freebsd-dev/sbin/routed/if.c
2020-12-25 17:42:47 -08:00

1368 lines
35 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1983, 1993
* The Regents of the University of California. All rights reserved.
*
* 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.
* 3. Neither the name of the University 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 IS PROVIDED BY THE REGENTS 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 THE REGENTS 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.
*
* $FreeBSD$
*/
#include <stdint.h>
#include "defs.h"
#include "pathnames.h"
__RCSID("$FreeBSD$");
struct ifhead ifnet = LIST_HEAD_INITIALIZER(ifnet); /* all interfaces */
struct ifhead remote_if = LIST_HEAD_INITIALIZER(remote_if); /* remote interfaces */
/* hash table for all interfaces, big enough to tolerate ridiculous
* numbers of IP aliases. Crazy numbers of aliases such as 7000
* still will not do well, but not just in looking up interfaces
* by name or address.
*/
#define AHASH_LEN 211 /* must be prime */
#define AHASH(a) &ahash_tbl[(a)%AHASH_LEN]
static struct interface *ahash_tbl[AHASH_LEN];
#define BHASH_LEN 211 /* must be prime */
#define BHASH(a) &bhash_tbl[(a)%BHASH_LEN]
static struct interface *bhash_tbl[BHASH_LEN];
/* hash for physical interface names.
* Assume there are never more 100 or 200 real interfaces, and that
* aliases are put on the end of the hash chains.
*/
#define NHASH_LEN 97
static struct interface *nhash_tbl[NHASH_LEN];
int tot_interfaces; /* # of remote and local interfaces */
int rip_interfaces; /* # of interfaces doing RIP */
static int foundloopback; /* valid flag for loopaddr */
naddr loopaddr; /* our address on loopback */
static struct rt_spare loop_rts;
struct timeval ifinit_timer;
static struct timeval last_ifinit;
#define IF_RESCAN_DELAY() (last_ifinit.tv_sec == now.tv_sec \
&& last_ifinit.tv_usec == now.tv_usec \
&& timercmp(&ifinit_timer, &now, >))
int have_ripv1_out; /* have a RIPv1 interface */
static int have_ripv1_in;
static void if_bad(struct interface *);
static int addrouteforif(struct interface *);
static struct interface**
nhash(char *p)
{
u_int i;
for (i = 0; *p != '\0'; p++) {
i = ((i<<1) & 0x7fffffff) | ((i>>31) & 1);
i ^= *p;
}
return &nhash_tbl[i % NHASH_LEN];
}
/* Link a new interface into the lists and hash tables.
*/
void
if_link(struct interface *ifp)
{
struct interface **hifp;
LIST_INSERT_HEAD(&ifnet, ifp, int_list);
hifp = AHASH(ifp->int_addr);
ifp->int_ahash_prev = hifp;
if ((ifp->int_ahash = *hifp) != NULL)
(*hifp)->int_ahash_prev = &ifp->int_ahash;
*hifp = ifp;
if (ifp->int_if_flags & IFF_BROADCAST) {
hifp = BHASH(ifp->int_brdaddr);
ifp->int_bhash_prev = hifp;
if ((ifp->int_bhash = *hifp) != NULL)
(*hifp)->int_bhash_prev = &ifp->int_bhash;
*hifp = ifp;
}
if (ifp->int_state & IS_REMOTE)
LIST_INSERT_HEAD(&remote_if, ifp, remote_list);
hifp = nhash(ifp->int_name);
if (ifp->int_state & IS_ALIAS) {
/* put aliases on the end of the hash chain */
while (*hifp != NULL)
hifp = &(*hifp)->int_nhash;
}
ifp->int_nhash_prev = hifp;
if ((ifp->int_nhash = *hifp) != NULL)
(*hifp)->int_nhash_prev = &ifp->int_nhash;
*hifp = ifp;
}
/* Find the interface with an address
*/
struct interface *
ifwithaddr(naddr addr,
int bcast, /* notice IFF_BROADCAST address */
int remote) /* include IS_REMOTE interfaces */
{
struct interface *ifp, *possible = NULL;
remote = (remote == 0) ? IS_REMOTE : 0;
for (ifp = *AHASH(addr); ifp; ifp = ifp->int_ahash) {
if (ifp->int_addr != addr)
continue;
if ((ifp->int_state & remote) != 0)
continue;
if ((ifp->int_state & (IS_BROKE | IS_PASSIVE)) == 0)
return ifp;
possible = ifp;
}
if (possible || !bcast)
return possible;
for (ifp = *BHASH(addr); ifp; ifp = ifp->int_bhash) {
if (ifp->int_brdaddr != addr)
continue;
if ((ifp->int_state & remote) != 0)
continue;
if ((ifp->int_state & (IS_BROKE | IS_PASSIVE)) == 0)
return ifp;
possible = ifp;
}
return possible;
}
/* find the interface with a name
*/
static struct interface *
ifwithname(char *name, /* "ec0" or whatever */
naddr addr) /* 0 or network address */
{
struct interface *ifp;
for (;;) {
for (ifp = *nhash(name); ifp != NULL; ifp = ifp->int_nhash) {
/* If the network address is not specified,
* ignore any alias interfaces. Otherwise, look
* for the interface with the target name and address.
*/
if (!strcmp(ifp->int_name, name)
&& ((addr == 0 && !(ifp->int_state & IS_ALIAS))
|| (ifp->int_addr == addr)))
return ifp;
}
/* If there is no known interface, maybe there is a
* new interface. So just once look for new interfaces.
