+/* vi: set sw=4 ts=4: */
/*
* 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.
+ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*
* 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 <signal.h>
#include <errno.h>
#include <stdlib.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;
+static struct in_addr src;
+static struct in_addr dst;
+static struct sockaddr_ll me;
+static struct sockaddr_ll he;
+static struct timeval last;
+
+enum cfg_e {
+ dad = 1,
+ unsolicited = 2,
+ advert = 4,
+ quiet = 8,
+ quit_on_reply = 16,
+ broadcast_only = 32,
+ unicasting = 64
+};
+static int cfg;
+
+static int s;
+static unsigned count = UINT_MAX;
+static unsigned timeout;
+static int sent;
+static int brd_sent;
+static int received;
+static int brd_recv;
+static 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];
+ RESERVE_CONFIG_UBUFFER(buf, 256);
struct arphdr *ah = (struct arphdr *) buf;
unsigned char *p = (unsigned char *) (ah + 1);
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);
+ ah->ar_op = cfg&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)
+ if (cfg&advert)
memcpy(p, &ME->sll_addr, ah->ar_hln);
else
memcpy(p, &HE->sll_addr, ah->ar_hln);
if (err == p - buf) {
last = now;
sent++;
- if (!unicasting)
+ if (!(cfg&unicasting))
brd_sent++;
}
+ RELEASE_CONFIG_BUFFER(buf);
return err;
}
-void finish(void)
+static 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 (!(cfg&quiet)) {
+ printf("Sent %d probes (%d broadcast(s))\n"
+ "Received %d repl%s",
+ sent, brd_sent,
+ received, (received > 1) ? "ies" : "y");
if (brd_recv || req_recv) {
printf(" (");
if (req_recv)
putchar('\n');
fflush(stdout);
}
- if (dad)
+ if (cfg&dad)
exit(!!received);
- if (unsolicited)
+ if (cfg&unsolicited)
exit(0);
exit(!received);
}
-void catcher(void)
+static void catcher(void)
{
struct timeval tv;
- struct timeval start;
+ static struct timeval start;
gettimeofday(&tv, NULL);
if (last.tv_sec == 0 || MS_TDIFF(tv, last) > 500) {
send_pack(s, &src, &dst, &me, &he);
- if (count == 0 && unsolicited)
+ if (count == 0 && cfg&unsolicited)
finish();
}
alarm(1);
}
-int recv_pack(unsigned char *buf, int len, struct sockaddr_ll *FROM)
+static 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 &&
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 (!(cfg&dad)) {
if (src_ip.s_addr != dst.s_addr)
return 0;
if (src.s_addr != dst_ip.s_addr)
if (src.s_addr && src.s_addr != dst_ip.s_addr)
return 0;
}
- if (!quiet) {
+ if (!(cfg&quiet)) {
int s_printed = 0;
+ struct timeval tv;
+
+ gettimeofday(&tv, NULL);
- 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));
+ printf("%s %s from %s [%s]",
+ FROM->sll_pkttype == PACKET_HOST ? "Unicast" : "Broadcast",
+ ah->ar_op == htons(ARPOP_REPLY) ? "reply" : "request",
+ inet_ntoa(src_ip),
+ ether_ntoa((struct ether_addr *) p));
if (dst_ip.s_addr != src.s_addr) {
printf("for %s ", inet_ntoa(dst_ip));
s_printed = 1;
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;
brd_recv++;
if (ah->ar_op == htons(ARPOP_REQUEST))
req_recv++;
- if (quit_on_reply)
+ if (cfg&quit_on_reply)
finish();
- if (!broadcast_only) {
+ if (!(cfg&broadcast_only)) {
memcpy(he.sll_addr, p, me.sll_halen);
- unicasting = 1;
+ cfg |= unicasting;
}
return 1;
}
int arping_main(int argc, char **argv)
{
- int socket_errno;
- int ch;
- uid_t uid = getuid();
char *device = "eth0";
- int ifindex = 0;
+ int ifindex;
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':
- if (optarg == NULL)
- show_usage();
- if (xstrlen(optarg) > IF_NAMESIZE) {
- error_msg("Interface name `%s' must be less than %d", optarg,
- IF_NAMESIZE);
- exit(2);
+ s = xsocket(PF_PACKET, SOCK_DGRAM, 0);
+
+ // Drop suid root privileges
+ xsetuid(getuid());
+
+ {
+ unsigned opt;
+ char *_count, *_timeout;
+
+ /* Dad also sets quit_on_reply.
+ * Advert also sets unsolicited.
