/* Supply dst with the contents of the routing tables.
* If this won't fit in one packet, chop it up into several.
*/
void
supply(struct sockaddr_in *dst,
struct interface *ifp, /* output interface */
enum output_type type,
int flash, /* 1=flash update */
int vers, /* RIP version */
int passwd_ok) /* OK to include cleartext password */
{
struct rt_entry *rt;
int def_metric;
ws.state = 0;
ws.gen_limit = 1024;
ws.to = *dst;
ws.to_std_mask = std_mask(ws.to.sin_addr.s_addr);
ws.to_std_net = ntohl(ws.to.sin_addr.s_addr) & ws.to_std_mask;
if (ifp != NULL) {
ws.to_mask = ifp->int_mask;
ws.to_net = ifp->int_net;
if (on_net(ws.to.sin_addr.s_addr, ws.to_net, ws.to_mask))
ws.state |= WS_ST_TO_ON_NET;
} else {
ws.to_mask = ripv1_mask_net(ws.to.sin_addr.s_addr, 0);
ws.to_net = ntohl(ws.to.sin_addr.s_addr) & ws.to_mask;
rt = rtfind(dst->sin_addr.s_addr);
if (rt)
ifp = rt->rt_ifp;
}
ws.npackets = 0;
if (flash)
ws.state |= WS_ST_FLASH;
if ((ws.ifp = ifp) == NULL) {
ws.metric = 1;
} else {
/* Adjust the advertised metric by the outgoing interface
* metric.
*/
ws.metric = ifp->int_metric+1;
}
ripv12_buf.rip.rip_vers = vers;
switch (type) {
case OUT_MULTICAST:
if (ifp->int_if_flags & IFF_MULTICAST)
v2buf.type = OUT_MULTICAST;
else
v2buf.type = NO_OUT_MULTICAST;
v12buf.type = OUT_BROADCAST;
break;
case OUT_QUERY:
ws.state |= WS_ST_QUERY;
/* fall through */
case OUT_BROADCAST:
case OUT_UNICAST:
v2buf.type = (vers == RIPv2) ? type : NO_OUT_RIPV2;
v12buf.type = type;
break;
case NO_OUT_MULTICAST:
case NO_OUT_RIPV2:
break; /* no output */
}
if (vers == RIPv2) {
/* full RIPv2 only if cannot be heard by RIPv1 listeners */
if (type != OUT_BROADCAST)
ws.state |= WS_ST_RIP2_ALL;
if ((ws.state & WS_ST_QUERY)
|| !(ws.state & WS_ST_TO_ON_NET)) {
ws.state |= (WS_ST_AG | WS_ST_SUPER_AG);
} else if (ifp == NULL || !(ifp->int_state & IS_NO_AG)) {
ws.state |= WS_ST_AG;
if (type != OUT_BROADCAST
&& (ifp == NULL
|| !(ifp->int_state & IS_NO_SUPER_AG)))
ws.state |= WS_ST_SUPER_AG;
}
}
ws.a = (vers == RIPv2) ? find_auth(ifp) : 0;
if (!passwd_ok && ws.a != NULL && ws.a->type == RIP_AUTH_PW)
ws.a = NULL;
clr_ws_buf(&v12buf,ws.a);
clr_ws_buf(&v2buf,ws.a);
/* Fake a default route if asked and if there is not already
* a better, real default route.
*/
if (supplier && (def_metric = ifp->int_d_metric) != 0) {
if (NULL == (rt = rtget(RIP_DEFAULT, 0))
|| rt->rt_metric+ws.metric >= def_metric) {
ws.state |= WS_ST_DEFAULT;
ag_check(0, 0, 0, 0, def_metric, def_metric,
0, 0, 0, supply_out);
} else {
def_metric = rt->rt_metric+ws.metric;
}
/* If both RIPv2 and the poor-man's router discovery
* kludge are on, arrange to advertise an extra
* default route via RIPv1.