*/
if (IF_RESCAN_DELAY())
return 0;
ifinit();
}
}
struct interface *
ifwithindex(u_short ifindex,
int rescan_ok)
{
struct interface *ifp;
for (;;) {
LIST_FOREACH(ifp, &ifnet, int_list) {
if (ifp->int_index == ifindex)
return ifp;
}
/* If there is no known interface, maybe there is a
* new interface. So just once look for new interfaces.
*/
if (!rescan_ok
|| IF_RESCAN_DELAY())
return 0;
ifinit();
}
}
/* Find an interface from which the specified address
* should have come from. Used for figuring out which
* interface a packet came in on.
*/
struct interface *
iflookup(naddr addr)
{
struct interface *ifp, *maybe;
int once = 0;
maybe = NULL;
for (;;) {
LIST_FOREACH(ifp, &ifnet, int_list) {
if (ifp->int_if_flags & IFF_POINTOPOINT) {
/* finished with a match */
if (ifp->int_dstaddr == addr)
return ifp;
} else {
/* finished with an exact match */
if (ifp->int_addr == addr)
return ifp;
/* Look for the longest approximate match.
*/
if (on_net(addr, ifp->int_net, ifp->int_mask)
&& (maybe == NULL
|| ifp->int_mask > maybe->int_mask))
maybe = ifp;
}
}
if (maybe != NULL || once || IF_RESCAN_DELAY())
return maybe;
once = 1;
/* If there is no known interface, maybe there is a
* new interface. So just once look for new interfaces.
*/
ifinit();
}
}
/* Return the classical netmask for an IP address.
*/
naddr /* host byte order */
std_mask(naddr addr) /* network byte order */
{
addr = ntohl(addr); /* was a host, not a network */
if (addr == 0) /* default route has mask 0 */
return 0;
if (IN_CLASSA(addr))
return IN_CLASSA_NET;
if (IN_CLASSB(addr))
return IN_CLASSB_NET;
return IN_CLASSC_NET;
}
/* Find the netmask that would be inferred by RIPv1 listeners
* on the given interface for a given network.
* If no interface is specified, look for the best fitting interface.
*/
naddr
ripv1_mask_net(naddr addr, /* in network byte order */
struct interface *ifp) /* as seen on this interface */
{
struct r1net *r1p;
naddr mask = 0;
if (addr == 0) /* default always has 0 mask */
return mask;
if (ifp != NULL && ifp->int_ripv1_mask != HOST_MASK) {
/* If the target network is that of the associated interface
* on which it arrived, then use the netmask of the interface.
*/
if (on_net(addr, ifp->int_net, ifp->int_std_mask))
mask = ifp->int_ripv1_mask;
} else {
/* Examine all interfaces, and if it the target seems
* to have the same network number of an interface, use the
* netmask of that interface. If there is more than one
* such interface, prefer the interface with the longest
* match.
*/
LIST_FOREACH(ifp, &ifnet, int_list) {
if (on_net(addr, ifp->int_std_net, ifp->int_std_mask)
&& ifp->int_ripv1_mask > mask
&& ifp->int_ripv1_mask != HOST_MASK)
mask = ifp->int_ripv1_mask;
}
}
/* check special definitions */
if (mask == 0) {
for (r1p = r1nets; r1p != NULL; r1p = r1p->r1net_next) {
if (on_net(addr, r1p->r1net_net, r1p->r1net_match)
&& r1p->r1net_mask > mask)
mask = r1p->r1net_mask;
}
/* Otherwise, make the classic A/B/C guess.
*/
if (mask == 0)
mask = std_mask(addr);
}
return mask;
}
naddr
ripv1_mask_host(naddr addr, /* in network byte order */
struct interface *ifp) /* as seen on this interface */
{
naddr mask = ripv1_mask_net(addr, ifp);
/* If the computed netmask does not mask the address,
* then assume it is a host address
*/
if ((ntohl(addr) & ~mask) != 0)
mask = HOST_MASK;
return mask;
}
/* See if an IP address looks reasonable as a destination.
*/
int /* 0=bad */
check_dst(naddr addr)
{
addr = ntohl(addr);
if (IN_CLASSA(addr)) {
if (addr == 0)
return 1; /* default */
addr >>= IN_CLASSA_NSHIFT;
return (addr != 0 && addr != IN_LOOPBACKNET);
}
return (IN_CLASSB(addr) || IN_CLASSC(addr));
}
/* See a new interface duplicates an existing interface.
*/
struct interface *
check_dup(naddr addr, /* IP address, so network byte order */
naddr dstaddr, /* ditto */
naddr mask, /* mask, so host byte order */
int if_flags)
{
struct interface *ifp;
LIST_FOREACH(ifp, &ifnet, int_list) {
if (ifp->int_mask != mask)
continue;
if (!iff_up(ifp->int_if_flags))
continue;
/* The local address can only be shared with a point-to-point
* link.
*/
if ((!(ifp->int_state & IS_REMOTE) || !(if_flags & IS_REMOTE))
&& ifp->int_addr == addr
&& (((if_flags|ifp->int_if_flags) & IFF_POINTOPOINT) == 0))
return ifp;
if (on_net(ifp->int_dstaddr, ntohl(dstaddr),mask))
return ifp;
}
return 0;
}
/* See that a remote gateway is reachable.
