traceroute: commonalize verbose printing

function                                             old     new   delta
hexdump                                                -     274    +274
traceroute_init                                     1172    1147     -25
pr_type                                               79       -     -79
common_traceroute_main                              2091    1785    -306
------------------------------------------------------------------------------
(add/remove: 1/1 grow/shrink: 0/2 up/down: 274/-410)         Total: -136 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 62 insertions, 83 deletions

diff --git a/networking/traceroute.c b/networking/traceroute.c
index cf2b3cc64..0fb01ff5b 100644
--- a/networking/traceroute.c
+++ b/networking/traceroute.c
@@ -358,7 +358,11 @@ enum {
         OPT_IPV4         = (1 << 17),   /* 4 */
         OPT_IPV6         = (1 << 18) * ENABLE_TRACEROUTE6, /* 6 */
 };
-#define verbose (option_mask32 & OPT_VERBOSE)
+#if ENABLE_FEATURE_TRACEROUTE_VERBOSE
+# define verbose (option_mask32 & OPT_VERBOSE)
+#else
+# define verbose 0
+#endif
 
 enum {
         SIZEOF_ICMP_HDR = 8,
@@ -559,9 +563,7 @@ send_probe(int seq, int ttl)
 }
 
 #if ENABLE_FEATURE_TRACEROUTE_VERBOSE
-/*
- * Convert an ICMP "type" field to a printable string.
- */
+/* Convert an ICMP "type" field to a printable string */
 static const char *
 pr_type(unsigned char t)
 {
@@ -594,12 +596,35 @@ pr_type(unsigned char t)
 
         return ttab[t];
 }
+static void
+hexdump(const struct icmp *icp, int len)
+{
+        const unsigned char *p;
+        int i;
+
+        printf("\n%d bytes from %s to %s: icmp type %d (%s) code %d\n",
+                len,
+                auto_string(xmalloc_sockaddr2dotted_noport(&G.from_lsa->u.sa)),
+                auto_string(xmalloc_sockaddr2dotted_noport(G.to)),
+                icp->icmp_type, pr_type(icp->icmp_type),
+                icp->icmp_code
+        );
+        p = (const void *)icp;
+        for (i = 0; i < len; i++) {
+                if (i % 16 == 0)
+                        printf("%04x:", i);
+                if (i % 4 == 0)
+                        bb_putchar(' ');
+                printf("%02x", p[i]);
+                if ((i % 16 == 15) && (i + 1 < len))
+                        bb_putchar('\n');
+        }
+        bb_putchar('\n');
+}
+#else
+# define hexdump(...) ((void)0)
 #endif
 
-#if !ENABLE_FEATURE_TRACEROUTE_VERBOSE
-#define packet4_ok(read_len, from, seq) \
-        packet4_ok(read_len, seq)
-#endif
 static int
 packet4_ok(int read_len, int seq)
 {
@@ -616,11 +641,9 @@ packet4_ok(int read_len, int seq)
 
         hlen = ip->ip_hl << 2;
         if (read_len < hlen + ICMP_MINLEN) {
-#if ENABLE_FEATURE_TRACEROUTE_VERBOSE
                 if (verbose)
                         printf("packet too short (%d bytes) from %s\n", read_len,
                                 inet_ntoa(G.from_lsa->u.sin.sin_addr));
-#endif
                 return 0;
         }
         read_len -= hlen;
@@ -677,24 +700,8 @@ packet4_ok(int read_len, int seq)
                         }
                 }
         }
-#if ENABLE_FEATURE_TRACEROUTE_VERBOSE
-        if (verbose) {
-                int i;
-                uint32_t *lp = (uint32_t *)&icp->icmp_ip;
-
-                printf("\n%d bytes from %s to %s: icmp type %d (%s) code %d\n",
-                        read_len,
-                        /* inet_ntoa(G.from_lsa->u.sin.sin_addr) - two calls of inet_ntoa()
-                         * are unsafe (use the same buffer), using this instead:
-                         */
-                        auto_string(xmalloc_sockaddr2dotted_noport(&G.from_lsa->u.sa)),
-                        inet_ntoa(ip->ip_dst),
-                        type, pr_type(type), icp->icmp_code
-                );
-                for (i = 4; i < read_len; i += sizeof(*lp))
-                        printf("%2d: x%8.8x\n", i, *lp++);
-        }
-#endif
+        if (verbose)
+                hexdump(icp, read_len);
         return 0;
 }
 
