arp.c revision 93590
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 93590 2002-04-01 21:13:17Z mike $"; 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> 8193590Smike#include <string.h> 8229060Scharnier#include <strings.h> 8313977Sphk#include <unistd.h> 841553Srgrimes 8531145Sjulianvoid search(u_long addr, void (*action)(struct sockaddr_dl *sdl, 8631145Sjulian struct sockaddr_inarp *sin, struct rt_msghdr *rtm)); 8731145Sjulianvoid print_entry(struct sockaddr_dl *sdl, 8887598Smikeh struct sockaddr_inarp *addr, struct rt_msghdr *rtm); 8931145Sjulianvoid nuke_entry(struct sockaddr_dl *sdl, 9087598Smikeh struct sockaddr_inarp *addr, struct rt_msghdr *rtm); 9113977Sphkint delete(char *host, char *info); 9213977Sphkvoid ether_print(u_char *cp); 9313977Sphkvoid usage(void); 9413977Sphkint set(int argc, char **argv); 9531145Sjulianint get(char *host); 9613977Sphkint file(char *name); 9713977Sphkvoid getsocket(void); 9820690Snateint my_ether_aton(char *a, u_char *n); 9913977Sphkint rtmsg(int cmd); 10057727Sshinint get_ether_addr(u_int32_t ipaddr, u_char *hwaddr); 10113977Sphk 1021553Srgrimesstatic int pid; 10331145Sjulianstatic int nflag; /* no reverse dns lookups */ 10431145Sjulianstatic int aflag; /* do it for all entries */ 1051553Srgrimesstatic int s = -1; 1061553Srgrimes 10787598Smikehstruct sockaddr_in so_mask; 10887598Smikehstruct sockaddr_inarp blank_sin, sin_m; 10987598Smikehstruct sockaddr_dl blank_sdl, sdl_m; 11087598Smikehint expire_time, flags, doing_proxy, proxy_only, found_entry; 11187598Smikehstruct { 11287598Smikeh struct rt_msghdr m_rtm; 11387598Smikeh char m_space[512]; 11487598Smikeh} m_rtmsg; 11587598Smikeh 11631145Sjulian/* which function we're supposed to do */ 11731145Sjulian#define F_GET 1 11831145Sjulian#define F_SET 2 11931145Sjulian#define F_FILESET 3 12031145Sjulian#define F_REPLACE 4 12131145Sjulian#define F_DELETE 5 12231145Sjulian 12351250Sru#define ROUNDUP(a) \ 12451250Sru ((a) > 0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long)) 12531145Sjulian#define SETFUNC(f) { if (func) usage(); func = (f); } 12631145Sjulian 12713977Sphkint 12877870Srumain(int argc, char *argv[]) 1291553Srgrimes{ 13031145Sjulian int ch, func = 0; 13131145Sjulian int rtn = 0; 1321553Srgrimes 1331553Srgrimes pid = getpid(); 13424428Simp while ((ch = getopt(argc, argv, "andfsS")) != -1) 1351553Srgrimes switch((char)ch) { 1361553Srgrimes case 'a': 13731145Sjulian aflag = 1; 13831145Sjulian break; 1391553Srgrimes case 'd': 14031145Sjulian SETFUNC(F_DELETE); 14131145Sjulian break; 1421553Srgrimes case 'n': 1431553Srgrimes nflag = 1; 14431145Sjulian break; 14513977Sphk case 'S': 14631145Sjulian SETFUNC(F_REPLACE); 14731145Sjulian break; 1481553Srgrimes case 's': 14931145Sjulian SETFUNC(F_SET); 15031145Sjulian break; 1519874Sjkh case 'f' : 15231145Sjulian SETFUNC(F_FILESET); 15331145Sjulian break; 1541553Srgrimes case '?': 1551553Srgrimes default: 1561553Srgrimes usage(); 1571553Srgrimes } 15831145Sjulian argc -= optind; 15931145Sjulian argv += optind; 16031145Sjulian 16187598Smikeh bzero(&so_mask, sizeof(so_mask)); 