diff --git a/usr.sbin/arp/arp.c b/usr.sbin/arp/arp.c index 02b2bb1ac4f8..9a19d792f788 100644 --- a/usr.sbin/arp/arp.c +++ b/usr.sbin/arp/arp.c @@ -1,906 +1,902 @@ /*- * SPDX-License-Identifier: BSD-3-Clause * * Copyright (c) 1984, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * Sun Microsystems, Inc. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #if 0 #ifndef lint static char const copyright[] = "@(#) Copyright (c) 1984, 1993\n\ The Regents of the University of California. All rights reserved.\n"; #endif /* not lint */ #ifndef lint static char const sccsid[] = "@(#)from: arp.c 8.2 (Berkeley) 1/2/94"; #endif /* not lint */ #endif #include /* * arp - display, set, and delete arp table entries */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "arp.h" typedef void (action_fn)(struct sockaddr_dl *sdl, struct sockaddr_in *s_in, struct rt_msghdr *rtm); static void nuke_entries(uint32_t ifindex, struct in_addr addr); static int print_entries(uint32_t ifindex, struct in_addr addr); static int delete(char *host); static void usage(void) __dead2; static int set(int argc, char **argv); static int get(char *host); static int file(char *name); static struct rt_msghdr *rtmsg(int cmd, struct sockaddr_in *dst, struct sockaddr_dl *sdl); static int get_ether_addr(in_addr_t ipaddr, struct ether_addr *hwaddr); static int set_rtsock(struct sockaddr_in *dst, struct sockaddr_dl *sdl_m, char *host); -static char *rifname; - struct if_nameindex *ifnameindex; struct arp_opts opts = {}; /* which function we're supposed to do */ #define F_GET 1 #define F_SET 2 #define F_FILESET 3 #define F_REPLACE 4 #define F_DELETE 5 #define SETFUNC(f) { if (func) usage(); func = (f); } #define ARP_XO_VERSION "1" int main(int argc, char *argv[]) { int ch, func = 0; int rtn = 0; argc = xo_parse_args(argc, argv); if (argc < 0) exit(1); while ((ch = getopt(argc, argv, "andfsSi:")) != -1) switch(ch) { case 'a': opts.aflag = true; break; case 'd': SETFUNC(F_DELETE); break; case 'n': opts.nflag = true; break; case 'S': SETFUNC(F_REPLACE); break; case 's': SETFUNC(F_SET); break; case 'f' : SETFUNC(F_FILESET); break; case 'i': - rifname = optarg; + opts.rifname = optarg; break; case '?': default: usage(); } argc -= optind; argv += optind; if (!func) func = F_GET; - if (rifname) { + if (opts.rifname) { if (func != F_GET && !(func == F_DELETE && opts.aflag)) xo_errx(1, "-i not applicable to this operation"); - if (if_nametoindex(rifname) == 0) { + if ((opts.rifindex = if_nametoindex(opts.rifname)) == 0) { if (errno == ENXIO) xo_errx(1, "interface %s does not exist", - rifname); + opts.rifname); else - xo_err(1, "if_nametoindex(%s)", rifname); + xo_err(1, "if_nametoindex(%s)", opts.rifname); } } switch (func) { case F_GET: if (opts.aflag) { if (argc != 0) usage(); xo_set_version(ARP_XO_VERSION); xo_open_container("arp"); xo_open_list("arp-cache"); struct in_addr all_addrs = {}; - print_entries(0, all_addrs); + print_entries(opts.rifindex, all_addrs); xo_close_list("arp-cache"); xo_close_container("arp"); xo_finish(); } else { if (argc != 1) usage(); rtn = get(argv[0]); } break; case F_SET: case F_REPLACE: if (argc < 2 || argc > 6) usage(); if (func == F_REPLACE) (void)delete(argv[0]); rtn = set(argc, argv) ? 