628d2ac1b0
do it themselves. (Some of these programs actually depended on this beyond compiling the definition of struct ifinfo!) Also fix up some other #include messes while we're at it.
651 lines
15 KiB
C
651 lines
15 KiB
C
/*
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* Copyright (c) 1984, 1993
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* The Regents of the University of California. All rights reserved.
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*
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* This code is derived from software contributed to Berkeley by
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* Sun Microsystems, Inc.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by the University of
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* California, Berkeley and its contributors.
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* 4. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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#ifndef lint
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static char const copyright[] =
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"@(#) Copyright (c) 1984, 1993\n\
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The Regents of the University of California. All rights reserved.\n";
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#endif /* not lint */
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#ifndef lint
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static char const sccsid[] = "@(#)from: arp.c 8.2 (Berkeley) 1/2/94";
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static char const freebsdid[] = "$Id: arp.c,v 1.4 1996/02/08 21:05:52 phk Exp $";
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#endif /* not lint */
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/*
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* arp - display, set, and delete arp table entries
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*/
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#include <sys/param.h>
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#include <sys/file.h>
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#include <sys/socket.h>
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#include <sys/sockio.h>
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#include <sys/sysctl.h>
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#include <sys/ioctl.h>
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#include <sys/time.h>
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#include <net/if.h>
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#include <net/if_dl.h>
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#include <net/if_types.h>
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#include <net/route.h>
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#include <netinet/in.h>
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#include <netinet/if_ether.h>
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#include <arpa/inet.h>
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#include <netdb.h>
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#include <errno.h>
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#include <nlist.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <unistd.h>
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#include <strings.h>
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#include <paths.h>
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void dump(u_long addr);
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int delete(char *host, char *info);
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void ether_print(u_char *cp);
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void usage(void);
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int set(int argc, char **argv);
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void get(char *host);
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int file(char *name);
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void getsocket(void);
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int ether_aton(char *a, u_char *n);
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int rtmsg(int cmd);
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void quit(char *msg);
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int get_ether_addr(u_long ipaddr, u_char *hwaddr);
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static int pid;
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static int nflag;
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static int s = -1;
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int
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main(argc, argv)
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int argc;
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char **argv;
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{
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int ch;
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pid = getpid();
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while ((ch = getopt(argc, argv, "andfsS")) != EOF)
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switch((char)ch) {
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case 'a':
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dump(0);
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exit(0);
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case 'd':
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if (argc < 3 || argc > 4)
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usage();
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delete(argv[2], argv[3]);
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exit(0);
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case 'n':
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nflag = 1;
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continue;
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case 'S':
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delete(argv[2], NULL);
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/* FALL THROUGH */
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case 's':
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if (argc < 4 || argc > 7)
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usage();
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exit(set(argc-2, &argv[2]) ? 1 : 0);
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case 'f' :
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if (argc != 3)
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usage();
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return (file(argv[2]));
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case '?':
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default:
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usage();
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}
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if (argc != 2)
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usage();
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get(argv[1]);
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exit(0);
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}
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/*
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* Process a file to set standard arp entries
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*/
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int
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file(char *name)
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{
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FILE *fp;
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int i, retval;
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char line[100], arg[5][50], *args[5];
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if ((fp = fopen(name, "r")) == NULL) {
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fprintf(stderr, "arp: cannot open %s\n", name);
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exit(1);
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}
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args[0] = &arg[0][0];
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args[1] = &arg[1][0];
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args[2] = &arg[2][0];
