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: releng/11.0/usr.sbin/arp/arp.c 288297 2015-09-27 04:54:29Z melifaro $"); 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, 84246143Sglebius struct sockaddr_in *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 90246143Sglebiusstatic int delete(char *host); 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, 96246143Sglebius struct sockaddr_in *dst, struct sockaddr_dl *sdl); 97147172Srustatic int get_ether_addr(in_addr_t ipaddr, struct ether_addr *hwaddr); 98246143Sglebiusstatic struct sockaddr_in *getaddr(char *host); 99147172Srustatic int valid_type(int type); 100128181Sluigi 10131145Sjulianstatic int nflag; /* no reverse dns lookups */ 102117729Syarstatic char *rifname; 1031553Srgrimes 104203919Srustatic time_t expire_time; 105246143Sglebiusstatic int flags, doing_proxy; 106128192Sluigi 107264174Sgnnstruct if_nameindex *ifnameindex; 108264174Sgnn 10931145Sjulian/* which function we're supposed to do */ 11031145Sjulian#define F_GET 1 11131145Sjulian#define F_SET 2 11231145Sjulian#define F_FILESET 3 11331145Sjulian#define F_REPLACE 4 11431145Sjulian#define F_DELETE 5 11531145Sjulian 11631145Sjulian#define SETFUNC(f) { if (func) usage(); func = (f); } 11731145Sjulian 11813977Sphkint 11977870Srumain(int argc, char *argv[]) 1201553Srgrimes{ 12131145Sjulian int ch, func = 0; 12231145Sjulian int rtn = 0; 123128181Sluigi int aflag = 0; /* do it for all entries */ 1241553Srgrimes 125117729Syar while ((ch = getopt(argc, argv, "andfsSi:")) != -1) 126196216Sremko switch(ch) { 1271553Srgrimes case 'a': 12831145Sjulian aflag = 1; 12931145Sjulian break; 1301553Srgrimes case 'd': 13131145Sjulian SETFUNC(F_DELETE); 13231145Sjulian break; 1331553Srgrimes case 'n': 1341553Srgrimes nflag = 1; 13531145Sjulian break; 13613977Sphk case 'S': 13731145Sjulian SETFUNC(F_REPLACE); 13831145Sjulian break; 1391553Srgrimes case 's': 14031145Sjulian SETFUNC(F_SET); 14131145Sjulian break; 1429874Sjkh case 'f' : 14331145Sjulian SETFUNC(F_FILESET); 14431145Sjulian break; 145117729Syar case 'i': 146117729Syar rifname = optarg; 147117729Syar break; 1481553Srgrimes case '?': 1491553Srgrimes default: 1501553Srgrimes usage(); 1511553Srgrimes } 15231145Sjulian argc -= optind; 15331145Sjulian argv += optind; 15431145Sjulian 15531145Sjulian if (!func) 15631145Sjulian func = F_GET; 157117729Syar if (rifname) { 158154162Sbrooks if (func != F_GET && !(func == F_DELETE && aflag)) 159117729Syar errx(1, "-i not applicable to this operation"); 160117729Syar if (if_nametoindex(rifname) == 0) { 161117729Syar if (errno == ENXIO) 162117729Syar errx(1, "interface %s does not exist", rifname); 163117729Syar else 164117729Syar err(1, "if_nametoindex(%s)", rifname); 165117729Syar } 166117729Syar } 16731145Sjulian switch (func) { 16831145Sjulian case F_GET: 16931145Sjulian if (aflag) { 17031145Sjulian if (argc != 0) 17131145Sjulian usage(); 17231145Sjulian search(0, print_entry); 17331145Sjulian } else { 17431145Sjulian if (argc != 1) 17531145Sjulian usage(); 176147172Sru rtn = get(argv[0]); 17731145Sjulian } 17831145Sjulian break; 17931145Sjulian case F_SET: 18031145Sjulian case F_REPLACE: 18177870Sru if (argc < 2 || argc > 6) 18231145Sjulian usage(); 18331145Sjulian if (func == F_REPLACE) 184246143Sglebius (void)delete(argv[0]); 18531145Sjulian rtn = set(argc, argv) ? 