arp.c revision 111910
11553Srgrimes/* 21553Srgrimes * Copyright (c) 1984, 1993 31553Srgrimes * The Regents of the University of California. All rights reserved. 41553Srgrimes * 51553Srgrimes * This code is derived from software contributed to Berkeley by 61553Srgrimes * Sun Microsystems, Inc. 71553Srgrimes * 81553Srgrimes * Redistribution and use in source and binary forms, with or without 91553Srgrimes * modification, are permitted provided that the following conditions 101553Srgrimes * are met: 111553Srgrimes * 1. Redistributions of source code must retain the above copyright 121553Srgrimes * notice, this list of conditions and the following disclaimer. 131553Srgrimes * 2. Redistributions in binary form must reproduce the above copyright 141553Srgrimes * notice, this list of conditions and the following disclaimer in the 151553Srgrimes * documentation and/or other materials provided with the distribution. 161553Srgrimes * 3. All advertising materials mentioning features or use of this software 171553Srgrimes * must display the following acknowledgement: 181553Srgrimes * This product includes software developed by the University of 191553Srgrimes * California, Berkeley and its contributors. 201553Srgrimes * 4. Neither the name of the University nor the names of its contributors 211553Srgrimes * may be used to endorse or promote products derived from this software 221553Srgrimes * without specific prior written permission. 231553Srgrimes * 241553Srgrimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 251553Srgrimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 261553Srgrimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 271553Srgrimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 281553Srgrimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 291553Srgrimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 301553Srgrimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 311553Srgrimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 321553Srgrimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 331553Srgrimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 341553Srgrimes * SUCH DAMAGE. 351553Srgrimes */ 361553Srgrimes 371553Srgrimes#ifndef lint 3813977Sphkstatic char const copyright[] = 391553Srgrimes"@(#) Copyright (c) 1984, 1993\n\ 401553Srgrimes The Regents of the University of California. All rights reserved.\n"; 411553Srgrimes#endif /* not lint */ 421553Srgrimes 431553Srgrimes#ifndef lint 4429060Scharnier#if 0 4513977Sphkstatic char const sccsid[] = "@(#)from: arp.c 8.2 (Berkeley) 1/2/94"; 4629060Scharnier#endif 4729060Scharnierstatic const char rcsid[] = 4850479Speter "$FreeBSD: head/usr.sbin/arp/arp.c 111910 2003-03-05 15:53:18Z ru $"; 491553Srgrimes#endif /* not lint */ 501553Srgrimes 511553Srgrimes/* 521553Srgrimes * arp - display, set, and delete arp table entries 531553Srgrimes */ 541553Srgrimes 551553Srgrimes 561553Srgrimes#include <sys/param.h> 571553Srgrimes#include <sys/file.h> 581553Srgrimes#include <sys/socket.h> 5913977Sphk#include <sys/sockio.h> 601553Srgrimes#include <sys/sysctl.h> 6113977Sphk#include <sys/ioctl.h> 6220287Swollman#include <sys/time.h> 631553Srgrimes 641553Srgrimes#include <net/if.h> 651553Srgrimes#include <net/if_dl.h> 661553Srgrimes#include <net/if_types.h> 6796235Swpaul#include <net/route.h> 6896202Skbyanc#include <net/iso88025.h> 691553Srgrimes 701553Srgrimes#include <netinet/in.h> 711553Srgrimes#include <netinet/if_ether.h> 721553Srgrimes 731553Srgrimes#include <arpa/inet.h> 741553Srgrimes 75108314Sru#include <ctype.h> 