/* * Copyright (c) 1984 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 char copyright[] = "@(#) Copyright (c) 1984 Regents of the University of California.\n\ All rights reserved.\n"; #endif /* not lint */ #ifndef lint /*static char sccsid[] = "from: @(#)arp.c 5.11.1.1 (Berkeley) 7/22/91";*/ static char rcsid[] = "$Id: arp.c,v 1.3 1993/08/01 18:00:27 mycroft Exp $"; #endif /* not lint */ /* * arp - display, set, and delete arp table entries */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include extern int errno; main(argc, argv) int argc; char **argv; { int ch; while ((ch = getopt(argc, argv, "adsf")) != EOF) switch((char)ch) { case 'a': { char *mem = 0; if (argc > 4) usage(); if (argc == 4) { mem = argv[3]; } dump((argc >= 3) ? argv[2] : _PATH_UNIX, mem); exit(0); } case 'd': if (argc != 3) usage(); delete(argv[2]); exit(0); case 's': if (argc < 4 || argc > 7) usage(); exit(set(argc-2, &argv[2]) ? 1 : 0); case 'f': if (argc != 3) usage(); exit (file(argv[2]) ? 1 : 0); case '?': default: usage(); } if (argc != 2) usage(); get(argv[1]); exit(0); } /* * Process a file to set standard arp entries */ file(name) char *name; { FILE *fp; int i, retval; char line[100], arg[5][50], *args[5]; if ((fp = fopen(name, "r")) == NULL) { fprintf(stderr, "arp: cannot open %s\n", name); exit(1); } 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) { fprintf(stderr, "arp: bad line: %s\n", line); retval = 1; continue; } if (set(i, args)) retval = 1; } fclose(fp); return (retval); } /* * Set an individual arp entry */ set(argc, argv) int argc; char **argv; { struct arpreq ar; struct hostent *hp; struct sockaddr_in *sin; u_char *ea; int s; char *host = argv[0], *eaddr = argv[1]; argc -= 2; argv += 2; bzero((caddr_t)&ar, sizeof ar); sin = (struct sockaddr_in *)&ar.arp_pa; sin->sin_family = AF_INET; sin->sin_addr.s_addr = inet_addr(host); if (sin->sin_addr.s_addr == -1) { if (!(hp = gethostbyname(host))) { fprintf(stderr, "arp: %s: ", host); herror((char *)NULL); return (1); } bcopy((char *)hp->h_addr, (char *)&sin->sin_addr, sizeof sin->sin_addr); } ea = (u_char *)ar.arp_ha.sa_data; if (ether_aton(eaddr, ea)) return (1); ar.arp_flags = ATF_PERM; while (argc-- > 0) { if (strncmp(argv[0], "temp", 4) == 0) ar.arp_flags &= ~ATF_PERM; else if (strncmp(argv[0], "pub", 3) == 0) ar.arp_flags |= ATF_PUBL; else if (strncmp(argv[0], "trail", 5) == 0) ar.arp_flags |= ATF_USETRAILERS; argv++; } s = socket(AF_INET, SOCK_DGRAM, 0); if (s < 0) { perror("arp: socket"); exit(1); } if (ioctl(s, SIOCSARP, (caddr_t)&ar) < 0) { perror(host); exit(1); } close(s); return (0); } /* * Display an individual arp entry */ get(host) char *host; { struct arpreq ar; struct hostent *hp; struct sockaddr_in *sin; u_char *ea; int s; bzero((caddr_t)&ar, sizeof ar); ar.arp_pa.sa_family = AF_INET; sin = (struct sockaddr_in *)&ar.arp_pa; sin->sin_family = AF_INET; sin->sin_addr.s_addr = inet_addr(host); if (sin->sin_addr.s_addr == -1) { if (!