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bird/proto/rip/rip.c
Ondrej Zajicek 70e212f913 Implements TTL security for OSPF and RIP.
Interfaces for OSPF and RIP could be configured to use (and request)
TTL 255 for traffic to direct neighbors.

Thanks to Simon Dickhoven for the original patch for RIPng.
2013-06-25 15:39:44 +02:00

1065 lines
28 KiB
C

/*
* Rest in pieces - RIP protocol
*
* Copyright (c) 1998, 1999 Pavel Machek <pavel@ucw.cz>
* 2004 Ondrej Filip <feela@network.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*
FIXME: IPv6 support: packet size
FIXME: (nonurgent) IPv6 support: receive "route using" blocks
FIXME: (nonurgent) IPv6 support: generate "nexthop" blocks
next hops are only advisory, and they are pretty ugly in IPv6.
I suggest just forgetting about them.
FIXME: (nonurgent): fold rip_connection into rip_interface?
FIXME: propagation of metric=infinity into main routing table may or may not be good idea.
*/
/**
* DOC: Routing Information Protocol
*
* RIP is a pretty simple protocol, so about a half of its code is interface
* with the core.
*
* We maintain our own linked list of &rip_entry structures -- it serves
* as our small routing table. RIP never adds to this linked list upon
* packet reception; instead, it lets the core know about data from the packet
* and waits for the core to call rip_rt_notify().
*
* Within rip_tx(), the list is
* walked and a packet is generated using rip_tx_prepare(). This gets
* tricky because we may need to send more than one packet to one
* destination. Struct &rip_connection is used to hold context information such as how
* many of &rip_entry's we have already sent and it's also used to protect
* against two concurrent sends to one destination. Each &rip_interface has
* at most one &rip_connection.
*
* We are not going to honor requests for sending part of
* routing table. That would need to turn split horizon off etc.
*
* About triggered updates, RFC says: when a triggered update was sent,
* don't send a new one for something between 1 and 5 seconds (and send one
* after that). We do something else: each 5 seconds,
* we look for any changed routes and broadcast them.
*/
#undef LOCAL_DEBUG
#define LOCAL_DEBUG 1
#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 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);
/*
* Output processing
*
* This part is responsible for getting packets out to the network.
*/
static void
rip_tx_err( sock *s, int err )
{
struct rip_connection *c = ((struct rip_interface *)(s->data))->busy;
struct proto *p = c->proto;
log( L_ERR "%s: Unexpected error at rip transmit: %M", p->name, err );
}
/*
* rip_tx_prepare:
* @e: rip entry that needs to be translated to form suitable for network
* @b: block to be filled
*
* Fill one rip block with info that needs to go to the network. Handle
* nexthop and split horizont correctly. (Next hop is ignored for IPv6,
* that could be fixed but it is not real problem).
*/
static int
rip_tx_prepare(struct proto *p, struct rip_block *b, struct rip_entry *e, struct rip_interface *rif, int pos )
{
int metric;
DBG( "." );
b->tag = htons( e->tag );
b->network = e->n.prefix;
metric = e->metric;
if (neigh_connected_to(p, &e->whotoldme, rif->iface)) {
DBG( "(split horizon)" );
metric = P_CF->infinity;
}
#ifndef IPV6
b->family = htons( 2 ); /* AF_INET */
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 );
b->metric = htonl( metric );
#else
b->pxlen = e->n.pxlen;
b->metric = metric; /* it is u8 */
#endif
ipa_hton( b->network );
return pos+1;
}
/*
* rip_tx - send one rip packet to the 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;
int maxi, nullupdate = 1;
DBG( "Sending to %I\n", s->daddr );
do {
if (c->done)
goto done;
DBG( "Preparing packet to send: " );
packet->heading.command = RIPCMD_RESPONSE;
#ifndef IPV6
packet->heading.version = RIP_V2;
#else
packet->heading.version = RIP_NG;
#endif
packet->heading.unused = 0;
i = !!P_CF->authtype;
#ifndef IPV6
maxi = ((P_CF->authtype == AT_MD5) ? PACKET_MD5_MAX : PACKET_MAX);
#else
maxi = 5; /* We need to have at least reserve of one at end of packet */
#endif
FIB_ITERATE_START(&P->rtable, &c->iter, z) {
struct rip_entry *e = (struct rip_entry *) z;
if (!rif->triggered || (!(e->updated < now-2))) { /* FIXME: Should be probably 1 or some different algorithm */
nullupdate = 0;
i = rip_tx_prepare( p, packet->block + i, e, rif, i );
if (i >= maxi) {
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 (nullupdate) {
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;
}
/*
* rip_sendto - send whole routing table to selected destination
* @rif: interface to use. Notice that we lock interface so that at
* most one send to one interface is done.
