ping: support -I addr in family neutral manner; reuse a bit of common code

include/libbb.h

@@ -321,6 +321,7 @@ int xconnect_stream(const len_and_sockaddr *lsa);
 len_and_sockaddr* host2sockaddr(const char *host, int port);
 /* Version which dies on error */
 len_and_sockaddr* xhost2sockaddr(const char *host, int port);
+len_and_sockaddr* xdotted2sockaddr(const char *host, int port);
 #if ENABLE_FEATURE_IPV6
 /* Same, useful if you want to force family (e.g. IPv6) */
 len_and_sockaddr* host_and_af2sockaddr(const char *host, int port, sa_family_t af);

include/usage.h

@@ -2428,9 +2428,10 @@
 #define ping_full_usage \
        "Send ICMP ECHO_REQUEST packets to network hosts" \
        "\n\nOptions:\n" \
+       "	-4, -6		Force IPv4 or IPv6 hostname resolution\n" \
        "	-c CNT		Send only CNT pings\n" \
        "	-s SIZE		Send SIZE data bytes in packets (default=56)\n" \
-       "	-I IP	Use IP as source address\n" \
+       "	-I iface/IP	Use interface or IP address as source\n" \
        "	-q		Quiet mode, only displays output at start\n" \
        "			and when finished"
 #define ping6_trivial_usage \
@@ -2440,6 +2441,7 @@
        "\n\nOptions:\n" \
        "	-c CNT		Send only CNT pings\n" \
        "	-s SIZE		Send SIZE data bytes in packets (default=56)\n" \
+       "	-I iface/IP	Use interface or IP address as source\n" \
        "	-q		Quiet mode, only displays output at start\n" \
        "			and when finished"
 #endif

libbb/xconnect.c

@@ -203,7 +203,7 @@ len_and_sockaddr* xhost2sockaddr(const char *host, int port)
 	return str2sockaddr(host, port, AF_UNSPEC, DIE_ON_ERROR);
 }
 
-static len_and_sockaddr* xdotted2sockaddr(const char *host, int port)
+len_and_sockaddr* xdotted2sockaddr(const char *host, int port)
 {
 	return str2sockaddr(host, port, AF_UNSPEC, AI_NUMERICHOST | DIE_ON_ERROR);
 }

networking/ping.c

@@ -254,7 +254,7 @@ static union {
 	struct sockaddr_in6 sin6;
 #endif
 } pingaddr;
-static struct sockaddr_in sourceaddr;
+static len_and_sockaddr *source_lsa;
 static int pingsock = -1;
 static unsigned datalen; /* intentionally uninitialized to work around gcc bug */
 
@@ -561,9 +561,8 @@ static void ping4(len_and_sockaddr *lsa)
 
 	pingsock = create_icmp_socket();
 	pingaddr.sin = lsa->sin;
-	if (sourceaddr.sin_addr.s_addr) {
+	if (source_lsa)
-		xbind(pingsock, (struct sockaddr*)&sourceaddr, sizeof(sourceaddr));
+		xbind(pingsock, &lsa->sa, lsa->len);
-	}
 
 	/* enable broadcast pings */
 	setsockopt_broadcast(pingsock);
@@ -572,13 +571,6 @@ static void ping4(len_and_sockaddr *lsa)
 	sockopt = 48 * 1024; /* explain why 48k? */
 	setsockopt(pingsock, SOL_SOCKET, SO_RCVBUF, &sockopt, sizeof(sockopt));
 
-	printf("PING %s (%s)", hostname, dotted);
-	if (sourceaddr.sin_addr.s_addr) {
-		printf(" from %s",
-			inet_ntoa(*(struct in_addr *) &sourceaddr.sin_addr.s_addr));
-	}
-	printf(": %d data bytes\n", datalen);
-
 	signal(SIGINT, pingstats);
 
