa->autype)
   {
-    case OSPF_AUTH_SIMPLE:
-      passwd = password_find(ifa->passwords, 1);
-      if (!passwd)
-      {
-        log( L_ERR "No suitable password found for authentication" );
-        return;
-      }
-      password_cpy(pkt->u.password, passwd->password, sizeof(union ospf_auth));
-    case OSPF_AUTH_NONE:
-      pkt->checksum = ipsum_calculate(pkt, sizeof(struct ospf_packet) -
-                                  sizeof(union ospf_auth), (pkt + 1),
-				  ntohs(pkt->length) -
-				  sizeof(struct ospf_packet), NULL);
-      break;
-    case OSPF_AUTH_CRYPT:
-      passwd = password_find(ifa->passwords, 0);
-      if (!passwd)
-      {
-        log( L_ERR "No suitable password found for authentication" );
-        return;
-      }
+  case OSPF_AUTH_SIMPLE:
+    passwd = password_find(ifa->passwords, 1);
+    if (!passwd)
+    {
+      log(L_ERR "No suitable password found for authentication");
+      return;
+    }
+    strncpy(auth->password, passwd->password, sizeof(auth->password));
 
-      /* Perhaps use random value to prevent replay attacks after
-	 reboot when system does not have independent RTC? */
-      if (!ifa->csn)
-	{
-	  ifa->csn = (u32) now;
-	  ifa->csn_use = now;
-	}
+  case OSPF_AUTH_NONE:
+    {
+      void *body = (void *) (auth + 1);
+      uint blen = plen - sizeof(struct ospf_packet) - sizeof(union ospf_auth);
+      pkt->checksum = ipsum_calculate(pkt, sizeof(struct ospf_packet), body, blen, NULL);
+    }
+    break;
 
-      /* We must have sufficient delay between sending a packet and increasing 
-	 CSN to prevent reordering of packets (in a network) with different CSNs */
-      if ((now - ifa->csn_use) > 1)
-	ifa->csn++;
+  case OSPF_AUTH_CRYPT:
+    passwd = password_find(ifa->passwords, 0);
+    if (!passwd)
+    {
+      log(L_ERR "No suitable password found for authentication");
+      return;
+    }
 
+    /* Perhaps use random value to prevent replay attacks after
+       reboot when system does not have independent RTC? */
+    if (!ifa->csn)
+    {
+      ifa->csn = (u32) now;
       ifa->csn_use = now;
+    }
+
+    /* We must have sufficient delay between sending a packet and increasing
+       CSN to prevent reordering of packets (in a network) with different CSNs */
+    if ((now - ifa->csn_use) > 1)
+      ifa->csn++;
 
-      pkt->u.md5.keyid = passwd->id;
-      pkt->u.md5.len = OSPF_AUTH_CRYPT_SIZE;
-      pkt->u.md5.zero = 0;
-      pkt->u.md5.csn = htonl(ifa->csn);
-      tail = ((void *)pkt) + ntohs(pkt->length);
-      MD5Init(&ctxt);
-      MD5Update(&ctxt, (char *) pkt, ntohs(pkt->length));
-      password_cpy(password, passwd->password, OSPF_AUTH_CRYPT_SIZE);
-      MD5Update(&ctxt, password, OSPF_AUTH_CRYPT_SIZE);
-      MD5Final(tail, &ctxt);
-      break;
-    default:
-      bug("Unknown authentication type");
+    ifa->csn_use = now;
+
+    auth->md5.zero = 0;
+    auth->md5.keyid = passwd->id;
+    auth->md5.len = OSPF_AUTH_CRYPT_SIZE;
+    auth->md5.csn = htonl(ifa->csn);
+
+    void *tail = ((void *) pkt) + plen;
+    char password[OSPF_AUTH_CRYPT_SIZE];
+    strncpy(password, passwd->password, sizeof(password));
+
+    struct MD5Context ctxt;
+    MD5Init(&ctxt);
+    MD5Update(&ctxt, (char *) pkt, plen);
+    MD5Update(&ctxt, password, OSPF_AUTH_CRYPT_SIZE);
+    MD5Final(tail, &ctxt);
+    break;
+
+  default:
+    bug("Unknown authentication type");
   }
 }
 