*/
if ((ws.state & WS_ST_RIP2_ALL)
&& (ifp->int_state & IS_PM_RDISC)) {
ripv12_buf.rip.rip_vers = RIPv1;
v12buf.n->n_family = RIP_AF_INET;
v12buf.n->n_dst = htonl(RIP_DEFAULT);
v12buf.n->n_metric = htonl(def_metric);
v12buf.n++;
}
}
rn_walktree(rhead, walk_supply, 0);
ag_flush(0,0,supply_out);
/* Flush the packet buffers, provided they are not empty and
* do not contain only the password.
*/
if (v12buf.n != v12buf.base
&& (v12buf.n > v12buf.base+1
|| v12buf.base->n_family != RIP_AF_AUTH))
supply_write(&v12buf);
if (v2buf.n != v2buf.base
&& (v2buf.n > v2buf.base+1
|| v2buf.base->n_family != RIP_AF_AUTH))
supply_write(&v2buf);
/* If we sent nothing and this is an answer to a query, send
* an empty buffer.
*/
if (ws.npackets == 0
&& (ws.state & WS_ST_QUERY))
supply_write(&v12buf);
}
/* put an entry into the packet
*/
static void
supply_out(struct ag_info *ag)
{
int i;
naddr mask, v1_mask, dst_h, ddst_h = 0;
struct ws_buf *wb;
/* Skip this route if doing a flash update and it and the routes
* it aggregates have not changed recently.
*/
if (ag->ag_seqno < update_seqno
&& (ws.state & WS_ST_FLASH))
return;
dst_h = ag->ag_dst_h;
mask = ag->ag_mask;
v1_mask = ripv1_mask_host(htonl(dst_h),
(ws.state & WS_ST_TO_ON_NET) ? ws.ifp : 0);
i = 0;
/* If we are sending RIPv2 packets that cannot (or must not) be
* heard by RIPv1 listeners, do not worry about sub- or supernets.
* Subnets (from other networks) can only be sent via multicast.
* A pair of subnet routes might have been promoted so that they
* are legal to send by RIPv1.
* If RIPv1 is off, use the multicast buffer.
*/
if ((ws.state & WS_ST_RIP2_ALL)
|| ((ag->ag_state & AGS_RIPV2) && v1_mask != mask)) {
/* use the RIPv2-only buffer */
wb = &v2buf;
} else {
/* use the RIPv1-or-RIPv2 buffer */
wb = &v12buf;
/* Convert supernet route into corresponding set of network
* routes for RIPv1, but leave non-contiguous netmasks
* to ag_check().
*/
if (v1_mask > mask
&& mask + (mask & -mask) == 0) {
ddst_h = v1_mask & -v1_mask;
i = (v1_mask & ~mask)/ddst_h;
if (i > ws.gen_limit) {
/* Punt if we would have to generate an
* unreasonable number of routes.
*/
if (TRACECONTENTS)
trace_misc("sending %s-->%s as 1"
" instead of %d routes",
addrname(htonl(dst_h), mask,
1),
naddr_ntoa(ws.to.sin_addr
.s_addr),
i+1);
i = 0;
} else {
mask = v1_mask;
ws.gen_limit -= i;
}
}
}
do {
wb->n->n_family = RIP_AF_INET;
wb->n->n_dst = htonl(dst_h);
/* If the route is from router-discovery or we are
* shutting down, admit only a bad metric.
*/
wb->n->n_metric = ((stopint || ag->ag_metric < 1)
? HOPCNT_INFINITY
: ag->ag_metric);
wb->n->n_metric = htonl(wb->n->n_metric);
/* Any non-zero bits in the supposedly unused RIPv1 fields
* cause the old `routed` to ignore the route.
* That means the mask and so forth cannot be sent
* in the hybrid RIPv1/RIPv2 mode.