*/
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 "%s: Interface %s is much too slow, dropping request", p->name, 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");
c->done = 0;
FIB_ITERATE_INIT( &c->iter, &P->rtable );
add_head( &P->connections, NODE c );
if (ipa_nonzero(daddr))
TRACE(D_PACKETS, "Sending my routing table to %I:%d on %s", daddr, dport, rif->iface->name );
else
TRACE(D_PACKETS, "Broadcasting routing table to %s", 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
*
* This part is responsible for any updates that come from network
*/
static void
rip_rte_update_if_better(rtable *tab, net *net, struct proto *p, rte *new)
{
rte *old;
old = rte_find(net, p);
if (!old || p->rte_better(new, old) ||
(ipa_equal(old->attrs->from, new->attrs->from) &&
(old->u.rip.metric != new->u.rip.metric)) )
rte_update(tab, net, p, p, new);
else
rte_free(new);
}
/*
* advertise_entry - let main routing table know about our new entry
* @b: entry in network format
*
* This basically translates @b to format used by bird core and feeds
* bird core with this route.
*/
static void
advertise_entry( struct proto *p, struct rip_block *b, ip_addr whotoldme, struct iface *iface )
{
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
/* FIXME: next hop is in other packet for v6 */
A.gw = whotoldme;
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_find2( p, &A.gw, iface, 0 );
if (!neighbor) {
log( L_REMOTE "%s: %I asked me to route %I/%d using not-neighbor %I.", p->name, A.from, b->network, pxlen, A.gw );
return;
}
if (neighbor->scope == SCOPE_HOST) {
DBG("Self-destined route, ignoring.\n");
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.");
/* set to: interface of nexthop */
a = rta_lookup(&A);
if (pxlen==-1) {
log( L_REMOTE "%s: %I gave me invalid pxlen/netmask for %I.", p->name, A.from, b->network );
return;
}
n = net_get( p->table, b->network, pxlen );
r = rte_get_temp(a);
#ifndef IPV6
r->u.rip.metric = ntohl(b->metric) + rif->metric;
#else
r->u.rip.metric = b->metric + rif->metric;
#endif
r->u.rip.entry = NULL;
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 */
rip_rte_update_if_better( p->table, n, p, r );
DBG( "done\n" );
}
/*
* process_block - do some basic check and pass block to advertise_entry
*/
static void
process_block( struct proto *p, struct rip_block *block, ip_addr whotoldme, struct iface *iface )
{
int metric, pxlen;
#ifndef IPV6
metric = ntohl( block->metric );
pxlen = ipa_mklen(block->netmask);
#else
metric = block->metric;
pxlen = block->pxlen;
#endif
ip_addr network = block->network;
CHK_MAGIC;
TRACE(D_ROUTES, "block: %I tells me: %I/%d available, metric %d... ",
whotoldme, network, pxlen, metric );
if ((!metric) || (metric > P_CF->infinity)) {
#ifdef IPV6 /* Someone is sending us nexthop and we are ignoring it */
if (metric == 0xff)
{ DBG( "IPv6 nexthop ignored" ); return; }
#endif
log( L_WARN "%s: Got metric %d from %I", p->name, metric, whotoldme );
return;
}
advertise_entry( p, block, whotoldme, iface );
}
#define BAD( x ) { log( L_REMOTE "%s: " x, p->name ); return 1; }
/*
* rip_process_packet - this is main routine for incoming packets.
