1 files changed, 33 insertions, 36 deletions

diff --git a/networking/arping.c b/networking/arping.c
index 771c3bccd..6383f9a88 100644
--- a/networking/arping.c
+++ b/networking/arping.c
@@ -33,7 +33,7 @@ struct globals {
         struct in_addr dst;
         struct sockaddr_ll me;
         struct sockaddr_ll he;
-        int sock;
+        int sock_fd;
 
         int count; // = -1;
         unsigned last;
@@ -51,7 +51,7 @@ struct globals {
 #define dst        (G.dst       )
 #define me         (G.me        )
 #define he         (G.he        )
-#define sock       (G.sock      )
+#define sock_fd    (G.sock_fd   )
 #define count      (G.count     )
 #define last       (G.last      )
 #define timeout_us (G.timeout_us)
@@ -71,7 +71,6 @@ static int send_pack(struct in_addr *src_addr,
                         struct sockaddr_ll *HE)
 {
         int err;
-        unsigned now;
         unsigned char buf[256];
         struct arphdr *ah = (struct arphdr *) buf;
         unsigned char *p = (unsigned char *) (ah + 1);
@@ -98,10 +97,9 @@ static int send_pack(struct in_addr *src_addr,
         memcpy(p, dst_addr, 4);
         p += 4;
 
-        now = MONOTONIC_US();
-        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 (!(option_mask32 & UNICASTING))
                         brd_sent++;
@@ -135,7 +133,7 @@ static void catcher(void)
         if (start == 0)
                 start = now;
 
-        if (count == 0 || (timeout_us && (now - start) > (timeout_us + 500000)))
+        if (count == 0 || (timeout_us && (now - start) > timeout_us))
                 finish();
 
         /* count < 0 means "infinite count" */
@@ -183,7 +181,7 @@ static int recv_pack(unsigned char *buf, int len, struct sockaddr_ll *FROM)
         memcpy(&src_ip, p + ah->ar_hln, 4);
         memcpy(&dst_ip, p + ah->ar_hln + 4 + ah->ar_hln, 4);
         if (!(option_mask32 & DAD)) {
-                if (src_ip.s_addr != dst.s_addr)
+                if (dst.s_addr != src_ip.s_addr)
                         return 0;
                 if (src.s_addr != dst_ip.s_addr)
                         return 0;
@@ -230,7 +228,8 @@ static int recv_pack(unsigned char *buf, int len, struct sockaddr_ll *FROM)
                 }
 
                 if (last) {
-                        printf(" %u.%03ums\n", last / 1000, last % 1000);
+                        unsigned diff = MONOTONIC_US() - last;
+                        printf(" %u.%03ums\n", diff / 1000, diff % 1000);
                 } else {
                         printf(" UNSOLICITED?\n");
                 }
@@ -254,17 +253,17 @@ int arping_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int arping_main(int argc, char **argv)
 {
         const char *device = "eth0";
-        int ifindex;
         char *source = NULL;
         char *target;
         unsigned char *packet;
 
         INIT_G();
 
-        sock = xsocket(PF_PACKET, SOCK_DGRAM, 0);
+        sock_fd = xsocket(AF_PACKET, SOCK_DGRAM, 0);
 
         // Drop suid root privileges
-        xsetuid(getuid());
+        // Need to remove SUID_NEVER from applets.h for this to work
+        //xsetuid(getuid());
 
         {
                 unsigned opt;
@@ -279,7 +278,7 @@ int arping_main(int argc, char **argv)
                 if (opt & 0x40) /* -c: count */
                         count = xatoi_u(str_count);
                 if (opt & 0x80) /* -w: timeout */
-                        timeout_us = xatou_range(str_timeout, 0, INT_MAX/2000000) * 1000000;
+                        timeout_us = xatou_range(str_timeout, 0, INT_MAX/2000000) * 1000000 + 500000;
                 //if (opt & 0x200) /* -s: source */
                 option_mask32 &= 0x3f; /* set respective flags */
         }
@@ -295,10 +294,10 @@ int arping_main(int argc, char **argv)
                 strncpy(ifr.ifr_name, device, sizeof(ifr.ifr_name) - 1);
                 /* We use ifr.ifr_name in error msg so that problem
                  * with truncated name will be visible */
-                ioctl_or_perror_and_die(sock, SIOCGIFINDEX, &ifr, "interface %s not found", ifr.ifr_name);
-                ifindex = ifr.ifr_ifindex;
+                ioctl_or_perror_and_die(sock_fd, SIOCGIFINDEX, &ifr, "interface %s not found", ifr.ifr_name);
+                me.sll_ifindex = ifr.ifr_ifindex;
 
