545 lines
13 KiB
C
545 lines
13 KiB
C
/* $NetBSD: arp.c,v 1.12 1995/04/24 13:25:18 cgd Exp $ */
|
|
|
|
/*
|
|
* Copyright (c) 1984, 1993
|
|
* The Regents of the University of California. All rights reserved.
|
|
*
|
|
* This code is 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.
|
|
*/
|
|
|
|
#ifndef lint
|
|
static char copyright[] =
|
|
"@(#) Copyright (c) 1984, 1993\n\
|
|
The Regents of the University of California. All rights reserved.\n";
|
|
#endif /* not lint */
|
|
|
|
#ifndef lint
|
|
/*static char sccsid[] = "from: @(#)arp.c 8.2 (Berkeley) 1/2/94";*/
|
|
static char *rcsid = "$NetBSD: arp.c,v 1.12 1995/04/24 13:25:18 cgd Exp $";
|
|
#endif /* not lint */
|
|
|
|
/*
|
|
* arp - display, set, and delete arp table entries
|
|
*/
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/file.h>
|
|
#include <sys/socket.h>
|
|
#include <sys/sysctl.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 <netdb.h>
|
|
#include <errno.h>
|
|
#include <err.h>
|
|
#include <nlist.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <paths.h>
|
|
|
|
int delete __P((const char *, const char *));
|
|
void dump __P((u_long));
|
|
int ether_aton __P((const char *, u_char *));
|
|
void ether_print __P((const u_char *));
|
|
int file __P((char *));
|
|
void get __P((const char *));
|
|
int getinetaddr __P((const char *, struct in_addr *));
|
|
void getsocket __P((void));
|
|
int rtmsg __P((int));
|
|
int set __P((int, char **));
|
|
void usage __P((void));
|
|
|
|
static int pid;
|
|
static int nflag;
|
|
static int s = -1;
|
|
|
|
int
|
|
main(argc, argv)
|
|
int argc;
|
|
char **argv;
|
|
{
|
|
int ch;
|
|
|
|
pid = getpid();
|
|
while ((ch = getopt(argc, argv, "andsf")) != EOF)
|
|
switch((char)ch) {
|
|
case 'a':
|
|
dump(0);
|
|
return (0);
|
|
case 'd':
|
|
if (argc < 3 || argc > 4)
|
|
usage();
|
|
(void)delete(argv[2], argv[3]);
|
|
return (0);
|
|
case 'n':
|
|
nflag = 1;
|
|
break;
|
|
case 's':
|
|
if (argc < 4 || argc > 7)
|
|
usage();
|
|
return (set(argc-2, &argv[2]) ? 1 : 0);
|
|
case 'f':
|
|
if (argc != 3)
|
|
usage();
|
|
return (file(argv[2]));
|
|
case '?':
|
|
default:
|
|
usage();
|
|
}
|
|
if (argc == 2 || (argc == 3 && nflag))
|
|
get(argv[argc - 1]);
|
|
else
|
|
usage();
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Process a file to set standard arp entries
|
|
*/
|
|
int
|
|
file(name)
|
|
char *name;
|
|
{
|
|
char line[100], arg[5][50], *args[5];
|
|
int i, retval;
|
|
FILE *fp;
|
|
|
|
if ((fp = fopen(name, "r")) == NULL)
|
|
err(1, "cannot open %s", name);
|
|
args[0] = &arg[0][0];
|
|
args[1] = &arg[1][0];
|
|
args[2] = &arg[2][0];
|
|
args[3] = &arg[3][0];
|
|
args[4] = &arg[4][0];
|
|
retval = 0;
|
|
while (fgets(line, 100, fp) != NULL) {
|
|
