arp.c revision 85123
11553Srgrimes/* 21553Srgrimes * Copyright (c) 1984, 1993 31553Srgrimes * The Regents of the University of California. All rights reserved. 41553Srgrimes * 51553Srgrimes * This code is derived from software contributed to Berkeley by 61553Srgrimes * Sun Microsystems, Inc. 71553Srgrimes * 81553Srgrimes * Redistribution and use in source and binary forms, with or without 91553Srgrimes * modification, are permitted provided that the following conditions 101553Srgrimes * are met: 111553Srgrimes * 1. Redistributions of source code must retain the above copyright 121553Srgrimes * notice, this list of conditions and the following disclaimer. 131553Srgrimes * 2. Redistributions in binary form must reproduce the above copyright 141553Srgrimes * notice, this list of conditions and the following disclaimer in the 151553Srgrimes * documentation and/or other materials provided with the distribution. 161553Srgrimes * 3. All advertising materials mentioning features or use of this software 171553Srgrimes * must display the following acknowledgement: 181553Srgrimes * This product includes software developed by the University of 191553Srgrimes * California, Berkeley and its contributors. 201553Srgrimes * 4. Neither the name of the University nor the names of its contributors 211553Srgrimes * may be used to endorse or promote products derived from this software 221553Srgrimes * without specific prior written permission. 231553Srgrimes * 241553Srgrimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 251553Srgrimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 261553Srgrimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 271553Srgrimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 281553Srgrimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 291553Srgrimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 301553Srgrimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 311553Srgrimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 321553Srgrimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 331553Srgrimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 341553Srgrimes * SUCH DAMAGE. 351553Srgrimes */ 361553Srgrimes 371553Srgrimes#ifndef lint 3813977Sphkstatic char const copyright[] = 391553Srgrimes"@(#) Copyright (c) 1984, 1993\n\ 401553Srgrimes The Regents of the University of California. All rights reserved.\n"; 411553Srgrimes#endif /* not lint */ 421553Srgrimes 431553Srgrimes#ifndef lint 4429060Scharnier#if 0 4513977Sphkstatic char const sccsid[] = "@(#)from: arp.c 8.2 (Berkeley) 1/2/94"; 4629060Scharnier#endif 4729060Scharnierstatic const char rcsid[] = 4850479Speter "$FreeBSD: head/usr.sbin/arp/arp.c 85123 2001-10-19 00:33:26Z mdodd $"; 491553Srgrimes#endif /* not lint */ 501553Srgrimes 511553Srgrimes/* 521553Srgrimes * arp - display, set, and delete arp table entries 531553Srgrimes */ 541553Srgrimes 551553Srgrimes 561553Srgrimes#include <sys/param.h> 571553Srgrimes#include <sys/file.h> 581553Srgrimes#include <sys/socket.h> 5913977Sphk#include <sys/sockio.h> 601553Srgrimes#include <sys/sysctl.h> 6113977Sphk#include <sys/ioctl.h> 6220287Swollman#include <sys/time.h> 631553Srgrimes 641553Srgrimes#include <net/if.h> 651553Srgrimes#include <net/if_dl.h> 661553Srgrimes#include <net/if_types.h> 671553Srgrimes#include <net/route.h> 681553Srgrimes 691553Srgrimes#include <netinet/in.h> 701553Srgrimes#include <netinet/if_ether.h> 711553Srgrimes 721553Srgrimes#include <arpa/inet.h> 