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-rw-r--r--release/src/router/busybox/networking/arping.c545
1 files changed, 228 insertions, 317 deletions
diff --git a/release/src/router/busybox/networking/arping.c b/release/src/router/busybox/networking/arping.c
index 2e1adf0a..915af326 100644
--- a/release/src/router/busybox/networking/arping.c
+++ b/release/src/router/busybox/networking/arping.c
@@ -1,199 +1,199 @@
+/* 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 <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)
+#include "libbb.h"
+
+/* We don't expect to see 1000+ seconds delay, unsigned is enough */
+#define MONOTONIC_US() ((unsigned)monotonic_us())
+
+enum {
+ DAD = 1,
+ UNSOLICITED = 2,
+ ADVERT = 4,
+ QUIET = 8,
+ QUIT_ON_REPLY = 16,
+ BCAST_ONLY = 32,
+ UNICASTING = 64
+};
+
+struct globals {
+ struct in_addr src;
+ struct in_addr dst;
+ struct sockaddr_ll me;
+ struct sockaddr_ll he;
+ int sock_fd;
+
+ int count; // = -1;
+ unsigned last;
+ unsigned timeout_us;
+ unsigned start;
+
+ unsigned sent;
+ unsigned brd_sent;
+ unsigned received;
+ unsigned brd_recv;
+ unsigned req_recv;
+};
+#define G (*(struct globals*)&bb_common_bufsiz1)
+#define src (G.src )
+#define dst (G.dst )
+#define me (G.me )
+#define he (G.he )
+#define sock_fd (G.sock_fd )
+#define count (G.count )
+#define last (G.last )
+#define timeout_us (G.timeout_us)
+#define start (G.start )
+#define sent (G.sent )
+#define brd_sent (G.brd_sent )
+#define received (G.received )
+#define brd_recv (G.brd_recv )
+#define req_recv (G.req_recv )
+#define INIT_G() do { \
+ count = -1; \
+} while (0)
+
+// If GNUisms are not available...
+//static void *mempcpy(void *_dst, const void *_src, int n)
+//{
+// memcpy(_dst, _src, n);
+// return (char*)_dst + n;
+//}
+
+static int send_pack(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;
+ ah->ar_op = option_mask32 & ADVERT ? htons(ARPOP_REPLY) : htons(ARPOP_REQUEST);
- memcpy(p, src_addr, 4);
- p += 4;
+ p = mempcpy(p, &ME->sll_addr, ah->ar_hln);
+ p = mempcpy(p, src_addr, 4);
- if (advert)
- memcpy(p, &ME->sll_addr, ah->ar_hln);
+ if (option_mask32 & ADVERT)
+ p = mempcpy(p, &ME->sll_addr, ah->ar_hln);
else
- memcpy(p, &HE->sll_addr, ah->ar_hln);
- p += ah->ar_hln;
+ p = mempcpy(p, &HE->sll_addr, ah->ar_hln);
- memcpy(p, dst_addr, 4);
- p += 4;
+ p = mempcpy(p, dst_addr, 4);
- gettimeofday(&now, NULL);
- err = sendto(sock, buf, p - buf, 0, (struct sockaddr *) HE, sizeof(*HE));
+ err = sendto(sock_fd, buf, p - buf, 0, (struct sockaddr *) HE, sizeof(*HE));
if (err == p - buf) {
- last = now;
+ last = MONOTONIC_US();
sent++;
- if (!unicasting)
+ if (!(option_mask32 & UNICASTING))
brd_sent++;
}
return err;
}
-void finish(void)
+static void finish(void) NORETURN;
+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 (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 (!(option_mask32 & QUIET)) {
+ printf("Sent %u probe(s) (%u broadcast(s))\n"
+ "Received %u repl%s"
+ " (%u request(s), %u broadcast(s))\n",
+ sent, brd_sent,
+ received, (received == 1) ? "ies" : "y",
+ req_recv, brd_recv);
}
- if (dad)
+ if (option_mask32 & DAD)
exit(!!received);
- if (unsolicited)
- exit(0);
+ if (option_mask32 & UNSOLICITED)
+ exit(EXIT_SUCCESS);
exit(!received);
}
-void catcher(void)
+static void catcher(void)
{
- struct timeval tv;
- struct timeval start;
-
