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-rw-r--r--proto/ospf/packet.c161
1 files changed, 95 insertions, 66 deletions
diff --git a/proto/ospf/packet.c b/proto/ospf/packet.c
index 81686d2..6697057 100644
--- a/proto/ospf/packet.c
+++ b/proto/ospf/packet.c
@@ -255,55 +255,6 @@ ospf_pkt_checkauth(struct ospf_neighbor *n, struct ospf_iface *ifa, struct ospf_
#endif
-static struct ospf_iface *
-find_matching_iface(struct ospf_packet *ps, unsigned ifindex, ip_addr faddr)
-{
- u32 areaid = ntohl(ps->areaid);
- u32 rid = ntohl(ps->routerid);
- node *nd;
-
- /* First, we will try to match real ifaces */
-
- WALK_LIST(nd, ospf_ifaces)
- {
- struct ospf_iface *ifa = SKIP_BACK(struct ospf_iface, sk_node, nd);
- struct ifa *addr = ifa->addr;
-
- if ((ifa->iface->index == ifindex) &&
- (ifa->oa->areaid == areaid) &&
-#ifdef OSPFv2
- ((addr->flags & IA_UNNUMBERED) ?
- ipa_equal(faddr, addr->opposite) :
- ipa_in_net(faddr, addr->prefix, addr->pxlen))
-#else /* OSPFv3 */
- (ifa->instance_id == ps->instance_id)
-#endif
- )
- return ifa;
- }
-
- /* Second, we will try to match vlinks */
-
- if (areaid != 0)
- return NULL;
-
- /* FIXME: There should be some more checks to distinquish parallel
- vlinks to the same ABR. */
-
- WALK_LIST(nd, ospf_vlinks)
- {
- struct ospf_iface *ifa = SKIP_BACK(struct ospf_iface, sk_node, nd);
-
- if ((ifa->vid == rid)
-#ifdef OSPFv3
- && (ifa->instance_id == ps->instance_id)
-#endif
- )
- return ifa;
- }
-
- return NULL;
-}
/**
* ospf_rx_hook
@@ -319,9 +270,47 @@ ospf_rx_hook(sock *sk, int size)
{
char *mesg = "OSPF: Bad packet from ";
- DBG("OSPF: RX_Hook called (from %I)\n", sk->faddr);
+ /* 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;
+
+ DBG("OSPF: RX hook called (iface %s, src %I, dst %I)\n",
+ sk->iface->name, sk->faddr, sk->laddr);
+
+ /* 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;
+
+ int src_local = ifa_match_addr(ifa->addr, sk->faddr);
+ int dst_local = ipa_equal(sk->laddr, ifa->addr->ip);
+ int dst_mcast = ipa_equal(sk->laddr, AllSPFRouters) || 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;
- /* First, we check packet size, checksum, and the protocol version */
+#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 (ps == NULL)
@@ -366,38 +355,78 @@ ospf_rx_hook(sock *sk, int size)
#endif
- /* Now, we would like to associate the packet with an OSPF iface */
- struct ospf_iface *ifa = find_matching_iface(ps, sk->lifindex, sk->faddr);
- if (ifa == NULL)
+ /* Third, we resolve associated iface and handle vlinks. */
+
+ u32 areaid = ntohl(ps->areaid);
+ u32 rid = ntohl(ps->routerid);
+
+ if ((areaid == ifa->oa->areaid)
+#ifdef OSPFv3
+ && (ps->instance_id != ifa->instance_id)
+#endif
+ )
+ {
+ /* It is real iface, source should be local (in OSPFv2) */
+#ifdef OSPFv2
+ if (!src_local)
+ 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;
+ }
+ else
{
- /* We limit logging of unmatched packets as it may be perfectly OK */
- if (unmatched_count < 8)
+ /* Some vlink? */
+ struct ospf_iface *iff = NULL;
+
+ WALK_LIST(iff, po->iface_list)
{
- struct iface *ifc = if_find_by_index(sk->lifindex);
- log(L_WARN "OSPF: Received unmatched packet (src %I, iface %s, rtid %R, area %R)",
- sk->faddr, ifc ? ifc->name : "?", ntohl(ps->routerid), ntohl(ps->areaid));
- unmatched_count++;
+ if ((iff->type == OSPF_IT_VLINK) &&
+ (iff->voa == ifa->oa) &&
+#ifdef OSPFv3
+ (iff->instance_id == ps->instance_id) &&
+#endif
+ (iff->vid == rid))
+ {
+ /* 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 uknown vlink (ID %R, IP %I)", rid, sk->faddr);
+#endif
return 1;
}
- struct proto_ospf *po = ifa->oa->po;
- struct proto *p = &po->proto;
-
+ found:
if (ifa->stub) /* This shouldn't happen */
return 1;
if (ipa_equal(sk->laddr, AllDRouters) && (ifa->sk_dr == 0))
return 1;
- if (ntohl(ps->routerid) == po->router_id)
+ if (rid == po->router_id)
{
log(L_ERR "%s%I - received my own router ID!", mesg, sk->faddr);
return 1;
}
- if (ntohl(ps->routerid) == 0)
+ if (rid == 0)
{
log(L_ERR "%s%I - router id = 0.0.0.0", mesg, sk->faddr);
return 1;
@@ -406,7 +435,7 @@ ospf_rx_hook(sock *sk, int size)
/* This is deviation from RFC 2328 - neighbours should be identified by
* IP address on broadcast and NBMA networks.
*/
- struct ospf_neighbor *n = find_neigh(ifa, ntohl(ps->routerid));
+ struct ospf_neighbor *n = find_neigh(ifa, rid);
if(!n && (ps->type != HELLO_P))
{