*/
static int
rip_process_packet( struct proto *p, struct rip_packet *packet, int num, ip_addr whotoldme, int port, struct iface *iface )
{
int i;
int authenticated = 0;
neighbor *neighbor;
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->honor == HO_NEVER)
BAD( "They asked me to send routing table, but I was told not to do it" );
if ((P_CF->honor == HO_NEIGHBOR) && (!neigh_find2( p, &whotoldme, iface, 0 )))
BAD( "They asked me to send routing table, but he is not my neighbor" );
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 "%s: %I send me routing info from port %d", p->name, whotoldme, port );
return 1;
}
if (!(neighbor = neigh_find2( p, &whotoldme, iface, 0 )) || neighbor->scope == SCOPE_HOST) {
log( L_REMOTE "%s: %I send me routing info but he is not my neighbor", p->name, whotoldme );
return 0;
}
for (i=0; i<num; i++) {
struct rip_block *block = &packet->block[i];
#ifndef IPV6
/* Authentication is not defined for v6 */
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;
}
#endif
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, iface );
}
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;
}
/*
* rip_rx - Receive hook: do basic checks and pass packet to rip_process_packet
*/
static int
rip_rx(sock *s, int size)
{
struct rip_interface *i = s->data;
struct proto *p = i->proto;
struct iface *iface = NULL;
int num;
/* In non-listening mode, just ignore packet */
if (i->mode & IM_NOLISTEN)
return 1;
#ifdef IPV6
if (! i->iface || s->lifindex != i->iface->index)
return 1;
iface = i->iface;
#endif
if (i->check_ttl && (s->ttl < 255))
{
log( L_REMOTE "%s: Discarding packet with TTL %d (< 255) from %I on %s",
p->name, s->ttl, s->faddr, i->iface->name);
return 1;
}
CHK_MAGIC;
DBG( "RIP: message came: %d bytes from %I via %s\n", size, s->faddr, i->iface ? i->iface->name : "(dummy)" );
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>PACKET_MAX) BAD( "Too many blocks" );
if (ipa_equal(i->iface->addr->ip, s->faddr)) {
DBG("My own packet\n");
return 1;
}
rip_process_packet( p, (struct rip_packet *) s->rbuf, num, s->faddr, s->fport, iface );
return 1;
}
/*
* Interface to BIRD core
*/
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 );
debug( "\n" );
}
/**
* rip_timer
* @t: timer
*
* Broadcast routing tables periodically (using rip_tx) and kill
* routes that are too old. RIP keeps a list of its own entries present
* in the core table by a linked list (functions rip_rte_insert() and
* rip_rte_delete() are responsible for that), it walks this list in the timer
* and in case an entry is too old, it is discarded.
*/
static void
rip_timer(timer *t)
{
struct proto *p = t->data;
struct fib_node *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 );
CHK_MAGIC;
DBG( "Garbage: (%p)", rte ); rte_dump( rte );
if (now - rte->lastmod > P_CF->timeout_time) {
TRACE(D_EVENTS, "entry is too old: %I", rte->net->n.prefix );
if (rte->u.rip.entry) {
rte->u.rip.entry->metric = P_CF->infinity;
rte->u.rip.metric = P_CF->infinity;
}
}
if (now - rte->lastmod > P_CF->garbage_time) {
TRACE(D_EVENTS, "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;
if ( P_CF->period > 2 ) { /* Bring some randomness into sending times */
if (! (P->tx_count % P_CF->period)) P->rnd_count = random_u32() % 2;
} else P->rnd_count = P->tx_count % P_CF->period;
WALK_LIST( rif, P->interfaces ) {
struct iface *iface = rif->iface;
if (!iface) continue;
if (rif->mode & IM_QUIET) continue;
if (!(iface->flags & IF_UP)) continue;
rif->triggered = P->rnd_count;
rip_sendto( p, IPA_NONE, 0, rif );
}
P->tx_count++;
P->rnd_count--;
}
DBG( "RIP: tick tock done\n" );
}
/*
* rip_start - initialize instance of rip
*/
static int
rip_start(struct proto *p)
{
struct rip_interface *rif;
DBG( "RIP: starting instance...\n" );
ASSERT(sizeof(struct rip_packet_heading) == 4);
ASSERT(sizeof(struct rip_block) == 20);
ASSERT(sizeof(struct rip_block_auth) == 20);
#ifdef LOCAL_DEBUG
P->magic = RIP_MAGIC;
#endif
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->recurrent = 1;
P->timer->hook = rip_timer;
tm_start( P->timer, 2 );
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;
struct rip_interface *rif;
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( (struct rip_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, ea_list *attrs)
{
eattr *metric = ea_find(attrs, EA_RIP_METRIC);
eattr *tag = ea_find(attrs, EA_RIP_TAG);
buf += bsprintf(buf, " (%d/%d)", rte->pref, metric ? metric->u.data : 0);
if (tag && tag->u.data)
bsprintf(buf, " t%04x", tag->u.data);
}
static void
kill_iface(struct rip_interface *i)
{
DBG( "RIP: Interface %s disappeared\n", i->iface->name);
rfree(i->sock);
mb_free(i);
}
/**
* new_iface
* @p: myself
* @new: interface to be created or %NULL if we are creating a magic
* socket. The magic socket is used for listening and also for
* sending requested responses.
