/* * BIRD -- OSPF * * (c) 1999--2004 Ondrej Filip <feela@network.cz> * * Can be freely distributed and used under the terms of the GNU GPL. */ #include "ospf.h" /** * ospf_dbdes_send - transmit database description packet * @n: neighbor * * Sending of a database description packet is described in 10.6 of RFC 2328. * Reception of each packet is acknowledged in the sequence number of another. * When I send a packet to a neighbor I keep a copy in a buffer. If the neighbor * does not reply, I don't create a new packet but just send the content * of the buffer. */ void ospf_dbdes_send(struct ospf_neighbor *n) { struct ospf_dbdes_packet *pkt; struct ospf_packet *op; struct ospf_iface *ifa = n->ifa; struct ospf_area *oa = ifa->oa; struct proto_ospf *po = oa->po; struct proto *p = &po->proto; u16 length, i, j; if ((oa->rt == NULL) || (EMPTY_LIST(po->lsal))) originate_rt_lsa(oa); switch (n->state) { case NEIGHBOR_EXSTART: /* Send empty packets */ n->myimms.bit.i = 1; pkt = (struct ospf_dbdes_packet *) (ifa->ip_sk->tbuf); op = (struct ospf_packet *) pkt; ospf_pkt_fill_hdr(ifa, pkt, DBDES_P); pkt->iface_mtu = htons(ifa->iface->mtu); pkt->options = oa->opt.byte; pkt->imms = n->myimms; pkt->ddseq = htonl(n->dds); length = sizeof(struct ospf_dbdes_packet); op->length = htons(length); ospf_send_to(ifa->ip_sk, n->ip, ifa); OSPF_TRACE(D_PACKETS, "DB_DES (I) sent to %I via %s.", n->ip, ifa->iface->name); break; case NEIGHBOR_EXCHANGE: n->myimms.bit.i = 0; if (((n->myimms.bit.ms) && (n->dds == n->ddr + 1)) || ((!(n->myimms.bit.ms)) && (n->dds == n->ddr))) { snode *sn; /* Send next */ struct ospf_lsa_header *lsa; pkt = n->ldbdes; op = (struct ospf_packet *) pkt; ospf_pkt_fill_hdr(ifa, pkt, DBDES_P); pkt->iface_mtu = htons(ifa->iface->mtu); pkt->options = oa->opt.byte; pkt->ddseq = htonl(n->dds); j = i = (ospf_pkt_maxsize(ifa) - sizeof(struct ospf_dbdes_packet)) / sizeof(struct ospf_lsa_header); /* Number of possible lsaheaders to send */ lsa = (n->ldbdes + sizeof(struct ospf_dbdes_packet)); if (n->myimms.bit.m) { sn = s_get(&(n->dbsi)); DBG("Number of LSA: %d\n", j); for (; i > 0; i--) { struct top_hash_entry *en= (struct top_hash_entry *) sn; int send = 1; /* Don't send ext LSA into stub areas */ if (oa->stub && (en->lsa.type == LSA_T_EXT)) send = 0; /* Don't send ext LSAs through VLINK */ if ((ifa->type == OSPF_IT_VLINK) && (en->lsa.type == LSA_T_EXT)) send = 0;; /* Don't send LSA of other areas */ if ((en->lsa.type != LSA_T_EXT) && (en->oa != oa)) send = 0; if (send) { htonlsah(&(en->lsa), lsa); DBG("Working on: %d\n", i); DBG("\tX%01x %-1I %-1I %p\n", en->lsa.type, en->lsa.id, en->lsa.rt, en->lsa_body); lsa++; } else i++; /* No lsa added */ if (sn == STAIL(po->lsal)) { i--; break; } sn = sn->next; } if (sn == STAIL(po->lsal)) { DBG("Number of LSA NOT sent: %d\n", i); DBG("M bit unset.