16292735Smikeh so_mask.sin_len = 8; 16387598Smikeh so_mask.sin_addr.s_addr = 0xffffffff; 16487598Smikeh bzero(&blank_sin, sizeof(blank_sin)); 16587598Smikeh blank_sin.sin_len = sizeof(blank_sin); 16687598Smikeh blank_sin.sin_family = AF_INET; 16787598Smikeh bzero(&blank_sdl, sizeof(blank_sdl)); 16887598Smikeh blank_sdl.sdl_len = sizeof(blank_sdl); 16987598Smikeh blank_sdl.sdl_family = AF_LINK; 17087598Smikeh 17131145Sjulian if (!func) 17231145Sjulian func = F_GET; 17331145Sjulian switch (func) { 17431145Sjulian case F_GET: 17531145Sjulian if (aflag) { 17631145Sjulian if (argc != 0) 17731145Sjulian usage(); 17831145Sjulian search(0, print_entry); 17931145Sjulian } else { 18031145Sjulian if (argc != 1) 18131145Sjulian usage(); 18231145Sjulian get(argv[0]); 18331145Sjulian } 18431145Sjulian break; 18531145Sjulian case F_SET: 18631145Sjulian case F_REPLACE: 18777870Sru if (argc < 2 || argc > 6) 18831145Sjulian usage(); 18931145Sjulian if (func == F_REPLACE) 19031145Sjulian (void) delete(argv[0], NULL); 19131145Sjulian rtn = set(argc, argv) ? 1 : 0; 19231145Sjulian break; 19331145Sjulian case F_DELETE: 19431145Sjulian if (aflag) { 19531145Sjulian if (argc != 0) 19631145Sjulian usage(); 19731145Sjulian search(0, nuke_entry); 19831145Sjulian } else { 19931145Sjulian if (argc < 1 || argc > 2) 20031145Sjulian usage(); 20131145Sjulian rtn = delete(argv[0], argv[1]); 20231145Sjulian } 20331145Sjulian break; 20431145Sjulian case F_FILESET: 20531145Sjulian if (argc != 1) 20631145Sjulian usage(); 20731145Sjulian rtn = file(argv[0]); 20831145Sjulian break; 20931145Sjulian } 21031145Sjulian 21131145Sjulian return(rtn); 2121553Srgrimes} 2131553Srgrimes 2141553Srgrimes/* 2151553Srgrimes * Process a file to set standard arp entries 2161553Srgrimes */ 21713977Sphkint 21813977Sphkfile(char *name) 2191553Srgrimes{ 2201553Srgrimes FILE *fp; 2211553Srgrimes int i, retval; 2221553Srgrimes char line[100], arg[5][50], *args[5]; 2231553Srgrimes 22429060Scharnier if ((fp = fopen(name, "r")) == NULL) 22529060Scharnier errx(1, "cannot open %s", name); 2261553Srgrimes args[0] = &arg[0][0]; 2271553Srgrimes args[1] = &arg[1][0]; 2281553Srgrimes args[2] = &arg[2][0]; 2291553Srgrimes args[3] = &arg[3][0]; 2301553Srgrimes args[4] = &arg[4][0]; 2311553Srgrimes retval = 0; 2321553Srgrimes while(fgets(line, 100, fp) != NULL) { 23356127Skris i = sscanf(line, "%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 24713977Sphkvoid 24813977Sphkgetsocket(void) 24913977Sphk{ 2501553Srgrimes if (s < 0) { 2511553Srgrimes s = socket(PF_ROUTE, SOCK_RAW, 0); 25229060Scharnier if (s < 0) 25329060Scharnier err(1, "socket"); 2541553Srgrimes } 2551553Srgrimes} 2561553Srgrimes 2571553Srgrimes/* 2588857Srgrimes * Set an individual arp entry 2591553Srgrimes */ 26013977Sphkint 26113977Sphkset(int argc, char **argv) 2621553Srgrimes{ 2631553Srgrimes struct hostent *hp; 26487598Smikeh register struct sockaddr_inarp *addr = &sin_m; 2651553Srgrimes register struct sockaddr_dl *sdl; 2661553Srgrimes register struct rt_msghdr *rtm = &(m_rtmsg.m_rtm); 2671553Srgrimes u_char *ea; 2681553Srgrimes char *host = argv[0], *eaddr = argv[1]; 2691553Srgrimes 2701553Srgrimes getsocket(); 2711553Srgrimes argc -= 2; 2721553Srgrimes argv += 2; 2731553Srgrimes sdl_m = blank_sdl; 2741553Srgrimes sin_m = blank_sin; 27587598Smikeh addr->sin_addr.s_addr = inet_addr(host); 27687598Smikeh if (addr->sin_addr.s_addr == INADDR_NONE) { 2771553Srgrimes if (!