arp.c revision 177362
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 * 4. Neither the name of the University nor the names of its contributors 171553Srgrimes * may be used to endorse or promote products derived from this software 181553Srgrimes * without specific prior written permission. 191553Srgrimes * 201553Srgrimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 211553Srgrimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 221553Srgrimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 231553Srgrimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 241553Srgrimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 251553Srgrimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 261553Srgrimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 271553Srgrimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 281553Srgrimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 291553Srgrimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 301553Srgrimes * SUCH DAMAGE. 311553Srgrimes */ 321553Srgrimes 33114601Sobrien#if 0 341553Srgrimes#ifndef lint 3513977Sphkstatic char const copyright[] = 361553Srgrimes"@(#) Copyright (c) 1984, 1993\n\ 371553Srgrimes The Regents of the University of California. All rights reserved.\n"; 381553Srgrimes#endif /* not lint */ 391553Srgrimes 401553Srgrimes#ifndef lint 4113977Sphkstatic char const sccsid[] = "@(#)from: arp.c 8.2 (Berkeley) 1/2/94"; 42114601Sobrien#endif /* not lint */ 4329060Scharnier#endif 44114601Sobrien#include <sys/cdefs.h> 45114601Sobrien__FBSDID("$FreeBSD: head/usr.sbin/arp/arp.c 177362 2008-03-18 21:45:27Z sam $"); 461553Srgrimes 471553Srgrimes/* 481553Srgrimes * arp - display, set, and delete arp table entries 491553Srgrimes */ 501553Srgrimes 511553Srgrimes 521553Srgrimes#include <sys/param.h> 531553Srgrimes#include <sys/file.h> 541553Srgrimes#include <sys/socket.h> 5513977Sphk#include <sys/sockio.h> 561553Srgrimes#include <sys/sysctl.h> 5713977Sphk#include <sys/ioctl.h> 5820287Swollman#include <sys/time.h> 591553Srgrimes 601553Srgrimes#include <net/if.h> 611553Srgrimes#include <net/if_dl.h> 621553Srgrimes#include <net/if_types.h> 6396235Swpaul#include <net/route.h> 6496202Skbyanc#include <net/iso88025.h> 651553Srgrimes 661553Srgrimes#include <netinet/in.h> 671553Srgrimes#include <netinet/if_ether.h> 681553Srgrimes 691553Srgrimes#include <arpa/inet.h> 701553Srgrimes 71108314Sru#include <ctype.h> 7229060Scharnier#include <err.h> 7329060Scharnier#include <errno.h> 741553Srgrimes#include <netdb.h> 751553Srgrimes#include <nlist.h> 7629060Scharnier#include <paths.h> 771553Srgrimes#include <stdio.h> 7813977Sphk#include <stdlib.h> 7993590Smike#include <string.h> 8029060Scharnier#include <strings.h> 8113977Sphk#include <unistd.h> 821553Srgrimes 83128181Sluigitypedef void (action_fn)(struct sockaddr_dl *sdl, 84128192Sluigi struct sockaddr_inarp *s_in, struct rt_msghdr *rtm); 8513977Sphk 86128181Sluigistatic int search(u_long addr, action_fn *action); 87128181Sluigistatic action_fn print_entry; 88128181Sluigistatic action_fn nuke_entry; 89128181Sluigi 90128192Sluigistatic int delete(char *host, int do_proxy); 91128181Sluigistatic void usage(void); 92128181Sluigistatic int set(int argc, char **argv); 93147172Srustatic int get(char *host); 94128181Sluigistatic int file(char *name); 95128192Sluigistatic struct rt_msghdr *rtmsg(int cmd, 96147172Sru struct sockaddr_inarp *dst, struct sockaddr_dl *sdl); 97147172Srustatic int get_ether_addr(in_addr_t ipaddr, struct ether_addr *hwaddr); 98147172Srustatic struct sockaddr_inarp *getaddr(char *host); 99147172Srustatic int valid_type(int type); 100128181Sluigi 10131145Sjulianstatic int nflag; /* no reverse dns lookups */ 