* @flags: interface flags
* @patt: pattern this interface matched, used for access to config options
*
* Create an interface structure and start listening on the interface.
*/
static struct rip_interface *
new_iface(struct proto *p, struct iface *new, unsigned long flags, struct iface_patt *patt )
{
struct rip_interface *rif;
struct rip_patt *PATT = (struct rip_patt *) patt;
rif = mb_allocz(p->pool, sizeof( struct rip_interface ));
rif->iface = new;
rif->proto = p;
rif->busy = NULL;
if (PATT) {
rif->mode = PATT->mode;
rif->metric = PATT->metric;
rif->multicast = (!(PATT->mode & IM_BROADCAST)) && (flags & IF_MULTICAST);
rif->check_ttl = (PATT->ttl_security == 1);
}
/* 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 = 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->tos = PATT->tx_tos;
rif->sock->priority = PATT->tx_priority;
rif->sock->ttl = PATT->ttl_security ? 255 : 1;
rif->sock->flags = SKF_LADDR_RX | (rif->check_ttl ? SKF_TTL_RX : 0);
}
if (new) {
if (new->addr->flags & IA_PEER)
log( L_WARN "%s: rip is not defined over unnumbered links", p->name );
rif->sock->saddr = IPA_NONE;
if (rif->multicast) {
#ifndef IPV6
rif->sock->daddr = ipa_from_u32(0xe0000009);
#else
rif->sock->daddr = ipa_build(0xff020000, 0, 0, 9);
#endif
} else {
rif->sock->daddr = new->addr->brd;
}
}
if (!ipa_nonzero(rif->sock->daddr)) {
if (rif->iface)
log( L_WARN "%s: interface %s is too strange for me", p->name, rif->iface->name );
} else {
if (sk_open(rif->sock)<0)
goto err;
if (rif->multicast)
{
if (sk_setup_multicast(rif->sock) < 0)
goto err;
if (sk_join_group(rif->sock, rif->sock->daddr) < 0)
goto err;
}
else
{
if (sk_set_broadcast(rif->sock, 1) < 0)
goto err;
}
}
TRACE(D_EVENTS, "Listening on %s, port %d, mode %s (%I)", rif->iface ? rif->iface->name : "(dummy)", P_CF->port, rif->multicast ? "multicast" : "broadcast", rif->sock->daddr );
return rif;
err:
log( L_ERR "%s: could not create socket for %s", p->name, rif->iface ? rif->iface->name : "(dummy)" );
if (rif->iface) {
rfree(rif->sock);
mb_free(rif);
return NULL;
}
/* On dummy, we just return non-working socket, so that user gets error every time anyone requests table */
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_find(&P_CF->iface_list, iface, iface->addr);
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);
if (rif) {
add_head( &P->interfaces, NODE rif );
DBG("Adding object lock of %p for %p\n", lock, rif);
rif->lock = lock;
} else { rfree(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);
rfree(i->lock);
kill_iface(i);
}
}
if (c & IF_CHANGE_UP) {
struct iface_patt *k = iface_patt_find(&P_CF->iface_list, iface, iface->addr);
struct object_lock *lock;
struct rip_patt *PATT = (struct rip_patt *) k;
if (!k) return; /* We are not interested in this interface */
lock = olock_new( p->pool );
if (!(PATT->mode & IM_BROADCAST) && (iface->flags & IF_MULTICAST))
#ifndef IPV6
lock->addr = ipa_from_u32(0xe0000009);
#else
ip_pton("FF02::9", &lock->addr);
#endif
else
lock->addr = iface->addr->brd;
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 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(pool, 1, 0);
new->next = *attrs;
*attrs = new;
}
return 0;
}
static struct ea_list *
rip_make_tmp_attrs(struct rte *rt, struct linpool *pool)
{
return rip_gen_attrs(pool, rt->u.rip.metric, rt->u.rip.tag);
}
static void
rip_store_tmp_attrs(struct rte *rt, struct ea_list *attrs)
{
rt->u.rip.tag = ea_get_int(attrs, EA_RIP_TAG, 0);
rt->u.rip.metric = ea_get_int(attrs, EA_RIP_METRIC, 1);
}
/*
* rip_rt_notify - core tells us about new route (possibly our
* own), so store it into our data structures.
