freebsd-dev/contrib/bsnmp/snmp_mibII/mibII.c
2004-04-14 16:20:14 +00:00

1569 lines
34 KiB
C

/*
* Copyright (c) 2001-2003
* Fraunhofer Institute for Open Communication Systems (FhG Fokus).
* All rights reserved.
*
* Author: Harti Brandt <harti@freebsd.org>
*
* Redistribution of this software and documentation 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 or documentation 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.
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE AND DOCUMENTATION IS PROVIDED BY FRAUNHOFER FOKUS
* AND ITS 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
* FRAUNHOFER FOKUS OR ITS 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.c,v 1.18 2004/04/13 14:58:46 novo Exp $
*
* Implementation of the standard interfaces and ip MIB.
*/
#include "mibII.h"
#include "mibII_oid.h"
#include <net/if_types.h>
/*****************************/
/* our module */
static struct lmodule *module;
/* routing socket */
static int route;
static void *route_fd;
/* if-index allocator */
static u_int32_t next_if_index = 1;
/* re-fetch arp table */
static int update_arp;
static int in_update_arp;
/* OR registrations */
static u_int ifmib_reg;
static u_int ipmib_reg;
static u_int tcpmib_reg;
static u_int udpmib_reg;
static u_int ipForward_reg;
/*****************************/
/* list of all IP addresses */
struct mibifa_list mibifa_list = TAILQ_HEAD_INITIALIZER(mibifa_list);
/* list of all interfaces */
struct mibif_list mibif_list = TAILQ_HEAD_INITIALIZER(mibif_list);
/* list of dynamic interface names */
struct mibdynif_list mibdynif_list = SLIST_HEAD_INITIALIZER(mibdynif_list);
/* list of all interface index mappings */
struct mibindexmap_list mibindexmap_list = STAILQ_HEAD_INITIALIZER(mibindexmap_list);
/* list of all stacking entries */
struct mibifstack_list mibifstack_list = TAILQ_HEAD_INITIALIZER(mibifstack_list);
/* list of all receive addresses */
struct mibrcvaddr_list mibrcvaddr_list = TAILQ_HEAD_INITIALIZER(mibrcvaddr_list);
/* list of all NetToMedia entries */
struct mibarp_list mibarp_list = TAILQ_HEAD_INITIALIZER(mibarp_list);
/* number of interfaces */
int32_t mib_if_number;
/* last change of table */
u_int32_t mib_iftable_last_change;
/* last change of stack table */
u_int32_t mib_ifstack_last_change;
/* if this is set, one of our lists may be bad. refresh them when idle */
int mib_iflist_bad;
/* network socket */
int mib_netsock;
/* last time refreshed */
u_int32_t mibarpticks;
/* info on system clocks */
struct clockinfo clockinfo;
/* list of all New if registrations */
static struct newifreg_list newifreg_list = TAILQ_HEAD_INITIALIZER(newifreg_list);
/*****************************/
static const struct asn_oid oid_ifMIB = OIDX_ifMIB;
static const struct asn_oid oid_ipMIB = OIDX_ipMIB;
static const struct asn_oid oid_tcpMIB = OIDX_tcpMIB;
static const struct asn_oid oid_udpMIB = OIDX_udpMIB;
static const struct asn_oid oid_ipForward = OIDX_ipForward;
static const struct asn_oid oid_linkDown = OIDX_linkDown;
static const struct asn_oid oid_linkUp = OIDX_linkUp;
static const struct asn_oid oid_ifIndex = OIDX_ifIndex;
/*****************************/
/*
* Find an interface
*/
struct mibif *
mib_find_if(u_int idx)
{
struct mibif *ifp;
TAILQ_FOREACH(ifp, &mibif_list, link)
if (ifp->index == idx)
return (ifp);
return (NULL);
}
struct mibif *
mib_find_if_sys(u_int sysindex)
{
struct mibif *ifp;
TAILQ_FOREACH(ifp, &mibif_list, link)
if (ifp->sysindex == sysindex)
return (ifp);
return (NULL);
}
struct mibif *
mib_find_if_name(const char *name)
{
struct mibif *ifp;
TAILQ_FOREACH(ifp, &mibif_list, link)
if (strcmp(ifp->name, name) == 0)
return (ifp);
return (NULL);
}
/*
* Check whether an interface is dynamic. The argument may include the
* unit number. This assumes, that the name part does NOT contain digits.