*/
if (ws.state & WS_ST_RIP2_ALL) {
if (ag->ag_nhop != 0
&& ((ws.state & WS_ST_QUERY)
|| (ag->ag_nhop != ws.ifp->int_addr
&& on_net(ag->ag_nhop,
ws.ifp->int_net,
ws.ifp->int_mask))))
wb->n->n_nhop = ag->ag_nhop;
wb->n->n_mask = htonl(mask);
wb->n->n_tag = ag->ag_tag;
}
dst_h += ddst_h;
if (++wb->n >= wb->lim)
supply_write(wb);
} while (i-- != 0);
}
/* ARGSUSED */
static int
walk_supply(struct radix_node *rn, __unused struct walkarg *argp)
{
#define RT ((struct rt_entry *)rn)
u_short ags;
char metric, pref;
naddr dst, nhop;
struct rt_spare *rts;
int i;
/* Do not advertise external remote interfaces or passive interfaces.
*/
if ((RT->rt_state & RS_IF)
&& RT->rt_ifp != 0
&& (RT->rt_ifp->int_state & IS_PASSIVE)
&& !(RT->rt_state & RS_MHOME))
return 0;
/* If being quiet about our ability to forward, then
* do not say anything unless responding to a query,
* except about our main interface.
*/
if (!supplier && !(ws.state & WS_ST_QUERY)
&& !(RT->rt_state & RS_MHOME))
return 0;
dst = RT->rt_dst;
/* do not collide with the fake default route */
if (dst == RIP_DEFAULT
&& (ws.state & WS_ST_DEFAULT))
return 0;
if (RT->rt_state & RS_NET_SYN) {
if (RT->rt_state & RS_NET_INT) {
/* Do not send manual synthetic network routes
* into the subnet.
*/
if (on_net(ws.to.sin_addr.s_addr,
ntohl(dst), RT->rt_mask))
return 0;
} else {
/* Do not send automatic synthetic network routes
* if they are not needed because no RIPv1 listeners
* can hear them.
*/
if (ws.state & WS_ST_RIP2_ALL)
return 0;
/* Do not send automatic synthetic network routes to
* the real subnet.
*/
if (on_net(ws.to.sin_addr.s_addr,
ntohl(dst), RT->rt_mask))
return 0;
}
nhop = 0;
} else {
/* Advertise the next hop if this is not a route for one
* of our interfaces and the next hop is on the same
* network as the target.
* The final determination is made by supply_out().
*/
if (!(RT->rt_state & RS_IF)
&& RT->rt_gate != myaddr
&& RT->rt_gate != loopaddr)
nhop = RT->rt_gate;
else
nhop = 0;
}
metric = RT->rt_metric;
ags = 0;
if (RT->rt_state & RS_MHOME) {
/* retain host route of multi-homed servers */
;
} else if (RT_ISHOST(RT)) {
/* We should always suppress (into existing network routes)
* the host routes for the local end of our point-to-point
* links.
* If we are suppressing host routes in general, then do so.
* Avoid advertising host routes onto their own network,
* where they should be handled by proxy-ARP.
*/
if ((RT->rt_state & RS_LOCAL)
|| ridhosts
|| on_net(dst, ws.to_net, ws.to_mask))
ags |= AGS_SUPPRESS;
/* Aggregate stray host routes into network routes if allowed.
* We cannot aggregate host routes into small network routes
* without confusing RIPv1 listeners into thinking the
* network routes are host routes.
*/
if ((ws.state & WS_ST_AG)
&& !(ws.state & WS_ST_RIP2_ALL))
ags |= AGS_AGGREGATE;
} else {
/* Always suppress network routes into other, existing
* network routes
*/
ags |= AGS_SUPPRESS;
/* Generate supernets if allowed.
* If we can be heard by RIPv1 systems, we will
* later convert back to ordinary nets.
* This unifies dealing with received supernets.
*/
if ((ws.state & WS_ST_AG)
&& ((RT->rt_state & RS_SUBNET)
|| (ws.state & WS_ST_SUPER_AG)))
ags |= AGS_AGGREGATE;
}
/* Do not send RIPv1 advertisements of subnets to other
* networks. If possible, multicast them by RIPv2.