 	/* start the ping's going ... */
@@ -615,9 +607,9 @@ static void ping6(len_and_sockaddr *lsa)
 
 	pingsock = create_icmp6_socket();
 	pingaddr.sin6 = lsa->sin6;
-	//if (sourceaddr.sin_addr.s_addr) {
+	/* untested whether "-I addr" really works for IPv6: */
-	//	xbind(pingsock, (struct sockaddr*)&sourceaddr, sizeof(sourceaddr));
+	if (source_lsa)
-	//}
+		xbind(pingsock, &lsa->sa, lsa->len);
 
 #ifdef ICMP6_FILTER
 	{
@@ -652,8 +644,6 @@ static void ping6(len_and_sockaddr *lsa)
 	if (if_index)
 		pingaddr.sin6.sin6_scope_id = if_index;
 
-	printf("PING %s (%s): %d data bytes\n", hostname, dotted, datalen);
-
 	signal(SIGINT, pingstats);
 
 	/* start the ping's going ... */
@@ -695,25 +685,21 @@ static void ping6(len_and_sockaddr *lsa)
 }
 #endif
 
-/* TODO: consolidate ether-wake.c, dnsd.c, ifupdown.c, nslookup.c
+static void ping(len_and_sockaddr *lsa)
- * versions of below thing. BTW we have far too many "%u.%u.%u.%u" too...
-*/
-static int parse_nipquad(const char *str, struct sockaddr_in* addr)
 {
-	char dummy;
+	printf("PING %s (%s)", hostname, dotted);
-	unsigned i1, i2, i3, i4;
+	if (source_lsa) {
-	if (sscanf(str, "%u.%u.%u.%u%c",
+		printf(" from %s",
-			   &i1, &i2, &i3, &i4, &dummy) == 4
+			xmalloc_sockaddr2dotted_noport(&lsa->sa, lsa->len));
-	&& ( (i1|i2|i3|i4) <= 0xff )
-	) {
-		uint8_t* ptr = (uint8_t*)&addr->sin_addr;
-		ptr[0] = i1;
-		ptr[1] = i2;
-		ptr[2] = i3;
-		ptr[3] = i4;
-		return 0;
 	}
-	return 1; /* error */
+	printf(": %d data bytes\n", datalen);
+
+#if ENABLE_PING6
+	if (lsa->sa.sa_family == AF_INET6)
+		ping6(lsa);
+	else
+#endif
+		ping4(lsa);
 }
 
 int ping_main(int argc, char **argv);
@@ -732,9 +718,11 @@ int ping_main(int argc, char **argv)
 	if (option_mask32 & OPT_s) datalen = xatou16(opt_s); // -s
 	if (option_mask32 & OPT_I) { // -I
 		if_index = if_nametoindex(opt_I);
-		if (!if_index)
+		if (!if_index) {
-			if (parse_nipquad(opt_I, &sourceaddr))
+			/* TODO: I'm not sure it takes IPv6 unless in [XX:XX..] format */
-				bb_show_usage();
+			/* (ping doesn't support source IPv6 addresses yet anyway) */
+			source_lsa = xdotted2sockaddr(opt_I, 0);
+		}
 	}
 	myid = (int16_t) getpid();
 	hostname = argv[optind];
@@ -747,13 +735,13 @@ int ping_main(int argc, char **argv)
 #else
 	lsa = xhost_and_af2sockaddr(hostname, 0, AF_INET);
 #endif
+
+	if (source_lsa && source_lsa->sa.sa_family != lsa->sa.sa_family)
+		/* leaking it here... */
+		source_lsa = NULL;
+
 	dotted = xmalloc_sockaddr2dotted_noport(&lsa->sa, lsa->len);
-#if ENABLE_PING6
+	ping(lsa);
-	if (lsa->sa.sa_family == AF_INET6)
-		ping6(lsa);
-	else
-#endif
-		ping4(lsa);
 	pingstats(0);
 	return EXIT_SUCCESS;
 }