102117729Syarstatic char *rifname; 1031553Srgrimes 104128181Sluigistatic int expire_time, flags, doing_proxy, proxy_only; 105128192Sluigi 10631145Sjulian/* which function we're supposed to do */ 10731145Sjulian#define F_GET 1 10831145Sjulian#define F_SET 2 10931145Sjulian#define F_FILESET 3 11031145Sjulian#define F_REPLACE 4 11131145Sjulian#define F_DELETE 5 11231145Sjulian 11331145Sjulian#define SETFUNC(f) { if (func) usage(); func = (f); } 11431145Sjulian 11513977Sphkint 11677870Srumain(int argc, char *argv[]) 1171553Srgrimes{ 11831145Sjulian int ch, func = 0; 11931145Sjulian int rtn = 0; 120128181Sluigi int aflag = 0; /* do it for all entries */ 1211553Srgrimes 122117729Syar while ((ch = getopt(argc, argv, "andfsSi:")) != -1) 1231553Srgrimes switch((char)ch) { 1241553Srgrimes case 'a': 12531145Sjulian aflag = 1; 12631145Sjulian break; 1271553Srgrimes case 'd': 12831145Sjulian SETFUNC(F_DELETE); 12931145Sjulian break; 1301553Srgrimes case 'n': 1311553Srgrimes nflag = 1; 13231145Sjulian break; 13313977Sphk case 'S': 13431145Sjulian SETFUNC(F_REPLACE); 13531145Sjulian break; 1361553Srgrimes case 's': 13731145Sjulian SETFUNC(F_SET); 13831145Sjulian break; 1399874Sjkh case 'f' : 14031145Sjulian SETFUNC(F_FILESET); 14131145Sjulian break; 142117729Syar case 'i': 143117729Syar rifname = optarg; 144117729Syar break; 1451553Srgrimes case '?': 1461553Srgrimes default: 1471553Srgrimes usage(); 1481553Srgrimes } 14931145Sjulian argc -= optind; 15031145Sjulian argv += optind; 15131145Sjulian 15231145Sjulian if (!func) 15331145Sjulian func = F_GET; 154117729Syar if (rifname) { 155154162Sbrooks if (func != F_GET && !(func == F_DELETE && aflag)) 156117729Syar errx(1, "-i not applicable to this operation"); 157117729Syar if (if_nametoindex(rifname) == 0) { 158117729Syar if (errno == ENXIO) 159117729Syar errx(1, "interface %s does not exist", rifname); 160117729Syar else 161117729Syar err(1, "if_nametoindex(%s)", rifname); 162117729Syar } 163117729Syar } 16431145Sjulian switch (func) { 16531145Sjulian case F_GET: 16631145Sjulian if (aflag) { 16731145Sjulian if (argc != 0) 16831145Sjulian usage(); 16931145Sjulian search(0, print_entry); 17031145Sjulian } else { 17131145Sjulian if (argc != 1) 17231145Sjulian usage(); 173147172Sru rtn = get(argv[0]); 17431145Sjulian } 17531145Sjulian break; 17631145Sjulian case F_SET: 17731145Sjulian case F_REPLACE: 17877870Sru if (argc < 2 || argc > 6) 17931145Sjulian usage(); 18031145Sjulian if (func == F_REPLACE) 181147172Sru (void)delete(argv[0], 0); 18231145Sjulian rtn = set(argc, argv) ? 1 : 0; 18331145Sjulian break; 18431145Sjulian case F_DELETE: 18531145Sjulian if (aflag) { 18631145Sjulian if (argc != 0) 18731145Sjulian usage(); 18831145Sjulian search(0, nuke_entry); 18931145Sjulian } else { 190128192Sluigi if (argc == 2 && strncmp(argv[1], "pub", 3) == 0) 191128192Sluigi ch = SIN_PROXY; 192128192Sluigi else if (argc == 1) 193128192Sluigi ch = 0; 194128192Sluigi else 19531145Sjulian usage(); 196128192Sluigi rtn = delete(argv[0], ch); 19731145Sjulian } 19831145Sjulian break; 19931145Sjulian case F_FILESET: 20031145Sjulian if (argc != 1) 20131145Sjulian usage(); 20231145Sjulian rtn = file(argv[0]); 20331145Sjulian break; 20431145Sjulian } 20531145Sjulian 206147172Sru return (rtn); 2071553Srgrimes} 2081553Srgrimes 2091553Srgrimes/* 2101553Srgrimes * Process a file to set standard arp entries 2111553Srgrimes */ 212128181Sluigistatic int 21313977Sphkfile(char *name) 2141553Srgrimes{ 2151553Srgrimes FILE *fp; 2161553Srgrimes int i, retval; 217109413Sru char line[100], arg[5][50], *args[5], *p; 2181553Srgrimes 21929060Scharnier if ((fp = fopen(name, "r")) == NULL) 220128054Smux err(1, "cannot open %s", name); 2211553Srgrimes