+ */
+ opt_complementary = "Df:AU";
+ opt = getopt32(argc, argv, "DUAqfbc:w:i:s:",
+ &_count, &_timeout, &device, &source);
+ cfg |= opt & 0x3f; /* set respective flags */
+ if (opt & 0x40) /* -c: count */
+ count = xatou(_count);
+ if (opt & 0x80) /* -w: timeout */
+ timeout = xatoul_range(_timeout, 0, INT_MAX/2000);
+ if (opt & 0x100) { /* -i: interface */
+ if (strlen(device) > IF_NAMESIZE) {
+ bb_error_msg_and_die("interface name '%s' is too long",
+ device);
}
- device = optarg;
- break;
- case 'f':
- quit_on_reply = 1;
- break;
- case 's':
- source = optarg;
- break;
- case 'h':
- case '?':
- default:
- show_usage();
}
+ //if (opt & 0x200) /* -s: source */
}
argc -= optind;
argv += optind;
if (argc != 1)
- show_usage();
+ bb_show_usage();
target = *argv;
-
- if (s < 0) {
- error_msg("socket");
- exit(socket_errno);
- }
+ xfunc_error_retval = 2;
{
struct ifreq ifr;
memset(&ifr, 0, sizeof(ifr));
strncpy(ifr.ifr_name, device, IFNAMSIZ - 1);
if (ioctl(s, SIOCGIFINDEX, &ifr) < 0) {
- error_msg("Interface %s not found", device);
- exit(2);
+ bb_error_msg_and_die("interface %s not found", device);
}
ifindex = ifr.ifr_ifindex;
if (ioctl(s, SIOCGIFFLAGS, (char *) &ifr)) {
- error_msg("SIOCGIFFLAGS");
- exit(2);
+ bb_error_msg_and_die("SIOCGIFFLAGS");
}
if (!(ifr.ifr_flags & IFF_UP)) {
- error_msg("Interface %s is down", device);
- exit(2);
+ bb_error_msg_and_die("interface %s is down", device);
}
if (ifr.ifr_flags & (IFF_NOARP | IFF_LOOPBACK)) {
- error_msg("Interface %s is not ARPable", device);
- exit(dad ? 0 : 2);
+ bb_error_msg("interface %s is not ARPable", device);
+ exit(cfg&dad ? 0 : 2);
}
}
hp = gethostbyname2(target, AF_INET);
if (!hp) {
- error_msg("invalid or unknown target %s", target);
- exit(2);
+ bb_error_msg_and_die("invalid or unknown target %s", target);
}
memcpy(&dst, hp->h_addr, 4);
}
if (source && !inet_aton(source, &src)) {
- error_msg("invalid source address %s", source);
- exit(2);
+ bb_error_msg_and_die("invalid source address %s", source);
}
- if (!dad && unsolicited && src.s_addr == 0)
+ if (!(cfg&dad) && cfg&unsolicited && src.s_addr == 0)
src = dst;
- if (!dad || src.s_addr) {
+ if (!(cfg&dad) || src.s_addr) {
struct sockaddr_in saddr;
- int probe_fd = socket(AF_INET, SOCK_DGRAM, 0);
+ int probe_fd = xsocket(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)
- error_msg("WARNING: interface %s is ignored", device);
+ bb_error_msg("warning: interface %s is ignored", device);
}
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);
+ bb_error_msg_and_die("bind");
}
- } else if (!dad) {
+ } else if (!(cfg&dad)) {
int on = 1;
- int alen = sizeof(saddr);
+ socklen_t 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)");
+ bb_perror_msg("warning: setsockopt(SO_DONTROUTE)");
if (connect(probe_fd, (struct sockaddr *) &saddr, sizeof(saddr))
== -1) {
- error_msg("connect");
- exit(2);
+ bb_error_msg_and_die("connect");
}
if (getsockname(probe_fd, (struct sockaddr *) &saddr, &alen) ==
-1) {
- error_msg("getsockname");
- exit(2);
+ bb_error_msg_and_die("getsockname");
}
src = saddr.sin_addr;
}
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);
+ bb_error_msg_and_die("bind");
}
{
- int alen = sizeof(me);
+ socklen_t alen = sizeof(me);
if (getsockname(s, (struct sockaddr *) &me, &alen) == -1) {
- error_msg("getsockname");
- exit(2);
+ bb_error_msg_and_die("getsockname");
}
}
if (me.sll_halen == 0) {
- error_msg("Interface \"%s\" is not ARPable (no ll address)", device);
- exit(dad ? 0 : 2);
+ bb_error_msg("interface \"%s\" is not ARPable (no ll address)", device);
+ exit(cfg&dad ? 0 : 2);
}
he = me;
memset(he.sll_addr, -1, he.sll_halen);
- if (!quiet) {
- printf("ARPING to %s", inet_ntoa(dst));
- printf(" from %s via %s\n", inet_ntoa(src),
- device ? device : "unknown");
+ if (!(cfg&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);
+ if (!src.s_addr && !(cfg&dad)) {
+ bb_error_msg_and_die("no src address in the non-DAD mode");
}
{
while (1) {
sigset_t sset, osset;
- char packet[4096];
+ RESERVE_CONFIG_UBUFFER(packet, 4096);
struct sockaddr_ll from;
- int alen = sizeof(from);
+ socklen_t alen = sizeof(from);
int cc;
- if ((cc = recvfrom(s, packet, sizeof(packet), 0,
+ if ((cc = recvfrom(s, packet, 4096, 0,
(struct sockaddr *) &from, &alen)) < 0) {
- perror("recvfrom");
+ bb_perror_msg("recvfrom");
continue;
}
sigemptyset(&sset);
sigprocmask(SIG_BLOCK, &sset, &osset);
recv_pack(packet, cc, &from);
sigprocmask(SIG_SETMASK, &osset, NULL);
+ RELEASE_CONFIG_BUFFER(packet);
}
}