/* * BIRD -- OSPF * * (c) 2000--2004 Ondrej Filip <feela@network.cz> * * Can be freely distributed and used under the terms of the GNU GPL. */ #include "ospf.h" struct ospf_lsupd_packet { struct ospf_packet ospf_packet; u32 lsano; /* Number of LSA's */ }; /* Beware of unaligned access */ void ospf_dump_lsahdr(struct proto *p, struct ospf_lsa_header *lsa_n) { struct ospf_lsa_header lsa; ntohlsah(lsa_n, &lsa); log(L_TRACE "%s: LSA Type: %04x, Id: %R, Rt: %R, Age: %u, Seq: %08x, Sum: %04x", p->name, lsa.type, lsa.id, lsa.rt, lsa.age, lsa.sn, lsa.checksum); } void ospf_dump_common(struct proto *p, struct ospf_packet *op) { log(L_TRACE "%s: length %d", p->name, ntohs(op->length)); log(L_TRACE "%s: router %R", p->name, ntohl(op->routerid)); } static void ospf_dump_lsupd(struct proto *p, struct ospf_lsupd_packet *pkt) { struct ospf_packet *op = &pkt->ospf_packet; ASSERT(op->type == LSUPD_P); ospf_dump_common(p, op); /* We know that ntohs(op->length) >= sizeof(struct ospf_lsa_header) */ u8 *pbuf= (u8 *) pkt; unsigned int offset = sizeof(struct ospf_lsupd_packet); unsigned int bound = ntohs(op->length) - sizeof(struct ospf_lsa_header); unsigned int i, j, lsalen; j = ntohl(pkt->lsano); for (i = 0; i < j; i++) { if (offset > bound) { log(L_TRACE "%s: LSA invalid", p->name); return; } struct ospf_lsa_header *lsa = (void *) (pbuf + offset); ospf_dump_lsahdr(p, lsa); lsalen = ntohs(lsa->length); offset += lsalen; if (((lsalen % 4) != 0) || (lsalen <= sizeof(struct ospf_lsa_header))) { log(L_TRACE "%s: LSA invalid", p->name); return; } } } #ifdef OSPFv2 int ospf_lsa_flooding_allowed(struct ospf_lsa_header *lsa, u32 domain, struct ospf_iface *ifa) { if (lsa->type == LSA_T_EXT) { if (ifa->type == OSPF_IT_VLINK) return 0; if (!oa_is_ext(ifa->oa)) return 0; return 1; } else return ifa->oa->areaid == domain; } #else /* OSPFv3 */ static int unknown_lsa_type(struct ospf_lsa_header *lsa) { switch (lsa->type) { case LSA_T_RT: case LSA_T_NET: case LSA_T_SUM_NET: case LSA_T_SUM_RT: case LSA_T_EXT: case LSA_T_NSSA: case LSA_T_LINK: case LSA_T_PREFIX: return 0; default: return 1; } } int ospf_lsa_flooding_allowed(struct ospf_lsa_header *lsa, u32 domain, struct ospf_iface *ifa) { u32 scope = LSA_SCOPE(lsa); /* Handle inactive vlinks */ if (ifa->state == OSPF_IS_DOWN) return 0; /* 4.5.2 (Case 2) */ if (unknown_lsa_type(lsa) && !(lsa->type & LSA_UBIT)) scope = LSA_SCOPE_LINK; switch (scope) { case LSA_SCOPE_LINK: return ifa->iface_id == domain; case LSA_SCOPE_AREA: return ifa->oa->areaid == domain; case LSA_SCOPE_AS: if (ifa->type == OSPF_IT_VLINK) return 0; if (!oa_is_ext(ifa->oa)) return 0; return 1; default: log(L_ERR "LSA with invalid scope"); return 0; } } #endif /** * ospf_lsupd_flood - send received or generated lsa to the neighbors * @po: OSPF protocol * @n: neighbor