/* * Rest in pieces - RIP protocol * * Copyright (c) 1998, 1999 Pavel Machek * * Can be freely distributed and used under the terms of the GNU GPL. * FIXME: IpV6 support: packet size FIXME: IpV6 support: use right address for broadcasts FIXME: IpV6 support: receive "route using" blocks FIXME (nonurgent): fold rip_connection into rip_interface? We are not going to honour requests for sending part of routing table. That would need to turn split horizon off, etc. Triggered updates. When triggered update was sent, don't send new one for something between 1 and 5 seconds (and send one after that), says RFC. We do something else: once in 5 second we look for any changed routes and broadcast them. FIXME: (nonurgent) allow bigger frequencies than 1 regular update in 6 seconds (?) FIXME: propagation of metric=infinity into main routing table may or may not be good idea. FIXME: mj wants us to be able to format attributes: Each protocol can now register its own attribute class (protocol->attr_class, set to EAP_xxx) and also a callback for naming and formatting of attributes. The callback can return one of the following results: GA_UNKNOWN Attribute not recognized. GA_NAME Attribute name recognized and put to the buffer, generic code should format the value. GA_FULL Both attribute name and value put to the buffer. Please update protocols generating dynamic attributes to provide the attr_class and formatting hook. */ #define LOCAL_DEBUG #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 "lib/string.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) #define TRACE(level, msg, args...) do { if (p->debug & level) { log(L_TRACE "%s: " msg, p->name , ## args); } } while(0) static struct rip_interface *new_iface(struct proto *p, struct iface *new, unsigned long flags, struct iface_patt *patt); #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_prepare(struct proto *p, ip_addr daddr, struct rip_block *b, struct rip_entry *e, struct rip_interface *rif ) { DBG( "." ); b->family = htons( 2 ); /* AF_INET */ b->tag = htons( e->tag ); b->network = e->n.prefix; #ifndef IPV6 b->netmask = ipa_mkmask( e->n.pxlen ); ipa_hton( b->netmask ); if (neigh_connected_to(p, &e->nexthop, rif->iface)) b->nexthop = e->nexthop; else b->nexthop = IPA_NONE; ipa_hton( b->nexthop ); #else b->pxlen = e->n.pxlen; #endif b->metric = htonl( e->metric ); if (neigh_connected_to(p, &e->whotoldme, rif->iface)) { DBG( "(split horizon)" ); b->metric = htonl( P_CF->infinity ); } ipa_hton( b->network ); } 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, packetlen; DBG( "Sending to %I\n", s->daddr ); do { if (c->done) goto done; DBG( "Preparing packet to send: " ); packet->heading.command = RIPCMD_RESPONSE; packet->heading.version = RIP_V2; packet->heading.unused = 0; i = !!P_CF->authtype; FIB_ITERATE_START(&P->rtable, &c->iter, z) { struct rip_entry *e = (struct rip_entry *) z; if (!rif->triggered || (!(e->updated < now-5))) { rip_tx_prepare( p, s->daddr, packet->block + i, e, rif ); if (i++ == ((P_CF->authtype == AT_MD5) ? PACKET_MD5_MAX : PACKET_MAX)) { FIB_ITERATE_PUT(&c->iter, z); goto break_loop; } } } FIB_ITERATE_END(z); c->done = 1; break_loop: packetlen = rip_outgoing_authentication(p, (void *) &packet->block[0], packet, i); DBG( ", sending %d blocks, ", i ); if (i == !!P_CF->authtype) { DBG( "not sending NULL update\n" ); c->done = 1; goto done; } if (ipa_nonzero(c->daddr)) i = sk_send_to( s, packetlen, c->daddr, c->dport ); else i = sk_send( s, packetlen ); DBG( "it wants