*/
int
mib_if_is_dyn(const char *name)
{
size_t len;
struct mibdynif *d;
for (len = 0; name[len] != '\0' && isalpha(name[len]) ; len++)
;
SLIST_FOREACH(d, &mibdynif_list, link)
if (strlen(d->name) == len && strncmp(d->name, name, len) == 0)
return (1);
return (0);
}
/* set an interface name to dynamic mode */
void
mib_if_set_dyn(const char *name)
{
struct mibdynif *d;
SLIST_FOREACH(d, &mibdynif_list, link)
if (strcmp(name, d->name) == 0)
return;
if ((d = malloc(sizeof(*d))) == NULL)
err(1, NULL);
strcpy(d->name, name);
SLIST_INSERT_HEAD(&mibdynif_list, d, link);
}
/*
* register for interface creations
*/
int
mib_register_newif(int (*func)(struct mibif *), const struct lmodule *mod)
{
struct newifreg *reg;
TAILQ_FOREACH(reg, &newifreg_list, link)
if (reg->mod == mod) {
reg->func = func;
return (0);
}
if ((reg = malloc(sizeof(*reg))) == NULL) {
syslog(LOG_ERR, "newifreg: %m");
return (-1);
}
reg->mod = mod;
reg->func = func;
TAILQ_INSERT_TAIL(&newifreg_list, reg, link);
return (0);
}
void
mib_unregister_newif(const struct lmodule *mod)
{
struct newifreg *reg;
TAILQ_FOREACH(reg, &newifreg_list, link)
if (reg->mod == mod) {
TAILQ_REMOVE(&newifreg_list, reg, link);
free(reg);
return;
}
}
struct mibif *
mib_first_if(void)
{
return (TAILQ_FIRST(&mibif_list));
}
struct mibif *
mib_next_if(const struct mibif *ifp)
{
return (TAILQ_NEXT(ifp, link));
}
/*
* Change the admin status of an interface
*/
int
mib_if_admin(struct mibif *ifp, int up)
{
struct ifreq ifr;
strncpy(ifr.ifr_name, ifp->name, sizeof(ifr.ifr_name));
if (ioctl(mib_netsock, SIOCGIFFLAGS, &ifr) == -1) {
syslog(LOG_ERR, "SIOCGIFFLAGS(%s): %m", ifp->name);
return (-1);
}
if (up)
ifr.ifr_flags |= IFF_UP;
else
ifr.ifr_flags &= ~IFF_UP;
if (ioctl(mib_netsock, SIOCSIFFLAGS, &ifr) == -1) {
syslog(LOG_ERR, "SIOCSIFFLAGS(%s): %m", ifp->name);
return (-1);
}
(void)mib_fetch_ifmib(ifp);
return (0);
}
/*
* Generate a link up/down trap
*/
static void
link_trap(struct mibif *ifp, int up)
{
struct snmp_value ifindex;
ifindex.var = oid_ifIndex;
ifindex.var.subs[ifindex.var.len++] = ifp->index;
ifindex.syntax = SNMP_SYNTAX_INTEGER;
ifindex.v.integer = ifp->index;
snmp_send_trap(up ? &oid_linkUp : &oid_linkDown, &ifindex, NULL);
}
/*
* Fetch new MIB data.
*/
int
mib_fetch_ifmib(struct mibif *ifp)
{
int name[6];
size_t len;
void *newmib;
struct ifmibdata oldmib = ifp->mib;
name[0] = CTL_NET;
name[1] = PF_LINK;
name[2] = NETLINK_GENERIC;
name[3] = IFMIB_IFDATA;
name[4] = ifp->sysindex;
name[5] = IFDATA_GENERAL;
len = sizeof(ifp->mib);
if (sysctl(name, 6, &ifp->mib, &len, NULL, 0) == -1) {
if (errno != ENOENT)
syslog(LOG_WARNING, "sysctl(ifmib, %s) failed %m",
ifp->name);
return (-1);
}
if (ifp->trap_enable) {
if (!(oldmib.ifmd_flags & IFF_UP)) {
if (ifp->mib.ifmd_flags & IFF_UP)
link_trap(ifp, 1);
} else {
if (!(ifp->mib.ifmd_flags & IFF_UP))
link_trap(ifp, 0);
}
}
ifp->flags &= ~(MIBIF_HIGHSPEED | MIBIF_VERYHIGHSPEED);
if (ifp->mib.ifmd_data.ifi_baudrate > 20000000) {
ifp->flags |= MIBIF_HIGHSPEED;
if (ifp->mib.ifmd_data.ifi_baudrate > 650000000)
ifp->flags |= MIBIF_VERYHIGHSPEED;
}
/*
* linkspecific MIB
*/
name[5] = IFDATA_LINKSPECIFIC;
if (sysctl(name, 6, NULL, &len, NULL, 0) == -1) {
syslog(LOG_WARNING, "sysctl linkmib estimate (%s): %m",
ifp->name);
if (ifp->specmib != NULL) {
ifp->specmib = NULL;
ifp->specmiblen = 0;
}
goto out;
}
if (len == 0) {
if (ifp->specmib != NULL) {
ifp->specmib = NULL;
ifp->specmiblen = 0;
}
goto out;
}
if (ifp->specmiblen != len) {
if ((newmib = realloc(ifp->specmib, len)) == NULL) {
ifp->specmib = NULL;
ifp->specmiblen = 0;
goto out;
}
ifp->specmib = newmib;
ifp->specmiblen = len;
}
if (sysctl(name, 6, ifp->specmib, &len, NULL, 0) == -1) {
syslog(LOG_WARNING, "sysctl linkmib (%s): %m", ifp->name);
if (ifp->specmib != NULL) {
ifp->specmib = NULL;
ifp->specmiblen = 0;
}
}
out:
ifp->mibtick = get_ticks();
return (0);
}
/* find first/next address for a given interface */
struct mibifa *
mib_first_ififa(const struct mibif *ifp)
{
struct mibifa *ifa;
TAILQ_FOREACH(ifa, &mibifa_list, link)
if (ifp->index == ifa->ifindex)
return (ifa);
return (NULL);
}
struct mibifa *
mib_next_ififa(struct mibifa *ifa0)
{
struct mibifa *ifa;
ifa = ifa0;
while ((ifa = TAILQ_NEXT(ifa, link)) != NULL)
if (ifa->ifindex == ifa0->ifindex)
return (ifa);
return (NULL);
}
/*
* Allocate a new IFA
*/
static struct mibifa *
alloc_ifa(u_int ifindex, struct in_addr addr)
{
struct mibifa *ifa;
u_int32_t ha;
if ((ifa = malloc(sizeof(struct mibifa))) == NULL) {
syslog(LOG_ERR, "ifa: %m");
return (NULL);
}
ifa->inaddr = addr;
ifa->ifindex = ifindex;
ha = ntohl(ifa->inaddr.s_addr);
ifa->index.len = 4;
ifa->index.subs[0] = (ha >> 24) & 0xff;
ifa->index.subs[1] = (ha >> 16) & 0xff;
ifa->index.subs[2] = (ha >> 8) & 0xff;
ifa->index.subs[3] = (ha >> 0) & 0xff;
ifa->flags = 0;
ifa->inbcast.s_addr = 0;
ifa->inmask.s_addr = 0xffffffff;
INSERT_OBJECT_OID(ifa, &mibifa_list);
return (ifa);
}
/*
* Delete an interface address
*/
static void
destroy_ifa(struct mibifa *ifa)
{
TAILQ_REMOVE(&mibifa_list, ifa, link);
free(ifa);
}
/*
* Helper routine to extract the sockaddr structures from a routing
* socket message.
