--- /dev/null
+/*
+ * arping.c - Ping hosts by ARP requests/replies
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ * Author: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
+ * Busybox port: Nick Fedchik <nick@fedchik.org.ua>
+ */
+
+#include <sys/ioctl.h>
+#include <sys/signal.h>
+#include <sys/time.h>
+
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <arpa/inet.h>
+#include <net/if.h>
+#include <netinet/ether.h>
+#include <netpacket/packet.h>
+
+#include "busybox.h"
+
+#define APPLET_NAME "arping"
+
+struct in_addr src;
+struct in_addr dst;
+struct sockaddr_ll me;
+struct sockaddr_ll he;
+struct timeval last;
+int dad;
+int unsolicited;
+int advert;
+int quiet;
+int quit_on_reply = 0;
+int count = -1;
+int timeout;
+int unicasting;
+int s;
+int broadcast_only;
+int sent;
+int brd_sent;
+int received;
+int brd_recv;
+int req_recv;
+
+#define MS_TDIFF(tv1,tv2) ( ((tv1).tv_sec-(tv2).tv_sec)*1000 + \
+ ((tv1).tv_usec-(tv2).tv_usec)/1000 )
+#if 0
+static void set_signal(int signo, void (*handler) (void))
+{
+ struct sigaction sa;
+
+ memset(&sa, 0, sizeof(sa));
+ sa.sa_handler = (void (*)(int)) handler;
+ sa.sa_flags = SA_RESTART;
+ sigaction(signo, &sa, NULL);
+}
+#endif
+
+static int send_pack(int sock, struct in_addr *src_addr, struct in_addr *dst_addr,
+ struct sockaddr_ll *ME, struct sockaddr_ll *HE)
+{
+ int err;
+ struct timeval now;
+ unsigned char buf[256];
+ struct arphdr *ah = (struct arphdr *) buf;
+ unsigned char *p = (unsigned char *) (ah + 1);
+
+ ah->ar_hrd = htons(ME->sll_hatype);
+ ah->ar_hrd = htons(ARPHRD_ETHER);
+ ah->ar_pro = htons(ETH_P_IP);
+ ah->ar_hln = ME->sll_halen;
+ ah->ar_pln = 4;
+ ah->ar_op = advert ? htons(ARPOP_REPLY) : htons(ARPOP_REQUEST);
+
+ memcpy(p, &ME->sll_addr, ah->ar_hln);
+ p += ME->sll_halen;
+
+ memcpy(p, src_addr, 4);
+ p += 4;
+
+ if (advert)
+ memcpy(p, &ME->sll_addr, ah->ar_hln);
+ else
+ memcpy(p, &HE->sll_addr, ah->ar_hln);
+ p += ah->ar_hln;
+
+ memcpy(p, dst_addr, 4);
+ p += 4;
+
+ gettimeofday(&now, NULL);
+ err = sendto(sock, buf, p - buf, 0, (struct sockaddr *) HE, sizeof(*HE));
+ if (err == p - buf) {
+ last = now;
+ sent++;
+ if (!unicasting)
+ brd_sent++;
+ }
+ return err;
+}
+
+void finish(void)
+{
+ if (!quiet) {
+ printf("Sent %d probes (%d broadcast(s))\n", sent, brd_sent);
