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traceroute.c

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Last change on this file was 3232, checked in by Bruno Cornec, 10 years ago
Update mindi-busybox to 1.21.1
File size: 37.1 KB

Rev	Line
[821]	1	/* vi: set sw=4 ts=4: */
	2	/*
	3	* Copyright (c) 1988, 1989, 1991, 1994, 1995, 1996, 1997, 1998, 1999, 2000
	4	* The Regents of the University of California. All rights reserved.
	5	*
	6	* Busybox port by Vladimir Oleynik (C) 2005 <dzo@simtreas.ru>
	7	*
	8	* Redistribution and use in source and binary forms, with or without
	9	* modification, are permitted provided that: (1) source code distributions
	10	* retain the above copyright notice and this paragraph in its entirety, (2)
	11	* distributions including binary code include the above copyright notice and
	12	* this paragraph in its entirety in the documentation or other materials
	13	* provided with the distribution, and (3) all advertising materials mentioning
	14	* features or use of this software display the following acknowledgement:
	15	* ``This product includes software developed by the University of California,
	16	* Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
	17	* the University nor the names of its contributors may be used to endorse
	18	* or promote products derived from this software without specific prior
	19	* written permission.
	20	* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
	21	* WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
	22	* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
	23	*/
	24
[2725]	25	/*
	26	* traceroute6
	27	*
	28	* Modified for NRL 4.4BSD IPv6 release.
	29	* 07/31/96 bgp
	30	*
	31	* Modified for Linux IPv6 by Pedro Roque <roque@di.fc.ul.pt>
	32	* 31/07/1996
	33	*
	34	* As ICMP error messages for IPv6 now include more than 8 bytes
	35	* UDP datagrams are now sent via an UDP socket instead of magic
	36	* RAW socket tricks.
	37	*
	38	* Converted to busybox applet by Leonid Lisovskiy <lly@sf.net>
	39	* 2009-11-16
	40	*/
[821]	41
	42	/*
	43	* traceroute host - trace the route ip packets follow going to "host".
	44	*
	45	* Attempt to trace the route an ip packet would follow to some
	46	* internet host. We find out intermediate hops by launching probe
	47	* packets with a small ttl (time to live) then listening for an
	48	* icmp "time exceeded" reply from a gateway. We start our probes
	49	* with a ttl of one and increase by one until we get an icmp "port
	50	* unreachable" (which means we got to "host") or hit a max (which
	51	* defaults to 30 hops & can be changed with the -m flag). Three
	52	* probes (change with -q flag) are sent at each ttl setting and a
	53	* line is printed showing the ttl, address of the gateway and
	54	* round trip time of each probe. If the probe answers come from
	55	* different gateways, the address of each responding system will
	56	* be printed. If there is no response within a 5 sec. timeout
	57	* interval (changed with the -w flag), a "*" is printed for that
	58	* probe.
	59	*
	60	* Probe packets are UDP format. We don't want the destination
	61	* host to process them so the destination port is set to an
	62	* unlikely value (if some clod on the destination is using that
	63	* value, it can be changed with the -p flag).
	64	*
	65	* A sample use might be:
	66	*
	67	* [yak 71]% traceroute nis.nsf.net.
	68	* traceroute to nis.nsf.net (35.1.1.48), 30 hops max, 56 byte packet
	69	* 1 helios.ee.lbl.gov (128.3.112.1) 19 ms 19 ms 0 ms
	70	* 2 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 39 ms 19 ms
	71	* 3 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 39 ms 19 ms
	72	* 4 ccngw-ner-cc.Berkeley.EDU (128.32.136.23) 39 ms 40 ms 39 ms
	73	* 5 ccn-nerif22.Berkeley.EDU (128.32.168.22) 39 ms 39 ms 39 ms
	74	* 6 128.32.197.4 (128.32.197.4) 40 ms 59 ms 59 ms
	75	* 7 131.119.2.5 (131.119.2.5) 59 ms 59 ms 59 ms
	76	* 8 129.140.70.13 (129.140.70.13) 99 ms 99 ms 80 ms
	77	* 9 129.140.71.6 (129.140.71.6) 139 ms 239 ms 319 ms
	78	* 10 129.140.81.7 (129.140.81.7) 220 ms 199 ms 199 ms
	79	* 11 nic.merit.edu (35.1.1.48) 239 ms 239 ms 239 ms
	80	*
	81	* Note that lines 2 & 3 are the same. This is due to a buggy
	82	* kernel on the 2nd hop system -- lbl-csam.arpa -- that forwards
	83	* packets with a zero ttl.
	84	*
	85	* A more interesting example is:
	86	*
	87	* [yak 72]% traceroute allspice.lcs.mit.edu.