1 : 0; 18631145Sjulian break; 18731145Sjulian case F_DELETE: 18831145Sjulian if (aflag) { 18931145Sjulian if (argc != 0) 19031145Sjulian usage(); 19131145Sjulian search(0, nuke_entry); 192255821Sglebius } else { 193255821Sglebius if (argc != 1) 194255821Sglebius usage(); 195246143Sglebius rtn = delete(argv[0]); 196255821Sglebius } 19731145Sjulian break; 19831145Sjulian case F_FILESET: 19931145Sjulian if (argc != 1) 20031145Sjulian usage(); 20131145Sjulian rtn = file(argv[0]); 20231145Sjulian break; 20331145Sjulian } 20431145Sjulian 205264174Sgnn if (ifnameindex != NULL) 206264174Sgnn if_freenameindex(ifnameindex); 207264174Sgnn 208147172Sru return (rtn); 2091553Srgrimes} 2101553Srgrimes 2111553Srgrimes/* 2121553Srgrimes * Process a file to set standard arp entries 2131553Srgrimes */ 214128181Sluigistatic int 21513977Sphkfile(char *name) 2161553Srgrimes{ 2171553Srgrimes FILE *fp; 2181553Srgrimes int i, retval; 219109413Sru char line[100], arg[5][50], *args[5], *p; 2201553Srgrimes 22129060Scharnier if ((fp = fopen(name, "r")) == NULL) 222128054Smux err(1, "cannot open %s", name); 2231553Srgrimes args[0] = &arg[0][0]; 2241553Srgrimes args[1] = &arg[1][0]; 2251553Srgrimes args[2] = &arg[2][0]; 2261553Srgrimes args[3] = &arg[3][0]; 2271553Srgrimes args[4] = &arg[4][0]; 2281553Srgrimes retval = 0; 229167260Skevlo while(fgets(line, sizeof(line), fp) != NULL) { 230109413Sru if ((p = strchr(line, '#')) != NULL) 231109413Sru *p = '\0'; 232109413Sru for (p = line; isblank(*p); p++); 233111910Sru if (*p == '\n' || *p == '\0') 234108314Sru continue; 235109413Sru i = sscanf(p, "%49s %49s %49s %49s %49s", arg[0], arg[1], 23656134Sjkh arg[2], arg[3], arg[4]); 2371553Srgrimes if (i < 2) { 23829060Scharnier warnx("bad line: %s", line); 2391553Srgrimes retval = 1; 2401553Srgrimes continue; 2411553Srgrimes } 2421553Srgrimes if (set(i, args)) 2431553Srgrimes retval = 1; 2441553Srgrimes } 2451553Srgrimes fclose(fp); 2461553Srgrimes return (retval); 2471553Srgrimes} 2481553Srgrimes 2491553Srgrimes/* 250246143Sglebius * Given a hostname, fills up a (static) struct sockaddr_in with 251128192Sluigi * the address of the host and returns a pointer to the 252128192Sluigi * structure. 253128192Sluigi */ 254246143Sglebiusstatic struct sockaddr_in * 255128192Sluigigetaddr(char *host) 256128192Sluigi{ 257128192Sluigi struct hostent *hp; 258246143Sglebius static struct sockaddr_in reply; 259128192Sluigi 260128192Sluigi bzero(&reply, sizeof(reply)); 261128192Sluigi reply.sin_len = sizeof(reply); 262128192Sluigi reply.sin_family = AF_INET; 263128192Sluigi reply.sin_addr.s_addr = inet_addr(host); 264128192Sluigi if (reply.sin_addr.s_addr == INADDR_NONE) { 265128192Sluigi if (!(hp = gethostbyname(host))) { 266128192Sluigi warnx("%s: %s", host, hstrerror(h_errno)); 267147172Sru return (NULL); 268128192Sluigi } 269128192Sluigi bcopy((char *)hp->h_addr, (char *)&reply.sin_addr, 270128192Sluigi sizeof reply.sin_addr); 271128192Sluigi } 272147172Sru return (&reply); 273128192Sluigi} 274128192Sluigi 275128192Sluigi/* 276147172Sru * Returns true if the type is a valid one for ARP. 277128192Sluigi */ 278128192Sluigistatic int 279128192Sluigivalid_type(int type) 280128192Sluigi{ 281147172Sru 282128192Sluigi switch (type) { 283128192Sluigi case IFT_ETHER: 284128192Sluigi case IFT_FDDI: 285280998Smarkj case IFT_INFINIBAND: 286128192Sluigi case IFT_ISO88023: 287128192Sluigi case IFT_ISO88024: 288128192Sluigi case IFT_ISO88025: 289128192Sluigi case IFT_L2VLAN: 290151989Sthompsa case IFT_BRIDGE: 291147172Sru return (1); 292147172Sru default: 293147172Sru return (0); 294128192Sluigi } 295128192Sluigi} 296128192Sluigi 297128192Sluigi/* 2988857Srgrimes * Set an individual arp entry 2991553Srgrimes */ 300128192Sluigistatic int 30113977Sphkset(int argc, char **argv) 3021553Srgrimes{ 303246143Sglebius struct sockaddr_in *addr; 304246143Sglebius struct sockaddr_in *dst; /* what are we looking for */ 305128054Smux struct sockaddr_dl *sdl; 306128181Sluigi struct rt_msghdr *rtm; 30793952Sru struct ether_addr *ea; 3081553Srgrimes char *host = argv[0], *eaddr = argv[1]; 309147172Sru struct sockaddr_dl sdl_m; 3101553Srgrimes 3111553Srgrimes argc -= 2; 3121553Srgrimes argv += 2; 313128181Sluigi 314128181Sluigi bzero(&sdl_m, sizeof(sdl_m)); 315128181Sluigi sdl_m.sdl_len = sizeof(sdl_m); 316128181Sluigi sdl_m.sdl_family = AF_LINK; 317128181Sluigi 318128192Sluigi dst = getaddr(host); 319128192Sluigi if (dst == NULL) 320128192Sluigi return (1); 321246143Sglebius doing_proxy = flags = expire_time = 0; 3221553Srgrimes while (argc-- > 0) { 3231553Srgrimes if (strncmp(argv[0], "temp", 4) == 0) { 324216076Sglebius struct timespec tp; 325216078Sglebius int max_age; 326216078Sglebius size_t len = sizeof(max_age); 327216078Sglebius 328216076Sglebius clock_gettime(CLOCK_MONOTONIC, &tp); 329216078Sglebius if (sysctlbyname("net.link.ether.inet.max_age", 330216078Sglebius &max_age, &len, NULL, 0) != 0) 331216078Sglebius err(1, "sysctlbyname"); 332216078Sglebius expire_time = tp.tv_sec + max_age; 333177362Ssam } else if (strncmp(argv[0], "pub", 3) == 0) { 3341553Srgrimes flags |= RTF_ANNOUNCE; 33577870Sru doing_proxy = 1; 33677870Sru if (argc && strncmp(argv[1], "only", 3) == 0) { 337246143Sglebius /* 338246143Sglebius * Compatibility: in pre FreeBSD 8 times 339246143Sglebius * the "only" keyword used to mean that 340246143Sglebius * an ARP entry should be announced, but 341246143Sglebius * not installed into routing table. 342246143Sglebius */ 34377870Sru argc--; argv++; 34477870Sru } 345177362Ssam } else if (strncmp(argv[0], "blackhole", 9) == 0) { 346186485Strhodes if (flags & RTF_REJECT) { 347186485Strhodes printf("Choose one of blackhole or reject, not both.\n"); 348186485Strhodes } 349177362Ssam flags |= RTF_BLACKHOLE; 350177362Ssam } else if (strncmp(argv[0], "reject", 6) == 0) { 351186485Strhodes if (flags & RTF_BLACKHOLE) { 352186485Strhodes printf("Choose one of blackhole or reject, not both.\n"); 353186485Strhodes } 354177362Ssam flags |= RTF_REJECT; 3551553Srgrimes } else if (strncmp(argv[0], "trail", 5) == 0) { 356128192Sluigi /* XXX deprecated and undocumented feature */ 3571553Srgrimes printf("%s: Sending trailers is no longer supported\n", 3581553Srgrimes host); 3591553Srgrimes } 3601553Srgrimes argv++; 3611553Srgrimes } 36293952Sru ea = (struct ether_addr *)LLADDR(&sdl_m); 36313977Sphk if (doing_proxy && !strcmp(eaddr, "auto")) { 364128192Sluigi if (!get_ether_addr(dst->sin_addr.s_addr, ea)) { 36573135Sru printf("no interface found for %s\n", 366128192Sluigi inet_ntoa(dst->sin_addr)); 36713977Sphk return (1); 36813977Sphk } 36993952Sru sdl_m.sdl_alen = ETHER_ADDR_LEN; 37013977Sphk } else { 371128192Sluigi struct ether_addr *ea1 = ether_aton(eaddr); 372128192Sluigi 373155471Sglebius if (ea1 == NULL) { 374128192Sluigi warnx("invalid Ethernet address '%s'", eaddr); 375155471Sglebius return (1); 376155471Sglebius } else { 377128192Sluigi *ea = *ea1; 37893952Sru sdl_m.sdl_alen = ETHER_ADDR_LEN; 379128192Sluigi } 38013977Sphk } 381201282Sqingli 382201282Sqingli /* 383201282Sqingli * In the case a proxy-arp entry is being added for 384201282Sqingli * a remote end point, the RTF_ANNOUNCE flag in the 385201282Sqingli * RTM_GET command is an indication to the kernel 386201282Sqingli * routing code that the interface associated with 387201282Sqingli * the prefix route covering the local end of the 388201282Sqingli * PPP link should be returned, on which ARP applies. 