(hp = gethostbyname(host))) { 27829060Scharnier warnx("%s: %s", host, hstrerror(h_errno)); 2791553Srgrimes return (1); 2801553Srgrimes } 28187598Smikeh bcopy((char *)hp->h_addr, (char *)&addr->sin_addr, 28287598Smikeh sizeof addr->sin_addr); 2831553Srgrimes } 28477870Sru doing_proxy = flags = proxy_only = expire_time = 0; 2851553Srgrimes while (argc-- > 0) { 2861553Srgrimes if (strncmp(argv[0], "temp", 4) == 0) { 28777870Sru struct timeval tv; 28877870Sru gettimeofday(&tv, 0); 28977870Sru expire_time = tv.tv_sec + 20 * 60; 2901553Srgrimes } 2911553Srgrimes else if (strncmp(argv[0], "pub", 3) == 0) { 2921553Srgrimes flags |= RTF_ANNOUNCE; 29377870Sru doing_proxy = 1; 29477870Sru if (argc && strncmp(argv[1], "only", 3) == 0) { 29577870Sru proxy_only = 1; 29677870Sru sin_m.sin_other = SIN_PROXY; 29777870Sru argc--; argv++; 29877870Sru } 2991553Srgrimes } else if (strncmp(argv[0], "trail", 5) == 0) { 3001553Srgrimes printf("%s: Sending trailers is no longer supported\n", 3011553Srgrimes host); 3021553Srgrimes } 3031553Srgrimes argv++; 3041553Srgrimes } 30513977Sphk ea = (u_char *)LLADDR(&sdl_m); 30613977Sphk if (doing_proxy && !strcmp(eaddr, "auto")) { 30787598Smikeh if (!get_ether_addr(addr->sin_addr.s_addr, ea)) { 30873135Sru printf("no interface found for %s\n", 30987598Smikeh inet_ntoa(addr->sin_addr)); 31013977Sphk return (1); 31113977Sphk } 31213977Sphk sdl_m.sdl_alen = 6; 31313977Sphk } else { 31420690Snate if (my_ether_aton(eaddr, ea) == 0) 31513977Sphk sdl_m.sdl_alen = 6; 31613977Sphk } 3171553Srgrimestryagain: 3181553Srgrimes if (rtmsg(RTM_GET) < 0) { 31929060Scharnier warn("%s", host); 3201553Srgrimes return (1); 3211553Srgrimes } 32287598Smikeh addr = (struct sockaddr_inarp *)(rtm + 1); 32387598Smikeh sdl = (struct sockaddr_dl *)(ROUNDUP(addr->sin_len) + (char *)addr); 32487598Smikeh if (addr->sin_addr.s_addr == sin_m.sin_addr.s_addr) { 3251553Srgrimes if (sdl->sdl_family == AF_LINK && 3261553Srgrimes (rtm->rtm_flags & RTF_LLINFO) && 3271553Srgrimes !(rtm->rtm_flags & RTF_GATEWAY)) switch (sdl->sdl_type) { 3281553Srgrimes case IFT_ETHER: case IFT_FDDI: case IFT_ISO88023: 32975180Syar case IFT_ISO88024: case IFT_ISO88025: case IFT_L2VLAN: 3301553Srgrimes goto overwrite; 3311553Srgrimes } 3321553Srgrimes if (doing_proxy == 0) { 3331553Srgrimes printf("set: can only proxy for %s\n", host); 3341553Srgrimes return (1); 3351553Srgrimes } 3361553Srgrimes if (sin_m.sin_other & SIN_PROXY) { 3371553Srgrimes printf("set: proxy entry exists for non 802 device\n"); 3381553Srgrimes return(1); 3391553Srgrimes } 3401553Srgrimes sin_m.sin_other = SIN_PROXY; 34177870Sru proxy_only = 1; 3421553Srgrimes goto tryagain; 3431553Srgrimes } 