	88	* traceroute to allspice.lcs.mit.edu (18.26.0.115), 30 hops max
	89	* 1 helios.ee.lbl.gov (128.3.112.1) 0 ms 0 ms 0 ms
	90	* 2 lilac-dmc.Berkeley.EDU (128.32.216.1) 19 ms 19 ms 19 ms
	91	* 3 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 19 ms 19 ms
	92	* 4 ccngw-ner-cc.Berkeley.EDU (128.32.136.23) 19 ms 39 ms 39 ms
	93	* 5 ccn-nerif22.Berkeley.EDU (128.32.168.22) 20 ms 39 ms 39 ms
	94	* 6 128.32.197.4 (128.32.197.4) 59 ms 119 ms 39 ms
	95	* 7 131.119.2.5 (131.119.2.5) 59 ms 59 ms 39 ms
	96	* 8 129.140.70.13 (129.140.70.13) 80 ms 79 ms 99 ms
	97	* 9 129.140.71.6 (129.140.71.6) 139 ms 139 ms 159 ms
	98	* 10 129.140.81.7 (129.140.81.7) 199 ms 180 ms 300 ms
	99	* 11 129.140.72.17 (129.140.72.17) 300 ms 239 ms 239 ms
	100	* 12 * * *
	101	* 13 128.121.54.72 (128.121.54.72) 259 ms 499 ms 279 ms
	102	* 14 * * *
	103	* 15 * * *
	104	* 16 * * *
	105	* 17 * * *
	106	* 18 ALLSPICE.LCS.MIT.EDU (18.26.0.115) 339 ms 279 ms 279 ms
	107	*
	108	* (I start to see why I'm having so much trouble with mail to
	109	* MIT.) Note that the gateways 12, 14, 15, 16 & 17 hops away
	110	* either don't send ICMP "time exceeded" messages or send them
	111	* with a ttl too small to reach us. 14 - 17 are running the
	112	* MIT C Gateway code that doesn't send "time exceeded"s. God
	113	* only knows what's going on with 12.
	114	*
	115	* The silent gateway 12 in the above may be the result of a bug in
	116	* the 4.[23]BSD network code (and its derivatives): 4.x (x <= 3)
	117	* sends an unreachable message using whatever ttl remains in the
	118	* original datagram. Since, for gateways, the remaining ttl is
	119	* zero, the icmp "time exceeded" is guaranteed to not make it back
	120	* to us. The behavior of this bug is slightly more interesting
	121	* when it appears on the destination system:
	122	*
	123	* 1 helios.ee.lbl.gov (128.3.112.1) 0 ms 0 ms 0 ms
	124	* 2 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 19 ms 39 ms
	125	* 3 lilac-dmc.Berkeley.EDU (128.32.216.1) 19 ms 39 ms 19 ms
	126	* 4 ccngw-ner-cc.Berkeley.EDU (128.32.136.23) 39 ms 40 ms 19 ms
	127	* 5 ccn-nerif35.Berkeley.EDU (128.32.168.35) 39 ms 39 ms 39 ms
	128	* 6 csgw.Berkeley.EDU (128.32.133.254) 39 ms 59 ms 39 ms
	129	* 7 * * *
	130	* 8 * * *
	131	* 9 * * *
	132	* 10 * * *
	133	* 11 * * *
	134	* 12 * * *
	135	* 13 rip.Berkeley.EDU (128.32.131.22) 59 ms ! 39 ms ! 39 ms !
	136	*
	137	* Notice that there are 12 "gateways" (13 is the final
	138	* destination) and exactly the last half of them are "missing".
	139	* What's really happening is that rip (a Sun-3 running Sun OS3.5)
	140	* is using the ttl from our arriving datagram as the ttl in its
	141	* icmp reply. So, the reply will time out on the return path
	142	* (with no notice sent to anyone since icmp's aren't sent for
	143	* icmp's) until we probe with a ttl that's at least twice the path
	144	* length. I.e., rip is really only 7 hops away. A reply that
	145	* returns with a ttl of 1 is a clue this problem exists.
	146	* Traceroute prints a "!" after the time if the ttl is <= 1.
	147	* Since vendors ship a lot of obsolete (DEC's Ultrix, Sun 3.x) or
	148	* non-standard (HPUX) software, expect to see this problem
	149	* frequently and/or take care picking the target host of your
	150	* probes.
	151	*
	152	* Other possible annotations after the time are !H, !N, !P (got a host,
	153	* network or protocol unreachable, respectively), !S or !F (source
	154	* route failed or fragmentation needed -- neither of these should
	155	* ever occur and the associated gateway is busted if you see one). If
	156	* almost all the probes result in some kind of unreachable, traceroute
	157	* will give up and exit.