*/
void
mib_extract_addrs(int addrs, u_char *info, struct sockaddr **out)
{
u_int i;
for (i = 0; i < RTAX_MAX; i++) {
if ((addrs & (1 << i)) != 0) {
*out = (struct sockaddr *)info;
info += roundup((*out)->sa_len, sizeof(long));
} else
*out = NULL;
out++;
}
}
/*
* save the phys address of an interface. Handle receive address entries here.
*/
static void
get_physaddr(struct mibif *ifp, struct sockaddr_dl *sdl, u_char *ptr)
{
u_char *np;
struct mibrcvaddr *rcv;
if (sdl->sdl_alen == 0) {
/* no address */
if (ifp->physaddrlen != 0) {
if ((rcv = mib_find_rcvaddr(ifp->index, ifp->physaddr,
ifp->physaddrlen)) != NULL)
mib_rcvaddr_delete(rcv);
free(ifp->physaddr);
ifp->physaddr = NULL;
ifp->physaddrlen = 0;
}
return;
}
if (ifp->physaddrlen != sdl->sdl_alen) {
/* length changed */
if (ifp->physaddrlen) {
/* delete olf receive address */
if ((rcv = mib_find_rcvaddr(ifp->index, ifp->physaddr,
ifp->physaddrlen)) != NULL)
mib_rcvaddr_delete(rcv);
}
if ((np = realloc(ifp->physaddr, sdl->sdl_alen)) == NULL) {
free(ifp->physaddr);
ifp->physaddr = NULL;
ifp->physaddrlen = 0;
return;
}
ifp->physaddr = np;
ifp->physaddrlen = sdl->sdl_alen;
} else if (memcmp(ifp->physaddr, ptr, ifp->physaddrlen) == 0) {
/* no change */
return;
} else {
/* address changed */
/* delete olf receive address */
if ((rcv = mib_find_rcvaddr(ifp->index, ifp->physaddr,
ifp->physaddrlen)) != NULL)
mib_rcvaddr_delete(rcv);
}
memcpy(ifp->physaddr, ptr, ifp->physaddrlen);
/* make new receive address */
if ((rcv = mib_rcvaddr_create(ifp, ifp->physaddr, ifp->physaddrlen)) != NULL)
rcv->flags |= MIBRCVADDR_HW;
}
/*
* Free an interface
*/
static void
mibif_free(struct mibif *ifp)
{
struct mibindexmap *map;
struct mibifa *ifa, *ifa1;
struct mibrcvaddr *rcv, *rcv1;
struct mibarp *at, *at1;
if (ifp->xnotify != NULL)
(*ifp->xnotify)(ifp, MIBIF_NOTIFY_DESTROY, ifp->xnotify_data);
(void)mib_ifstack_delete(ifp, NULL);
(void)mib_ifstack_delete(NULL, ifp);
TAILQ_REMOVE(&mibif_list, ifp, link);
if (ifp->physaddr != NULL)
free(ifp->physaddr);
if (ifp->specmib != NULL)
free(ifp->specmib);
STAILQ_FOREACH(map, &mibindexmap_list, link)
if (map->mibif == ifp) {
map->mibif = NULL;
break;
}
/* purge interface addresses */
ifa = TAILQ_FIRST(&mibifa_list);
while (ifa != NULL) {
ifa1 = TAILQ_NEXT(ifa, link);
if (ifa->ifindex == ifp->index)
destroy_ifa(ifa);
ifa = ifa1;
}
/* purge receive addresses */
rcv = TAILQ_FIRST(&mibrcvaddr_list);
while (rcv != NULL) {
rcv1 = TAILQ_NEXT(rcv, link);
if (rcv->ifindex == ifp->index)
mib_rcvaddr_delete(rcv);
rcv = rcv1;
}
/* purge ARP entries */
at = TAILQ_FIRST(&mibarp_list);
while (at != NULL) {
at1 = TAILQ_NEXT(at, link);
if (at->index.subs[0] == ifp->index)
mib_arp_delete(at);
at = at1;
}
free(ifp);
mib_if_number--;
mib_iftable_last_change = this_tick;
}
/*
* Create a new interface
*/
static struct mibif *
mibif_create(u_int sysindex, const char *name)
{
struct mibif *ifp;
struct mibindexmap *map;
if ((ifp = malloc(sizeof(*ifp))) == NULL) {
syslog(LOG_WARNING, "%s: %m", __func__);
return (NULL);
}
memset(ifp, 0, sizeof(*ifp));
ifp->sysindex = sysindex;
strcpy(ifp->name, name);
strcpy(ifp->descr, name);
map = NULL;
if (!mib_if_is_dyn(ifp->name)) {
/* non-dynamic. look whether we know the interface */
STAILQ_FOREACH(map, &mibindexmap_list, link)
if (strcmp(map->name, ifp->name) == 0) {
ifp->index = map->ifindex;
map->mibif = ifp;
break;
}
/* assume it has a connector if it is not dynamic */
ifp->has_connector = 1;
ifp->trap_enable = 1;
}
if (map == NULL) {
/* new interface - get new index */
if (next_if_index > 0x7fffffff)
errx(1, "ifindex wrap");
if ((map = malloc(sizeof(*map))) == NULL) {
syslog(LOG_ERR, "ifmap: %m");
free(ifp);
return (NULL);
}
map->ifindex = next_if_index++;
map->sysindex = ifp->sysindex;
strcpy(map->name, ifp->name);
map->mibif = ifp;
STAILQ_INSERT_TAIL(&mibindexmap_list, map, link);
} else {
/* re-instantiate. Introduce a counter discontinuity */
ifp->counter_disc = get_ticks();
}
ifp->index = map->ifindex;
INSERT_OBJECT_INT(ifp, &mibif_list);
mib_if_number++;
mib_iftable_last_change = this_tick;
/* instantiate default ifStack entries */
(void)mib_ifstack_create(ifp, NULL);
(void)mib_ifstack_create(NULL, ifp);
return (ifp);
}
/*
* Inform all interested parties about a new interface
*/
static void
notify_newif(struct mibif *ifp)
{
struct newifreg *reg;
TAILQ_FOREACH(reg, &newifreg_list, link)
if ((*reg->func)(ifp))
return;
}
/*
* This is called for new interfaces after we have fetched the interface
* MIB. If this is a broadcast interface try to guess the broadcast address
* depending on the interface type.