+
+/* We assume OSPFv2 in ospf_pkt_checkauth() */
 static int
-ospf_pkt_checkauth(struct ospf_neighbor *n, struct ospf_iface *ifa, struct ospf_packet *pkt, int size)
+ospf_pkt_checkauth(struct ospf_neighbor *n, struct ospf_iface *ifa, struct ospf_packet *pkt, int len)
 {
-  struct proto_ospf *po = ifa->oa->po;
-  struct proto *p = &po->proto;
-  struct password_item *pass = NULL, *ptmp;
-  void *tail;
-  char md5sum[OSPF_AUTH_CRYPT_SIZE];
-  char password[OSPF_AUTH_CRYPT_SIZE];
-  struct MD5Context ctxt;
+  struct ospf_proto *p = ifa->oa->po;
+  union ospf_auth *auth = (void *) (pkt + 1);
+  struct password_item *pass = NULL;
+  const char *err_dsc = NULL;
+  uint err_val = 0;
 
+  uint plen = ntohs(pkt->length);
+  u8 autype = pkt->autype;
 
-  if (pkt->autype != htons(ifa->autype))
-  {
-    OSPF_TRACE(D_PACKETS, "OSPF_auth: Method differs (%d)", ntohs(pkt->autype));
-    return 0;
-  }
+  if (autype != ifa->autype)
+    DROP("authentication method mismatch", autype);
 
-  switch(ifa->autype)
+  switch (autype)
   {
-    case OSPF_AUTH_NONE:
-      return 1;
-      break;
-    case OSPF_AUTH_SIMPLE:
-      pass = password_find(ifa->passwords, 1);
-      if (!pass)
-      {
-        OSPF_TRACE(D_PACKETS, "OSPF_auth: no password found");
-	return 0;
-      }
-      password_cpy(password, pass->password, sizeof(union ospf_auth));
-
-      if (memcmp(pkt->u.password, password, sizeof(union ospf_auth)))
-      {
-        char ppass[sizeof(union ospf_auth) + 1];
-        bzero(ppass, (sizeof(union ospf_auth) + 1));
-        memcpy(ppass, pkt->u.password, sizeof(union ospf_auth));
-        OSPF_TRACE(D_PACKETS, "OSPF_auth: different passwords (%s)", ppass);
-	return 0;
-      }
-      return 1;
-      break;
-    case OSPF_AUTH_CRYPT:
-      if (pkt->u.md5.len != OSPF_AUTH_CRYPT_SIZE)
-      {
-        OSPF_TRACE(D_PACKETS, "OSPF_auth: wrong size of md5 digest");
-        return 0;
-      }
+  case OSPF_AUTH_NONE:
+    return 1;
 
-      if (ntohs(pkt->length) + OSPF_AUTH_CRYPT_SIZE > size)
-      {
-        OSPF_TRACE(D_PACKETS, "OSPF_auth: size mismatch (%d vs %d)",
-	  ntohs(pkt->length) + OSPF_AUTH_CRYPT_SIZE, size);
-        return 0;
-      }
+  case OSPF_AUTH_SIMPLE:
+    pass = password_find(ifa->passwords, 1);
+    if (!pass)
+      DROP1("no password found");
 
-      tail = ((void *)pkt) + ntohs(pkt->length);
+    if (!password_verify(pass, auth->password, sizeof(auth->password)))
+      DROP("wrong password", pass->id);
 
-      if (ifa->passwords)
-      {
-	WALK_LIST(ptmp, *(ifa->passwords))
-	{
-	  if (pkt->u.md5.keyid != ptmp->id) continue;
-	  if ((ptmp->accfrom > now_real) || (ptmp->accto < now_real)) continue;
-	  pass = ptmp;
-	  break;
-	}
-      }
+    return 1;
 
-      if (!pass)
-      {
-        OSPF_TRACE(D_PACKETS, "OSPF_auth: no suitable md5 password found");
-        return 0;
-      }
+  case OSPF_AUTH_CRYPT:
+    if (auth->md5.len != OSPF_AUTH_CRYPT_SIZE)
+      DROP("invalid MD5 digest length", auth->md5.len);
 
-      if (n)
-      {
-	u32 rcv_csn = ntohl(pkt->u.md5.csn);
-	if(rcv_csn < n->csn)
-	{
-	  OSPF_TRACE(D_PACKETS, "OSPF_auth: lower sequence number (rcv %d, old %d)", rcv_csn, n->csn);
-	  return 0;
-	}
-
-	n->csn = rcv_csn;
-      }
+    if (plen + OSPF_AUTH_CRYPT_SIZE > len)
+      DROP("length mismatch", len);
 
