bird/proto/rip/rip.c
Martin Mares 7dc4827c96 Added everything protocols need to know about multiple routing tables,
i.e. struct proto now contains field 'table' pointing to routing table
the protocol is attached to. Use this instead of &master_table.

Modified all protocols except the kernel syncer to use this field.
1999-03-26 21:50:43 +00:00

635 lines
16 KiB
C

/*
* Rest in pieces - RIP protocol
*
* Copyright (c) 1998 Pavel Machek <pavel@ucw.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#define LOCAL_DEBUG
#include <string.h>
#include <stdlib.h>
#include "nest/bird.h"
#include "nest/iface.h"
#include "nest/protocol.h"
#include "nest/route.h"
#include "lib/socket.h"
#include "lib/resource.h"
#include "lib/lists.h"
#include "lib/timer.h"
#include "rip.h"
#define P ((struct rip_proto *) p)
#define P_CF ((struct rip_proto_config *)p->cf)
#define E ((struct rip_entry *) e)
static void
rip_reply(struct proto *p)
{
#if 0
P->listen->tbuf = "ACK!";
sk_send_to( P->listen, 5, P->listen->faddr, P->listen->fport );
#endif
}
#define P_NAME p->name
/*
* Output processing
*/
static void
rip_tx_err( sock *s, int err )
{
struct rip_connection *c = s->data;
struct proto *p = c->proto;
log( L_ERR "Unexpected error at rip transmit: %m" );
}
static void
rip_tx( sock *s )
{
struct rip_interface *rif = s->data;
struct rip_connection *c = rif->busy;
struct proto *p = c->proto;
struct rip_packet *packet = (void *) s->tbuf;
int i;
do {
if (c->done) {
DBG( "Looks like I'm" );
c->rif->busy = NULL;
rem_node(NODE c);
mb_free(c);
DBG( " done\n" );
return;
}
if (c->done) {
DBG( "looks like I'm done!\n" );
return;
}
DBG( "Preparing packet to send: " );
packet->heading.command = RIPCMD_RESPONSE;
packet->heading.version = RIP_V2;
packet->heading.unused = 0;
i = 0;
FIB_ITERATE_START(&P->rtable, &c->iter, z) {
struct rip_entry *e = (struct rip_entry *) z;
DBG( "." );
packet->block[i].family = htons( 2 ); /* AF_INET */
packet->block[i].tag = htons( 0 ); /* FIXME: What should I set it to? */
packet->block[i].network = e->n.prefix;
packet->block[i].netmask = ipa_mkmask( e->n.pxlen );
packet->block[i].nexthop = IPA_NONE; /* FIXME: How should I set it? My own IP address? */
packet->block[i].metric = htonl( 1+ (e->metric?:1) ); /* FIXME: is this right? I already ++ metric at input side */
if (ipa_equal(e->whotoldme, s->daddr)) {
DBG( "(split horizont)" );
/* FIXME: should we do it in all cases? */
packet->block[i].metric = P_CF->infinity;
}
ipa_hton( packet->block[i].network );
ipa_hton( packet->block[i].netmask );
ipa_hton( packet->block[i].nexthop );
if (i++ == 25) {
FIB_ITERATE_PUT(&c->iter, z);
goto break_loop;
}
} FIB_ITERATE_END(z);
c->done = 1;
break_loop:
DBG( ", sending %d blocks, ", i );
if (ipa_nonzero(c->daddr))
i = sk_send_to( s, sizeof( struct rip_packet_heading ) + i*sizeof( struct rip_block ), c->daddr, c->dport );
else
i = sk_send( s, sizeof( struct rip_packet_heading ) + i*sizeof( struct rip_block ) );
DBG( "it wants more\n" );
} while (i>0);
if (i<0) rip_tx_err( s, i );
DBG( "blocked\n" );
}
static void
rip_sendto( struct proto *p, ip_addr daddr, int dport, struct rip_interface *rif )
{
struct iface *iface = rif->iface;
struct rip_connection *c = mb_alloc( p->pool, sizeof( struct rip_connection ));
static int num = 0;
if (rif->busy) {
log (L_WARN "Interface %s is much too slow, dropping request", iface->name);
return;
}
rif->busy = c;
c->addr = daddr;
c->proto = p;
c->num = num++;
c->rif = rif;
c->dport = dport;
c->daddr = daddr;
if (c->rif->sock->data != rif)
bug("not enough send magic");
#if 0
if (sk_open(c->send)<0) {
log( L_ERR "Could not open socket for data send to %I:%d on %s", daddr, dport, rif->iface->name );
return;
}
#endif
c->done = 0;
fit_init( &c->iter, &P->rtable );
add_head( &P->connections, NODE c );