1 : 0; break; case F_DELETE: if (opts.aflag) { if (argc != 0) usage(); struct in_addr all_addrs = {}; nuke_entries(0, all_addrs); } else { if (argc != 1) usage(); rtn = delete(argv[0]); } break; case F_FILESET: if (argc != 1) usage(); rtn = file(argv[0]); break; } if (ifnameindex != NULL) if_freenameindex(ifnameindex); return (rtn); } /* * Process a file to set standard arp entries */ static int file(char *name) { FILE *fp; int i, retval; char line[100], arg[5][50], *args[5], *p; if ((fp = fopen(name, "r")) == NULL) xo_err(1, "cannot open %s", name); args[0] = &arg[0][0]; args[1] = &arg[1][0]; args[2] = &arg[2][0]; args[3] = &arg[3][0]; args[4] = &arg[4][0]; retval = 0; while(fgets(line, sizeof(line), fp) != NULL) { if ((p = strchr(line, '#')) != NULL) *p = '\0'; for (p = line; isblank(*p); p++); if (*p == '\n' || *p == '\0') continue; i = sscanf(p, "%49s %49s %49s %49s %49s", arg[0], arg[1], arg[2], arg[3], arg[4]); if (i < 2) { xo_warnx("bad line: %s", line); retval = 1; continue; } if (set(i, args)) retval = 1; } fclose(fp); return (retval); } /* * Given a hostname, fills up a (static) struct sockaddr_in with * the address of the host and returns a pointer to the * structure. */ struct sockaddr_in * getaddr(char *host) { struct hostent *hp; static struct sockaddr_in reply; bzero(&reply, sizeof(reply)); reply.sin_len = sizeof(reply); reply.sin_family = AF_INET; reply.sin_addr.s_addr = inet_addr(host); if (reply.sin_addr.s_addr == INADDR_NONE) { if (!(hp = gethostbyname(host))) { xo_warnx("%s: %s", host, hstrerror(h_errno)); return (NULL); } bcopy((char *)hp->h_addr, (char *)&reply.sin_addr, sizeof reply.sin_addr); } return (&reply); } int valid_type(int type); /* * Returns true if the type is a valid one for ARP. */ int valid_type(int type) { switch (type) { case IFT_ETHER: case IFT_FDDI: case IFT_IEEE1394: case IFT_INFINIBAND: case IFT_ISO88023: case IFT_ISO88024: case IFT_L2VLAN: case IFT_BRIDGE: return (1); default: return (0); } } /* * Set an individual arp entry */ static int set(int argc, char **argv) { struct sockaddr_in *dst; /* what are we looking for */ struct ether_addr *ea; char *host = argv[0], *eaddr = argv[1]; struct sockaddr_dl sdl_m; argc -= 2; argv += 2; bzero(&sdl_m, sizeof(sdl_m)); sdl_m.sdl_len = sizeof(sdl_m); sdl_m.sdl_family = AF_LINK; dst = getaddr(host); if (dst == NULL) return (1); while (argc-- > 0) { if (strcmp(argv[0], "temp") == 0) { int max_age; size_t len = sizeof(max_age); if (sysctlbyname("net.link.ether.inet.max_age", &max_age, &len, NULL, 0) != 0) xo_err(1, "sysctlbyname"); opts.expire_time = max_age; } else if (strcmp(argv[0], "pub") == 0) { opts.flags |= RTF_ANNOUNCE; if (argc && strcmp(argv[1], "only") == 0) { /* * Compatibility: in pre FreeBSD 8 times * the "only" keyword used to mean that * an ARP entry should be announced, but * not installed into routing table. */ argc--; argv++; } } else if (strcmp(argv[0], "blackhole") == 0) { if (opts.flags & RTF_REJECT) { xo_errx(1, "Choose one of blackhole or reject, " "not both."); } opts.flags |= RTF_BLACKHOLE; } else if (strcmp(argv[0], "reject") == 0) { if (opts.flags & RTF_BLACKHOLE) { xo_errx(1, "Choose one of blackhole or reject, " "not both."); } opts.flags |= RTF_REJECT; } else { xo_warnx("Invalid parameter '%s'", argv[0]); usage(); } argv++; } ea = (struct ether_addr *)LLADDR(&sdl_m); if ((opts.flags & RTF_ANNOUNCE) && !strcmp(eaddr, "auto")) { if (!get_ether_addr(dst->sin_addr.s_addr, ea)) { xo_warnx("no interface found for %s", inet_ntoa(dst->sin_addr)); return (1); } sdl_m.sdl_alen = ETHER_ADDR_LEN; } else { struct ether_addr *ea1 = ether_aton(eaddr); if (ea1 == NULL) { xo_warnx("invalid Ethernet address '%s'", eaddr); return (1); } else { *ea = *ea1; sdl_m.sdl_alen = ETHER_ADDR_LEN; } } #ifndef WITHOUT_NETLINK return (set_nl(0, dst, &sdl_m, host)); #else return (set_rtsock(dst, &sdl_m, host)); #endif } #ifdef