more\n" ); } while (i>0); if (i<0) rip_tx_err( s, i ); DBG( "blocked\n" ); return; done: DBG( "Looks like I'm" ); c->rif->busy = NULL; rem_node(NODE c); mb_free(c); DBG( " done\n" ); return; } 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; static int num = 0; if (rif->busy) { log (L_WARN "Interface %s is much too slow, dropping request", iface->name); return; } c = mb_alloc( p->pool, sizeof( struct rip_connection )); 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 ); TRACE(D_PACKETS, "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 */ /* 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; int pxlen; bzero(&A, sizeof(A)); A.proto = p; A.source = RTS_RIP; A.scope = SCOPE_UNIVERSE; A.cast = RTC_UNICAST; A.dest = RTD_ROUTER; A.flags = 0; #ifndef IPV6 A.gw = ipa_nonzero(b->nexthop) ? b->nexthop : whotoldme; pxlen = ipa_mklen(b->netmask); #else A.gw = whotoldme; /* FIXME: next hop is in other packet for v6 */ pxlen = b->pxlen; #endif A.from = whotoldme; /* No need to look if destination looks valid - ie not net 0 or 127 -- core will do for us. */ neighbor = neigh_find( p, &A.gw, 0 ); if (!neighbor) { log( L_REMOTE "%I asked me to route %I/%d using not-neighbor %I.", A.from, b->network, pxlen, 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 (pxlen==-1) { log( L_REMOTE "%I gave me invalid pxlen/netmask for %I.", A.from, b->network ); return; } n = net_get( p->table, b->network, pxlen ); r = rte_get_temp(a); r->u.rip.metric = ntohl(b->metric) + rif->patt->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( p->table, n, p, r ); DBG( "done\n" ); } static void process_block( struct proto *p, struct rip_block *block, ip_addr whotoldme ) { int metric = ntohl( block->metric ); ip_addr network = block->network; CHK_MAGIC; TRACE(D_ROUTES, "block: %I tells me: %I/??? available, metric %d... ", whotoldme, network, metric ); if ((!metric) || (metric > P_CF->infinity)) { log( L_WARN "Got metric %d from %I", metric, whotoldme ); return; } advertise_entry( p, block, whotoldme ); } #define BAD( x ) { log( L_REMOTE "%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, authenticated = 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" ); if (P_CF->honour == HO_NEVER) { log( L_REMOTE "They asked me to send routing table, but I was told not to do it" ); return 0; } if ((P_CF->honour == HO_NEIGHBOUR) && (!neigh_find( p, &whotoldme, 0 ))) { log( L_REMOTE "They asked me to send routing table, but he is not my neighbour" ); return 0; } rip_sendto( p, whotoldme, port, HEAD(P->interfaces) ); /* no broadcast */ break; case RIPCMD_RESPONSE: DBG( "*** Rtable from %I\n", whotoldme ); if (port != P_CF->port) { log( L_REMOTE "%I send me routing info from port %d", whotoldme, port ); #if 0 return 0; #else log( L_REMOTE "...ignoring" ); #endif } if (!neigh_find( p, &whotoldme, 0 )) { log( L_REMOTE "%I send me routing info but he is not my neighbour", whotoldme ); #if 0 return 0; #else log( L_REMOTE "...ignoring" ); #endif } for (i=0; iblock[i]; if (block->family == 0xffff) { if (i) continue; /* md5 tail has this family */ if (rip_incoming_authentication(p, (void *) block, packet, num, whotoldme)) BAD( "Authentication failed" ); authenticated = 1; continue; } if ((!authenticated) && (P_CF->authtype != AT_NONE)) BAD( "Packet is not authenticated and it should be" ); ipa_ntoh( block->network ); #ifndef IPV6 ipa_ntoh( block->netmask ); ipa_ntoh( block->nexthop ); if (packet->heading.version == RIP_V1) /* FIXME (nonurgent): switch to disable this? */ block->netmask = ipa_class_mask(block->network); #endif 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" ); } 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->u.rip.lastmodX > P_CF->timeout_time) { TRACE(D_EVENTS, "RIP: entry is too old: %I", rte->net->n.prefix ); e->metric = P_CF->infinity; } if (now - rte->u.rip.lastmodX > P_CF->garbage_time) { TRACE(D_EVENTS, "RIP: entry is much too old: %I", rte->net->n.prefix ); rte_discard(p->table, rte); } } DBG( "RIP: Broadcasting routing tables\n" ); { struct rip_interface *rif; P->tx_count ++; 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; rif->triggered = (P->tx_count % 6); 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 / 6)+1; P->timer->hook = rip_timer; tm_start( P->timer, 5 ); rif = new_iface(p, NULL, 0, NULL); /* 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 void rip_get_route_info(rte *rte, byte *buf) { buf += bsprintf(buf, " (%d/%d)", rte->pref, rte->u.rip.metric ); bsprintf(buf, " t%04x", rte->u.rip.tag ); } 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 */ static struct rip_interface * new_iface(struct proto *p, struct iface *new, unsigned long flags, struct iface_patt *patt ) { struct rip_interface *rif; rif = mb_allocz(p->pool, sizeof( struct rip_interface )); rif->iface = new; rif->proto = p; rif->busy = NULL; rif->patt = (struct rip_patt *) patt; if (rif->patt) rif->multicast = (!(rif->patt->mode & IM_BROADCAST)) && (flags & IF_MULTICAST); /* lookup multicasts over unnumbered links - no: rip is not defined over unnumbered links */ if (rif->multicast) DBG( "Doing multicasts!\n" ); rif->sock = sk_new( p->pool ); rif->sock->type = rif->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; if (new) rif->sock->ttl = 1; else rif->sock->ttl = 30; rif->sock->tos = IP_PREC_INTERNET_CONTROL; if (new) { if (new->addr->flags & IA_UNNUMBERED) log( L_WARN "%s: rip is not defined over unnumbered links", P_NAME ); if (rif->multicast) { rif->sock->daddr = ipa_from_u32(0xe0000009); rif->sock->saddr = ipa_from_u32(0xe0000009); } else rif->sock->daddr = new->addr->brd; } if (!ipa_nonzero(rif->sock->daddr)) { log( L_WARN "%s: interface %s is too strange for me", P_NAME, rif->iface ? rif->iface->name : "(dummy)" ); } else if (!(rif->patt->mode & IM_NOLISTEN)) if (sk_open(rif->sock)<0) { log( L_ERR "%s: could not listen on %s", P_NAME, rif->iface ? rif->iface->name : "(dummy)" ); /* Don't try to transmit into this one? Well, why not? This should not happen, anyway :-) */ } TRACE(D_EVENTS, "%s: listening on %s, port %d, mode %s (%I)", P_NAME, rif->iface ? rif->iface->name : "(dummy)", P_CF->port, rif->multicast ? "multicast" : "broadcast", rif->sock->daddr ); return rif; } static void rip_real_if_add(struct object_lock *lock) { struct iface *iface = lock->iface; struct proto *p = lock->data; struct rip_interface *rif; struct iface_patt *k = iface_patt_match(&P_CF->iface_list, iface); if (!k) bug("This can not happen! It existed few seconds ago!" ); DBG("adding interface %s\n", iface->name ); rif = new_iface(p, iface, iface->flags, k); add_head( &P->interfaces, NODE rif ); rif->lock = lock; } static void rip_if_notify(struct proto *p, unsigned c, struct iface *iface) { DBG( "RIP: if notify\n" ); if (iface->flags & IF_IGNORE) return; if (c & IF_CHANGE_DOWN) { struct rip_interface *i; i = find_interface(p, iface); if (i) { rem_node(NODE i); kill_iface(p, i); rfree(i->lock); } } if (c & IF_CHANGE_UP) { struct rip_interface *rif; struct iface_patt *k = iface_patt_match(&P_CF->iface_list, iface); struct