From 52572e94ec75728c114f47db37aaf220c1af29d6 Mon Sep 17 00:00:00 2001 From: Ondrej Zajicek Date: Sun, 23 May 2010 12:34:09 +0200 Subject: [PATCH] Check for OSPF seqnum wraparound and handle it. --- proto/ospf/topology.c | 39 ++++++++++++++++++++++++--------------- 1 file changed, 24 insertions(+), 15 deletions(-) diff --git a/proto/ospf/topology.c b/proto/ospf/topology.c index ebcc31d2..59e9c29d 100644 --- a/proto/ospf/topology.c +++ b/proto/ospf/topology.c @@ -137,6 +137,22 @@ lsab_end(struct proto_ospf *po) return ((byte *) po->lsab) + po->lsab_used; } +static s32 +get_seqnum(struct top_hash_entry *en) +{ + if (!en) + return LSA_INITSEQNO; + + if (en->lsa.sn == LSA_MAXSEQNO) + { + log(L_WARN, "OSPF: Premature origination of LSA (Type: %04x, Id: %R, Rt: %R)", + en->lsa.type, en->lsa.id, en->lsa.rt); + return LSA_INITSEQNO; + } + + return en->lsa.sn++; +} + static int configured_stubnet(struct ospf_area *oa, struct ifa *a) @@ -436,7 +452,7 @@ originate_rt_lsa(struct ospf_area *oa) #endif lsa.rt = po->router_id; - lsa.sn = oa->rt ? (oa->rt->lsa.sn + 1) : LSA_INITSEQNO; + lsa.sn = get_seqnum(oa->rt); u32 dom = oa->areaid; body = originate_rt_lsa_body(oa, &lsa.length); @@ -550,7 +566,7 @@ originate_net_lsa(struct ospf_iface *ifa) #endif lsa.rt = po->router_id; - lsa.sn = ifa->net_lsa ? (ifa->net_lsa->lsa.sn + 1) : LSA_INITSEQNO; + lsa.sn = get_seqnum(ifa->net_lsa); body = originate_net_lsa_body(ifa, &lsa.length, po); lsasum_calculate(&lsa, body); @@ -730,7 +746,6 @@ originate_sum_net_lsa(struct ospf_area *oa, struct fib_node *fn, int metric) lsa.type = LSA_T_SUM_NET; lsa.id = fibnode_to_lsaid(po, fn); lsa.rt = po->router_id; - lsa.sn = LSA_INITSEQNO; if ((en = ospf_hash_find_header(po->gr, dom, &lsa)) != NULL) { @@ -743,9 +758,8 @@ originate_sum_net_lsa(struct ospf_area *oa, struct fib_node *fn, int metric) if (check_sum_net_lsa_same(en, metric)) return; - - lsa.sn = en->lsa.sn + 1; } + lsa.sn = get_seqnum(en); body = originate_sum_net_lsa_body(po, &lsa.length, fn, metric); lsasum_calculate(&lsa, body); @@ -775,17 +789,14 @@ originate_sum_rt_lsa(struct ospf_area *oa, struct fib_node *fn, int metric, u32 /* In OSPFv3, LSA ID is meaningless, but we still use Router ID of ASBR */ lsa.id = rid; lsa.rt = po->router_id; - lsa.sn = LSA_INITSEQNO; options &= OPTIONS_MASK; - if ((en = ospf_hash_find_header(po->gr, dom, &lsa)) != NULL) { if (check_sum_rt_lsa_same(en, lsa.id, metric, options)) return; - - lsa.sn = en->lsa.sn + 1; } + lsa.sn = get_seqnum(en); body = originate_sum_rt_lsa_body(po, &lsa.length, lsa.id, metric, options); lsasum_calculate(&lsa, body); @@ -977,7 +988,6 @@ originate_ext_lsa(net * n, rte * e, struct proto_ospf *po, lsa.type = LSA_T_EXT; lsa.id = fibnode_to_lsaid(po, fn); lsa.rt = po->router_id; - lsa.sn = LSA_INITSEQNO; /* Compute LSA content */ u32 m1 = ea_get_int(attrs, EA_OSPF_METRIC1, LSINFINITY); @@ -1004,9 +1014,8 @@ originate_ext_lsa(net * n, rte * e, struct proto_ospf *po, if (rv > 0) return; - - lsa.sn = en->lsa.sn + 1; } + lsa.sn = get_seqnum(en); body = originate_ext_lsa_body(po, &lsa.length, n, metric, gw, tag); lsasum_calculate(&lsa, body); @@ -1100,7 +1109,7 @@ originate_link_lsa(struct ospf_iface *ifa) lsa.type = LSA_T_LINK; lsa.id = ifa->iface->index; lsa.rt = po->router_id; - lsa.sn = ifa->link_lsa ? (ifa->link_lsa->lsa.sn + 1) : LSA_INITSEQNO; + lsa.sn = get_seqnum(ifa->link_lsa); u32 dom = ifa->iface->index; body = originate_link_lsa_body(ifa, &lsa.length); @@ -1220,7 +1229,7 @@ originate_prefix_rt_lsa(struct ospf_area *oa) lsa.type = LSA_T_PREFIX; lsa.id = 0; lsa.rt = po->router_id; - lsa.sn = oa->pxr_lsa ? (oa->pxr_lsa->lsa.sn + 1) : LSA_INITSEQNO; + lsa.sn = get_seqnum(oa->pxr_lsa); u32 dom = oa->areaid; body = originate_prefix_rt_lsa_body(oa, &lsa.length); @@ -1352,7 +1361,7 @@ originate_prefix_net_lsa(struct ospf_iface *ifa) lsa.type = LSA_T_PREFIX; lsa.id = ifa->iface->index; lsa.rt = po->router_id; - lsa.sn = ifa->pxn_lsa ? (ifa->pxn_lsa->lsa.sn + 1) : LSA_INITSEQNO; + lsa.sn = get_seqnum(ifa->pxn_lsa); u32 dom = ifa->oa->areaid; body = originate_prefix_net_lsa_body(ifa, &lsa.length);