3441553Srgrimesoverwrite: 3451553Srgrimes if (sdl->sdl_family != AF_LINK) { 3461553Srgrimes printf("cannot intuit interface index and type for %s\n", host); 3471553Srgrimes return (1); 3481553Srgrimes } 3491553Srgrimes sdl_m.sdl_type = sdl->sdl_type; 3501553Srgrimes sdl_m.sdl_index = sdl->sdl_index; 3511553Srgrimes return (rtmsg(RTM_ADD)); 3521553Srgrimes} 3531553Srgrimes 3541553Srgrimes/* 3551553Srgrimes * Display an individual arp entry 3561553Srgrimes */ 35731145Sjulianint 35813977Sphkget(char *host) 3591553Srgrimes{ 3601553Srgrimes struct hostent *hp; 36187598Smikeh struct sockaddr_inarp *addr = &sin_m; 3621553Srgrimes 3631553Srgrimes sin_m = blank_sin; 36487598Smikeh addr->sin_addr.s_addr = inet_addr(host); 36587598Smikeh if (addr->sin_addr.s_addr == INADDR_NONE) { 36629060Scharnier if (!(hp = gethostbyname(host))) 36729060Scharnier errx(1, "%s: %s", host, hstrerror(h_errno)); 36887598Smikeh bcopy((char *)hp->h_addr, (char *)&addr->sin_addr, 36987598Smikeh sizeof addr->sin_addr); 3701553Srgrimes } 37187598Smikeh search(addr->sin_addr.s_addr, print_entry); 3721553Srgrimes if (found_entry == 0) { 3731553Srgrimes printf("%s (%s) -- no entry\n", 37487598Smikeh host, inet_ntoa(addr->sin_addr)); 37531145Sjulian return(1); 3761553Srgrimes } 37731145Sjulian return(0); 3781553Srgrimes} 3791553Srgrimes 3801553Srgrimes/* 3818857Srgrimes * Delete an arp entry 3821553Srgrimes */ 38313977Sphkint 38413977Sphkdelete(char *host, char *info) 3851553Srgrimes{ 3861553Srgrimes struct hostent *hp; 38787598Smikeh register struct sockaddr_inarp *addr = &sin_m; 3881553Srgrimes register struct rt_msghdr *rtm = &m_rtmsg.m_rtm; 3891553Srgrimes struct sockaddr_dl *sdl; 3901553Srgrimes 3911553Srgrimes getsocket(); 3921553Srgrimes sin_m = blank_sin; 39377870Sru if (info) { 39477870Sru if (strncmp(info, "pub", 3) == 0) 39577870Sru sin_m.sin_other = SIN_PROXY; 39677870Sru else 39777870Sru usage(); 39877870Sru } 39987598Smikeh addr->sin_addr.s_addr = inet_addr(host); 40087598Smikeh if (addr->sin_addr.s_addr == INADDR_NONE) { 4011553Srgrimes if (!(hp = gethostbyname(host))) { 40229060Scharnier warnx("%s: %s", host, hstrerror(h_errno)); 4031553Srgrimes return (1); 4041553Srgrimes } 40587598Smikeh bcopy((char *)hp->h_addr, (char *)&addr->sin_addr, 40687598Smikeh sizeof addr->sin_addr); 4071553Srgrimes } 4081553Srgrimestryagain: 4091553Srgrimes if (rtmsg(RTM_GET) < 0) { 41029060Scharnier warn("%s", host); 4111553Srgrimes return (1); 4121553Srgrimes } 41387598Smikeh addr = (struct sockaddr_inarp *)(rtm + 1); 41487598Smikeh sdl = (struct sockaddr_dl *)(ROUNDUP(addr->sin_len) + (char *)addr); 41587598Smikeh if (addr->sin_addr.s_addr == sin_m.sin_addr.s_addr) { 4161553Srgrimes if (sdl->sdl_family == AF_LINK && 4171553Srgrimes (rtm->rtm_flags & RTF_LLINFO) && 4181553Srgrimes !