7629060Scharnier#include <err.h> 7729060Scharnier#include <errno.h> 781553Srgrimes#include <netdb.h> 791553Srgrimes#include <nlist.h> 8029060Scharnier#include <paths.h> 811553Srgrimes#include <stdio.h> 8213977Sphk#include <stdlib.h> 8393590Smike#include <string.h> 8429060Scharnier#include <strings.h> 8513977Sphk#include <unistd.h> 861553Srgrimes 8731145Sjulianvoid search(u_long addr, void (*action)(struct sockaddr_dl *sdl, 8831145Sjulian struct sockaddr_inarp *sin, struct rt_msghdr *rtm)); 8931145Sjulianvoid print_entry(struct sockaddr_dl *sdl, 9087598Smikeh struct sockaddr_inarp *addr, struct rt_msghdr *rtm); 9131145Sjulianvoid nuke_entry(struct sockaddr_dl *sdl, 9287598Smikeh struct sockaddr_inarp *addr, struct rt_msghdr *rtm); 9313977Sphkint delete(char *host, char *info); 9413977Sphkvoid usage(void); 9513977Sphkint set(int argc, char **argv); 9631145Sjulianint get(char *host); 9713977Sphkint file(char *name); 9813977Sphkvoid getsocket(void); 9993952Sruint my_ether_aton(char *a, struct ether_addr *n); 10013977Sphkint rtmsg(int cmd); 10193952Sruint get_ether_addr(u_int32_t ipaddr, struct ether_addr *hwaddr); 10213977Sphk 103100650Sjmallettstatic pid_t pid; 10431145Sjulianstatic int nflag; /* no reverse dns lookups */ 10531145Sjulianstatic int aflag; /* do it for all entries */ 1061553Srgrimesstatic int s = -1; 1071553Srgrimes 10887598Smikehstruct sockaddr_in so_mask; 10987598Smikehstruct sockaddr_inarp blank_sin, sin_m; 11087598Smikehstruct sockaddr_dl blank_sdl, sdl_m; 11187598Smikehint expire_time, flags, doing_proxy, proxy_only, found_entry; 11287598Smikehstruct { 11387598Smikeh struct rt_msghdr m_rtm; 11487598Smikeh char m_space[512]; 11587598Smikeh} m_rtmsg; 11687598Smikeh 11731145Sjulian/* which function we're supposed to do */ 11831145Sjulian#define F_GET 1 11931145Sjulian#define F_SET 2 12031145Sjulian#define F_FILESET 3 12131145Sjulian#define F_REPLACE 4 12231145Sjulian#define F_DELETE 5 12331145Sjulian 12451250Sru#define ROUNDUP(a) \ 12551250Sru ((a) > 0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long)) 12631145Sjulian#define SETFUNC(f) { if (func) usage(); func = (f); } 12731145Sjulian 12813977Sphkint 12977870Srumain(int argc, char *argv[]) 1301553Srgrimes{ 13131145Sjulian int ch, func = 0; 13231145Sjulian int rtn = 0; 1331553Srgrimes 1341553Srgrimes pid = getpid(); 13524428Simp while ((ch = getopt(argc, argv, "andfsS")) != -1) 1361553Srgrimes switch((char)ch) { 1371553Srgrimes case 'a': 13831145Sjulian aflag = 1; 13931145Sjulian break; 1401553Srgrimes case 'd': 14131145Sjulian SETFUNC(F_DELETE); 14231145Sjulian break; 1431553Srgrimes case 'n': 1441553Srgrimes nflag = 1; 14531145Sjulian break; 14613977Sphk case 'S': 14731145Sjulian SETFUNC(F_REPLACE); 14831145Sjulian break; 1491553Srgrimes case 's': 15031145Sjulian SETFUNC(F_SET); 15131145Sjulian break; 1529874Sjkh case 'f' : 15331145Sjulian SETFUNC(F_FILESET); 15431145Sjulian break; 1551553Srgrimes case '?': 1561553Srgrimes default: 1571553Srgrimes usage(); 1581553Srgrimes } 15931145Sjulian argc -= optind; 16031145Sjulian argv += optind; 16131145Sjulian 16287598Smikeh bzero(&so_mask, sizeof(so_mask)); 16392735Smikeh so_mask.sin_len = 8; 16487598Smikeh so_mask.sin_addr.s_addr = 0xffffffff; 16587598Smikeh bzero(&blank_sin, sizeof(blank_sin)); 16687598Smikeh blank_sin.sin_len = sizeof(blank_sin); 16787598Smikeh blank_sin.sin_family = AF_INET; 16887598Smikeh bzero(&blank_sdl, sizeof(blank_sdl)); 16987598Smikeh blank_sdl.sdl_len = sizeof(blank_sdl); 17087598Smikeh blank_sdl.sdl_family = AF_LINK; 17187598Smikeh 17231145Sjulian if (!func) 17331145Sjulian