bird/proto/ospf/hello.c
Ondrej Filip 86c84d76b7 Huge OSPF database redesign. Since now, all LSAs of all areas
are in single database. This avoids duplication of external LSAs and
fixes bug in external LSA distribution.
2004-07-15 16:37:52 +00:00

287 lines
7.2 KiB
C

/*
* 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"
void
ospf_hello_receive(struct ospf_hello_packet *ps,
struct ospf_iface *ifa, struct ospf_neighbor *n, ip_addr faddr)
{
u32 *pnrid;
ip_addr olddr, oldbdr;
ip_addr mask;
char *beg = "Bad OSPF hello packet from ", *rec = " received: ";
struct proto *p = (struct proto *) ifa->oa->po;
unsigned int size = ntohs(ps->ospf_packet.length), i, twoway, oldpriority, eligible = 0, peers;
OSPF_TRACE(D_PACKETS, "Received hello from %I via %s%s", faddr,
(ifa->type == OSPF_IT_VLINK ? "vlink-" : ""), ifa->iface->name);
mask = ps->netmask;
ipa_ntoh(mask);
if ((ifa->type != OSPF_IT_VLINK) &&
((unsigned) ipa_mklen(mask) != ifa->iface->addr->pxlen))
{
log(L_ERR "%s%I%sbad netmask %I.", beg, faddr, rec, mask);
return;
}
if (ntohs(ps->helloint) != ifa->helloint)
{
log(L_WARN "%s%I%shello interval mismatch (%d).", beg, faddr, rec,
ntohs(ps->helloint));
return;
}
if (ntohl(ps->deadint) != ifa->helloint * ifa->deadc)
{
log(L_ERR "%s%I%sdead interval mismatch (%d).", beg, faddr, rec,
ntohl(ps->deadint));
return;
}
if (ps->options != ifa->oa->opt.byte)
{
log(L_ERR "%s%I%soptions mismatch (0x%x).", beg, faddr, rec, ps->options);
return;
}
if (!n)
{
if ((ifa->type == OSPF_IT_NBMA))
{
struct nbma_node *nn;
int found = 0;
WALK_LIST(nn, ifa->nbma_list)
{
if (ipa_equal(faddr, nn->ip))
{
found = 1;
break;
}
}
if ((found == 0) && (ifa->strictnbma))
{
log(L_WARN "Ignoring new neighbor: %I on %s.", faddr,
ifa->iface->name);
return;
}
if (found)
{
eligible = nn->eligible;
if (((ps->priority == 0) && eligible)
|| ((ps->priority > 0) && (eligible == 0)))
{
log(L_ERR "Eligibility mismatch for neighbor: %I on %s",
faddr, ifa->iface->name);
return;
}
}
}
OSPF_TRACE(D_EVENTS, "New neighbor found: %I on %s.", faddr,
ifa->iface->name);
n = ospf_neighbor_new(ifa);
n->rid = ntohl(((struct ospf_packet *) ps)->routerid);
n->ip = faddr;
n->dr = ps->dr;
ipa_ntoh(n->dr);
n->bdr = ps->bdr;
ipa_ntoh(n->bdr);
n->priority = ps->priority;
n->options = ps->options;
}
ospf_neigh_sm(n, INM_HELLOREC);
pnrid = (u32 *) ((struct ospf_hello_packet *) (ps + 1));
peers = (size - sizeof(struct ospf_hello_packet))/ sizeof(u32);
twoway = 0;
for (i = 0; i < peers; i++)
{
if (ntohl(*(pnrid + i)) == p->cf->global->router_id)
{
DBG("%s: Twoway received from %I\n", p->name, faddr);
ospf_neigh_sm(n, INM_2WAYREC);
twoway = 1;
break;
}
}
if (!twoway)
ospf_neigh_sm(n, INM_1WAYREC);
olddr = n->dr;
n->dr = ipa_ntoh(ps->dr);
oldbdr = n->bdr;
n->bdr = ipa_ntoh(ps->bdr);
oldpriority = n->priority;
n->priority = ps->priority;
/* Check priority change */
if (n->state >= NEIGHBOR_2WAY)
{
if (n->priority != oldpriority)
ospf_iface_sm(ifa, ISM_NEICH);
/* Router is declaring itself ad DR and there is no BDR */
if (ipa_equal(n->ip, n->dr) && (ipa_to_u32(n->bdr) == 0)
&& (n->state != NEIGHBOR_FULL))
ospf_iface_sm(ifa, ISM_BACKS);
/* Neighbor is declaring itself as BDR */
if (ipa_equal(n->ip, n->bdr) && (n->state != NEIGHBOR_FULL))