-                xioctl(sock, SIOCGIFFLAGS, (char *) &ifr);
+                xioctl(sock_fd, SIOCGIFFLAGS, (char *) &ifr);
 
                 if (!(ifr.ifr_flags & IFF_UP)) {
                         bb_error_msg_and_die("interface %s is down", device);
@@ -309,7 +308,7 @@ int arping_main(int argc, char **argv)
                 }
         }
 
-        if (!inet_aton(target, &dst)) {
+        /* if (!inet_aton(target, &dst)) - not needed */ {
                 len_and_sockaddr *lsa;
                 lsa = xhost_and_af2sockaddr(target, 0, AF_INET);
                 memcpy(&dst, &lsa->sin.sin_addr.s_addr, 4);
@@ -321,23 +320,23 @@ int arping_main(int argc, char **argv)
                 bb_error_msg_and_die("invalid source address %s", source);
         }
 
-        if (!(option_mask32 & DAD) && (option_mask32 & UNSOLICITED) && src.s_addr == 0)
+        if ((option_mask32 & (DAD|UNSOLICITED)) == UNSOLICITED && src.s_addr == 0)
                 src = dst;
 
         if (!(option_mask32 & DAD) || src.s_addr) {
                 struct sockaddr_in saddr;
                 int probe_fd = xsocket(AF_INET, SOCK_DGRAM, 0);
 
-                if (device) {
-                        if (setsockopt(probe_fd, SOL_SOCKET, SO_BINDTODEVICE, device, strlen(device) + 1) == -1)
-                                bb_perror_msg("cannot bind to device %s", device);
-                }
+                if (setsockopt(probe_fd, SOL_SOCKET, SO_BINDTODEVICE, device, strlen(device) + 1) == -1)
+                        bb_perror_msg("cannot bind to device %s", 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;
                         xbind(probe_fd, (struct sockaddr *) &saddr, sizeof(saddr));
-                } else if (!(option_mask32 & DAD)) {
+                } else { /* !(option_mask32 & DAD) case */
+                        /* Find IP address on this iface */
                         socklen_t alen = sizeof(saddr);
 
                         saddr.sin_port = htons(1025);
@@ -347,23 +346,25 @@ int arping_main(int argc, char **argv)
                                 bb_perror_msg("setsockopt(SO_DONTROUTE)");
                         xconnect(probe_fd, (struct sockaddr *) &saddr, sizeof(saddr));
                         if (getsockname(probe_fd, (struct sockaddr *) &saddr, &alen) == -1) {
-                                bb_error_msg_and_die("getsockname");
+                                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);
-        xbind(sock, (struct sockaddr *) &me, sizeof(me));
+        xbind(sock_fd, (struct sockaddr *) &me, sizeof(me));
 
         {
                 socklen_t alen = sizeof(me);
 
-                if (getsockname(sock, (struct sockaddr *) &me, &alen) == -1) {
-                        bb_error_msg_and_die("getsockname");
+                if (getsockname(sock_fd, (struct sockaddr *) &me, &alen) == -1) {
+                        bb_perror_msg_and_die("getsockname");
                 }
         }
         if (me.sll_halen == 0) {
@@ -373,14 +374,10 @@ int arping_main(int argc, char **argv)
         he = me;
         memset(he.sll_addr, -1, he.sll_halen);
 
-        if (!src.s_addr && !(option_mask32 & DAD)) {
-                bb_error_msg_and_die("no src address in the non-DAD mode");
-        }
-
         if (!(option_mask32 & QUIET)) {
-                printf("ARPING to %s from %s via %s\n",
-                        inet_ntoa(dst), inet_ntoa(src),
-                        device ? device : "unknown");
+                /* 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);
         }
 
         {
@@ -405,7 +402,7 @@ int arping_main(int argc, char **argv)
                 socklen_t alen = sizeof(from);
                 int cc;
 
-                cc = recvfrom(sock, packet, 4096, 0, (struct sockaddr *) &from, &alen);
+                cc = recvfrom(sock_fd, packet, 4096, 0, (struct sockaddr *) &from, &alen);
                 if (cc < 0) {
                         bb_perror_msg("recvfrom");
                         continue;