(rtm->rtm_flags & RTF_GATEWAY)) switch (sdl->sdl_type) { 4191553Srgrimes case IFT_ETHER: case IFT_FDDI: case IFT_ISO88023: 42075180Syar case IFT_ISO88024: case IFT_ISO88025: case IFT_L2VLAN: 4211553Srgrimes goto delete; 4221553Srgrimes } 4231553Srgrimes } 4241553Srgrimes if (sin_m.sin_other & SIN_PROXY) { 4251553Srgrimes fprintf(stderr, "delete: can't locate %s\n",host); 4261553Srgrimes return (1); 4271553Srgrimes } else { 4281553Srgrimes sin_m.sin_other = SIN_PROXY; 4291553Srgrimes goto tryagain; 4301553Srgrimes } 4311553Srgrimesdelete: 4321553Srgrimes if (sdl->sdl_family != AF_LINK) { 4331553Srgrimes printf("cannot locate %s\n", host); 4341553Srgrimes return (1); 4351553Srgrimes } 43613977Sphk if (rtmsg(RTM_DELETE) == 0) { 43787598Smikeh printf("%s (%s) deleted\n", host, inet_ntoa(addr->sin_addr)); 43813977Sphk return (0); 43913977Sphk } 44013977Sphk return (1); 4411553Srgrimes} 4421553Srgrimes 4431553Srgrimes/* 44431145Sjulian * Search the arp table and do some action on matching entries 4451553Srgrimes */ 44613977Sphkvoid 44731145Sjuliansearch(u_long addr, void (*action)(struct sockaddr_dl *sdl, 44831145Sjulian struct sockaddr_inarp *sin, struct rt_msghdr *rtm)) 4491553Srgrimes{ 4501553Srgrimes int mib[6]; 4511553Srgrimes size_t needed; 45231145Sjulian char *lim, *buf, *next; 4531553Srgrimes struct rt_msghdr *rtm; 45487598Smikeh struct sockaddr_inarp *sin2; 4551553Srgrimes struct sockaddr_dl *sdl; 4561553Srgrimes 4571553Srgrimes mib[0] = CTL_NET; 4581553Srgrimes mib[1] = PF_ROUTE; 4591553Srgrimes mib[2] = 0; 4601553Srgrimes mib[3] = AF_INET; 4611553Srgrimes mib[4] = NET_RT_FLAGS; 4621553Srgrimes mib[5] = RTF_LLINFO; 4631553Srgrimes if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0) 46429060Scharnier errx(1, "route-sysctl-estimate"); 4651553Srgrimes if ((buf = malloc(needed)) == NULL) 46629060Scharnier errx(1, "malloc"); 4671553Srgrimes if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0) 46829060Scharnier errx(1, "actual retrieval of routing table"); 4691553Srgrimes lim = buf + needed; 4701553Srgrimes for (next = buf; next < lim; next += rtm->rtm_msglen) { 4711553Srgrimes rtm = (struct rt_msghdr *)next; 47287598Smikeh sin2 = (struct sockaddr_inarp *)(rtm + 1); 47387598Smikeh (char *)sdl = (char *)sin2 + ROUNDUP(sin2->sin_len); 4741553Srgrimes if (addr) { 47587598Smikeh if (addr != sin2->sin_addr.s_addr) 4761553Srgrimes continue; 4771553Srgrimes found_entry = 1; 4781553Srgrimes } 47987598Smikeh (*action)(sdl, sin2, rtm); 4801553Srgrimes } 48176216Syar free(buf); 4821553Srgrimes} 4831553Srgrimes 48431145Sjulian/* 48531145Sjulian * Display an arp entry 48631145Sjulian */ 48713977Sphkvoid 48831145Sjulianprint_entry(struct sockaddr_dl *sdl, 48987598Smikeh struct sockaddr_inarp *addr, struct rt_msghdr *rtm) 49031145Sjulian{ 49177870Sru const char *host; 49231145Sjulian struct hostent *hp; 49384666Sru char ifname[IF_NAMESIZE]; 49444627Sjulian int seg; 49531145Sjulian 49631145Sjulian if (nflag == 0) 49787598Smikeh hp = gethostbyaddr((caddr_t)&(addr->sin_addr), 49887598Smikeh sizeof addr->sin_addr, AF_INET); 49931145Sjulian else 50031145Sjulian hp = 0; 50131145Sjulian if (hp) 50231145Sjulian host = hp->h_name; 50331145Sjulian else { 50431145Sjulian host = "?"; 50531145Sjulian if (h_errno == TRY_AGAIN) 50631145Sjulian nflag = 1; 50731145Sjulian } 50887598Smikeh printf("%s (%s) at ", host, inet_ntoa(addr->sin_addr)); 50931145Sjulian if (sdl->sdl_alen) 51031145Sjulian ether_print(LLADDR(sdl)); 51131145Sjulian else 51231145Sjulian printf("(incomplete)"); 51384666Sru if (if_indextoname(sdl->sdl_index, ifname) != NULL) 51484666Sru printf(" on %s", ifname); 51531145Sjulian if (rtm->rtm_rmx.rmx_expire == 0) 51631145Sjulian printf(" permanent"); 51787598Smikeh if (addr->sin_other & SIN_PROXY) 51831145Sjulian printf(" published (proxy only)"); 51931145Sjulian if (rtm->rtm_addrs & RTA_NETMASK) { 52087598Smikeh addr = (struct sockaddr_inarp *) 52151250Sru (ROUNDUP(sdl->sdl_len) + (char *)sdl); 52287598Smikeh if (addr->sin_addr.s_addr == 0xffffffff) 52331145Sjulian printf(" published"); 52487598Smikeh if (addr->sin_len != 8) 52551250Sru printf("(weird)"); 52631145Sjulian } 52744627Sjulian switch(sdl->sdl_type) { 52844627Sjulian case IFT_ETHER: 52944627Sjulian printf(" [ethernet]"); 53044627Sjulian break; 53144627Sjulian case IFT_ISO88025: 53244627Sjulian printf(" [token-ring]"); 53344627Sjulian break; 53485123Smdodd case IFT_FDDI: 53585123Smdodd printf(" [fddi]"); 53685123Smdodd break; 53785123Smdodd case IFT_ATM: 53885123Smdodd printf(" [atm]"); 53985123Smdodd break; 54075180Syar case IFT_L2VLAN: 54175180Syar printf(" [vlan]"); 54275180Syar break; 54344627Sjulian default: 54444627Sjulian } 54544627Sjulian if (sdl->sdl_rcf != NULL) { 54644627Sjulian printf(" rt=%x", ntohs(sdl->sdl_rcf)); 54744627Sjulian for (seg = 0; seg < ((((ntohs(sdl->sdl_rcf) & 0x1f00) >> 8) - 2 ) / 2); seg++) 54844627Sjulian printf(":%x", ntohs(sdl->sdl_route[seg])); 54944627Sjulian } 55044627Sjulian 55131145Sjulian printf("\n"); 55244627Sjulian 55331145Sjulian} 55431145Sjulian 55531145Sjulian/* 55631145Sjulian * Nuke an arp entry 55731145Sjulian */ 55831145Sjulianvoid 55987598Smikehnuke_entry(struct sockaddr_dl *sdl __unused, 56087598Smikeh struct sockaddr_inarp *addr, struct rt_msghdr *rtm __unused) 56131145Sjulian{ 56231145Sjulian char ip[20]; 56331145Sjulian 56487598Smikeh snprintf(ip, sizeof(ip), "%s", inet_ntoa(addr->sin_addr)); 56531145Sjulian delete(ip, NULL); 56631145Sjulian} 56731145Sjulian 56831145Sjulianvoid 56913977Sphkether_print(u_char *cp) 5701553Srgrimes{ 57173973Sbillf printf("%02x:%02x:%02x:%02x:%02x:%02x", cp[0], cp[1], cp[2], cp[3], 57273973Sbillf cp[4], cp[5]); 5731553Srgrimes} 5741553Srgrimes 57513977Sphkint 57620690Snatemy_ether_aton(char *a, u_char *n) 5771553Srgrimes{ 5781553Srgrimes int i, o[6]; 5791553Srgrimes 5801553Srgrimes i = sscanf(a, "%x:%x:%x:%x:%x:%x", &o[0], &o[1], &o[2], 5811553Srgrimes &o[3], &o[4], &o[5]); 5821553Srgrimes if (i != 6) { 58329060Scharnier warnx("invalid Ethernet address '%s'", a); 5841553Srgrimes return (1); 5851553Srgrimes } 5861553Srgrimes for (i=0; i<6; i++) 5871553Srgrimes n[i] = o[i]; 5881553Srgrimes return (0); 5891553Srgrimes} 5901553Srgrimes 59113977Sphkvoid 59213977Sphkusage(void) 5931553Srgrimes{ 59431145Sjulian fprintf(stderr, "%s\n%s\n%s\n%s\n%s\n%s\n%s\n", 59529060Scharnier "usage: arp [-n] hostname", 59631145Sjulian " arp [-n] -a", 59777870Sru " arp -d hostname [pub]", 59831145Sjulian " arp -d -a", 59929060Scharnier " arp -s hostname ether_addr [temp] [pub]", 60029060Scharnier " arp -S hostname ether_addr [temp] [pub]", 60129060Scharnier " arp -f filename"); 6021553Srgrimes exit(1); 6031553Srgrimes} 6041553Srgrimes 60513977Sphkint 60613977Sphkrtmsg(int cmd) 6071553Srgrimes{ 6081553Srgrimes static int seq; 6091553Srgrimes int rlen; 6101553Srgrimes register struct rt_msghdr *rtm = &m_rtmsg.m_rtm; 6111553Srgrimes register char *cp = m_rtmsg.m_space; 6121553Srgrimes register int l; 6131553Srgrimes 6141553Srgrimes errno = 0; 6151553Srgrimes if (cmd == RTM_DELETE) 6161553Srgrimes goto doit; 6171553Srgrimes bzero((char *)&m_rtmsg, sizeof(m_rtmsg)); 6181553Srgrimes rtm->rtm_flags = flags; 6191553Srgrimes rtm->rtm_version = RTM_VERSION; 6201553Srgrimes 6211553Srgrimes switch (cmd) { 6221553Srgrimes default: 62329060Scharnier errx(1, "internal wrong cmd"); 6241553Srgrimes case RTM_ADD: 6251553Srgrimes rtm->rtm_addrs |= RTA_GATEWAY; 6261553Srgrimes rtm->rtm_rmx.rmx_expire = expire_time; 6271553Srgrimes rtm->rtm_inits = RTV_EXPIRE; 6281553Srgrimes rtm->rtm_flags |= (RTF_HOST | RTF_STATIC); 6291553Srgrimes sin_m.sin_other = 0; 6301553Srgrimes if (doing_proxy) { 63177870Sru if (proxy_only) 6321553Srgrimes sin_m.sin_other = SIN_PROXY; 6331553Srgrimes else { 6341553Srgrimes rtm->rtm_addrs |= RTA_NETMASK; 6351553Srgrimes rtm->rtm_flags &= ~RTF_HOST; 6361553Srgrimes } 6371553Srgrimes } 6381553Srgrimes /* FALLTHROUGH */ 6391553Srgrimes case RTM_GET: 6401553Srgrimes rtm->rtm_addrs |= RTA_DST; 6411553Srgrimes } 6421553Srgrimes#define NEXTADDR(w, s) \ 6431553Srgrimes if (rtm->rtm_addrs & (w)) { \ 64451250Sru bcopy((char *)&s, cp, sizeof(s)); cp += ROUNDUP(sizeof(s));} 6451553Srgrimes 6461553Srgrimes NEXTADDR(RTA_DST, sin_m); 6471553Srgrimes NEXTADDR(RTA_GATEWAY, sdl_m); 6481553Srgrimes NEXTADDR(RTA_NETMASK, so_mask); 6491553Srgrimes 6501553Srgrimes rtm->rtm_msglen = cp - (char *)&m_rtmsg; 6511553Srgrimesdoit: 6521553Srgrimes l = rtm->rtm_msglen; 6531553Srgrimes rtm->rtm_seq = ++seq; 6541553Srgrimes rtm->rtm_type = cmd; 6551553Srgrimes if ((rlen = write(s, (char *)&m_rtmsg, l)) < 0) { 6561553Srgrimes if (errno != ESRCH || cmd != RTM_DELETE) { 65729060Scharnier warn("writing to routing socket"); 6581553Srgrimes return (-1); 6591553Srgrimes } 6601553Srgrimes } 6611553Srgrimes do { 6621553Srgrimes l = read(s, (char *)&m_rtmsg, sizeof(m_rtmsg)); 6631553Srgrimes } while (l > 0 && (rtm->rtm_seq != seq || rtm->rtm_pid != pid)); 6641553Srgrimes if (l < 0) 66529060Scharnier warn("read from routing socket"); 6661553Srgrimes return (0); 6671553Srgrimes} 6681553Srgrimes 66913977Sphk/* 67013977Sphk * get_ether_addr - get the hardware address of an interface on the 67113977Sphk * the same subnet as ipaddr. 