+ printf("Received %d repl%s", received, (received > 1) ? "ies" : "y");
+ if (brd_recv || req_recv) {
+ printf(" (");
+ if (req_recv)
+ printf("%d request(s)", req_recv);
+ if (brd_recv)
+ printf("%s%d broadcast(s)", req_recv ? ", " : "", brd_recv);
+ putchar(')');
+ }
+ putchar('\n');
+ fflush(stdout);
+ }
+ if (dad)
+ exit(!!received);
+ if (unsolicited)
+ exit(0);
+ exit(!received);
+}
+
+void catcher(void)
+{
+ struct timeval tv;
+ struct timeval start;
+
+ gettimeofday(&tv, NULL);
+
+ if (start.tv_sec == 0)
+ start = tv;
+
+ if (count-- == 0
+ || (timeout && MS_TDIFF(tv, start) > timeout * 1000 + 500))
+ finish();
+
+ if (last.tv_sec == 0 || MS_TDIFF(tv, last) > 500) {
+ send_pack(s, &src, &dst, &me, &he);
+ if (count == 0 && unsolicited)
+ finish();
+ }
+ alarm(1);
+}
+
+int recv_pack(unsigned char *buf, int len, struct sockaddr_ll *FROM)
+{
+ struct timeval tv;
+ struct arphdr *ah = (struct arphdr *) buf;
+ unsigned char *p = (unsigned char *) (ah + 1);
+ struct in_addr src_ip, dst_ip;
+
+ gettimeofday(&tv, NULL);
+
+ /* Filter out wild packets */
+ if (FROM->sll_pkttype != PACKET_HOST &&
+ FROM->sll_pkttype != PACKET_BROADCAST &&
+ FROM->sll_pkttype != PACKET_MULTICAST)
+ return 0;
+
+ /* Only these types are recognised */
+ if (ah->ar_op != htons(ARPOP_REQUEST) && ah->ar_op != htons(ARPOP_REPLY))
+ return 0;
+
+ /* ARPHRD check and this darned FDDI hack here :-( */
+ if (ah->ar_hrd != htons(FROM->sll_hatype) &&
+ (FROM->sll_hatype != ARPHRD_FDDI
+ || ah->ar_hrd != htons(ARPHRD_ETHER)))
+ return 0;
+
+ /* Protocol must be IP. */
+ if (ah->ar_pro != htons(ETH_P_IP))
+ return 0;
+ if (ah->ar_pln != 4)
+ return 0;
+ if (ah->ar_hln != me.sll_halen)
+ return 0;
+ if (len < sizeof(*ah) + 2 * (4 + ah->ar_hln))
+ return 0;
+ memcpy(&src_ip, p + ah->ar_hln, 4);
+ memcpy(&dst_ip, p + ah->ar_hln + 4 + ah->ar_hln, 4);
+ if (!dad) {
+ if (src_ip.s_addr != dst.s_addr)
+ return 0;
+ if (src.s_addr != dst_ip.s_addr)
+ return 0;
+ if (memcmp(p + ah->ar_hln + 4, &me.sll_addr, ah->ar_hln))
+ return 0;
+ } else {
+ /* DAD packet was:
+ src_ip = 0 (or some src)
+ src_hw = ME
+ dst_ip = tested address
+ dst_hw = <unspec>
+
+ We fail, if receive request/reply with:
+ src_ip = tested_address
+ src_hw != ME
+ if src_ip in request was not zero, check
+ also that it matches to dst_ip, otherwise
+ dst_ip/dst_hw do not matter.