debug( "Sending my routing table to %I:%d on %s\n", daddr, dport, rif->iface->name );
rip_tx(c->rif->sock);
}
static struct rip_interface*
find_interface(struct proto *p, struct iface *what)
{
struct rip_interface *i;
WALK_LIST (i, P->interfaces)
if (i->iface == what)
return i;
return NULL;
}
/*
* Input processing
*/
static int
process_authentication( struct proto *p, struct rip_block *block )
{
/* FIXME: Should do md5 authentication */
return 0;
}
/* Let main routing table know about our new entry */
static void
advertise_entry( struct proto *p, struct rip_block *b, ip_addr whotoldme )
{
rta *a, A;
rte *r;
net *n;
neighbor *neighbor;
struct rip_interface *rif;
bzero(&A, sizeof(A));
A.proto = p;
A.source = RTS_RIP;
A.scope = SCOPE_UNIVERSE;
A.cast = RTC_UNICAST;
A.dest = RTD_ROUTER;
A.tos = 0;
A.flags = 0;
A.gw = ipa_nonzero(b->nexthop) ? b->nexthop : whotoldme;
A.from = whotoldme;
/* FIXME: Check if destination looks valid - ie not net 0 or 127 */
neighbor = neigh_find( p, &A.gw, 0 );
if (!neighbor) {
log( L_ERR "%I asked me to route %I/%I using not-neighbor %I.", A.from, b->network, b->netmask, A.gw );
return;
}
A.iface = neighbor->iface;
if (!(rif = neighbor->data)) {
rif = neighbor->data = find_interface(p, A.iface);
}
if (!rif) {
bug("Route packet using unknown interface? No.");
return;
}
/* set to: interface of nexthop */
a = rta_lookup(&A);
if (!ipa_equal( ipa_mkmask(ipa_mklen(b->netmask)), b->netmask)) {
log( L_ERR "%I asked me to route %I/%I, but that is not valid netmask.", A.from, b->network, b->netmask );
return;
}
n = net_get( p->table, 0, b->network, ipa_mklen( b->netmask ));
r = rte_get_temp(a);
r->u.rip.metric = ntohl(b->metric) + rif->metric;
if (r->u.rip.metric > P_CF->infinity) r->u.rip.metric = P_CF->infinity;
r->u.rip.tag = ntohl(b->tag);
r->net = n;
r->pflags = 0; /* Here go my flags */
rte_update( n, p, r );
DBG( "done\n" );
}
static void
process_block( struct proto *p, struct rip_block *block, ip_addr whotoldme )
{
struct rip_entry *e;
int metric = ntohl( block->metric );
ip_addr network = block->network;
CHK_MAGIC;
if ((!metric) || (metric > P_CF->infinity)) {
log( L_WARN "Got metric %d from %I", metric, whotoldme );
return;
}
debug( "block: %I tells me: %I/%I available, metric %d... ", whotoldme, network, block->netmask, metric );
advertise_entry( p, block, whotoldme );
}
#define BAD( x ) { log( L_WARN "RIP/%s: " x, P_NAME ); return 1; }
static int
rip_process_packet( struct proto *p, struct rip_packet *packet, int num, ip_addr whotoldme, int port )
{
int i;
int native_class = 0;
switch( packet->heading.version ) {
case RIP_V1: DBG( "Rip1: " ); break;
case RIP_V2: DBG( "Rip2: " ); break;
default: BAD( "Unknown version" );
}
switch( packet->heading.command ) {
case RIPCMD_REQUEST: DBG( "Asked to send my routing table\n" );
/* FIXME: should have configurable: ignore always, honour to neighbours, honour always. FIXME: use one global socket for these. FIXME: synchronization - if two ask me at same time */
rip_sendto( p, whotoldme, port, NULL ); /* no broadcast */
break;
case RIPCMD_RESPONSE: DBG( "*** Rtable from %I\n", whotoldme );
if (port != P_CF->port) {
log( L_ERR "%I send me routing info from port %d", whotoldme, port );
#if 0
return 0;
#else
log( L_ERR "...ignoring" );
#endif
}
if (!neigh_find( p, &whotoldme, 0 )) {
log( L_ERR "%I send me routing info but he is not my neighbour", whotoldme );
return 0;
}
/* FIXME: Should check if it is not my own packet */
for (i=0; i<num; i++) {
struct rip_block *block = &packet->block[i];
if (block->family == 0xffff)
if (!i) {
if (process_authentication(p, block))
BAD( "Authentication failed" );
} else BAD( "Authentication is not the first!" );
ipa_ntoh( block->network );
ipa_ntoh( block->netmask );