* Note that the answer can change as real interfaces come and go.
*/
int /* 0=bad */
check_remote(struct interface *ifp)
{
struct rt_entry *rt;
/* do not worry about other kinds */
if (!(ifp->int_state & IS_REMOTE))
return 1;
rt = rtfind(ifp->int_addr);
if (rt != NULL
&& rt->rt_ifp != 0
&&on_net(ifp->int_addr,
rt->rt_ifp->int_net, rt->rt_ifp->int_mask))
return 1;
/* the gateway cannot be reached directly from one of our
* interfaces
*/
if (!(ifp->int_state & IS_BROKE)) {
msglog("unreachable gateway %s in "_PATH_GATEWAYS,
naddr_ntoa(ifp->int_addr));
if_bad(ifp);
}
return 0;
}
/* Delete an interface.
*/
static void
ifdel(struct interface *ifp)
{
struct interface *ifp1;
trace_if("Del", ifp);
ifp->int_state |= IS_BROKE;
LIST_REMOVE(ifp, int_list);
*ifp->int_ahash_prev = ifp->int_ahash;
if (ifp->int_ahash != 0)
ifp->int_ahash->int_ahash_prev = ifp->int_ahash_prev;
*ifp->int_nhash_prev = ifp->int_nhash;
if (ifp->int_nhash != 0)
ifp->int_nhash->int_nhash_prev = ifp->int_nhash_prev;
if (ifp->int_if_flags & IFF_BROADCAST) {
*ifp->int_bhash_prev = ifp->int_bhash;
if (ifp->int_bhash != 0)
ifp->int_bhash->int_bhash_prev = ifp->int_bhash_prev;
}
if (ifp->int_state & IS_REMOTE)
LIST_REMOVE(ifp, remote_list);
if (!(ifp->int_state & IS_ALIAS)) {
/* delete aliases when the main interface dies
*/
LIST_FOREACH(ifp1, &ifnet, int_list) {
if (ifp1 != ifp
&& !strcmp(ifp->int_name, ifp1->int_name))
ifdel(ifp1);
}
if ((ifp->int_if_flags & IFF_MULTICAST) && rip_sock >= 0) {
struct group_req gr;
struct sockaddr_in *sin;
memset(&gr, 0, sizeof(gr));
gr.gr_interface = ifp->int_index;
sin = (struct sockaddr_in *)&gr.gr_group;
sin->sin_family = AF_INET;
#ifdef _HAVE_SIN_LEN
sin->sin_len = sizeof(struct sockaddr_in);
#endif
sin->sin_addr.s_addr = htonl(INADDR_RIP_GROUP);
if (setsockopt(rip_sock, IPPROTO_IP, MCAST_LEAVE_GROUP,
&gr, sizeof(gr)) < 0
&& errno != EADDRNOTAVAIL
&& !TRACEACTIONS)
LOGERR("setsockopt(MCAST_LEAVE_GROUP RIP)");
if (rip_sock_mcast == ifp)
rip_sock_mcast = NULL;
}
if (ifp->int_rip_sock >= 0) {
(void)close(ifp->int_rip_sock);
ifp->int_rip_sock = -1;
fix_select();
}
tot_interfaces--;
if (!IS_RIP_OFF(ifp->int_state))
rip_interfaces--;
/* Zap all routes associated with this interface.
* Assume routes just using gateways beyond this interface
* will timeout naturally, and have probably already died.
*/
(void)rn_walktree(rhead, walk_bad, 0);
set_rdisc_mg(ifp, 0);
if_bad_rdisc(ifp);
}
free(ifp);
}
/* Mark an interface ill.
*/
void
if_sick(struct interface *ifp)
{
if (0 == (ifp->int_state & (IS_SICK | IS_BROKE))) {
ifp->int_state |= IS_SICK;
ifp->int_act_time = NEVER;
trace_if("Chg", ifp);
LIM_SEC(ifinit_timer, now.tv_sec+CHECK_BAD_INTERVAL);
}
}
/* Mark an interface dead.