-      MD5Init(&ctxt);
-      MD5Update(&ctxt, (char *) pkt, ntohs(pkt->length));
-      password_cpy(password, pass->password, OSPF_AUTH_CRYPT_SIZE);
-      MD5Update(&ctxt, password, OSPF_AUTH_CRYPT_SIZE);
-      MD5Final(md5sum, &ctxt);
-      if (memcmp(md5sum, tail, OSPF_AUTH_CRYPT_SIZE))
-      {
-        OSPF_TRACE(D_PACKETS, "OSPF_auth: wrong md5 digest");
-        return 0;
-      }
-      return 1;
-      break;
-    default:
-      OSPF_TRACE(D_PACKETS, "OSPF_auth: unknown auth type");
+    u32 rcv_csn = ntohl(auth->md5.csn);
+    if (n && (rcv_csn < n->csn))
+      // DROP("lower sequence number", rcv_csn);
+    {
+      /* We want to report both new and old CSN */
+      LOG_PKT_AUTH("Authentication failed for nbr %R on %s - "
+		   "lower sequence number (rcv %u, old %u)",
+		   n->rid, ifa->ifname, rcv_csn, n->csn);
       return 0;
-  }
-}
+    }
 
-#else
+    pass = password_find_by_id(ifa->passwords, auth->md5.keyid);
+    if (!pass)
+      DROP("no suitable password found", auth->md5.keyid);
 
-/* OSPFv3 authentication not yet supported */
+    void *tail = ((void *) pkt) + plen;
+    char passwd[OSPF_AUTH_CRYPT_SIZE];
+    char md5sum[OSPF_AUTH_CRYPT_SIZE];
 
-static inline void
-ospf_pkt_finalize(struct ospf_iface *ifa, struct ospf_packet *pkt)
-{ }
+    strncpy(passwd, pass->password, OSPF_AUTH_CRYPT_SIZE);
 
-static int
-ospf_pkt_checkauth(struct ospf_neighbor *n, struct ospf_iface *ifa, struct ospf_packet *pkt, int size)
-{ return 1; }
- 
-#endif
+    struct MD5Context ctxt;
+    MD5Init(&ctxt);
+    MD5Update(&ctxt, (char *) pkt, plen);
+    MD5Update(&ctxt, passwd, OSPF_AUTH_CRYPT_SIZE);
+    MD5Final(md5sum, &ctxt);
+
+    if (memcmp(md5sum, tail, OSPF_AUTH_CRYPT_SIZE))
+      DROP("wrong MD5 digest", pass->id);
+
+    if (n)
+      n->csn = rcv_csn;
+
+    return 1;
+
+  default:
+    bug("Unknown authentication type");
+  }
 
+drop:
+  LOG_PKT_AUTH("Authentication failed for nbr %R on %s - %s (%u)",
+	       (n ? n->rid : ntohl(pkt->routerid)), ifa->ifname, err_dsc, err_val);
+
+  return 0;
+}
 
 /**
  * ospf_rx_hook
@@ -251,13 +215,10 @@ ospf_pkt_checkauth(struct ospf_neighbor *n, struct ospf_iface *ifa, struct ospf_
  * non generic functions.
  */
 int
-ospf_rx_hook(sock *sk, int size)
+ospf_rx_hook(sock *sk, int len)
 {
-  char *mesg = "OSPF: Bad packet from ";
-
-  /* We want just packets from sk->iface. Unfortunately, on BSD we
-     cannot filter out other packets at kernel level and we receive
-     all packets on all sockets */
+  /* We want just packets from sk->iface. Unfortunately, on BSD we cannot filter
+     out other packets at kernel level and we receive all packets on all sockets */
   if (sk->lifindex != sk->iface->index)
     return 1;
 
@@ -266,71 +227,65 @@ ospf_rx_hook(sock *sk, int size)
 
   /* Initially, the packet is associated with the 'master' iface */
   struct ospf_iface *ifa = sk->data;
-  struct proto_ospf *po = ifa->oa->po;
-  // struct proto *p = &po->proto;
+  struct ospf_proto *p = ifa->oa->po;
+  const char *err_dsc = NULL;
+  uint err_val = 0;
 
