bird/proto/ospf/lsupd.c
2004-06-06 18:45:08 +00:00

574 lines
14 KiB
C

/*
* 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"
/**
* ospf_lsupd_flood - send received or generated lsa to the neighbors
* @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)
* @po: actual instance of OSPF protocol
* @iff: interface which received this LSA (or NULL if LSA is generated)
* @oa: ospf_area which is the LSA generated for
* @rtl: add this LSA into retransmission list
*
* return value - was the LSA flooded back?
*/
int
ospf_lsupd_flood(struct ospf_neighbor *n, struct ospf_lsa_header *hn,
struct ospf_lsa_header *hh, struct ospf_iface *iff,
struct ospf_area *oa, int rtl)
{
struct ospf_iface *ifa;
struct ospf_neighbor *nn;
struct top_hash_entry *en;
struct proto_ospf *po = oa->po;
struct proto *p = &po->proto;
int ret, retval = 0;
/* pg 148 */
WALK_LIST(NODE ifa, po->iface_list)
{
if (ifa->stub)
continue;
if (hh->type == LSA_T_EXT)
{
if (ifa->type == OSPF_IT_VLINK)
continue;
if (ifa->oa->stub)
continue;
}
else
{
if (oa->areaid == BACKBONE)
{
if ((ifa->type != OSPF_IT_VLINK) && (ifa->oa != oa))
continue;
}
else
{
if (ifa->oa != oa)
continue;
}
}
ret = 0;
WALK_LIST(NODE nn, ifa->neigh_list)
{
if (nn->state < NEIGHBOR_EXCHANGE)
continue;
if (nn->state < NEIGHBOR_FULL)
{
if ((en = ospf_hash_find_header(nn->lsrqh, hh)) != NULL)
{
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 %I\n", nn->rid);
ospf_hash_delete(nn->lsrqh, en);
if (EMPTY_SLIST(nn->lsrql))
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 %I\n", nn->rid);
ospf_hash_delete(nn->lsrqh, en);
if (EMPTY_SLIST(nn->lsrql))
ospf_neigh_sm(nn, INM_LOADDONE);
break;
default:
bug("Bug in lsa_comp?");
}
}
}
if (nn == n)
continue;
if (rtl)
{
if ((en = ospf_hash_find_header(nn->lsrth, hh)) == NULL)
{
en = ospf_hash_get_header(nn->lsrth, 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 LSA lsrt RT: %I, Id: %I, Type: %u for n: %I\n",
en->lsa.rt, en->lsa.id, en->lsa.type, nn->ip);
}
else
{
if ((en = ospf_hash_find_header(nn->lsrth, hh)) != NULL)
{
s_rem_node(SNODE en);
if (en->lsa_body != NULL)
mb_free(en->lsa_body);
en->lsa_body = NULL;
ospf_hash_delete(nn->lsrth, en);
}
}
ret = 1;
}
if (ret == 0)
continue; /* pg 150 (2) */
if (ifa == iff)
{
if ((n->rid == iff->drid) || n->rid == iff->bdrid)
continue; /* pg 150 (3) */
if (iff->state == OSPF_IS_BACKUP)
continue; /* pg 150 (4) */
retval = 1;
}
{
sock *sk;
u16 len, age;
struct ospf_lsupd_packet *pk;
struct ospf_packet *op;
struct ospf_lsa_header *lh;
if (ifa->type == OSPF_IT_NBMA)
sk = ifa->ip_sk;
else
sk = ifa->hello_sk; /* FIXME is this true for PTP? */
pk = (struct ospf_lsupd_packet *) sk->tbuf;
op = (struct ospf_packet *) sk->tbuf;
fill_ospf_pkt_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(oa->gr, hh);
htonlsab(en->lsa_body, help, hh->type, 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_pkt_finalize(ifa, op);
OSPF_TRACE(D_PACKETS, "LS upd flooded via %s", ifa->iface->name);
if (ifa->type == OSPF_IT_NBMA)
{
if ((ifa->state == OSPF_IS_BACKUP) || (ifa->state == OSPF_IS_DR))
sk_send_to_agt(sk, len, ifa, NEIGHBOR_EXCHANGE);
else
sk_send_to_bdr(sk, len, ifa);
}
else
{
if ((ifa->state == OSPF_IS_BACKUP) || (ifa->state == OSPF_IS_DR) ||
(ifa->type == OSPF_IT_PTP))
sk_send_to(sk, len, AllSPFRouters, OSPF_PROTO);
else
sk_send_to(sk, len, AllDRouters, OSPF_PROTO);
}
}
}
return retval;
}
void /* I send all I received in LSREQ */
