freebsd-dev/contrib/bsnmp/snmp_mibII/mibII_route.c
2012-10-18 13:46:26 +00:00

515 lines
12 KiB
C

/*
* Copyright (c) 2001-2003
* Fraunhofer Institute for Open Communication Systems (FhG Fokus).
* All rights reserved.
*
* Author: Harti Brandt <harti@freebsd.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $Begemot: bsnmp/snmp_mibII/mibII_route.c,v 1.9 2005/10/06 07:15:00 brandt_h Exp $
*
* Routing table
*/
#ifdef HAVE_SYS_TREE_H
#include <sys/tree.h>
#else
#include "tree.h"
#endif
#include "mibII.h"
#include "mibII_oid.h"
struct sroute {
RB_ENTRY(sroute) link;
uint32_t ifindex;
uint8_t index[13];
uint8_t type;
uint8_t proto;
};
RB_HEAD(sroutes, sroute) sroutes = RB_INITIALIZER(&sroutes);
RB_PROTOTYPE(sroutes, sroute, link, sroute_compare);
#define ROUTE_UPDATE_INTERVAL (100 * 60 * 10) /* 10 min */
static uint64_t route_tick;
static u_int route_total;
/*
* Compare two routes
*/
static int
sroute_compare(struct sroute *s1, struct sroute *s2)
{
return (memcmp(s1->index, s2->index, 13));
}
static void
sroute_index_append(struct asn_oid *oid, u_int sub, const struct sroute *s)
{
int i;
oid->len = sub + 13;
for (i = 0; i < 13; i++)
oid->subs[sub + i] = s->index[i];
}
#if 0
static void
sroute_print(const struct sroute *r)
{
u_int i;
for (i = 0; i < 13 - 1; i++)
printf("%u.", r->index[i]);
printf("%u proto=%u type=%u", r->index[i], r->proto, r->type);
}
#endif
/*
* process routing message
*/
void
mib_sroute_process(struct rt_msghdr *rtm, struct sockaddr *gw,
struct sockaddr *dst, struct sockaddr *mask)
{
struct sockaddr_in *in_dst, *in_gw;
struct in_addr in_mask;
struct mibif *ifp;
struct sroute key;
struct sroute *r, *r1;
in_addr_t ha;
if (dst == NULL || gw == NULL || dst->sa_family != AF_INET ||
gw->sa_family != AF_INET)
return;
in_dst = (struct sockaddr_in *)(void *)dst;
in_gw = (struct sockaddr_in *)(void *)gw;
if (rtm->rtm_flags & RTF_HOST)
in_mask.s_addr = 0xffffffff;
else if (mask == NULL || mask->sa_len == 0)
in_mask.s_addr = 0;
else
in_mask = ((struct sockaddr_in *)(void *)mask)->sin_addr;
/* build the index */
ha = ntohl(in_dst->sin_addr.s_addr);
key.index[0] = (ha >> 24) & 0xff;
key.index[1] = (ha >> 16) & 0xff;
key.index[2] = (ha >> 8) & 0xff;
key.index[3] = (ha >> 0) & 0xff;
ha = ntohl(in_mask.s_addr);
key.index[4] = (ha >> 24) & 0xff;
key.index[5] = (ha >> 16) & 0xff;
key.index[6] = (ha >> 8) & 0xff;
key.index[7] = (ha >> 0) & 0xff;
/* ToS */
key.index[8] = 0;
ha = ntohl(in_gw->sin_addr.s_addr);
key.index[9] = (ha >> 24) & 0xff;
key.index[10] = (ha >> 16) & 0xff;
key.index[11] = (ha >> 8) & 0xff;
key.index[12] = (ha >> 0) & 0xff;
if (rtm->rtm_type == RTM_DELETE) {
r = RB_FIND(sroutes, &sroutes, &key);
if (r == 0) {
#ifdef DEBUG_ROUTE
syslog(LOG_WARNING, "%s: DELETE: %u.%u.%u.%u "
"%u.%u.%u.%u %u %u.%u.%u.%u not found", __func__,
key.index[0], key.index[1], key.index[2],
key.index[3], key.index[4], key.index[5],
key.index[6], key.index[7], key.index[8],
key.index[9], key.index[10], key.index[11],
key.index[12]);
#endif
return;
}
RB_REMOVE(sroutes, &sroutes, r);
free(r);
route_total--;
#ifdef DEBUG_ROUTE
printf("%s: DELETE: %u.%u.%u.%u "
"%u.%u.%u.%u %u %u.%u.%u.%u\n", __func__,
key.index[0], key.index[1], key.index[2],
key.index[3], key.index[4], key.index[5],
key.index[6], key.index[7], key.index[8],
key.index[9], key.index[10], key.index[11],
key.index[12]);
#endif
return;
}
/* GET or ADD */
ifp = NULL;
if ((ifp = mib_find_if_sys(rtm->rtm_index)) == NULL) {
if (rtm->rtm_type == RTM_ADD) {