	158	*
	159	* Notes
	160	* -----
	161	* This program must be run by root or be setuid. (I suggest that
	162	* you don't make it setuid -- casual use could result in a lot
	163	* of unnecessary traffic on our poor, congested nets.)
	164	*
	165	* This program requires a kernel mod that does not appear in any
	166	* system available from Berkeley: A raw ip socket using proto
	167	* IPPROTO_RAW must interpret the data sent as an ip datagram (as
	168	* opposed to data to be wrapped in a ip datagram). See the README
	169	* file that came with the source to this program for a description
	170	* of the mods I made to /sys/netinet/raw_ip.c. Your mileage may
	171	* vary. But, again, ANY 4.x (x < 4) BSD KERNEL WILL HAVE TO BE
	172	* MODIFIED TO RUN THIS PROGRAM.
	173	*
	174	* The udp port usage may appear bizarre (well, ok, it is bizarre).
	175	* The problem is that an icmp message only contains 8 bytes of
	176	* data from the original datagram. 8 bytes is the size of a udp
	177	* header so, if we want to associate replies with the original
	178	* datagram, the necessary information must be encoded into the
	179	* udp header (the ip id could be used but there's no way to
	180	* interlock with the kernel's assignment of ip id's and, anyway,
	181	* it would have taken a lot more kernel hacking to allow this
	182	* code to set the ip id). So, to allow two or more users to
	183	* use traceroute simultaneously, we use this task's pid as the
	184	* source port (the high bit is set to move the port number out
	185	* of the "likely" range). To keep track of which probe is being
	186	* replied to (so times and/or hop counts don't get confused by a
	187	* reply that was delayed in transit), we increment the destination
	188	* port number before each probe.
	189	*
	190	* Don't use this as a coding example. I was trying to find a
	191	* routing problem and this code sort-of popped out after 48 hours
	192	* without sleep. I was amazed it ever compiled, much less ran.
	193	*
	194	* I stole the idea for this program from Steve Deering. Since
	195	* the first release, I've learned that had I attended the right
	196	* IETF working group meetings, I also could have stolen it from Guy
	197	* Almes or Matt Mathis. I don't know (or care) who came up with
	198	* the idea first. I envy the originators' perspicacity and I'm
	199	* glad they didn't keep the idea a secret.
	200	*
	201	* Tim Seaver, Ken Adelman and C. Philip Wood provided bug fixes and/or
	202	* enhancements to the original distribution.
	203	*
	204	* I've hacked up a round-trip-route version of this that works by
	205	* sending a loose-source-routed udp datagram through the destination
	206	* back to yourself. Unfortunately, SO many gateways botch source
	207	* routing, the thing is almost worthless. Maybe one day...
	208	*
	209	* -- Van Jacobson (van@ee.lbl.gov)
	210	* Tue Dec 20 03:50:13 PST 1988
	211	*/
	212
[3232]	213	//usage:#define traceroute_trivial_usage
	214	//usage: "[-"IF_TRACEROUTE6("46")"FIldnrv] [-f 1ST_TTL] [-m MAXTTL] [-p PORT] [-q PROBES]\n"
	215	//usage: " [-s SRC_IP] [-t TOS] [-w WAIT_SEC] [-g GATEWAY] [-i IFACE]\n"
	216	//usage: " [-z PAUSE_MSEC] HOST [BYTES]"
	217	//usage:#define traceroute_full_usage "\n\n"
	218	//usage: "Trace the route to HOST\n"
	219	//usage: IF_TRACEROUTE6(
	220	//usage: "\n -4,-6 Force IP or IPv6 name resolution"
	221	//usage: )
	222	//usage: "\n -F Set the don't fragment bit"
	223	//usage: "\n -I Use ICMP ECHO instead of UDP datagrams"
	224	//usage: "\n -l Display the TTL value of the returned packet"
	225	//usage: "\n -d Set SO_DEBUG options to socket"
	226	//usage: "\n -n Print numeric addresses"
	227	//usage: "\n -r Bypass routing tables, send directly to HOST"
	228	//usage: "\n -v Verbose"