*/
static void
check_llbcast(struct mibif *ifp)
{
static u_char ether_bcast[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
static u_char arcnet_bcast = 0;
struct mibrcvaddr *rcv;
if (!(ifp->mib.ifmd_flags & IFF_BROADCAST))
return;
switch (ifp->mib.ifmd_data.ifi_type) {
case IFT_ETHER:
case IFT_FDDI:
case IFT_ISO88025:
if (mib_find_rcvaddr(ifp->index, ether_bcast, 6) == NULL &&
(rcv = mib_rcvaddr_create(ifp, ether_bcast, 6)) != NULL)
rcv->flags |= MIBRCVADDR_BCAST;
break;
case IFT_ARCNET:
if (mib_find_rcvaddr(ifp->index, &arcnet_bcast, 1) == NULL &&
(rcv = mib_rcvaddr_create(ifp, &arcnet_bcast, 1)) != NULL)
rcv->flags |= MIBRCVADDR_BCAST;
break;
}
}
/*
* Retrieve the current interface list from the system.
*/
void
mib_refresh_iflist(void)
{
struct mibif *ifp, *ifp1;
size_t len;
u_short idx;
int name[6];
int count;
struct ifmibdata mib;
TAILQ_FOREACH(ifp, &mibif_list, link)
ifp->flags &= ~MIBIF_FOUND;
len = sizeof(count);
if (sysctlbyname("net.link.generic.system.ifcount", &count, &len,
NULL, 0) == -1) {
syslog(LOG_ERR, "ifcount: %m");
return;
}
name[0] = CTL_NET;
name[1] = PF_LINK;
name[2] = NETLINK_GENERIC;
name[3] = IFMIB_IFDATA;
name[5] = IFDATA_GENERAL;
for (idx = 1; idx <= count; idx++) {
name[4] = idx;
len = sizeof(mib);
if (sysctl(name, 6, &mib, &len, NULL, 0) == -1) {
if (errno == ENOENT)
continue;
syslog(LOG_ERR, "ifmib(%u): %m", idx);
return;
}
if ((ifp = mib_find_if_sys(idx)) != NULL) {
ifp->flags |= MIBIF_FOUND;
continue;
}
/* Unknown interface - create */
if ((ifp = mibif_create(idx, mib.ifmd_name)) != NULL) {
ifp->flags |= MIBIF_FOUND;
(void)mib_fetch_ifmib(ifp);
check_llbcast(ifp);
notify_newif(ifp);
}
}
/*
* Purge interfaces that disappeared
*/
ifp = TAILQ_FIRST(&mibif_list);
while (ifp != NULL) {
ifp1 = TAILQ_NEXT(ifp, link);
if (!(ifp->flags & MIBIF_FOUND))
mibif_free(ifp);
ifp = ifp1;
}
}
/*
* Find an interface address
*/
struct mibifa *
mib_find_ifa(struct in_addr addr)
{
struct mibifa *ifa;
TAILQ_FOREACH(ifa, &mibifa_list, link)
if (ifa->inaddr.s_addr == addr.s_addr)
return (ifa);
return (NULL);
}
/*
* Process a new ARP entry
*/
static void
process_arp(const struct rt_msghdr *rtm, const struct sockaddr_dl *sdl,
const struct sockaddr_in *sa)
{
struct mibif *ifp;
struct mibarp *at;
/* IP arp table entry */
if (sdl->sdl_alen == 0) {
update_arp = 1;
return;
}
if ((ifp = mib_find_if_sys(sdl->sdl_index)) == NULL)
return;
/* have a valid entry */
if ((at = mib_find_arp(ifp, sa->sin_addr)) == NULL &&
(at = mib_arp_create(ifp, sa->sin_addr,
sdl->sdl_data + sdl->sdl_nlen, sdl->sdl_alen)) == NULL)
return;
if (rtm->rtm_rmx.rmx_expire == 0)
at->flags |= MIBARP_PERM;
else
at->flags &= ~MIBARP_PERM;
at->flags |= MIBARP_FOUND;
}
/*
* Handle a routing socket message.