*/
static void
rip_rt_notify(struct proto *p, struct rtable *table UNUSED, struct network *net,
struct rte *new, struct rte *old UNUSED, struct ea_list *attrs)
{
CHK_MAGIC;
struct rip_entry *e;
e = fib_find( &P->rtable, &net->n.prefix, net->n.pxlen );
if (e)
fib_delete( &P->rtable, e );
if (new) {
e = fib_get( &P->rtable, &net->n.prefix, net->n.pxlen );
e->nexthop = new->attrs->gw;
e->metric = 0;
e->whotoldme = IPA_NONE;
new->u.rip.entry = e;
e->tag = ea_get_int(attrs, EA_RIP_TAG, 0);
e->metric = ea_get_int(attrs, EA_RIP_METRIC, 1);
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_same(struct rte *new, struct rte *old)
{
/* new->attrs == old->attrs always */
return new->u.rip.metric == old->u.rip.metric;
}
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->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->lastmod) > (P_CF->timeout_time / 2)))
return 1;
return 0;
}
/*
* rip_rte_insert - we maintain linked list of "our" entries in main
* routing table, so that we can timeout them correctly. rip_timer()
* walks the list.
*/
static void
rip_rte_insert(net *net UNUSED, rte *rte)
{
struct proto *p = rte->attrs->proto;
CHK_MAGIC;
DBG( "rip_rte_insert: %p\n", rte );
add_head( &P->garbage, &rte->u.rip.garbage );
}
/*
* rip_rte_remove - link list maintenance
*/
static void
rip_rte_remove(net *net UNUSED, rte *rte)
{
#ifdef LOCAL_DEBUG
struct proto *p = rte->attrs->proto;
CHK_MAGIC;
DBG( "rip_rte_remove: %p\n", rte );
#endif
rem_node( &rte->u.rip.garbage );
}
void
rip_init_instance(struct proto *p)
{
p->accept_ra_types = RA_OPTIMAL;
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_same = rip_rte_same;
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 = RIP_PORT;
c->period = 30;
c->garbage_time = 120+180;
c->timeout_time = 120;
c->passwords = NULL;
c->authtype = AT_NONE;
}
static int
rip_get_attr(eattr *a, byte *buf, int buflen UNUSED)
{
switch (a->id) {
case EA_RIP_METRIC: bsprintf( buf, "metric: %d", a->u.data ); return GA_FULL;
case EA_RIP_TAG: bsprintf( buf, "tag: %d", a->u.data ); return GA_FULL;
default: return GA_UNKNOWN;
}
}
static int
rip_pat_compare(struct rip_patt *a, struct rip_patt *b)
{
return ((a->metric == b->metric) &&
(a->mode == b->mode) &&
(a->tx_tos == b->tx_tos) &&
(a->tx_priority == b->tx_priority));
}
static int
rip_reconfigure(struct proto *p, struct proto_config *c)
{
struct rip_proto_config *new = (struct rip_proto_config *) c;
int generic = sizeof(struct proto_config) + sizeof(list) /* + sizeof(struct password_item *) */;
if (!iface_patts_equal(&P_CF->iface_list, &new->iface_list, (void *) rip_pat_compare))
return 0;
return !memcmp(((byte *) P_CF) + generic,
((byte *) new) + generic,
sizeof(struct rip_proto_config) - generic);
}
static void
rip_copy_config(struct proto_config *dest, struct proto_config *src)
{
/* Shallow copy of everything */
proto_copy_rest(dest, src, sizeof(struct rip_proto_config));
/* We clean up iface_list, ifaces are non-sharable */
init_list(&((struct rip_proto_config *) dest)->iface_list);
/* Copy of passwords is OK, it just will be replaced in dest when used */
}
struct protocol proto_rip = {
name: "RIP",
template: "rip%d",
attr_class: EAP_RIP,
preference: DEF_PREF_RIP,
get_route_info: rip_get_route_info,
get_attr: rip_get_attr,
init: rip_init,
dump: rip_dump,
start: rip_start,
reconfigure: rip_reconfigure,
copy_config: rip_copy_config
};