- gettimeofday(&tv, NULL);
+ unsigned now;
- if (start.tv_sec == 0)
- start = tv;
+ now = MONOTONIC_US();
+ if (start == 0)
+ start = now;
- if (count-- == 0
- || (timeout && MS_TDIFF(tv, start) > timeout * 1000 + 500))
+ if (count == 0 || (timeout_us && (now - start) > timeout_us))
finish();
- if (last.tv_sec == 0 || MS_TDIFF(tv, last) > 500) {
- send_pack(s, &src, &dst, &me, &he);
- if (count == 0 && unsolicited)
+ /* count < 0 means "infinite count" */
+ if (count > 0)
+ count--;
+
+ if (last == 0 || (now - last) > 500000) {
+ send_pack(&src, &dst, &me, &he);
+ if (count == 0 && (option_mask32 & UNSOLICITED))
finish();
}
alarm(1);
}
-int recv_pack(unsigned char *buf, int len, struct sockaddr_ll *FROM)
+static bool 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);
+ /* moves below assume in_addr is 4 bytes big, ensure that */
+ struct BUG_in_addr_must_be_4 {
+ char BUG_in_addr_must_be_4[
+ sizeof(struct in_addr) == 4 ? 1 : -1
+ ];
+ char BUG_s_addr_must_be_4[
+ sizeof(src_ip.s_addr) == 4 ? 1 : -1
+ ];
+ };
/* Filter out wild packets */
- if (FROM->sll_pkttype != PACKET_HOST &&
- FROM->sll_pkttype != PACKET_BROADCAST &&
- FROM->sll_pkttype != PACKET_MULTICAST)
- return 0;
+ if (FROM->sll_pkttype != PACKET_HOST
+ && FROM->sll_pkttype != PACKET_BROADCAST
+ && FROM->sll_pkttype != PACKET_MULTICAST)
+ return false;
/* Only these types are recognised */
if (ah->ar_op != htons(ARPOP_REQUEST) && ah->ar_op != htons(ARPOP_REPLY))
- return 0;
+ return false;
/* 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;
+ if (ah->ar_hrd != htons(FROM->sll_hatype)
+ && (FROM->sll_hatype != ARPHRD_FDDI || ah->ar_hrd != htons(ARPHRD_ETHER)))
+ return false;
/* 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;
+ if (ah->ar_pro != htons(ETH_P_IP)
+ || (ah->ar_pln != 4)
+ || (ah->ar_hln != me.sll_halen)
+ || (len < (int)(sizeof(*ah) + 2 * (4 + ah->ar_hln))))
+ return false;
+
+ move_from_unaligned32(src_ip.s_addr, p + ah->ar_hln);
+ move_from_unaligned32(dst_ip.s_addr, p + ah->ar_hln + 4 + ah->ar_hln);
+
+ if (dst.s_addr != src_ip.s_addr)
+ return false;
+ if (!(option_mask32 & DAD)) {
+ if ((src.s_addr != dst_ip.s_addr)
+ || (memcmp(p + ah->ar_hln + 4, &me.sll_addr, ah->ar_hln)))
+ return false;
} else {
/* DAD packet was:
src_ip = 0 (or some src)
@@ -208,22 +208,18 @@ int recv_pack(unsigned char *buf, int len, struct sockaddr_ll *FROM)
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 ((memcmp(p, &me.sll_addr, me.sll_halen) == 0)
+ || (src.s_addr && src.s_addr != dst_ip.s_addr))
+ return false;
}
- if (!quiet) {
+ if (!(option_mask32 & 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));
+ printf("%scast re%s from %s [%s]",
+ FROM->sll_pkttype == PACKET_HOST ? "Uni" : "Broad",
+ ah->ar_op == htons(ARPOP_REPLY) ? "ply" : "quest",
+ 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;
@@ -232,15 +228,12 @@ int recv_pack(unsigned char *buf, int len, struct sockaddr_ll *FROM)
if (!s_printed)
printf("for ");
printf("[%s]",
- ether_ntoa((struct ether_addr *) p + ah->ar_hln + 4));
+ 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);
+ if (last) {
+ unsigned diff = MONOTONIC_US() - last;
+ printf(" %u.%03ums\n", diff / 1000, diff % 1000);
} else {
printf(" UNSOLICITED?\n");
}
@@ -251,242 +244,160 @@ int recv_pack(unsigned char *buf, int len, struct sockaddr_ll *FROM)
brd_recv++;
