bird/proto/ospf/ospf.c
1999-08-09 18:11:51 +00:00

865 lines
19 KiB
C

/*
* BIRD -- OSPF
*
* (c) 1999 Ondrej Filip <feela@network.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#define LOCAL_DEBUG
#include <string.h>
#include "nest/bird.h"
#include "nest/iface.h"
#include "nest/protocol.h"
#include "nest/route.h"
#include "conf/conf.h"
#include "lib/ip.h"
#include "lib/socket.h"
#include "lib/lists.h"
#include "lib/timer.h"
#include "lib/checksum.h"
#include "ospf.h"
/* Try to build neighbor adjacency (if does not exists) */
void
tryadj(struct ospf_neighbor *n, struct proto *p)
{
if(n->state==NEIGHBOR_INIT)
{
DBG("%s: Going to build adjacency.\n", p->name);
n->state=NEIGHBOR_EXSTART;
/* FIXME Go on */
}
}
/* Neighbor is inactive for a long time. Remove it. */
void
neighbor_timer_hook(timer *timer)
{
struct ospf_neighbor *n;
struct ospf_iface *ifa;
struct proto *p;
n=(struct ospf_neighbor *)timer->data;
ifa=n->ifa;
p=(struct proto *)(ifa->proto);
debug("%s: Inactivity timer fired on interface %s for neighbor %u.\n",
p->name, ifa->iface->name, n->rid);
tm_stop(n->inactim);
rfree(n->inactim);
rem_node(NODE n);
mb_free(n);
debug("%s: Deleting neigbor.\n", p->name);
}
void
iface_chstate(struct ospf_iface *ifa, u8 state)
{
struct proto *p;
p=(struct proto *)(ifa->proto);
debug("%s: Changing state of iface: %s from %u into %u.\n",
p->name, ifa->iface->name, ifa->state, state);
ifa->state=state;
}
struct ospf_neighbor *
electbdr(list nl)
{
struct ospf_neighbor *neigh,*n1,*n2;
n1=NULL;
n2=NULL;
WALK_LIST (neigh, nl) /* First try those decl. themselves */
{
if(neigh->state>=NEIGHBOR_2WAY) /* Higher than 2WAY */
if(neigh->priority>0) /* Eligible */
if(neigh->rid!=neigh->dr) /* And not declaring itself DR */
{
if(neigh->rid==neigh->bdr) /* Declaring BDR */
{
if(n1!=NULL)
{
if(neigh->priority>n1->priority) n1=neigh;
else if(neigh->priority==n1->priority)
if(neigh->rid>n1->rid) n1=neigh;
}
else
{
n1=neigh;
}
}
else /* And NOT declaring BDR */
{
if(n2!=NULL)
{
if(neigh->priority>n2->priority) n2=neigh;
else if(neigh->priority==n2->priority)
if(neigh->rid>n2->rid) n2=neigh;
}
else
{
n2=neigh;
}
}
}
}
if(n1==NULL) n1=n2;
return(n1);
}
struct ospf_neighbor *
electdr(list nl)
{
struct ospf_neighbor *neigh,*n;
n=NULL;
WALK_LIST (neigh, nl) /* And now DR */
{
if(neigh->state>=NEIGHBOR_2WAY) /* Higher than 2WAY */
if(neigh->priority>0) /* Eligible */
if(neigh->rid==neigh->dr) /* And declaring itself DR */
{
if(n!=NULL)
{
if(neigh->priority>n->priority) n=neigh;
else if(neigh->priority==n->priority)
if(neigh->rid>n->rid) n=neigh;
}
else
{
n=neigh;
}
}
}
return(n);
}
void
backupseen(struct ospf_iface *ifa)
{
struct proto *p;
struct ospf_neighbor *neigh,*ndr,*nbdr,me;
u32 myid;
p=(struct proto *)(ifa->proto);
tm_stop(ifa->wait_timer);