WITHOUT_NETLINK static int set_rtsock(struct sockaddr_in *dst, struct sockaddr_dl *sdl_m, char *host) { struct sockaddr_in *addr; struct sockaddr_dl *sdl; struct rt_msghdr *rtm; /* * In the case a proxy-arp entry is being added for * a remote end point, the RTF_ANNOUNCE flag in the * RTM_GET command is an indication to the kernel * routing code that the interface associated with * the prefix route covering the local end of the * PPP link should be returned, on which ARP applies. */ rtm = rtmsg(RTM_GET, dst, NULL); if (rtm == NULL) { xo_warn("%s", host); return (1); } addr = (struct sockaddr_in *)(rtm + 1); sdl = (struct sockaddr_dl *)(SA_SIZE(addr) + (char *)addr); if ((sdl->sdl_family != AF_LINK) || (rtm->rtm_flags & RTF_GATEWAY) || !valid_type(sdl->sdl_type)) { xo_warnx("cannot intuit interface index and type for %s", host); return (1); } sdl_m->sdl_type = sdl->sdl_type; sdl_m->sdl_index = sdl->sdl_index; return (rtmsg(RTM_ADD, dst, sdl_m) == NULL); } #endif /* * Display an individual arp entry */ static int get(char *host) { struct sockaddr_in *addr; int found; addr = getaddr(host); if (addr == NULL) return (1); xo_set_version(ARP_XO_VERSION); xo_open_container("arp"); xo_open_list("arp-cache"); - found = print_entries(0, addr->sin_addr); + found = print_entries(opts.rifindex, addr->sin_addr); if (found == 0) { xo_emit("{d:hostname/%s} ({d:ip-address/%s}) -- no entry", host, inet_ntoa(addr->sin_addr)); - if (rifname) - xo_emit(" on {d:interface/%s}", rifname); + if (opts.rifname) + xo_emit(" on {d:interface/%s}", opts.rifname); xo_emit("\n"); } xo_close_list("arp-cache"); xo_close_container("arp"); xo_finish(); return (found == 0); } /* * Delete an arp entry */ #ifdef WITHOUT_NETLINK static int delete_rtsock(char *host) { struct sockaddr_in *addr, *dst; struct rt_msghdr *rtm; struct sockaddr_dl *sdl; dst = getaddr(host); if (dst == NULL) return (1); /* * Perform a regular entry delete first. */ opts.flags &= ~RTF_ANNOUNCE; for (;;) { /* try twice */ rtm = rtmsg(RTM_GET, dst, NULL); if (rtm == NULL) { xo_warn("%s", host); return (1); } addr = (struct sockaddr_in *)(rtm + 1); sdl = (struct sockaddr_dl *)(SA_SIZE(addr) + (char *)addr); /* * With the new L2/L3 restructure, the route * returned is a prefix route. The important * piece of information from the previous * RTM_GET is the interface index. In the * case of ECMP, the kernel will traverse * the route group for the given entry. */ if (sdl->sdl_family == AF_LINK && !(rtm->rtm_flags & RTF_GATEWAY) && valid_type(sdl->sdl_type) ) { addr->sin_addr.s_addr = dst->sin_addr.s_addr; break; } /* * Regular entry delete failed, now check if there * is a proxy-arp entry to remove. */ if (opts.flags & RTF_ANNOUNCE) { xo_warnx("delete: cannot locate %s", host); return (1); } opts.flags |= RTF_ANNOUNCE; } rtm->rtm_flags |= RTF_LLDATA; if (rtmsg(RTM_DELETE, dst, NULL) != NULL) { printf("%s (%s) deleted\n", host, inet_ntoa(addr->sin_addr)); return (0); } return (1); } #endif static int delete(char *host) { #ifdef WITHOUT_NETLINK return (delete_rtsock(host)); #else return (delete_nl(0, host)); #endif } /* * Search the arp table and do some action on matching entries */ static int search(u_long addr, action_fn *action) { int mib[6]; size_t needed; char *lim, *buf, *next; struct rt_msghdr *rtm; struct sockaddr_in *sin2; struct sockaddr_dl *sdl; - char ifname[IF_NAMESIZE]; int st, found_entry = 0; mib[0] = CTL_NET; mib[1] = PF_ROUTE; mib[2] = 0; mib[3] = AF_INET; mib[4] = NET_RT_FLAGS; #ifdef RTF_LLINFO mib[5] = RTF_LLINFO; #else mib[5] = 0; #endif