func = F_GET; 17431145Sjulian switch (func) { 17531145Sjulian case F_GET: 17631145Sjulian if (aflag) { 17731145Sjulian if (argc != 0) 17831145Sjulian usage(); 17931145Sjulian search(0, print_entry); 18031145Sjulian } else { 18131145Sjulian if (argc != 1) 18231145Sjulian usage(); 18331145Sjulian get(argv[0]); 18431145Sjulian } 18531145Sjulian break; 18631145Sjulian case F_SET: 18731145Sjulian case F_REPLACE: 18877870Sru if (argc < 2 || argc > 6) 18931145Sjulian usage(); 19031145Sjulian if (func == F_REPLACE) 19131145Sjulian (void) delete(argv[0], NULL); 19231145Sjulian rtn = set(argc, argv) ? 1 : 0; 19331145Sjulian break; 19431145Sjulian case F_DELETE: 19531145Sjulian if (aflag) { 19631145Sjulian if (argc != 0) 19731145Sjulian usage(); 19831145Sjulian search(0, nuke_entry); 19931145Sjulian } else { 20031145Sjulian if (argc < 1 || argc > 2) 20131145Sjulian usage(); 20231145Sjulian rtn = delete(argv[0], argv[1]); 20331145Sjulian } 20431145Sjulian break; 20531145Sjulian case F_FILESET: 20631145Sjulian if (argc != 1) 20731145Sjulian usage(); 20831145Sjulian rtn = file(argv[0]); 20931145Sjulian break; 21031145Sjulian } 21131145Sjulian 21231145Sjulian return(rtn); 2131553Srgrimes} 2141553Srgrimes 2151553Srgrimes/* 2161553Srgrimes * Process a file to set standard arp entries 2171553Srgrimes */ 21813977Sphkint 21913977Sphkfile(char *name) 2201553Srgrimes{ 2211553Srgrimes FILE *fp; 2221553Srgrimes int i, retval; 223109413Sru char line[100], arg[5][50], *args[5], *p; 2241553Srgrimes 22529060Scharnier if ((fp = fopen(name, "r")) == NULL) 22629060Scharnier errx(1, "cannot open %s", name); 2271553Srgrimes args[0] = &arg[0][0]; 2281553Srgrimes args[1] = &arg[1][0]; 2291553Srgrimes args[2] = &arg[2][0]; 2301553Srgrimes args[3] = &arg[3][0]; 2311553Srgrimes args[4] = &arg[4][0]; 2321553Srgrimes retval = 0; 2331553Srgrimes while(fgets(line, 100, fp) != NULL) { 234109413Sru if ((p = strchr(line, '#')) != NULL) 235109413Sru *p = '\0'; 236109413Sru for (p = line; isblank(*p); p++); 237111910Sru if (*p == '\n' || *p == '\0') 238108314Sru continue; 239109413Sru i = sscanf(p, "%49s %49s %49s %49s %49s", arg[0], arg[1], 24056134Sjkh arg[2], arg[3], arg[4]); 2411553Srgrimes if (i < 2) { 24229060Scharnier warnx("bad line: %s", line); 2431553Srgrimes retval = 1; 2441553Srgrimes continue; 2451553Srgrimes } 2461553Srgrimes if (set(i, args)) 2471553Srgrimes retval = 1; 2481553Srgrimes } 2491553Srgrimes fclose(fp); 2501553Srgrimes return (retval); 2511553Srgrimes} 2521553Srgrimes 25313977Sphkvoid 25413977Sphkgetsocket(void) 25513977Sphk{ 2561553Srgrimes if (s < 0) { 2571553Srgrimes s = socket(PF_ROUTE, SOCK_RAW, 0); 25829060Scharnier if (s < 0) 25929060Scharnier err(1, "socket"); 2601553Srgrimes } 2611553Srgrimes} 2621553Srgrimes 2631553Srgrimes/* 2648857Srgrimes * Set an individual arp entry 2651553Srgrimes */ 26613977Sphkint 26713977Sphkset(int argc, char **argv) 2681553Srgrimes{ 2691553Srgrimes struct hostent *hp; 27087598Smikeh register struct sockaddr_inarp *addr = &sin_m; 2711553Srgrimes register struct sockaddr_dl *sdl; 2721553Srgrimes register struct rt_msghdr *rtm = &(m_rtmsg.m_rtm); 27393952Sru struct ether_addr *ea; 2741553Srgrimes char *host = argv[0], *eaddr = argv[1]; 2751553Srgrimes 2761553Srgrimes getsocket(); 2771553Srgrimes argc -= 2; 2781553Srgrimes argv += 2; 2791553Srgrimes sdl_m = blank_sdl; 2801553Srgrimes sin_m = blank_sin; 28187598Smikeh addr->sin_addr.s_addr = inet_addr(host); 28287598Smikeh if (addr->sin_addr.s_addr == INADDR_NONE) { 2831553Srgrimes if (!