i = sscanf(line, "%s %s %s %s %s", arg[0], arg[1], arg[2],
|
|
arg[3], arg[4]);
|
|
if (i < 2) {
|
|
warnx("bad line: %s", line);
|
|
retval = 1;
|
|
continue;
|
|
}
|
|
if (set(i, args))
|
|
retval = 1;
|
|
}
|
|
fclose(fp);
|
|
return (retval);
|
|
}
|
|
|
|
void
|
|
getsocket()
|
|
{
|
|
if (s >= 0)
|
|
return;
|
|
s = socket(PF_ROUTE, SOCK_RAW, 0);
|
|
if (s < 0)
|
|
err(1, "socket");
|
|
}
|
|
|
|
struct sockaddr_in so_mask = {8, 0, 0, { 0xffffffff}};
|
|
struct sockaddr_inarp blank_sin = {sizeof(blank_sin), AF_INET }, sin_m;
|
|
struct sockaddr_dl blank_sdl = {sizeof(blank_sdl), AF_LINK }, sdl_m;
|
|
int expire_time, flags, export_only, doing_proxy, found_entry;
|
|
struct {
|
|
struct rt_msghdr m_rtm;
|
|
char m_space[512];
|
|
} m_rtmsg;
|
|
|
|
/*
|
|
* Set an individual arp entry
|
|
*/
|
|
int
|
|
set(argc, argv)
|
|
int argc;
|
|
char **argv;
|
|
{
|
|
register struct sockaddr_inarp *sin;
|
|
register struct sockaddr_dl *sdl;
|
|
register struct rt_msghdr *rtm;
|
|
u_char *ea;
|
|
char *host = argv[0], *eaddr;
|
|
|
|
sin = &sin_m;
|
|
rtm = &(m_rtmsg.m_rtm);
|
|
eaddr = argv[1];
|
|
|
|
getsocket();
|
|
argc -= 2;
|
|
argv += 2;
|
|
sdl_m = blank_sdl; /* struct copy */
|
|
sin_m = blank_sin; /* struct copy */
|
|
if (getinetaddr(host, &sin->sin_addr) == -1)
|
|
return (1);
|
|
ea = (u_char *)LLADDR(&sdl_m);
|
|
if (ether_aton(eaddr, ea) == 0)
|
|
sdl_m.sdl_alen = 6;
|
|
doing_proxy = flags = export_only = expire_time = 0;
|
|
while (argc-- > 0) {
|
|
if (strncmp(argv[0], "temp", 4) == 0) {
|
|
struct timeval time;
|
|
(void)gettimeofday(&time, 0);
|
|
expire_time = time.tv_sec + 20 * 60;
|
|
}
|
|
else if (strncmp(argv[0], "pub", 3) == 0) {
|
|
flags |= RTF_ANNOUNCE;
|
|
doing_proxy = SIN_PROXY;
|
|
} else if (strncmp(argv[0], "trail", 5) == 0) {
|
|
(void)printf(
|
|
"%s: Sending trailers is no longer supported\n",
|
|
host);
|
|
}
|
|
argv++;
|
|
}
|
|
tryagain:
|
|
if (rtmsg(RTM_GET) < 0) {
|
|
warn("%s", host);
|
|
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:
|
|
goto overwrite;
|
|
}
|
|
if (doing_proxy == 0) {
|
|
(void)printf("set: can only proxy for %s\n", host);
|
|
return (1);
|
|
}
|
|
if (sin_m.sin_other & SIN_PROXY) {
|
|
(void)printf(
|
|
"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) {
|
|
(void)printf("cannot intuit interface index and type for %s\n",
|
|
host);
|
|
return (1);
|
|
}
|
|
sdl_m.sdl_type = sdl->sdl_type;
|
|
sdl_m.sdl_index = sdl->sdl_index;
|
|
return (rtmsg(RTM_ADD));
|
|
}
|
|
|
|
/*
|
|
* Display an individual arp entry
|
|
*/
|
|
void
|
|
get(host)
|
|
const char *host;
|
|
{
|
|
struct sockaddr_inarp *sin;
|
|
u_char *ea;
|
|
|
|
sin = &sin_m;
|
|
sin_m = blank_sin; /* struct copy */
|
|
if (getinetaddr(host, &sin->sin_addr) == -1)
|
|
exit(1);
|
|
dump(sin->sin_addr.s_addr);