389201282Sqingli */ 390201282Sqingli rtm = rtmsg(RTM_GET, dst, &sdl_m); 391201282Sqingli if (rtm == NULL) { 392201282Sqingli warn("%s", host); 393201282Sqingli return (1); 3941553Srgrimes } 395246143Sglebius addr = (struct sockaddr_in *)(rtm + 1); 396201282Sqingli sdl = (struct sockaddr_dl *)(SA_SIZE(addr) + (char *)addr); 397128192Sluigi 398201282Sqingli if ((sdl->sdl_family != AF_LINK) || 399201282Sqingli (rtm->rtm_flags & RTF_GATEWAY) || 400201282Sqingli !valid_type(sdl->sdl_type)) { 4011553Srgrimes printf("cannot intuit interface index and type for %s\n", host); 4021553Srgrimes return (1); 4031553Srgrimes } 4041553Srgrimes sdl_m.sdl_type = sdl->sdl_type; 4051553Srgrimes sdl_m.sdl_index = sdl->sdl_index; 406147170Sglebius return (rtmsg(RTM_ADD, dst, &sdl_m) == NULL); 4071553Srgrimes} 4081553Srgrimes 4091553Srgrimes/* 4101553Srgrimes * Display an individual arp entry 4111553Srgrimes */ 412147172Srustatic int 41313977Sphkget(char *host) 4141553Srgrimes{ 415246143Sglebius struct sockaddr_in *addr; 4161553Srgrimes 417128192Sluigi addr = getaddr(host); 418128192Sluigi if (addr == NULL) 419147172Sru return (1); 420128181Sluigi if (0 == search(addr->sin_addr.s_addr, print_entry)) { 421117729Syar printf("%s (%s) -- no entry", 42287598Smikeh host, inet_ntoa(addr->sin_addr)); 423117729Syar if (rifname) 424117729Syar printf(" on %s", rifname); 425117729Syar printf("\n"); 426147172Sru return (1); 4271553Srgrimes } 428147172Sru return (0); 4291553Srgrimes} 4301553Srgrimes 4311553Srgrimes/* 4328857Srgrimes * Delete an arp entry 4331553Srgrimes */ 434128181Sluigistatic int 435246143Sglebiusdelete(char *host) 4361553Srgrimes{ 437246143Sglebius struct sockaddr_in *addr, *dst; 438128181Sluigi struct rt_msghdr *rtm; 4391553Srgrimes struct sockaddr_dl *sdl; 440186119Sqingli struct sockaddr_dl sdl_m; 4411553Srgrimes 442128192Sluigi dst = getaddr(host); 443128192Sluigi if (dst == NULL) 444147172Sru return (1); 445186119Sqingli 446186119Sqingli /* 447201282Sqingli * Perform a regular entry delete first. 448201282Sqingli */ 449201282Sqingli flags &= ~RTF_ANNOUNCE; 450201282Sqingli 451201282Sqingli /* 452186119Sqingli * setup the data structure to notify the kernel 453186119Sqingli * it is the ARP entry the RTM_GET is interested 454186119Sqingli * in 455186119Sqingli */ 456186119Sqingli bzero(&sdl_m, sizeof(sdl_m)); 457186119Sqingli sdl_m.sdl_len = sizeof(sdl_m); 458186119Sqingli sdl_m.sdl_family = AF_LINK; 459186119Sqingli 460128192Sluigi for (;;) { /* try twice */ 461186119Sqingli rtm = rtmsg(RTM_GET, dst, &sdl_m); 462128192Sluigi if (rtm == NULL) { 463128192Sluigi warn("%s", host); 4641553Srgrimes return (1); 4651553Srgrimes } 466246143Sglebius addr = (struct sockaddr_in *)(rtm + 1); 467128192Sluigi sdl = (struct sockaddr_dl *)(SA_SIZE(addr) + (char *)addr); 468186119Sqingli 469186119Sqingli /* 470186119Sqingli * With the new L2/L3 restructure, the route 471186119Sqingli * returned is a prefix route. The important 472186119Sqingli * piece of information from the previous 473186119Sqingli * RTM_GET is the interface index. In the 474186119Sqingli * case of ECMP, the kernel will traverse 475186119Sqingli * the route group for the given entry. 476186119Sqingli */ 477186119Sqingli if (sdl->sdl_family == AF_LINK && 478128192Sluigi !(rtm->rtm_flags & RTF_GATEWAY) && 479186119Sqingli valid_type(sdl->sdl_type) ) { 480186119Sqingli addr->sin_addr.s_addr = dst->sin_addr.s_addr; 481186119Sqingli break; 482186119Sqingli } 483186119Sqingli 484201282Sqingli /* 485201282Sqingli * Regualar entry delete failed, now check if there 486201282Sqingli * is a proxy-arp entry to remove. 