args[0] = &arg[0][0]; 2221553Srgrimes args[1] = &arg[1][0]; 2231553Srgrimes args[2] = &arg[2][0]; 2241553Srgrimes args[3] = &arg[3][0]; 2251553Srgrimes args[4] = &arg[4][0]; 2261553Srgrimes retval = 0; 227167260Skevlo while(fgets(line, sizeof(line), fp) != NULL) { 228109413Sru if ((p = strchr(line, '#')) != NULL) 229109413Sru *p = '\0'; 230109413Sru for (p = line; isblank(*p); p++); 231111910Sru if (*p == '\n' || *p == '\0') 232108314Sru continue; 233109413Sru i = sscanf(p, "%49s %49s %49s %49s %49s", arg[0], arg[1], 23456134Sjkh arg[2], arg[3], arg[4]); 2351553Srgrimes if (i < 2) { 23629060Scharnier warnx("bad line: %s", line); 2371553Srgrimes retval = 1; 2381553Srgrimes continue; 2391553Srgrimes } 2401553Srgrimes if (set(i, args)) 2411553Srgrimes retval = 1; 2421553Srgrimes } 2431553Srgrimes fclose(fp); 2441553Srgrimes return (retval); 2451553Srgrimes} 2461553Srgrimes 2471553Srgrimes/* 248128192Sluigi * Given a hostname, fills up a (static) struct sockaddr_inarp with 249128192Sluigi * the address of the host and returns a pointer to the 250128192Sluigi * structure. 251128192Sluigi */ 252128192Sluigistatic struct sockaddr_inarp * 253128192Sluigigetaddr(char *host) 254128192Sluigi{ 255128192Sluigi struct hostent *hp; 256128192Sluigi static struct sockaddr_inarp reply; 257128192Sluigi 258128192Sluigi bzero(&reply, sizeof(reply)); 259128192Sluigi reply.sin_len = sizeof(reply); 260128192Sluigi reply.sin_family = AF_INET; 261128192Sluigi reply.sin_addr.s_addr = inet_addr(host); 262128192Sluigi if (reply.sin_addr.s_addr == INADDR_NONE) { 263128192Sluigi if (!(hp = gethostbyname(host))) { 264128192Sluigi warnx("%s: %s", host, hstrerror(h_errno)); 265147172Sru return (NULL); 266128192Sluigi } 267128192Sluigi bcopy((char *)hp->h_addr, (char *)&reply.sin_addr, 268128192Sluigi sizeof reply.sin_addr); 269128192Sluigi } 270147172Sru return (&reply); 271128192Sluigi} 272128192Sluigi 273128192Sluigi/* 274147172Sru * Returns true if the type is a valid one for ARP. 275128192Sluigi */ 276128192Sluigistatic int 277128192Sluigivalid_type(int type) 278128192Sluigi{ 279147172Sru 280128192Sluigi switch (type) { 281128192Sluigi case IFT_ETHER: 282128192Sluigi case IFT_FDDI: 283128192Sluigi case IFT_ISO88023: 284128192Sluigi case IFT_ISO88024: 285128192Sluigi case IFT_ISO88025: 286128192Sluigi case IFT_L2VLAN: 287151989Sthompsa case IFT_BRIDGE: 288147172Sru return (1); 289147172Sru default: 290147172Sru return (0); 291128192Sluigi } 292128192Sluigi} 293128192Sluigi 294128192Sluigi/* 2958857Srgrimes * Set an individual arp entry 2961553Srgrimes */ 297128192Sluigistatic int 29813977Sphkset(int argc, char **argv) 2991553Srgrimes{ 300128192Sluigi struct sockaddr_inarp *addr; 301128192Sluigi struct sockaddr_inarp *dst; /* what are we looking for */ 302128054Smux struct sockaddr_dl *sdl; 303128181Sluigi struct rt_msghdr *rtm; 30493952Sru struct ether_addr *ea; 3051553Srgrimes char *host = argv[0], *eaddr = argv[1]; 306147172Sru struct sockaddr_dl sdl_m; 3071553Srgrimes 3081553Srgrimes argc -= 2; 3091553Srgrimes argv += 2; 310128181Sluigi 311128181Sluigi bzero(&sdl_m, sizeof(sdl_m)); 312128181Sluigi sdl_m.sdl_len = sizeof(sdl_m); 313128181Sluigi sdl_m.sdl_family = AF_LINK; 314128181Sluigi 315128192Sluigi dst = getaddr(host); 316128192Sluigi if (dst == NULL) 317128192Sluigi return (1); 31877870Sru doing_proxy = flags = proxy_only = expire_time = 0; 3191553Srgrimes while (argc-- > 0) { 3201553Srgrimes if (strncmp(argv[0], "temp", 4) == 0) { 32177870Sru struct timeval tv; 32277870Sru gettimeofday(&tv, 0); 32377870Sru expire_time = tv.tv_sec + 20 * 60; 324177362Ssam } else if (strncmp(argv[0], "pub", 3) == 0) { 3251553Srgrimes flags |= RTF_ANNOUNCE; 32677870Sru