if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0) xo_err(1, "route-sysctl-estimate"); if (needed == 0) /* empty table */ return 0; buf = NULL; for (;;) { buf = reallocf(buf, needed); if (buf == NULL) xo_errx(1, "could not reallocate memory"); st = sysctl(mib, 6, buf, &needed, NULL, 0); if (st == 0 || errno != ENOMEM) break; needed += needed / 8; } if (st == -1) xo_err(1, "actual retrieval of routing table"); lim = buf + needed; for (next = buf; next < lim; next += rtm->rtm_msglen) { rtm = (struct rt_msghdr *)next; sin2 = (struct sockaddr_in *)(rtm + 1); sdl = (struct sockaddr_dl *)((char *)sin2 + SA_SIZE(sin2)); - if (rifname && if_indextoname(sdl->sdl_index, ifname) && - strcmp(ifname, rifname)) + if (opts.rifindex && + (opts.rifindex != sdl->sdl_index)) continue; - if (addr) { - if (addr != sin2->sin_addr.s_addr) - continue; - found_entry = 1; - } + if (addr && + (addr != sin2->sin_addr.s_addr)) + continue; + found_entry = 1; (*action)(sdl, sin2, rtm); } free(buf); return (found_entry); } /* * Display an arp entry */ static void print_entry(struct sockaddr_dl *sdl, struct sockaddr_in *addr, struct rt_msghdr *rtm) { const char *host; struct hostent *hp; struct if_nameindex *p; if (ifnameindex == NULL) if ((ifnameindex = if_nameindex()) == NULL) xo_err(1, "cannot retrieve interface names"); xo_open_instance("arp-cache"); if (!opts.nflag) hp = gethostbyaddr((caddr_t)&(addr->sin_addr), sizeof addr->sin_addr, AF_INET); else hp = 0; if (hp) host = hp->h_name; else { host = "?"; if (h_errno == TRY_AGAIN) opts.nflag = true; } xo_emit("{:hostname/%s} ({:ip-address/%s}) at ", host, inet_ntoa(addr->sin_addr)); if (sdl->sdl_alen) { if ((sdl->sdl_type == IFT_ETHER || sdl->sdl_type == IFT_L2VLAN || sdl->sdl_type == IFT_BRIDGE) && sdl->sdl_alen == ETHER_ADDR_LEN) xo_emit("{:mac-address/%s}", ether_ntoa((struct ether_addr *)LLADDR(sdl))); else { int n = sdl->sdl_nlen > 0 ? sdl->sdl_nlen + 1 : 0; xo_emit("{:mac-address/%s}", link_ntoa(sdl) + n); } } else xo_emit("{d:/(incomplete)}{en:incomplete/true}"); for (p = ifnameindex; p && p->if_index && p->if_name; p++) { if (p->if_index == sdl->sdl_index) { xo_emit(" on {:interface/%s}", p->if_name); break; } } if (rtm->rtm_rmx.rmx_expire == 0) xo_emit("{d:/ permanent}{en:permanent/true}"); else { static struct timespec tp; time_t expire_time = 0; if (tp.tv_sec == 0) clock_gettime(CLOCK_MONOTONIC, &tp); if ((expire_time = rtm->rtm_rmx.rmx_expire - tp.tv_sec) > 0) xo_emit(" expires in {:expires/%d} seconds", (int)expire_time); else xo_emit("{d:/ expired}{en:expired/true}"); } if (rtm->rtm_flags & RTF_ANNOUNCE) xo_emit("{d:/ published}{en:published/true}"); switch(sdl->sdl_type) { case IFT_ETHER: xo_emit(" [{:type/ethernet}]"); break; case IFT_FDDI: xo_emit(" [{:type/fddi}]"); break; case IFT_ATM: xo_emit(" [{:type/atm}]"); break; case IFT_L2VLAN: xo_emit(" [{:type/vlan}]"); break; case IFT_IEEE1394: xo_emit(" [{:type/firewire}]"); break; case IFT_BRIDGE: xo_emit(" [{:type/bridge}]"); break; case IFT_INFINIBAND: xo_emit(" [{:type/infiniband}]"); break; default: break; } xo_emit("\n"); xo_close_instance("arp-cache"); } static int print_entries(uint32_t ifindex, struct in_addr addr) { #ifndef WITHOUT_NETLINK return (print_entries_nl(ifindex, addr)); #else return (search(addr.s_addr, print_entry)); #endif } /* * Nuke an arp entry */ static void nuke_entry(struct sockaddr_dl *sdl __unused, struct sockaddr_in *addr, struct rt_msghdr *rtm) { char ip[20]; if (rtm->rtm_flags & RTF_PINNED) return; snprintf(ip, sizeof(ip), "%s", inet_ntoa(addr->sin_addr)); delete(ip); } static