Changeset 2725 in MondoRescue for branches/2.2.9/mindi-busybox/networking/arping.c

Timestamp:

Feb 25, 2011, 9:26:54 PM (13 years ago)

Author:

Bruno Cornec

Message:

• Update mindi-busybox to 1.18.3 to avoid problems with the tar command which is now failing on recent versions with busybox 1.7.3

File:

• branches/2.2.9/mindi-busybox/networking/arping.c (modified) (21 diffs)

branches/2.2.9/mindi-busybox/networking/arping.c

@@ -1 +1 @@
 /* vi: set sw=4 ts=4: */
 /*
- * arping.c - Ping hosts by ARP requests/replies
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  *
- * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
- *
- * Author:  Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
+ * Author: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
  * Busybox port: Nick Fedchik <nick@fedchik.org.ua>
  */
@@ -18 +16 @@
 /* We don't expect to see 1000+ seconds delay, unsigned is enough */
 #define MONOTONIC_US() ((unsigned)monotonic_us())
-
-static struct in_addr src;
-static struct in_addr dst;
-static struct sockaddr_ll me;
-static struct sockaddr_ll he;
-static unsigned last;
 
 enum {
@@ -35 +27 @@
 };
 
-static int sock;
-static unsigned count = UINT_MAX;
-static unsigned timeout_us;
-static unsigned sent;
-static unsigned brd_sent;
-static unsigned received;
-static unsigned brd_recv;
-static unsigned req_recv;
+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;
+} FIX_ALIASING;
+#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,
@@ -49 +76 @@
 {
     int err;
-    unsigned 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);
@@ -61 +86 @@
     ah->ar_op = option_mask32 & 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;
+    p = mempcpy(p, &ME->sll_addr, ah->ar_hln);
+    p = mempcpy(p, src_addr, 4);
 
     if (option_mask32 & ADVERT)
-        memcpy(p, &ME->sll_addr, ah->ar_hln);
+        p = mempcpy(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;
-
-    now = MONOTONIC_US();
-    err = sendto(sock, buf, p - buf, 0, (struct sockaddr *) HE, sizeof(*HE));
+        p = mempcpy(p, &HE->sll_addr, ah->ar_hln);
+
+    p = mempcpy(p, dst_addr, 4);
+
+    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))
@@ -87 +106 @@
 }
 
-static void finish(void) ATTRIBUTE_NORETURN;
+static void finish(void) NORETURN;
 static void finish(void)
 {
@@ -101 +120 @@
         exit(!!received);
     if (option_mask32 & UNSOLICITED)
-        exit(0);
+        exit(EXIT_SUCCESS);
     exit(!received);
 }
@@ -107 +126 @@
 static void catcher(void)
 {
-    static unsigned start;
-
     unsigned now;
 
@@ -115 +132 @@
         start = now;
 
-    if (count == 0 || (timeout_us && (now - start) > (timeout_us + 500000)))
+    if (count == 0 || (timeout_us && (now - start) > timeout_us))
         finish();
 
-    count--;
+    /* count < 0 means "infinite count" */
+    if (count > 0)
+        count--;
 
     if (last == 0 || (now - last) > 500000) {
@@ -128 +147 @@
 }
 
-static 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 arphdr *ah = (struct arphdr *) buf;
     unsigned char *p = (unsigned char *) (ah + 1);
     struct in_addr src_ip, dst_ip;
+    /* 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 */
@@ -138 +166 @@
      && FROM->sll_pkttype != PACKET_BROADCAST
      && FROM->sll_pkttype != PACKET_MULTICAST)
-        return 0;
-
-    /* Only these types are recognised */
+        return false;
+
+    /* Only these types are recognized */
     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;
+        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 (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_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 ((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:
@@ -181 +207 @@
            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 (!(option_mask32 & QUIET)) {
@@ -208 +231 @@
 
         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");
         }
-        fflush(stdout);
+        fflush_all();
     }
     received++;
@@ -225 +249 @@
         option_mask32 |= UNICASTING;
     }
-    return 1;
+    return true;
 }
 