+ */
+ if (src_ip.s_addr != dst.s_addr)
+ return 0;
+ if (memcmp(p, &me.sll_addr, me.sll_halen) == 0)
+ return 0;
+ if (src.s_addr && src.s_addr != dst_ip.s_addr)
+ return 0;
+ }
+ if (!quiet) {
+ int s_printed = 0;
+
+ printf("%s ",
+ FROM->sll_pkttype == PACKET_HOST ? "Unicast" : "Broadcast");
+ printf("%s from ",
+ ah->ar_op == htons(ARPOP_REPLY) ? "reply" : "request");
+ printf("%s ", inet_ntoa(src_ip));
+ printf("[%s]", ether_ntoa((struct ether_addr *) p));
+ if (dst_ip.s_addr != src.s_addr) {
+ printf("for %s ", inet_ntoa(dst_ip));
+ s_printed = 1;
+ }
+ if (memcmp(p + ah->ar_hln + 4, me.sll_addr, ah->ar_hln)) {
+ if (!s_printed)
+ printf("for ");
+ printf("[%s]",
+ ether_ntoa((struct ether_addr *) p + ah->ar_hln + 4));
+ }
+ if (last.tv_sec) {
+ long usecs = (tv.tv_sec - last.tv_sec) * 1000000 +
+ tv.tv_usec - last.tv_usec;
+ long msecs = (usecs + 500) / 1000;
+
+ usecs -= msecs * 1000 - 500;
+ printf(" %ld.%03ldms\n", msecs, usecs);
+ } else {
+ printf(" UNSOLICITED?\n");
+ }
+ fflush(stdout);
+ }
+ received++;
+ if (FROM->sll_pkttype != PACKET_HOST)
+ brd_recv++;
+ if (ah->ar_op == htons(ARPOP_REQUEST))
+ req_recv++;
+ if (quit_on_reply)
+ finish();
+ if (!broadcast_only) {
+ memcpy(he.sll_addr, p, me.sll_halen);
+ unicasting = 1;
+ }
+ return 1;
+}
+
+int arping_main(int argc, char **argv)
+{
+ int socket_errno;
+ int ch;
+ uid_t uid = getuid();
+ char *device = "eth0";
+ int ifindex = 0;
+ char *source = NULL;
+ char *target;
+
+ s = socket(PF_PACKET, SOCK_DGRAM, 0);
+ socket_errno = errno;
+
+ setuid(uid);
+
+ while ((ch = getopt(argc, argv, "h?bfDUAqc:w:s:I")) != EOF) {
+ switch (ch) {
+ case 'b':
+ broadcast_only = 1;
+ break;
+ case 'D':
+ dad++;
+ quit_on_reply = 1;
+ break;
+ case 'U':
+ unsolicited++;
+ break;
+ case 'A':
+ advert++;
+ unsolicited++;
+ break;
+ case 'q':
+ quiet++;
+ break;
+ case 'c':
+ count = atoi(optarg);
+ break;
+ case 'w':
+ timeout = atoi(optarg);
+ break;
+ case 'I':
+ device = optarg;
+ break;
+ case 'f':
+ quit_on_reply = 1;
+ break;
+ case 's':
+ source = optarg;
+ break;
+ case 'h':
+ case '?':
+ default:
+ show_usage();
+ }
+ }
+ argc -= optind;
+ argv += optind;
+
+ if (argc != 1)
+ show_usage();
+
+ target = *argv;
+
+ if (device == NULL) {
+ error_msg("-I <interface> is required!");
+ exit(1);
+ }
+
+ if (s < 0) {
+ error_msg("socket");
+ exit(socket_errno);
+ }
+
+ if (1) {
+ struct ifreq ifr;
+
+ memset(&ifr, 0, sizeof(ifr));
+ strncpy(ifr.ifr_name, device, IFNAMSIZ - 1);
+ if (ioctl(s, SIOCGIFINDEX, &ifr) < 0) {
+ error_msg("unknown interface %s", device);
+ exit(2);
+ }
+ ifindex = ifr.ifr_ifindex;
+
+ if (ioctl(s, SIOCGIFFLAGS, (char *) &ifr)) {
+ error_msg("SIOCGIFFLAGS");
+ exit(2);
+ }
+ if (!(ifr.ifr_flags & IFF_UP)) {
+ error_msg("Interface \"%s\" is down", device);
+ exit(2);
+ }
+ if (ifr.ifr_flags & (IFF_NOARP | IFF_LOOPBACK)) {
+ error_msg("Interface \"%s\" is not ARPable", device);
+ exit(dad ? 0 : 2);
+ }
+ }
+
+ if (inet_aton(target, &dst) != 1) {