ospf_lsupd_send_list(struct ospf_neighbor *n, list * l)
{
struct l_lsr_head *llsh;
u16 len;
u32 lsano;
struct top_hash_entry *en;
struct ospf_lsupd_packet *pk;
struct ospf_packet *op;
struct proto *p = &n->ifa->oa->po->proto;
void *pktpos;
if (EMPTY_LIST(*l))
return;
pk = (struct ospf_lsupd_packet *) n->ifa->ip_sk->tbuf;
op = (struct ospf_packet *) n->ifa->ip_sk->tbuf;
DBG("LSupd: 1st packet\n");
fill_ospf_pkt_hdr(n->ifa, pk, LSUPD_P);
len = SIPH + sizeof(struct ospf_lsupd_packet);
lsano = 0;
pktpos = (pk + 1);
WALK_LIST(llsh, *l)
{
if ((en = ospf_hash_find(n->ifa->oa->gr, llsh->lsh.id, llsh->lsh.rt,
llsh->lsh.type)) == NULL)
continue; /* Probably flushed LSA */
DBG("Sending ID=%I, Type=%u, RT=%I Sn: 0x%x Age: %u\n",
llsh->lsh.id, llsh->lsh.type, llsh->lsh.rt, en->lsa.sn, en->lsa.age);
if (((u32) (len + en->lsa.length)) > n->ifa->iface->mtu)
{
pk->lsano = htonl(lsano);
op->length = htons(len - SIPH);
ospf_pkt_finalize(n->ifa, op);
sk_send_to(n->ifa->ip_sk, len - SIPH, n->ip, OSPF_PROTO);
OSPF_TRACE(D_PACKETS, "LS upd sent to %I (%d LSAs)", n->ip, lsano);
DBG("LSupd: next packet\n");
fill_ospf_pkt_hdr(n->ifa, pk, LSUPD_P);
len = SIPH + sizeof(struct ospf_lsupd_packet);
lsano = 0;
pktpos = (pk + 1);
}
htonlsah(&(en->lsa), pktpos);
pktpos = pktpos + sizeof(struct ospf_lsa_header);
htonlsab(en->lsa_body, pktpos, en->lsa.type, en->lsa.length
- sizeof(struct ospf_lsa_header));
pktpos = pktpos + en->lsa.length - sizeof(struct ospf_lsa_header);
len += en->lsa.length;
lsano++;
}
if (lsano > 0)
{
pk->lsano = htonl(lsano);
op->length = htons(len - SIPH);
ospf_pkt_finalize(n->ifa, op);
OSPF_TRACE(D_PACKETS, "LS upd sent to %I (%d LSAs)", n->ip, lsano);
sk_send_to(n->ifa->ip_sk, len - SIPH, n->ip, OSPF_PROTO);
}
}
void
ospf_lsupd_receive(struct ospf_lsupd_packet *ps,
struct ospf_iface *ifa, u16 size)
{
u32 area, nrid;
struct ospf_neighbor *n, *ntmp;
struct ospf_lsa_header *lsa;
struct ospf_area *oa;
struct proto_ospf *po = ifa->proto;
struct proto *p = (struct proto *) po;
u8 i;
int sendreq = 1;
nrid = ntohl(ps->ospf_packet.routerid);
if ((n = find_neigh(ifa, nrid)) == NULL)
{
OSPF_TRACE(D_PACKETS, "Received lsupd from unknown neighbor! (%I)", nrid);
return;
}
if (n->state < NEIGHBOR_EXCHANGE)
{
OSPF_TRACE(D_PACKETS,
"Received lsupd in lesser state than EXCHANGE from (%I)",
n->ip);
return;
}
if (size <=
(sizeof(struct ospf_lsupd_packet) + sizeof(struct ospf_lsa_header)))
{
log(L_WARN "Received lsupd from %I is too short!", n->ip);
return;
}
OSPF_TRACE(D_PACKETS, "Received LS upd from %I", n->ip);
ospf_neigh_sm(n, INM_HELLOREC); /* Questionable */
lsa = (struct ospf_lsa_header *) (ps + 1);
area = htonl(ps->ospf_packet.areaid);
oa = ospf_find_area((struct proto_ospf *) p, area);
for (i = 0; i < ntohl(ps->lsano); i++,
lsa = (struct ospf_lsa_header *) (((u8 *) lsa) + ntohs(lsa->length)))
{
struct ospf_lsa_header lsatmp;
struct top_hash_entry *lsadb;
int diff = ((u8 *) lsa) - ((u8 *) ps);
u16 chsum, lenn = ntohs(lsa->length);
if (((diff + sizeof(struct ospf_lsa_header)) >= size)
|| ((lenn + diff) > size))
{
log(L_WARN "Received lsupd from %I is too short!", n->ip);
ospf_neigh_sm(n, INM_BADLSREQ);
break;
}
if ((lenn <= sizeof(struct ospf_lsa_header))
|| (lenn != (4 * (lenn / 4))))
{
log(L_WARN "Received LSA from %I with bad length", n->ip);
ospf_neigh_sm(n, INM_BADLSREQ);
break;
}
/* pg 143 (1) */
chsum = lsa->checksum;
if (chsum != lsasum_check(lsa, NULL))
{