(hp = gethostbyname(host))) { 28429060Scharnier warnx("%s: %s", host, hstrerror(h_errno)); 2851553Srgrimes return (1); 2861553Srgrimes } 28787598Smikeh bcopy((char *)hp->h_addr, (char *)&addr->sin_addr, 28887598Smikeh sizeof addr->sin_addr); 2891553Srgrimes } 29077870Sru doing_proxy = flags = proxy_only = expire_time = 0; 2911553Srgrimes while (argc-- > 0) { 2921553Srgrimes if (strncmp(argv[0], "temp", 4) == 0) { 29377870Sru struct timeval tv; 29477870Sru gettimeofday(&tv, 0); 29577870Sru expire_time = tv.tv_sec + 20 * 60; 2961553Srgrimes } 2971553Srgrimes else if (strncmp(argv[0], "pub", 3) == 0) { 2981553Srgrimes flags |= RTF_ANNOUNCE; 29977870Sru doing_proxy = 1; 30077870Sru if (argc && strncmp(argv[1], "only", 3) == 0) { 30177870Sru proxy_only = 1; 30277870Sru sin_m.sin_other = SIN_PROXY; 30377870Sru argc--; argv++; 30477870Sru } 3051553Srgrimes } else if (strncmp(argv[0], "trail", 5) == 0) { 3061553Srgrimes printf("%s: Sending trailers is no longer supported\n", 3071553Srgrimes host); 3081553Srgrimes } 3091553Srgrimes argv++; 3101553Srgrimes } 31193952Sru ea = (struct ether_addr *)LLADDR(&sdl_m); 31213977Sphk if (doing_proxy && !strcmp(eaddr, "auto")) { 31387598Smikeh if (!get_ether_addr(addr->sin_addr.s_addr, ea)) { 31473135Sru printf("no interface found for %s\n", 31587598Smikeh inet_ntoa(addr->sin_addr)); 31613977Sphk return (1); 31713977Sphk } 31893952Sru sdl_m.sdl_alen = ETHER_ADDR_LEN; 31913977Sphk } else { 32020690Snate if (my_ether_aton(eaddr, ea) == 0) 32193952Sru sdl_m.sdl_alen = ETHER_ADDR_LEN; 32213977Sphk } 3231553Srgrimestryagain: 3241553Srgrimes if (rtmsg(RTM_GET) < 0) { 32529060Scharnier warn("%s", host); 3261553Srgrimes return (1); 3271553Srgrimes } 32887598Smikeh addr = (struct sockaddr_inarp *)(rtm + 1); 32987598Smikeh sdl = (struct sockaddr_dl *)(ROUNDUP(addr->sin_len) + (char *)addr); 33087598Smikeh if (addr->sin_addr.s_addr == sin_m.sin_addr.s_addr) { 3311553Srgrimes if (sdl->sdl_family == AF_LINK && 3321553Srgrimes (rtm->rtm_flags & RTF_LLINFO) && 3331553Srgrimes !(rtm->rtm_flags & RTF_GATEWAY)) switch (sdl->sdl_type) { 3341553Srgrimes case IFT_ETHER: case IFT_FDDI: case IFT_ISO88023: 33575180Syar case IFT_ISO88024: case IFT_ISO88025: case IFT_L2VLAN: 3361553Srgrimes goto overwrite; 3371553Srgrimes } 3381553Srgrimes if (doing_proxy == 0) { 3391553Srgrimes printf("set: can only proxy for %s\n", host); 3401553Srgrimes return (1); 3411553Srgrimes } 3421553Srgrimes if (sin_m.sin_other & SIN_PROXY) { 3431553Srgrimes printf("set: proxy entry exists for non 802 device\n"); 3441553Srgrimes return(1); 3451553Srgrimes } 3461553Srgrimes sin_m.sin_other = SIN_PROXY; 34777870Sru proxy_only = 1; 3481553Srgrimes goto tryagain; 3491553Srgrimes } 3501553Srgrimesoverwrite: 3511553Srgrimes if (sdl->sdl_family != AF_LINK) { 3521553Srgrimes printf("cannot intuit interface index and type for %s\n", host); 3531553Srgrimes return (1); 3541553Srgrimes } 3551553Srgrimes sdl_m.sdl_type = sdl->sdl_type; 3561553Srgrimes sdl_m.sdl_index = sdl->sdl_index; 3571553Srgrimes return (rtmsg(RTM_ADD)); 3581553Srgrimes} 3591553Srgrimes 3601553Srgrimes/* 3611553Srgrimes * Display an individual arp entry 3621553Srgrimes */ 36331145Sjulianint 36413977Sphkget(char *host) 3651553Srgrimes{ 3661553Srgrimes struct hostent *hp; 36787598Smikeh struct sockaddr_inarp *addr = &sin_m; 3681553Srgrimes 3691553Srgrimes sin_m = blank_sin; 37087598Smikeh addr->sin_addr.s_addr = inet_addr(host); 37187598Smikeh if (addr->sin_addr.s_addr == INADDR_NONE) { 37229060Scharnier if (!