DBG("%s: Stoping wait timer\n",p->name);
DBG("%s: (B)DR election.\n",p->name);
myid=p->cf->global->router_id;
me.state=NEIGHBOR_2WAY;
me.rid=myid;
me.priority=ifa->priority;
me.dr=ifa->drid;
me.bdr=ifa->bdrid;
add_tail(&ifa->neigh_list, NODE &me);
nbdr=electbdr(ifa->neigh_list);
ndr=electdr(ifa->neigh_list);
if(ndr==NULL) ndr=nbdr;
if(((ifa->drid==myid) && (ndr->rid!=myid))
|| ((ifa->drid!=myid) && (ndr->rid==myid))
|| ((ifa->bdrid==myid) && (nbdr->rid!=myid))
|| ((ifa->bdrid!=myid) && (nbdr->rid==myid)))
{
if(ndr==NULL) ifa->drid=me.dr=0;
else ifa->drid=me.dr=ndr->rid;
if(nbdr==NULL) ifa->bdrid=me.bdr=0;
else ifa->bdrid=me.bdr=nbdr->rid;
nbdr=electbdr(ifa->neigh_list);
ndr=electdr(ifa->neigh_list);
}
if(ndr==NULL) ifa->drid=0;
else ifa->drid=ndr->rid;
if(nbdr==NULL) ifa->bdrid=0;
else ifa->bdrid=me.bdr=nbdr->rid;
DBG("%s: DR=%u, BDR=%u\n",p->name, ifa->drid, ifa->bdrid);
if(myid==ifa->drid) iface_chstate(ifa, OSPF_IS_DR);
else
{
if(myid==ifa->bdrid) iface_chstate(ifa, OSPF_IS_BACKUP);
else iface_chstate(ifa, OSPF_IS_DROTHER);
}
rem_node(NODE &me);
}
void
ospf_hello_rx(struct ospf_hello_packet *ps, struct proto *p,
struct ospf_iface *ifa, int size)
{
char sip[100]; /* FIXME: Should be smaller */
u32 nrid, *pnrid;
struct ospf_neighbor *neigh,*n;
int i,twoway;
nrid=ntohl(((struct ospf_packet *)ps)->routerid);
if(ipa_mklen(ipa_ntoh(ps->netmask))!=ifa->iface->addr->pxlen)
{
ip_ntop(ps->netmask,sip);
log("%s: Bad OSPF packet from %u received: bad netmask %s.",
p->name, nrid, sip);
log("%s: Discarding",p->name);
return;
}
if(ntohs(ps->helloint)!=ifa->helloint)
{
log("%s: Bad OSPF packet from %u received: hello interval mismatch.",
p->name, nrid);
log("%s: Discarding",p->name);
return;
}
if(ntohl(ps->deadint)!=ifa->helloint*ifa->deadc)
{
log("%s: Bad OSPF packet from %u received: dead interval mismatch.",
p->name, nrid);
log("%s: Discarding",p->name);
return;
}
if(ps->options!=ifa->options)
{
log("%s: Bad OSPF packet from %u received: options mismatch.",
p->name, nrid); /* FIXME: This not good */
log("%s: Discarding",p->name);
return;
}
n=NULL;
WALK_LIST (neigh, ifa->neigh_list)
{
if(neigh->rid==nrid)
{
n=neigh;
break;
}
}
if(n==NULL)
{
log("%s: New neighbor found: %u.",p->name,nrid);
n=mb_alloc(p->pool, sizeof(struct ospf_neighbor));
add_tail(&ifa->neigh_list, NODE n);
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);
n->state=NEIGHBOR_INIT;
n->rid=nrid;
n->dr=ntohl(ps->dr);
n->bdr=ntohl(ps->bdr);
n->priority=ps->priority;
n->options=ps->options;
}
tm_start(n->inactim,ifa->deadc*ifa->helloint);
twoway=0;
pnrid=(u32 *)((struct ospf_hello_packet *)(ps+1));
for(i=0;i<size-(sizeof(struct ospf_hello_packet));i++)
{
if(ntohl(*(pnrid+i))==p->cf->global->router_id)
{
twoway=1;
DBG("%s: Twoway received. %u\n", p->name, nrid);
break;
}
}
if(twoway)