731553Srgrimes 7429060Scharnier#include <err.h> 7529060Scharnier#include <errno.h> 761553Srgrimes#include <netdb.h> 771553Srgrimes#include <nlist.h> 7829060Scharnier#include <paths.h> 791553Srgrimes#include <stdio.h> 8013977Sphk#include <stdlib.h> 8129060Scharnier#include <strings.h> 8213977Sphk#include <unistd.h> 831553Srgrimes 8431145Sjulianvoid search(u_long addr, void (*action)(struct sockaddr_dl *sdl, 8531145Sjulian struct sockaddr_inarp *sin, struct rt_msghdr *rtm)); 8631145Sjulianvoid print_entry(struct sockaddr_dl *sdl, 8731145Sjulian struct sockaddr_inarp *sin, struct rt_msghdr *rtm); 8831145Sjulianvoid nuke_entry(struct sockaddr_dl *sdl, 8931145Sjulian struct sockaddr_inarp *sin, struct rt_msghdr *rtm); 9013977Sphkint delete(char *host, char *info); 9113977Sphkvoid ether_print(u_char *cp); 9213977Sphkvoid usage(void); 9313977Sphkint set(int argc, char **argv); 9431145Sjulianint get(char *host); 9513977Sphkint file(char *name); 9613977Sphkvoid getsocket(void); 9720690Snateint my_ether_aton(char *a, u_char *n); 9813977Sphkint rtmsg(int cmd); 9957727Sshinint get_ether_addr(u_int32_t ipaddr, u_char *hwaddr); 10013977Sphk 1011553Srgrimesstatic int pid; 10231145Sjulianstatic int nflag; /* no reverse dns lookups */ 10331145Sjulianstatic int aflag; /* do it for all entries */ 1041553Srgrimesstatic int s = -1; 1051553Srgrimes 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 11351250Sru#define ROUNDUP(a) \ 11451250Sru ((a) > 0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long)) 11531145Sjulian#define SETFUNC(f) { if (func) usage(); func = (f); } 11631145Sjulian 11713977Sphkint 11877870Srumain(int argc, char *argv[]) 1191553Srgrimes{ 12031145Sjulian int ch, func = 0; 12131145Sjulian int rtn = 0; 1221553Srgrimes 1231553Srgrimes pid = getpid(); 12424428Simp while ((ch = getopt(argc, argv, "andfsS")) != -1) 1251553Srgrimes switch((char)ch) { 1261553Srgrimes case 'a': 12731145Sjulian aflag = 1; 12831145Sjulian break; 1291553Srgrimes case 'd': 13031145Sjulian SETFUNC(F_DELETE); 13131145Sjulian break; 1321553Srgrimes case 'n': 1331553Srgrimes nflag = 1; 13431145Sjulian break; 13513977Sphk case 'S': 13631145Sjulian SETFUNC(F_REPLACE); 13731145Sjulian break; 1381553Srgrimes case 's': 13931145Sjulian SETFUNC(F_SET); 14031145Sjulian break; 1419874Sjkh case 'f' : 14231145Sjulian SETFUNC(F_FILESET); 14331145Sjulian break; 1441553Srgrimes case '?': 1451553Srgrimes default: 1461553Srgrimes usage(); 1471553Srgrimes } 14831145Sjulian argc -= optind; 14931145Sjulian argv += optind; 15031145Sjulian 15131145Sjulian if (!func) 15231145Sjulian func = F_GET; 15331145Sjulian switch (func) { 15431145Sjulian case F_GET: 15531145Sjulian if (aflag) { 15631145Sjulian if (argc != 0) 15731145Sjulian usage(); 15831145Sjulian search(0, print_entry); 15931145Sjulian } else { 16031145Sjulian if (argc != 1) 16131145Sjulian usage(); 16231145Sjulian get(argv[0]); 16331145Sjulian } 16431145Sjulian break; 16531145Sjulian case F_SET: 16631145Sjulian case F_REPLACE: 16777870Sru if (argc < 2 || argc > 6) 16831145Sjulian usage(); 16931145Sjulian if (func == F_REPLACE) 17031145Sjulian (void) delete(argv[0], NULL); 17131145Sjulian rtn = set(argc, argv) ? 