*/
static void
handle_rtmsg(struct rt_msghdr *rtm)
{
struct sockaddr *addrs[RTAX_MAX];
struct if_msghdr *ifm;
struct ifa_msghdr *ifam;
struct ifma_msghdr *ifmam;
#ifdef RTM_IFANNOUNCE
struct if_announcemsghdr *ifan;
#endif
struct mibif *ifp;
struct sockaddr_dl *sdl;
struct sockaddr_in *sa;
struct mibifa *ifa;
struct mibrcvaddr *rcv;
u_char *ptr;
if (rtm->rtm_version != RTM_VERSION) {
syslog(LOG_ERR, "Bogus RTM version %u", rtm->rtm_version);
return;
}
switch (rtm->rtm_type) {
case RTM_NEWADDR:
ifam = (struct ifa_msghdr *)rtm;
mib_extract_addrs(ifam->ifam_addrs, (u_char *)(ifam + 1), addrs);
if (addrs[RTAX_IFA] == NULL || addrs[RTAX_NETMASK] == NULL)
break;
sa = (struct sockaddr_in *)(void *)addrs[RTAX_IFA];
if ((ifa = mib_find_ifa(sa->sin_addr)) == NULL) {
/* unknown address */
if ((ifp = mib_find_if_sys(ifam->ifam_index)) == NULL) {
syslog(LOG_WARNING, "RTM_NEWADDR for unknown "
"interface %u", ifam->ifam_index);
break;
}
if ((ifa = alloc_ifa(ifp->index, sa->sin_addr)) == NULL)
break;
}
sa = (struct sockaddr_in *)(void *)addrs[RTAX_NETMASK];
ifa->inmask = sa->sin_addr;
if (addrs[RTAX_BRD] != NULL) {
sa = (struct sockaddr_in *)(void *)addrs[RTAX_BRD];
ifa->inbcast = sa->sin_addr;
}
ifa->flags |= MIBIFA_FOUND;
break;
case RTM_DELADDR:
ifam = (struct ifa_msghdr *)rtm;
mib_extract_addrs(ifam->ifam_addrs, (u_char *)(ifam + 1), addrs);
if (addrs[RTAX_IFA] == NULL)
break;
sa = (struct sockaddr_in *)(void *)addrs[RTAX_IFA];
if ((ifa = mib_find_ifa(sa->sin_addr)) != NULL) {
ifa->flags |= MIBIFA_FOUND;
if (!(ifa->flags & MIBIFA_DESTROYED))
destroy_ifa(ifa);
}
break;
case RTM_NEWMADDR:
ifmam = (struct ifma_msghdr *)rtm;
mib_extract_addrs(ifmam->ifmam_addrs, (u_char *)(ifmam + 1), addrs);
if (addrs[RTAX_IFA] == NULL ||
addrs[RTAX_IFA]->sa_family != AF_LINK)
break;
sdl = (struct sockaddr_dl *)(void *)addrs[RTAX_IFA];
if ((rcv = mib_find_rcvaddr(sdl->sdl_index,
sdl->sdl_data + sdl->sdl_nlen, sdl->sdl_alen)) == NULL) {
/* unknown address */
if ((ifp = mib_find_if_sys(sdl->sdl_index)) == NULL) {
syslog(LOG_WARNING, "RTM_NEWMADDR for unknown "
"interface %u", sdl->sdl_index);
break;
}
if ((rcv = mib_rcvaddr_create(ifp,
sdl->sdl_data + sdl->sdl_nlen, sdl->sdl_alen)) == NULL)
break;
rcv->flags |= MIBRCVADDR_VOLATILE;
}
rcv->flags |= MIBRCVADDR_FOUND;
break;
case RTM_DELMADDR:
ifmam = (struct ifma_msghdr *)rtm;
mib_extract_addrs(ifmam->ifmam_addrs, (u_char *)(ifmam + 1), addrs);
if (addrs[RTAX_IFA] == NULL ||
addrs[RTAX_IFA]->sa_family != AF_LINK)
break;
sdl = (struct sockaddr_dl *)(void *)addrs[RTAX_IFA];
if ((rcv = mib_find_rcvaddr(sdl->sdl_index,
sdl->sdl_data + sdl->sdl_nlen, sdl->sdl_alen)) != NULL)
mib_rcvaddr_delete(rcv);
break;
case RTM_IFINFO:
ifm = (struct if_msghdr *)rtm;
mib_extract_addrs(ifm->ifm_addrs, (u_char *)(ifm + 1), addrs);
if ((ifp = mib_find_if_sys(ifm->ifm_index)) == NULL)
break;
if (addrs[RTAX_IFP] != NULL &&
addrs[RTAX_IFP]->sa_family == AF_LINK) {
sdl = (struct sockaddr_dl *)(void *)addrs[RTAX_IFP];
ptr = sdl->sdl_data + sdl->sdl_nlen;
get_physaddr(ifp, sdl, ptr);
}
(void)mib_fetch_ifmib(ifp);
break;
#ifdef RTM_IFANNOUNCE
case RTM_IFANNOUNCE:
ifan = (struct if_announcemsghdr *)rtm;
ifp = mib_find_if_sys(ifan->ifan_index);
switch (ifan->ifan_what) {
case IFAN_ARRIVAL:
if (ifp == NULL && (ifp = mibif_create(ifan->ifan_index,
ifan->ifan_name)) != NULL) {
(void)mib_fetch_ifmib(ifp);
check_llbcast(ifp);
notify_newif(ifp);
}
break;
case IFAN_DEPARTURE:
if (ifp != NULL)
mibif_free(ifp);
break;
}
break;
#endif
case RTM_GET:
mib_extract_addrs(rtm->rtm_addrs, (u_char *)(rtm + 1), addrs);