{
if(n->state<NEIGHBOR_2WAY) n->state=NEIGHBOR_2WAY;
}
else
{
if(n->state>=NEIGHBOR_2WAY)
{
/* FIXME Delete all learnt */
n->state=NEIGHBOR_INIT;
}
}
/* Check priority change */
if(n->priority!=(n->priority=ps->priority))
{
/* FIXME NeighborChange */;
}
/* Check neighbor's designed router idea */
if((n->rid!=ntohl(ps->dr)) && (ntohl(ps->bdr)==0) &&
(ifa->state==OSPF_IS_WAITING) && (n->state>=NEIGHBOR_2WAY))
{
backupseen(ifa);
}
if((n->rid==ntohl(ps->dr)) && (n->dr!=ntohl(ps->dr)))
{
/* FIXME NeighborChange */;
}
if((n->rid==n->dr) && (n->dr!=ntohl(ps->dr)))
{
/* FIXME NeighborChange */;
}
n->dr=ntohl(ps->dr); /* And update it */
/* Check neighbor's backup designed router idea */
if((n->rid==ntohl(ps->bdr)) && (ifa->state==OSPF_IS_WAITING)
&& (n->state>=NEIGHBOR_2WAY))
{
backupseen(ifa);
}
if((n->rid==ntohl(ps->bdr)) && (n->bdr!=ntohl(ps->bdr)))
{
/* FIXME NeighborChange */;
}
if((n->rid==n->bdr) && (n->bdr!=ntohl(ps->bdr)))
{
/* FIXME NeighborChange */;
}
n->bdr=ntohl(ps->bdr); /* And update it */
switch(ifa->state)
{
case OSPF_IS_DOWN:
die("%s: Iface %s in down state?", p->name, ifa->iface->name);
break;
case OSPF_IS_WAITING:
DBG(p->name);
DBG(": Neighbor? on iface ");
DBG(ifa->iface->name);
DBG("\n");
break;
case OSPF_IS_DROTHER:
if(twoway)
{
if((n->rid==n->dr) || (n->rid==n->bdr)) tryadj(n,p);
else n->state=NEIGHBOR_2WAY;
}
else
{
if(n->state==NEIGHBOR_2WAY) n->state=NEIGHBOR_INIT;
if(n->state>NEIGHBOR_2WAY)
{
/* FIXME Kill adjacency */;
n->state=NEIGHBOR_INIT;
}
}
break;
case OSPF_IS_PTP:
case OSPF_IS_BACKUP:
case OSPF_IS_DR:
if(twoway) tryadj(n,p);
else
{
if(n->state==NEIGHBOR_2WAY) n->state=NEIGHBOR_INIT;
if(n->state>NEIGHBOR_2WAY)
{
/* FIXME Kill adjacency */;
n->state=NEIGHBOR_INIT;
}
}
break;
default:
die("%s: Iface %s in unknown state?",p->name, ifa->iface->name);
break;
}
}
int
ospf_rx_hook(sock *sk, int size)
{
#ifndef IPV6
struct ospf_packet *ps;
struct ospf_iface *ifa;
struct proto *p;
int i;
u8 *pu8;
ifa=(struct ospf_iface *)(sk->data);
p=(struct proto *)(ifa->proto);
DBG(p->name);
DBG(": RX_Hook called on interface ");
DBG(sk->iface->name);
DBG(".\n");
ps = (struct ospf_packet *) ipv4_skip_header(sk->rbuf, &size);
if(ps==NULL)
{
log("%s: Bad packet received: bad IP header", p->name);
log("%s: Discarding",p->name);
return(1);
}
if(size < sizeof(struct ospf_packet))
{
log("%s: Bad packet received: too short (%u bytes)", p->name, size);
log("%s: Discarding",p->name);
return(1);
}
if(ntohs(ps->length) != size)
{
log("%s: Bad packet received: size field does not match", p->name);
log("%s: Discarding",p->name);
return(1);
}
if(ps->version!=OSPF_VERSION)
{
log("%s: Bad packet received: version %u", p->name, ps->version);
log("%s: Discarding",p->name);
return(1);
}
if(!ipsum_verify(ps, 16,(void *)ps+sizeof(struct ospf_packet),