than sent this lsa (or NULL if generated) * @hn: LSA header followed by lsa body in network endianity (may be NULL) * @hh: LSA header in host endianity (must be filled) * @domain: domain of LSA (must be filled) * @rtl: add this LSA into retransmission list * * * return value - was the LSA flooded back? */ int ospf_lsupd_flood(struct proto_ospf *po, struct ospf_neighbor *n, struct ospf_lsa_header *hn, struct ospf_lsa_header *hh, u32 domain, int rtl) { struct ospf_iface *ifa; struct ospf_neighbor *nn; struct top_hash_entry *en; struct proto *p = &po->proto; int ret, retval = 0; /* pg 148 */ WALK_LIST(ifa, po->iface_list) { if (ifa->stub) continue; if (! ospf_lsa_flooding_allowed(hh, domain, ifa)) continue; DBG("Wanted to flood LSA: Type: %u, ID: %R, RT: %R, SN: 0x%x, Age %u\n", hh->type, hh->id, hh->rt, hh->sn, hh->age); ret = 0; WALK_LIST(nn, ifa->neigh_list) { /* 13.3 (1a) */ if (nn->state < NEIGHBOR_EXCHANGE) continue; /* 13.3 (1b) */ if (nn->state < NEIGHBOR_FULL) { if ((en = ospf_hash_find_header(nn->lsrqh, domain, hh)) != NULL) { DBG("That LSA found in lsreq list for neigh %R\n", nn->rid); switch (lsa_comp(hh, &en->lsa)) { case CMP_OLDER: continue; break; case CMP_SAME: s_rem_node(SNODE en); if (en->lsa_body != NULL) mb_free(en->lsa_body); en->lsa_body = NULL; DBG("Removing from lsreq list for neigh %R\n", nn->rid); ospf_hash_delete(nn->lsrqh, en); if ((EMPTY_SLIST(nn->lsrql)) && (nn->state == NEIGHBOR_LOADING)) ospf_neigh_sm(nn, INM_LOADDONE); continue; break; case CMP_NEWER: s_rem_node(SNODE en); if (en->lsa_body != NULL) mb_free(en->lsa_body); en->lsa_body = NULL; DBG("Removing from lsreq list for neigh %R\n", nn->rid); ospf_hash_delete(nn->lsrqh, en); if ((EMPTY_SLIST(nn->lsrql)) && (nn->state == NEIGHBOR_LOADING)) ospf_neigh_sm(nn, INM_LOADDONE); break; default: bug("Bug in lsa_comp?"); } } } /* 13.3 (1c) */ if (nn == n) continue; /* 13.3 (1d) */ if (rtl) { /* In OSPFv3, there should be check whether receiving router understand that type of LSA (for LSA types with U-bit == 0). But as we does not support any optional LSA types, this is not needed yet */ if ((en = ospf_hash_find_header(nn->lsrth, domain, hh)) == NULL) { en = ospf_hash_get_header(nn->lsrth, domain, hh); } else { s_rem_node(SNODE en); } s_add_tail(&nn->lsrtl, SNODE en); memcpy(&en->lsa, hh, sizeof(struct ospf_lsa_header)); DBG("Adding that LSA for flood to %I\n", nn->ip); } else { if ((en = ospf_hash_find_header(nn->lsrth, domain, hh)) != NULL) { s_rem_node(SNODE en); ospf_hash_delete(nn->lsrth, en); } } ret = 1; } if (ret == 0) continue; /* pg 150 (2) */ if (n && (n->ifa == ifa)) { if ((n->rid == ifa->drid) || n->rid == ifa->bdrid) continue; /* pg 150 (3) */ if (ifa->state == OSPF_IS_BACKUP) continue; /* pg 150 (4) */ retval = 1; } { u16 len, age; struct ospf_lsupd_packet *pk; struct ospf_packet *op; struct ospf_lsa_header *lh; /* Check iface buffer size */ uint len2 = sizeof(struct ospf_lsupd_packet) + (hn ? ntohs(hn->length) : hh->length); if (ospf_iface_assure_bufsize(ifa, len2) < 0) { /* Cannot fit in a tx buffer, skip that iface */ log(L_ERR "OSPF: LSA too large to flood on %s (Type: %04x, Id: %R, Rt: %R)", ifa->ifname, hh->type, hh->id, hh->rt); continue; } pk = ospf_tx_buffer(ifa); op = &pk->ospf_packet; ospf_pkt_fill_hdr(ifa, pk, LSUPD_P); pk->lsano = htonl(1); lh = (struct ospf_lsa_header *) (pk + 1); /* Copy LSA into the packet */ if (hn) { memcpy(lh, hn, ntohs(hn->length)); } else { u8 *help; struct top_hash_entry *en; htonlsah(hh, lh); help = (u8 *) (lh + 1); en = ospf_hash_find_header(po->gr, domain, hh); htonlsab(en->lsa_body, help, hh->length - sizeof(struct ospf_lsa_header)); } len = sizeof(struct ospf_lsupd_packet) + ntohs(lh->length); age = ntohs(lh->age); age += ifa->inftransdelay; if (age > LSA_MAXAGE) age = LSA_MAXAGE; lh->age = htons(age); op->length = htons(len); OSPF_PACKET(ospf_dump_lsupd, pk, "LSUPD packet flooded via %s", ifa->ifname); switch (ifa->type) { case OSPF_IT_BCAST: if ((ifa->state == OSPF_IS_BACKUP) || (ifa->state == OSPF_IS_DR)) ospf_send_to_all(ifa); else if (ifa->cf->real_bcast) ospf_send_to_bdr(ifa); else ospf_send_to(ifa, AllDRouters); break; case OSPF_IT_NBMA: if ((ifa->state == OSPF_IS_BACKUP) || (ifa->state == OSPF_IS_DR)) ospf_send_to_agt(ifa, NEIGHBOR_EXCHANGE); else ospf_send_to_bdr(ifa); break; case OSPF_IT_PTP: ospf_send_to_all(ifa); break; case OSPF_IT_PTMP: ospf_send_to_agt(ifa, NEIGHBOR_EXCHANGE); break; case OSPF_IT_VLINK: ospf_send_to(ifa, ifa->vip); break; default: bug("Bug in ospf_lsupd_flood()"); } } } return retval; } void /* I send all I received in LSREQ */ ospf_lsupd_send_list(struct ospf_neighbor *n, list * l) { struct ospf_area *oa = n->ifa->oa; struct proto *p = &oa->po->proto; struct l_lsr_head *lsr; struct top_hash_entry *en; struct ospf_lsupd_packet *pkt; u32 len, len2, lsano; char *buf; pkt = ospf_tx_buffer(n->ifa); buf = (void *) pkt; lsr = HEAD(*l); while(NODE_NEXT(lsr)) { /* Prepare the packet */ ospf_pkt_fill_hdr(n->ifa, pkt, LSUPD_P); len = sizeof(struct ospf_lsupd_packet); lsano = 0; /* Fill the packet with LSAs */ while(NODE_NEXT(lsr)) { u32 domain = ospf_lsa_domain(lsr->lsh.type, n->ifa); en = ospf_hash_find(oa->po->gr, domain, lsr->lsh.id, lsr->lsh.rt, lsr->lsh.type); if (en == NULL) { /* Probably flushed LSA, this should not happen */ // log(L_WARN "OSPF: LSA disappeared (Type: %04x, Id: %R, Rt: %R)", lsr->lsh.type, lsr->lsh.id, lsr->lsh.rt); lsr = NODE_NEXT(lsr); continue; } len2 = len + en->lsa.length; if (len2 > ospf_pkt_maxsize(n->ifa)) { /* The packet if full, stop adding LSAs and sent it */ if (lsano > 0) break; /* LSA is larger than