*/
if ((RT->rt_state & RS_SUBNET)
&& !(ws.state & WS_ST_RIP2_ALL)
&& !on_net(dst, ws.to_std_net, ws.to_std_mask))
ags |= AGS_RIPV2 | AGS_AGGREGATE;
/* Do not send a route back to where it came from, except in
* response to a query. This is "split-horizon". That means not
* advertising back to the same network and so via the same interface.
*
* We want to suppress routes that might have been fragmented
* from this route by a RIPv1 router and sent back to us, and so we
* cannot forget this route here. Let the split-horizon route
* suppress the fragmented routes and then itself be forgotten.
*
* Include the routes for both ends of point-to-point interfaces
* among those suppressed by split-horizon, since the other side
* should knows them as well as we do.
*
* Notice spare routes with the same metric that we are about to
* advertise, to split the horizon on redundant, inactive paths.
*/
if (ws.ifp != 0
&& !(ws.state & WS_ST_QUERY)
&& (ws.state & WS_ST_TO_ON_NET)
&& (!(RT->rt_state & RS_IF)
|| ws.ifp->int_if_flags & IFF_POINTOPOINT)) {
for (rts = RT->rt_spares, i = NUM_SPARES; i != 0; i--, rts++) {
if (rts->rts_metric > metric
|| rts->rts_ifp != ws.ifp)
continue;
/* If we do not mark the route with AGS_SPLIT_HZ here,
* it will be poisoned-reverse, or advertised back
* toward its source with an infinite metric.
* If we have recently advertised the route with a
* better metric than we now have, then we should
* poison-reverse the route before suppressing it for
* split-horizon.
*
* In almost all cases, if there is no spare for the
* route then it is either old and dead or a brand
* new route. If it is brand new, there is no need
* for poison-reverse. If it is old and dead, it
* is already poisoned.
*/
if (RT->rt_poison_time < now_expire
|| RT->rt_poison_metric >= metric
|| RT->rt_spares[1].rts_gate == 0) {
ags |= AGS_SPLIT_HZ;
ags &= ~AGS_SUPPRESS;
}
metric = HOPCNT_INFINITY;
break;
}
}
/* Keep track of the best metric with which the
* route has been advertised recently.
*/
if (RT->rt_poison_metric >= metric
|| RT->rt_poison_time < now_expire) {
RT->rt_poison_time = now.tv_sec;
RT->rt_poison_metric = metric;
}
/* Adjust the outgoing metric by the cost of the link.
* Avoid aggregation when a route is counting to infinity.
*/
pref = RT->rt_poison_metric + ws.metric;
metric += ws.metric;
/* Do not advertise stable routes that will be ignored,
* unless we are answering a query.
* If the route recently was advertised with a metric that
* would have been less than infinity through this interface,
* we need to continue to advertise it in order to poison it.
*/
if (metric >= HOPCNT_INFINITY) {
if (!(ws.state & WS_ST_QUERY)
&& (pref >= HOPCNT_INFINITY
|| RT->rt_poison_time < now_garbage))
return 0;
metric = HOPCNT_INFINITY;
}
ag_check(dst, RT->rt_mask, 0, nhop, metric, pref,
RT->rt_seqno, RT->rt_tag, ags, supply_out);
return 0;
#undef RT
}
/* use configured parameters */
void
get_parms(struct interface *ifp)
{
static boolean_t warned_auth_in, warned_auth_out;
struct parm *parmp;
int i, num_passwds = 0;
if (ifp == NULL)
return;
/* get all relevant parameters */
for (parmp = parms; parmp != NULL; parmp = parmp->parm_next) {
if (parmp->parm_name[0] == '\0' ||
strcmp(ifp->int_name, parmp->parm_name) == 0 ||
(parmp->parm_name[0] == '\n' &&
on_net(ifp->int_addr,
parmp->parm_net, parmp->parm_mask))) {
/*
* This group of parameters is relevant,
* so get its settings
*/
ifp->int_state |= parmp->parm_int_state;
for (i = 0; i < MAX_AUTH_KEYS; i++) {
if (parmp->parm_auth[i].type == RIP_AUTH_NONE ||
num_passwds >= MAX_AUTH_KEYS)
break;
ifp->int_auth[num_passwds++] =
parmp->parm_auth[i];
}
if (parmp->parm_rdisc_pref != 0)
ifp->int_rdisc_pref = parmp->parm_rdisc_pref;
if (parmp->parm_rdisc_int != 0)
ifp->int_rdisc_int = parmp->parm_rdisc_int;
if (parmp->parm_d_metric != 0)
ifp->int_d_metric = parmp->parm_d_metric;
if (parmp->parm_ripout_addr != 0)
ifp->int_ripout_addr = parmp->parm_ripout_addr;
}
}
/*
* Set general defaults.