+ struct hostent *hp;
+
+ hp = gethostbyname2(target, AF_INET);
+ if (!hp) {
+ error_msg("invalid or unknown target %s", target);
+ exit(2);
+ }
+ memcpy(&dst, hp->h_addr, 4);
+ }
+
+ if (source && inet_aton(source, &src) != 1) {
+ error_msg("invalid source address %s", source);
+ exit(2);
+ }
+
+ if (!dad && unsolicited && src.s_addr == 0)
+ src = dst;
+
+ if (!dad || src.s_addr) {
+ struct sockaddr_in saddr;
+ int probe_fd = socket(AF_INET, SOCK_DGRAM, 0);
+
+ if (probe_fd < 0) {
+ error_msg("socket");
+ exit(2);
+ }
+ if (device) {
+ if (setsockopt
+ (probe_fd, SOL_SOCKET, SO_BINDTODEVICE, device,
+ strlen(device) + 1) == -1)
+ perror("WARNING: interface is ignored");
+ }
+ memset(&saddr, 0, sizeof(saddr));
+ saddr.sin_family = AF_INET;
+ if (src.s_addr) {
+ saddr.sin_addr = src;
+ if (bind(probe_fd, (struct sockaddr *) &saddr, sizeof(saddr)) == -1) {
+ error_msg("bind");
+ exit(2);
+ }
+ } else if (!dad) {
+ int on = 1;
+ int alen = sizeof(saddr);
+
+ saddr.sin_port = htons(1025);
+ saddr.sin_addr = dst;
+
+ if (setsockopt
+ (probe_fd, SOL_SOCKET, SO_DONTROUTE, (char *) &on,
+ sizeof(on)) == -1)
+ perror("WARNING: setsockopt(SO_DONTROUTE)");
+ if (connect(probe_fd, (struct sockaddr *) &saddr, sizeof(saddr))
+ == -1) {
+ error_msg("connect");
+ exit(2);
+ }
+ if (getsockname(probe_fd, (struct sockaddr *) &saddr, &alen) ==
+ -1) {
+ error_msg("getsockname");
+ exit(2);
+ }
+ src = saddr.sin_addr;
+ }
+ close(probe_fd);
+ };
+
+ me.sll_family = AF_PACKET;
+ me.sll_ifindex = ifindex;
+ me.sll_protocol = htons(ETH_P_ARP);
+ if (bind(s, (struct sockaddr *) &me, sizeof(me)) == -1) {
+ error_msg("bind");
+ exit(2);
+ }
+
+ if (1) {
+ int alen = sizeof(me);
+
+ if (getsockname(s, (struct sockaddr *) &me, &alen) == -1) {
+ error_msg("getsockname");
+ exit(2);
+ }
+ }
+ if (me.sll_halen == 0) {
+ error_msg("Interface \"%s\" is not ARPable (no ll address)", device);
+ exit(dad ? 0 : 2);
+ }
+ he = me;
+ memset(he.sll_addr, -1, he.sll_halen);
+
+ if (!quiet)
+ printf("ARPING to %s from %s via %s\n", inet_ntoa(dst),
+ inet_ntoa(src), device ? device : "unknown");
+
+ if (!src.s_addr && !dad) {
+ error_msg("no src address in the non-DAD mode");
+ exit(2);
+ }
+
+ {
+ struct sigaction sa;
+ memset(&sa, 0, sizeof(sa));
+ sa.sa_flags = SA_RESTART;
+
+ sa.sa_handler = (void (*)(int)) finish;
+ sigaction(SIGINT, &sa, NULL);
+
+ sa.sa_handler = (void (*)(int)) catcher;
+ sigaction(SIGALRM, &sa, NULL);
+ }
+
+ catcher();
+
+ while (1) {
+ sigset_t sset, osset;
+ char packet[4096];
+ struct sockaddr_ll from;
+ int alen = sizeof(from);
+ int cc;
+
+ if ((cc = recvfrom(s, packet, sizeof(packet), 0,
+ (struct sockaddr *) &from, &alen)) < 0) {
+ perror("recvfrom");
+ continue;
+ }
+ sigemptyset(&sset);
+ sigaddset(&sset, SIGALRM);
+ sigaddset(&sset, SIGINT);
+ sigprocmask(SIG_BLOCK, &sset, &osset);
+ recv_pack(packet, cc, &from);
+ sigprocmask(SIG_SETMASK, &osset, NULL);
+ }
+}
projects / oweals / busybox.git / commitdiff