*/
static void
if_bad(struct interface *ifp)
{
struct interface *ifp1;
if (ifp->int_state & IS_BROKE)
return;
LIM_SEC(ifinit_timer, now.tv_sec+CHECK_BAD_INTERVAL);
ifp->int_state |= (IS_BROKE | IS_SICK);
ifp->int_act_time = NEVER;
ifp->int_query_time = NEVER;
ifp->int_data.ts = now.tv_sec;
trace_if("Chg", ifp);
if (!(ifp->int_state & IS_ALIAS)) {
LIST_FOREACH(ifp1, &ifnet, int_list) {
if (ifp1 != ifp
&& !strcmp(ifp->int_name, ifp1->int_name))
if_bad(ifp1);
}
(void)rn_walktree(rhead, walk_bad, 0);
if_bad_rdisc(ifp);
}
}
/* Mark an interface alive
*/
int /* 1=it was dead */
if_ok(struct interface *ifp,
const char *type)
{
struct interface *ifp1;
if (!(ifp->int_state & IS_BROKE)) {
if (ifp->int_state & IS_SICK) {
trace_act("%sinterface %s to %s working better",
type,
ifp->int_name, naddr_ntoa(ifp->int_dstaddr));
ifp->int_state &= ~IS_SICK;
}
return 0;
}
msglog("%sinterface %s to %s restored",
type, ifp->int_name, naddr_ntoa(ifp->int_dstaddr));
ifp->int_state &= ~(IS_BROKE | IS_SICK);
ifp->int_data.ts = 0;
if (!(ifp->int_state & IS_ALIAS)) {
LIST_FOREACH(ifp1, &ifnet, int_list) {
if (ifp1 != ifp
&& !strcmp(ifp->int_name, ifp1->int_name))
if_ok(ifp1, type);
}
if_ok_rdisc(ifp);
}
if (ifp->int_state & IS_REMOTE) {
if (!addrouteforif(ifp))
return 0;
}
return 1;
}
/* disassemble routing message
*/
void
rt_xaddrs(struct rt_addrinfo *info,
struct sockaddr *sa,
struct sockaddr *lim,
int addrs)
{
int i;
#ifdef _HAVE_SA_LEN
static struct sockaddr sa_zero;
#endif
memset(info, 0, sizeof(*info));
info->rti_addrs = addrs;
for (i = 0; i < RTAX_MAX && sa < lim; i++) {
if ((addrs & (1 << i)) == 0)
continue;
info->rti_info[i] = (sa->sa_len != 0) ? sa : &sa_zero;
sa = (struct sockaddr *)((char*)(sa) + SA_SIZE(sa));
}
}
/* Find the network interfaces which have configured themselves.
* This must be done regularly, if only for extra addresses
* that come and go on interfaces.
*/
void
ifinit(void)
{
static struct ifa_msghdr *sysctl_buf;
static size_t sysctl_buf_size = 0;
uint complaints = 0;
static u_int prev_complaints = 0;
# define COMP_NOT_INET 0x001
# define COMP_NOADDR 0x002
# define COMP_BADADDR 0x004
# define COMP_NODST 0x008
# define COMP_NOBADR 0x010
# define COMP_NOMASK 0x020
# define COMP_DUP 0x040
# define COMP_BAD_METRIC 0x080
# define COMP_NETMASK 0x100
struct interface ifs, ifs0, *ifp, *ifp1;
struct rt_entry *rt;
size_t needed;
int mib[6];
struct if_msghdr *ifm;
void *ifam_lim;
struct ifa_msghdr *ifam, *ifam2;
int in, ierr, out, oerr;
struct intnet *intnetp;
struct rt_addrinfo info;
#ifdef SIOCGIFMETRIC
struct ifreq ifr;
#endif
last_ifinit = now;
ifinit_timer.tv_sec = now.tv_sec + (supplier
? CHECK_ACT_INTERVAL
: CHECK_QUIET_INTERVAL);
/* mark all interfaces so we can get rid of those that disappear */
LIST_FOREACH(ifp, &ifnet, int_list)
ifp->int_state &= ~(IS_CHECKED | IS_DUP);
/* Fetch the interface list, without too many system calls
* since we do it repeatedly.
*/
mib[0] = CTL_NET;
mib[1] = PF_ROUTE;
mib[2] = 0;
mib[3] = AF_INET;
mib[4] = NET_RT_IFLIST;
mib[5] = 0;
for (;;) {
if ((needed = sysctl_buf_size) != 0) {
if (sysctl(mib, 6, sysctl_buf,&needed, 0, 0) >= 0)
break;
/* retry if the table grew */
if (errno != ENOMEM && errno != EFAULT)
BADERR(1, "ifinit: sysctl(RT_IFLIST)");
free(sysctl_buf);
needed = 0;
}
if (sysctl(mib, 6, 0, &needed, 0, 0) < 0)
BADERR(1,"ifinit: sysctl(RT_IFLIST) estimate");
sysctl_buf = rtmalloc(sysctl_buf_size = needed,
"ifinit sysctl");
}
/* XXX: thanks to malloc(3), alignment can be presumed OK */
ifam_lim = (char *)sysctl_buf + needed;
for (ifam = sysctl_buf; (void *)ifam < ifam_lim; ifam = ifam2) {
ifam2 = (struct ifa_msghdr*)((char*)ifam + ifam->ifam_msglen);
#ifdef RTM_OIFINFO
if (ifam->ifam_type == RTM_OIFINFO)
continue; /* just ignore compat message */
#endif
if (ifam->ifam_type == RTM_IFINFO) {
struct sockaddr_dl *sdl;
ifm = (struct if_msghdr *)ifam;
/* make prototype structure for the IP aliases
*/
memset(&ifs0, 0, sizeof(ifs0));
ifs0.int_rip_sock = -1;
ifs0.int_index = ifm->ifm_index;
ifs0.int_if_flags = ifm->ifm_flags;
ifs0.int_state = IS_CHECKED;
ifs0.int_query_time = NEVER;
ifs0.int_act_time = now.tv_sec;
ifs0.int_data.ts = now.tv_sec;
ifs0.int_data.ipackets = ifm->ifm_data.ifi_ipackets;
ifs0.int_data.ierrors = ifm->ifm_data.ifi_ierrors;
ifs0.int_data.opackets = ifm->ifm_data.ifi_opackets;
ifs0.int_data.oerrors = ifm->ifm_data.ifi_oerrors;
sdl = (struct sockaddr_dl *)(ifm + 1);
sdl->sdl_data[sdl->sdl_nlen] = 0;
strncpy(ifs0.int_name, sdl->sdl_data,
MIN(sizeof(ifs0.int_name), sdl->sdl_nlen));
continue;
}
if (ifam->ifam_type != RTM_NEWADDR) {
logbad(1,"ifinit: out of sync");
continue;
}
rt_xaddrs(&info, (struct sockaddr *)(ifam+1),
(struct sockaddr *)ifam2,
ifam->ifam_addrs);
/* Prepare for the next address of this interface, which
* will be an alias.