@@ -754,34 +761,9 @@ packet6_ok(int read_len, int seq)
                         }
                 }
         }
-
-# if ENABLE_FEATURE_TRACEROUTE_VERBOSE
-        if (verbose) {
-                unsigned char *p;
-                int i;
-
-                p = (unsigned char *) (icp + 1);
-
-                printf("\n%d bytes from %s to %s: icmp type %d (%s) code %d\n",
-                        read_len,
-                        auto_string(xmalloc_sockaddr2dotted_noport(&G.from_lsa->u.sa)),
-                        auto_string(xmalloc_sockaddr2dotted_noport(G.to)),
-                        type, pr_type(type), icp->icmp6_code
-                );
-                read_len -= sizeof(struct icmp6_hdr);
-                for (i = 0; i < read_len; i++) {
-                        if (i % 16 == 0)
-                                printf("%04x:", i);
-                        if (i % 4 == 0)
-                                bb_putchar(' ');
-                        printf("%02x", p[i]);
-                        if ((i % 16 == 15) && (i + 1 < read_len))
-                                bb_putchar('\n');
-                }
-                bb_putchar('\n');
-        }
-# endif
-
+        if (verbose)
+                /* cast is safe since the beginning of icmp4 and icmp6 layouts match */
+                hexdump((const struct icmp *)icp, read_len);
         return 0;
 }
 
@@ -910,7 +892,7 @@ traceroute_init(int op, char **argv)
                 packlen = sizeof(struct ip)
                         + SIZEOF_ICMP_HDR
                         + sizeof(struct outdata_t);
-                port = 0; /* on ICMP6 sockets, sendto(ipv6.nonzero_port) throws EINVAL */
+                port = 0; /* on ICMP6 sockets, sendto(ipv6.nonzero_port) throws EINVAL! */
         }
 #if ENABLE_TRACEROUTE6
         af = AF_UNSPEC;
@@ -932,23 +914,24 @@ traceroute_init(int op, char **argv)
 #else
         dest_lsa = xhost2sockaddr(argv[0], port);
 #endif
+//TODO: make sure af == AF_INET[6]? (FEATURE_UNIX_LOCAL=y allows "local:/PATH" to be translated to AF_UNIX)
         G.from_lsa = xmemdup(dest_lsa, LSA_LEN_SIZE + dest_lsa->len);
         G.to = xzalloc(dest_lsa->len);
         if (argv[1])
                 packlen = xatoul_range(argv[1], packlen, 32 * 1024);
 
+        if (af == AF_INET) {
+                xmove_fd(xsocket(AF_INET, SOCK_RAW, IPPROTO_ICMP), rcvsock);
+                /* want recvmsg to report target local address (for -v) */
+                setsockopt_1(rcvsock, IPPROTO_IP, IP_PKTINFO);
+        }
 #if ENABLE_TRACEROUTE6
-        if (af == AF_INET6) {
+        else {
                 xmove_fd(xsocket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6), rcvsock);
                 /* want recvmsg to report target local address (for -v) */
                 setsockopt_1(rcvsock, SOL_IPV6, IPV6_RECVPKTINFO);
-        } else
-#endif
-        {
-                xmove_fd(xsocket(AF_INET, SOCK_RAW, IPPROTO_ICMP), rcvsock);
-                /* want recvmsg to report target local address (for -v) */
-                setsockopt_1(rcvsock, IPPROTO_IP, IP_PKTINFO);
         }
+#endif
 