487201282Sqingli */ 488201282Sqingli if (flags & RTF_ANNOUNCE) { 489128192Sluigi fprintf(stderr, "delete: cannot locate %s\n",host); 490128192Sluigi return (1); 491128192Sluigi } 492201282Sqingli 493201282Sqingli flags |= RTF_ANNOUNCE; 4941553Srgrimes } 495186500Sqingli rtm->rtm_flags |= RTF_LLDATA; 496128192Sluigi if (rtmsg(RTM_DELETE, dst, NULL) != NULL) { 49787598Smikeh printf("%s (%s) deleted\n", host, inet_ntoa(addr->sin_addr)); 49813977Sphk return (0); 49913977Sphk } 50013977Sphk return (1); 5011553Srgrimes} 5021553Srgrimes 503201282Sqingli 5041553Srgrimes/* 50531145Sjulian * Search the arp table and do some action on matching entries 5061553Srgrimes */ 507128181Sluigistatic int 508128181Sluigisearch(u_long addr, action_fn *action) 5091553Srgrimes{ 5101553Srgrimes int mib[6]; 5111553Srgrimes size_t needed; 512201202Sjhb char *lim, *buf, *next; 5131553Srgrimes struct rt_msghdr *rtm; 514246143Sglebius struct sockaddr_in *sin2; 5151553Srgrimes struct sockaddr_dl *sdl; 516117729Syar char ifname[IF_NAMESIZE]; 517140735Smaxim int st, found_entry = 0; 5181553Srgrimes 5191553Srgrimes mib[0] = CTL_NET; 5201553Srgrimes mib[1] = PF_ROUTE; 5211553Srgrimes mib[2] = 0; 5221553Srgrimes mib[3] = AF_INET; 5231553Srgrimes mib[4] = NET_RT_FLAGS; 524186119Sqingli#ifdef RTF_LLINFO 5251553Srgrimes mib[5] = RTF_LLINFO; 526186119Sqingli#else 527186119Sqingli mib[5] = 0; 528186119Sqingli#endif 5291553Srgrimes if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0) 530128054Smux err(1, "route-sysctl-estimate"); 531128192Sluigi if (needed == 0) /* empty table */ 532128181Sluigi return 0; 533140735Smaxim buf = NULL; 534140748Smaxim for (;;) { 535201202Sjhb buf = reallocf(buf, needed); 536201202Sjhb if (buf == NULL) 537140735Smaxim errx(1, "could not reallocate memory"); 538140735Smaxim st = sysctl(mib, 6, buf, &needed, NULL, 0); 539140748Smaxim if (st == 0 || errno != ENOMEM) 540140748Smaxim break; 541140748Smaxim needed += needed / 8; 542140748Smaxim } 543140735Smaxim if (st == -1) 544128054Smux err(1, "actual retrieval of routing table"); 5451553Srgrimes lim = buf + needed; 5461553Srgrimes for (next = buf; next < lim; next += rtm->rtm_msglen) { 5471553Srgrimes rtm = (struct rt_msghdr *)next; 548246143Sglebius sin2 = (struct sockaddr_in *)(rtm + 1); 549130246Sstefanf sdl = (struct sockaddr_dl *)((char *)sin2 + SA_SIZE(sin2)); 550117729Syar if (rifname && if_indextoname(sdl->sdl_index, ifname) && 551117729Syar strcmp(ifname, rifname)) 552117729Syar continue; 5531553Srgrimes if (addr) { 55487598Smikeh if (addr != sin2->sin_addr.s_addr) 5551553Srgrimes continue; 5561553Srgrimes found_entry = 1; 5571553Srgrimes } 55887598Smikeh (*action)(sdl, sin2, rtm); 5591553Srgrimes } 56076216Syar free(buf); 561147172Sru return (found_entry); 5621553Srgrimes} 5631553Srgrimes 56431145Sjulian/* 56531145Sjulian * Display an arp entry 56631145Sjulian */ 567209063Smlaier 568128181Sluigistatic void 56931145Sjulianprint_entry(struct sockaddr_dl *sdl, 570246143Sglebius struct sockaddr_in *addr, struct rt_msghdr *rtm) 57131145Sjulian{ 57277870Sru const char *host; 57331145Sjulian struct hostent *hp; 57496202Skbyanc struct iso88025_sockaddr_dl_data *trld; 575264174Sgnn struct if_nameindex *p; 57644627Sjulian int seg; 57731145Sjulian 578264174Sgnn if (ifnameindex == NULL) 579264174Sgnn if ((ifnameindex = if_nameindex()) == NULL) 580264174Sgnn err(1, "cannot retrieve interface names"); 581264174Sgnn 58231145Sjulian if (nflag == 0) 58387598Smikeh hp = gethostbyaddr((caddr_t)&(addr->sin_addr), 58487598Smikeh sizeof addr->sin_addr, AF_INET); 58531145Sjulian else 58631145Sjulian hp = 0; 58731145Sjulian if (hp) 58831145Sjulian host = hp->h_name; 58931145Sjulian