void nuke_entries(uint32_t ifindex, struct in_addr addr) { search(addr.s_addr, nuke_entry); } static void usage(void) { fprintf(stderr, "%s\n%s\n%s\n%s\n%s\n%s\n%s\n", "usage: arp [-n] [-i interface] hostname", " arp [-n] [-i interface] -a", " arp -d hostname [pub]", " arp -d [-i interface] -a", " arp -s hostname ether_addr [temp] [reject | blackhole] [pub [only]]", " arp -S hostname ether_addr [temp] [reject | blackhole] [pub [only]]", " arp -f filename"); exit(1); } static struct rt_msghdr * rtmsg(int cmd, struct sockaddr_in *dst, struct sockaddr_dl *sdl) { static int seq; int rlen; int l; static int s = -1; static pid_t pid; static struct { struct rt_msghdr m_rtm; char m_space[512]; } m_rtmsg; struct rt_msghdr *rtm = &m_rtmsg.m_rtm; char *cp = m_rtmsg.m_space; if (s < 0) { /* first time: open socket, get pid */ s = socket(PF_ROUTE, SOCK_RAW, 0); if (s < 0) xo_err(1, "socket"); pid = getpid(); } errno = 0; /* * XXX RTM_DELETE relies on a previous RTM_GET to fill the buffer * appropriately. */ if (cmd == RTM_DELETE) goto doit; bzero((char *)&m_rtmsg, sizeof(m_rtmsg)); rtm->rtm_flags = opts.flags; rtm->rtm_version = RTM_VERSION; switch (cmd) { default: xo_errx(1, "internal wrong cmd"); case RTM_ADD: rtm->rtm_addrs |= RTA_GATEWAY; if (opts.expire_time != 0) { struct timespec tp; clock_gettime(CLOCK_MONOTONIC, &tp); rtm->rtm_rmx.rmx_expire = opts.expire_time + tp.tv_sec; } rtm->rtm_inits = RTV_EXPIRE; rtm->rtm_flags |= (RTF_HOST | RTF_STATIC | RTF_LLDATA); /* FALLTHROUGH */ case RTM_GET: rtm->rtm_addrs |= RTA_DST; } #define NEXTADDR(w, s) \ do { \ if ((s) != NULL && rtm->rtm_addrs & (w)) { \ bcopy((s), cp, sizeof(*(s))); \ cp += SA_SIZE(s); \ } \ } while (0) NEXTADDR(RTA_DST, dst); NEXTADDR(RTA_GATEWAY, sdl); rtm->rtm_msglen = cp - (char *)&m_rtmsg; doit: l = rtm->rtm_msglen; rtm->rtm_seq = ++seq; rtm->rtm_type = cmd; if ((rlen = write(s, (char *)&m_rtmsg, l)) < 0) { if (errno != ESRCH || cmd != RTM_DELETE) { xo_warn("writing to routing socket"); return (NULL); } } do { l = read(s, (char *)&m_rtmsg, sizeof(m_rtmsg)); } while (l > 0 && (rtm->rtm_type != cmd || rtm->rtm_seq != seq || rtm->rtm_pid != pid)); if (l < 0) xo_warn("read from routing socket"); return (rtm); } /* * get_ether_addr - get the hardware address of an interface on the * the same subnet as ipaddr. */ static int get_ether_addr(in_addr_t ipaddr, struct ether_addr *hwaddr) { struct ifaddrs *ifa, *ifd, *ifas = NULL; in_addr_t ina, mask; struct sockaddr_dl *dla; int retval = 0; /* * Scan through looking for an interface with an Internet * address on the same subnet as `ipaddr'. */ if (getifaddrs(&ifas) < 0) { xo_warnx("getifaddrs"); goto done; } for (ifa = ifas; ifa != NULL; ifa = ifa->ifa_next) { if (ifa->ifa_addr == NULL || ifa->ifa_netmask == NULL) continue; if (ifa->ifa_addr->sa_family != AF_INET) continue; /* * Check that the interface is up, * and not point-to-point or loopback. */ if ((ifa->ifa_flags & (IFF_UP|IFF_BROADCAST|IFF_POINTOPOINT| IFF_LOOPBACK|IFF_NOARP)) != (IFF_UP|IFF_BROADCAST)) continue; /* Get its netmask and check that it's on the right subnet. */ mask = ((struct sockaddr_in *) ifa->ifa_netmask)->sin_addr.s_addr; ina = ((struct sockaddr_in *) ifa->ifa_addr)->sin_addr.s_addr; if ((ipaddr & mask) == (ina & mask)) break; /* ok, we got it! */ } if (ifa == NULL) goto done; /* * Now scan through again looking for a link-level address * for this interface. */ for (ifd = ifas; ifd != NULL; ifd = ifd->ifa_next) { if (ifd->ifa_addr == NULL) continue; if (strcmp(ifa->ifa_name, ifd->ifa_name) == 0 && ifd->ifa_addr->sa_family == AF_LINK) break; } if (ifd == NULL) goto done; /* * Found the link-level address - copy it out */ dla = (struct sockaddr_dl *)ifd->ifa_addr; memcpy(hwaddr, LLADDR(dla), dla->sdl_alen); printf("using interface %s for proxy with address %s\n", ifa->ifa_name, ether_ntoa(hwaddr)); retval = dla->sdl_alen; done: if (ifas != NULL) freeifaddrs(ifas); return (retval); } diff --git a/usr.sbin/arp/arp.h b/usr.sbin/arp/arp.h index a7de3a1a3024..487863be43e7 100644 --- a/usr.sbin/arp/arp.h +++ b/usr.sbin/arp/arp.h @@ -1,21 +1,23 @@ #ifndef _USR_SBIN_ARP_ARP_H_ #define _USR_SBIN_ARP_ARP_H_ int valid_type(int type); struct sockaddr_in *getaddr(char *host); int print_entries_nl(uint32_t ifindex, struct in_addr addr); struct arp_opts { bool aflag; bool nflag; time_t expire_time; int flags; + char *rifname; + unsigned int rifindex; }; extern struct arp_opts opts; int print_entries_nl(uint32_t ifindex, struct in_addr addr); int delete_nl(uint32_t ifindex, char *host); int set_nl(uint32_t ifindex, struct sockaddr_in *dst, struct sockaddr_dl *sdl, char *host); #endif diff --git a/usr.sbin/arp/arp_netlink.c b/usr.sbin/arp/arp_netlink.c index 4e5c8f3d9940..40b5367f330d 100644 --- a/usr.sbin/arp/arp_netlink.c +++ b/usr.sbin/arp/arp_netlink.c @@ -1,434 +1,442 @@ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "arp.h" #define RTF_ANNOUNCE RTF_PROTO2 static void nl_init_socket(struct snl_state *ss) { if (snl_init(ss, NETLINK_ROUTE)) return; if (modfind("netlink") == -1 && errno == ENOENT) { /* Try to load */ if (kldload("netlink") == -1) err(1, "netlink is not loaded and load attempt failed"); if (snl_init(ss, NETLINK_ROUTE)) return; } err(1, "unable to open netlink socket"); } static bool get_link_info(struct snl_state *ss, uint32_t ifindex, struct snl_parsed_link_simple *link) { struct snl_writer nw; snl_init_writer(ss, &nw); struct nlmsghdr *hdr = snl_create_msg_request(&nw, RTM_GETLINK); struct ifinfomsg *ifmsg = snl_reserve_msg_object(&nw, struct ifinfomsg); if (ifmsg != NULL) ifmsg->ifi_index = ifindex; if (!snl_finalize_msg(&nw) || !snl_send_message(ss, hdr)) return (false); hdr = snl_read_reply(ss, hdr->nlmsg_seq); if (hdr == NULL || hdr->nlmsg_type != RTM_NEWLINK) return (false); if (!snl_parse_nlmsg(ss, hdr, &snl_rtm_link_parser_simple, link)) return (false); return (true); } static bool has_l2(struct snl_state *ss, uint32_t ifindex) { struct snl_parsed_link_simple link = {}; if (!get_link_info(ss, ifindex, &link)) return (false); return (valid_type(link.ifi_type) != 0); } static uint32_t get_myfib(void) { uint32_t fibnum = 0; size_t len = sizeof(fibnum); sysctlbyname("net.my_fibnum", (void *)&fibnum, &len, NULL, 0); return (fibnum); } static int guess_ifindex(struct snl_state *ss, uint32_t fibnum, struct in_addr addr) { struct snl_writer nw; snl_init_writer(ss, &nw); struct nlmsghdr *hdr = snl_create_msg_request(&nw, RTM_GETROUTE); struct rtmsg *rtm = snl_reserve_msg_object(&nw, struct rtmsg); rtm->rtm_family = AF_INET; struct sockaddr_in dst = { .sin_family = AF_INET, .sin_addr = addr }; snl_add_msg_attr_ip(&nw, RTA_DST, (struct sockaddr *)&dst); snl_add_msg_attr_u32(&nw, RTA_TABLE, fibnum); if (!snl_finalize_msg(&nw) || !snl_send_message(ss, hdr)) return (0); hdr = snl_read_reply(ss, hdr->nlmsg_seq); if (hdr->nlmsg_type != NL_RTM_NEWROUTE) { /* No route found, unable to guess ifindex */ return (0); } struct snl_parsed_route r = {}; if (!snl_parse_nlmsg(ss, hdr, &snl_rtm_route_parser, &r)) return (0); if (r.rta_multipath.num_nhops > 0 || (r.rta_rtflags & RTF_GATEWAY)) return (0); /* Check if the