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args[3] = &arg[3][0];
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args[4] = &arg[4][0];
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retval = 0;
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while(fgets(line, 100, fp) != NULL) {
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i = sscanf(line, "%s %s %s %s %s", arg[0], arg[1], arg[2],
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arg[3], arg[4]);
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if (i < 2) {
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fprintf(stderr, "arp: bad line: %s\n", line);
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retval = 1;
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continue;
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}
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if (set(i, args))
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retval = 1;
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}
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fclose(fp);
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return (retval);
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}
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void
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getsocket(void)
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{
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if (s < 0) {
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s = socket(PF_ROUTE, SOCK_RAW, 0);
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if (s < 0) {
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perror("arp: socket");
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exit(1);
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}
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}
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}
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struct sockaddr_in so_mask = {8, 0, 0, { 0xffffffff}};
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struct sockaddr_inarp blank_sin = {sizeof(blank_sin), AF_INET }, sin_m;
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struct sockaddr_dl blank_sdl = {sizeof(blank_sdl), AF_LINK }, sdl_m;
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int expire_time, flags, export_only, doing_proxy, found_entry;
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struct {
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struct rt_msghdr m_rtm;
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char m_space[512];
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} m_rtmsg;
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/*
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* Set an individual arp entry
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*/
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int
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set(int argc, char **argv)
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{
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struct hostent *hp;
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register struct sockaddr_inarp *sin = &sin_m;
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register struct sockaddr_dl *sdl;
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register struct rt_msghdr *rtm = &(m_rtmsg.m_rtm);
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u_char *ea;
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char *host = argv[0], *eaddr = argv[1];
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getsocket();
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argc -= 2;
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argv += 2;
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sdl_m = blank_sdl;
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sin_m = blank_sin;
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sin->sin_addr.s_addr = inet_addr(host);
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if (sin->sin_addr.s_addr == -1) {
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if (!(hp = gethostbyname(host))) {
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fprintf(stderr, "arp: %s: ", host);
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herror((char *)NULL);
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return (1);
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}
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bcopy((char *)hp->h_addr, (char *)&sin->sin_addr,
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sizeof sin->sin_addr);
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}
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doing_proxy = flags = export_only = expire_time = 0;
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while (argc-- > 0) {
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if (strncmp(argv[0], "temp", 4) == 0) {
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struct timeval time;
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gettimeofday(&time, 0);
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expire_time = time.tv_sec + 20 * 60;
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}
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else if (strncmp(argv[0], "pub", 3) == 0) {
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flags |= RTF_ANNOUNCE;
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doing_proxy = SIN_PROXY;
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} else if (strncmp(argv[0], "trail", 5) == 0) {
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printf("%s: Sending trailers is no longer supported\n",
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host);
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}
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argv++;
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}
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ea = (u_char *)LLADDR(&sdl_m);
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if (doing_proxy && !strcmp(eaddr, "auto")) {
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if (!get_ether_addr(sin->sin_addr.s_addr, ea)) {
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return (1);
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}
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sdl_m.sdl_alen = 6;
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} else {
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if (ether_aton(eaddr, ea) == 0)
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sdl_m.sdl_alen = 6;
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}
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tryagain:
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if (rtmsg(RTM_GET) < 0) {
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perror(host);
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return (1);
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}
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sin = (struct sockaddr_inarp *)(rtm + 1);
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sdl = (struct sockaddr_dl *)(sin->sin_len + (char *)sin);
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if (sin->sin_addr.s_addr == sin_m.sin_addr.s_addr) {
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if (sdl->sdl_family == AF_LINK &&
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(rtm->rtm_flags & RTF_LLINFO) &&
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!(rtm->rtm_flags & RTF_GATEWAY)) switch (sdl->sdl_type) {
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case IFT_ETHER: case IFT_FDDI: case IFT_ISO88023:
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case IFT_ISO88024: case IFT_ISO88025:
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goto overwrite;
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}
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if (doing_proxy == 0) {
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printf("set: can only proxy for %s\n", host);
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return (1);
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}
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if (sin_m.sin_other & SIN_PROXY) {
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printf("set: proxy entry exists for non 802 device\n");
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return(1);
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}
