arp.c revision 186500
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 186500 2008-12-26 19:45:24Z qingli $"); 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) { 333186485Strhodes if (flags & RTF_REJECT) { 334186485Strhodes printf("Choose one of blackhole or reject, not both.\n"); 335186485Strhodes } 336177362Ssam flags |= RTF_BLACKHOLE; 337177362Ssam } else if (strncmp(argv[0], "reject", 6) == 0) { 338186485Strhodes if (flags & RTF_BLACKHOLE) { 339186485Strhodes printf("Choose one of blackhole or reject, not both.\n"); 340186485Strhodes } 341177362Ssam flags |= RTF_REJECT; 3421553Srgrimes } else if (strncmp(argv[0], "trail", 5) == 0) { 343128192Sluigi /* XXX deprecated and undocumented feature */ 3441553Srgrimes printf("%s: Sending trailers is no longer supported\n", 3451553Srgrimes host); 3461553Srgrimes } 3471553Srgrimes argv++; 3481553Srgrimes } 34993952Sru ea = (struct ether_addr *)LLADDR(&sdl_m); 35013977Sphk if (doing_proxy && !strcmp(eaddr, "auto")) { 351128192Sluigi if (!get_ether_addr(dst->sin_addr.s_addr, ea)) { 35273135Sru printf("no interface found for %s\n", 353128192Sluigi inet_ntoa(dst->sin_addr)); 35413977Sphk return (1); 35513977Sphk } 35693952Sru sdl_m.sdl_alen = ETHER_ADDR_LEN; 35713977Sphk } else { 358128192Sluigi struct ether_addr *ea1 = ether_aton(eaddr); 359128192Sluigi 360155471Sglebius if (ea1 == NULL) { 361128192Sluigi warnx("invalid Ethernet address '%s'", eaddr); 362155471Sglebius return (1); 363155471Sglebius } else { 364128192Sluigi *ea = *ea1; 36593952Sru sdl_m.sdl_alen = ETHER_ADDR_LEN; 366128192Sluigi } 36713977Sphk } 368128192Sluigi for (;;) { /* try at most twice */ 369128192Sluigi rtm = rtmsg(RTM_GET, dst, &sdl_m); 370128192Sluigi if (rtm == NULL) { 371128192Sluigi warn("%s", host); 372128192Sluigi return (1); 373128192Sluigi } 374128192Sluigi addr = (struct sockaddr_inarp *)(rtm + 1); 375128192Sluigi sdl = (struct sockaddr_dl *)(SA_SIZE(addr) + (char *)addr); 376128192Sluigi if (addr->sin_addr.s_addr != dst->sin_addr.s_addr) 377128192Sluigi break; 3781553Srgrimes if (sdl->sdl_family == AF_LINK && 379128192Sluigi !(rtm->rtm_flags & RTF_GATEWAY) && 380128192Sluigi valid_type(sdl->sdl_type) ) 381128192Sluigi break; 3821553Srgrimes if (doing_proxy == 0) { 3831553Srgrimes printf("set: can only proxy for %s\n", host); 3841553Srgrimes return (1); 3851553Srgrimes } 386128192Sluigi if (dst->sin_other & SIN_PROXY) { 3871553Srgrimes printf("set: proxy entry exists for non 802 device\n"); 388147172Sru return (1); 3891553Srgrimes } 390128192Sluigi dst->sin_other = SIN_PROXY; 39177870Sru proxy_only = 1; 3921553Srgrimes } 393128192Sluigi 3941553Srgrimes if (sdl->sdl_family != AF_LINK) { 3951553Srgrimes printf("cannot intuit interface index and type for %s\n", host); 3961553Srgrimes