object_lock *lock; if (!k) return; /* We are not interested in this interface */ lock = olock_new( p->pool ); lock->addr = ipa_from_u32(0xe0000009); lock->port = P_CF->port; lock->iface = iface; lock->hook = rip_real_if_add; lock->data = p; lock->type = OBJLOCK_UDP; olock_acquire(lock); } } static struct ea_list * rip_gen_attrs(struct proto *p, struct linpool *pool, int metric, u16 tag) { struct ea_list *l = lp_alloc(pool, sizeof(struct ea_list) + 2*sizeof(eattr)); l->next = NULL; l->flags = EALF_SORTED; l->count = 2; l->attrs[0].id = EA_RIP_TAG; l->attrs[0].flags = 0; l->attrs[0].type = EAF_TYPE_INT | EAF_TEMP; l->attrs[0].u.data = tag; l->attrs[1].id = EA_RIP_METRIC; l->attrs[1].flags = 0; l->attrs[1].type = EAF_TYPE_INT | EAF_TEMP; l->attrs[1].u.data = metric; return l; } static int rip_import_control(struct proto *p, struct rte **rt, struct ea_list **attrs, struct linpool *pool) { if ((*rt)->attrs->proto == p) /* My own must not be touched */ return 1; if ((*rt)->attrs->source != RTS_RIP) { struct ea_list *new = rip_gen_attrs(p, pool, 1, 0); new->next = *attrs; *attrs = new; } return 0; } static struct ea_list * rip_make_tmp_attrs(struct rte *rt, struct linpool *pool) { struct proto *p = rt->attrs->proto; return rip_gen_attrs(p, pool, rt->u.rip.metric, rt->u.rip.tag); } static void rip_store_tmp_attrs(struct rte *rt, struct ea_list *attrs) { struct proto *p = rt->attrs->proto; rt->u.rip.tag = ea_find(attrs, EA_RIP_TAG)->u.data; rt->u.rip.metric = ea_find(attrs, EA_RIP_METRIC)->u.data; } static void rip_rt_notify(struct proto *p, struct network *net, struct rte *new, struct rte *old, struct ea_list *attrs) { 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->metric = 0; e->whotoldme = IPA_NONE; e->tag = ea_find(attrs, EA_RIP_TAG)->u.data; e->metric = ea_find(attrs, EA_RIP_METRIC)->u.data; if (e->metric > P_CF->infinity) e->metric = P_CF->infinity; if (new->attrs->proto == p) e->whotoldme = new->attrs->from; if (!e->metric) /* That's okay: this way user can set his own value for external routes in rip. */ e->metric = 5; e->updated = e->changed = now; e->flags = 0; } } static int rip_rte_better(struct rte *new, struct rte *old) { struct proto *p = new->attrs->proto; if (ipa_equal(old->attrs->from, new->attrs->from)) return 1; if (old->u.rip.metric < new->u.rip.metric) return 0; if (old->u.rip.metric > new->u.rip.metric) return 1; if ((old->u.rip.metric < 16) && (new->u.rip.metric == P_CF->infinity)) { new->u.rip.lastmodX = now - P_CF->timeout_time; /* Check this: if new metric is 16, act as it was timed out */ } if (old->attrs->proto == new->attrs->proto) /* This does not make much sense for different protocols */ if ((old->u.rip.metric == new->u.rip.metric) && ((now - old->u.rip.lastmodX) > (P_CF->timeout_time / 2))) return 1; return 0; } static void rip_rte_insert(net *net, rte *rte) { struct proto *p = rte->attrs->proto; rte->u.rip.lastmodX = now; 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->import_control = rip_import_control; p->make_tmp_attrs = rip_make_tmp_attrs; p->store_tmp_attrs = rip_store_tmp_attrs; 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; c->timeout_time = 120; c->passwords = NULL; c->authtype = AT_NONE; } static void rip_preconfig(struct protocol *x, struct config *c) { DBG( "RIP: preconfig\n" ); } struct protocol proto_rip = { name: "RIP", template: "rip%d", attr_class: EAP_RIP, preconfig: rip_preconfig, get_route_info: rip_get_route_info, init: rip_init, dump: rip_dump, start: rip_start, };