(hp = gethostbyname(host))) { fprintf(stderr, "arp: %s: ", host); herror((char *)NULL); exit(1); } bcopy((char *)hp->h_addr, (char *)&sin->sin_addr, sizeof sin->sin_addr); } s = socket(AF_INET, SOCK_DGRAM, 0); if (s < 0) { perror("arp: socket"); exit(1); } if (ioctl(s, SIOCGARP, (caddr_t)&ar) < 0) { if (errno == ENXIO) printf("%s (%s) -- no entry\n", host, inet_ntoa(sin->sin_addr)); else perror("SIOCGARP"); exit(1); } close(s); ea = (u_char *)ar.arp_ha.sa_data; printf("%s (%s) at ", host, inet_ntoa(sin->sin_addr)); if (ar.arp_flags & ATF_COM) ether_print(ea); else printf("(incomplete)"); if (ar.arp_flags & ATF_PERM) printf(" permanent"); if (ar.arp_flags & ATF_PUBL) printf(" published"); if (ar.arp_flags & ATF_USETRAILERS) printf(" trailers"); printf("\n"); } /* * Delete an arp entry */ delete(host) char *host; { struct arpreq ar; struct hostent *hp; struct sockaddr_in *sin; int s; bzero((caddr_t)&ar, sizeof ar); ar.arp_pa.sa_family = AF_INET; sin = (struct sockaddr_in *)&ar.arp_pa; sin->sin_family = AF_INET; sin->sin_addr.s_addr = inet_addr(host); if (sin->sin_addr.s_addr == -1) { if (!(hp = gethostbyname(host))) { fprintf(stderr, "arp: %s: ", host); herror((char *)NULL); exit(1); } bcopy((char *)hp->h_addr, (char *)&sin->sin_addr, sizeof sin->sin_addr); } s = socket(AF_INET, SOCK_DGRAM, 0); if (s < 0) { perror("arp: socket"); exit(1); } if (ioctl(s, SIOCDARP, (caddr_t)&ar) < 0) { if (errno == ENXIO) printf("%s (%s) -- no entry\n", host, inet_ntoa(sin->sin_addr)); else perror("SIOCDARP"); exit(1); } close(s); printf("%s (%s) deleted\n", host, inet_ntoa(sin->sin_addr)); } struct nlist nl[] = { #define X_ARPTAB 0 { "_arptab" }, #define X_ARPTAB_SIZE 1 { "_arptab_size" }, { "" }, }; /* * Dump the entire arp table */ dump(kernel, mem) char *kernel, *mem; { extern int h_errno; struct arptab *at; struct hostent *hp; int bynumber, mf, arptab_size, sz; char *host, *malloc(); off_t lseek(); if (kvm_openfiles(kernel, mem, NULL) == -1) { fprintf(stderr, "arp: kvm_openfiles: %s\n", kvm_geterr()); exit(1); } if (kvm_nlist(nl) < 0 || nl[X_ARPTAB_SIZE].n_type == 0) { fprintf(stderr, "arp: %s: bad namelist\n", kernel); exit(1); } if (kvm_read((void *)(nl[X_ARPTAB_SIZE].n_value), &arptab_size, sizeof arptab_size) == -1 || arptab_size <= 0 || arptab_size > 1000) { fprintf(stderr, "arp: %s: namelist wrong\n", kernel); exit(1); } sz = arptab_size * sizeof (struct arptab); at = (struct arptab *)malloc((u_int)sz); if (at == NULL) { fputs("arp: can't get memory for arptab.\n", stderr); exit(1); } if (kvm_read((void *)(nl[X_ARPTAB].n_value), (char *)at, sz) == -1) { perror("arp: error reading arptab"); exit(1); } for (bynumber = 0; arptab_size-- > 0; at++) { if (at->at_iaddr.s_addr == 0 || at->at_flags == 0) continue; if (bynumber == 0) hp = gethostbyaddr((caddr_t)&at->at_iaddr, sizeof at->at_iaddr, AF_INET); else hp = 0; if (hp) host = hp->h_name; else { host = "?"; if (h_errno == TRY_AGAIN) bynumber = 1; } printf("%s (%s) at ", host, inet_ntoa(at->at_iaddr)); if (at->at_flags & ATF_COM) ether_print(at->at_enaddr); else printf("(incomplete)"); if (at->at_flags & ATF_PERM) printf(" permanent"); if (at->at_flags & ATF_PUBL) printf(" published"); if (at->at_flags & ATF_USETRAILERS) printf(" trailers"); printf("\n"); } } ether_print(cp) u_char *cp; { printf("%x:%x:%x:%x:%x:%x", cp[0], cp[1], cp[2], cp[3], cp[4], cp[5]); } ether_aton(a, n) 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) { fprintf(stderr, "arp: invalid Ethernet address '%s'\n", a); return (1); } for (i=0; i<6; i++) n[i] = o[i]; return (0); } usage() { printf("usage: arp hostname\n"); printf(" arp -a [kernel] [kernel_memory]\n"); printf(" arp -d hostname\n"); printf(" arp -s hostname ether_addr [temp] [pub] [trail]\n"); printf(" arp -f filename\n"); exit(1); }