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sin_m.sin_other = SIN_PROXY;
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export_only = 1;
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goto tryagain;
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}
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overwrite:
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if (sdl->sdl_family != AF_LINK) {
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printf("cannot intuit interface index and type for %s\n", host);
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return (1);
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}
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sdl_m.sdl_type = sdl->sdl_type;
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sdl_m.sdl_index = sdl->sdl_index;
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return (rtmsg(RTM_ADD));
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}
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/*
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* Display an individual arp entry
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*/
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void
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get(char *host)
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{
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struct hostent *hp;
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struct sockaddr_inarp *sin = &sin_m;
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sin_m = blank_sin;
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sin->sin_addr.s_addr = inet_addr(host);
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if (sin->sin_addr.s_addr == -1) {
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if (!(hp = gethostbyname(host))) {
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fprintf(stderr, "arp: %s: ", host);
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herror((char *)NULL);
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exit(1);
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}
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bcopy((char *)hp->h_addr, (char *)&sin->sin_addr,
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sizeof sin->sin_addr);
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}
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dump(sin->sin_addr.s_addr);
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if (found_entry == 0) {
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printf("%s (%s) -- no entry\n",
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host, inet_ntoa(sin->sin_addr));
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exit(1);
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}
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}
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/*
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* Delete an arp entry
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*/
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int
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delete(char *host, char *info)
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{
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struct hostent *hp;
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register struct sockaddr_inarp *sin = &sin_m;
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register struct rt_msghdr *rtm = &m_rtmsg.m_rtm;
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struct sockaddr_dl *sdl;
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if (info && strncmp(info, "pro", 3) )
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export_only = 1;
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getsocket();
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sin_m = blank_sin;
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sin->sin_addr.s_addr = inet_addr(host);
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if (sin->sin_addr.s_addr == -1) {
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if (!(hp = gethostbyname(host))) {
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fprintf(stderr, "arp: %s: ", host);
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herror((char *)NULL);
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return (1);
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}
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bcopy((char *)hp->h_addr, (char *)&sin->sin_addr,
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sizeof sin->sin_addr);
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}
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tryagain:
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if (rtmsg(RTM_GET) < 0) {
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perror(host);
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return (1);
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}
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sin = (struct sockaddr_inarp *)(rtm + 1);
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sdl = (struct sockaddr_dl *)(sin->sin_len + (char *)sin);
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if (sin->sin_addr.s_addr == sin_m.sin_addr.s_addr) {
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if (sdl->sdl_family == AF_LINK &&
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(rtm->rtm_flags & RTF_LLINFO) &&
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!(rtm->rtm_flags & RTF_GATEWAY)) switch (sdl->sdl_type) {
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case IFT_ETHER: case IFT_FDDI: case IFT_ISO88023:
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case IFT_ISO88024: case IFT_ISO88025:
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goto delete;
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}
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}
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if (sin_m.sin_other & SIN_PROXY) {
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fprintf(stderr, "delete: can't locate %s\n",host);
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return (1);
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} else {
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sin_m.sin_other = SIN_PROXY;
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goto tryagain;
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}
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delete:
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if (sdl->sdl_family != AF_LINK) {
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printf("cannot locate %s\n", host);
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return (1);
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}
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if (rtmsg(RTM_DELETE) == 0) {
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printf("%s (%s) deleted\n", host, inet_ntoa(sin->sin_addr));
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return (0);
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}
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return (1);
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}
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/*
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* Dump the entire arp table
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*/
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void
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dump(u_long addr)
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{
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int mib[6];
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size_t needed;
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char *host, *malloc(), *lim, *buf, *next;
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struct rt_msghdr *rtm;
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struct sockaddr_inarp *sin;
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struct sockaddr_dl *sdl;
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extern int h_errno;
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struct hostent *hp;
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mib[0] = CTL_NET;
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mib[1] = PF_ROUTE;
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mib[2] = 0;
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mib[3] = AF_INET;