interface is of supported type */ if (has_l2(ss, r.rta_oif)) return (r.rta_oif); /* Check the case when we matched the loopback route for P2P */ snl_init_writer(ss, &nw); hdr = snl_create_msg_request(&nw, RTM_GETNEXTHOP); snl_reserve_msg_object(&nw, struct nhmsg); int off = snl_add_msg_attr_nested(&nw, NHA_FREEBSD); snl_add_msg_attr_u32(&nw, NHAF_KID, r.rta_knh_id); snl_add_msg_attr_u8(&nw, NHAF_FAMILY, AF_INET); snl_add_msg_attr_u32(&nw, NHAF_TABLE, fibnum); snl_end_attr_nested(&nw, off); if (!snl_finalize_msg(&nw) || !snl_send_message(ss, hdr)) return (0); hdr = snl_read_reply(ss, hdr->nlmsg_seq); if (hdr->nlmsg_type != NL_RTM_NEWNEXTHOP) { /* No nexthop found, unable to guess ifindex */ return (0); } struct snl_parsed_nhop nh = {}; if (!snl_parse_nlmsg(ss, hdr, &snl_nhmsg_parser, &nh)) return (0); return (nh.nhaf_aif); } static uint32_t fix_ifindex(struct snl_state *ss, uint32_t ifindex, struct in_addr addr) { if (ifindex == 0) ifindex = guess_ifindex(ss, get_myfib(), addr); return (ifindex); } static void print_entry(struct snl_parsed_neigh *neigh, struct snl_parsed_link_simple *link) { const char *host; struct hostent *hp; struct sockaddr_in *addr = (struct sockaddr_in *)neigh->nda_dst; xo_open_instance("arp-cache"); if (!opts.nflag) hp = gethostbyaddr((caddr_t)&(addr->sin_addr), sizeof(addr->sin_addr), AF_INET); else hp = 0; if (hp) host = hp->h_name; else { host = "?"; if (h_errno == TRY_AGAIN) opts.nflag = true; } xo_emit("{:hostname/%s} ({:ip-address/%s}) at ", host, inet_ntoa(addr->sin_addr)); if (neigh->nda_lladdr != NULL) { struct sockaddr_dl sdl = { .sdl_family = AF_LINK, .sdl_type = link->ifi_type, .sdl_len = sizeof(struct sockaddr_dl), .sdl_alen = NLA_DATA_LEN(neigh->nda_lladdr), }; memcpy(sdl.sdl_data, NLA_DATA(neigh->nda_lladdr), sdl.sdl_alen); if ((sdl.sdl_type == IFT_ETHER || sdl.sdl_type == IFT_L2VLAN || sdl.sdl_type == IFT_BRIDGE) && sdl.sdl_alen == ETHER_ADDR_LEN) xo_emit("{:mac-address/%s}", ether_ntoa((struct ether_addr *)LLADDR(&sdl))); else { xo_emit("{:mac-address/%s}", link_ntoa(&sdl)); } } else xo_emit("{d:/(incomplete)}{en:incomplete/true}"); xo_emit(" on {:interface/%s}", link->ifla_ifname); if (neigh->ndaf_next_ts == 0) xo_emit("{d:/ permanent}{en:permanent/true}"); else { time_t expire_time; struct timeval now; gettimeofday(&now, 0); if ((expire_time = neigh->ndaf_next_ts - now.tv_sec) > 0) xo_emit(" expires in {:expires/%d} seconds", (int)expire_time); else xo_emit("{d:/ expired}{en:expired/true}"); } if (neigh->ndm_flags & NTF_PROXY) xo_emit("{d:/ published}{en:published/true}"); switch(link->ifi_type) { case IFT_ETHER: xo_emit(" [{:type/ethernet}]"); break; case IFT_FDDI: xo_emit(" [{:type/fddi}]"); break; case IFT_ATM: xo_emit(" [{:type/atm}]"); break; case IFT_L2VLAN: xo_emit(" [{:type/vlan}]"); break; case IFT_IEEE1394: xo_emit(" [{:type/firewire}]"); break; case IFT_BRIDGE: xo_emit(" [{:type/bridge}]"); break; case IFT_INFINIBAND: xo_emit(" [{:type/infiniband}]"); break; default: break; } xo_emit("\n"); xo_close_instance("arp-cache"); } int print_entries_nl(uint32_t ifindex, struct in_addr addr) { struct snl_state ss_req = {}, ss_cmd = {}; struct snl_parsed_link_simple link = {}; struct snl_writer nw; nl_init_socket(&ss_req); snl_init_writer(&ss_req, &nw); struct nlmsghdr *hdr = snl_create_msg_request(&nw, RTM_GETNEIGH); struct ndmsg *ndmsg = snl_reserve_msg_object(&nw, struct ndmsg); if (ndmsg != NULL) { ndmsg->ndm_family = AF_INET; + /* let kernel filter results by interface if provided */ ndmsg->ndm_ifindex = ifindex; } if (!snl_finalize_msg(&nw) || !snl_send_message(&ss_req, hdr)) { snl_free(&ss_req); return (0); } uint32_t nlmsg_seq = hdr->nlmsg_seq; struct snl_errmsg_data e = {}; int count = 0; nl_init_socket(&ss_cmd); while ((hdr = snl_read_reply_multi(&ss_req, nlmsg_seq, &e)) != NULL) { struct snl_parsed_neigh neigh = {}; + struct sockaddr_in *neighaddr; if (!snl_parse_nlmsg(&ss_req, hdr, &snl_rtm_neigh_parser, &neigh)) continue; if (neigh.nda_ifindex != link.ifi_index) { snl_clear_lb(&ss_cmd); memset(&link, 0, sizeof(link)); if (!get_link_info(&ss_cmd, neigh.nda_ifindex, &link)) continue; } + /* filter results based on host if provided */ + neighaddr = (struct sockaddr_in *)neigh.nda_dst; + if (addr.s_addr && + (addr.s_addr != neighaddr->sin_addr.s_addr)) + continue; + print_entry(&neigh, &link); count++; snl_clear_lb(&ss_req); } snl_free(&ss_req); snl_free(&ss_cmd); return (count); } int delete_nl(uint32_t ifindex, char *host) { struct snl_state ss = {}; struct snl_writer nw; struct sockaddr_in *dst; dst = getaddr(host); if (dst == NULL) return (1); nl_init_socket(&ss); ifindex = fix_ifindex(&ss, ifindex, dst->sin_addr); if (ifindex == 0) { xo_warnx("delete: cannot locate %s", host); snl_free(&ss); return (0); } snl_init_writer(&ss, &nw); struct nlmsghdr *hdr = snl_create_msg_request(&nw, RTM_DELNEIGH); struct ndmsg *ndmsg = snl_reserve_msg_object(&nw, struct ndmsg); if (ndmsg != NULL) { ndmsg->ndm_family = AF_INET; ndmsg->ndm_ifindex = ifindex; } snl_add_msg_attr_ip(&nw, NDA_DST, (struct sockaddr *)dst); if (!snl_finalize_msg(&nw) || !snl_send_message(&ss, hdr)) { snl_free(&ss); return (1); } struct snl_errmsg_data e = {}; snl_read_reply_code(&ss, hdr->nlmsg_seq, &e); if (e.error != 0) { if (e.error_str != NULL) xo_warnx("delete %s: %s (%s)", host, strerror(e.error), e.error_str); else xo_warnx("delete %s: %s", host, strerror(e.error)); } else printf("%s (%s) deleted\n", host, inet_ntoa(dst->sin_addr)); snl_free(&ss); return (e.error != 0); } int set_nl(uint32_t ifindex, struct sockaddr_in *dst, struct sockaddr_dl *sdl, char *host) { struct snl_state ss = {}; struct snl_writer nw; nl_init_socket(&ss); ifindex = fix_ifindex(&ss, ifindex, dst->sin_addr); if (ifindex == 0) { xo_warnx("delete: cannot locate %s", host); snl_free(&ss); return (0); } if (opts.expire_time != 0) opts.flags &= ~RTF_STATIC; snl_init_writer(&ss, &nw); struct nlmsghdr *hdr = snl_create_msg_request(&nw, RTM_NEWNEIGH); hdr->nlmsg_flags |= NLM_F_CREATE | NLM_F_REPLACE; struct ndmsg *ndmsg = snl_reserve_msg_object(&nw, struct ndmsg); if (ndmsg != NULL) { uint8_t nl_flags = 0; ndmsg->ndm_family = AF_INET; ndmsg->ndm_ifindex = ifindex; ndmsg->ndm_state = (opts.flags & RTF_STATIC) ? NUD_PERMANENT : NUD_NONE; if (opts.flags & RTF_ANNOUNCE) nl_flags |= NTF_PROXY; if (opts.flags & RTF_STATIC) nl_flags |= NTF_STICKY; ndmsg->ndm_flags = nl_flags; } snl_add_msg_attr_ip(&nw, NDA_DST, (struct sockaddr *)dst); snl_add_msg_attr(&nw, NDA_LLADDR, sdl->sdl_alen, LLADDR(sdl)); if (opts.expire_time != 0) { struct timeval now; gettimeofday(&now, 0); int off = snl_add_msg_attr_nested(&nw, NDA_FREEBSD); snl_add_msg_attr_u32(&nw, NDAF_NEXT_STATE_TS, now.tv_sec + opts.expire_time); snl_end_attr_nested(&nw, off); } if (!snl_finalize_msg(&nw) || !snl_send_message(&ss, hdr)) { snl_free(&ss); return (1); } struct snl_errmsg_data e = {}; snl_read_reply_code(&ss, hdr->nlmsg_seq, &e); if (e.error != 0) { if (e.error_str != NULL) xo_warnx("set: %s: %s (%s)", host, strerror(e.error), e.error_str); else xo_warnx("set %s: %s", host, strerror(e.error)); } snl_free(&ss); return (e.error != 0); }