proto/ospf/lsack.c

   1 /*
   2  *      BIRD -- OSPF
   3  *
   4  *      (c) 2000--2004 Ondrej Filip <feela@network.cz>
   5  *      (c) 2009--2014 Ondrej Zajicek <santiago@crfreenet.org>
   6  *      (c) 2009--2014 CZ.NIC z.s.p.o.
   7  *
   8  *      Can be freely distributed and used under the terms of the GNU GPL.
   9  */
  10
  11 #include "ospf.h"
  12
  13
  14 /*
  15 struct ospf_lsack_packet
  16 {
  17   struct ospf_packet hdr;
  18   // union ospf_auth auth;
  19
  20   struct ospf_lsa_header lsas[];
  21 };
  22 */
  23
  24 struct lsa_node
  25 {
  26   node n;
  27   struct ospf_lsa_header lsa;
  28 };
  29
  30
  31 static inline void
  32 ospf_lsack_body(struct ospf_proto *p, struct ospf_packet *pkt,
  33                 struct ospf_lsa_header **body, uint *count)
  34 {
  35   uint plen = ntohs(pkt->length);
  36   uint hlen = ospf_pkt_hdrlen(p);
  37
  38   *body = ((void *) pkt) + hlen;
  39   *count = (plen - hlen) / sizeof(struct ospf_lsa_header);
  40 }
  41
  42 static void
  43 ospf_dump_lsack(struct ospf_proto *p, struct ospf_packet *pkt)
  44 {
  45   struct ospf_lsa_header *lsas;
  46   uint i, lsa_count;
  47
  48   ASSERT(pkt->type == LSACK_P);
  49   ospf_dump_common(p, pkt);
  50
  51   ospf_lsack_body(p, pkt, &lsas, &lsa_count);
  52   for (i = 0; i < lsa_count; i++)
  53     ospf_dump_lsahdr(p, lsas + i);
  54 }
  55
  56
  57 void
  58 ospf_enqueue_lsack(struct ospf_neighbor *n, struct ospf_lsa_header *h_n, int queue)
  59 {
  60   /* Note that h_n is in network endianity */
  61   struct lsa_node *no = mb_alloc(n->pool, sizeof(struct lsa_node));
  62   memcpy(&no->lsa, h_n, sizeof(struct ospf_lsa_header));
  63   add_tail(&n->ackl[queue], NODE no);
  64   DBG("Adding %s ack for %R, ID: %R, RT: %R, Type: %u\n",
  65       (queue == ACKL_DIRECT) ? "direct" : "delayed",
  66       n->rid, ntohl(h_n->id), ntohl(h_n->rt), h_n->type);
  67 }
  68
  69 void
  70 ospf_reset_lsack_queue(struct ospf_neighbor *n)
  71 {
  72   struct lsa_node *no;
  73
  74   WALK_LIST_FIRST(no, n->ackl[ACKL_DELAY])
  75   {
  76     rem_node(NODE no);
  77     mb_free(no);
  78   }
  79 }
  80
  81 static inline void
  82 ospf_send_lsack_(struct ospf_proto *p, struct ospf_neighbor *n, int queue)
  83 {
  84   struct ospf_iface *ifa = n->ifa;
  85   struct ospf_lsa_header *lsas;
  86   struct ospf_packet *pkt;
  87   struct lsa_node *no;
  88   uint i, lsa_max, length;
  89
  90   /* RFC 2328 13.5 */
  91
  92   pkt = ospf_tx_buffer(ifa);
  93   ospf_pkt_fill_hdr(ifa, pkt, LSACK_P);
  94   ospf_lsack_body(p, pkt, &lsas, &lsa_max);
  95
  96   for (i = 0; i < lsa_max && !EMPTY_LIST(n->ackl[queue]); i++)
  97   {
  98     no = (struct lsa_node *) HEAD(n->ackl[queue]);
  99     memcpy(&lsas[i], &no->lsa, sizeof(struct ospf_lsa_header));
 100     DBG("Iter %u ID: %R, RT: %R, Type: %04x\n",