/* make it a get so the kernel fills the index */
mib_send_rtmsg(rtm, gw, dst, mask);
return;
}
mib_iflist_bad = 1;
}
if ((r = malloc(sizeof(*r))) == NULL) {
syslog(LOG_ERR, "%m");
return;
}
memcpy(r->index, key.index, sizeof(r->index));
r->ifindex = (ifp == NULL) ? 0 : ifp->index;
r->type = (rtm->rtm_flags & RTF_REJECT) ? 2 : 4;
/* cannot really know, what protocol it runs */
r->proto = (rtm->rtm_flags & RTF_LOCAL) ? 2 :
(rtm->rtm_flags & RTF_STATIC) ? 3 :
(rtm->rtm_flags & RTF_DYNAMIC) ? 4 : 10;
r1 = RB_INSERT(sroutes, &sroutes, r);
if (r1 != NULL) {
#ifdef DEBUG_ROUTE
syslog(LOG_WARNING, "%s: %u.%u.%u.%u "
"%u.%u.%u.%u %u %u.%u.%u.%u duplicate route", __func__,
key.index[0], key.index[1], key.index[2],
key.index[3], key.index[4], key.index[5],
key.index[6], key.index[7], key.index[8],
key.index[9], key.index[10], key.index[11],
key.index[12]);
#endif
r1->ifindex = r->ifindex;
r1->type = r->type;
r1->proto = r->proto;
free(r);
return;
}
route_total++;
#ifdef DEBUG_ROUTE
printf("%s: ADD/GET: %u.%u.%u.%u "
"%u.%u.%u.%u %u %u.%u.%u.%u\n", __func__,
key.index[0], key.index[1], key.index[2],
key.index[3], key.index[4], key.index[5],
key.index[6], key.index[7], key.index[8],
key.index[9], key.index[10], key.index[11],
key.index[12]);
#endif
}
int
mib_fetch_route(void)
{
u_char *rtab, *next;
size_t len;
struct sroute *r, *r1;
struct rt_msghdr *rtm;
struct sockaddr *addrs[RTAX_MAX];
if (route_tick != 0 && route_tick + ROUTE_UPDATE_INTERVAL > this_tick)
return (0);
/*
* Remove all routes
*/
r = RB_MIN(sroutes, &sroutes);
while (r != NULL) {
r1 = RB_NEXT(sroutes, &sroutes, r);
RB_REMOVE(sroutes, &sroutes, r);
free(r);
r = r1;
}
route_total = 0;
if ((rtab = mib_fetch_rtab(AF_INET, NET_RT_DUMP, 0, &len)) == NULL)
return (-1);
next = rtab;
for (next = rtab; next < rtab + len; next += rtm->rtm_msglen) {
rtm = (struct rt_msghdr *)(void *)next;
if (rtm->rtm_type != RTM_GET ||
!(rtm->rtm_flags & RTF_UP))
continue;
mib_extract_addrs(rtm->rtm_addrs, (u_char *)(rtm + 1), addrs);
mib_sroute_process(rtm, addrs[RTAX_GATEWAY], addrs[RTAX_DST],
addrs[RTAX_NETMASK]);
}
#if 0
u_int n = 0;
r = RB_MIN(sroutes, &sroutes);
while (r != NULL) {
printf("%u: ", n++);
sroute_print(r);
printf("\n");
r = RB_NEXT(sroutes, &sroutes, r);
}
#endif
free(rtab);
route_tick = get_ticks();
return (0);
}
/**
* Find a route in the table.
*/
static struct sroute *
sroute_get(const struct asn_oid *oid, u_int sub)
{
struct sroute key;
int i;
if (oid->len - sub != 13)
return (NULL);
for (i = 0; i < 13; i++)
key.index[i] = oid->subs[sub + i];
return (RB_FIND(sroutes, &sroutes, &key));
}
/**
* Find next route in the table. There is no such RB_ macro, so must
* dig into the innards of the RB stuff.
*/
static struct sroute *
sroute_getnext(struct asn_oid *oid, u_int sub)
{
u_int i;
int comp;
struct sroute key;
struct sroute *best;
struct sroute *s;
/*
* We now, that the OID is at least the tableEntry OID. If it is,
* the user wants the first route.
*/
if (oid->len == sub)
return (RB_MIN(sroutes, &sroutes));
/*
* This is also true for any index that consists of zeros and is
* shorter than the full index.
*/
if (oid->len < sub + 13) {
for (i = sub; i < oid->len; i++)
if (oid->subs[i] != 0)
break;
if (i == oid->len)
return (RB_MIN(sroutes, &sroutes));
/*
* Now if the index is too short, we fill it with zeros and then
* subtract one from the index. We can do this, because we now,
* that there is at least one index element that is not zero.
