365 lines
8.1 KiB
C
365 lines
8.1 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"
|
|
|
|
|
|
#ifdef OSPFv2
|
|
struct ospf_hello_packet
|
|
{
|
|
struct ospf_packet ospf_packet;
|
|
ip_addr netmask;
|
|
u16 helloint;
|
|
u8 options;
|
|
u8 priority;
|
|
u32 deadint;
|
|
u32 dr;
|
|
u32 bdr;
|
|
};
|
|
#endif
|
|
|
|
|
|
#ifdef OSPFv3
|
|
struct ospf_hello_packet
|
|
{
|
|
struct ospf_packet ospf_packet;
|
|
u32 iface_id;
|
|
u8 priority;
|
|
u8 options3;
|
|
u8 options2;
|
|
u8 options;
|
|
u16 helloint;
|
|
u16 deadint;
|
|
u32 dr;
|
|
u32 bdr;
|
|
};
|
|
#endif
|
|
|
|
|
|
void
|
|
ospf_hello_receive(struct ospf_packet *ps_i, struct ospf_iface *ifa,
|
|
struct ospf_neighbor *n, ip_addr faddr)
|
|
{
|
|
struct proto_ospf *po = ifa->oa->po;
|
|
struct proto *p = &po->proto;
|
|
char *beg = "OSPF: Bad HELLO packet from ";
|
|
unsigned int size, i, twoway, oldpriority, eligible, peers;
|
|
u32 olddr, oldbdr, oldiface_id, tmp;
|
|
u32 *pnrid;
|
|
|
|
size = ntohs(ps_i->length);
|
|
if (size < sizeof(struct ospf_hello_packet))
|
|
{
|
|
log(L_ERR "%s%I - too short (%u B)", beg, faddr, size);
|
|
return;
|
|
}
|
|
|
|
struct ospf_hello_packet *ps = (void *) ps_i;
|
|
|
|
OSPF_TRACE(D_PACKETS, "HELLO packet received from %I via %s%s", faddr,
|
|
(ifa->type == OSPF_IT_VLINK ? "vlink-" : ""), ifa->iface->name);
|
|
|
|
#ifdef OSPFv2
|
|
ip_addr mask = ps->netmask;
|
|
ipa_ntoh(mask);
|
|
if ((ifa->type != OSPF_IT_VLINK) &&
|
|
(ifa->type != OSPF_IT_PTP) &&
|
|
!ipa_equal(mask, ipa_mkmask(ifa->addr->pxlen)))
|
|
{
|
|
log(L_ERR "%s%I - netmask mismatch (%I)", beg, faddr, mask);
|
|
return;
|
|
}
|
|
#endif
|
|
|
|
tmp = ntohs(ps->helloint);
|
|
if (tmp != ifa->helloint)
|
|
{
|
|
log(L_ERR "%s%I - hello interval mismatch (%d)", beg, faddr, tmp);
|
|
return;
|
|
}
|
|
|
|
#ifdef OSPFv2
|
|
tmp = ntohl(ps->deadint);
|
|
#else /* OSPFv3 */
|
|
tmp = ntohs(ps->deadint);
|
|
#endif
|
|
if (tmp != ifa->dead)
|
|
{
|
|
log(L_ERR "%s%I - dead interval mismatch (%d)", beg, faddr, tmp);
|
|
return;
|
|
}
|
|
|
|
tmp = !(ps->options & OPT_E);
|
|
if (tmp != ifa->oa->stub)
|
|
{
|
|
log(L_ERR "%s%I - stub area flag mismatch (%d)", beg, faddr, tmp);
|
|
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 = ntohl(ps->dr);
|
|
n->bdr = ntohl(ps->bdr);
|
|
n->priority = ps->priority;
|
|
#ifdef OSPFv3
|
|
n->iface_id = ntohl(ps->iface_id);
|
|
#endif
|
|
}
|
|
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]) == po->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;
|
|
oldbdr = n->bdr;
|
|
oldpriority = n->priority;
|
|
#ifdef OSPFv3
|
|
oldiface_id = n->iface_id;
|
|
#endif
|
|
|
|
n->dr = ntohl(ps->dr);
|
|