* Do not output RIP or Router-Discovery packets via aliases.
*/
memcpy(&ifs, &ifs0, sizeof(ifs));
ifs0.int_state |= (IS_ALIAS | IS_NO_RIP_OUT | IS_NO_RDISC);
if (INFO_IFA(&info) == 0) {
if (iff_up(ifs.int_if_flags)) {
if (!(prev_complaints & COMP_NOADDR))
msglog("%s has no address",
ifs.int_name);
complaints |= COMP_NOADDR;
}
continue;
}
if (INFO_IFA(&info)->sa_family != AF_INET) {
if (iff_up(ifs.int_if_flags)) {
if (!(prev_complaints & COMP_NOT_INET))
trace_act("%s: not AF_INET",
ifs.int_name);
complaints |= COMP_NOT_INET;
}
continue;
}
ifs.int_addr = S_ADDR(INFO_IFA(&info));
if (ntohl(ifs.int_addr)>>24 == 0
|| ntohl(ifs.int_addr)>>24 == 0xff) {
if (iff_up(ifs.int_if_flags)) {
if (!(prev_complaints & COMP_BADADDR))
msglog("%s has a bad address",
ifs.int_name);
complaints |= COMP_BADADDR;
}
continue;
}
if (ifs.int_if_flags & IFF_LOOPBACK) {
ifs.int_state |= IS_NO_RIP | IS_NO_RDISC;
if (ifs.int_addr == htonl(INADDR_LOOPBACK))
ifs.int_state |= IS_PASSIVE;
ifs.int_dstaddr = ifs.int_addr;
ifs.int_mask = HOST_MASK;
ifs.int_ripv1_mask = HOST_MASK;
ifs.int_std_mask = std_mask(ifs.int_dstaddr);
ifs.int_net = ntohl(ifs.int_dstaddr);
if (!foundloopback) {
foundloopback = 1;
loopaddr = ifs.int_addr;
loop_rts.rts_gate = loopaddr;
loop_rts.rts_router = loopaddr;
}
} else if (ifs.int_if_flags & IFF_POINTOPOINT) {
if (INFO_BRD(&info) == 0
|| INFO_BRD(&info)->sa_family != AF_INET) {
if (iff_up(ifs.int_if_flags)) {
if (!(prev_complaints & COMP_NODST))
msglog("%s has a bad"
" destination address",
ifs.int_name);
complaints |= COMP_NODST;
}
continue;
}
ifs.int_dstaddr = S_ADDR(INFO_BRD(&info));
if (ntohl(ifs.int_dstaddr)>>24 == 0
|| ntohl(ifs.int_dstaddr)>>24 == 0xff) {
if (iff_up(ifs.int_if_flags)) {
if (!(prev_complaints & COMP_NODST))
msglog("%s has a bad"
" destination address",
ifs.int_name);
complaints |= COMP_NODST;
}
continue;
}
ifs.int_mask = HOST_MASK;
ifs.int_ripv1_mask = ntohl(S_ADDR(INFO_MASK(&info)));
ifs.int_std_mask = std_mask(ifs.int_dstaddr);
ifs.int_net = ntohl(ifs.int_dstaddr);
} else {
if (INFO_MASK(&info) == 0) {
if (iff_up(ifs.int_if_flags)) {
if (!(prev_complaints & COMP_NOMASK))
msglog("%s has no netmask",
ifs.int_name);
complaints |= COMP_NOMASK;
}
continue;
}
ifs.int_dstaddr = ifs.int_addr;
ifs.int_mask = ntohl(S_ADDR(INFO_MASK(&info)));
ifs.int_ripv1_mask = ifs.int_mask;
ifs.int_std_mask = std_mask(ifs.int_addr);
ifs.int_net = ntohl(ifs.int_addr) & ifs.int_mask;
if (ifs.int_mask != ifs.int_std_mask)
ifs.int_state |= IS_SUBNET;
if (ifs.int_if_flags & IFF_BROADCAST) {
if (INFO_BRD(&info) == 0) {
if (iff_up(ifs.int_if_flags)) {
if (!(prev_complaints
& COMP_NOBADR))
msglog("%s has"
"no broadcast address",
ifs.int_name);
complaints |= COMP_NOBADR;
}
continue;
}
ifs.int_brdaddr = S_ADDR(INFO_BRD(&info));
}
}
ifs.int_std_net = ifs.int_net & ifs.int_std_mask;
ifs.int_std_addr = htonl(ifs.int_std_net);
/* Use a minimum metric of one. Treat the interface metric
* (default 0) as an increment to the hop count of one.
*
* The metric obtained from the routing socket dump of
* interface addresses is wrong. It is not set by the
* SIOCSIFMETRIC ioctl.