-  int src_local, dst_local UNUSED, dst_mcast; 
+  int src_local, dst_local, dst_mcast;
   src_local = ipa_in_net(sk->faddr, ifa->addr->prefix, ifa->addr->pxlen);
   dst_local = ipa_equal(sk->laddr, ifa->addr->ip);
-  dst_mcast = ipa_equal(sk->laddr, ifa->all_routers) || ipa_equal(sk->laddr, AllDRouters);
-
-#ifdef OSPFv2
-  /* First, we eliminate packets with strange address combinations.
-   * In OSPFv2, they might be for other ospf_ifaces (with different IP
-   * prefix) on the same real iface, so we don't log it. We enforce
-   * that (src_local || dst_local), therefore we are eliminating all
-   * such cases. 
-   */
-  if (dst_mcast && !src_local)
-    return 1;
-  if (!dst_mcast && !dst_local)
-    return 1;
+  dst_mcast = ipa_equal(sk->laddr, ifa->all_routers) || ipa_equal(sk->laddr, ifa->des_routers);
 
-  /* Ignore my own broadcast packets */
-  if (ifa->cf->real_bcast && ipa_equal(sk->faddr, ifa->addr->ip))
-    return 1;
-#else /* OSPFv3 */
-
-  /* In OSPFv3, src_local and dst_local mean link-local. 
-   * RFC 5340 says that local (non-vlink) packets use
-   * link-local src address, but does not enforce it. Strange.
-   */
-  if (dst_mcast && !src_local)
-    log(L_WARN "OSPF: Received multicast packet from %I (not link-local)", sk->faddr);
-#endif
-
-  /* Second, we check packet size, checksum, and the protocol version */
-  struct ospf_packet *ps = (struct ospf_packet *) ip_skip_header(sk->rbuf, &size);
+  if (ospf_is_v2(p))
+  {
+    /* First, we eliminate packets with strange address combinations.
+     * In OSPFv2, they might be for other ospf_ifaces (with different IP
+     * prefix) on the same real iface, so we don't log it. We enforce
+     * that (src_local || dst_local), therefore we are eliminating all
+     * such cases.
+     */
+    if (dst_mcast && !src_local)
+      return 1;
+    if (!dst_mcast && !dst_local)
+      return 1;
 
-  if (ps == NULL)
+    /* Ignore my own broadcast packets */
+    if (ifa->cf->real_bcast && ipa_equal(sk->faddr, ifa->addr->ip))
+      return 1;
+  }
+  else
   {
-    log(L_ERR "%s%I - bad IP header", mesg, sk->faddr);
-    return 1;
+    /* In OSPFv3, src_local and dst_local mean link-local.
+     * RFC 5340 says that local (non-vlink) packets use
+     * link-local src address, but does not enforce it. Strange.
+     */
+    if (dst_mcast && !src_local)
+      LOG_PKT_WARN("Multicast packet received from non-link-local %I via %s",
+		   sk->faddr, ifa->ifname);
   }
 
+  /* Second, we check packet length, checksum, and the protocol version */
+  struct ospf_packet *pkt = (void *) sk_rx_buffer(sk, &len);
+
+
+  if (pkt == NULL)
+    DROP("bad IP header", len);
+
   if (ifa->check_ttl && (sk->rcv_ttl < 255))
-  {
-    log(L_ERR "%s%I - TTL %d (< 255)", mesg, sk->faddr, sk->rcv_ttl);
-    return 1;
-  }
+    DROP("wrong TTL", sk->rcv_ttl);
 
-  if ((unsigned) size < sizeof(struct ospf_packet))
-  {
-    log(L_ERR "%s%I - too short (%u bytes)", mesg, sk->faddr, size);
-    return 1;
-  }
+  if (len < sizeof(struct ospf_packet))
+    DROP("too short", len);
 
-  uint plen = ntohs(ps->length);
+  if (pkt->version != ospf_get_version(p))
+    DROP("version mismatch", pkt->version);
+
+  uint plen = ntohs(pkt->length);
   if ((plen < sizeof(struct ospf_packet)) || ((plen % 4) != 0))
-  {
-    log(L_ERR "%s%I - invalid length (%u)", mesg, sk->faddr, plen);
-    return 1;
-  }
+    DROP("invalid length", plen);
 
   if (sk->flags & SKF_TRUNCATED)
   {
-    log(L_WARN "%s%I - too large (%d/%d)", mesg, sk->faddr, plen, size);
-
     /* If we have dynamic buffers and received truncated message, we expand RX buffer */
 
     uint bs = plen + 256;
@@ -339,168 +294,149 @@ ospf_rx_hook(sock *sk, int size)
     if (!ifa->cf->rx_buffer && (bs > sk->rbsize))
       sk_set_rbsize(sk, bs);
 