ntohs(ps->length)-sizeof(struct ospf_packet), NULL))
{
log("%s: Bad packet received: bad checksum", p->name);
log("%s: Discarding",p->name);
return(1);
}
/* FIXME: Do authetification */
if(ps->areaid!=ifa->area)
{
log("%s: Bad packet received: other area %ld", p->name, ps->areaid);
log("%s: Discarding",p->name);
return(1);
}
/* Dump packet */
pu8=(u8 *)(sk->rbuf+5*4);
for(i=0;i<ntohs(ps->length);i+=4)
debug("%s: received %u,%u,%u,%u\n",p->name, pu8[i+0], pu8[i+1], pu8[i+2],
pu8[i+3]);
debug("%s: received size: %u\n",p->name,size);
switch(ps->type)
{
case HELLO:
DBG(p->name);
DBG(": Hello received.\n");
ospf_hello_rx((struct ospf_hello_packet *)ps, p, ifa, size);
break;
case DBDES:
break;
case LSREQ:
break;
case LSUPD:
break;
case LSACK:
break;
default:
log("%s: Bad packet received: wrong type %u", p->name, ps->type);
log("%s: Discarding",p->name);
return(1);
};
DBG("\n");
#else
#error RX_Hook does not work for IPv6 now.
#endif
return(1);
}
void
ospf_tx_hook(sock *sk)
{
struct ospf_iface *ifa;
struct proto *p;
ifa=(struct ospf_iface *)(sk->data);
p=(struct proto *)(ifa->proto);
DBG(p->name);
DBG(": TX_Hook called on interface ");
DBG(sk->iface->name);
DBG(".\n");
}
void
ospf_err_hook(sock *sk, int err)
{
struct ospf_iface *ifa;
struct proto *p;
ifa=(struct ospf_iface *)(sk->data);
p=(struct proto *)(ifa->proto);
DBG(p->name);
DBG(": Err_Hook called on interface ");
DBG(sk->iface->name);
DBG(".\n");
}
/* This will change ! */
sock *
ospf_open_socket(struct proto *p, struct ospf_iface *ifa)
{
sock *mcsk;
/* FIXME: No NBMA networks now */
if(ifa->iface->flags & IF_MULTICAST)
{
mcsk=sk_new(p->pool);
mcsk->type=SK_IP_MC;
mcsk->dport=OSPF_PROTO;
mcsk->saddr=AllSPFRouters;
mcsk->daddr=AllSPFRouters;
mcsk->tos=IP_PREC_INTERNET_CONTROL;
mcsk->ttl=1;
mcsk->rx_hook=ospf_rx_hook;
mcsk->tx_hook=ospf_tx_hook;
mcsk->err_hook=ospf_err_hook;
mcsk->iface=ifa->iface;
mcsk->rbsize=ifa->iface->mtu;
mcsk->tbsize=ifa->iface->mtu;
mcsk->data=(void *)ifa;
if(sk_open(mcsk)!=0)
{
DBG(p->name);
DBG(": SK_OPEN: failed\n");
return(NULL);
}
DBG(p->name);
DBG(": SK_OPEN: open\n");
return(mcsk);
}
else return(NULL);
}
/*
* This will later decide, wheter use iface for OSPF or not
* depending on config
*/
int
is_good_iface(struct proto *p, struct iface *iface)
{
if(iface->flags & IF_UP)
{
if(!(iface->flags & IF_IGNORE)) return 1;
}
return 0;
}
/* Of course, it's NOT true now */
int
ospf_iface_clasify(struct iface *ifa)
{
/* FIXME: Latter I'll use config - this is incorrect */
if((ifa->flags & (IF_MULTIACCESS|IF_MULTICAST))==
(IF_MULTIACCESS|IF_MULTICAST))
{
DBG(" OSPF: Clasifying BROADCAST.\n");
return OSPF_IT_BROADCAST;
}
if((ifa->flags & (IF_MULTIACCESS|IF_MULTICAST))==
IF_MULTIACCESS)
{
DBG(" OSPF: Clasifying NBMA.\n");
return OSPF_IT_NBMA;
}