n->bdr = ntohl(ps->bdr);
|
|
n->priority = ps->priority;
|
|
#ifdef OSPFv3
|
|
n->iface_id = ntohl(ps->iface_id);
|
|
#endif
|
|
|
|
|
|
/* Check priority change */
|
|
if (n->state >= NEIGHBOR_2WAY)
|
|
{
|
|
#ifdef OSPFv2
|
|
u32 neigh = ipa_to_u32(n->ip);
|
|
#else /* OSPFv3 */
|
|
u32 neigh = n->rid;
|
|
#endif
|
|
|
|
if (n->priority != oldpriority)
|
|
ospf_iface_sm(ifa, ISM_NEICH);
|
|
|
|
#ifdef OSPFv3
|
|
if (n->iface_id != oldiface_id)
|
|
ospf_iface_sm(ifa, ISM_NEICH);
|
|
#endif
|
|
|
|
/* Neighbor is declaring itself ad DR and there is no BDR */
|
|
if ((n->dr == neigh) && (n->bdr == 0)
|
|
&& (n->state != NEIGHBOR_FULL))
|
|
ospf_iface_sm(ifa, ISM_BACKS);
|
|
|
|
/* Neighbor is declaring itself as BDR */
|
|
if ((n->bdr == neigh) && (n->state != NEIGHBOR_FULL))
|
|
ospf_iface_sm(ifa, ISM_BACKS);
|
|
|
|
/* Neighbor is newly declaring itself as DR or BDR */
|
|
if (((n->dr == neigh) && (n->dr != olddr))
|
|
|| ((n->bdr == neigh) && (n->bdr != oldbdr)))
|
|
ospf_iface_sm(ifa, ISM_NEICH);
|
|
|
|
/* Neighbor is no more declaring itself as DR or BDR */
|
|
if (((olddr == neigh) && (n->dr != olddr))
|
|
|| ((oldbdr == neigh) && (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 */
|
|
pkt = ospf_tx_buffer(ifa);
|
|
op = &pkt->ospf_packet;
|
|
|
|
/* Now fill ospf_hello header */
|
|
ospf_pkt_fill_hdr(ifa, pkt, HELLO_P);
|
|
|
|
#ifdef OSPFv2
|
|
pkt->netmask = ipa_mkmask(ifa->addr->pxlen);
|
|
ipa_hton(pkt->netmask);
|
|
if ((ifa->type == OSPF_IT_VLINK) || (ifa->type == OSPF_IT_PTP))
|
|
pkt->netmask = IPA_NONE;
|
|
#endif
|
|
|
|
pkt->helloint = ntohs(ifa->helloint);
|
|
pkt->priority = ifa->priority;
|
|
|
|
#ifdef OSPFv3
|
|
pkt->iface_id = htonl(ifa->iface->index);
|
|
|
|
pkt->options3 = ifa->oa->options >> 16;
|
|
pkt->options2 = ifa->oa->options >> 8;
|
|
#endif
|
|
pkt->options = ifa->oa->options;
|
|
|
|
#ifdef OSPFv2
|
|
pkt->deadint = htonl(ifa->dead);
|
|
pkt->dr = htonl(ipa_to_u32(ifa->drip));
|
|
pkt->bdr = htonl(ipa_to_u32(ifa->bdrip));
|
|
#else /* OSPFv3 */
|
|
pkt->deadint = htons(ifa->dead);
|
|
pkt->dr = htonl(ifa->drid);
|
|
pkt->bdr = htonl(ifa->bdrid);
|
|
#endif
|
|
|
|
/* 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, dirn->ip);
|
|
}
|
|
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, nb->ip);
|
|
}
|
|
}
|
|
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, n1->ip);
|
|
}
|
|
}
|
|
}
|
|
break;
|
|
case OSPF_IT_VLINK:
|
|
ospf_send_to(ifa, ifa->vip);
|
|
break;
|
|
default:
|
|
ospf_send_to(ifa, AllSPFRouters);
|
|
}
|
|
|
|
OSPF_TRACE(D_PACKETS, "HELLO packet sent via %s%s",
|
|
(ifa->type == OSPF_IT_VLINK ? "vlink-" : ""), ifa->iface->name);
|
|
}
|