*
* Default poor-man's router discovery to a metric that will
* be heard by old versions of `routed`. They ignored received
* routes with metric 15.
*/
if ((ifp->int_state & IS_PM_RDISC) && ifp->int_d_metric == 0)
ifp->int_d_metric = FAKE_METRIC;
if (ifp->int_rdisc_int == 0)
ifp->int_rdisc_int = DEF_MAXADVERTISEINTERVAL;
if (!(ifp->int_if_flags & IFF_MULTICAST) &&
!(ifp->int_state & IS_REMOTE))
ifp->int_state |= IS_BCAST_RDISC;
if (ifp->int_if_flags & IFF_POINTOPOINT) {
ifp->int_state |= IS_BCAST_RDISC;
/*
* By default, point-to-point links should be passive
* about router-discovery for the sake of demand-dialing.
*/
if (!(ifp->int_state & GROUP_IS_SOL_OUT))
ifp->int_state |= IS_NO_SOL_OUT;
if (!(ifp->int_state & GROUP_IS_ADV_OUT))
ifp->int_state |= IS_NO_ADV_OUT;
}
if (0 != (ifp->int_state & (IS_PASSIVE | IS_REMOTE)))
ifp->int_state |= IS_NO_RDISC;
if (ifp->int_state & IS_PASSIVE)
ifp->int_state |= IS_NO_RIP;
if (!IS_RIP_IN_OFF(ifp->int_state) &&
ifp->int_auth[0].type != RIP_AUTH_NONE &&
!(ifp->int_state & IS_NO_RIPV1_IN) && !warned_auth_in) {
writelog(LOG_WARNING, "RIPv1 input via %s"
" will be accepted without authentication",
ifp->int_name);
warned_auth_in = _B_TRUE;
}
if (!IS_RIP_OUT_OFF(ifp->int_state) &&
ifp->int_auth[0].type != RIP_AUTH_NONE &&
!(ifp->int_state & IS_NO_RIPV1_OUT)) {
if (!warned_auth_out) {
writelog(LOG_WARNING, "RIPv1 output via %s"
" will be sent without authentication",
ifp->int_name);
warned_auth_out = _B_TRUE;
}
}
/*
* If not overriden by the rip_neighbor option, set the
* default address to which RIP packets will be sent on
* this interface.
*/
if (ifp->int_ripout_addr == 0) {
if (ifp->int_state & IS_REMOTE) {
/*
* By definition we always send RIP packets to
* the address assigned to a remote interface.
*/
ifp->int_ripout_addr = ifp->int_addr;
} else if ((ifp->int_state & IS_NO_RIPV1_OUT) &&
(ifp->int_if_flags & IFF_MULTICAST) &&
!(ifp->int_state & IS_NO_RIP_MCAST)) {
/*
* If the interface is being used for RIPv2
* and it supports multicast, and if the user
* has not explicitely turned off multicast
* RIP output, send to the all RIP routers
* multicast address.
*/
ifp->int_ripout_addr = htonl(INADDR_RIP_GROUP);
} else if (ifp->int_if_flags & IFF_POINTOPOINT) {
/*
* For point-to-point interfaces which don't
* fall into the two categories above, just
* send to the destination address of the
* interface.
*/
ifp->int_ripout_addr = ifp->int_dstaddr;
} else {
/* Otherwise, use the broadcast address. */
ifp->int_ripout_addr = ifp->int_brdaddr;
}
}
}