*/
#ifdef SIOCGIFMETRIC
strncpy(ifr.ifr_name, ifs.int_name, sizeof(ifr.ifr_name));
if (ioctl(rt_sock, SIOCGIFMETRIC, &ifr) < 0) {
DBGERR(1, "ioctl(SIOCGIFMETRIC)");
ifs.int_metric = 0;
} else {
ifs.int_metric = ifr.ifr_metric;
}
#else
ifs.int_metric = ifam->ifam_metric;
#endif
if (ifs.int_metric > HOPCNT_INFINITY) {
ifs.int_metric = 0;
if (!(prev_complaints & COMP_BAD_METRIC)
&& iff_up(ifs.int_if_flags)) {
complaints |= COMP_BAD_METRIC;
msglog("%s has a metric of %d",
ifs.int_name, ifs.int_metric);
}
}
/* See if this is a familiar interface.
* If so, stop worrying about it if it is the same.
* Start it over if it now is to somewhere else, as happens
* frequently with PPP and SLIP.
*/
ifp = ifwithname(ifs.int_name, ((ifs.int_state & IS_ALIAS)
? ifs.int_addr
: 0));
if (ifp != NULL) {
ifp->int_state |= IS_CHECKED;
if (0 != ((ifp->int_if_flags ^ ifs.int_if_flags)
& (IFF_BROADCAST
| IFF_LOOPBACK
| IFF_POINTOPOINT
| IFF_MULTICAST))
|| 0 != ((ifp->int_state ^ ifs.int_state)
& IS_ALIAS)
|| ifp->int_addr != ifs.int_addr
|| ifp->int_brdaddr != ifs.int_brdaddr
|| ifp->int_dstaddr != ifs.int_dstaddr
|| ifp->int_mask != ifs.int_mask
|| ifp->int_metric != ifs.int_metric) {
/* Forget old information about
* a changed interface.
*/
trace_act("interface %s has changed",
ifp->int_name);
ifdel(ifp);
ifp = NULL;
}
}
if (ifp != NULL) {
/* The primary representative of an alias worries
* about how things are working.
*/
if (ifp->int_state & IS_ALIAS)
continue;
/* note interfaces that have been turned off
*/
if (!iff_up(ifs.int_if_flags)) {
if (iff_up(ifp->int_if_flags)) {
msglog("interface %s to %s turned off",
ifp->int_name,
naddr_ntoa(ifp->int_dstaddr));
if_bad(ifp);
ifp->int_if_flags &= ~IFF_UP;
} else if (now.tv_sec>(ifp->int_data.ts
+ CHECK_BAD_INTERVAL)) {
trace_act("interface %s has been off"
" %jd seconds; forget it",
ifp->int_name,
(intmax_t)now.tv_sec -
ifp->int_data.ts);
ifdel(ifp);
ifp = NULL;
}
continue;
}
/* or that were off and are now ok */
if (!iff_up(ifp->int_if_flags)) {
ifp->int_if_flags |= IFF_UP;
(void)if_ok(ifp, "");
}
/* If it has been long enough,
* see if the interface is broken.
*/
if (now.tv_sec < ifp->int_data.ts+CHECK_BAD_INTERVAL)
continue;
in = ifs.int_data.ipackets - ifp->int_data.ipackets;
ierr = ifs.int_data.ierrors - ifp->int_data.ierrors;
out = ifs.int_data.opackets - ifp->int_data.opackets;
oerr = ifs.int_data.oerrors - ifp->int_data.oerrors;
/* If the interface just awoke, restart the counters.
*/
if (ifp->int_data.ts == 0) {
ifp->int_data = ifs.int_data;
continue;
}
ifp->int_data = ifs.int_data;
/* Withhold judgment when the short error
* counters wrap or the interface is reset.
*/
if (ierr < 0 || in < 0 || oerr < 0 || out < 0) {
LIM_SEC(ifinit_timer,
now.tv_sec+CHECK_BAD_INTERVAL);
continue;
}
/* Withhold judgement when there is no traffic
*/
if (in == 0 && out == 0 && ierr == 0 && oerr == 0)
continue;
/* It is bad if input or output is not working.
* Require presistent problems before marking it dead.
*/
if ((in <= ierr && ierr > 0)
|| (out <= oerr && oerr > 0)) {
if (!(ifp->int_state & IS_SICK)) {
trace_act("interface %s to %s"
" sick: in=%d ierr=%d"
" out=%d oerr=%d",
ifp->int_name,
naddr_ntoa(ifp->int_dstaddr),
in, ierr, out, oerr);
if_sick(ifp);
continue;
}
if (!(ifp->int_state & IS_BROKE)) {
msglog("interface %s to %s broken:"
" in=%d ierr=%d out=%d oerr=%d",
ifp->int_name,
naddr_ntoa(ifp->int_dstaddr),
in, ierr, out, oerr);
if_bad(ifp);
}
continue;
}
/* otherwise, it is active and healthy
*/
ifp->int_act_time = now.tv_sec;
(void)if_ok(ifp, "");
continue;
}
/* This is a new interface.
* If it is dead, forget it.
*/
if (!iff_up(ifs.int_if_flags))
continue;
/* If it duplicates an existing interface,
* complain about it, mark the other one
* duplicated, and forget this one.
*/
ifp = check_dup(ifs.int_addr,ifs.int_dstaddr,ifs.int_mask,
ifs.int_if_flags);
if (ifp != NULL) {
/* Ignore duplicates of itself, caused by having
* IP aliases on the same network.