if (rtm->rtm_flags & RTF_LLINFO) {
if (addrs[RTAX_DST] == NULL ||
addrs[RTAX_GATEWAY] == NULL ||
addrs[RTAX_DST]->sa_family != AF_INET ||
addrs[RTAX_GATEWAY]->sa_family != AF_LINK)
break;
process_arp(rtm,
(struct sockaddr_dl *)(void *)addrs[RTAX_GATEWAY],
(struct sockaddr_in *)(void *)addrs[RTAX_DST]);
}
break;
case RTM_ADD:
mib_extract_addrs(rtm->rtm_addrs, (u_char *)(rtm + 1), addrs);
if (rtm->rtm_flags & RTF_LLINFO) {
if (addrs[RTAX_DST] == NULL ||
addrs[RTAX_GATEWAY] == NULL ||
addrs[RTAX_DST]->sa_family != AF_INET ||
addrs[RTAX_GATEWAY]->sa_family != AF_LINK)
break;
process_arp(rtm,
(struct sockaddr_dl *)(void *)addrs[RTAX_GATEWAY],
(struct sockaddr_in *)(void *)addrs[RTAX_DST]);
}
break;
}
}
/*
* Fetch the routing table via sysctl
*/
u_char *
mib_fetch_rtab(int af, int info, int arg, size_t *lenp)
{
int name[6];
u_char *buf;
name[0] = CTL_NET;
name[1] = PF_ROUTE;
name[2] = 0;
name[3] = af;
name[4] = info;
name[5] = arg;
*lenp = 0;
if (sysctl(name, 6, NULL, lenp, NULL, 0) == -1) {
syslog(LOG_ERR, "sysctl estimate (%d,%d,%d,%d,%d,%d): %m",
name[0], name[1], name[2], name[3], name[4], name[5]);
return (NULL);
}
if (*lenp == 0)
return (NULL);
if ((buf = malloc(*lenp)) == NULL) {
syslog(LOG_ERR, "sysctl buffer: %m");
return (NULL);
}
if (sysctl(name, 6, buf, lenp, NULL, 0) == -1) {
syslog(LOG_ERR, "sysctl get: %m");
free(buf);
return (NULL);
}
return (buf);
}
/*
* Update the following info: interface, interface addresses, interface
* receive addresses, arp-table.
* This does not change the interface list itself.
*/
static void
update_ifa_info(void)
{
u_char *buf, *next;
struct rt_msghdr *rtm;
struct mibifa *ifa, *ifa1;
struct mibrcvaddr *rcv, *rcv1;
size_t needed;
static const int infos[][3] = {
{ 0, NET_RT_IFLIST, 0 },
#ifdef NET_RT_IFMALIST
{ AF_LINK, NET_RT_IFMALIST, 0 },
#endif
};
u_int i;
TAILQ_FOREACH(ifa, &mibifa_list, link)
ifa->flags &= ~MIBIFA_FOUND;
TAILQ_FOREACH(rcv, &mibrcvaddr_list, link)
rcv->flags &= ~MIBRCVADDR_FOUND;
for (i = 0; i < sizeof(infos) / sizeof(infos[0]); i++) {
if ((buf = mib_fetch_rtab(infos[i][0], infos[i][1], infos[i][2],
&needed)) == NULL)
continue;
next = buf;
while (next < buf + needed) {
rtm = (struct rt_msghdr *)(void *)next;
next += rtm->rtm_msglen;
handle_rtmsg(rtm);
}
free(buf);
}
/*
* Purge the address list of unused entries. These may happen for
* interface aliases that are on the same subnet. We don't receive
* routing socket messages for them.
*/
ifa = TAILQ_FIRST(&mibifa_list);
while (ifa != NULL) {
ifa1 = TAILQ_NEXT(ifa, link);
if (!(ifa->flags & MIBIFA_FOUND))
destroy_ifa(ifa);
ifa = ifa1;
}
rcv = TAILQ_FIRST(&mibrcvaddr_list);
while (rcv != NULL) {
rcv1 = TAILQ_NEXT(rcv, link);
if (!(rcv->flags & (MIBRCVADDR_FOUND | MIBRCVADDR_BCAST |
MIBRCVADDR_HW)))
mib_rcvaddr_delete(rcv);
rcv = rcv1;
}
}
/*
* Update arp table
*/
void
mib_arp_update(void)
{
struct mibarp *at, *at1;
size_t needed;
u_char *buf, *next;
struct rt_msghdr *rtm;
if (in_update_arp)
return; /* Aaargh */
in_update_arp = 1;
TAILQ_FOREACH(at, &mibarp_list, link)
at->flags &= ~MIBARP_FOUND;
if ((buf = mib_fetch_rtab(AF_INET, NET_RT_FLAGS, RTF_LLINFO, &needed)) == NULL) {
in_update_arp = 0;
return;
}
next = buf;
while (next < buf + needed) {
rtm = (struct rt_msghdr *)(void *)next;
next += rtm->rtm_msglen;
handle_rtmsg(rtm);
}
free(buf);
at = TAILQ_FIRST(&mibarp_list);
while (at != NULL) {
at1 = TAILQ_NEXT(at, link);
if (!(at->flags & MIBARP_FOUND))
mib_arp_delete(at);
at = at1;
}
mibarpticks = get_ticks();
update_arp = 0;
in_update_arp = 0;
}
/*
* Intput on the routing socket.