\n"); n->myimms.bit.m = 0; /* Unset more bit */ } else s_put(&(n->dbsi), sn); } pkt->imms.byte = n->myimms.byte; length = (j - i) * sizeof(struct ospf_lsa_header) + sizeof(struct ospf_dbdes_packet); op->length = htons(length); DBG("%s: DB_DES (M) prepared for %I.\n", p->name, n->ip); } case NEIGHBOR_LOADING: case NEIGHBOR_FULL: pkt = n->ldbdes; length = ntohs(((struct ospf_packet *) n->ldbdes)->length); if (!length) { OSPF_TRACE(D_PACKETS, "No packet in my buffer for repeating"); ospf_neigh_sm(n, INM_KILLNBR); return; } memcpy(ifa->ip_sk->tbuf, n->ldbdes, length); /* Copy last sent packet again */ ospf_send_to(ifa->ip_sk, n->ip, n->ifa); if(n->myimms.bit.ms) tm_start(n->rxmt_timer, n->ifa->rxmtint); /* Restart timer */ OSPF_TRACE(D_PACKETS, "DB_DES (M) sent to %I via %s.", n->ip, ifa->iface->name); DBG("DB_DES PS=%u, M=%u.", ntohl(pkt->ddseq), pkt->imms.bit.m); if (!n->myimms.bit.ms) { if ((n->myimms.bit.m == 0) && (n->imms.bit.m == 0) && (n->state == NEIGHBOR_EXCHANGE)) { ospf_neigh_sm(n, INM_EXDONE); } } break; default: /* Ignore it */ break; } } static void ospf_dbdes_reqladd(struct ospf_dbdes_packet *ps, struct ospf_neighbor *n) { struct ospf_lsa_header *plsa, lsa; struct top_hash_entry *he, *sn; struct ospf_area *oa = n->ifa->oa; struct top_graph *gr = oa->po->gr; struct ospf_packet *op; int i, j; op = (struct ospf_packet *) ps; plsa = (void *) (ps + 1); j = (ntohs(op->length) - sizeof(struct ospf_dbdes_packet)) / sizeof(struct ospf_lsa_header); for (i = 0; i < j; i++) { ntohlsah(plsa + i, &lsa); if (((he = ospf_hash_find(gr, oa->areaid, lsa.id, lsa.rt, lsa.type)) == NULL) || (lsa_comp(&lsa, &(he->lsa)) == 1)) { /* Is this condition necessary? */ if (ospf_hash_find(n->lsrqh, oa->areaid, lsa.id, lsa.rt, lsa.type) == NULL) { sn = ospf_hash_get(n->lsrqh, oa, lsa.id, lsa.rt, lsa.type); ntohlsah(plsa + i, &(sn->lsa)); s_add_tail(&(n->lsrql), SNODE sn); } } } } void ospf_dbdes_receive(struct ospf_dbdes_packet *ps, struct ospf_iface *ifa, struct ospf_neighbor *n) { struct proto *p = &ifa->oa->po->proto; u32 myrid = p->cf->global->router_id; unsigned int size = ntohs(ps->ospf_packet.length); OSPF_TRACE(D_PACKETS, "Received dbdes from %I via %s.", n->ip, ifa->iface->name); DBG("DB_DES PS=%u, M=%u SIZE=%u.", ntohl(ps->ddseq), ps->imms.bit.m, size); ospf_neigh_sm(n, INM_HELLOREC); switch (n->state) { case NEIGHBOR_DOWN: case NEIGHBOR_ATTEMPT: case NEIGHBOR_2WAY: return; break; case NEIGHBOR_INIT: ospf_neigh_sm(n, INM_2WAYREC); if (n->state != NEIGHBOR_EXSTART) return; case NEIGHBOR_EXSTART: if ((ps->imms.bit.m && ps->imms.bit.ms && ps->imms.bit.i) && (n->rid > myrid) && (size == sizeof(struct