-int arping_main(int argc, char **argv);
-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)
 {
     const char *device = "eth0";
-    int ifindex;
     char *source = NULL;
     char *target;
     unsigned char *packet;
-
-    sock = xsocket(PF_PACKET, SOCK_DGRAM, 0);
+    char *err_str;
+
+    INIT_G();
+
+    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());
+
+    err_str = xasprintf("interface %s %%s", device);
     {
         unsigned opt;
-        char *str_count, *str_timeout;
+        char *str_timeout;
 
         /* Dad also sets quit_on_reply.
          * Advert also sets unsolicited.
          */
-        opt_complementary = "=1:Df:AU";
+        opt_complementary = "=1:Df:AU:c+";
         opt = getopt32(argv, "DUAqfbc:w:I:s:",
-                &str_count, &str_timeout, &device, &source);
-        if (opt & 0x40) /* -c: count */
-            count = xatou(str_count);
+                &count, &str_timeout, &device, &source);
         if (opt & 0x80) /* -w: timeout */
-            timeout_us = xatou_range(str_timeout, 0, INT_MAX/2000000) * 1000000;
-        //if (opt & 0x100) /* -I: interface */
-        if (strlen(device) >= IF_NAMESIZE) {
-            bb_error_msg_and_die("interface name '%s' is too long",
-                            device);
-        }
+            timeout_us = xatou_range(str_timeout, 0, INT_MAX/2000000) * 1000000 + 500000;
         //if (opt & 0x200) /* -s: source */
         option_mask32 &= 0x3f; /* set respective flags */
@@ -273 +294 @@
 
         memset(&ifr, 0, sizeof(ifr));
-        strncpy(ifr.ifr_name, device, IFNAMSIZ - 1);
-        ioctl_or_perror_and_die(sock, SIOCGIFINDEX, &ifr, "interface %s not found", device);
-        ifindex = ifr.ifr_ifindex;
-
-        xioctl(sock, SIOCGIFFLAGS, (char *) &ifr);
+        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 (!(ifr.ifr_flags & IFF_UP)) {
-            bb_error_msg_and_die("interface %s is down", device);
+            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);
+            bb_error_msg(err_str, "is not ARPable");
             return (option_mask32 & DAD ? 0 : 2);
         }
     }
 
-    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);
+        dst = lsa->u.sin.sin_addr;
         if (ENABLE_FEATURE_CLEAN_UP)
             free(lsa);
@@ -300 +323 @@
     }
 
-    if (!(option_mask32 & DAD) && (option_mask32 & UNSOLICITED) && src.s_addr == 0)
+    if ((option_mask32 & (DAD|UNSOLICITED)) == UNSOLICITED && src.s_addr == 0)
         src = dst;
 
@@ -307 +330 @@
         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_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;
             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);
 
@@ -323 +345 @@
 
             if (setsockopt(probe_fd, SOL_SOCKET, SO_DONTROUTE, &const_int_1, sizeof(const_int_1)) == -1)
-                bb_perror_msg("warning: setsockopt(SO_DONTROUTE)");
+                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");
-            }
+            getsockname(probe_fd, (struct sockaddr *) &saddr, &alen);
+            //never happens:
+            //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;
         }
@@ -334 +359 @@
 
     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");
-        }
+        getsockname(sock_fd, (struct sockaddr *) &me, &alen);
+        //never happens:
+        //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);
+        bb_error_msg(err_str, "is not ARPable (no ll address)");
         return (option_mask32 & DAD ? 0 : 2);
     }
@@ -353 +378 @@
 
     if (!(option_mask32 & QUIET)) {
-        printf("ARPING to %s from %s via %s\n",
-            inet_ntoa(dst), inet_ntoa(src),
-            device ? device : "unknown");
-    }
-
-    if (!src.s_addr && !(option_mask32 & DAD)) {
-        bb_error_msg_and_die("no src address in the non-DAD mode");
-    }
-
-    {
-        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);
-    }
+        /* 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);
+    }
+
+    signal_SA_RESTART_empty_mask(SIGINT,  (void (*)(int))finish);
+    signal_SA_RESTART_empty_mask(SIGALRM, (void (*)(int))catcher);
 
     catcher();
@@ -384 +395 @@
         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");