 #if TRACEROUTE_SO_DEBUG
         if (op & OPT_DEBUG)
@@ -959,22 +942,22 @@ traceroute_init(int op, char **argv)
 
         {
                 int snd;
+                if (af == AF_INET) {
+                        if (op & OPT_USE_ICMP)
+                                snd = xsocket(AF_INET, SOCK_RAW, IPPROTO_ICMP);
+                        else
+                                snd = xsocket(AF_INET, SOCK_DGRAM, 0);
+                }
 #if ENABLE_TRACEROUTE6
-                if (af == AF_INET6) {
+                else {
                         if (setsockopt_int(rcvsock, SOL_RAW, IPV6_CHECKSUM, 2) != 0)
                                 bb_perror_msg_and_die("setsockopt(%s)", "IPV6_CHECKSUM");
                         if (op & OPT_USE_ICMP)
                                 snd = xsocket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6);
                         else
                                 snd = xsocket(AF_INET6, SOCK_DGRAM, 0);
-                } else
-#endif
-                {
-                        if (op & OPT_USE_ICMP)
-                                snd = xsocket(AF_INET, SOCK_RAW, IPPROTO_ICMP);
-                        else
-                                snd = xsocket(AF_INET, SOCK_DGRAM, 0);
                 }
+#endif
                 xmove_fd(snd, sndsock);
         }
 
@@ -1006,7 +989,7 @@ traceroute_init(int op, char **argv)
         ident = getpid();
 
         outdata = (void*)(outudp + 1);
-        if (!ENABLE_TRACEROUTE6 || af == AF_INET) {
+        if (af == AF_INET) {
                 if (op & OPT_USE_ICMP) {
                         outicmp->icmp_type = ICMP_ECHO;
                         /*outicmp->icmp_code = 0; - set by xzalloc */
@@ -1015,7 +998,7 @@ traceroute_init(int op, char **argv)
                 }
         }
 #if ENABLE_TRACEROUTE6
-        if (af == AF_INET6) {
+        else {
                 outdata = (void*)(outudp6 + 1);
                 if (op & OPT_USE_ICMP) {
                         outicmp6->icmp_type = ICMP6_ECHO_REQUEST;
@@ -1048,26 +1031,22 @@ traceroute_init(int op, char **argv)
                 xbind(sndsock, &source_lsa->u.sa, source_lsa->len);
                 if (ENABLE_FEATURE_CLEAN_UP)
                         free(source_lsa);
-        }
-#if ENABLE_TRACEROUTE6
-        else if (af == AF_INET6) {
-//TODO: why we don't do it for IPv4?
+        } else {
                 len_and_sockaddr *source_lsa;
 
                 set_nport(&dest_lsa->u.sa, htons(port));
-                /* Connect makes kernel pick source IP and port */
+                /* Connect makes kernel pick source IP (and port if UDP) */
                 xconnect(sndsock, &dest_lsa->u.sa, dest_lsa->len);
                 /* Read IP and port */
                 source_lsa = get_sock_lsa(sndsock);
                 if (source_lsa == NULL)
-                        bb_simple_error_msg_and_die("can't get probe addr");
-                /* bind our recv socket to this IP (but not port) */
-                set_nport(&source_lsa->u.sa, 0);
+                        bb_simple_perror_msg_and_die("getsockname");
+                /* bind our recv ICMP socket to this IP (but not port, ICMP has no ports) */
+                //set_nport(&source_lsa->u.sa, 0); - paranoia, seems to work without this for both ipv4 and ipv6
                 xbind(rcvsock, &source_lsa->u.sa, source_lsa->len);
                 if (ENABLE_FEATURE_CLEAN_UP)
                         free(source_lsa);
         }
-#endif
 
         /* Revert to non-privileged user after opening sockets */
         xsetgid(getgid());