DBG(" OSPF: Clasifying P-T-P.\n");
return OSPF_IT_PTP;
}
void
fill_ospf_pkt_hdr(struct ospf_iface *ifa, void *buf, u8 h_type)
{
struct ospf_packet *pkt;
struct proto *p;
p=(struct proto *)(ifa->proto);
pkt=(struct ospf_packet *)buf;
pkt->version=OSPF_VERSION;
pkt->type=h_type;
pkt->routerid=htonl(p->cf->global->router_id);
pkt->areaid=htonl(ifa->area);
pkt->autype=htons(ifa->autype);
}
void
hello_timer_hook(timer *timer)
{
struct ospf_iface *ifa;
struct ospf_hello_packet *pkt;
struct ospf_packet *op;
struct proto *p;
struct ospf_neighbor *neigh;
u16 length;
u32 *pp;
int i;
ifa=(struct ospf_iface *)timer->data;
p=(struct proto *)(ifa->proto);
debug("%s: Hello 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)
{
/* Now fill ospf_hello header */
pkt=(struct ospf_hello_packet *)(ifa->hello_sk->tbuf);
op=(struct ospf_packet *)pkt;
fill_ospf_pkt_hdr(ifa, pkt, HELLO);
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->drid;
pkt->bdr=ifa->bdrid;
/* Fill all neighbors */
i=0;
pp=(u32 *)(((byte *)pkt)+sizeof(struct ospf_hello_packet));
WALK_LIST (neigh, ifa->neigh_list)
{
*(pp+i)=neigh->rid;
i++;
}
length=sizeof(struct ospf_hello_packet)+i*sizeof(u32);
op->length=ntohs(length);
/* Do authentification */
op->checksum=ipsum_calculate(op,sizeof(struct ospf_packet)-8,
&(pkt->netmask),length-sizeof(struct ospf_packet),NULL);
/* And finally send it :-) */
sk_send(ifa->hello_sk,length);
}
}
void
wait_timer_hook(timer *timer)
{
struct ospf_iface *ifa;
struct proto *p;
ifa=(struct ospf_iface *)timer->data;
p=(struct proto *)(ifa->proto);
debug("%s: Wait timer fired on interface %s.\n",
p->name, ifa->iface->name);
if(ifa->state=OSPF_IS_WAITING) backupseen(ifa);
else die("%s: Wait timer fired I'm not in WAITING state?", p->name);
}
void
ospf_add_timers(struct ospf_iface *ifa, pool *pool, int wait)
{
struct proto *p;
p=(struct proto *)(ifa->proto);
/* Add hello timer */
ifa->hello_timer=tm_new(pool);
ifa->hello_timer->data=ifa;
ifa->hello_timer->randomize=0;
if(ifa->helloint==0) ifa->helloint=HELLOINT_D;
ifa->hello_timer->hook=hello_timer_hook;
ifa->hello_timer->recurrent=ifa->helloint;
tm_start(ifa->hello_timer,ifa->helloint);
DBG("%s: Installing hello timer. (%u)\n", p->name, ifa->helloint);
if((ifa->type!=OSPF_IT_PTP))
{
/* Install wait timer on NOT-PtP interfaces */
ifa->wait_timer=tm_new(pool);
ifa->wait_timer->data=ifa;
ifa->wait_timer->randomize=0;
ifa->wait_timer->hook=wait_timer_hook;
ifa->wait_timer->recurrent=0;
ifa->state=OSPF_IS_WAITING;
tm_start(ifa->wait_timer,(wait!=0 ? wait : WAIT_DMH*ifa->helloint));
DBG("%s: Installing wait timer. (%u)\n", p->name, (wait!=0 ? wait : WAIT_DMH*ifa->helloint));
}
else ifa->state=OSPF_IS_PTP;
}
void
ospf_iface_default(struct ospf_iface *ifa)
{
int i;
ifa->area=0; /* FIXME: Read from config */