|
|
if (found_entry == 0) {
|
|
(void)printf("%s (%s) -- no entry\n", host,
|
|
inet_ntoa(sin->sin_addr));
|
|
exit(1);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Delete an arp entry
|
|
*/
|
|
int
|
|
delete(host, info)
|
|
const char *host;
|
|
const char *info;
|
|
{
|
|
register struct sockaddr_inarp *sin;
|
|
register struct rt_msghdr *rtm;
|
|
struct sockaddr_dl *sdl;
|
|
u_char *ea;
|
|
char *eaddr;
|
|
|
|
sin = &sin_m;
|
|
rtm = &m_rtmsg.m_rtm;
|
|
|
|
if (info && strncmp(info, "pro", 3) )
|
|
export_only = 1;
|
|
getsocket();
|
|
sin_m = blank_sin; /* struct copy */
|
|
if (getinetaddr(host, &sin->sin_addr) == -1)
|
|
return (1);
|
|
tryagain:
|
|
if (rtmsg(RTM_GET) < 0) {
|
|
warn("%s", host);
|
|
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:
|
|
goto delete;
|
|
}
|
|
}
|
|
if (sin_m.sin_other & SIN_PROXY) {
|
|
warnx("delete: can't locate %s", host);
|
|
return (1);
|
|
} else {
|
|
sin_m.sin_other = SIN_PROXY;
|
|
goto tryagain;
|
|
}
|
|
delete:
|
|
if (sdl->sdl_family != AF_LINK) {
|
|
(void)printf("cannot locate %s\n", host);
|
|
return (1);
|
|
}
|
|
if (rtmsg(RTM_DELETE))
|
|
return (1);
|
|
(void)printf("%s (%s) deleted\n", host, inet_ntoa(sin->sin_addr));
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Dump the entire arp table
|
|
*/
|
|
void
|
|
dump(addr)
|
|
u_long addr;
|
|
{
|
|
int mib[6];
|
|
size_t needed;
|
|
char *host, *lim, *buf, *next;
|
|
struct rt_msghdr *rtm;
|
|
struct sockaddr_inarp *sin;
|
|
struct sockaddr_dl *sdl;
|
|
extern int h_errno;
|
|
struct hostent *hp;
|
|
|
|
mib[0] = CTL_NET;
|
|
mib[1] = PF_ROUTE;
|
|
mib[2] = 0;
|
|
mib[3] = AF_INET;
|
|
mib[4] = NET_RT_FLAGS;
|
|
mib[5] = RTF_LLINFO;
|
|
if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0)
|
|
err(1, "route-sysctl-estimate");
|
|
if ((buf = malloc(needed)) == NULL)
|
|
err(1, "malloc");
|
|
if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0)
|
|
err(1, "actual retrieval of routing table");
|
|
lim = buf + needed;
|
|
for (next = buf; next < lim; next += rtm->rtm_msglen) {
|
|
rtm = (struct rt_msghdr *)next;
|
|
sin = (struct sockaddr_inarp *)(rtm + 1);
|
|
sdl = (struct sockaddr_dl *)(sin + 1);
|
|
if (addr) {
|
|
if (addr != sin->sin_addr.s_addr)
|
|
continue;
|
|
found_entry = 1;
|
|
}
|
|
if (nflag == 0)
|
|
hp = gethostbyaddr((caddr_t)&(sin->sin_addr),
|
|
sizeof sin->sin_addr, AF_INET);
|
|
else
|
|
hp = 0;
|
|
if (hp)
|
|
host = hp->h_name;
|
|
else {
|
|
host = "?";
|
|
if (h_errno == TRY_AGAIN)
|
|
nflag = 1;
|
|
}
|
|
(void)printf("%s (%s) at ", host, inet_ntoa(sin->sin_addr));
|
|
if (sdl->sdl_alen)
|
|
ether_print(LLADDR(sdl));
|
|
else
|
|
(void)printf("(incomplete)");
|
|
if (rtm->rtm_rmx.rmx_expire == 0)
|
|
(void)printf(" permanent");
|
|
if (sin->sin_other & SIN_PROXY)