return (1); 3971553Srgrimes } 3981553Srgrimes sdl_m.sdl_type = sdl->sdl_type; 3991553Srgrimes sdl_m.sdl_index = sdl->sdl_index; 400147170Sglebius return (rtmsg(RTM_ADD, dst, &sdl_m) == NULL); 4011553Srgrimes} 4021553Srgrimes 4031553Srgrimes/* 4041553Srgrimes * Display an individual arp entry 4051553Srgrimes */ 406147172Srustatic int 40713977Sphkget(char *host) 4081553Srgrimes{ 409128192Sluigi struct sockaddr_inarp *addr; 4101553Srgrimes 411128192Sluigi addr = getaddr(host); 412128192Sluigi if (addr == NULL) 413147172Sru return (1); 414128181Sluigi if (0 == search(addr->sin_addr.s_addr, print_entry)) { 415117729Syar printf("%s (%s) -- no entry", 41687598Smikeh host, inet_ntoa(addr->sin_addr)); 417117729Syar if (rifname) 418117729Syar printf(" on %s", rifname); 419117729Syar printf("\n"); 420147172Sru return (1); 4211553Srgrimes } 422147172Sru return (0); 4231553Srgrimes} 4241553Srgrimes 4251553Srgrimes/* 4268857Srgrimes * Delete an arp entry 4271553Srgrimes */ 428128181Sluigistatic int 429128192Sluigidelete(char *host, int do_proxy) 4301553Srgrimes{ 431128192Sluigi struct sockaddr_inarp *addr, *dst; 432128181Sluigi struct rt_msghdr *rtm; 4331553Srgrimes struct sockaddr_dl *sdl; 434186119Sqingli struct sockaddr_dl sdl_m; 4351553Srgrimes 436128192Sluigi dst = getaddr(host); 437128192Sluigi if (dst == NULL) 438147172Sru return (1); 439128192Sluigi dst->sin_other = do_proxy; 440186119Sqingli 441186119Sqingli /* 442186119Sqingli * setup the data structure to notify the kernel 443186119Sqingli * it is the ARP entry the RTM_GET is interested 444186119Sqingli * in 445186119Sqingli */ 446186119Sqingli bzero(&sdl_m, sizeof(sdl_m)); 447186119Sqingli sdl_m.sdl_len = sizeof(sdl_m); 448186119Sqingli sdl_m.sdl_family = AF_LINK; 449186119Sqingli 450128192Sluigi for (;;) { /* try twice */ 451186119Sqingli rtm = rtmsg(RTM_GET, dst, &sdl_m); 452128192Sluigi if (rtm == NULL) { 453128192Sluigi warn("%s", host); 4541553Srgrimes return (1); 4551553Srgrimes } 456128192Sluigi addr = (struct sockaddr_inarp *)(rtm + 1); 457128192Sluigi sdl = (struct sockaddr_dl *)(SA_SIZE(addr) + (char *)addr); 458186119Sqingli 459186119Sqingli /* 460186119Sqingli * With the new L2/L3 restructure, the route 461186119Sqingli * returned is a prefix route. The important 462186119Sqingli * piece of information from the previous 463186119Sqingli * RTM_GET is the interface index. In the 464186119Sqingli * case of ECMP, the kernel will traverse 465186119Sqingli * the route group for the given entry. 466186119Sqingli */ 467186119Sqingli if (sdl->sdl_family == AF_LINK && 468128192Sluigi !