-    return 1;
+    DROP("truncated", plen);
   }
 
-  if (plen > size)
-  {
-    log(L_ERR "%s%I - size field does not match (%d/%d)", mesg, sk->faddr, plen, size);
-    return 1;
-  }
+  if (plen > len)
+    DROP("length mismatch", plen);
 
-  if (ps->version != OSPF_VERSION)
+  if (ospf_is_v2(p) && (pkt->autype != OSPF_AUTH_CRYPT))
   {
-    log(L_ERR "%s%I - version %u", mesg, sk->faddr, ps->version);
-    return 1;
-  }
+    uint hlen = sizeof(struct ospf_packet) + sizeof(union ospf_auth);
+    uint blen = plen - hlen;
+    void *body = ((void *) pkt) + hlen;
 
-#ifdef OSPFv2
-  if ((ps->autype != htons(OSPF_AUTH_CRYPT)) &&
-      (!ipsum_verify(ps, 16, (void *) ps + sizeof(struct ospf_packet),
-		     plen - sizeof(struct ospf_packet), NULL)))
-  {
-    log(L_ERR "%s%I - bad checksum", mesg, sk->faddr);
-    return 1;
+    if (!ipsum_verify(pkt, sizeof(struct ospf_packet), body, blen, NULL))
+      DROP1("invalid checksum");
   }
-#endif
-
 
   /* Third, we resolve associated iface and handle vlinks. */
 
-  u32 areaid = ntohl(ps->areaid);
-  u32 rid = ntohl(ps->routerid);
+  u32 areaid = ntohl(pkt->areaid);
+  u32 rid = ntohl(pkt->routerid);
+  u8 instance_id = pkt->instance_id;
 
-  if ((areaid == ifa->oa->areaid)
-#ifdef OSPFv3
-      && (ps->instance_id == ifa->instance_id)
-#endif
-      )
+  if (areaid == ifa->oa->areaid)
   {
-    /* It is real iface, source should be local (in OSPFv2) */
-#ifdef OSPFv2
-    if (!src_local)
+    /* Matching area ID */
+
+    if (instance_id != ifa->instance_id)
       return 1;
-#endif
-  }
-  else if (dst_mcast || (areaid != 0))
-  {
-    /* Obvious mismatch */
-
-#ifdef OSPFv2
-    /* We ignore mismatch in OSPFv3, because there might be
-       other instance with different instance ID */
-    log(L_ERR "%s%I - area does not match (%R vs %R)",
-	mesg, sk->faddr, areaid, ifa->oa->areaid);
-#endif
-    return 1;
+
+    /* It is real iface, source should be local (in OSPFv2) */
+    if (ospf_is_v2(p) && !src_local)
+      DROP1("strange source address");
+
+    goto found;
   }
-  else
+  else if ((areaid == 0) && !dst_mcast)
   {
-    /* Some vlink? */
-    struct ospf_iface *iff = NULL;
+    /* Backbone area ID and possible vlink packet */
 
-    WALK_LIST(iff, po->iface_list)
+    if ((p->areano == 1) || !oa_is_ext(ifa->oa))
+      return 1;
+
+    struct ospf_iface *iff = NULL;
+    WALK_LIST(iff, p->iface_list)
     {
-      if ((iff->type == OSPF_IT_VLINK) && 
+      if ((iff->type == OSPF_IT_VLINK) &&
 	  (iff->voa == ifa->oa) &&
-#ifdef OSPFv3
-	  (iff->instance_id == ps->instance_id) &&
-#endif
+	  (iff->instance_id == instance_id) &&
 	  (iff->vid == rid))
-	{
-	  /* Vlink should be UP */
-	  if (iff->state != OSPF_IS_PTP)
-	    return 1;
-	  
-	  ifa = iff;
-	  goto found;
-	}
+      {
+	/* Vlink should be UP */
+	if (iff->state != OSPF_IS_PTP)
+	  return 1;
+
+	ifa = iff;
+	goto found;
+      }
     }
 