doing_proxy = 1; 32777870Sru if (argc && strncmp(argv[1], "only", 3) == 0) { 32877870Sru proxy_only = 1; 329128192Sluigi dst->sin_other = SIN_PROXY; 33077870Sru argc--; argv++; 33177870Sru } 332177362Ssam } else if (strncmp(argv[0], "blackhole", 9) == 0) { 333177362Ssam flags |= RTF_BLACKHOLE; 334177362Ssam } else if (strncmp(argv[0], "reject", 6) == 0) { 335177362Ssam flags |= RTF_REJECT; 3361553Srgrimes } else if (strncmp(argv[0], "trail", 5) == 0) { 337128192Sluigi /* XXX deprecated and undocumented feature */ 3381553Srgrimes printf("%s: Sending trailers is no longer supported\n", 3391553Srgrimes host); 3401553Srgrimes } 3411553Srgrimes argv++; 3421553Srgrimes } 34393952Sru ea = (struct ether_addr *)LLADDR(&sdl_m); 34413977Sphk if (doing_proxy && !strcmp(eaddr, "auto")) { 345128192Sluigi if (!get_ether_addr(dst->sin_addr.s_addr, ea)) { 34673135Sru printf("no interface found for %s\n", 347128192Sluigi inet_ntoa(dst->sin_addr)); 34813977Sphk return (1); 34913977Sphk } 35093952Sru sdl_m.sdl_alen = ETHER_ADDR_LEN; 35113977Sphk } else { 352128192Sluigi struct ether_addr *ea1 = ether_aton(eaddr); 353128192Sluigi 354155471Sglebius if (ea1 == NULL) { 355128192Sluigi warnx("invalid Ethernet address '%s'", eaddr); 356155471Sglebius return (1); 357155471Sglebius } else { 358128192Sluigi *ea = *ea1; 35993952Sru sdl_m.sdl_alen = ETHER_ADDR_LEN; 360128192Sluigi } 36113977Sphk } 362128192Sluigi for (;;) { /* try at most twice */ 363128192Sluigi rtm = rtmsg(RTM_GET, dst, &sdl_m); 364128192Sluigi if (rtm == NULL) { 365128192Sluigi warn("%s", host); 366128192Sluigi return (1); 367128192Sluigi } 368128192Sluigi addr = (struct sockaddr_inarp *)(rtm + 1); 369128192Sluigi sdl = (struct sockaddr_dl *)(SA_SIZE(addr) + (char *)addr); 370128192Sluigi if (addr->sin_addr.s_addr != dst->sin_addr.s_addr) 371128192Sluigi break; 3721553Srgrimes if (sdl->sdl_family == AF_LINK && 3731553Srgrimes (rtm->rtm_flags & RTF_LLINFO) && 374128192Sluigi !(rtm->rtm_flags & RTF_GATEWAY) && 375128192Sluigi valid_type(sdl->sdl_type) ) 376128192Sluigi break; 3771553Srgrimes if (doing_proxy == 0) { 3781553Srgrimes printf("set: can only proxy for %s\n", host); 3791553Srgrimes return (1); 3801553Srgrimes } 381128192Sluigi if (dst->sin_other & SIN_PROXY) { 3821553Srgrimes printf("set: proxy entry exists for non 802 device\n"); 383147172Sru return (1); 3841553Srgrimes } 385128192Sluigi dst->sin_other = SIN_PROXY; 38677870Sru proxy_only = 1; 3871553Srgrimes } 388128192Sluigi 3891553Srgrimes if (sdl->sdl_family != AF_LINK) { 3901553Srgrimes printf("cannot intuit interface index and type for %s\n", host); 3911553Srgrimes return (1); 3921553Srgrimes } 3931553Srgrimes sdl_m.sdl_type = sdl->sdl_type; 3941553Srgrimes sdl_m.sdl_index = sdl->sdl_index; 395147170Sglebius return (rtmsg(RTM_ADD, dst, &sdl_m) == NULL); 3961553Srgrimes} 3971553Srgrimes 3981553Srgrimes/* 3991553Srgrimes * Display an individual arp entry 4001553Srgrimes */ 401147172Srustatic int 40213977Sphkget(char *host) 4031553Srgrimes{ 404128192Sluigi struct sockaddr_inarp *addr; 4051553Srgrimes 406128192Sluigi addr = getaddr(host); 407128192Sluigi if (addr == NULL) 408147172Sru return (1); 409128181Sluigi if (0 == search(addr->sin_addr.s_addr, print_entry)) { 410117729Syar printf("%s (%s) -- no entry", 41187598Smikeh host, inet_ntoa(addr->sin_addr)); 412117729Syar if (rifname) 413117729Syar printf(" on %s", rifname); 414117729Syar printf("\n"); 415147172Sru return (1); 4161553Srgrimes } 417147172Sru return (0); 4181553Srgrimes} 4191553Srgrimes 4201553Srgrimes/* 4218857Srgrimes * Delete an arp entry 4221553Srgrimes */ 423128181Sluigistatic int 424128192Sluigidelete(char *host, int do_proxy) 4251553Srgrimes{ 426128192Sluigi