*/
static void
route_input(int fd, void *udata __unused)
{
u_char buf[1024 * 16];
ssize_t n;
struct rt_msghdr *rtm;
if ((n = read(fd, buf, sizeof(buf))) == -1)
err(1, "read(rt_socket)");
if (n == 0)
errx(1, "EOF on rt_socket");
rtm = (struct rt_msghdr *)(void *)buf;
if ((size_t)n != rtm->rtm_msglen)
errx(1, "n=%zu, rtm_msglen=%u", (size_t)n, rtm->rtm_msglen);
handle_rtmsg(rtm);
}
/*
* execute and SIOCAIFADDR
*/
static int
siocaifaddr(char *ifname, struct in_addr addr, struct in_addr mask,
struct in_addr bcast)
{
struct ifaliasreq addreq;
struct sockaddr_in *sa;
memset(&addreq, 0, sizeof(addreq));
strncpy(addreq.ifra_name, ifname, sizeof(addreq.ifra_name));
sa = (struct sockaddr_in *)(void *)&addreq.ifra_addr;
sa->sin_family = AF_INET;
sa->sin_len = sizeof(*sa);
sa->sin_addr = addr;
sa = (struct sockaddr_in *)(void *)&addreq.ifra_mask;
sa->sin_family = AF_INET;
sa->sin_len = sizeof(*sa);
sa->sin_addr = mask;
sa = (struct sockaddr_in *)(void *)&addreq.ifra_broadaddr;
sa->sin_family = AF_INET;
sa->sin_len = sizeof(*sa);
sa->sin_addr = bcast;
return (ioctl(mib_netsock, SIOCAIFADDR, &addreq));
}
/*
* Exececute a SIOCDIFADDR
*/
static int
siocdifaddr(const char *ifname, struct in_addr addr)
{
struct ifreq delreq;
struct sockaddr_in *sa;
memset(&delreq, 0, sizeof(delreq));
strncpy(delreq.ifr_name, ifname, sizeof(delreq.ifr_name));
sa = (struct sockaddr_in *)(void *)&delreq.ifr_addr;
sa->sin_family = AF_INET;
sa->sin_len = sizeof(*sa);
sa->sin_addr = addr;
return (ioctl(mib_netsock, SIOCDIFADDR, &delreq));
}
/*
* Verify an interface address without fetching the entire list
*/
static int
verify_ifa(const char *name, struct mibifa *ifa)
{
struct ifreq req;
struct sockaddr_in *sa;
memset(&req, 0, sizeof(req));
strncpy(req.ifr_name, name, sizeof(req.ifr_name));
sa = (struct sockaddr_in *)(void *)&req.ifr_addr;
sa->sin_family = AF_INET;
sa->sin_len = sizeof(*sa);
sa->sin_addr = ifa->inaddr;
if (ioctl(mib_netsock, SIOCGIFADDR, &req) == -1)
return (-1);
if (ifa->inaddr.s_addr != sa->sin_addr.s_addr) {
syslog(LOG_ERR, "%s: address mismatch", __func__);
return (-1);
}
if (ioctl(mib_netsock, SIOCGIFNETMASK, &req) == -1)
return (-1);
if (ifa->inmask.s_addr != sa->sin_addr.s_addr) {
syslog(LOG_ERR, "%s: netmask mismatch", __func__);
return (-1);
}
return (0);
}
/*
* Restore a deleted interface address. Don't wait for the routing socket
* to update us.
*/
void
mib_undestroy_ifa(struct mibifa *ifa)
{
struct mibif *ifp;
if ((ifp = mib_find_if(ifa->ifindex)) == NULL)
/* keep it destroyed */
return;
if (siocaifaddr(ifp->name, ifa->inaddr, ifa->inmask, ifa->inbcast))
/* keep it destroyed */
return;
ifa->flags &= ~MIBIFA_DESTROYED;
}
/*
* Destroy an interface address
*/
int
mib_destroy_ifa(struct mibifa *ifa)
{
struct mibif *ifp;
if ((ifp = mib_find_if(ifa->ifindex)) == NULL) {
/* ups. */
mib_iflist_bad = 1;
return (-1);
}
if (siocdifaddr(ifp->name, ifa->inaddr)) {
/* ups. */
syslog(LOG_ERR, "SIOCDIFADDR: %m");
mib_iflist_bad = 1;
return (-1);
}
ifa->flags |= MIBIFA_DESTROYED;
return (0);
}
/*
* Rollback the modification of an address. Don't bother to wait for
* the routing socket.
*/
void
mib_unmodify_ifa(struct mibifa *ifa)
{
struct mibif *ifp;
if ((ifp = mib_find_if(ifa->ifindex)) == NULL) {
/* ups. */
mib_iflist_bad = 1;
return;
}
if (siocaifaddr(ifp->name, ifa->inaddr, ifa->inmask, ifa->inbcast)) {
/* ups. */
mib_iflist_bad = 1;
return;
}
}
/*
* Modify an IFA.
*/
int
mib_modify_ifa(struct mibifa *ifa)
{
struct mibif *ifp;
if ((ifp = mib_find_if(ifa->ifindex)) == NULL) {
/* ups. */
mib_iflist_bad = 1;
return (-1);
}
if (siocaifaddr(ifp->name, ifa->inaddr, ifa->inmask, ifa->inbcast)) {
/* ups. */
mib_iflist_bad = 1;
return (-1);
}
if (verify_ifa(ifp->name, ifa)) {
/* ups. */
mib_iflist_bad = 1;
return (-1);
}
return (0);
}
/*
* Destroy a freshly created interface address. Don't bother to wait for
* the routing socket.
*/
void
mib_uncreate_ifa(struct mibifa *ifa)
{
struct mibif *ifp;
if ((ifp = mib_find_if(ifa->ifindex)) == NULL) {
/* ups. */
mib_iflist_bad = 1;
return;
}
if (siocdifaddr(ifp->name, ifa->inaddr)) {
/* ups. */
mib_iflist_bad = 1;
return;
}
destroy_ifa(ifa);
}
/*
* Create a new ifa and verify it
*/
struct mibifa *
mib_create_ifa(u_int ifindex, struct in_addr addr, struct in_addr mask,
struct in_addr bcast)
{
struct mibif *ifp;
struct mibifa *ifa;
if ((ifp = mib_find_if(ifindex)) == NULL)
return (NULL);
if ((ifa = alloc_ifa(ifindex, addr)) == NULL)
return (NULL);
ifa->inmask = mask;
ifa->inbcast = bcast;
if (siocaifaddr(ifp->name, ifa->inaddr, ifa->inmask, ifa->inbcast)) {
syslog(LOG_ERR, "%s: %m", __func__);
destroy_ifa(ifa);
return (NULL);
}
if (verify_ifa(ifp->name, ifa)) {
destroy_ifa(ifa);
return (NULL);
}
return (ifa);
}
/*
* Get all cloning interfaces and make them dynamic.