1 : 0; 17231145Sjulian break; 17331145Sjulian case F_DELETE: 17431145Sjulian if (aflag) { 17531145Sjulian if (argc != 0) 17631145Sjulian usage(); 17731145Sjulian search(0, nuke_entry); 17831145Sjulian } else { 17931145Sjulian if (argc < 1 || argc > 2) 18031145Sjulian usage(); 18131145Sjulian rtn = delete(argv[0], argv[1]); 18231145Sjulian } 18331145Sjulian break; 18431145Sjulian case F_FILESET: 18531145Sjulian if (argc != 1) 18631145Sjulian usage(); 18731145Sjulian rtn = file(argv[0]); 18831145Sjulian break; 18931145Sjulian } 19031145Sjulian 19131145Sjulian return(rtn); 1921553Srgrimes} 1931553Srgrimes 1941553Srgrimes/* 1951553Srgrimes * Process a file to set standard arp entries 1961553Srgrimes */ 19713977Sphkint 19813977Sphkfile(char *name) 1991553Srgrimes{ 2001553Srgrimes FILE *fp; 2011553Srgrimes int i, retval; 2021553Srgrimes char line[100], arg[5][50], *args[5]; 2031553Srgrimes 20429060Scharnier if ((fp = fopen(name, "r")) == NULL) 20529060Scharnier errx(1, "cannot open %s", name); 2061553Srgrimes args[0] = &arg[0][0]; 2071553Srgrimes args[1] = &arg[1][0]; 2081553Srgrimes args[2] = &arg[2][0]; 2091553Srgrimes args[3] = &arg[3][0]; 2101553Srgrimes args[4] = &arg[4][0]; 2111553Srgrimes retval = 0; 2121553Srgrimes while(fgets(line, 100, fp) != NULL) { 21356127Skris i = sscanf(line, "%49s %49s %49s %49s %49s", arg[0], arg[1], 21456134Sjkh arg[2], arg[3], arg[4]); 2151553Srgrimes if (i < 2) { 21629060Scharnier warnx("bad line: %s", line); 2171553Srgrimes retval = 1; 2181553Srgrimes continue; 2191553Srgrimes } 2201553Srgrimes if (set(i, args)) 2211553Srgrimes retval = 1; 2221553Srgrimes } 2231553Srgrimes fclose(fp); 2241553Srgrimes return (retval); 2251553Srgrimes} 2261553Srgrimes 22713977Sphkvoid 22813977Sphkgetsocket(void) 22913977Sphk{ 2301553Srgrimes if (s < 0) { 2311553Srgrimes s = socket(PF_ROUTE, SOCK_RAW, 0); 23229060Scharnier if (s < 0) 23329060Scharnier err(1, "socket"); 2341553Srgrimes } 2351553Srgrimes} 2361553Srgrimes 2371553Srgrimesstruct sockaddr_in so_mask = {8, 0, 0, { 0xffffffff}}; 2381553Srgrimesstruct sockaddr_inarp blank_sin = {sizeof(blank_sin), AF_INET }, sin_m; 2391553Srgrimesstruct sockaddr_dl blank_sdl = {sizeof(blank_sdl), AF_LINK }, sdl_m; 24077870Sruint expire_time, flags, doing_proxy, proxy_only, found_entry; 2411553Srgrimesstruct { 2421553Srgrimes struct rt_msghdr m_rtm; 2431553Srgrimes char m_space[512]; 2441553Srgrimes} m_rtmsg; 2451553Srgrimes 2461553Srgrimes/* 2478857Srgrimes * Set an individual arp entry 2481553Srgrimes */ 24913977Sphkint 25013977Sphkset(int argc, char **argv) 2511553Srgrimes{ 2521553Srgrimes struct hostent *hp; 2531553Srgrimes register struct sockaddr_inarp *sin = &sin_m; 2541553Srgrimes register struct sockaddr_dl *sdl; 2551553Srgrimes register struct rt_msghdr *rtm = &(m_rtmsg.m_rtm); 2561553Srgrimes u_char *ea; 2571553Srgrimes char *host = argv[0], *eaddr = argv[1]; 2581553Srgrimes 2591553Srgrimes getsocket(); 2601553Srgrimes argc -= 2; 2611553Srgrimes argv += 2; 2621553Srgrimes sdl_m = blank_sdl; 2631553Srgrimes sin_m = blank_sin; 2641553Srgrimes sin->sin_addr.s_addr = inet_addr(host); 26577870Sru if (sin->sin_addr.s_addr == INADDR_NONE) { 2661553Srgrimes if (!(hp = gethostbyname(host))) { 26729060Scharnier warnx("%s: %s", host, hstrerror(h_errno)); 2681553Srgrimes return (1); 2691553Srgrimes } 2701553Srgrimes bcopy((char *)hp->h_addr, (char *)&sin->sin_addr, 2711553Srgrimes sizeof sin->sin_addr); 2721553Srgrimes } 27377870Sru doing_proxy = flags = proxy_only = expire_time = 0; 2741553Srgrimes while (argc-- > 0) { 2751553Srgrimes if (strncmp(argv[0], "temp", 4) == 0) { 27677870Sru struct timeval tv; 27777870Sru gettimeofday(&tv, 0); 27877870Sru expire_time = tv.tv_sec + 20 * 60; 2791553Srgrimes } 2801553Srgrimes else if (strncmp(argv[0], "pub", 3) == 0) { 2811553Srgrimes flags |= RTF_ANNOUNCE; 28277870Sru doing_proxy = 1; 28377870Sru if (argc && strncmp(argv[1], "only", 3) == 0) { 28477870Sru proxy_only = 1; 28577870Sru sin_m.sin_other = SIN_PROXY; 28677870Sru argc--; argv++; 28777870Sru } 2881553Srgrimes } else if (strncmp(argv[0], "trail", 5) == 0) { 2891553Srgrimes printf("%s: Sending trailers is no longer supported\n", 2901553Srgrimes host); 2911553Srgrimes } 2921553Srgrimes argv++; 2931553Srgrimes } 29413977Sphk ea = (u_char *)LLADDR(&sdl_m); 29513977Sphk if (doing_proxy && !strcmp(eaddr, "auto")) { 29613977Sphk if (!get_ether_addr(sin->sin_addr.s_addr, ea)) { 29773135Sru printf("no interface found for %s\n", 29873135Sru inet_ntoa(sin->sin_addr)); 29913977Sphk return (1); 30013977Sphk } 30113977Sphk sdl_m.sdl_alen = 6; 30213977Sphk } else { 30320690Snate if (my_ether_aton(eaddr, ea) == 0) 30413977Sphk sdl_m.sdl_alen = 6; 30513977Sphk } 3061553Srgrimestryagain: 3071553Srgrimes if (rtmsg(RTM_GET) < 0) { 30829060Scharnier warn("%s", host); 3091553Srgrimes return (1); 3101553Srgrimes } 3111553Srgrimes sin = (struct sockaddr_inarp *)(rtm + 1); 31251250Sru sdl = (struct sockaddr_dl *)(ROUNDUP(sin->sin_len) + (char *)sin); 3131553Srgrimes if (sin->sin_addr.s_addr == sin_m.sin_addr.s_addr) { 3141553Srgrimes if (sdl->sdl_family == AF_LINK && 3151553Srgrimes (rtm->rtm_flags & RTF_LLINFO) && 3161553Srgrimes !(rtm->rtm_flags & RTF_GATEWAY)) switch (sdl->sdl_type) { 3171553Srgrimes case IFT_ETHER: case IFT_FDDI: case IFT_ISO88023: 31875180Syar case IFT_ISO88024: case IFT_ISO88025: case IFT_L2VLAN: 3191553Srgrimes goto overwrite; 3201553Srgrimes } 3211553Srgrimes if (doing_proxy == 0) { 3221553Srgrimes printf("set: can only proxy for %s\n", host); 3231553Srgrimes return (1); 3241553Srgrimes } 3251553Srgrimes if (sin_m.sin_other & SIN_PROXY) { 3261553Srgrimes printf("set: proxy entry exists for non 802 device\n"); 3271553Srgrimes return(1); 3281553Srgrimes } 3291553Srgrimes sin_m.sin_other = SIN_PROXY; 33077870Sru proxy_only = 1; 3311553Srgrimes goto tryagain; 3321553Srgrimes } 3331553Srgrimesoverwrite: 3341553Srgrimes if (sdl->sdl_family != AF_LINK) { 3351553Srgrimes printf("cannot intuit interface index and type for %s\n", host); 3361553Srgrimes return (1); 3371553Srgrimes } 3381553Srgrimes sdl_m.sdl_type = sdl->sdl_type; 3391553Srgrimes sdl_m.sdl_index = sdl->sdl_index; 3401553Srgrimes return (rtmsg(RTM_ADD)); 3411553Srgrimes} 3421553Srgrimes 3431553Srgrimes/* 3441553Srgrimes * Display an individual arp entry 3451553Srgrimes */ 34631145Sjulianint 34713977Sphkget(char *host) 3481553Srgrimes{ 3491553Srgrimes struct hostent *hp; 3501553Srgrimes struct sockaddr_inarp *sin = &sin_m; 3511553Srgrimes 3521553Srgrimes sin_m = blank_sin; 3531553Srgrimes sin->sin_addr.s_addr = inet_addr(host); 35477870Sru if (sin->sin_addr.s_addr == INADDR_NONE) { 35529060Scharnier if (!(hp = gethostbyname(host))) 35629060Scharnier errx(1, "%s: %s", host, hstrerror(h_errno)); 3571553Srgrimes bcopy((char *)hp->h_addr, (char *)&sin->sin_addr, 3581553Srgrimes sizeof sin->sin_addr); 3591553Srgrimes } 36031145Sjulian search(sin->sin_addr.s_addr, print_entry); 3611553Srgrimes if (found_entry == 0) { 3621553Srgrimes printf("%s (%s) -- no entry\n", 3631553Srgrimes host, inet_ntoa(sin->sin_addr)); 36431145Sjulian return(1); 3651553Srgrimes } 36631145Sjulian return(0); 3671553Srgrimes} 3681553Srgrimes 3691553Srgrimes/* 3708857Srgrimes * Delete an arp entry 3711553Srgrimes */ 37213977Sphkint 37313977Sphkdelete(char *host, char *info) 3741553Srgrimes{ 3751553Srgrimes struct hostent *hp; 3761553Srgrimes register struct sockaddr_inarp *sin = &sin_m; 3771553Srgrimes register struct rt_msghdr *rtm = &m_rtmsg.m_rtm; 3781553Srgrimes struct sockaddr_dl *sdl; 3791553Srgrimes 3801553Srgrimes getsocket(); 3811553Srgrimes sin_m = blank_sin; 38277870Sru if (info) { 38377870Sru if (strncmp(info, "pub", 3) == 0) 38477870Sru sin_m.sin_other = SIN_PROXY; 38577870Sru else 38677870Sru usage(); 38777870Sru } 3881553Srgrimes sin->sin_addr.s_addr = inet_addr(host); 38977870Sru if (sin->sin_addr.s_addr == INADDR_NONE) { 3901553Srgrimes if (!(hp = gethostbyname(host))) { 39129060Scharnier warnx("%s: %s", host, hstrerror(h_errno)); 3921553Srgrimes return (1); 3931553Srgrimes } 3941553Srgrimes bcopy((char *)hp->h_addr, (char *)&sin->sin_addr, 3951553Srgrimes sizeof sin->sin_addr); 3961553Srgrimes } 3971553Srgrimestryagain: 3981553Srgrimes if (rtmsg(RTM_GET) < 0) { 39929060Scharnier warn("%s", host); 4001553Srgrimes return (1); 4011553Srgrimes } 4021553Srgrimes sin = (struct sockaddr_inarp *)(rtm + 1); 40351250Sru sdl = (struct sockaddr_dl *)(ROUNDUP(sin->sin_len) + (char *)sin); 4041553Srgrimes if (sin->sin_addr.s_addr == sin_m.sin_addr.s_addr) { 4051553Srgrimes if (sdl->sdl_family == AF_LINK && 4061553Srgrimes (rtm->rtm_flags & RTF_LLINFO) && 4071553Srgrimes !(rtm->rtm_flags & RTF_GATEWAY)) switch (sdl->sdl_type) { 4081553Srgrimes case IFT_ETHER: case IFT_FDDI: case IFT_ISO88023: 40975180Syar case IFT_ISO88024: case IFT_ISO88025: case IFT_L2VLAN: 4101553Srgrimes goto delete; 4111553Srgrimes } 4121553Srgrimes } 4131553Srgrimes if (sin_m.sin_other & SIN_PROXY) { 4141553Srgrimes fprintf(stderr, "delete: can't locate %s\n",host); 4151553Srgrimes return (1); 4161553Srgrimes } else { 4171553Srgrimes sin_m.sin_other = SIN_PROXY; 4181553Srgrimes goto tryagain; 4191553Srgrimes } 4201553Srgrimesdelete: 4211553Srgrimes if (sdl->sdl_family != AF_LINK) { 4221553Srgrimes printf("cannot locate %s\n", host); 4231553Srgrimes return (1); 4241553Srgrimes } 42513977Sphk if (rtmsg(RTM_DELETE) == 0) { 4261553Srgrimes printf("%s (%s) deleted\n", host, inet_ntoa(sin->sin_addr)); 42713977Sphk return (0); 42813977Sphk } 42913977Sphk return (1); 4301553Srgrimes} 4311553Srgrimes 4321553Srgrimes/* 43331145Sjulian * Search the arp table and do some action on matching entries 4341553Srgrimes */ 43513977Sphkvoid 43631145Sjuliansearch(u_long addr, void (*action)(struct sockaddr_dl *sdl, 43731145Sjulian struct sockaddr_inarp *sin, struct rt_msghdr *rtm)) 4381553Srgrimes{ 4391553Srgrimes int mib[6]; 4401553Srgrimes size_t needed; 44131145Sjulian char *lim, *buf, *next; 4421553Srgrimes struct rt_msghdr *rtm; 4431553Srgrimes struct sockaddr_inarp *sin; 4441553Srgrimes struct sockaddr_dl *sdl; 4451553Srgrimes 4461553Srgrimes mib[0] = CTL_NET; 4471553Srgrimes mib[1] = PF_ROUTE; 4481553Srgrimes mib[2] = 0; 4491553Srgrimes mib[3] = AF_INET; 4501553Srgrimes mib[4] = NET_RT_FLAGS; 4511553Srgrimes mib[5] = RTF_LLINFO; 4521553Srgrimes if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0) 45329060Scharnier errx(1, "route-sysctl-estimate"); 4541553Srgrimes if ((buf = malloc(needed)) == NULL) 45529060Scharnier errx(1, "malloc"); 4561553Srgrimes if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0) 45729060Scharnier errx(1, "actual retrieval of routing table"); 4581553Srgrimes lim = buf + needed; 4591553Srgrimes for (next = buf; next < lim; next += rtm->rtm_msglen) { 4601553Srgrimes rtm = (struct rt_msghdr *)next; 4611553Srgrimes sin = (struct sockaddr_inarp *)(rtm + 1); 46251456Sru (char *)sdl = (char *)sin + ROUNDUP(sin->sin_len); 4631553Srgrimes if (addr) { 4641553Srgrimes if (addr != sin->sin_addr.s_addr) 4651553Srgrimes continue; 4661553Srgrimes found_entry = 1; 4671553Srgrimes } 46831145Sjulian (*action)(sdl, sin, rtm); 4691553Srgrimes } 47076216Syar free(buf); 4711553Srgrimes} 4721553Srgrimes 47331145Sjulian/* 47431145Sjulian * Display an arp entry 47531145Sjulian */ 47613977Sphkvoid 47731145Sjulianprint_entry(struct sockaddr_dl *sdl, 47831145Sjulian struct sockaddr_inarp *sin, struct rt_msghdr *rtm) 47931145Sjulian{ 48077870Sru const char *host; 48131145Sjulian struct hostent *hp; 48284666Sru char ifname[IF_NAMESIZE]; 48344627Sjulian int seg; 48431145Sjulian 48531145Sjulian if (nflag == 0) 48631145Sjulian hp = gethostbyaddr((caddr_t)&(sin->sin_addr), 48731145Sjulian sizeof sin->sin_addr, AF_INET); 48831145Sjulian else 48931145Sjulian hp = 0; 49031145Sjulian if (hp) 49131145Sjulian host = hp->h_name; 49231145Sjulian else { 49331145Sjulian host = "?"; 49431145Sjulian if (h_errno == TRY_AGAIN) 49531145Sjulian nflag = 1; 49631145Sjulian } 49731145Sjulian printf("%s (%s) at ", host, inet_ntoa(sin->sin_addr)); 49831145Sjulian if (sdl->sdl_alen) 49931145Sjulian ether_print(LLADDR(sdl)); 50031145Sjulian else 50131145Sjulian printf("(incomplete)"); 50284666Sru if (if_indextoname(sdl->sdl_index, ifname) != NULL) 50384666Sru printf(" on %s", ifname); 50431145Sjulian if (rtm->rtm_rmx.rmx_expire == 0) 50531145Sjulian printf(" permanent"); 50631145Sjulian if (sin->sin_other & SIN_PROXY) 50731145Sjulian printf(" published (proxy only)"); 50831145Sjulian if (rtm->rtm_addrs & RTA_NETMASK) { 50931145Sjulian sin = (struct sockaddr_inarp *) 51051250Sru (ROUNDUP(sdl->sdl_len) + (char *)sdl); 51131145Sjulian if (sin->sin_addr.s_addr == 0xffffffff) 51231145Sjulian printf(" published"); 51331145Sjulian if (sin->sin_len != 8) 51451250Sru printf("(weird)"); 51531145Sjulian } 51644627Sjulian switch(sdl->sdl_type) { 51744627Sjulian case IFT_ETHER: 51844627Sjulian printf(" [ethernet]"); 51944627Sjulian break; 52044627Sjulian case IFT_ISO88025: 52144627Sjulian printf(" [token-ring]"); 52244627Sjulian break; 52385123Smdodd case IFT_FDDI: 52485123Smdodd printf(" [fddi]"); 52585123Smdodd break; 52685123Smdodd case IFT_ATM: 52785123Smdodd printf(" [atm]"); 52885123Smdodd break; 52975180Syar case IFT_L2VLAN: 53075180Syar printf(" [vlan]"); 53175180Syar break; 53244627Sjulian default: 53344627Sjulian } 53444627Sjulian if (sdl->sdl_rcf != NULL) { 53544627Sjulian printf(" rt=%x", ntohs(sdl->sdl_rcf)); 53644627Sjulian for (seg = 0; seg < ((((ntohs(sdl->sdl_rcf) & 0x1f00) >> 8) - 2 ) / 2); seg++) 53744627Sjulian printf(":%x", ntohs(sdl->sdl_route[seg])); 53844627Sjulian } 53944627Sjulian 54031145Sjulian printf("\n"); 54144627Sjulian 54231145Sjulian} 54331145Sjulian 54431145Sjulian/* 54531145Sjulian * Nuke an arp entry 54631145Sjulian */ 54731145Sjulianvoid 54831145Sjuliannuke_entry(struct sockaddr_dl *sdl, 54931145Sjulian struct sockaddr_inarp *sin, struct rt_msghdr *rtm) 55031145Sjulian{ 55131145Sjulian char ip[20]; 55231145Sjulian 55331145Sjulian snprintf(ip, sizeof(ip), "%s", inet_ntoa(sin->sin_addr)); 55431145Sjulian delete(ip, NULL); 55531145Sjulian} 55631145Sjulian 55731145Sjulianvoid 55813977Sphkether_print(u_char *cp) 5591553Srgrimes{ 56073973Sbillf