*/
if (!strcmp(ifp->int_name, ifs.int_name))
continue;
if (!(prev_complaints & COMP_DUP)) {
complaints |= COMP_DUP;
msglog("%s (%s%s%s) is duplicated by"
" %s (%s%s%s)",
ifs.int_name,
addrname(ifs.int_addr,ifs.int_mask,1),
((ifs.int_if_flags & IFF_POINTOPOINT)
? "-->" : ""),
((ifs.int_if_flags & IFF_POINTOPOINT)
? naddr_ntoa(ifs.int_dstaddr) : ""),
ifp->int_name,
addrname(ifp->int_addr,ifp->int_mask,1),
((ifp->int_if_flags & IFF_POINTOPOINT)
? "-->" : ""),
((ifp->int_if_flags & IFF_POINTOPOINT)
? naddr_ntoa(ifp->int_dstaddr) : ""));
}
ifp->int_state |= IS_DUP;
continue;
}
if (0 == (ifs.int_if_flags & (IFF_POINTOPOINT | IFF_BROADCAST | IFF_LOOPBACK))) {
trace_act("%s is neither broadcast, point-to-point,"
" nor loopback",
ifs.int_name);
if (!(ifs.int_state & IFF_MULTICAST))
ifs.int_state |= IS_NO_RDISC;
}
/* It is new and ok. Add it to the list of interfaces
*/
ifp = (struct interface *)rtmalloc(sizeof(*ifp), "ifinit ifp");
memcpy(ifp, &ifs, sizeof(*ifp));
get_parms(ifp);
if_link(ifp);
trace_if("Add", ifp);
/* Notice likely bad netmask.
*/
if (!(prev_complaints & COMP_NETMASK)
&& !(ifp->int_if_flags & IFF_POINTOPOINT)
&& ifp->int_addr != RIP_DEFAULT) {
LIST_FOREACH(ifp1, &ifnet, int_list) {
if (ifp1->int_mask == ifp->int_mask)
continue;
if (ifp1->int_if_flags & IFF_POINTOPOINT)
continue;
if (ifp1->int_dstaddr == RIP_DEFAULT)
continue;
/* ignore aliases on the right network */
if (!strcmp(ifp->int_name, ifp1->int_name))
continue;
if (on_net(ifp->int_dstaddr,
ifp1->int_net, ifp1->int_mask)
|| on_net(ifp1->int_dstaddr,
ifp->int_net, ifp->int_mask)) {
msglog("possible netmask problem"
" between %s:%s and %s:%s",
ifp->int_name,
addrname(htonl(ifp->int_net),
ifp->int_mask, 1),
ifp1->int_name,
addrname(htonl(ifp1->int_net),
ifp1->int_mask, 1));
complaints |= COMP_NETMASK;
}
}
}
if (!(ifp->int_state & IS_ALIAS)) {
/* Count the # of directly connected networks.
*/
if (!(ifp->int_if_flags & IFF_LOOPBACK))
tot_interfaces++;
if (!IS_RIP_OFF(ifp->int_state))
rip_interfaces++;
/* turn on router discovery and RIP If needed */
if_ok_rdisc(ifp);
rip_on(ifp);
}
}
/* If we are multi-homed and have at least two interfaces
* listening to RIP, then output by default.
*/
if (!supplier_set && rip_interfaces > 1)
set_supplier();
/* If we are multi-homed, optionally advertise a route to
* our main address.
*/
if ((advertise_mhome && ifp)
|| (tot_interfaces > 1
&& mhome
&& (ifp = ifwithaddr(myaddr, 0, 0)) != NULL
&& foundloopback)) {
advertise_mhome = 1;
rt = rtget(myaddr, HOST_MASK);
if (rt != NULL) {
if (rt->rt_ifp != ifp
|| rt->rt_router != loopaddr) {
rtdelete(rt);
rt = NULL;
} else {
loop_rts.rts_ifp = ifp;
loop_rts.rts_metric = 0;
loop_rts.rts_time = rt->rt_time;
rtchange(rt, rt->rt_state | RS_MHOME,
&loop_rts, 0);
}
}
if (rt == NULL) {
loop_rts.rts_ifp = ifp;
loop_rts.rts_metric = 0;
rtadd(myaddr, HOST_MASK, RS_MHOME, &loop_rts);
}
}
LIST_FOREACH_SAFE(ifp, &ifnet, int_list, ifp1) {
/* Forget any interfaces that have disappeared.
*/
if (!(ifp->int_state & (IS_CHECKED | IS_REMOTE))) {
trace_act("interface %s has disappeared",
ifp->int_name);
ifdel(ifp);
continue;
}
if ((ifp->int_state & IS_BROKE)
&& !(ifp->int_state & IS_PASSIVE))
LIM_SEC(ifinit_timer, now.tv_sec+CHECK_BAD_INTERVAL);
/* If we ever have a RIPv1 interface, assume we always will.
* It might come back if it ever goes away.
*/
if (!(ifp->int_state & IS_NO_RIPV1_OUT) && supplier)
have_ripv1_out = 1;
if (!(ifp->int_state & IS_NO_RIPV1_IN))
have_ripv1_in = 1;
}
LIST_FOREACH(ifp, &ifnet, int_list) {
/* Ensure there is always a network route for interfaces,
* after any dead interfaces have been deleted, which
* might affect routes for point-to-point links.
*/
if (!addrouteforif(ifp))
continue;
/* Add routes to the local end of point-to-point interfaces
* using loopback.