(rtm->rtm_flags & RTF_GATEWAY) && 469186119Sqingli valid_type(sdl->sdl_type) ) { 470186119Sqingli addr->sin_addr.s_addr = dst->sin_addr.s_addr; 471186119Sqingli break; 472186119Sqingli } 473186119Sqingli 474128192Sluigi if (dst->sin_other & SIN_PROXY) { 475128192Sluigi fprintf(stderr, "delete: cannot locate %s\n",host); 476128192Sluigi return (1); 477128192Sluigi } 478128192Sluigi dst->sin_other = SIN_PROXY; 4791553Srgrimes } 480186500Sqingli rtm->rtm_flags |= RTF_LLDATA; 481128192Sluigi if (rtmsg(RTM_DELETE, dst, NULL) != NULL) { 48287598Smikeh printf("%s (%s) deleted\n", host, inet_ntoa(addr->sin_addr)); 48313977Sphk return (0); 48413977Sphk } 48513977Sphk return (1); 4861553Srgrimes} 4871553Srgrimes 4881553Srgrimes/* 48931145Sjulian * Search the arp table and do some action on matching entries 4901553Srgrimes */ 491128181Sluigistatic int 492128181Sluigisearch(u_long addr, action_fn *action) 4931553Srgrimes{ 4941553Srgrimes int mib[6]; 4951553Srgrimes size_t needed; 496140735Smaxim char *lim, *buf, *newbuf, *next; 4971553Srgrimes struct rt_msghdr *rtm; 49887598Smikeh struct sockaddr_inarp *sin2; 4991553Srgrimes struct sockaddr_dl *sdl; 500117729Syar char ifname[IF_NAMESIZE]; 501140735Smaxim int st, found_entry = 0; 5021553Srgrimes 5031553Srgrimes mib[0] = CTL_NET; 5041553Srgrimes mib[1] = PF_ROUTE; 5051553Srgrimes mib[2] = 0; 5061553Srgrimes mib[3] = AF_INET; 5071553Srgrimes mib[4] = NET_RT_FLAGS; 508186119Sqingli#ifdef RTF_LLINFO 5091553Srgrimes mib[5] = RTF_LLINFO; 510186119Sqingli#else 511186119Sqingli mib[5] = 0; 512186119Sqingli#endif 5131553Srgrimes if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0) 514128054Smux err(1, "route-sysctl-estimate"); 515128192Sluigi if (needed == 0) /* empty table */ 516128181Sluigi return 0; 517140735Smaxim buf = NULL; 518140748Smaxim for (;;) { 519140735Smaxim newbuf = realloc(buf, needed); 520140735Smaxim if (newbuf == NULL) { 521140735Smaxim if (buf != NULL) 522140735Smaxim free(buf); 523140735Smaxim errx(1, "could not reallocate memory"); 524140735Smaxim } 525140735Smaxim buf = newbuf; 526140735Smaxim st = sysctl(mib, 6, buf, &needed, NULL, 0); 527140748Smaxim if (st == 0 || errno != ENOMEM) 528140748Smaxim break; 529140748Smaxim needed += needed / 8; 530140748Smaxim } 531140735Smaxim if (st == -1) 532128054Smux err(1, "actual retrieval of routing table"); 5331553Srgrimes lim = buf + needed; 5341553Srgrimes for (next = buf; next < lim; next += rtm->rtm_msglen) { 5351553Srgrimes rtm = (struct rt_msghdr *)next; 53687598Smikeh sin2 = (struct sockaddr_inarp *)(rtm + 1); 537130246Sstefanf sdl = (struct sockaddr_dl *)((char *)sin2 + SA_SIZE(sin2)); 538117729Syar if (rifname && if_indextoname(sdl->sdl_index, ifname) && 539117729Syar strcmp(ifname, rifname)) 540117729Syar continue; 5411553Srgrimes if (addr) { 54287598Smikeh if (addr != sin2->sin_addr.s_addr) 5431553Srgrimes continue; 5441553Srgrimes found_entry = 1; 5451553Srgrimes } 54687598Smikeh (*action)(sdl, sin2, rtm); 