printf("%02x:%02x:%02x:%02x:%02x:%02x", cp[0], cp[1], cp[2], cp[3], 56173973Sbillf cp[4], cp[5]); 5621553Srgrimes} 5631553Srgrimes 56413977Sphkint 56520690Snatemy_ether_aton(char *a, u_char *n) 5661553Srgrimes{ 5671553Srgrimes int i, o[6]; 5681553Srgrimes 5691553Srgrimes i = sscanf(a, "%x:%x:%x:%x:%x:%x", &o[0], &o[1], &o[2], 5701553Srgrimes &o[3], &o[4], &o[5]); 5711553Srgrimes if (i != 6) { 57229060Scharnier warnx("invalid Ethernet address '%s'", a); 5731553Srgrimes return (1); 5741553Srgrimes } 5751553Srgrimes for (i=0; i<6; i++) 5761553Srgrimes n[i] = o[i]; 5771553Srgrimes return (0); 5781553Srgrimes} 5791553Srgrimes 58013977Sphkvoid 58113977Sphkusage(void) 5821553Srgrimes{ 58331145Sjulian fprintf(stderr, "%s\n%s\n%s\n%s\n%s\n%s\n%s\n", 58429060Scharnier "usage: arp [-n] hostname", 58531145Sjulian " arp [-n] -a", 58677870Sru " arp -d hostname [pub]", 58731145Sjulian " arp -d -a", 58829060Scharnier " arp -s hostname ether_addr [temp] [pub]", 58929060Scharnier " arp -S hostname ether_addr [temp] [pub]", 59029060Scharnier " arp -f filename"); 5911553Srgrimes exit(1); 5921553Srgrimes} 5931553Srgrimes 59413977Sphkint 59513977Sphkrtmsg(int cmd) 5961553Srgrimes{ 5971553Srgrimes static int seq; 5981553Srgrimes int rlen; 5991553Srgrimes register struct rt_msghdr *rtm = &m_rtmsg.m_rtm; 6001553Srgrimes register char *cp = m_rtmsg.m_space; 6011553Srgrimes register int l; 6021553Srgrimes 6031553Srgrimes errno = 0; 6041553Srgrimes if (cmd == RTM_DELETE) 6051553Srgrimes goto doit; 6061553Srgrimes bzero((char *)&m_rtmsg, sizeof(m_rtmsg)); 6071553Srgrimes rtm->rtm_flags = flags; 6081553Srgrimes rtm->rtm_version = RTM_VERSION; 6091553Srgrimes 6101553Srgrimes switch (cmd) { 6111553Srgrimes default: 61229060Scharnier errx(1, "internal wrong cmd"); 6131553Srgrimes case RTM_ADD: 6141553Srgrimes rtm->rtm_addrs |= RTA_GATEWAY; 6151553Srgrimes rtm->rtm_rmx.rmx_expire = expire_time; 6161553Srgrimes rtm->rtm_inits = RTV_EXPIRE; 6171553Srgrimes rtm->rtm_flags |= (RTF_HOST | RTF_STATIC); 6181553Srgrimes sin_m.sin_other = 0; 6191553Srgrimes if (doing_proxy) { 62077870Sru if (proxy_only) 6211553Srgrimes sin_m.sin_other = SIN_PROXY; 6221553Srgrimes else { 6231553Srgrimes rtm->rtm_addrs |= RTA_NETMASK; 6241553Srgrimes rtm->rtm_flags &= ~RTF_HOST; 6251553Srgrimes } 6261553Srgrimes } 6271553Srgrimes /* FALLTHROUGH */ 6281553Srgrimes case RTM_GET: 6291553Srgrimes rtm->rtm_addrs |= RTA_DST; 6301553Srgrimes } 6311553Srgrimes#define NEXTADDR(w, s) \ 6321553Srgrimes if (rtm->rtm_addrs & (w)) { \ 63351250Sru bcopy((char *)&s, cp, sizeof(s)); cp += ROUNDUP(sizeof(s));} 6341553Srgrimes 6351553Srgrimes NEXTADDR(RTA_DST, sin_m); 6361553Srgrimes NEXTADDR(RTA_GATEWAY, sdl_m); 6371553Srgrimes NEXTADDR(RTA_NETMASK, so_mask); 6381553Srgrimes 6391553Srgrimes rtm->rtm_msglen = cp - (char *)&m_rtmsg; 6401553Srgrimesdoit: 6411553Srgrimes l = rtm->rtm_msglen; 6421553Srgrimes rtm->rtm_seq = ++seq; 6431553Srgrimes rtm->rtm_type = cmd; 6441553Srgrimes if ((rlen = write(s, (char *)&m_rtmsg, l)) < 0) { 6451553Srgrimes if (errno != ESRCH || cmd != RTM_DELETE) { 64629060Scharnier warn("writing to routing socket"); 6471553Srgrimes return (-1); 6481553Srgrimes } 6491553Srgrimes } 6501553Srgrimes do { 6511553Srgrimes l = read(s, (char *)&m_rtmsg, sizeof(m_rtmsg)); 6521553Srgrimes } while (l > 0 && (rtm->rtm_seq != seq || rtm->rtm_pid != pid)); 6531553Srgrimes if (l < 0) 65429060Scharnier warn("read from routing socket"); 6551553Srgrimes return (0); 6561553Srgrimes} 6571553Srgrimes 65813977Sphk/* 65913977Sphk * get_ether_addr - get the hardware address of an interface on the 66013977Sphk * the same subnet as ipaddr. 