*/
if ((ifp->int_if_flags & IFF_POINTOPOINT)
&& !(ifp->int_state & IS_REMOTE)
&& foundloopback) {
/* Delete any routes to the network address through
* foreign routers. Remove even static routes.
*/
del_static(ifp->int_addr, HOST_MASK, 0, 0);
rt = rtget(ifp->int_addr, HOST_MASK);
if (rt != NULL && rt->rt_router != loopaddr) {
rtdelete(rt);
rt = NULL;
}
if (rt != NULL) {
if (!(rt->rt_state & RS_LOCAL)
|| rt->rt_metric > ifp->int_metric) {
ifp1 = ifp;
} else {
ifp1 = rt->rt_ifp;
}
loop_rts.rts_ifp = ifp1;
loop_rts.rts_metric = 0;
loop_rts.rts_time = rt->rt_time;
rtchange(rt, ((rt->rt_state & ~RS_NET_SYN)
| (RS_IF|RS_LOCAL)),
&loop_rts, 0);
} else {
loop_rts.rts_ifp = ifp;
loop_rts.rts_metric = 0;
rtadd(ifp->int_addr, HOST_MASK,
(RS_IF | RS_LOCAL), &loop_rts);
}
}
}
/* add the authority routes */
for (intnetp = intnets; intnetp != NULL;
intnetp = intnetp->intnet_next) {
rt = rtget(intnetp->intnet_addr, intnetp->intnet_mask);
if (rt != NULL
&& !(rt->rt_state & RS_NO_NET_SYN)
&& !(rt->rt_state & RS_NET_INT)) {
rtdelete(rt);
rt = NULL;
}
if (rt == NULL) {
loop_rts.rts_ifp = NULL;
loop_rts.rts_metric = intnetp->intnet_metric-1;
rtadd(intnetp->intnet_addr, intnetp->intnet_mask,
RS_NET_SYN | RS_NET_INT, &loop_rts);
}
}
prev_complaints = complaints;
}
static void
check_net_syn(struct interface *ifp)
{
struct rt_entry *rt;
static struct rt_spare new;
/* Turn on the need to automatically synthesize a network route
* for this interface only if we are running RIPv1 on some other
* interface that is on a different class-A,B,or C network.
*/
if (have_ripv1_out || have_ripv1_in) {
ifp->int_state |= IS_NEED_NET_SYN;
rt = rtget(ifp->int_std_addr, ifp->int_std_mask);
if (rt != NULL
&& 0 == (rt->rt_state & RS_NO_NET_SYN)
&& (!(rt->rt_state & RS_NET_SYN)
|| rt->rt_metric > ifp->int_metric)) {
rtdelete(rt);
rt = NULL;
}
if (rt == NULL) {
new.rts_ifp = ifp;
new.rts_gate = ifp->int_addr;
new.rts_router = ifp->int_addr;
new.rts_metric = ifp->int_metric;
rtadd(ifp->int_std_addr, ifp->int_std_mask,
RS_NET_SYN, &new);
}
} else {
ifp->int_state &= ~IS_NEED_NET_SYN;
rt = rtget(ifp->int_std_addr,
ifp->int_std_mask);
if (rt != NULL
&& (rt->rt_state & RS_NET_SYN)
&& rt->rt_ifp == ifp)
rtbad_sub(rt);
}
}
/* Add route for interface if not currently installed.
* Create route to other end if a point-to-point link,
* otherwise a route to this (sub)network.
*/
static int /* 0=bad interface */
addrouteforif(struct interface *ifp)
{
struct rt_entry *rt;
static struct rt_spare new;
naddr dst;
/* skip sick interfaces
*/
if (ifp->int_state & IS_BROKE)
return 0;
/* If the interface on a subnet, then install a RIPv1 route to
* the network as well (unless it is sick).
*/
if (ifp->int_state & IS_SUBNET)
check_net_syn(ifp);
dst = (0 != (ifp->int_if_flags & (IFF_POINTOPOINT | IFF_LOOPBACK))
? ifp->int_dstaddr
: htonl(ifp->int_net));
new.rts_ifp = ifp;
new.rts_router = ifp->int_addr;
new.rts_gate = ifp->int_addr;
new.rts_metric = ifp->int_metric;
new.rts_time = now.tv_sec;
/* If we are going to send packets to the gateway,
* it must be reachable using our physical interfaces
*/
if ((ifp->int_state & IS_REMOTE)
&& !(ifp->int_state & IS_EXTERNAL)
&& !check_remote(ifp))
return 0;
/* We are finished if the correct main interface route exists.
* The right route must be for the right interface, not synthesized
* from a subnet, be a "gateway" or not as appropriate, and so forth.
*/
del_static(dst, ifp->int_mask, 0, 0);
rt = rtget(dst, ifp->int_mask);
if (rt != NULL) {
if ((rt->rt_ifp != ifp
|| rt->rt_router != ifp->int_addr)
&& (!(ifp->int_state & IS_DUP)
|| rt->rt_ifp == 0
|| (rt->rt_ifp->int_state & IS_BROKE))) {
rtdelete(rt);
rt = NULL;
} else {
rtchange(rt, ((rt->rt_state | RS_IF)
& ~(RS_NET_SYN | RS_LOCAL)),
&new, 0);
}
}
if (rt == NULL) {
if (ifp->int_transitions++ > 0)
trace_act("re-install interface %s",
ifp->int_name);
rtadd(dst, ifp->int_mask, RS_IF, &new);
}
return 1;
}