ospf_dbdes_packet))) { /* I'm slave! */ n->dds = ntohl(ps->ddseq); n->ddr = ntohl(ps->ddseq); n->options = ps->options; n->myimms.bit.ms = 0; n->imms.byte = ps->imms.byte; OSPF_TRACE(D_PACKETS, "I'm slave to %I.", n->ip); ospf_neigh_sm(n, INM_NEGDONE); ospf_dbdes_send(n); break; } if (((ps->imms.bit.i == 0) && (ps->imms.bit.ms == 0)) && (n->rid < myrid) && (n->dds == ntohl(ps->ddseq))) { /* I'm master! */ n->options = ps->options; n->ddr = ntohl(ps->ddseq) - 1; /* It will be set corectly a few lines down */ n->imms.byte = ps->imms.byte; OSPF_TRACE(D_PACKETS, "I'm master to %I.", n->ip); ospf_neigh_sm(n, INM_NEGDONE); } else { DBG("%s: Nothing happend to %I (imms=%u)\n", p->name, n->ip, ps->imms.byte); break; } case NEIGHBOR_EXCHANGE: if ((ps->imms.byte == n->imms.byte) && (ps->options == n->options) && (ntohl(ps->ddseq) == n->ddr)) { /* Duplicate packet */ OSPF_TRACE(D_PACKETS, "Received duplicate dbdes from %I.", n->ip); if (n->imms.bit.ms == 0) { ospf_dbdes_send(n); } return; } n->ddr = ntohl(ps->ddseq); if (ps->imms.bit.ms != n->imms.bit.ms) /* M/S bit differs */ { OSPF_TRACE(D_PACKETS, "dbdes - sequence mismatch neighbor %I (bit MS)", n->ip); ospf_neigh_sm(n, INM_SEQMIS); break; } if (ps->imms.bit.i) /* I bit is set */ { OSPF_TRACE(D_PACKETS, "dbdes - sequence mismatch neighbor %I (bit I)", n->ip); ospf_neigh_sm(n, INM_SEQMIS); break; } n->imms.byte = ps->imms.byte; if (ps->options != n->options) /* Options differs */ { OSPF_TRACE(D_PACKETS, "dbdes - sequence mismatch neighbor %I (options)", n->ip); ospf_neigh_sm(n, INM_SEQMIS); break; } if (n->myimms.bit.ms) { if (ntohl(ps->ddseq) != n->dds) /* MASTER */ { OSPF_TRACE(D_PACKETS, "dbdes - sequence mismatch neighbor %I (master)", n->ip); ospf_neigh_sm(n, INM_SEQMIS); break; } n->dds++; DBG("Incrementing dds\n"); ospf_dbdes_reqladd(ps, n); if ((n->myimms.bit.m == 0) && (ps->imms.bit.m == 0)) { ospf_neigh_sm(n, INM_EXDONE); } else { ospf_dbdes_send(n); } } else { if (ntohl(ps->ddseq) != (n->dds + 1)) /* SLAVE */ { OSPF_TRACE(D_PACKETS, "dbdes - sequence mismatch neighbor %I (slave)", n->ip); ospf_neigh_sm(n, INM_SEQMIS); break; } n->ddr = ntohl(ps->ddseq); n->dds = ntohl(ps->ddseq); ospf_dbdes_reqladd(ps, n); ospf_dbdes_send(n); } break; case NEIGHBOR_LOADING: case NEIGHBOR_FULL: if ((ps->imms.byte == n->imms.byte) && (ps->options == n->options) && (ntohl(ps->ddseq) == n->ddr)) /* Only duplicate are accepted */ { OSPF_TRACE(D_PACKETS, "Received duplicate dbdes from %I.", n->ip); return; } else { OSPF_TRACE(D_PACKETS, "dbdes - sequence mismatch neighbor %I (full)", n->ip); DBG("PS=%u, DDR=%u, DDS=%u", ntohl(ps->ddseq), n->ddr, n->dds); ospf_neigh_sm(n, INM_SEQMIS); } break; default: bug("Received dbdes from %I in undefined state.", n->ip); } }