 101         i, ntohl(lsas[i].id), ntohl(lsas[i].rt), lsas[i].type);
 102     rem_node(NODE no);
 103     mb_free(no);
 104   }
 105
 106   length = ospf_pkt_hdrlen(p) + i * sizeof(struct ospf_lsa_header);
 107   pkt->length = htons(length);
 108
 109   OSPF_PACKET(ospf_dump_lsack, pkt, "LSACK packet sent via %s", ifa->ifname);
 110
 111   if (ifa->type == OSPF_IT_BCAST)
 112   {
 113     if ((ifa->state == OSPF_IS_DR) || (ifa->state == OSPF_IS_BACKUP))
 114       ospf_send_to_all(ifa);
 115     else
 116       ospf_send_to_des(ifa);
 117   }
 118   else
 119     ospf_send_to_agt(ifa, NEIGHBOR_EXCHANGE);
 120 }
 121
 122 void
 123 ospf_send_lsack(struct ospf_proto *p, struct ospf_neighbor *n, int queue)
 124 {
 125   while (!EMPTY_LIST(n->ackl[queue]))
 126     ospf_send_lsack_(p, n, queue);
 127 }
 128
 129 void
 130 ospf_receive_lsack(struct ospf_packet *pkt, struct ospf_iface *ifa,
 131                    struct ospf_neighbor *n)
 132 {
 133   struct ospf_proto *p = ifa->oa->po;
 134   struct ospf_lsa_header lsa, *lsas;
 135   struct top_hash_entry *ret, *en;
 136   uint i, lsa_count;
 137   u32 lsa_type, lsa_domain;
 138
 139   /* RFC 2328 13.7 */
 140
 141   /* No need to check length, lsack has only basic header */
 142
 143   OSPF_PACKET(ospf_dump_lsack, pkt, "LSACK packet received from nbr %R on %s", n->rid, ifa->ifname);
 144
 145   if (n->state < NEIGHBOR_EXCHANGE)
 146   {
 147     OSPF_TRACE(D_PACKETS, "LSACK packet ignored - lesser state than Exchange");
 148     return;
 149   }
 150
 151   ospf_neigh_sm(n, INM_HELLOREC);       /* Not in RFC */
 152
 153   ospf_lsack_body(p, pkt, &lsas, &lsa_count);
 154   for (i = 0; i < lsa_count; i++)
 155   {
 156     lsa_ntoh_hdr(&lsas[i], &lsa);
 157     lsa_get_type_domain(&lsa, n->ifa, &lsa_type, &lsa_domain);
 158
 159     ret = ospf_hash_find(n->lsrth, lsa_domain, lsa.id, lsa.rt, lsa_type);
 160     if (!ret)
 161       continue;
 162
 163     if (lsa_comp(&lsa, &ret->lsa) != CMP_SAME)
 164     {
 165       OSPF_TRACE(D_PACKETS, "Strange LSACK from %I", n->ip);
 166       OSPF_TRACE(D_PACKETS, "Type: %04x, Id: %R, Rt: %R",
 167                  lsa_type, lsa.id, lsa.rt);
 168       OSPF_TRACE(D_PACKETS, "I have: Age: %4u, Seq: %08x, Sum: %04x",
 169                  ret->lsa.age, ret->lsa.sn, ret->lsa.checksum);
 170       OSPF_TRACE(D_PACKETS, "He has: Age: %4u, Seq: %08x, Sum: %04x",
 171                  lsa.age, lsa.sn, lsa.checksum);
 172       continue;
 173     }
 174
 175     en = ospf_hash_find_entry(p->gr, ret);
 176     if (en)
 177       en->ret_count--;
 178
 179     DBG("Deleting LSA (Type: %04x Id: %R Rt: %R) from lsrtl for neighbor %R\n",
 180         lsa_type, lsa.id, lsa.rt, n->rid);
 181     s_rem_node(SNODE ret);
 182     ospf_hash_delete(n->lsrth, ret);
 183   }
 184 }