66113977Sphk */ 66213977Sphk#define MAX_IFS 32 66313977Sphk 66413977Sphkint 66557727Sshinget_ether_addr(u_int32_t ipaddr, u_char *hwaddr) 66613977Sphk{ 66713977Sphk struct ifreq *ifr, *ifend, *ifp; 66857727Sshin u_int32_t ina, mask; 66913977Sphk struct sockaddr_dl *dla; 67013977Sphk struct ifreq ifreq; 67113977Sphk struct ifconf ifc; 67213977Sphk struct ifreq ifs[MAX_IFS]; 67313977Sphk int s; 67413977Sphk 67513977Sphk s = socket(AF_INET, SOCK_DGRAM, 0); 67629060Scharnier if (s < 0) 67729060Scharnier err(1, "socket"); 67813977Sphk 67913977Sphk ifc.ifc_len = sizeof(ifs); 68013977Sphk ifc.ifc_req = ifs; 68113977Sphk if (ioctl(s, SIOCGIFCONF, &ifc) < 0) { 68229060Scharnier warnx("ioctl(SIOCGIFCONF)"); 68313977Sphk close(s); 68413977Sphk return 0; 68513977Sphk } 68613977Sphk 68713977Sphk /* 68813977Sphk * Scan through looking for an interface with an Internet 68913977Sphk * address on the same subnet as `ipaddr'. 69013977Sphk */ 69113977Sphk ifend = (struct ifreq *) (ifc.ifc_buf + ifc.ifc_len); 69213977Sphk for (ifr = ifc.ifc_req; ifr < ifend; ) { 69313977Sphk if (ifr->ifr_addr.sa_family == AF_INET) { 69413977Sphk ina = ((struct sockaddr_in *) 69513977Sphk &ifr->ifr_addr)->sin_addr.s_addr; 69613977Sphk strncpy(ifreq.ifr_name, ifr->ifr_name, 69713977Sphk sizeof(ifreq.ifr_name)); 69813977Sphk /* 69913977Sphk * Check that the interface is up, 70013977Sphk * and not point-to-point or loopback. 70113977Sphk */ 70213977Sphk if (ioctl(s, SIOCGIFFLAGS, &ifreq) < 0) 70313977Sphk continue; 70413977Sphk if ((ifreq.ifr_flags & 70513977Sphk (IFF_UP|IFF_BROADCAST|IFF_POINTOPOINT| 70613977Sphk IFF_LOOPBACK|IFF_NOARP)) 70713977Sphk != (IFF_UP|IFF_BROADCAST)) 70813977Sphk goto nextif; 70913977Sphk /* 71013977Sphk * Get its netmask and check that it's on 71113977Sphk * the right subnet. 71213977Sphk */ 71313977Sphk if (ioctl(s, SIOCGIFNETMASK, &ifreq) < 0) 71413977Sphk continue; 71513977Sphk mask = ((struct sockaddr_in *) 71613977Sphk &ifreq.ifr_addr)->sin_addr.s_addr; 71713977Sphk if ((ipaddr & mask) != (ina & mask)) 71813977Sphk goto nextif; 71913977Sphk break; 72013977Sphk } 72113977Sphknextif: 72247753Sarchie ifr = (struct ifreq *) ((char *)&ifr->ifr_addr 72347753Sarchie + MAX(ifr->ifr_addr.sa_len, sizeof(ifr->ifr_addr))); 72413977Sphk } 72513977Sphk 72613977Sphk if (ifr >= ifend) { 72713977Sphk close(s); 72813977Sphk return 0; 72913977Sphk } 73013977Sphk 73113977Sphk /* 73213977Sphk * Now scan through again looking for a link-level address 73313977Sphk * for this interface. 73413977Sphk */ 73513977Sphk ifp = ifr; 73613977Sphk for (ifr = ifc.ifc_req; ifr < ifend; ) { 73713977Sphk if (strcmp(ifp->ifr_name, ifr->ifr_name) == 0 73813977Sphk && ifr->ifr_addr.sa_family == AF_LINK) { 73913977Sphk /* 74013977Sphk * Found the link-level address - copy it out 74113977Sphk */ 74213977Sphk dla = (struct sockaddr_dl *) &ifr->ifr_addr; 74313977Sphk memcpy(hwaddr, LLADDR(dla), dla->sdl_alen); 74413977Sphk close (s); 74513977Sphk printf("using interface %s for proxy with address ", 74613977Sphk ifp->ifr_name); 74713977Sphk ether_print(hwaddr); 74813977Sphk printf("\n"); 74913977Sphk return dla->sdl_alen; 75013977Sphk } 75147753Sarchie ifr = (struct ifreq *) ((char *)&ifr->ifr_addr 75247753Sarchie + MAX(ifr->ifr_addr.sa_len, sizeof(ifr->ifr_addr))); 75313977Sphk } 75413977Sphk return 0; 75513977Sphk} 756