struct sockaddr_inarp *addr, *dst; 427128181Sluigi struct rt_msghdr *rtm; 4281553Srgrimes struct sockaddr_dl *sdl; 4291553Srgrimes 430128192Sluigi dst = getaddr(host); 431128192Sluigi if (dst == NULL) 432147172Sru return (1); 433128192Sluigi dst->sin_other = do_proxy; 434128192Sluigi for (;;) { /* try twice */ 435128192Sluigi rtm = rtmsg(RTM_GET, dst, NULL); 436128192Sluigi if (rtm == NULL) { 437128192Sluigi warn("%s", host); 4381553Srgrimes return (1); 4391553Srgrimes } 440128192Sluigi addr = (struct sockaddr_inarp *)(rtm + 1); 441128192Sluigi sdl = (struct sockaddr_dl *)(SA_SIZE(addr) + (char *)addr); 442128192Sluigi if (addr->sin_addr.s_addr == dst->sin_addr.s_addr && 443128192Sluigi sdl->sdl_family == AF_LINK && 4441553Srgrimes (rtm->rtm_flags & RTF_LLINFO) && 445128192Sluigi !(rtm->rtm_flags & RTF_GATEWAY) && 446128192Sluigi valid_type(sdl->sdl_type) ) 447128192Sluigi break; /* found it */ 448128192Sluigi if (dst->sin_other & SIN_PROXY) { 449128192Sluigi fprintf(stderr, "delete: cannot locate %s\n",host); 450128192Sluigi return (1); 451128192Sluigi } 452128192Sluigi dst->sin_other = SIN_PROXY; 4531553Srgrimes } 454128192Sluigi if (rtmsg(RTM_DELETE, dst, NULL) != NULL) { 45587598Smikeh printf("%s (%s) deleted\n", host, inet_ntoa(addr->sin_addr)); 45613977Sphk return (0); 45713977Sphk } 45813977Sphk return (1); 4591553Srgrimes} 4601553Srgrimes 4611553Srgrimes/* 46231145Sjulian * Search the arp table and do some action on matching entries 4631553Srgrimes */ 464128181Sluigistatic int 465128181Sluigisearch(u_long addr, action_fn *action) 4661553Srgrimes{ 4671553Srgrimes int mib[6]; 4681553Srgrimes size_t needed; 469140735Smaxim char *lim, *buf, *newbuf, *next; 4701553Srgrimes struct rt_msghdr *rtm; 47187598Smikeh struct sockaddr_inarp *sin2; 4721553Srgrimes struct sockaddr_dl *sdl; 473117729Syar char ifname[IF_NAMESIZE]; 474140735Smaxim int st, found_entry = 0; 4751553Srgrimes 4761553Srgrimes mib[0] = CTL_NET; 4771553Srgrimes mib[1] = PF_ROUTE; 4781553Srgrimes mib[2] = 0; 4791553Srgrimes mib[3] = AF_INET; 4801553Srgrimes mib[4] = NET_RT_FLAGS; 4811553Srgrimes mib[5] = RTF_LLINFO; 4821553Srgrimes if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0) 483128054Smux err(1, "route-sysctl-estimate"); 484128192Sluigi if (needed == 0) /* empty table */ 485128181Sluigi return 0; 486140735Smaxim buf = NULL; 487140748Smaxim for (;;) { 488140735Smaxim newbuf = realloc(buf, needed); 489140735Smaxim if (newbuf == NULL) { 490140735Smaxim if (buf != NULL) 491140735Smaxim free(buf); 492140735Smaxim errx(1, "could not reallocate memory"); 493140735Smaxim } 494140735Smaxim buf = newbuf; 495140735Smaxim st = sysctl(mib, 6, buf, &needed, NULL, 0); 496140748Smaxim if (st == 0 || errno != ENOMEM) 497140748Smaxim break; 498140748Smaxim needed += needed / 8; 499140748Smaxim } 500140735Smaxim if (st == -1) 501128054Smux err(1, "actual retrieval of routing table"); 5021553Srgrimes lim = buf + needed; 5031553Srgrimes for (next = buf; next < lim; next += rtm->rtm_msglen) { 5041553Srgrimes rtm = (struct rt_msghdr *)next; 50587598Smikeh sin2 = (struct sockaddr_inarp *)(rtm + 1); 506130246Sstefanf sdl = (struct sockaddr_dl *)((char *)sin2 + SA_SIZE(sin2)); 507117729Syar if (rifname && if_indextoname(sdl->sdl_index, ifname) && 508117729Syar strcmp(ifname, rifname)) 509117729Syar continue; 5101553Srgrimes if (addr) { 51187598Smikeh if (addr != sin2->sin_addr.s_addr) 5121553Srgrimes continue; 5131553Srgrimes found_entry = 1; 5141553Srgrimes } 51587598Smikeh (*action)(sdl, sin2, rtm); 5161553Srgrimes } 51776216Syar free(buf); 518147172Sru return (found_entry); 5191553Srgrimes} 5201553Srgrimes 52131145Sjulian/* 52231145Sjulian * Display an arp entry 52331145Sjulian */ 524128181Sluigistatic void 52531145Sjulianprint_entry(struct sockaddr_dl *sdl, 52687598Smikeh struct sockaddr_inarp *addr, struct rt_msghdr *rtm) 52731145Sjulian{ 52877870Sru const char *host; 52931145Sjulian struct hostent *hp; 53096202Skbyanc struct iso88025_sockaddr_dl_data *trld; 53184666Sru char ifname[IF_NAMESIZE]; 53244627Sjulian int seg; 53331145Sjulian 53431145Sjulian if (nflag == 0) 53587598Smikeh hp = gethostbyaddr((caddr_t)&(addr->sin_addr), 53687598Smikeh sizeof addr->sin_addr, AF_INET); 53731145Sjulian else 53831145Sjulian hp = 0; 53931145Sjulian if (hp) 54031145Sjulian host = hp->h_name; 54131145Sjulian else { 54231145Sjulian host = "?"; 54331145Sjulian if (h_errno == TRY_AGAIN) 54431145Sjulian nflag = 1; 54531145Sjulian } 54687598Smikeh printf("%s (%s) at ", host, inet_ntoa(addr->sin_addr)); 547130408Sdfr if (sdl->sdl_alen) { 548139270Sru if ((sdl->sdl_type == IFT_ETHER || 549151989Sthompsa sdl->sdl_type == IFT_L2VLAN || 550151989Sthompsa sdl->sdl_type == IFT_BRIDGE) && 551130408Sdfr sdl->sdl_alen == ETHER_ADDR_LEN) 552130408Sdfr printf("%s", ether_ntoa((struct ether_addr *)LLADDR(sdl))); 553130408Sdfr else { 554130408Sdfr int n = sdl->sdl_nlen > 0 ? sdl->sdl_nlen + 1 : 0; 555130408Sdfr 556130408Sdfr printf("%s", link_ntoa(sdl) + n); 557130408Sdfr } 558130408Sdfr } else 55931145Sjulian printf("(incomplete)"); 56084666Sru if (if_indextoname(sdl->sdl_index, ifname) != NULL) 56184666Sru printf(" on %s", ifname); 56231145Sjulian if (rtm->rtm_rmx.rmx_expire == 0) 56331145Sjulian printf(" permanent"); 56487598Smikeh if (addr->sin_other & SIN_PROXY) 56531145Sjulian printf(" published (proxy only)"); 56631145Sjulian if (rtm->rtm_addrs & RTA_NETMASK) { 56787598Smikeh addr = (struct sockaddr_inarp *) 568128186Sluigi (SA_SIZE(sdl) + (char *)sdl); 56987598Smikeh if (addr->sin_addr.s_addr == 0xffffffff) 57031145Sjulian printf(" published"); 57187598Smikeh if (addr->sin_len != 8) 57251250Sru printf("(weird)"); 57331145Sjulian } 57444627Sjulian switch(sdl->sdl_type) { 575128181Sluigi case IFT_ETHER: 57644627Sjulian printf(" [ethernet]"); 57744627Sjulian break; 578128181Sluigi case IFT_ISO88025: 57944627Sjulian printf(" [token-ring]"); 58096202Skbyanc trld = SDL_ISO88025(sdl); 58196202Skbyanc if (trld->trld_rcf != 0) { 58296202Skbyanc printf(" rt=%x", ntohs(trld->trld_rcf)); 58396202Skbyanc for (seg = 0; 58496202Skbyanc seg < ((TR_RCF_RIFLEN(trld->trld_rcf) - 2 ) / 2); 58596202Skbyanc seg++) 58696235Swpaul printf(":%x", ntohs(*(trld->trld_route[seg]))); 58796202Skbyanc } 58844627Sjulian break; 589128181Sluigi case IFT_FDDI: 59085123Smdodd printf(" [fddi]"); 59185123Smdodd break; 592128181Sluigi case IFT_ATM: 59385123Smdodd printf(" [atm]"); 59485123Smdodd break; 595128181Sluigi case IFT_L2VLAN: 59675180Syar printf(" [vlan]"); 59775180Syar break; 598130408Sdfr case IFT_IEEE1394: 599130408Sdfr printf(" [firewire]"); 600130408Sdfr break; 601151989Sthompsa case IFT_BRIDGE: 602151989Sthompsa printf(" [bridge]"); 603151989Sthompsa break; 604128181Sluigi default: 60594075Smurray break; 60644627Sjulian } 60744627Sjulian 60831145Sjulian printf("\n"); 60944627Sjulian 61031145Sjulian} 61131145Sjulian 61231145Sjulian/* 61331145Sjulian * Nuke an arp entry 61431145Sjulian */ 615128181Sluigistatic void 61687598Smikehnuke_entry(struct sockaddr_dl *sdl __unused, 61787598Smikeh struct sockaddr_inarp *addr, struct rt_msghdr *rtm __unused) 61831145Sjulian{ 61931145Sjulian char ip[20]; 62031145Sjulian 62187598Smikeh snprintf(ip, sizeof(ip), "%s", inet_ntoa(addr->sin_addr)); 622147172Sru (void)delete(ip, 0); 62331145Sjulian} 62431145Sjulian 625128181Sluigistatic void 62613977Sphkusage(void) 6271553Srgrimes{ 62831145Sjulian fprintf(stderr, "%s\n%s\n%s\n%s\n%s\n%s\n%s\n", 