-#ifdef OSPFv2
-    log(L_WARN "OSPF: Received packet for unknown vlink (ID %R, IP %I)", rid, sk->faddr);
-#endif
+    /*
+     * Cannot find matching vlink. It is either misconfigured vlink; NBMA or
+     * PtMP with misconfigured area ID, or packet for some other instance (that
+     * is possible even if instance_id == ifa->instance_id, because it may be
+     * also vlink packet in the other instance, which is different namespace).
+     */
+
     return 1;
   }
+  else
+  {
+    /* Non-matching area ID but cannot be vlink packet */
 
- found:
+    if (instance_id != ifa->instance_id)
+      return 1;
+
+    DROP("area mismatch", areaid);
+  }
+
+
+found:
   if (ifa->stub)	    /* This shouldn't happen */
     return 1;
 
-  if (ipa_equal(sk->laddr, AllDRouters) && (ifa->sk_dr == 0))
+  if (ipa_equal(sk->laddr, ifa->des_routers) && (ifa->sk_dr == 0))
     return 1;
 
-  if (rid == po->router_id)
-  {
-    log(L_ERR "%s%I - received my own router ID!", mesg, sk->faddr);
-    return 1;
-  }
+  if (rid == p->router_id)
+    DROP1("my own router ID");
 
   if (rid == 0)
-  {
-    log(L_ERR "%s%I - router id = 0.0.0.0", mesg, sk->faddr);
-    return 1;
-  }
+    DROP1("zero router ID");
 
-#ifdef OSPFv2
-  /* In OSPFv2, neighbors are identified by either IP or Router ID, base on network type */
+  /* In OSPFv2, neighbors are identified by either IP or Router ID, based on network type */
+  uint t = ifa->type;
   struct ospf_neighbor *n;
-  if ((ifa->type == OSPF_IT_BCAST) || (ifa->type == OSPF_IT_NBMA) || (ifa->type == OSPF_IT_PTMP))
+  if (ospf_is_v2(p) && ((t == OSPF_IT_BCAST) || (t == OSPF_IT_NBMA) || (t == OSPF_IT_PTMP)))
     n = find_neigh_by_ip(ifa, sk->faddr);
   else
     n = find_neigh(ifa, rid);
-#else
-  struct ospf_neighbor *n = find_neigh(ifa, rid);
-#endif
 
-  if(!n && (ps->type != HELLO_P))
+  if (!n && (pkt->type != HELLO_P))
   {
-    log(L_WARN "OSPF: Received non-hello packet from unknown neighbor (src %I, iface %s)",
-	sk->faddr, ifa->ifname);
+    OSPF_TRACE(D_PACKETS, "Non-HELLO packet received from unknown nbr %R on %s, src %I",
+	       rid, ifa->ifname, sk->faddr);
     return 1;
   }
 
-  if (!ospf_pkt_checkauth(n, ifa, ps, size))
-  {
-    log(L_ERR "%s%I - authentication failed", mesg, sk->faddr);
+  /* ospf_pkt_checkauth() has its own error logging */
+  if (ospf_is_v2(p) && !ospf_pkt_checkauth(n, ifa, pkt, len))
     return 1;
-  }
-
-  /* Dump packet 
-     pu8=(u8 *)(sk->rbuf+5*4);
-     for(i=0;i<ntohs(ps->length);i+=4)
-     DBG("%s: received %u,%u,%u,%u\n",p->name, pu8[i+0], pu8[i+1], pu8[i+2],
-     pu8[i+3]);
-     DBG("%s: received size: %u\n",p->name,size);
-   */
 
