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authorTheo de Raadt <deraadt@cvs.openbsd.org>1995-10-18 08:53:40 +0000
committerTheo de Raadt <deraadt@cvs.openbsd.org>1995-10-18 08:53:40 +0000
commitd6583bb2a13f329cf0332ef2570eb8bb8fc0e39c (patch)
treeece253b876159b39c620e62b6c9b1174642e070e /usr.sbin/arp/arp.c
initial import of NetBSD tree
Diffstat (limited to 'usr.sbin/arp/arp.c')
-rw-r--r--usr.sbin/arp/arp.c544
1 files changed, 544 insertions, 0 deletions
diff --git a/usr.sbin/arp/arp.c b/usr.sbin/arp/arp.c
new file mode 100644
index 00000000000..6198ad7a22d
--- /dev/null
+++ b/usr.sbin/arp/arp.c
@@ -0,0 +1,544 @@
+/* $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);
+}