5471553Srgrimes } 54876216Syar free(buf); 549147172Sru return (found_entry); 5501553Srgrimes} 5511553Srgrimes 55231145Sjulian/* 55331145Sjulian * Display an arp entry 55431145Sjulian */ 555128181Sluigistatic void 55631145Sjulianprint_entry(struct sockaddr_dl *sdl, 55787598Smikeh struct sockaddr_inarp *addr, struct rt_msghdr *rtm) 55831145Sjulian{ 55977870Sru const char *host; 56031145Sjulian struct hostent *hp; 56196202Skbyanc struct iso88025_sockaddr_dl_data *trld; 56284666Sru char ifname[IF_NAMESIZE]; 56344627Sjulian int seg; 56431145Sjulian 56531145Sjulian if (nflag == 0) 56687598Smikeh hp = gethostbyaddr((caddr_t)&(addr->sin_addr), 56787598Smikeh sizeof addr->sin_addr, AF_INET); 56831145Sjulian else 56931145Sjulian hp = 0; 57031145Sjulian if (hp) 57131145Sjulian host = hp->h_name; 57231145Sjulian else { 57331145Sjulian host = "?"; 57431145Sjulian if (h_errno == TRY_AGAIN) 57531145Sjulian nflag = 1; 57631145Sjulian } 57787598Smikeh printf("%s (%s) at ", host, inet_ntoa(addr->sin_addr)); 578130408Sdfr if (sdl->sdl_alen) { 579139270Sru if ((sdl->sdl_type == IFT_ETHER || 580151989Sthompsa sdl->sdl_type == IFT_L2VLAN || 581151989Sthompsa sdl->sdl_type == IFT_BRIDGE) && 582130408Sdfr sdl->sdl_alen == ETHER_ADDR_LEN) 583130408Sdfr printf("%s", ether_ntoa((struct ether_addr *)LLADDR(sdl))); 584130408Sdfr else { 585130408Sdfr int n = sdl->sdl_nlen > 0 ? sdl->sdl_nlen + 1 : 0; 586130408Sdfr 587130408Sdfr printf("%s", link_ntoa(sdl) + n); 588130408Sdfr } 589130408Sdfr } else 59031145Sjulian printf("(incomplete)"); 59184666Sru if (if_indextoname(sdl->sdl_index, ifname) != NULL) 59284666Sru printf(" on %s", ifname); 59331145Sjulian if (rtm->rtm_rmx.rmx_expire == 0) 59431145Sjulian printf(" permanent"); 59587598Smikeh if (addr->sin_other & SIN_PROXY) 59631145Sjulian printf(" published (proxy only)"); 597186119Sqingli if (rtm->rtm_flags & RTF_ANNOUNCE) 598186119Sqingli printf(" published"); 599186119Sqingli switch(sdl->sdl_type) { 600128181Sluigi case IFT_ETHER: 60144627Sjulian printf(" [ethernet]"); 60244627Sjulian break; 603128181Sluigi case IFT_ISO88025: 60444627Sjulian printf(" [token-ring]"); 60596202Skbyanc trld = SDL_ISO88025(sdl); 60696202Skbyanc if (trld->trld_rcf != 0) { 60796202Skbyanc printf(" rt=%x", ntohs(trld->trld_rcf)); 60896202Skbyanc for (seg = 0; 60996202Skbyanc seg < ((TR_RCF_RIFLEN(trld->trld_rcf) - 2 ) / 2); 61096202Skbyanc seg++) 61196235Swpaul printf(":%x", ntohs(*(trld->trld_route[seg]))); 61296202Skbyanc } 61344627Sjulian break; 614128181Sluigi case IFT_FDDI: 61585123Smdodd printf(" [fddi]"); 61685123Smdodd break; 617128181Sluigi case IFT_ATM: 61885123Smdodd printf(" [atm]"); 61985123Smdodd break; 620128181Sluigi case IFT_L2VLAN: 62175180Syar printf(" [vlan]"); 62275180Syar break; 623130408Sdfr