if (ah->ar_op == htons(ARPOP_REQUEST))
req_recv++;
- if (quit_on_reply)
+ if (option_mask32 & QUIT_ON_REPLY)
finish();
- if (!broadcast_only) {
+ if (!(option_mask32 & BCAST_ONLY)) {
memcpy(he.sll_addr, p, me.sll_halen);
- unicasting = 1;
+ option_mask32 |= UNICASTING;
}
- return 1;
+ return true;
}
-int arping_main(int argc, char **argv)
+int arping_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int arping_main(int argc UNUSED_PARAM, char **argv)
{
- int socket_errno;
- int ch;
- uid_t uid = getuid();
- char *device = "eth0";
- int ifindex = 0;
+ const char *device = "eth0";
char *source = NULL;
char *target;
+ unsigned char *packet;
+ char *err_str;
- 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)
- bb_show_usage();
- if (bb_strlen(optarg) > IF_NAMESIZE) {
- bb_error_msg("Interface name `%s' must be less than %d", optarg,
- IF_NAMESIZE);
- exit(2);
- }
- device = optarg;
- break;
- case 'f':
- quit_on_reply = 1;
- break;
- case 's':
- source = optarg;
- break;
- case 'h':
- case '?':
- default:
- bb_show_usage();
- }
- }
- argc -= optind;
- argv += optind;
+ INIT_G();
- if (argc != 1)
- bb_show_usage();
+ sock_fd = xsocket(AF_PACKET, SOCK_DGRAM, 0);
- target = *argv;
+ // Drop suid root privileges
+ // Need to remove SUID_NEVER from applets.h for this to work
+ //xsetuid(getuid());
+ err_str = xasprintf("interface %s %%s", device);
+ {
+ unsigned opt;
+ char *str_timeout;
- if (s < 0) {
- bb_error_msg("socket");
- exit(socket_errno);
+ /* Dad also sets quit_on_reply.
+ * Advert also sets unsolicited.
+ */
+ opt_complementary = "=1:Df:AU:c+";
+ opt = getopt32(argv, "DUAqfbc:w:I:s:",
+ &count, &str_timeout, &device, &source);
+ if (opt & 0x80) /* -w: timeout */
+ timeout_us = xatou_range(str_timeout, 0, INT_MAX/2000000) * 1000000 + 500000;
+ //if (opt & 0x200) /* -s: source */
+ option_mask32 &= 0x3f; /* set respective flags */
}
+ target = argv[optind];
+
+ 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) {
- bb_error_msg("Interface %s not found", device);
- exit(2);
- }
- ifindex = ifr.ifr_ifindex;
+ strncpy_IFNAMSIZ(ifr.ifr_name, device);
+ /* We use ifr.ifr_name in error msg so that problem
+ * with truncated name will be visible */
+ ioctl_or_perror_and_die(sock_fd, SIOCGIFINDEX, &ifr, err_str, "not found");
+ me.sll_ifindex = ifr.ifr_ifindex;
+
+ xioctl(sock_fd, SIOCGIFFLAGS, (char *) &ifr);
- if (ioctl(s, SIOCGIFFLAGS, (char *) &ifr)) {
- bb_error_msg("SIOCGIFFLAGS");
- exit(2);
- }
if (!(ifr.ifr_flags & IFF_UP)) {
- bb_error_msg("Interface %s is down", device);
- exit(2);
+ bb_error_msg_and_die(err_str, "is down");
}
if (ifr.ifr_flags & (IFF_NOARP | IFF_LOOPBACK)) {
- bb_error_msg("Interface %s is not ARPable", device);
- exit(dad ? 0 : 2);
+ bb_error_msg(err_str, "is not ARPable");
+ return (option_mask32 & DAD ? 0 : 2);
}
}
- if (!inet_aton(target, &dst)) {
- struct hostent *hp;
-
- hp = gethostbyname2(target, AF_INET);
- if (!hp) {
- bb_error_msg("invalid or unknown target %s", target);
- exit(2);
- }
- memcpy(&dst, hp->h_addr, 4);
+ /* if (!inet_aton(target, &dst)) - not needed */ {
+ len_and_sockaddr *lsa;
+ lsa = xhost_and_af2sockaddr(target, 0, AF_INET);
+ dst = lsa->u.sin.sin_addr;
+ if (ENABLE_FEATURE_CLEAN_UP)
+ free(lsa);
}
if (source && !inet_aton(source, &src)) {
- bb_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 ((option_mask32 & (DAD|UNSOLICITED)) == UNSOLICITED && src.s_addr == 0)