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mib[4] = NET_RT_FLAGS;
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mib[5] = RTF_LLINFO;
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if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0)
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quit("route-sysctl-estimate");
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if ((buf = malloc(needed)) == NULL)
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quit("malloc");
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if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0)
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quit("actual retrieval of routing table");
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lim = buf + needed;
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for (next = buf; next < lim; next += rtm->rtm_msglen) {
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rtm = (struct rt_msghdr *)next;
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sin = (struct sockaddr_inarp *)(rtm + 1);
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sdl = (struct sockaddr_dl *)(sin + 1);
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if (addr) {
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if (addr != sin->sin_addr.s_addr)
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continue;
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found_entry = 1;
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}
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if (nflag == 0)
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hp = gethostbyaddr((caddr_t)&(sin->sin_addr),
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sizeof sin->sin_addr, AF_INET);
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else
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hp = 0;
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if (hp)
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host = hp->h_name;
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else {
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host = "?";
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if (h_errno == TRY_AGAIN)
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nflag = 1;
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}
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printf("%s (%s) at ", host, inet_ntoa(sin->sin_addr));
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if (sdl->sdl_alen)
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ether_print(LLADDR(sdl));
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else
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printf("(incomplete)");
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if (rtm->rtm_rmx.rmx_expire == 0)
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printf(" permanent");
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if (sin->sin_other & SIN_PROXY)
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printf(" published (proxy only)");
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if (rtm->rtm_addrs & RTA_NETMASK) {
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sin = (struct sockaddr_inarp *)
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(sdl->sdl_len + (char *)sdl);
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if (sin->sin_addr.s_addr == 0xffffffff)
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printf(" published");
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if (sin->sin_len != 8)
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printf("(wierd)");
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}
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printf("\n");
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}
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}
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void
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ether_print(u_char *cp)
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{
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printf("%x:%x:%x:%x:%x:%x", cp[0], cp[1], cp[2], cp[3], cp[4], cp[5]);
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}
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int
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ether_aton(char *a, u_char *n)
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{
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int i, o[6];
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i = sscanf(a, "%x:%x:%x:%x:%x:%x", &o[0], &o[1], &o[2],
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&o[3], &o[4], &o[5]);
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if (i != 6) {
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fprintf(stderr, "arp: invalid Ethernet address '%s'\n", a);
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return (1);
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}
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for (i=0; i<6; i++)
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n[i] = o[i];
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return (0);
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}
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void
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usage(void)
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{
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printf("usage: arp hostname\n");
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printf(" arp -a [kernel] [kernel_memory]\n");
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printf(" arp -d hostname\n");
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printf(" arp -s hostname ether_addr [temp] [pub]\n");
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printf(" arp -S hostname ether_addr [temp] [pub]\n");
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printf(" arp -f filename\n");
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exit(1);
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}
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int
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rtmsg(int cmd)
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{
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static int seq;
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int rlen;
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register struct rt_msghdr *rtm = &m_rtmsg.m_rtm;
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register char *cp = m_rtmsg.m_space;
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register int l;
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errno = 0;
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if (cmd == RTM_DELETE)
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goto doit;
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bzero((char *)&m_rtmsg, sizeof(m_rtmsg));
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rtm->rtm_flags = flags;
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rtm->rtm_version = RTM_VERSION;
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switch (cmd) {
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default:
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fprintf(stderr, "arp: internal wrong cmd\n");
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exit(1);
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case RTM_ADD:
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rtm->rtm_addrs |= RTA_GATEWAY;
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rtm->rtm_rmx.rmx_expire = expire_time;
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rtm->rtm_inits = RTV_EXPIRE;
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rtm->rtm_flags |= (RTF_HOST | RTF_STATIC);
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sin_m.sin_other = 0;
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if (doing_proxy) {
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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;
|
|
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) {
|
|
perror("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)
|
|
(void) fprintf(stderr, "arp: read from routing socket: %s\n",
|
|
strerror(errno));
|
|
return (0);
|
|
}
|
|
|
|
void
|
|
quit(char *msg)
|
|
{
|
|
fprintf(stderr, "%s\n", msg);
|
|
exit(1);
|
|
}
|
|
|
|
/*
|
|
* get_ether_addr - get the hardware address of an interface on the
|
|
* the same subnet as ipaddr.