case IFT_IEEE1394: 624130408Sdfr printf(" [firewire]"); 625130408Sdfr break; 626151989Sthompsa case IFT_BRIDGE: 627151989Sthompsa printf(" [bridge]"); 628151989Sthompsa break; 629128181Sluigi default: 63094075Smurray break; 63144627Sjulian } 63244627Sjulian 63331145Sjulian printf("\n"); 63444627Sjulian 63531145Sjulian} 63631145Sjulian 63731145Sjulian/* 63831145Sjulian * Nuke an arp entry 63931145Sjulian */ 640128181Sluigistatic void 64187598Smikehnuke_entry(struct sockaddr_dl *sdl __unused, 64287598Smikeh struct sockaddr_inarp *addr, struct rt_msghdr *rtm __unused) 64331145Sjulian{ 64431145Sjulian char ip[20]; 64531145Sjulian 64687598Smikeh snprintf(ip, sizeof(ip), "%s", inet_ntoa(addr->sin_addr)); 647147172Sru (void)delete(ip, 0); 64831145Sjulian} 64931145Sjulian 650128181Sluigistatic void 65113977Sphkusage(void) 6521553Srgrimes{ 65331145Sjulian fprintf(stderr, "%s\n%s\n%s\n%s\n%s\n%s\n%s\n", 654117729Syar "usage: arp [-n] [-i interface] hostname", 655117729Syar " arp [-n] [-i interface] -a", 65677870Sru " arp -d hostname [pub]", 657154191Sbrooks " arp -d [-i interface] -a", 658186485Strhodes " arp -s hostname ether_addr [temp] [reject | blackhole] [pub [only]]", 659186485Strhodes " arp -S hostname ether_addr [temp] [reject | blackhole] [pub [only]]", 66029060Scharnier " arp -f filename"); 6611553Srgrimes exit(1); 6621553Srgrimes} 6631553Srgrimes 664128181Sluigistatic struct rt_msghdr * 665128192Sluigirtmsg(int cmd, struct sockaddr_inarp *dst, struct sockaddr_dl *sdl) 6661553Srgrimes{ 6671553Srgrimes static int seq; 6681553Srgrimes int rlen; 669128181Sluigi int l; 670175206Ssam struct sockaddr_in so_mask, *som = &so_mask; 671128181Sluigi static int s = -1; 672128181Sluigi static pid_t pid; 673128181Sluigi 674128181Sluigi static struct { 675128181Sluigi struct rt_msghdr m_rtm; 676128181Sluigi char m_space[512]; 677128181Sluigi } m_rtmsg; 678128181Sluigi 679128054Smux struct rt_msghdr *rtm = &m_rtmsg.m_rtm; 680128054Smux char *cp = m_rtmsg.m_space; 6811553Srgrimes 682128181Sluigi if (s < 0) { /* first time: open socket, get pid */ 683128181Sluigi s = socket(PF_ROUTE, SOCK_RAW, 0); 684128181Sluigi if (s < 0) 685128181Sluigi err(1, "socket"); 686128181Sluigi pid = getpid(); 687128181Sluigi } 688128181Sluigi bzero(&so_mask, sizeof(so_mask)); 689128181Sluigi so_mask.sin_len = 8; 690128181Sluigi so_mask.sin_addr.s_addr = 0xffffffff; 691128181Sluigi 6921553Srgrimes errno = 0; 693128192Sluigi /* 694128192Sluigi * XXX RTM_DELETE relies on a previous RTM_GET to fill the buffer 695128192Sluigi * appropriately. 