else { 59031145Sjulian host = "?"; 59131145Sjulian if (h_errno == TRY_AGAIN) 59231145Sjulian nflag = 1; 59331145Sjulian } 59487598Smikeh printf("%s (%s) at ", host, inet_ntoa(addr->sin_addr)); 595130408Sdfr if (sdl->sdl_alen) { 596139270Sru if ((sdl->sdl_type == IFT_ETHER || 597151989Sthompsa sdl->sdl_type == IFT_L2VLAN || 598151989Sthompsa sdl->sdl_type == IFT_BRIDGE) && 599130408Sdfr sdl->sdl_alen == ETHER_ADDR_LEN) 600130408Sdfr printf("%s", ether_ntoa((struct ether_addr *)LLADDR(sdl))); 601130408Sdfr else { 602130408Sdfr int n = sdl->sdl_nlen > 0 ? sdl->sdl_nlen + 1 : 0; 603130408Sdfr 604130408Sdfr printf("%s", link_ntoa(sdl) + n); 605130408Sdfr } 606130408Sdfr } else 60731145Sjulian printf("(incomplete)"); 608264174Sgnn 609264174Sgnn for (p = ifnameindex; p && ifnameindex->if_index && 610264174Sgnn ifnameindex->if_name; p++) { 611264174Sgnn if (p->if_index == sdl->sdl_index) { 612264174Sgnn printf(" on %s", p->if_name); 613264174Sgnn break; 614264174Sgnn } 615264174Sgnn } 616264174Sgnn 61731145Sjulian if (rtm->rtm_rmx.rmx_expire == 0) 61831145Sjulian printf(" permanent"); 619203919Sru else { 620216075Sglebius static struct timespec tp; 621216075Sglebius if (tp.tv_sec == 0) 622216075Sglebius clock_gettime(CLOCK_MONOTONIC, &tp); 623216075Sglebius if ((expire_time = rtm->rtm_rmx.rmx_expire - tp.tv_sec) > 0) 624203919Sru printf(" expires in %d seconds", (int)expire_time); 625203919Sru else 626203919Sru printf(" expired"); 627203919Sru } 628186119Sqingli if (rtm->rtm_flags & RTF_ANNOUNCE) 629186119Sqingli printf(" published"); 630186119Sqingli switch(sdl->sdl_type) { 631128181Sluigi case IFT_ETHER: 63244627Sjulian printf(" [ethernet]"); 63344627Sjulian break; 634128181Sluigi case IFT_ISO88025: 63544627Sjulian printf(" [token-ring]"); 63696202Skbyanc trld = SDL_ISO88025(sdl); 63796202Skbyanc if (trld->trld_rcf != 0) { 63896202Skbyanc printf(" rt=%x", ntohs(trld->trld_rcf)); 63996202Skbyanc for (seg = 0; 64096202Skbyanc seg < ((TR_RCF_RIFLEN(trld->trld_rcf) - 2 ) / 2); 64196202Skbyanc seg++) 64296235Swpaul printf(":%x", ntohs(*(trld->trld_route[seg]))); 64396202Skbyanc } 64444627Sjulian break; 645128181Sluigi case IFT_FDDI: 64685123Smdodd printf(" [fddi]"); 64785123Smdodd break; 648128181Sluigi case IFT_ATM: 64985123Smdodd printf(" [atm]"); 65085123Smdodd break; 651128181Sluigi case IFT_L2VLAN: 65275180Syar printf(" [vlan]"); 65375180Syar break; 654130408Sdfr case IFT_IEEE1394: 655130408Sdfr printf(" [firewire]"); 656130408Sdfr break; 657151989Sthompsa case IFT_BRIDGE: 658151989Sthompsa printf(" [bridge]"); 659151989Sthompsa break; 660280998Smarkj case IFT_INFINIBAND: 661280998Smarkj printf(" [infiniband]"); 662280998Smarkj break; 663128181Sluigi default: 66494075Smurray break; 66544627Sjulian } 66644627Sjulian 66731145Sjulian printf("\n"); 66844627Sjulian 66931145Sjulian} 67031145Sjulian 67131145Sjulian/* 67231145Sjulian * Nuke an arp entry 67331145Sjulian */ 674128181Sluigistatic void 67587598Smikehnuke_entry(struct sockaddr_dl *sdl __unused, 676288297Smelifaro struct sockaddr_in *addr, struct rt_msghdr *rtm) 67731145Sjulian{ 67831145Sjulian char ip[20]; 67931145Sjulian 680288297Smelifaro if (rtm->rtm_flags & RTF_PINNED) 681288297Smelifaro return; 682288297Smelifaro 68387598Smikeh snprintf(ip, sizeof(ip), "%s", inet_ntoa(addr->sin_addr)); 684246143Sglebius delete(ip); 68531145Sjulian} 68631145Sjulian 687128181Sluigistatic void 68813977Sphkusage(void) 6891553Srgrimes{ 69031145Sjulian fprintf(stderr, "%s\n%s\n%s\n%s\n%s\n%s\n%s\n", 691117729Syar "usage: arp [-n] [-i interface] hostname", 692117729Syar " arp [-n] [-i interface] -a", 69377870Sru " arp -d hostname [pub]", 694154191Sbrooks " arp -d [-i interface] -a", 695186485Strhodes " arp -s hostname ether_addr [temp] [reject | blackhole] [pub [only]]", 696186485Strhodes " arp -S hostname ether_addr [temp] [reject | blackhole] [pub [only]]", 69729060Scharnier " arp -f filename"); 6981553Srgrimes exit(1); 6991553Srgrimes} 7001553Srgrimes 701128181Sluigistatic struct rt_msghdr * 702246143Sglebiusrtmsg(int cmd, struct sockaddr_in *dst, struct sockaddr_dl *sdl) 7031553Srgrimes{ 7041553Srgrimes static int seq; 7051553Srgrimes int rlen; 706128181Sluigi int l; 707175206Ssam struct sockaddr_in so_mask, *som = &so_mask; 708128181Sluigi static int s = -1; 709128181Sluigi static pid_t pid; 710128181Sluigi 711128181Sluigi static struct { 712128181Sluigi struct rt_msghdr m_rtm; 713128181Sluigi char m_space[512]; 714128181Sluigi } m_rtmsg; 715128181Sluigi 716128054Smux struct rt_msghdr *rtm = &m_rtmsg.m_rtm; 717128054Smux char *cp = m_rtmsg.m_space; 7181553Srgrimes 719128181Sluigi if (s < 0) { /* first time: open socket, get pid */ 720128181Sluigi s = socket(PF_ROUTE, SOCK_RAW, 0); 721128181Sluigi if (s < 0) 722128181Sluigi err(1, "socket"); 723128181Sluigi pid = getpid(); 724128181Sluigi } 725128181Sluigi bzero(&so_mask, sizeof(so_mask)); 726128181Sluigi so_mask.sin_len = 8; 727128181Sluigi so_mask.sin_addr.s_addr = 0xffffffff; 728128181Sluigi 7291553Srgrimes errno = 0; 730128192Sluigi /* 731128192Sluigi * XXX RTM_DELETE relies on a previous RTM_GET to fill the buffer 732128192Sluigi * appropriately. 733128192Sluigi */ 7341553Srgrimes if (cmd == RTM_DELETE) 7351553Srgrimes goto doit; 7361553Srgrimes bzero((char *)&m_rtmsg, sizeof(m_rtmsg)); 7371553Srgrimes rtm->rtm_flags = flags; 7381553Srgrimes rtm->rtm_version = RTM_VERSION; 7391553Srgrimes 7401553Srgrimes switch (cmd) { 7411553Srgrimes default: 74229060Scharnier errx(1, "internal wrong cmd"); 7431553Srgrimes case RTM_ADD: 7441553Srgrimes rtm->rtm_addrs |= RTA_GATEWAY; 7451553Srgrimes rtm->rtm_rmx.rmx_expire = expire_time; 7461553Srgrimes rtm->rtm_inits = RTV_EXPIRE; 747186500Sqingli rtm->rtm_flags |= (RTF_HOST | RTF_STATIC | RTF_LLDATA); 7481553Srgrimes if (doing_proxy) { 749246143Sglebius rtm->rtm_addrs |= RTA_NETMASK; 750246143Sglebius rtm->rtm_flags &= ~RTF_HOST; 7511553Srgrimes } 7521553Srgrimes /* FALLTHROUGH */ 7531553Srgrimes case RTM_GET: 7541553Srgrimes rtm->rtm_addrs |= RTA_DST; 7551553Srgrimes } 756193976Sdes#define NEXTADDR(w, s) \ 757193976Sdes do { \ 758193976Sdes if ((s) != NULL && rtm->rtm_addrs & (w)) { \ 759193976Sdes bcopy((s), cp, sizeof(*(s))); \ 760193976Sdes cp += SA_SIZE(s); \ 761193976Sdes } \ 762193976Sdes } while (0) 7631553Srgrimes 764128192Sluigi NEXTADDR(RTA_DST, dst); 765128192Sluigi NEXTADDR(RTA_GATEWAY, sdl); 766175206Ssam NEXTADDR(RTA_NETMASK, som); 7671553Srgrimes 7681553Srgrimes rtm->rtm_msglen = cp - (char *)&m_rtmsg; 7691553Srgrimesdoit: 7701553Srgrimes l = rtm->rtm_msglen; 7711553Srgrimes rtm->rtm_seq = ++seq; 7721553Srgrimes rtm->rtm_type = cmd; 7731553Srgrimes if ((rlen = write(s, (char *)&m_rtmsg, l)) < 0) { 7741553Srgrimes if (errno != ESRCH || cmd != RTM_DELETE) { 77529060Scharnier warn("writing to routing socket"); 776147172Sru return (NULL); 7771553Srgrimes } 7781553Srgrimes } 7791553Srgrimes do { 7801553Srgrimes l = read(s, (char *)&m_rtmsg, sizeof(m_rtmsg)); 7811553Srgrimes } while (l > 0 && (rtm->rtm_seq != seq || rtm->rtm_pid != pid)); 7821553Srgrimes if (l < 0) 78329060Scharnier warn("read from routing socket"); 784147172Sru return (rtm); 7851553Srgrimes} 7861553Srgrimes 78713977Sphk/* 78813977Sphk * get_ether_addr - get the hardware address of an interface on the 78913977Sphk * the same subnet as ipaddr. 