ifa->cost=COST_D;
ifa->rxmtint=RXMTINT_D;
ifa->iftransdelay=IFTRANSDELAY_D;
ifa->priority=PRIORITY_D;
ifa->helloint=HELLOINT_D;
ifa->deadc=DEADC_D;
ifa->autype=0;
for(i=0;i<8;i++) ifa->aukey[i]=0;
ifa->options=2;
ifa->drip=ipa_from_u32(0x00000000);
ifa->drid=0;
ifa->bdrip=ipa_from_u32(0x00000000);
ifa->bdrid=0;
ifa->type=ospf_iface_clasify(ifa->iface);
}
struct ospf_iface*
find_iface(struct proto_ospf *p, struct iface *what)
{
struct ospf_iface *i;
WALK_LIST (i, p->iface_list)
if ((i)->iface == what)
return i;
return NULL;
}
void
ospf_if_notify(struct proto *p, unsigned flags, struct iface *iface)
{
struct ospf_iface *ifa;
sock *mcsk;
struct ospf_config *c;
c=(struct ospf_config *)(p->cf);
DBG(" OSPF: If notify called\n");
if (iface->flags & IF_IGNORE)
return;
if((flags & IF_CHANGE_UP) && is_good_iface(p, iface))
{
debug(" OSPF: using interface %s.\n", iface->name);
/* FIXME: Latter I'll use config - this is incorrect */
ifa=mb_alloc(p->pool, sizeof(struct ospf_iface));
ifa->proto=(struct proto_ospf *)p;
ifa->iface=iface;
ospf_iface_default(ifa);
if(ifa->type!=OSPF_IT_NBMA)
{
if((mcsk=ospf_open_socket(p, ifa))!=NULL)
{
ifa->hello_sk=mcsk;
}
else
{
log("%s: Huh? could not open socket on interface %s?", p->name,
iface->name);
mb_free(ifa);
log("%s: Ignoring this interface\n", p->name);
return;
}
/* FIXME: In fail case??? */
init_list(&(ifa->neigh_list));
}
/* FIXME: NBMA? */
/* FIXME: This should read config */
ifa->helloint=0;
ospf_add_timers(ifa,p->pool,0);
add_tail(&((struct proto_ospf *)p)->iface_list, NODE ifa);
}
if(flags & IF_CHANGE_DOWN)
{
if((ifa=find_iface((struct proto_ospf *)p, iface))!=NULL)
{
debug(" OSPF: killing interface %s.\n", iface->name);
/* FIXME: This should delete ifaces */
}
}
if(flags & IF_CHANGE_MTU)
{
if((ifa=find_iface((struct proto_ospf *)p, iface))!=NULL)
{
debug(" OSPF: changing MTU on interface %s.\n", iface->name);
/* FIXME: change MTU */
}
}
}
static int
ospf_start(struct proto *p)
{
DBG(p->name);
DBG(": Start\n");
p->if_notify=ospf_if_notify;
return PS_UP;
}
static void
ospf_dump(struct proto *p)
{
char areastr[20];
struct ospf_config *c = (void *) p->cf;
DBG(p->name);
DBG(": Dump.\n");
debug(" -AreaID: %u\n", c->area );
}
static struct proto *
ospf_init(struct proto_config *c)
{
struct proto *p = proto_new(c, sizeof(struct proto_ospf));
DBG(" OSPF: Init.\n");
p->neigh_notify = NULL;
p->if_notify = NULL;
init_list(&((struct proto_ospf *)p)->iface_list);
return p;
}
static void
ospf_preconfig(struct protocol *p, struct config *c)
{
DBG( " OSPF: preconfig\n" );
}
static void
ospf_postconfig(struct proto_config *c)
{
DBG( " OSPF: postconfig\n" );
}
struct protocol proto_ospf = {
name: "OSPF",
init: ospf_init,
dump: ospf_dump,
start: ospf_start,
preconfig: ospf_preconfig,
postconfig: ospf_postconfig,
};