-  switch (ps->type)
+  switch (pkt->type)
   {
   case HELLO_P:
-    DBG("%s: Hello received.\n", p->name);
-    ospf_hello_receive(ps, ifa, n, sk->faddr);
+    ospf_receive_hello(pkt, ifa, n, sk->faddr);
     break;
+
   case DBDES_P:
-    DBG("%s: Database description received.\n", p->name);
-    ospf_dbdes_receive(ps, ifa, n);
+    ospf_receive_dbdes(pkt, ifa, n);
     break;
+
   case LSREQ_P:
-    DBG("%s: Link state request received.\n", p->name);
-    ospf_lsreq_receive(ps, ifa, n);
+    ospf_receive_lsreq(pkt, ifa, n);
     break;
+
   case LSUPD_P:
-    DBG("%s: Link state update received.\n", p->name);
-    ospf_lsupd_receive(ps, ifa, n);
+    ospf_receive_lsupd(pkt, ifa, n);
     break;
+
   case LSACK_P:
-    DBG("%s: Link state ack received.\n", p->name);
-    ospf_lsack_receive(ps, ifa, n);
+    ospf_receive_lsack(pkt, ifa, n);
     break;
+
   default:
-    log(L_ERR "%s%I - wrong type %u", mesg, sk->faddr, ps->type);
-    return 1;
+    DROP("invalid packet type", pkt->type);
   };
   return 1;
+
+drop:
+  LOG_PKT("Bad packet from %I via %s - %s (%u)",
+	  sk->faddr, ifa->ifname, err_dsc, err_val);
+
+  return 1;
 }
 
 /*
@@ -508,7 +444,7 @@ void
 ospf_tx_hook(sock * sk)
 {
   struct ospf_iface *ifa= (struct ospf_iface *) (sk->data);
-//  struct proto *p = (struct proto *) (ifa->oa->po);
+//  struct proto *p = (struct proto *) (ifa->oa->p);
   log(L_ERR "OSPF: TX hook called on %s", ifa->ifname);
 }
 */
@@ -517,16 +453,35 @@ void
 ospf_err_hook(sock * sk, int err)
 {
   struct ospf_iface *ifa= (struct ospf_iface *) (sk->data);
-  struct proto *p = &(ifa->oa->po->proto);
-  log(L_ERR "%s: Socket error on %s: %M", p->name, ifa->ifname, err);
+  struct ospf_proto *p = ifa->oa->po;
+  log(L_ERR "%s: Socket error on %s: %M", p->p.name, ifa->ifname, err);
 }
 
 void
 ospf_verr_hook(sock *sk, int err)
 {
-  struct proto_ospf *po = (struct proto_ospf *) (sk->data);
-  struct proto *p =  &po->proto;
-  log(L_ERR "%s: Vlink socket error: %M", p->name, err);
+  struct ospf_proto *p = (struct ospf_proto *) (sk->data);
+  log(L_ERR "%s: Vlink socket error: %M", p->p.name, err);
+}
+
+void
+ospf_send_to(struct ospf_iface *ifa, ip_addr dst)
+{
+  sock *sk = ifa->sk;
+  struct ospf_packet *pkt = (struct ospf_packet *) sk->tbuf;
+  int plen = ntohs(pkt->length);
+
+  if (ospf_is_v2(ifa->oa->po))
+  {
+    if (ifa->autype == OSPF_AUTH_CRYPT)
+      plen += OSPF_AUTH_CRYPT_SIZE;
+
+    ospf_pkt_finalize(ifa, pkt);
+  }
+
+  int done = sk_send_to(sk, plen, dst, 0);
+  if (!done)
+    log(L_WARN "OSPF: TX queue full on %s", ifa->ifname);
 }
 
 void
@@ -542,28 +497,8 @@ ospf_send_to_agt(struct ospf_iface *ifa, u8 state)
 void
 ospf_send_to_bdr(struct ospf_iface *ifa)
 {
-  if (!ipa_equal(ifa->drip, IPA_NONE))
+  if (ipa_nonzero(ifa->drip))
     ospf_send_to(ifa, ifa->drip);
-  if (!ipa_equal(ifa->bdrip, IPA_NONE))
+  if (ipa_nonzero(ifa->bdrip))
     ospf_send_to(ifa, ifa->bdrip);
 }
-
-void
-ospf_send_to(struct ospf_iface *ifa, ip_addr dst)
-{
-  sock *sk = ifa->sk;
-  struct ospf_packet *pkt = (struct ospf_packet *) sk->tbuf;
-  int len = ntohs(pkt->length);
-
-#ifdef OSPFv2
-  if (ifa->autype == OSPF_AUTH_CRYPT)
-    len += OSPF_AUTH_CRYPT_SIZE;
-#endif
-
-  ospf_pkt_finalize(ifa, pkt);
-
-  int done = sk_send_to(sk, len, dst, 0);
-  if (!done)
-    log(L_WARN "OSPF: TX queue full on %s", ifa->ifname);
-}
-