629117729Syar "usage: arp [-n] [-i interface] hostname", 630117729Syar " arp [-n] [-i interface] -a", 63177870Sru " arp -d hostname [pub]", 632154191Sbrooks " arp -d [-i interface] -a", 633177362Ssam " arp -s hostname ether_addr [temp] [reject] [blackhole] [pub [only]]", 634177362Ssam " arp -S hostname ether_addr [temp] [reject] [blackhole] [pub [only]]", 63529060Scharnier " arp -f filename"); 6361553Srgrimes exit(1); 6371553Srgrimes} 6381553Srgrimes 639128181Sluigistatic struct rt_msghdr * 640128192Sluigirtmsg(int cmd, struct sockaddr_inarp *dst, struct sockaddr_dl *sdl) 6411553Srgrimes{ 6421553Srgrimes static int seq; 6431553Srgrimes int rlen; 644128181Sluigi int l; 645175206Ssam struct sockaddr_in so_mask, *som = &so_mask; 646128181Sluigi static int s = -1; 647128181Sluigi static pid_t pid; 648128181Sluigi 649128181Sluigi static struct { 650128181Sluigi struct rt_msghdr m_rtm; 651128181Sluigi char m_space[512]; 652128181Sluigi } m_rtmsg; 653128181Sluigi 654128054Smux struct rt_msghdr *rtm = &m_rtmsg.m_rtm; 655128054Smux char *cp = m_rtmsg.m_space; 6561553Srgrimes 657128181Sluigi if (s < 0) { /* first time: open socket, get pid */ 658128181Sluigi s = socket(PF_ROUTE, SOCK_RAW, 0); 659128181Sluigi if (s < 0) 660128181Sluigi err(1, "socket"); 661128181Sluigi pid = getpid(); 662128181Sluigi } 663128181Sluigi bzero(&so_mask, sizeof(so_mask)); 664128181Sluigi so_mask.sin_len = 8; 665128181Sluigi so_mask.sin_addr.s_addr = 0xffffffff; 666128181Sluigi 6671553Srgrimes errno = 0; 668128192Sluigi /* 669128192Sluigi * XXX RTM_DELETE relies on a previous RTM_GET to fill the buffer 670128192Sluigi * appropriately. 671128192Sluigi */ 6721553Srgrimes if (cmd == RTM_DELETE) 6731553Srgrimes goto doit; 6741553Srgrimes bzero((char *)&m_rtmsg, sizeof(m_rtmsg)); 6751553Srgrimes rtm->rtm_flags = flags; 6761553Srgrimes rtm->rtm_version = RTM_VERSION; 6771553Srgrimes 6781553Srgrimes switch (cmd) { 6791553Srgrimes default: 68029060Scharnier errx(1, "internal wrong cmd"); 6811553Srgrimes case RTM_ADD: 6821553Srgrimes rtm->rtm_addrs |= RTA_GATEWAY; 6831553Srgrimes rtm->rtm_rmx.rmx_expire = expire_time; 6841553Srgrimes rtm->rtm_inits = RTV_EXPIRE; 6851553Srgrimes rtm->rtm_flags |= (RTF_HOST | RTF_STATIC); 686128192Sluigi dst->sin_other = 0; 6871553Srgrimes if (doing_proxy) { 68877870Sru if (proxy_only) 689128192Sluigi dst->sin_other = SIN_PROXY; 6901553Srgrimes else { 6911553Srgrimes rtm->rtm_addrs |= RTA_NETMASK; 6921553Srgrimes rtm->rtm_flags &= ~RTF_HOST; 6931553Srgrimes } 6941553Srgrimes } 6951553Srgrimes /* FALLTHROUGH */ 6961553Srgrimes case RTM_GET: 6971553Srgrimes rtm->rtm_addrs |= RTA_DST; 6981553Srgrimes } 6991553Srgrimes#define NEXTADDR(w, s) \ 700147172Sru if ((s) != NULL && rtm->rtm_addrs & (w)) { \ 701147172Sru bcopy((s), cp, sizeof(*(s))); cp += SA_SIZE(s);} 7021553Srgrimes 703128192Sluigi NEXTADDR(RTA_DST, dst); 704128192Sluigi NEXTADDR(RTA_GATEWAY, sdl); 705175206Ssam NEXTADDR(RTA_NETMASK, som); 7061553Srgrimes 7071553Srgrimes rtm->rtm_msglen = cp - (char *)&m_rtmsg; 7081553Srgrimesdoit: 7091553Srgrimes l = rtm->rtm_msglen; 7101553Srgrimes rtm->rtm_seq = ++seq; 7111553Srgrimes rtm->rtm_type = cmd; 7121553Srgrimes if ((rlen = write(s, (char *)&m_rtmsg, l)) < 0) { 7131553Srgrimes if (errno != ESRCH || cmd != RTM_DELETE) { 71429060Scharnier warn("writing to routing socket"); 715147172Sru return (NULL); 7161553Srgrimes } 7171553Srgrimes } 7181553Srgrimes do { 7191553Srgrimes l = read(s, (char *)&m_rtmsg, sizeof(m_rtmsg)); 7201553Srgrimes } while (l > 0 && (rtm->rtm_seq != seq || rtm->rtm_pid != pid)); 7211553Srgrimes if (l < 0) 72229060Scharnier warn("read from routing socket"); 723147172Sru return (rtm); 7241553Srgrimes} 7251553Srgrimes 72613977Sphk/* 72713977Sphk * get_ether_addr - get the hardware address of an interface on the 72813977Sphk * the same subnet as ipaddr. 