696128192Sluigi */ 6971553Srgrimes if (cmd == RTM_DELETE) 6981553Srgrimes goto doit; 6991553Srgrimes bzero((char *)&m_rtmsg, sizeof(m_rtmsg)); 7001553Srgrimes rtm->rtm_flags = flags; 7011553Srgrimes rtm->rtm_version = RTM_VERSION; 7021553Srgrimes 7031553Srgrimes switch (cmd) { 7041553Srgrimes default: 70529060Scharnier errx(1, "internal wrong cmd"); 7061553Srgrimes case RTM_ADD: 7071553Srgrimes rtm->rtm_addrs |= RTA_GATEWAY; 7081553Srgrimes rtm->rtm_rmx.rmx_expire = expire_time; 7091553Srgrimes rtm->rtm_inits = RTV_EXPIRE; 710186500Sqingli rtm->rtm_flags |= (RTF_HOST | RTF_STATIC | RTF_LLDATA); 711128192Sluigi dst->sin_other = 0; 7121553Srgrimes if (doing_proxy) { 71377870Sru if (proxy_only) 714128192Sluigi dst->sin_other = SIN_PROXY; 7151553Srgrimes else { 7161553Srgrimes rtm->rtm_addrs |= RTA_NETMASK; 7171553Srgrimes rtm->rtm_flags &= ~RTF_HOST; 7181553Srgrimes } 7191553Srgrimes } 7201553Srgrimes /* FALLTHROUGH */ 7211553Srgrimes case RTM_GET: 7221553Srgrimes rtm->rtm_addrs |= RTA_DST; 7231553Srgrimes } 7241553Srgrimes#define NEXTADDR(w, s) \ 725147172Sru if ((s) != NULL && rtm->rtm_addrs & (w)) { \ 726147172Sru bcopy((s), cp, sizeof(*(s))); cp += SA_SIZE(s);} 7271553Srgrimes 728128192Sluigi NEXTADDR(RTA_DST, dst); 729128192Sluigi NEXTADDR(RTA_GATEWAY, sdl); 730175206Ssam NEXTADDR(RTA_NETMASK, som); 7311553Srgrimes 7321553Srgrimes rtm->rtm_msglen = cp - (char *)&m_rtmsg; 7331553Srgrimesdoit: 7341553Srgrimes l = rtm->rtm_msglen; 7351553Srgrimes rtm->rtm_seq = ++seq; 7361553Srgrimes rtm->rtm_type = cmd; 7371553Srgrimes if ((rlen = write(s, (char *)&m_rtmsg, l)) < 0) { 7381553Srgrimes if (errno != ESRCH || cmd != RTM_DELETE) { 73929060Scharnier warn("writing to routing socket"); 740147172Sru return (NULL); 7411553Srgrimes } 7421553Srgrimes } 7431553Srgrimes do { 7441553Srgrimes l = read(s, (char *)&m_rtmsg, sizeof(m_rtmsg)); 7451553Srgrimes } while (l > 0 && (rtm->rtm_seq != seq || rtm->rtm_pid != pid)); 7461553Srgrimes if (l < 0) 74729060Scharnier warn("read from routing socket"); 748147172Sru return (rtm); 7491553Srgrimes} 7501553Srgrimes 75113977Sphk/* 75213977Sphk * get_ether_addr - get the hardware address of an interface on the 75313977Sphk * the same subnet as ipaddr. 75413977Sphk */ 75513977Sphk#define MAX_IFS 32 75613977Sphk 757128181Sluigistatic int 758147172Sruget_ether_addr(in_addr_t ipaddr, struct ether_addr *hwaddr) 75913977Sphk{ 76013977Sphk struct ifreq *ifr, *ifend, *ifp; 761147172Sru in_addr_t ina, mask; 76213977Sphk struct sockaddr_dl *dla; 76313977Sphk struct ifreq ifreq; 76413977Sphk struct ifconf ifc; 76513977Sphk struct ifreq ifs[MAX_IFS]; 76687598Smikeh int sock; 767128192Sluigi int retval = 0; 76813977Sphk 76987598Smikeh sock = socket(AF_INET, SOCK_DGRAM, 0); 77087598Smikeh if (sock < 0) 77129060Scharnier err(1, "socket"); 77213977Sphk 77313977Sphk ifc.ifc_len = sizeof(ifs); 77413977Sphk ifc.ifc_req = ifs; 77592735Smikeh if (ioctl(sock, SIOCGIFCONF, &ifc) < 0) { 77629060Scharnier warnx("ioctl(SIOCGIFCONF)"); 777128192Sluigi goto done; 77813977Sphk } 77913977Sphk 780128192Sluigi#define NEXTIFR(i) \ 781128192Sluigi ((struct ifreq *)((char *)&(i)->ifr_addr \ 782128192Sluigi + MAX((i)->ifr_addr.sa_len, sizeof((i)->ifr_addr))) ) 783128192Sluigi 78413977Sphk /* 785128192Sluigi * Scan through looking for an interface with an Internet 786128192Sluigi * address on the same subnet as `ipaddr'. 