|
|
(void)printf(" published (proxy only)");
|
|
if (rtm->rtm_addrs & RTA_NETMASK) {
|
|
sin = (struct sockaddr_inarp *)
|
|
(sdl->sdl_len + (char *)sdl);
|
|
if (sin->sin_addr.s_addr == 0xffffffff)
|
|
(void)printf(" published");
|
|
if (sin->sin_len != 8)
|
|
(void)printf("(wierd)");
|
|
}
|
|
(void)printf("\n");
|
|
}
|
|
}
|
|
|
|
void
|
|
ether_print(cp)
|
|
const u_char *cp;
|
|
{
|
|
(void)printf("%x:%x:%x:%x:%x:%x", cp[0], cp[1], cp[2], cp[3], cp[4],
|
|
cp[5]);
|
|
}
|
|
|
|
int
|
|
ether_aton(a, n)
|
|
const char *a;
|
|
u_char *n;
|
|
{
|
|
int i, o[6];
|
|
|
|
i = sscanf(a, "%x:%x:%x:%x:%x:%x", &o[0], &o[1], &o[2], &o[3], &o[4],
|
|
&o[5]);
|
|
if (i != 6) {
|
|
warnx("invalid Ethernet address '%s'", a);
|
|
return (1);
|
|
}
|
|
for (i=0; i<6; i++)
|
|
n[i] = o[i];
|
|
return (0);
|
|
}
|
|
|
|
void
|
|
usage()
|
|
{
|
|
(void)fprintf(stderr, "usage: arp [-n] hostname\n");
|
|
(void)fprintf(stderr, "usage: arp [-n] -a\n");
|
|
(void)fprintf(stderr, "usage: arp -d hostname\n");
|
|
(void)fprintf(stderr,
|
|
"usage: arp -s hostname ether_addr [temp] [pub]\n");
|
|
(void)fprintf(stderr, "usage: arp -f filename\n");
|
|
exit(1);
|
|
}
|
|
|
|
int
|
|
rtmsg(cmd)
|
|
int cmd;
|
|
{
|
|
static int seq;
|
|
int rlen;
|
|
register struct rt_msghdr *rtm;
|
|
register char *cp;
|
|
register int l;
|
|
|
|
rtm = &m_rtmsg.m_rtm;
|
|
cp = m_rtmsg.m_space;
|
|
errno = 0;
|
|
|
|
if (cmd == RTM_DELETE)
|
|
goto doit;
|
|
(void)memset(&m_rtmsg, 0, sizeof(m_rtmsg));
|
|
rtm->rtm_flags = flags;
|
|
rtm->rtm_version = RTM_VERSION;
|
|
|
|
switch (cmd) {
|
|
default:
|
|
errx(1, "internal wrong cmd");
|
|
/*NOTREACHED*/
|
|
case RTM_ADD:
|
|
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)) { \
|
|
(void)memcpy(cp, &s, 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;
|
|
doit:
|
|
l = rtm->rtm_msglen;
|
|
rtm->rtm_seq = ++seq;
|
|
rtm->rtm_type = cmd;
|
|
if ((rlen = write(s, (char *)&m_rtmsg, l)) < 0) {
|
|
if (errno != ESRCH || cmd != RTM_DELETE) {
|
|
warn("writing to routing socket");
|
|
return (-1);
|
|
}
|
|
}
|
|
do {
|
|
l = read(s, (char *)&m_rtmsg, sizeof(m_rtmsg));
|
|
} while (l > 0 && (rtm->rtm_seq != seq || rtm->rtm_pid != pid));
|
|
if (l < 0)
|
|
warn("read from routing socket");
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
getinetaddr(host, inap)
|
|
const char *host;
|
|
struct in_addr *inap;
|
|
{
|
|
extern char *__progname; /* Program name, from crt0. */
|
|
struct hostent *hp;
|
|
u_long addr;
|
|
|
|
if (inet_aton(host, inap) == 1)
|
|
return (0);
|
|
if ((hp = gethostbyname(host)) == NULL) {
|
|
(void)fprintf(stderr, "%s: %s: ", __progname, host);
|
|
herror(NULL);
|
|
return (-1);
|
|
}
|
|
(void)memcpy(inap, hp->h_addr, sizeof(*inap));
|
|
return (0);
|
|
}
|