ospf_iface_sm(ifa, ISM_BACKS);
/* Neighbor is newly declaring itself as DR or BDR */
if ((ipa_equal(n->ip, n->dr) && (!ipa_equal(n->dr, olddr)))
|| (ipa_equal(n->ip, n->bdr) && (!ipa_equal(n->bdr, oldbdr))))
ospf_iface_sm(ifa, ISM_NEICH);
/* Neighbor is no more declaring itself as DR or BDR */
if ((ipa_equal(n->ip, olddr) && (!ipa_equal(n->dr, olddr)))
|| (ipa_equal(n->ip, oldbdr) && (!ipa_equal(n->bdr, oldbdr))))
ospf_iface_sm(ifa, ISM_NEICH);
}
if (ifa->type == OSPF_IT_NBMA)
{
if ((ifa->priority == 0) && (n->priority > 0))
ospf_hello_send(NULL, 0, n);
}
ospf_neigh_sm(n, INM_HELLOREC);
}
void
ospf_hello_send(timer * timer, int poll, struct ospf_neighbor *dirn)
{
struct ospf_iface *ifa;
struct ospf_hello_packet *pkt;
struct ospf_packet *op;
struct proto *p;
struct ospf_neighbor *neigh, *n1;
u16 length;
u32 *pp;
int i, send;
struct nbma_node *nb;
if (timer == NULL)
ifa = dirn->ifa;
else
ifa = (struct ospf_iface *) timer->data;
if (ifa->state == OSPF_IS_DOWN)
return;
if (ifa->stub)
return; /* Don't send any packet on stub iface */
p = (struct proto *) (ifa->oa->po);
DBG("%s: Hello/Poll timer fired on interface %s.\n",
p->name, ifa->iface->name);
/* Now we should send a hello packet */
/* First a common packet header */
if ((ifa->type == OSPF_IT_NBMA) || (ifa->type == OSPF_IT_VLINK))
{
pkt = (struct ospf_hello_packet *) (ifa->ip_sk->tbuf);
}
else
{
pkt = (struct ospf_hello_packet *) (ifa->hello_sk->tbuf);
}
/* Now fill ospf_hello header */
op = (struct ospf_packet *) pkt;
ospf_pkt_fill_hdr(ifa, pkt, HELLO_P);
pkt->netmask = ipa_mkmask(ifa->iface->addr->pxlen);
ipa_hton(pkt->netmask);
if (ifa->type == OSPF_IT_VLINK) pkt->netmask = IPA_NONE;
pkt->helloint = ntohs(ifa->helloint);
pkt->options = ifa->oa->opt.byte;
pkt->priority = ifa->priority;
pkt->deadint = htonl(ifa->deadc * ifa->helloint);
pkt->dr = ifa->drip;
ipa_hton(pkt->dr);
pkt->bdr = ifa->bdrip;
ipa_hton(pkt->bdr);
/* Fill all neighbors */
i = 0;
pp = (u32 *) (((u8 *) pkt) + sizeof(struct ospf_hello_packet));
WALK_LIST(neigh, ifa->neigh_list)
{
if ((i+1) * sizeof(u32) + sizeof(struct ospf_hello_packet) > ospf_pkt_maxsize(ifa))
{
OSPF_TRACE(D_PACKETS, "Too many neighbors on the interface!");
break;
}
*(pp + i) = htonl(neigh->rid);
i++;
}
length = sizeof(struct ospf_hello_packet) + i * sizeof(u32);
op->length = htons(length);
switch(ifa->type)
{
case OSPF_IT_NBMA:
if (timer == NULL) /* Response to received hello */
{
ospf_send_to(ifa->ip_sk, dirn->ip, ifa);
}
else
{
int toall = 0;
int meeli = 0;
if (ifa->state > OSPF_IS_DROTHER)
toall = 1;
if (ifa->priority > 0)
meeli = 1;
WALK_LIST(nb, ifa->nbma_list)
{
send = 1;
WALK_LIST(n1, ifa->neigh_list)
{
if (ipa_equal(nb->ip, n1->ip))
{
send = 0;
break;
}
}
if ((poll == 1) && (send))
{
if (toall || (meeli && nb->eligible))
ospf_send_to(ifa->ip_sk, nb->ip, ifa);
}
}
if (poll == 0)
{
WALK_LIST(n1, ifa->neigh_list)
{
if (toall || (n1->rid == ifa->drid) || (n1->rid == ifa->bdrid) ||
(meeli && (n1->priority > 0)))
ospf_send_to(ifa->ip_sk, n1->ip, ifa);
}
}
}
break;
case OSPF_IT_VLINK:
ospf_send_to(ifa->ip_sk, ifa->vip, ifa);
break;
default:
ospf_send_to(ifa->hello_sk, IPA_NONE, ifa);
}
OSPF_TRACE(D_PACKETS, "Hello sent via %s%s",
(ifa->type == OSPF_IT_VLINK ? "vlink-" : ""), ifa->iface->name);
}