bird/proto/ospf/hello.c
2004-05-31 13:22:49 +00:00

365 lines
8.5 KiB
C

/*
* BIRD -- OSPF
*
* (c) 1999 - 2000 Ondrej Filip <feela@network.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#include "ospf.h"
#include <sys/socket.h>
#include "lib/sysio.h"
void
install_inactim(struct ospf_neighbor *n)
{
struct proto *p;
struct ospf_iface *ifa;
ifa=n->ifa;
p=(struct proto *)(ifa->proto);
if(n->inactim==NULL)
{
n->inactim=tm_new(p->pool);
n->inactim->data=n;
n->inactim->randomize=0;
n->inactim->hook=neighbor_timer_hook;
n->inactim->recurrent=0;
DBG("%s: Installing inactivity timer.\n", p->name);
}
}
void
restart_inactim(struct ospf_neighbor *n)
{
tm_start(n->inactim,n->ifa->deadc*n->ifa->helloint);
}
void
restart_hellotim(struct ospf_iface *ifa)
{
tm_start(ifa->hello_timer,ifa->helloint);
}
void
restart_polltim(struct ospf_iface *ifa)
{
if(ifa->poll_timer)
tm_start(ifa->poll_timer,ifa->pollint);
}
void
restart_waittim(struct ospf_iface *ifa)
{
tm_start(ifa->wait_timer,ifa->waitint);
}
void
ospf_hello_rx(struct ospf_hello_packet *ps, struct proto *p,
struct ospf_iface *ifa, int size, ip_addr faddr)
{
u32 nrid, *pnrid;
struct ospf_neighbor *neigh,*n;
u8 i,twoway,oldpriority;
ip_addr olddr,oldbdr;
ip_addr mask;
char *beg=": Bad OSPF hello packet from ", *rec=" received: ";
int eligible=0;
nrid=ntohl(((struct ospf_packet *)ps)->routerid);
OSPF_TRACE(D_PACKETS, "Received hello from %I via %s",faddr,ifa->iface->name);
mask=ps->netmask;
ipa_ntoh(mask);
if((unsigned)ipa_mklen(mask)!=ifa->iface->addr->pxlen)
{
log("%s%s%I%sbad netmask %I.", p->name, beg, nrid, rec,
mask);
return;
}
if(ntohs(ps->helloint)!=ifa->helloint)
{
log("%s%s%I%shello interval mismatch.", p->name, beg, faddr, rec);
return;
}
if(ntohl(ps->deadint)!=ifa->helloint*ifa->deadc)
{
log("%s%s%I%sdead interval mismatch.", p->name, beg, faddr, rec);
return;
}
if(ps->options!=ifa->options)
{
log("%s%s%I%soptions mismatch.", p->name, beg, faddr, rec);
return;
}
if((n=find_neigh(ifa, nrid))==NULL)
{
if((ifa->type==OSPF_IT_NBMA))
{
struct nbma_node *nn;
int found=0;
WALK_LIST(nn,ifa->nbma_list)
{
if(ipa_compare(faddr,nn->ip)==0)
{
found=1;
break;
}
}
if((found==0)&&(ifa->strictnbma))
{
log("%s: Ignoring new neighbor: %I on %s.", p->name, faddr,
ifa->iface->name);
return;
}
if(found)
{
eligible=nn->eligible;
if(((ps->priority==0)&&eligible)||((ps->priority>0)&&(eligible==0)))
{
log("%s: Eligibility mismatch for neighbor: %I on %s", p->name,
faddr, ifa->iface->name);
return;
}
}
}
OSPF_TRACE(D_EVENTS, "New neighbor found: %I on %s.", faddr,
ifa->iface->name);
n=mb_allocz(p->pool, sizeof(struct ospf_neighbor));
add_tail(&ifa->neigh_list, NODE n);
n->rid=nrid;
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;
n->ifa=ifa;
n->adj=0;
n->ldbdes=mb_alloc(p->pool, ifa->iface->mtu);
n->state=NEIGHBOR_DOWN;
install_inactim(n);
n->rxmt_timer=tm_new(p->pool);
n->rxmt_timer->data=n;
n->rxmt_timer->randomize=0;
n->rxmt_timer->hook=rxmt_timer_hook;
n->rxmt_timer->recurrent=ifa->rxmtint;
DBG("%s: Installing rxmt timer.\n", p->name);
n->lsrr_timer=tm_new(p->pool);
n->lsrr_timer->data=n;
n->lsrr_timer->randomize=0;
n->lsrr_timer->hook=lsrr_timer_hook;
n->lsrr_timer->recurrent=ifa->rxmtint;
DBG("%s: Installing lsrr timer.\n", p->name);
init_list(&n->ackl);
n->ackd_timer=tm_new(p->pool);
