bird/proto/ospf/rt.c

178 lines
3.7 KiB
C
Raw Normal View History

/*
* BIRD -- OSPF
*
* (c) 2000 Ondrej Filip <feela@network.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#include "ospf.h"
void
ospf_rt_spfa(struct ospf_area *oa, struct proto *p)
{
2000-04-27 04:16:36 +08:00
struct top_hash_entry *en, *nx;
u32 i,*rts;
2000-04-27 04:16:36 +08:00
struct ospf_lsa_rt *rt;
struct ospf_lsa_rt_link *rtl;
rta a0,*a;
/*
* First of all, mark all vertices as they are not in SPF
* Maybe I can join this work with Aging of structure
* FIXME look at it
*/
WALK_SLIST(SNODE en, oa->lsal)
{
en->color=OUTSPF;
en->dist=LSINFINITY;
}
init_list(&oa->cand); /* Empty list of candidates */
oa->trcap=0;
oa->rt->dist=0;
oa->rt->color=CANDIDATE;
add_head(&oa->cand, &en->cn);
while(!EMPTY_LIST(oa->cand))
{
struct top_hash_entry *act,*tmp;
node *n;
struct ospf_lsa_net *net;
n=HEAD(oa->cand);
act=SKIP_BACK(struct top_hash_entry, cn, n);
rem_node(n);
act->color=INSPF;
switch(act->lsa.type)
{
case LSA_T_RT:
rt=(struct ospf_lsa_rt *)act->lsa_body;
if((rt->VEB)&(1>>LSA_RT_V)) oa->trcap=1;
rtl=(struct ospf_lsa_rt_link *)(rt+1);
for(i=0;rt->links;i++)
{
tmp=NULL;
switch((rtl+i)->type)
{
case LSART_STUB:
case LSART_VLNK:
continue;
break;
case LSART_NET:
tmp=ospf_hash_find(oa->gr,rtl->data,rtl->id,LSA_T_RT);
break;
case LSART_PTP:
tmp=ospf_hash_find(oa->gr,rtl->data,rtl->id,LSA_T_NET);
break;
default:
log("Unknown link type in router lsa.\n");
break;
}
add_cand(&oa->cand,tmp,act,act->dist+rtl->metric);
}
break;
case LSA_T_NET:
net=(struct ospf_lsa_net *)act->lsa_body;
rts=(u32 *)(net+1);
for(i=0;i<(act->lsa.length-sizeof(struct ospf_lsa_header)-
sizeof(struct ospf_lsa_net))/sizeof(u32);i++)
{
tmp=ospf_hash_find(oa->gr, *rts, *rts, LSA_T_RT);
add_cand(&oa->cand,tmp,act,act->dist);
}
break;
}
2000-04-29 23:57:14 +08:00
/* FIXME Now modify rt for this entry */
}
2000-04-27 04:16:36 +08:00
/* Now calculate routes to stub networks */
WALK_SLIST_DELSAFE(SNODE en, SNODE nx, oa->lsal)
{
if((en->lsa.type==LSA_T_RT)||(en->lsa.type==LSA_T_NET))
{
if(en->dist==LSINFINITY)
{
s_rem_node(SNODE en);
/* FIXME Remove from routing table! */
mb_free(en->lsa_body);
ospf_hash_delete(oa->gr, en);
}
if(en->lsa.type==LSA_T_NET)
{
rt=(struct ospf_lsa_rt *)en->lsa_body;
if((rt->VEB)&(1>>LSA_RT_V)) oa->trcap=1;
rtl=(struct ospf_lsa_rt_link *)(rt+1);
for(i=0;rt->links;i++)
{
if((rtl+i)->type==LSART_STUB)
{
/* Check destination and so on (pg 166) */
}
}
}
}
}
}
void
2000-04-29 23:57:14 +08:00
add_cand(list *l, struct top_hash_entry *en, struct top_hash_entry *par,
u16 dist)
{
node *prev,*n;
int flag=0;
struct top_hash_entry *act;
if(en==NULL) return;
if(en->lsa.age==LSA_MAXAGE) return;
/* FIXME Does it have link back? Test it! */
if(en->color==INSPF) return;
if(dist>=en->dist) return;
/*
* FIXME The line above is not a bug, but we don't support
* multiple next hops. I'll start as soon as nest will
*/
en->nh=calc_next_hop(par);
if(en->color==CANDIDATE) /* We found shorter path */
{
rem_node(&en->cn);
}
en->dist=dist;
en->color=CANDIDATE;
prev=NULL;
WALK_LIST(n,*l)
{
act=SKIP_BACK(struct top_hash_entry, cn, n);
if((act->dist>dist)||
((act->dist==dist)&&(act->lsa.type==LSA_T_NET)))
{
if(prev==NULL) add_head(l,&en->cn);
else insert_node(&en->cn,prev);
break;
}
prev=n;
}
/* FIXME Some VLINK staff should be here */
}
2000-04-29 23:57:14 +08:00
struct top_hash_entry *
calc_next_hop(struct top_hash_entry *par)
2000-04-29 23:57:14 +08:00
{
if(par->nh==NULL)
{
if(par->lsa.type!=LSA_T_RT) return NULL;
}
return par;
2000-04-29 23:57:14 +08:00
}