* Hah! Whe should probably do this on a periodic basis (XXX).
*/
static void
get_cloners(void)
{
struct if_clonereq req;
char *buf, *cp;
int i;
memset(&req, 0, sizeof(req));
if (ioctl(mib_netsock, SIOCIFGCLONERS, &req) == -1) {
syslog(LOG_ERR, "get cloners: %m");
return;
}
if ((buf = malloc(req.ifcr_total * IFNAMSIZ)) == NULL) {
syslog(LOG_ERR, "%m");
return;
}
req.ifcr_count = req.ifcr_total;
req.ifcr_buffer = buf;
if (ioctl(mib_netsock, SIOCIFGCLONERS, &req) == -1) {
syslog(LOG_ERR, "get cloners: %m");
free(buf);
return;
}
for (cp = buf, i = 0; i < req.ifcr_total; i++, cp += IFNAMSIZ)
mib_if_set_dyn(cp);
free(buf);
}
/*
* Idle function
*/
static void
mibII_idle(void)
{
struct mibifa *ifa;
if (mib_iflist_bad) {
TAILQ_FOREACH(ifa, &mibifa_list, link)
ifa->flags &= ~MIBIFA_DESTROYED;
/* assume, that all cloning interfaces are dynamic */
get_cloners();
mib_refresh_iflist();
update_ifa_info();
mib_arp_update();
mib_iflist_bad = 0;
}
if (update_arp)
mib_arp_update();
}
/*
* Start the module
*/
static void
mibII_start(void)
{
if ((route_fd = fd_select(route, route_input, NULL, module)) == NULL) {
syslog(LOG_ERR, "fd_select(route): %m");
return;
}
mib_refresh_iflist();
update_ifa_info();
mib_arp_update();
mib_iftable_last_change = 0;
mib_ifstack_last_change = 0;
ifmib_reg = or_register(&oid_ifMIB,
"The MIB module to describe generic objects for network interface"
" sub-layers.", module);
ipmib_reg = or_register(&oid_ipMIB,
"The MIB module for managing IP and ICMP implementations, but "
"excluding their management of IP routes.", module);
tcpmib_reg = or_register(&oid_tcpMIB,
"The MIB module for managing TCP implementations.", module);
udpmib_reg = or_register(&oid_udpMIB,
"The MIB module for managing UDP implementations.", module);
ipForward_reg = or_register(&oid_ipForward,
"The MIB module for the display of CIDR multipath IP Routes.",
module);
}
/*
* Initialize the module
*/
static int
mibII_init(struct lmodule *mod, int argc __unused, char *argv[] __unused)
{
size_t len;
module = mod;
len = sizeof(clockinfo);
if (sysctlbyname("kern.clockrate", &clockinfo, &len, NULL, 0) == -1) {
syslog(LOG_ERR, "kern.clockrate: %m");
return (-1);
}
if (len != sizeof(clockinfo)) {
syslog(LOG_ERR, "kern.clockrate: wrong size");
return (-1);
}
if ((route = socket(PF_ROUTE, SOCK_RAW, AF_UNSPEC)) == -1) {
syslog(LOG_ERR, "PF_ROUTE: %m");
return (-1);
}
(void)shutdown(route, SHUT_WR);
if ((mib_netsock = socket(PF_INET, SOCK_DGRAM, 0)) == -1) {
syslog(LOG_ERR, "PF_INET: %m");
(void)close(route);
return (-1);
}
(void)shutdown(mib_netsock, SHUT_RDWR);
/* assume, that all cloning interfaces are dynamic */
get_cloners();
return (0);
}
static int
mibII_fini(void)
{
if (route_fd != NULL)
fd_deselect(route_fd);
if (route != -1)
(void)close(route);
if (mib_netsock != -1)
(void)close(mib_netsock);
/* XXX free memory */
or_unregister(ipForward_reg);
or_unregister(udpmib_reg);
or_unregister(tcpmib_reg);
or_unregister(ipmib_reg);
or_unregister(ifmib_reg);
return (0);
}
static void
mibII_loading(const struct lmodule *mod, int loaded)
{
struct mibif *ifp;
if (loaded == 1)
return;
TAILQ_FOREACH(ifp, &mibif_list, link)
if (ifp->xnotify_mod == mod) {
ifp->xnotify_mod = NULL;
ifp->xnotify_data = NULL;
ifp->xnotify = NULL;
}
mib_unregister_newif(mod);
}
const struct snmp_module config = {
"This module implements the interface and ip groups.",
mibII_init,
mibII_fini,
mibII_idle, /* idle */
NULL, /* dump */
NULL, /* config */
mibII_start,
NULL,
mibII_ctree,
mibII_CTREE_SIZE,
mibII_loading
};
/*
* Should have a list of these attached to each interface.
*/
void *
mibif_notify(struct mibif *ifp, const struct lmodule *mod,
mibif_notify_f func, void *data)
{
ifp->xnotify = func;
ifp->xnotify_data = data;
ifp->xnotify_mod = mod;
return (ifp);
}
void
mibif_unnotify(void *arg)
{
struct mibif *ifp = arg;
ifp->xnotify = NULL;
ifp->xnotify_data = NULL;
ifp->xnotify_mod = NULL;
}