src = dst;
- if (!dad || src.s_addr) {
+ if (!(option_mask32 & 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) {
- bb_error_msg("socket");
- exit(2);
- }
- if (device) {
- if (setsockopt
- (probe_fd, SOL_SOCKET, SO_BINDTODEVICE, device,
- strlen(device) + 1) == -1)
- bb_error_msg("WARNING: interface %s is ignored", device);
- }
+ setsockopt_bindtodevice(probe_fd, device);
memset(&saddr, 0, sizeof(saddr));
saddr.sin_family = AF_INET;
if (src.s_addr) {
+ /* Check that this is indeed our IP */
saddr.sin_addr = src;
- if (bind(probe_fd, (struct sockaddr *) &saddr, sizeof(saddr)) == -1) {
- bb_error_msg("bind");
- exit(2);
- }
- } else if (!dad) {
- int on = 1;
- int alen = sizeof(saddr);
+ xbind(probe_fd, (struct sockaddr *) &saddr, sizeof(saddr));
+ } else { /* !(option_mask32 & DAD) case */
+ /* Find IP address on this iface */
+ 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)");
- if (connect(probe_fd, (struct sockaddr *) &saddr, sizeof(saddr))
- == -1) {
- bb_error_msg("connect");
- exit(2);
- }
- if (getsockname(probe_fd, (struct sockaddr *) &saddr, &alen) ==
- -1) {
- bb_error_msg("getsockname");
- exit(2);
+ if (setsockopt(probe_fd, SOL_SOCKET, SO_DONTROUTE, &const_int_1, sizeof(const_int_1)) == -1)
+ bb_perror_msg("setsockopt(SO_DONTROUTE)");
+ xconnect(probe_fd, (struct sockaddr *) &saddr, sizeof(saddr));
+ if (getsockname(probe_fd, (struct sockaddr *) &saddr, &alen) == -1) {
+ bb_perror_msg_and_die("getsockname");
}
+ if (saddr.sin_family != AF_INET)
+ bb_error_msg_and_die("no IP address configured");
src = saddr.sin_addr;
}
close(probe_fd);
- };
+ }
me.sll_family = AF_PACKET;
- me.sll_ifindex = ifindex;
+ //me.sll_ifindex = ifindex; - done before
me.sll_protocol = htons(ETH_P_ARP);
- if (bind(s, (struct sockaddr *) &me, sizeof(me)) == -1) {
- bb_error_msg("bind");
- exit(2);
- }
+ xbind(sock_fd, (struct sockaddr *) &me, sizeof(me));
{
- int alen = sizeof(me);
+ socklen_t alen = sizeof(me);
- if (getsockname(s, (struct sockaddr *) &me, &alen) == -1) {
- bb_error_msg("getsockname");
- exit(2);
+ if (getsockname(sock_fd, (struct sockaddr *) &me, &alen) == -1) {
+ bb_perror_msg_and_die("getsockname");
}
}
if (me.sll_halen == 0) {
- bb_error_msg("Interface \"%s\" is not ARPable (no ll address)", device);
- exit(dad ? 0 : 2);
+ bb_error_msg(err_str, "is not ARPable (no ll address)");
+ return (option_mask32 & DAD ? 0 : 2);
}
he = me;
memset(he.sll_addr, -1, he.sll_halen);
- if (!quiet) {
+ if (!(option_mask32 & QUIET)) {
+ /* inet_ntoa uses static storage, can't use in same printf */
printf("ARPING to %s", inet_ntoa(dst));
- printf(" from %s via %s\n", inet_ntoa(src),
- device ? device : "unknown");
+ printf(" from %s via %s\n", inet_ntoa(src), device);
}
- if (!src.s_addr && !dad) {
- bb_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);
- }
+ signal_SA_RESTART_empty_mask(SIGINT, (void (*)(int))finish);
+ signal_SA_RESTART_empty_mask(SIGALRM, (void (*)(int))catcher);
catcher();
+ packet = xmalloc(4096);
while (1) {
sigset_t sset, osset;
- char 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,
- (struct sockaddr *) &from, &alen)) < 0) {
- perror("recvfrom");
+ cc = recvfrom(sock_fd, packet, 4096, 0, (struct sockaddr *) &from, &alen);
+ if (cc < 0) {
+ bb_perror_msg("recvfrom");
continue;
}
sigemptyset(&sset);