ipa_ntoh( block->nexthop );
if (packet->heading.version == RIP_V1) {
block->netmask = block->network; /* MJ: why are macros like this?! */
ipa_class_mask( block->netmask );
}
process_block( p, block, whotoldme );
}
break;
case RIPCMD_TRACEON:
case RIPCMD_TRACEOFF: BAD( "I was asked for traceon/traceoff" );
case 5: BAD( "Some Sun extension around here" );
default: BAD( "Unknown command" );
}
rip_reply(p);
return 0;
}
static int
rip_rx(sock *s, int size)
{
struct rip_interface *i = s->data;
struct proto *p = i->proto;
int num;
CHK_MAGIC;
DBG( "RIP: message came: %d bytes\n", size );
size -= sizeof( struct rip_packet_heading );
if (size < 0) BAD( "Too small packet" );
if (size % sizeof( struct rip_block )) BAD( "Odd sized packet" );
num = size / sizeof( struct rip_block );
if (num>25) BAD( "Too many blocks" );
rip_process_packet( p, (struct rip_packet *) s->rbuf, num, s->faddr, s->fport );
return 1;
}
/*
* Interface to rest of bird
*/
static void
rip_dump_entry( struct rip_entry *e )
{
debug( "%I told me %d/%d ago: to %I/%d go via %I, metric %d ",
e->whotoldme, e->updated-now, e->changed-now, e->n.prefix, e->n.pxlen, e->nexthop, e->metric );
if (e->flags & RIP_F_EXTERNAL) debug( "[external]" );
debug( "\n" );
}
static void
rip_timer(timer *t)
{
struct proto *p = t->data;
struct rip_entry *e, *et;
CHK_MAGIC;
DBG( "RIP: tick tock\n" );
WALK_LIST_DELSAFE( e, et, P->garbage ) {
rte *rte;
rte = SKIP_BACK( struct rte, u.rip.garbage, e );
DBG( "Garbage: " ); rte_dump( rte );
if (now - rte->lastmod > P_CF->garbage_time) {
debug( "RIP: entry is too old: " ); rte_dump( rte );
rte_discard(rte);
}
}
DBG( "RIP: Broadcasting routing tables\n" );
{
struct rip_interface *rif;
WALK_LIST( rif, P->interfaces ) {
struct iface *iface = rif->iface;
if (!iface) continue;
if (rif->patt->mode == IM_QUIET) continue;
if (!(iface->flags & IF_UP)) continue;
if (iface->flags & (IF_IGNORE | IF_LOOPBACK)) continue;
rip_sendto( p, IPA_NONE, 0, rif );
}
}
DBG( "RIP: tick tock done\n" );
}
static int
rip_start(struct proto *p)
{
struct rip_interface *rif;
DBG( "RIP: starting instance...\n" );
P->magic = RIP_MAGIC;
fib_init( &P->rtable, p->pool, sizeof( struct rip_entry ), 0, NULL );
init_list( &P->connections );
init_list( &P->garbage );
init_list( &P->interfaces );
P->timer = tm_new( p->pool );
P->timer->data = p;
P->timer->randomize = 5;
P->timer->recurrent = P_CF->period;
P->timer->hook = rip_timer;
tm_start( P->timer, 5 );
rif = new_iface(p, NULL, 0); /* Initialize dummy interface */
add_head( &P->interfaces, NODE rif );
CHK_MAGIC;
rip_init_instance(p);
DBG( "RIP: ...done\n");
return PS_UP;
}
static struct proto *
rip_init(struct proto_config *cfg)
{
struct proto *p = proto_new(cfg, sizeof(struct rip_proto));
return p;
}
static void
rip_dump(struct proto *p)
{
int i;
node *w, *e;
struct rip_interface *rif;
i = 0;
CHK_MAGIC;
WALK_LIST( w, P->connections ) {
struct rip_connection *n = (void *) w;
debug( "RIP: connection #%d: %I\n", n->num, n->addr );
}
i = 0;
FIB_WALK( &P->rtable, e ) {
debug( "RIP: entry #%d: ", i++ );
rip_dump_entry( E );
} FIB_WALK_END;
i = 0;
WALK_LIST( rif, P->interfaces ) {
debug( "RIP: interface #%d: %s, %I, busy = %x\n", i++, rif->iface?rif->iface->name:"(dummy)", rif->sock->daddr, rif->busy );
}
}
static int
rip_want_this_if(struct rip_interface *iface)
{
return 1;
}
static void
kill_iface(struct proto *p, struct rip_interface *i)
{
DBG( "RIP: Interface %s disappeared\n", i->iface->name);
rfree(i->sock);
mb_free(i);
}
/*
* new maybe null if we are creating initial send socket
*/
struct rip_interface *
new_iface(struct proto *p, struct iface *new, unsigned long flags)
{
struct rip_interface *rif;
int want_multicast;
rif = mb_alloc(p->pool, sizeof( struct rip_interface ));
rif->iface = new;
rif->proto = p;