(hp = gethostbyname(host))) 37329060Scharnier errx(1, "%s: %s", host, hstrerror(h_errno)); 37487598Smikeh bcopy((char *)hp->h_addr, (char *)&addr->sin_addr, 37587598Smikeh sizeof addr->sin_addr); 3761553Srgrimes } 37787598Smikeh search(addr->sin_addr.s_addr, print_entry); 3781553Srgrimes if (found_entry == 0) { 3791553Srgrimes printf("%s (%s) -- no entry\n", 38087598Smikeh host, inet_ntoa(addr->sin_addr)); 38131145Sjulian return(1); 3821553Srgrimes } 38331145Sjulian return(0); 3841553Srgrimes} 3851553Srgrimes 3861553Srgrimes/* 3878857Srgrimes * Delete an arp entry 3881553Srgrimes */ 38913977Sphkint 39013977Sphkdelete(char *host, char *info) 3911553Srgrimes{ 3921553Srgrimes struct hostent *hp; 39387598Smikeh register struct sockaddr_inarp *addr = &sin_m; 3941553Srgrimes register struct rt_msghdr *rtm = &m_rtmsg.m_rtm; 3951553Srgrimes struct sockaddr_dl *sdl; 3961553Srgrimes 3971553Srgrimes getsocket(); 3981553Srgrimes sin_m = blank_sin; 39977870Sru if (info) { 40077870Sru if (strncmp(info, "pub", 3) == 0) 40177870Sru sin_m.sin_other = SIN_PROXY; 40277870Sru else 40377870Sru usage(); 40477870Sru } 40587598Smikeh addr->sin_addr.s_addr = inet_addr(host); 40687598Smikeh if (addr->sin_addr.s_addr == INADDR_NONE) { 4071553Srgrimes if (!(hp = gethostbyname(host))) { 40829060Scharnier warnx("%s: %s", host, hstrerror(h_errno)); 4091553Srgrimes return (1); 4101553Srgrimes } 41187598Smikeh bcopy((char *)hp->h_addr, (char *)&addr->sin_addr, 41287598Smikeh sizeof addr->sin_addr); 4131553Srgrimes } 4141553Srgrimestryagain: 4151553Srgrimes if (rtmsg(RTM_GET) < 0) { 41629060Scharnier warn("%s", host); 4171553Srgrimes return (1); 4181553Srgrimes } 41987598Smikeh addr = (struct sockaddr_inarp *)(rtm + 1); 42087598Smikeh sdl = (struct sockaddr_dl *)(ROUNDUP(addr->sin_len) + (char *)addr); 42187598Smikeh if (addr->sin_addr.s_addr == sin_m.sin_addr.s_addr) { 4221553Srgrimes if (sdl->sdl_family == AF_LINK && 4231553Srgrimes (rtm->rtm_flags & RTF_LLINFO) && 4241553Srgrimes !(rtm->rtm_flags & RTF_GATEWAY)) switch (sdl->sdl_type) { 4251553Srgrimes case IFT_ETHER: case IFT_FDDI: case IFT_ISO88023: 42675180Syar case IFT_ISO88024: case IFT_ISO88025: case IFT_L2VLAN: 4271553Srgrimes goto delete; 4281553Srgrimes } 4291553Srgrimes } 4301553Srgrimes if (sin_m.sin_other & SIN_PROXY) { 4311553Srgrimes fprintf(stderr, "delete: can't locate %s\n",host); 4321553Srgrimes return (1); 4331553Srgrimes } else { 4341553Srgrimes sin_m.sin_other = SIN_PROXY; 4351553Srgrimes goto tryagain; 4361553Srgrimes } 4371553Srgrimesdelete: 4381553Srgrimes if (sdl->sdl_family != AF_LINK) { 4391553Srgrimes printf("cannot locate %s\n", host); 4401553Srgrimes return (1); 4411553Srgrimes } 44213977Sphk if (rtmsg(RTM_DELETE) == 0) { 44387598Smikeh printf("%s (%s) deleted\n", host, inet_ntoa(addr->sin_addr)); 44413977Sphk return (0); 44513977Sphk } 44613977Sphk return (1); 4471553Srgrimes} 4481553Srgrimes 4491553Srgrimes/* 45031145Sjulian * Search the arp table and do some action on matching entries 4511553Srgrimes */ 45213977Sphkvoid 45331145Sjuliansearch(u_long addr, void (*action)(struct sockaddr_dl *sdl, 45431145Sjulian struct sockaddr_inarp *sin, struct rt_msghdr *rtm)) 4551553Srgrimes{ 4561553Srgrimes int mib[6]; 4571553Srgrimes size_t needed; 45831145Sjulian char *lim, *buf, *next; 4591553Srgrimes struct rt_msghdr *rtm; 46087598Smikeh struct sockaddr_inarp *sin2; 4611553Srgrimes struct sockaddr_dl *sdl; 4621553Srgrimes 4631553Srgrimes mib[0] = CTL_NET; 4641553Srgrimes mib[1] = PF_ROUTE; 4651553Srgrimes mib[2] = 0; 4661553Srgrimes mib[3] = AF_INET; 4671553Srgrimes mib[4] = NET_RT_FLAGS; 4681553Srgrimes mib[5] = RTF_LLINFO; 4691553Srgrimes