67213977Sphk */ 67313977Sphk#define MAX_IFS 32 67413977Sphk 67513977Sphkint 67657727Sshinget_ether_addr(u_int32_t ipaddr, u_char *hwaddr) 67713977Sphk{ 67813977Sphk struct ifreq *ifr, *ifend, *ifp; 67957727Sshin u_int32_t ina, mask; 68013977Sphk struct sockaddr_dl *dla; 68113977Sphk struct ifreq ifreq; 68213977Sphk struct ifconf ifc; 68313977Sphk struct ifreq ifs[MAX_IFS]; 68487598Smikeh int sock; 68513977Sphk 68687598Smikeh sock = socket(AF_INET, SOCK_DGRAM, 0); 68787598Smikeh if (sock < 0) 68829060Scharnier err(1, "socket"); 68913977Sphk 69013977Sphk ifc.ifc_len = sizeof(ifs); 69113977Sphk ifc.ifc_req = ifs; 69292735Smikeh if (ioctl(sock, SIOCGIFCONF, &ifc) < 0) { 69329060Scharnier warnx("ioctl(SIOCGIFCONF)"); 69487598Smikeh close(sock); 69513977Sphk return 0; 69613977Sphk } 69713977Sphk 69813977Sphk /* 69913977Sphk * Scan through looking for an interface with an Internet 70013977Sphk * address on the same subnet as `ipaddr'. 70113977Sphk */ 70213977Sphk ifend = (struct ifreq *) (ifc.ifc_buf + ifc.ifc_len); 70313977Sphk for (ifr = ifc.ifc_req; ifr < ifend; ) { 70413977Sphk if (ifr->ifr_addr.sa_family == AF_INET) { 70513977Sphk ina = ((struct sockaddr_in *) 70613977Sphk &ifr->ifr_addr)->sin_addr.s_addr; 70713977Sphk strncpy(ifreq.ifr_name, ifr->ifr_name, 70813977Sphk sizeof(ifreq.ifr_name)); 70913977Sphk /* 71013977Sphk * Check that the interface is up, 71113977Sphk * and not point-to-point or loopback. 71213977Sphk */ 71392735Smikeh if (ioctl(sock, SIOCGIFFLAGS, &ifreq) < 0) 71413977Sphk continue; 71513977Sphk if ((ifreq.ifr_flags & 71613977Sphk (IFF_UP|IFF_BROADCAST|IFF_POINTOPOINT| 71713977Sphk IFF_LOOPBACK|IFF_NOARP)) 71813977Sphk != (IFF_UP|IFF_BROADCAST)) 71913977Sphk goto nextif; 72013977Sphk /* 72113977Sphk * Get its netmask and check that it's on 72213977Sphk * the right subnet. 72313977Sphk */ 72492735Smikeh if (ioctl(sock, SIOCGIFNETMASK, &ifreq) < 0) 72513977Sphk continue; 72613977Sphk mask = ((struct sockaddr_in *) 72713977Sphk &ifreq.ifr_addr)->sin_addr.s_addr; 72813977Sphk if ((ipaddr & mask) != (ina & mask)) 72913977Sphk goto nextif; 73013977Sphk break; 73113977Sphk } 73213977Sphknextif: 73347753Sarchie ifr = (struct ifreq *) ((char *)&ifr->ifr_addr 73447753Sarchie + MAX(ifr->ifr_addr.sa_len, sizeof(ifr->ifr_addr))); 73513977Sphk } 73613977Sphk 73713977Sphk if (ifr >= ifend) { 73887598Smikeh close(sock); 73913977Sphk return 0; 74013977Sphk } 74113977Sphk 74213977Sphk /* 74313977Sphk * Now scan through again looking for a link-level address 74413977Sphk * for this interface. 74513977Sphk */ 74613977Sphk ifp = ifr; 74713977Sphk for (ifr = ifc.ifc_req; ifr < ifend; ) { 74813977Sphk if (strcmp(ifp->ifr_name, ifr->ifr_name) == 0 74913977Sphk && ifr->ifr_addr.sa_family == AF_LINK) { 75013977Sphk /* 75113977Sphk * Found the link-level address - copy it out 75213977Sphk */ 75313977Sphk dla = (struct sockaddr_dl *) &ifr->ifr_addr; 75413977Sphk memcpy(hwaddr, LLADDR(dla), dla->sdl_alen); 75592735Smikeh close (sock); 75613977Sphk printf("using interface %s for proxy with address ", 75713977Sphk ifp->ifr_name); 75813977Sphk ether_print(hwaddr); 75913977Sphk printf("\n"); 76013977Sphk return dla->sdl_alen; 76113977Sphk } 76247753Sarchie ifr = (struct ifreq *) ((char *)&ifr->ifr_addr 76347753Sarchie + MAX(ifr->ifr_addr.sa_len, sizeof(ifr->ifr_addr))); 76413977Sphk } 76513977Sphk return 0; 76613977Sphk} 767