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e76f03b26

Denys Vlasenko

2020-12-12

SUCCESS Duration: 149s

Subject

traceroute: commonalize verbose printing

Binary

No binary (build failed)

Architecture & Compiler Flags

Architecture: x86_64-linux-gnu Compiler: gcc (Ubuntu 11.4.0-1ubuntu1~22.04.3) 11.4.0

—

Build Log

(log yok)

Commit Diff GitHub →

networking/traceroute.c +62 -83

networking/traceroute.c+62 -83

@@ -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());