log(L_WARN "Received bad lsa checksum from %I", n->ip);
continue;
}
/* pg 143 (2) */
if ((lsa->type < LSA_T_RT) || (lsa->type > LSA_T_EXT))
{
log(L_WARN "Unknown LSA type from %I", n->ip);
continue;
}
/* pg 143 (3) */
if ((lsa->type == LSA_T_EXT) && oa->stub)
{
log(L_WARN "Received External LSA in stub area from %I", n->ip);
continue;
}
ntohlsah(lsa, &lsatmp);
DBG("Update Type: %u ID: %I RT: %I, Sn: 0x%08x Age: %u, Sum: %u\n",
lsatmp.type, lsatmp.id, lsatmp.rt, lsatmp.sn, lsatmp.age,
lsatmp.checksum);
lsadb = ospf_hash_find_header(oa->gr, &lsatmp);
#ifdef LOCAL_DEBUG
if (lsadb)
DBG("I have Type: %u ID: %I RT: %I, 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(oa))
{
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;
void *body;
struct ospf_iface *nifa;
int self = (lsatmp.rt == p->cf->global->router_id);
DBG("PG143(5): Received LSA is newer\n");
/* pg 145 (5f) - premature aging of self originated lsa */
if ((!self) && (lsatmp.type == LSA_T_NET))
{
WALK_LIST(nifa, po->iface_list)
{
if (ipa_compare(nifa->iface->addr->ip, ipa_from_u32(lsatmp.id)) ==
0)
{
self = 1;
break;
}
}
}
if (self)
{
struct top_hash_entry *en;
if ((lsatmp.age == LSA_MAXAGE) && (lsatmp.sn == LSA_MAXSEQNO))
{
ospf_lsack_enqueue(n, lsa, ACKL_DIRECT);
continue;
}
lsatmp.age = LSA_MAXAGE;
lsatmp.sn = LSA_MAXSEQNO;
lsa->age = htons(LSA_MAXAGE);
lsa->sn = htonl(LSA_MAXSEQNO);
OSPF_TRACE(D_EVENTS, "Premature aging self originated lsa.");
OSPF_TRACE(D_EVENTS, "Type: %d, Id: %I, Rt: %I", lsatmp.type,
lsatmp.id, lsatmp.rt);
lsasum_check(lsa, (lsa + 1)); /* It also calculates chsum! */
lsatmp.checksum = ntohs(lsa->checksum);
ospf_lsupd_flood(NULL, lsa, &lsatmp, NULL, oa, 0);
if (en = ospf_hash_find_header(oa->gr, &lsatmp))
{
ospf_lsupd_flood(NULL, NULL, &en->lsa, NULL, oa, 1);
}
continue;
}
/* pg 144 (5a) */
if (lsadb && ((now - lsadb->inst_t) <= MINLSARRIVAL)) /* FIXME: test for flooding? */
{
DBG("I got it in less that MINLSARRIVAL\n");
sendreq = 0;
continue;
}
if (ospf_lsupd_flood(n, lsa, &lsatmp, ifa, ifa->oa, 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);
}
/* Remove old from all ret lists */
/* pg 144 (5c) */
if (lsadb)
WALK_LIST(NODE ift, po->iface_list)
WALK_LIST(NODE ntmp, ift->neigh_list)
{
struct top_hash_entry *en;
if (ntmp->state > NEIGHBOR_EXSTART)
if ((en = ospf_hash_find_header(ntmp->lsrth, &lsadb->lsa)) != NULL)
{
s_rem_node(SNODE en);
if (en->lsa_body != NULL)
mb_free(en->lsa_body);
en->lsa_body = NULL;
ospf_hash_delete(ntmp->lsrth, en);
}
}
if ((lsatmp.age == LSA_MAXAGE) && (lsatmp.sn == LSA_MAXSEQNO)
&& lsadb && can_flush_lsa(oa))
{
flush_lsa(lsadb, oa);
schedule_rtcalc(po);
continue;
} /* FIXME lsack? */
/* pg 144 (5d) */
body =
mb_alloc(p->pool, lsatmp.length - sizeof(struct ospf_lsa_header));
ntohlsab(lsa + 1, body, lsatmp.type,
lsatmp.length - sizeof(struct ospf_lsa_header));
lsadb = lsa_install_new(&lsatmp, body, oa);
DBG("New LSA installed in DB\n");
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->lsa)) != NULL)
{
/* pg145 (7a) */
s_rem_node(SNODE en);
if (en->lsa_body != NULL)
mb_free(en->lsa_body);
en->lsa_body = NULL;
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 top_hash_entry *en, struct ospf_area *oa)
{
struct ospf_lsa_header *lsa = &en->lsa;
struct proto_ospf *po = oa->po;
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: %d, Id: %I, Rt: %I", lsa->type,
lsa->id, lsa->rt);
ospf_lsupd_flood(NULL, NULL, lsa, NULL, oa, 0);
}