rif->busy = NULL;
want_multicast = 0 && (flags & IF_MULTICAST);
/* FIXME: should have config option to disable this one */
/* FIXME: lookup multicasts over unnumbered links */
rif->sock = sk_new( p->pool );
rif->sock->type = want_multicast?SK_UDP_MC:SK_UDP;
rif->sock->sport = P_CF->port;
rif->sock->rx_hook = rip_rx;
rif->sock->data = rif;
rif->sock->rbsize = 10240;
rif->sock->iface = new; /* Automagically works for dummy interface */
rif->sock->tbuf = mb_alloc( p->pool, sizeof( struct rip_packet ));
rif->sock->tx_hook = rip_tx;
rif->sock->err_hook = rip_tx_err;
rif->sock->daddr = IPA_NONE;
rif->sock->dport = P_CF->port;
rif->sock->ttl = 1; /* FIXME: care must be taken not to send requested responses from this socket */
if (want_multicast)
rif->sock->daddr = ipa_from_u32(0x7f000001); /* FIXME: must lookup address in rfc's */
if (flags & IF_BROADCAST)
rif->sock->daddr = new->brd;
if (flags & IF_UNNUMBERED)
rif->sock->daddr = new->opposite;
if (!ipa_nonzero(rif->sock->daddr))
log( L_WARN "RIP: interface %s is too strange for me", rif->iface ? rif->iface->name : "(dummy)" );
if (sk_open(rif->sock)<0)
die( "RIP/%s: could not listen on %s", P_NAME, rif->iface ? rif->iface->name : "(dummy)" );
/* FIXME: Should not be fatal, since the interface might have gone */
return rif;
}
static void
rip_if_notify(struct proto *p, unsigned c, struct iface *new, struct iface *old)
{
DBG( "RIP: if notify\n" );
if (old) {
struct rip_interface *i;
i = find_interface(p, old);
if (i) {
rem_node(NODE i);
kill_iface(p, i);
}
}
if (new) {
struct rip_interface *rif;
struct iface_patt *k = iface_patt_match(&P_CF->iface_list, new);
if (!k) return; /* We are not interested in this interface */
DBG("adding interface %s\n", new->name );
rif = new_iface(p, new, new->flags);
rif->patt = (void *) k;
add_head( &P->interfaces, NODE rif );
}
}
static void
rip_rt_notify(struct proto *p, struct network *net, struct rte *new, struct rte *old)
{
CHK_MAGIC;
if (old) {
struct rip_entry *e = fib_find( &P->rtable, &net->n.prefix, net->n.pxlen );
if (!e)
log( L_BUG "Deleting nonexistent entry?!" );
fib_delete( &P->rtable, e );
}
if (new) {
struct rip_entry *e;
if (fib_find( &P->rtable, &net->n.prefix, net->n.pxlen ))
log( L_BUG "Inserting entry which is already there?" );
e = fib_get( &P->rtable, &net->n.prefix, net->n.pxlen );
e->nexthop = new->attrs->gw;
e->tag = new->u.rip.tag;
e->metric = new->u.rip.metric;
e->whotoldme = new->attrs->from;
e->updated = e->changed = now;
e->flags = 0;
}
}
static int
rip_rte_better(struct rte *new, struct rte *old)
{
if (old->u.rip.metric < new->u.rip.metric)
return 0;
if (old->u.rip.metric > new->u.rip.metric)
return 1;
#define old_metric_is_much_older_than_new_metric 0
if ((old->u.rip.metric == new->u.rip.metric) && (old_metric_is_much_older_than_new_metric))
return 1;
return 0;
}
static void
rip_rte_insert(net *net, rte *rte)
{
struct proto *p = rte->attrs->proto;
add_head( &P->garbage, &rte->u.rip.garbage );
}
static void
rip_rte_remove(net *net, rte *rte)
{
struct proto *p = rte->attrs->proto;
rem_node( &rte->u.rip.garbage );
}
void
rip_init_instance(struct proto *p)
{
p->preference = DEF_PREF_RIP;
p->if_notify = rip_if_notify;
p->rt_notify = rip_rt_notify;
p->rte_better = rip_rte_better;
p->rte_insert = rip_rte_insert;
p->rte_remove = rip_rte_remove;
}
void
rip_init_config(struct rip_proto_config *c)
{
init_list(&c->iface_list);
c->infinity = 16;
c->port = 520;
c->period = 30;
c->garbage_time = 120+180;
}
static void
rip_preconfig(struct protocol *x, struct config *c)
{
DBG( "RIP: preconfig\n" );
}
static void
rip_postconfig(struct proto_config *c)
{
}
struct protocol proto_rip = {
name: "RIP",
preconfig: rip_preconfig,
postconfig: rip_postconfig,
init: rip_init,
dump: rip_dump,
start: rip_start,
};