787128192Sluigi */ 788128192Sluigi ifend = (struct ifreq *)(ifc.ifc_buf + ifc.ifc_len); 789128192Sluigi for (ifr = ifc.ifc_req; ifr < ifend; ifr = NEXTIFR(ifr) ) { 790128192Sluigi if (ifr->ifr_addr.sa_family != AF_INET) 791128192Sluigi continue; 792128192Sluigi strncpy(ifreq.ifr_name, ifr->ifr_name, 793128192Sluigi sizeof(ifreq.ifr_name)); 794163305Sglebius ifreq.ifr_addr = ifr->ifr_addr; 795128192Sluigi /* 796128192Sluigi * Check that the interface is up, 797128192Sluigi * and not point-to-point or loopback. 798128192Sluigi */ 799128192Sluigi if (ioctl(sock, SIOCGIFFLAGS, &ifreq) < 0) 800128192Sluigi continue; 801128192Sluigi if ((ifreq.ifr_flags & 802128192Sluigi (IFF_UP|IFF_BROADCAST|IFF_POINTOPOINT| 803128192Sluigi IFF_LOOPBACK|IFF_NOARP)) 804128192Sluigi != (IFF_UP|IFF_BROADCAST)) 805128192Sluigi continue; 806128192Sluigi /* 807128192Sluigi * Get its netmask and check that it's on 808128192Sluigi * the right subnet. 809128192Sluigi */ 810128192Sluigi if (ioctl(sock, SIOCGIFNETMASK, &ifreq) < 0) 811128192Sluigi continue; 812128192Sluigi mask = ((struct sockaddr_in *) 813128192Sluigi &ifreq.ifr_addr)->sin_addr.s_addr; 814128192Sluigi ina = ((struct sockaddr_in *) 815128192Sluigi &ifr->ifr_addr)->sin_addr.s_addr; 816128192Sluigi if ((ipaddr & mask) == (ina & mask)) 817128192Sluigi break; /* ok, we got it! */ 81813977Sphk } 81913977Sphk 820128192Sluigi if (ifr >= ifend) 821128192Sluigi goto done; 82213977Sphk 82313977Sphk /* 824128192Sluigi * Now scan through again looking for a link-level address 825128192Sluigi * for this interface. 826128192Sluigi */ 82713977Sphk ifp = ifr; 828128192Sluigi for (ifr = ifc.ifc_req; ifr < ifend; ifr = NEXTIFR(ifr)) 829128192Sluigi if (strcmp(ifp->ifr_name, ifr->ifr_name) == 0 && 830128192Sluigi ifr->ifr_addr.sa_family == AF_LINK) 831128192Sluigi break; 832128192Sluigi if (ifr >= ifend) 833128192Sluigi goto done; 834128192Sluigi /* 835128192Sluigi * Found the link-level address - copy it out 836128192Sluigi */ 837128192Sluigi dla = (struct sockaddr_dl *) &ifr->ifr_addr; 838128192Sluigi memcpy(hwaddr, LLADDR(dla), dla->sdl_alen); 839128192Sluigi printf("using interface %s for proxy with address ", 840128192Sluigi ifp->ifr_name); 841128192Sluigi printf("%s\n", ether_ntoa(hwaddr)); 842128192Sluigi retval = dla->sdl_alen; 843128192Sluigidone: 844128192Sluigi close(sock); 845147172Sru return (retval); 84613977Sphk} 847