if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0) 47029060Scharnier errx(1, "route-sysctl-estimate"); 4711553Srgrimes if ((buf = malloc(needed)) == NULL) 47229060Scharnier errx(1, "malloc"); 4731553Srgrimes if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0) 47429060Scharnier errx(1, "actual retrieval of routing table"); 4751553Srgrimes lim = buf + needed; 4761553Srgrimes for (next = buf; next < lim; next += rtm->rtm_msglen) { 4771553Srgrimes rtm = (struct rt_msghdr *)next; 47887598Smikeh sin2 = (struct sockaddr_inarp *)(rtm + 1); 47987598Smikeh (char *)sdl = (char *)sin2 + ROUNDUP(sin2->sin_len); 4801553Srgrimes if (addr) { 48187598Smikeh if (addr != sin2->sin_addr.s_addr) 4821553Srgrimes continue; 4831553Srgrimes found_entry = 1; 4841553Srgrimes } 48587598Smikeh (*action)(sdl, sin2, rtm); 4861553Srgrimes } 48776216Syar free(buf); 4881553Srgrimes} 4891553Srgrimes 49031145Sjulian/* 49131145Sjulian * Display an arp entry 49231145Sjulian */ 49313977Sphkvoid 49431145Sjulianprint_entry(struct sockaddr_dl *sdl, 49587598Smikeh struct sockaddr_inarp *addr, struct rt_msghdr *rtm) 49631145Sjulian{ 49777870Sru const char *host; 49831145Sjulian struct hostent *hp; 49996202Skbyanc struct iso88025_sockaddr_dl_data *trld; 50084666Sru char ifname[IF_NAMESIZE]; 50144627Sjulian int seg; 50231145Sjulian 50331145Sjulian if (nflag == 0) 50487598Smikeh hp = gethostbyaddr((caddr_t)&(addr->sin_addr), 50587598Smikeh sizeof addr->sin_addr, AF_INET); 50631145Sjulian else 50731145Sjulian hp = 0; 50831145Sjulian if (hp) 50931145Sjulian host = hp->h_name; 51031145Sjulian else { 51131145Sjulian host = "?"; 51231145Sjulian if (h_errno == TRY_AGAIN) 51331145Sjulian nflag = 1; 51431145Sjulian } 51587598Smikeh printf("%s (%s) at ", host, inet_ntoa(addr->sin_addr)); 51631145Sjulian if (sdl->sdl_alen) 51793952Sru printf("%s", ether_ntoa((struct ether_addr *)LLADDR(sdl))); 51831145Sjulian else 51931145Sjulian printf("(incomplete)"); 52084666Sru if (if_indextoname(sdl->sdl_index, ifname) != NULL) 52184666Sru printf(" on %s", ifname); 52231145Sjulian if (rtm->rtm_rmx.rmx_expire == 0) 52331145Sjulian printf(" permanent"); 52487598Smikeh if (addr->sin_other & SIN_PROXY) 52531145Sjulian printf(" published (proxy only)"); 52631145Sjulian if (rtm->rtm_addrs & RTA_NETMASK) { 52787598Smikeh addr = (struct sockaddr_inarp *) 52851250Sru (ROUNDUP(sdl->sdl_len) + (char *)sdl); 52987598Smikeh if (addr->sin_addr.s_addr == 0xffffffff) 53031145Sjulian printf(" published"); 53187598Smikeh if (addr->sin_len != 8) 53251250Sru printf("(weird)"); 53331145Sjulian } 53444627Sjulian switch(sdl->sdl_type) { 53544627Sjulian case IFT_ETHER: 53644627Sjulian printf(" [ethernet]"); 53744627Sjulian break; 53844627Sjulian case IFT_ISO88025: 53944627Sjulian printf(" [token-ring]"); 54096202Skbyanc trld = SDL_ISO88025(sdl); 54196202Skbyanc if (trld->trld_rcf != 0) { 54296202Skbyanc printf(" rt=%x", ntohs(trld->trld_rcf)); 54396202Skbyanc for (seg = 0; 54496202Skbyanc seg < ((TR_RCF_RIFLEN(trld->trld_rcf) - 2 ) / 2); 54596202Skbyanc seg++) 54696235Swpaul printf(":%x", ntohs(*(trld->trld_route[seg]))); 54796202Skbyanc } 54844627Sjulian break; 54985123Smdodd case IFT_FDDI: 55085123Smdodd printf(" [fddi]"); 55185123Smdodd break; 55285123Smdodd case IFT_ATM: 55385123Smdodd printf(" [atm]"); 55485123Smdodd break; 55575180Syar case IFT_L2VLAN: 55675180Syar printf(" [vlan]"); 55775180Syar break; 55844627Sjulian default: 55994075Smurray break; 56044627Sjulian } 56144627Sjulian 56231145Sjulian printf("\n"); 56344627Sjulian 56431145Sjulian} 56531145Sjulian 56631145Sjulian/* 56731145Sjulian * Nuke an arp entry 56831145Sjulian */ 56931145Sjulianvoid 57087598Smikehnuke_entry(struct sockaddr_dl *sdl __unused, 57187598Smikeh struct sockaddr_inarp *addr, struct rt_msghdr *rtm __unused) 57231145Sjulian{ 57331145Sjulian char ip[20]; 57431145Sjulian 57587598Smikeh snprintf(ip, sizeof(ip), "%s", inet_ntoa(addr->sin_addr)); 57631145Sjulian delete(ip, NULL); 57731145Sjulian} 57831145Sjulian 57913977Sphkint 58093952Srumy_ether_aton(char *a, struct ether_addr *n) 5811553Srgrimes{ 58293952Sru struct ether_addr *ea; 5831553Srgrimes 58493952Sru if ((ea = ether_aton(a)) == NULL) { 58529060Scharnier warnx("invalid Ethernet address '%s'", a); 5861553Srgrimes return (1); 5871553Srgrimes } 58893952Sru *n = *ea; 5891553Srgrimes return (0); 5901553Srgrimes} 5911553Srgrimes 59213977Sphkvoid 59313977Sphkusage(void) 5941553Srgrimes{ 59531145Sjulian fprintf(stderr, "%s\n%s\n%s\n%s\n%s\n%s\n%s\n", 59629060Scharnier "usage: arp [-n] hostname", 59731145Sjulian " arp [-n] -a", 59877870Sru " arp -d hostname [pub]", 59931145Sjulian " arp -d -a", 60029060Scharnier " arp -s hostname ether_addr [temp] [pub]", 60129060Scharnier " arp -S hostname ether_addr [temp] [pub]", 60229060Scharnier " arp -f filename"); 6031553Srgrimes exit(1); 6041553Srgrimes} 6051553Srgrimes 60613977Sphkint 60713977Sphkrtmsg(int cmd) 6081553Srgrimes{ 6091553Srgrimes static int seq; 6101553Srgrimes int rlen; 6111553Srgrimes register struct rt_msghdr *rtm = &m_rtmsg.m_rtm; 6121553Srgrimes register char *cp = m_rtmsg.m_space; 6131553Srgrimes register int l; 6141553Srgrimes 6151553Srgrimes errno = 0; 6161553Srgrimes if (cmd == RTM_DELETE) 6171553Srgrimes goto doit; 6181553Srgrimes bzero((char *)&m_rtmsg, sizeof(m_rtmsg)); 6191553Srgrimes rtm->rtm_flags = flags; 6201553Srgrimes rtm->rtm_version = RTM_VERSION; 6211553Srgrimes 6221553Srgrimes switch (cmd) { 6231553Srgrimes default: 62429060Scharnier errx(1, "internal wrong cmd"); 6251553Srgrimes case RTM_ADD: 6261553Srgrimes rtm->rtm_addrs |= RTA_GATEWAY; 6271553Srgrimes rtm->rtm_rmx.rmx_expire = expire_time; 6281553Srgrimes rtm->rtm_inits = RTV_EXPIRE; 6291553Srgrimes rtm->rtm_flags |= (RTF_HOST | RTF_STATIC); 6301553Srgrimes sin_m.sin_other = 0; 6311553Srgrimes if (doing_proxy) { 63277870Sru if (proxy_only) 6331553Srgrimes sin_m.sin_other = SIN_PROXY; 6341553Srgrimes else { 6351553Srgrimes rtm->rtm_addrs |= RTA_NETMASK; 6361553Srgrimes rtm->rtm_flags &= ~RTF_HOST; 6371553Srgrimes } 6381553Srgrimes } 6391553Srgrimes /* FALLTHROUGH */ 6401553Srgrimes case RTM_GET: 6411553Srgrimes rtm->rtm_addrs |= RTA_DST; 6421553Srgrimes } 6431553Srgrimes#define NEXTADDR(w, s) \ 6441553Srgrimes if (rtm->rtm_addrs & (w)) { \ 64551250Sru bcopy((char *)&s, cp, sizeof(s)); cp += ROUNDUP(sizeof(s));} 6461553Srgrimes 6471553Srgrimes NEXTADDR(RTA_DST, sin_m); 6481553Srgrimes NEXTADDR(RTA_GATEWAY, sdl_m); 6491553Srgrimes NEXTADDR(RTA_NETMASK, so_mask); 6501553Srgrimes 6511553Srgrimes rtm->rtm_msglen = cp - (char *)&m_rtmsg; 6521553Srgrimesdoit: 6531553Srgrimes l = rtm->rtm_msglen; 6541553Srgrimes rtm->rtm_seq = ++seq; 6551553Srgrimes rtm->rtm_type = cmd; 6561553Srgrimes if ((rlen = write(s, (char *)&m_rtmsg, l)) < 0) { 6571553Srgrimes if (errno != ESRCH || cmd != RTM_DELETE) { 65829060Scharnier warn("writing to routing socket"); 6591553Srgrimes return (-1); 6601553Srgrimes } 6611553Srgrimes } 6621553Srgrimes do { 6631553Srgrimes l = read(s, (char *)&m_rtmsg, sizeof(m_rtmsg)); 6641553Srgrimes } while (l > 0 && (rtm->rtm_seq != seq || rtm->rtm_pid != pid)); 6651553Srgrimes if (l < 0) 66629060Scharnier warn("read from routing socket"); 6671553Srgrimes return (0); 6681553Srgrimes} 6691553Srgrimes 67013977Sphk/* 67113977Sphk * get_ether_addr - get the hardware address of an interface on the 67213977Sphk * the same subnet as ipaddr. 