n->ackd_timer->data=n;
n->ackd_timer->randomize=0;
n->ackd_timer->hook=ackd_timer_hook;
n->ackd_timer->recurrent=ifa->rxmtint/2;
DBG("%s: Installing ackd timer.\n", p->name);
}
ospf_neigh_sm(n, INM_HELLOREC);
pnrid=(u32 *)((struct ospf_hello_packet *)(ps+1));
twoway=0;
for(i=0;i<size-(sizeof(struct ospf_hello_packet));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_int_sm(ifa, ISM_NEICH);
/* Router is declaring itself ad DR and there is no BDR */
if((ipa_compare(n->ip,n->dr)==0) && (ipa_to_u32(n->bdr)==0)
&& (n->state!=NEIGHBOR_FULL))
ospf_int_sm(ifa, ISM_BACKS);
/* Neighbor is declaring itself as BDR */
if((ipa_compare(n->ip,n->bdr)==0) && (n->state!=NEIGHBOR_FULL))
ospf_int_sm(ifa, ISM_BACKS);
/* Neighbor is newly declaring itself as DR or BDR */
if(((ipa_compare(n->ip,n->dr)==0) && (ipa_compare(n->dr,olddr)!=0))
|| ((ipa_compare(n->ip,n->bdr)==0) && (ipa_compare(n->bdr,oldbdr)!=0)))
ospf_int_sm(ifa, ISM_NEICH);
/* Neighbor is no more declaring itself as DR or BDR */
if(((ipa_compare(n->ip,olddr)==0) && (ipa_compare(n->dr,olddr)!=0))
|| ((ipa_compare(n->ip,oldbdr)==0) && (ipa_compare(n->bdr,oldbdr)!=0)))
ospf_int_sm(ifa, ISM_NEICH);
}
if(ifa->type!=OSPF_IT_NBMA)
{
if((ifa->priority==0)&&(n->priority>0)) hello_send(NULL,0, n);
}
ospf_neigh_sm(n, INM_HELLOREC);
}
void
poll_timer_hook(timer *timer)
{
hello_send(timer,1, NULL);
}
void
hello_timer_hook(timer *timer)
{
hello_send(timer,0, NULL);
}
void
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;
u16 length;
u32 *pp;
u8 i;
if(timer==NULL) ifa=dirn->ifa;
else ifa=(struct ospf_iface *)timer->data;
if(ifa->stub) return; /* Don't send any packet on stub iface */
p=(struct proto *)(ifa->proto);
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)
{
pkt=(struct ospf_hello_packet *)(ifa->hello_sk->tbuf);
}
else
{
pkt=(struct ospf_hello_packet *)(ifa->ip_sk->tbuf);
}
/* Now fill ospf_hello header */
op=(struct ospf_packet *)pkt;
fill_ospf_pkt_hdr(ifa, pkt, HELLO_P);
pkt->netmask=ipa_mkmask(ifa->iface->addr->pxlen);
ipa_hton(pkt->netmask);
pkt->helloint=ntohs(ifa->helloint);
pkt->options=ifa->options;
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)
{
*(pp+i)=htonl(neigh->rid);
i++;
}
length=sizeof(struct ospf_hello_packet)+i*sizeof(u32);
op->length=htons(length);
ospf_pkt_finalize(ifa, op);
/* And finally send it :-) */
if(ifa->type!=OSPF_IT_NBMA)
{
sk_send(ifa->hello_sk,length);
}
else /* NBMA */
{
struct ospf_neighbor *n1;
struct nbma_node *nb;
int send;
if(timer==NULL) /* Response to received hello */
{
sk_send_to(ifa->ip_sk, length, dirn->ip, OSPF_PROTO);
}
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_compare(nb->ip,n1->ip)==0)
{
send=0;
break;
}
}
if((poll==1)&&(send))
{
if(toall||(meeli&&nb->eligible))
sk_send_to(ifa->ip_sk, length, nb->ip, OSPF_PROTO);
}
}
if(poll==0)
{
WALK_LIST(n1,ifa->neigh_list)
{
if(toall||(n1->rid==ifa->drid)||(n1->rid==ifa->bdrid)||
(meeli&&(n1->priority>0)))
sk_send_to(ifa->ip_sk, length, n1->ip, OSPF_PROTO);
}
}
}
}
OSPF_TRACE(D_PACKETS, "Hello sent via %s",ifa->iface->name);
}
void
wait_timer_hook(timer *timer)
{
struct ospf_iface *ifa;
struct proto *p;
ifa=(struct ospf_iface *)timer->data;
p=(struct proto *)(ifa->proto);
OSPF_TRACE(D_EVENTS, "Wait timer fired on interface %s.",
ifa->iface->name);
ospf_int_sm(ifa, ISM_WAITF);
}