*/
for (i = oid->len; i < sub + 13; i++)
oid->subs[i] = 0;
for (i = sub + 13 - 1; i >= sub; i--) {
if (oid->subs[i] != 0) {
oid->subs[i]--;
break;
}
oid->subs[i] = ASN_MAXID;
}
oid->len = sub + 13;
}
/* build the index */
for (i = sub; i < sub + 13; i++)
key.index[i - sub] = oid->subs[i];
/* now find the element */
best = NULL;
s = RB_ROOT(&sroutes);
while (s != NULL) {
comp = sroute_compare(&key, s);
if (comp >= 0) {
/* The current element is smaller than what we search.
* Forget about it and move to the right subtree. */
s = RB_RIGHT(s, link);
continue;
}
/* the current element is larger than what we search.
* forget about the right subtree (its even larger), but
* the current element may be what we need. */
if (best == NULL || sroute_compare(s, best) < 0)
/* this one's better */
best = s;
s = RB_LEFT(s, link);
}
return (best);
}
/*
* Table
*/
int
op_route_table(struct snmp_context *ctx __unused, struct snmp_value *value,
u_int sub, u_int iidx __unused, enum snmp_op op)
{
struct sroute *r;
if (mib_fetch_route() == -1)
return (SNMP_ERR_GENERR);
switch (op) {
case SNMP_OP_GETNEXT:
if ((r = sroute_getnext(&value->var, sub)) == NULL)
return (SNMP_ERR_NOSUCHNAME);
sroute_index_append(&value->var, sub, r);
break;
case SNMP_OP_GET:
if ((r = sroute_get(&value->var, sub)) == NULL)
return (SNMP_ERR_NOSUCHNAME);
break;
case SNMP_OP_SET:
if ((r = sroute_get(&value->var, sub)) == NULL)
return (SNMP_ERR_NOSUCHNAME);
return (SNMP_ERR_NOT_WRITEABLE);
case SNMP_OP_ROLLBACK:
case SNMP_OP_COMMIT:
abort();
default:
abort();
}
switch (value->var.subs[sub - 1]) {
case LEAF_ipCidrRouteDest:
value->v.ipaddress[0] = r->index[0];
value->v.ipaddress[1] = r->index[1];
value->v.ipaddress[2] = r->index[2];
value->v.ipaddress[3] = r->index[3];
break;
case LEAF_ipCidrRouteMask:
value->v.ipaddress[0] = r->index[4];
value->v.ipaddress[1] = r->index[5];
value->v.ipaddress[2] = r->index[6];
value->v.ipaddress[3] = r->index[7];
break;
case LEAF_ipCidrRouteTos:
value->v.integer = r->index[8];
break;
case LEAF_ipCidrRouteNextHop:
value->v.ipaddress[0] = r->index[9];
value->v.ipaddress[1] = r->index[10];
value->v.ipaddress[2] = r->index[11];
value->v.ipaddress[3] = r->index[12];
break;
case LEAF_ipCidrRouteIfIndex:
value->v.integer = r->ifindex;
break;
case LEAF_ipCidrRouteType:
value->v.integer = r->type;
break;
case LEAF_ipCidrRouteProto:
value->v.integer = r->proto;
break;
case LEAF_ipCidrRouteAge:
value->v.integer = 0;
break;
case LEAF_ipCidrRouteInfo:
value->v.oid = oid_zeroDotZero;
break;
case LEAF_ipCidrRouteNextHopAS:
value->v.integer = 0;
break;
case LEAF_ipCidrRouteMetric1:
case LEAF_ipCidrRouteMetric2:
case LEAF_ipCidrRouteMetric3:
case LEAF_ipCidrRouteMetric4:
case LEAF_ipCidrRouteMetric5:
value->v.integer = -1;
break;
case LEAF_ipCidrRouteStatus:
value->v.integer = 1;
break;
}
return (SNMP_ERR_NOERROR);
}
/*
* scalars
*/
int
op_route(struct snmp_context *ctx __unused, struct snmp_value *value,
u_int sub, u_int iidx __unused, enum snmp_op op)
{
switch (op) {
case SNMP_OP_GETNEXT:
abort();
case SNMP_OP_GET:
break;
case SNMP_OP_SET:
return (SNMP_ERR_NOT_WRITEABLE);
case SNMP_OP_ROLLBACK:
case SNMP_OP_COMMIT:
abort();
}
if (mib_fetch_route() == -1)
return (SNMP_ERR_GENERR);
switch (value->var.subs[sub - 1]) {
case LEAF_ipCidrRouteNumber:
value->v.uint32 = route_total;
break;
}
return (SNMP_ERR_NOERROR);
}
RB_GENERATE(sroutes, sroute, link, sroute_compare);