72913977Sphk */ 73013977Sphk#define MAX_IFS 32 73113977Sphk 732128181Sluigistatic int 733147172Sruget_ether_addr(in_addr_t ipaddr, struct ether_addr *hwaddr) 73413977Sphk{ 73513977Sphk struct ifreq *ifr, *ifend, *ifp; 736147172Sru in_addr_t ina, mask; 73713977Sphk struct sockaddr_dl *dla; 73813977Sphk struct ifreq ifreq; 73913977Sphk struct ifconf ifc; 74013977Sphk struct ifreq ifs[MAX_IFS]; 74187598Smikeh int sock; 742128192Sluigi int retval = 0; 74313977Sphk 74487598Smikeh sock = socket(AF_INET, SOCK_DGRAM, 0); 74587598Smikeh if (sock < 0) 74629060Scharnier err(1, "socket"); 74713977Sphk 74813977Sphk ifc.ifc_len = sizeof(ifs); 74913977Sphk ifc.ifc_req = ifs; 75092735Smikeh if (ioctl(sock, SIOCGIFCONF, &ifc) < 0) { 75129060Scharnier warnx("ioctl(SIOCGIFCONF)"); 752128192Sluigi goto done; 75313977Sphk } 75413977Sphk 755128192Sluigi#define NEXTIFR(i) \ 756128192Sluigi ((struct ifreq *)((char *)&(i)->ifr_addr \ 757128192Sluigi + MAX((i)->ifr_addr.sa_len, sizeof((i)->ifr_addr))) ) 758128192Sluigi 75913977Sphk /* 760128192Sluigi * Scan through looking for an interface with an Internet 761128192Sluigi * address on the same subnet as `ipaddr'. 762128192Sluigi */ 763128192Sluigi ifend = (struct ifreq *)(ifc.ifc_buf + ifc.ifc_len); 764128192Sluigi for (ifr = ifc.ifc_req; ifr < ifend; ifr = NEXTIFR(ifr) ) { 765128192Sluigi if (ifr->ifr_addr.sa_family != AF_INET) 766128192Sluigi continue; 767128192Sluigi strncpy(ifreq.ifr_name, ifr->ifr_name, 768128192Sluigi sizeof(ifreq.ifr_name)); 769163305Sglebius ifreq.ifr_addr = ifr->ifr_addr; 770128192Sluigi /* 771128192Sluigi * Check that the interface is up, 772128192Sluigi * and not point-to-point or loopback. 773128192Sluigi */ 774128192Sluigi if (ioctl(sock, SIOCGIFFLAGS, &ifreq) < 0) 775128192Sluigi continue; 776128192Sluigi if ((ifreq.ifr_flags & 777128192Sluigi (IFF_UP|IFF_BROADCAST|IFF_POINTOPOINT| 778128192Sluigi IFF_LOOPBACK|IFF_NOARP)) 779128192Sluigi != (IFF_UP|IFF_BROADCAST)) 780128192Sluigi continue; 781128192Sluigi /* 782128192Sluigi * Get its netmask and check that it's on 783128192Sluigi * the right subnet. 784128192Sluigi */ 785128192Sluigi if (ioctl(sock, SIOCGIFNETMASK, &ifreq) < 0) 786128192Sluigi continue; 787128192Sluigi mask = ((struct sockaddr_in *) 788128192Sluigi &ifreq.ifr_addr)->sin_addr.s_addr; 789128192Sluigi ina = ((struct sockaddr_in *) 790128192Sluigi &ifr->ifr_addr)->sin_addr.s_addr; 791128192Sluigi if ((ipaddr & mask) == (ina & mask)) 792128192Sluigi break; /* ok, we got it! */ 79313977Sphk } 79413977Sphk 795128192Sluigi if (ifr >= ifend) 796128192Sluigi goto done; 79713977Sphk 79813977Sphk /* 799128192Sluigi * Now scan through again looking for a link-level address 800128192Sluigi * for this interface. 801128192Sluigi */ 80213977Sphk ifp = ifr; 803128192Sluigi for (ifr = ifc.ifc_req; ifr < ifend; ifr = NEXTIFR(ifr)) 804128192Sluigi if (strcmp(ifp->ifr_name, ifr->ifr_name) == 0 && 805128192Sluigi ifr->ifr_addr.sa_family == AF_LINK) 806128192Sluigi break; 807128192Sluigi if (ifr >= ifend) 808128192Sluigi goto done; 809128192Sluigi /* 810128192Sluigi * Found the link-level address - copy it out 811128192Sluigi */ 812128192Sluigi dla = (struct sockaddr_dl *) &ifr->ifr_addr; 813128192Sluigi memcpy(hwaddr, LLADDR(dla), dla->sdl_alen); 814128192Sluigi printf("using interface %s for proxy with address ", 815128192Sluigi ifp->ifr_name); 816128192Sluigi printf("%s\n", ether_ntoa(hwaddr)); 817128192Sluigi retval = dla->sdl_alen; 818128192Sluigidone: 819128192Sluigi close(sock); 820147172Sru return (retval); 82113977Sphk} 822