|
|
*/
|
|
#define MAX_IFS 32
|
|
|
|
int
|
|
get_ether_addr(u_long ipaddr, u_char *hwaddr)
|
|
{
|
|
struct ifreq *ifr, *ifend, *ifp;
|
|
u_long ina, mask;
|
|
struct sockaddr_dl *dla;
|
|
struct ifreq ifreq;
|
|
struct ifconf ifc;
|
|
struct ifreq ifs[MAX_IFS];
|
|
int s;
|
|
|
|
s = socket(AF_INET, SOCK_DGRAM, 0);
|
|
if (s < 0) {
|
|
perror("socket");
|
|
exit(1);
|
|
}
|
|
|
|
ifc.ifc_len = sizeof(ifs);
|
|
ifc.ifc_req = ifs;
|
|
if (ioctl(s, SIOCGIFCONF, &ifc) < 0) {
|
|
fprintf(stderr, "ioctl(SIOCGIFCONF): \n");
|
|
close(s);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Scan through looking for an interface with an Internet
|
|
* address on the same subnet as `ipaddr'.
|
|
*/
|
|
ifend = (struct ifreq *) (ifc.ifc_buf + ifc.ifc_len);
|
|
for (ifr = ifc.ifc_req; ifr < ifend; ) {
|
|
if (ifr->ifr_addr.sa_family == AF_INET) {
|
|
ina = ((struct sockaddr_in *)
|
|
&ifr->ifr_addr)->sin_addr.s_addr;
|
|
strncpy(ifreq.ifr_name, ifr->ifr_name,
|
|
sizeof(ifreq.ifr_name));
|
|
/*
|
|
* Check that the interface is up,
|
|
* and not point-to-point or loopback.
|
|
*/
|
|
if (ioctl(s, SIOCGIFFLAGS, &ifreq) < 0)
|
|
continue;
|
|
if ((ifreq.ifr_flags &
|
|
(IFF_UP|IFF_BROADCAST|IFF_POINTOPOINT|
|
|
IFF_LOOPBACK|IFF_NOARP))
|
|
!= (IFF_UP|IFF_BROADCAST))
|
|
goto nextif;
|
|
/*
|
|
* Get its netmask and check that it's on
|
|
* the right subnet.
|
|
*/
|
|
if (ioctl(s, SIOCGIFNETMASK, &ifreq) < 0)
|
|
continue;
|
|
mask = ((struct sockaddr_in *)
|
|
&ifreq.ifr_addr)->sin_addr.s_addr;
|
|
if ((ipaddr & mask) != (ina & mask))
|
|
goto nextif;
|
|
break;
|
|
}
|
|
nextif:
|
|
ifr = (struct ifreq *)
|
|
((char *)&ifr->ifr_addr + ifr->ifr_addr.sa_len);
|
|
}
|
|
|
|
if (ifr >= ifend) {
|
|
close(s);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Now scan through again looking for a link-level address
|
|
* for this interface.
|
|
*/
|
|
ifp = ifr;
|
|
for (ifr = ifc.ifc_req; ifr < ifend; ) {
|
|
if (strcmp(ifp->ifr_name, ifr->ifr_name) == 0
|
|
&& ifr->ifr_addr.sa_family == AF_LINK) {
|
|
/*
|
|
* Found the link-level address - copy it out
|
|
*/
|
|
dla = (struct sockaddr_dl *) &ifr->ifr_addr;
|
|
memcpy(hwaddr, LLADDR(dla), dla->sdl_alen);
|
|
close (s);
|
|
printf("using interface %s for proxy with address ",
|
|
ifp->ifr_name);
|
|
ether_print(hwaddr);
|
|
printf("\n");
|
|
return dla->sdl_alen;
|
|
}
|
|
ifr = (struct ifreq *)
|
|
((char *)&ifr->ifr_addr + ifr->ifr_addr.sa_len);
|
|
}
|
|
return 0;
|
|
}
|