MTU, check buffer size */ if (ospf_iface_assure_bufsize(n->ifa, len2) < 0) { /* Cannot fit in a tx buffer, skip that */ log(L_ERR "OSPF: LSA too large to send (Type: %04x, Id: %R, Rt: %R)", lsr->lsh.type, lsr->lsh.id, lsr->lsh.rt); lsr = NODE_NEXT(lsr); continue; } /* TX buffer could be reallocated */ pkt = ospf_tx_buffer(n->ifa); buf = (void *) pkt; } /* Copy the LSA to the packet */ htonlsah(&(en->lsa), (struct ospf_lsa_header *) (buf + len)); htonlsab(en->lsa_body, buf + len + sizeof(struct ospf_lsa_header), en->lsa.length - sizeof(struct ospf_lsa_header)); len = len2; lsano++; lsr = NODE_NEXT(lsr); } if (lsano == 0) break; /* Send the packet */ pkt->lsano = htonl(lsano); pkt->ospf_packet.length = htons(len); OSPF_PACKET(ospf_dump_lsupd, pkt, "LSUPD packet sent to %I via %s", n->ip, n->ifa->ifname); ospf_send_to(n->ifa, n->ip); } } void ospf_lsupd_receive(struct ospf_packet *ps_i, struct ospf_iface *ifa, struct ospf_neighbor *n) { struct ospf_neighbor *ntmp; struct proto_ospf *po = ifa->oa->po; struct proto *p = &po->proto; unsigned int i, max, sendreq = 1; unsigned int size = ntohs(ps_i->length); if (size < (sizeof(struct ospf_lsupd_packet) + sizeof(struct ospf_lsa_header))) { log(L_ERR "OSPF: Bad LSUPD packet from %I - too short (%u B)", n->ip, size); return; } struct ospf_lsupd_packet *ps = (void *) ps_i; OSPF_PACKET(ospf_dump_lsupd, ps, "LSUPD packet received from %I via %s", n->ip, ifa->ifname); if (n->state < NEIGHBOR_EXCHANGE) { OSPF_TRACE(D_PACKETS, "Received lsupd in lesser state than EXCHANGE from (%I)", n->ip); return; } ospf_neigh_sm(n, INM_HELLOREC); /* Questionable */ unsigned int offset = sizeof(struct ospf_lsupd_packet); unsigned int bound = size - sizeof(struct ospf_lsa_header); max = ntohl(ps->lsano); for (i = 0; i < max; i++) { struct ospf_lsa_header lsatmp; struct top_hash_entry *lsadb; if (offset > bound) { log(L_WARN "Received lsupd from %I is too short!", n->ip); ospf_neigh_sm(n, INM_BADLSREQ); return; } struct ospf_lsa_header *lsa = (void *) (((u8 *) ps) + offset); unsigned int lsalen = ntohs(lsa->length); offset += lsalen; if ((offset > size) || ((lsalen % 4) != 0) || (lsalen <= sizeof(struct ospf_lsa_header))) { log(L_WARN "Received LSA from %I with bad length", n->ip); ospf_neigh_sm(n, INM_BADLSREQ); break; } /* pg 143 (1) */ u16 chsum = lsa->checksum; if (chsum != lsasum_check(lsa, NULL)) { log(L_WARN "Received bad lsa checksum from %I: %x %x", n->ip, chsum, lsa->checksum); continue; } #ifdef OSPFv2 /* pg 143 (2) */ if ((lsa->type == 0) || (lsa->type == 6) || (lsa->type > LSA_T_NSSA)) { log(L_WARN "Unknown LSA type from %I", n->ip); continue; } /* pg 143 (3) */ if ((lsa->type == LSA_T_EXT) && !oa_is_ext(ifa->oa)) { log(L_WARN "Received External LSA in stub area from %I", n->ip); continue; } #else /* OSPFv3 */ u16 scope = ntoht(lsa->type) & LSA_SCOPE_MASK; /* 4.5.1 (2) */ if ((scope == LSA_SCOPE_AS) && !oa_is_ext(ifa->oa)) { log(L_WARN "Received LSA with AS scope in stub area from %I", n->ip); continue; } /* 4.5.1 (3) */ if (scope == LSA_SCOPE_RES) { log(L_WARN "Received LSA with invalid scope from %I", n->ip); continue; } #endif ntohlsah(lsa, &lsatmp); DBG("Update Type: %u ID: %R RT: %R, Sn: 0x%08x Age: %u, Sum: %u\n", lsatmp.type, lsatmp.id, lsatmp.rt, lsatmp.sn, lsatmp.age, lsatmp.checksum); /* FIXME domain should be link id for unknown LSA types with zero Ubit */ u32 domain = ospf_lsa_domain(lsatmp.type, ifa); lsadb = ospf_hash_find_header(po->gr, domain, &lsatmp); #ifdef LOCAL_DEBUG if (lsadb) DBG("I have Type: %u ID: %R RT: %R, Sn: 0x%08x Age: %u, Sum: %u\n", lsadb->lsa.type, lsadb->lsa.id, lsadb->lsa.rt, lsadb->lsa.sn, lsadb->lsa.age, lsadb->lsa.checksum); #endif /* pg 143 (4) */ if ((lsatmp.age == LSA_MAXAGE) && (lsadb == NULL) && can_flush_lsa(po)) { ospf_lsack_enqueue(n, lsa, ACKL_DIRECT); continue; } /* pg 144 (5) */ if ((lsadb == NULL) || (lsa_comp(&lsatmp, &lsadb->lsa) == CMP_NEWER)) { struct ospf_iface *ift = NULL; int self = (lsatmp.rt == po->router_id); DBG("PG143(5): Received LSA is newer\n"); #ifdef OSPFv2 /* 13.4 - check self-originated LSAs of NET type */ if ((!self) && (lsatmp.type == LSA_T_NET)) { struct ospf_iface *nifa; WALK_LIST(nifa, po->iface_list) { if (!nifa->iface) continue; if (ipa_equal(nifa->addr->ip, ipa_from_u32(lsatmp.id))) { self = 1; break; } } } #endif /* pg 145 (5f) - premature aging of self originated lsa */ if (self) { if ((lsatmp.age == LSA_MAXAGE) && (lsatmp.sn == LSA_MAXSEQNO)) { ospf_lsack_enqueue(n, lsa, ACKL_DIRECT); continue; } OSPF_TRACE(D_EVENTS, "Received old self-originated LSA (Type: %04x, Id: %R, Rt: %R)", lsatmp.type, lsatmp.id, lsatmp.rt); if (lsadb) { OSPF_TRACE(D_EVENTS, "Reflooding new self-originated LSA with newer sequence number"); lsadb->lsa.sn = lsatmp.sn + 1; lsadb->lsa.age = 0; lsadb->inst_t = now; lsadb->ini_age = 0; lsasum_calculate(&lsadb->lsa, lsadb->lsa_body); ospf_lsupd_flood(po, NULL, NULL, &lsadb->lsa, domain, 1); } else { OSPF_TRACE(D_EVENTS, "Premature aging it"); lsatmp.age = LSA_MAXAGE; lsatmp.sn = LSA_MAXSEQNO; lsa->age = htons(LSA_MAXAGE); lsa->sn = htonl(LSA_MAXSEQNO); lsasum_check(lsa, (lsa + 1)); /* It also calculates chsum! */ lsatmp.checksum = ntohs(lsa->checksum); ospf_lsupd_flood(po, NULL, lsa, &lsatmp, domain, 0); } continue; } /* pg 144 (5a) */ if (lsadb && ((now - lsadb->inst_t) <= MINLSARRIVAL)) /* FIXME: test for flooding? */ { OSPF_TRACE(D_EVENTS, "Skipping LSA received in less that MINLSARRIVAL"); sendreq = 0; continue; } /* Remove old from all ret lists */ /* pg 144 (5c) */ /* Must be done before (5b), otherwise it also removes the new entries from (5b) */ if (lsadb) WALK_LIST(ift, po->iface_list) WALK_LIST(ntmp, ift->neigh_list) { struct top_hash_entry *en; if (ntmp->state > NEIGHBOR_EXSTART) if ((en = ospf_hash_find_header(ntmp->lsrth, domain, &lsadb->lsa)) != NULL) { s_rem_node(SNODE en); ospf_hash_delete(ntmp->lsrth, en); } } /* pg 144 (5b) */ if (ospf_lsupd_flood(po, n, lsa, &lsatmp, domain, 1) == 0) { DBG("Wasn't flooded back\n"); /* ps 144(5e), pg 153 */ if (ifa->state == OSPF_IS_BACKUP) { if (ifa->drid == n->rid) ospf_lsack_enqueue(n, lsa, ACKL_DELAY); } else ospf_lsack_enqueue(n, lsa, ACKL_DELAY); } if ((lsatmp.age == LSA_MAXAGE) && (lsatmp.sn == LSA_MAXSEQNO) && lsadb && can_flush_lsa(po)) { flush_lsa(lsadb, po); schedule_rtcalc(po); continue; } /* FIXME lsack? */ /* pg 144 (5d) */ void *body = mb_alloc(p->pool, lsatmp.length - sizeof(struct ospf_lsa_header)); ntohlsab(lsa + 1, body, lsatmp.length - sizeof(struct ospf_lsa_header)); /* We will do validation check after flooding and acknowledging given LSA to minimize problems when communicating with non-validating peer */ if (lsa_validate(&lsatmp, body) == 0) { log(L_WARN "Received invalid LSA from %I", n->ip); mb_free(body); continue; } lsadb = lsa_install_new(po, &lsatmp, domain, body); DBG("New LSA installed in DB\n"); #ifdef OSPFv3 /* Events 6,7 from RFC5340 4.4.3. */ if ((lsatmp.type == LSA_T_LINK) && (ifa->state == OSPF_IS_DR)) schedule_net_lsa(ifa); #endif continue; } /* FIXME pg145 (6) */ /* pg145 (7) */ if (lsa_comp(&lsatmp, &lsadb->lsa) == CMP_SAME) { struct top_hash_entry *en; DBG("PG145(7) Got the same LSA\n"); if ((en = ospf_hash_find_header(n->lsrth, lsadb->domain, &lsadb->lsa)) != NULL) { /* pg145 (7a) */ s_rem_node(SNODE en); ospf_hash_delete(n->lsrth, en); if (ifa->state == OSPF_IS_BACKUP) { if (n->rid == ifa->drid) ospf_lsack_enqueue(n, lsa, ACKL_DELAY); } } else { /* pg145 (7b) */ ospf_lsack_enqueue(n, lsa, ACKL_DIRECT); } sendreq = 0; continue; } /* pg145 (8) */ if ((lsadb->lsa.age == LSA_MAXAGE) && (lsadb->lsa.sn == LSA_MAXSEQNO)) { continue; } { list l; struct l_lsr_head ll; init_list(&l); ll.lsh.id = lsadb->lsa.id; ll.lsh.rt = lsadb->lsa.rt; ll.lsh.type = lsadb->lsa.type; add_tail(&l, NODE & ll); ospf_lsupd_send_list(n, &l); } } /* Send direct LSAs */ ospf_lsack_send(n, ACKL_DIRECT); if (sendreq && (n->state == NEIGHBOR_LOADING)) { ospf_lsreq_send(n); /* Ask for another part of neighbor's database */ } } void ospf_lsupd_flush_nlsa(struct proto_ospf *po, struct top_hash_entry *en) { struct ospf_lsa_header *lsa = &en->lsa; struct proto *p = &po->proto; lsa->age = LSA_MAXAGE; lsa->sn = LSA_MAXSEQNO; lsasum_calculate(lsa, en->lsa_body); OSPF_TRACE(D_EVENTS, "Premature aging self originated lsa!"); OSPF_TRACE(D_EVENTS, "Type: %04x, Id: %R, Rt: %R", lsa->type, lsa->id, lsa->rt); ospf_lsupd_flood(po, NULL, NULL, lsa, en->domain, 0); }