79013977Sphk */ 79113977Sphk#define MAX_IFS 32 79213977Sphk 793128181Sluigistatic int 794147172Sruget_ether_addr(in_addr_t ipaddr, struct ether_addr *hwaddr) 79513977Sphk{ 79613977Sphk struct ifreq *ifr, *ifend, *ifp; 797147172Sru in_addr_t ina, mask; 79813977Sphk struct sockaddr_dl *dla; 79913977Sphk struct ifreq ifreq; 80013977Sphk struct ifconf ifc; 80113977Sphk struct ifreq ifs[MAX_IFS]; 80287598Smikeh int sock; 803128192Sluigi int retval = 0; 80413977Sphk 80587598Smikeh sock = socket(AF_INET, SOCK_DGRAM, 0); 80687598Smikeh if (sock < 0) 80729060Scharnier err(1, "socket"); 80813977Sphk 80913977Sphk ifc.ifc_len = sizeof(ifs); 81013977Sphk ifc.ifc_req = ifs; 81192735Smikeh if (ioctl(sock, SIOCGIFCONF, &ifc) < 0) { 81229060Scharnier warnx("ioctl(SIOCGIFCONF)"); 813128192Sluigi goto done; 81413977Sphk } 81513977Sphk 816128192Sluigi#define NEXTIFR(i) \ 817128192Sluigi ((struct ifreq *)((char *)&(i)->ifr_addr \ 818128192Sluigi + MAX((i)->ifr_addr.sa_len, sizeof((i)->ifr_addr))) ) 819128192Sluigi 82013977Sphk /* 821128192Sluigi * Scan through looking for an interface with an Internet 822128192Sluigi * address on the same subnet as `ipaddr'. 823128192Sluigi */ 824128192Sluigi ifend = (struct ifreq *)(ifc.ifc_buf + ifc.ifc_len); 825128192Sluigi for (ifr = ifc.ifc_req; ifr < ifend; ifr = NEXTIFR(ifr) ) { 826128192Sluigi if (ifr->ifr_addr.sa_family != AF_INET) 827128192Sluigi continue; 828128192Sluigi strncpy(ifreq.ifr_name, ifr->ifr_name, 829128192Sluigi sizeof(ifreq.ifr_name)); 830163305Sglebius ifreq.ifr_addr = ifr->ifr_addr; 831128192Sluigi /* 832128192Sluigi * Check that the interface is up, 833128192Sluigi * and not point-to-point or loopback. 834128192Sluigi */ 835128192Sluigi if (ioctl(sock, SIOCGIFFLAGS, &ifreq) < 0) 836128192Sluigi continue; 837128192Sluigi if ((ifreq.ifr_flags & 838128192Sluigi (IFF_UP|IFF_BROADCAST|IFF_POINTOPOINT| 839128192Sluigi IFF_LOOPBACK|IFF_NOARP)) 840128192Sluigi != (IFF_UP|IFF_BROADCAST)) 841128192Sluigi continue; 842128192Sluigi /* 843128192Sluigi * Get its netmask and check that it's on 844128192Sluigi * the right subnet. 845128192Sluigi */ 846128192Sluigi if (ioctl(sock, SIOCGIFNETMASK, &ifreq) < 0) 847128192Sluigi continue; 848128192Sluigi mask = ((struct sockaddr_in *) 849128192Sluigi &ifreq.ifr_addr)->sin_addr.s_addr; 850128192Sluigi ina = ((struct sockaddr_in *) 851128192Sluigi &ifr->ifr_addr)->sin_addr.s_addr; 852128192Sluigi if ((ipaddr & mask) == (ina & mask)) 853128192Sluigi break; /* ok, we got it! */ 85413977Sphk } 85513977Sphk 856128192Sluigi if (ifr >= ifend) 857128192Sluigi goto done; 85813977Sphk 85913977Sphk /* 860128192Sluigi * Now scan through again looking for a link-level address 861128192Sluigi * for this interface. 862128192Sluigi */ 86313977Sphk ifp = ifr; 864128192Sluigi for (ifr = ifc.ifc_req; ifr < ifend; ifr = NEXTIFR(ifr)) 865128192Sluigi if (strcmp(ifp->ifr_name, ifr->ifr_name) == 0 && 866128192Sluigi ifr->ifr_addr.sa_family == AF_LINK) 867128192Sluigi break; 868128192Sluigi if (ifr >= ifend) 869128192Sluigi goto done; 870128192Sluigi /* 871128192Sluigi * Found the link-level address - copy it out 872128192Sluigi */ 873128192Sluigi dla = (struct sockaddr_dl *) &ifr->ifr_addr; 874128192Sluigi memcpy(hwaddr, LLADDR(dla), dla->sdl_alen); 875128192Sluigi printf("using interface %s for proxy with address ", 876128192Sluigi ifp->ifr_name); 877128192Sluigi printf("%s\n", ether_ntoa(hwaddr)); 878128192Sluigi retval = dla->sdl_alen; 879128192Sluigidone: 880128192Sluigi close(sock); 881147172Sru return (retval); 88213977Sphk} 883