FreeBSD-5.3/libexec/bootpd/rtmsg.c
/*
* Copyright (c) 1984, 1993
* The Regents of the University of California. All rights reserved.
* Copyright (c) 1994
* Geoffrey M. Rehmet, All rights reserved.
*
* This code is derived from software which forms part of the 4.4-Lite
* Berkeley software distribution, which was in derived from software
* contributed to Berkeley by Sun Microsystems, Inc.
*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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.
*/
/*
* from arp.c 8.2 (Berkeley) 1/2/94
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD: src/libexec/bootpd/rtmsg.c,v 1.12 2003/02/05 13:45:25 charnier Exp $");
#include <sys/param.h>
/*
* Verify that we are at least 4.4 BSD
*/
#if defined(BSD)
#if BSD >= 199306
#include <sys/socket.h>
#include <sys/filio.h>
#include <sys/time.h>
#include <net/if.h>
#include <net/if_dl.h>
#include <net/if_types.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/if_ether.h>
#include <arpa/inet.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <unistd.h>
#include "report.h"
static int rtmsg(int);
static int s = -1; /* routing socket */
/*
* Open the routing socket
*/
static void getsocket () {
if (s < 0) {
s = socket(PF_ROUTE, SOCK_RAW, 0);
if (s < 0) {
report(LOG_ERR, "socket %s", strerror(errno));
exit(1);
}
} else {
/*
* Drain the socket of any unwanted routing messages.
*/
int n;
char buf[512];
ioctl(s, FIONREAD, &n);
while (n > 0) {
read(s, buf, sizeof buf);
ioctl(s, FIONREAD, &n);
}
}
}
static struct sockaddr_in so_mask = {8, 0, 0, { 0xffffffff}};
static struct sockaddr_inarp blank_sin = {sizeof(blank_sin), AF_INET }, sin_m;
static struct sockaddr_dl blank_sdl = {sizeof(blank_sdl), AF_LINK }, sdl_m;
static int expire_time, flags, export_only, doing_proxy;
static struct {
struct rt_msghdr m_rtm;
char m_space[512];
} m_rtmsg;
/*
* Set an individual arp entry
*/
int bsd_arp_set(ia, eaddr, len)
struct in_addr *ia;
char *eaddr;
int len;
{
register struct sockaddr_inarp *sin = &sin_m;
register struct sockaddr_dl *sdl;
register struct rt_msghdr *rtm = &(m_rtmsg.m_rtm);
u_char *ea;
struct timeval time;
int op = RTM_ADD;
getsocket();
sdl_m = blank_sdl;
sin_m = blank_sin;
sin->sin_addr = *ia;
ea = (u_char *)LLADDR(&sdl_m);
bcopy(eaddr, ea, len);
sdl_m.sdl_alen = len;
doing_proxy = flags = export_only = expire_time = 0;
/* make arp entry temporary */
gettimeofday(&time, 0);
expire_time = time.tv_sec + 20 * 60;
tryagain:
if (rtmsg(RTM_GET) < 0) {
report(LOG_WARNING, "rtmget: %s", strerror(errno));
return (1);
}
sin = (struct sockaddr_inarp *)(rtm + 1);
sdl = (struct sockaddr_dl *)(sin->sin_len + (char *)sin);
if (sin->sin_addr.s_addr == sin_m.sin_addr.s_addr) {
if (sdl->sdl_family == AF_LINK &&
(rtm->rtm_flags & RTF_LLINFO) &&
!(rtm->rtm_flags & RTF_GATEWAY)) switch (sdl->sdl_type) {
case IFT_ETHER: case IFT_FDDI: case IFT_ISO88023:
case IFT_ISO88024: case IFT_ISO88025:
op = RTM_CHANGE;
goto overwrite;
}
if (doing_proxy == 0) {
report(LOG_WARNING, "set: can only proxy for %s\n",
inet_ntoa(sin->sin_addr));
return (1);
}
if (sin_m.sin_other & SIN_PROXY) {
report(LOG_WARNING,
"set: proxy entry exists for non 802 device\n");
return(1);
}
sin_m.sin_other = SIN_PROXY;
export_only = 1;
goto tryagain;
}
overwrite:
if (sdl->sdl_family != AF_LINK) {
report(LOG_WARNING,
"cannot intuit interface index and type for %s\n",
inet_ntoa(sin->sin_addr));
return (1);
}
sdl_m.sdl_type = sdl->sdl_type;
sdl_m.sdl_index = sdl->sdl_index;
return (rtmsg(op));
}
static int rtmsg(cmd)
int cmd;
{
static int seq;
int rlen;
register struct rt_msghdr *rtm = &m_rtmsg.m_rtm;
register char *cp = m_rtmsg.m_space;
register int l;
errno = 0;
bzero((char *)&m_rtmsg, sizeof(m_rtmsg));
rtm->rtm_flags = flags;
rtm->rtm_version = RTM_VERSION;
switch (cmd) {
default:
report(LOG_ERR, "set_arp: internal wrong cmd - exiting");
exit(1);
case RTM_ADD:
case RTM_CHANGE:
rtm->rtm_addrs |= RTA_GATEWAY;
rtm->rtm_rmx.rmx_expire = expire_time;
rtm->rtm_inits = RTV_EXPIRE;
rtm->rtm_flags |= (RTF_HOST | RTF_STATIC);
sin_m.sin_other = 0;
if (doing_proxy) {
if (export_only)
sin_m.sin_other = SIN_PROXY;
else {
rtm->rtm_addrs |= RTA_NETMASK;
rtm->rtm_flags &= ~RTF_HOST;
}
}
/* FALLTHROUGH */
case RTM_GET:
rtm->rtm_addrs |= RTA_DST;
}
#define NEXTADDR(w, s) \
if (rtm->rtm_addrs & (w)) { \
bcopy((char *)&s, cp, sizeof(s)); cp += sizeof(s);}
NEXTADDR(RTA_DST, sin_m);
NEXTADDR(RTA_GATEWAY, sdl_m);
NEXTADDR(RTA_NETMASK, so_mask);
rtm->rtm_msglen = cp - (char *)&m_rtmsg;
l = rtm->rtm_msglen;
rtm->rtm_seq = ++seq;
rtm->rtm_type = cmd;
if ((rlen = write(s, (char *)&m_rtmsg, l)) < 0) {
if ((errno != ESRCH) && !(errno == EEXIST && cmd == RTM_ADD)){
report(LOG_WARNING, "writing to routing socket: %s",
strerror(errno));
return (-1);
}
}
do {
l = read(s, (char *)&m_rtmsg, sizeof(m_rtmsg));
} while (l > 0 && (rtm->rtm_type != cmd || rtm->rtm_seq != seq || rtm->rtm_pid != getpid()));
if (l < 0)
report(LOG_WARNING, "arp: read from routing socket: %s\n",
strerror(errno));
return (0);
}
#endif /* BSD */
#endif /* BSD >= 199306 */