67313977Sphk */ 67413977Sphk#define MAX_IFS 32 67513977Sphk 67613977Sphkint 67793952Sruget_ether_addr(u_int32_t ipaddr, struct ether_addr *hwaddr) 67813977Sphk{ 67913977Sphk struct ifreq *ifr, *ifend, *ifp; 68057727Sshin u_int32_t ina, mask; 68113977Sphk struct sockaddr_dl *dla; 68213977Sphk struct ifreq ifreq; 68313977Sphk struct ifconf ifc; 68413977Sphk struct ifreq ifs[MAX_IFS]; 68587598Smikeh int sock; 68613977Sphk 68787598Smikeh sock = socket(AF_INET, SOCK_DGRAM, 0); 68887598Smikeh if (sock < 0) 68929060Scharnier err(1, "socket"); 69013977Sphk 69113977Sphk ifc.ifc_len = sizeof(ifs); 69213977Sphk ifc.ifc_req = ifs; 69392735Smikeh if (ioctl(sock, SIOCGIFCONF, &ifc) < 0) { 69429060Scharnier warnx("ioctl(SIOCGIFCONF)"); 69587598Smikeh close(sock); 69613977Sphk return 0; 69713977Sphk } 69813977Sphk 69913977Sphk /* 70013977Sphk * Scan through looking for an interface with an Internet 70113977Sphk * address on the same subnet as `ipaddr'. 70213977Sphk */ 70313977Sphk ifend = (struct ifreq *) (ifc.ifc_buf + ifc.ifc_len); 70413977Sphk for (ifr = ifc.ifc_req; ifr < ifend; ) { 70513977Sphk if (ifr->ifr_addr.sa_family == AF_INET) { 70613977Sphk ina = ((struct sockaddr_in *) 70713977Sphk &ifr->ifr_addr)->sin_addr.s_addr; 70813977Sphk strncpy(ifreq.ifr_name, ifr->ifr_name, 70913977Sphk sizeof(ifreq.ifr_name)); 71013977Sphk /* 71113977Sphk * Check that the interface is up, 71213977Sphk * and not point-to-point or loopback. 71313977Sphk */ 71492735Smikeh if (ioctl(sock, SIOCGIFFLAGS, &ifreq) < 0) 71513977Sphk continue; 71613977Sphk if ((ifreq.ifr_flags & 71713977Sphk (IFF_UP|IFF_BROADCAST|IFF_POINTOPOINT| 71813977Sphk IFF_LOOPBACK|IFF_NOARP)) 71913977Sphk != (IFF_UP|IFF_BROADCAST)) 72013977Sphk goto nextif; 72113977Sphk /* 72213977Sphk * Get its netmask and check that it's on 72313977Sphk * the right subnet. 72413977Sphk */ 72592735Smikeh if (ioctl(sock, SIOCGIFNETMASK, &ifreq) < 0) 72613977Sphk continue; 72713977Sphk mask = ((struct sockaddr_in *) 72813977Sphk &ifreq.ifr_addr)->sin_addr.s_addr; 72913977Sphk if ((ipaddr & mask) != (ina & mask)) 73013977Sphk goto nextif; 73113977Sphk break; 73213977Sphk } 73313977Sphknextif: 73447753Sarchie ifr = (struct ifreq *) ((char *)&ifr->ifr_addr 73547753Sarchie + MAX(ifr->ifr_addr.sa_len, sizeof(ifr->ifr_addr))); 73613977Sphk } 73713977Sphk 73813977Sphk if (ifr >= ifend) { 73987598Smikeh close(sock); 74013977Sphk return 0; 74113977Sphk } 74213977Sphk 74313977Sphk /* 74413977Sphk * Now scan through again looking for a link-level address 74513977Sphk * for this interface. 74613977Sphk */ 74713977Sphk ifp = ifr; 74813977Sphk for (ifr = ifc.ifc_req; ifr < ifend; ) { 74913977Sphk if (strcmp(ifp->ifr_name, ifr->ifr_name) == 0 75013977Sphk && ifr->ifr_addr.sa_family == AF_LINK) { 75113977Sphk /* 75213977Sphk * Found the link-level address - copy it out 75313977Sphk */ 75413977Sphk dla = (struct sockaddr_dl *) &ifr->ifr_addr; 75513977Sphk memcpy(hwaddr, LLADDR(dla), dla->sdl_alen); 75692735Smikeh close (sock); 75713977Sphk printf("using interface %s for proxy with address ", 75813977Sphk ifp->ifr_name); 75993952Sru printf("%s\n", ether_ntoa(hwaddr)); 76013977Sphk return dla->sdl_alen; 76113977Sphk } 76247753Sarchie ifr = (struct ifreq *) ((char *)&ifr->ifr_addr 76347753Sarchie + MAX(ifr->ifr_addr.sa_len, sizeof(ifr->ifr_addr))); 76413977Sphk } 76513977Sphk return 0; 76613977Sphk} 767