	229	//usage: "\n -m Max time-to-live (max number of hops)"
	230	//usage: "\n -p Base UDP port number used in probes"
	231	//usage: "\n (default 33434)"
	232	//usage: "\n -q Number of probes per TTL (default 3)"
	233	//usage: "\n -s IP address to use as the source address"
	234	//usage: "\n -t Type-of-service in probe packets (default 0)"
	235	//usage: "\n -w Time in seconds to wait for a response (default 3)"
	236	//usage: "\n -g Loose source route gateway (8 max)"
	237	//usage:
	238	//usage:#define traceroute6_trivial_usage
	239	//usage: "[-dnrv] [-m MAXTTL] [-p PORT] [-q PROBES]\n"
	240	//usage: " [-s SRC_IP] [-t TOS] [-w WAIT_SEC] [-i IFACE]\n"
	241	//usage: " HOST [BYTES]"
	242	//usage:#define traceroute6_full_usage "\n\n"
	243	//usage: "Trace the route to HOST\n"
	244	//usage: "\n -d Set SO_DEBUG options to socket"
	245	//usage: "\n -n Print numeric addresses"
	246	//usage: "\n -r Bypass routing tables, send directly to HOST"
	247	//usage: "\n -v Verbose"
	248	//usage: "\n -m Max time-to-live (max number of hops)"
	249	//usage: "\n -p Base UDP port number used in probes"
	250	//usage: "\n (default is 33434)"
	251	//usage: "\n -q Number of probes per TTL (default 3)"
	252	//usage: "\n -s IP address to use as the source address"
	253	//usage: "\n -t Type-of-service in probe packets (default 0)"
	254	//usage: "\n -w Time in seconds to wait for a response (default 3)"
	255
[1765]	256	#define TRACEROUTE_SO_DEBUG 0
	257
	258	/* TODO: undefs were uncommented - ??! we have config system for that! */
	259	/* probably ok to remove altogether */
	260	//#undef CONFIG_FEATURE_TRACEROUTE_VERBOSE
[821]	261	//#define CONFIG_FEATURE_TRACEROUTE_VERBOSE
[1765]	262	//#undef CONFIG_FEATURE_TRACEROUTE_SOURCE_ROUTE
[821]	263	//#define CONFIG_FEATURE_TRACEROUTE_SOURCE_ROUTE
[1765]	264	//#undef CONFIG_FEATURE_TRACEROUTE_USE_ICMP
[821]	265	//#define CONFIG_FEATURE_TRACEROUTE_USE_ICMP
	266
	267
	268	#include <net/if.h>
[1765]	269	#include <arpa/inet.h>
[821]	270	#include <netinet/in.h>
	271	#include <netinet/udp.h>
	272	#include <netinet/ip.h>
	273	#include <netinet/ip_icmp.h>
[2725]	274	#if ENABLE_FEATURE_IPV6
	275	# include <netinet/ip6.h>
	276	# include <netinet/icmp6.h>
	277	# ifndef SOL_IPV6
	278	# define SOL_IPV6 IPPROTO_IPV6
	279	# endif
	280	#endif
[821]	281
[1765]	282	#include "libbb.h"
	283	#include "inet_common.h"
[821]	284
[1765]	285	#ifndef IPPROTO_ICMP
[2725]	286	# define IPPROTO_ICMP 1
[1765]	287	#endif
	288	#ifndef IPPROTO_IP
[2725]	289	# define IPPROTO_IP 0
[1765]	290	#endif
	291
[821]	292
[3232]	293	#define OPT_STRING \
	294	"FIlnrdvxt:i:m:p:q:s:w:z:f:" \
	295	IF_FEATURE_TRACEROUTE_SOURCE_ROUTE("g:") \
	296	"4" IF_TRACEROUTE6("6")
[2725]	297	enum {
	298	OPT_DONT_FRAGMNT = (1 << 0), /* F */
	299	OPT_USE_ICMP = (1 << 1) * ENABLE_FEATURE_TRACEROUTE_USE_ICMP, /* I */
	300	OPT_TTL_FLAG = (1 << 2), /* l */
	301	OPT_ADDR_NUM = (1 << 3), /* n */
	302	OPT_BYPASS_ROUTE = (1 << 4), /* r */
	303	OPT_DEBUG = (1 << 5), /* d */
	304	OPT_VERBOSE = (1 << 6) * ENABLE_FEATURE_TRACEROUTE_VERBOSE, /* v */
	305	OPT_IP_CHKSUM = (1 << 7), /* x */
	306	OPT_TOS = (1 << 8), /* t */
	307	OPT_DEVICE = (1 << 9), /* i */
	308	OPT_MAX_TTL = (1 << 10), /* m */
	309	OPT_PORT = (1 << 11), /* p */
	310	OPT_NPROBES = (1 << 12), /* q */
	311	OPT_SOURCE = (1 << 13), /* s */
	312	OPT_WAITTIME = (1 << 14), /* w */
	313	OPT_PAUSE_MS = (1 << 15), /* z */
	314	OPT_FIRST_TTL = (1 << 16), /* f */
	315	OPT_SOURCE_ROUTE = (1 << 17) * ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE, /* g */
	316	OPT_IPV4 = (1 << (17+ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE)), /* 4 */
	317	OPT_IPV6 = (1 << (18+ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE)) * ENABLE_TRACEROUTE6, /* 6 */
[821]	318	};
[2725]	319	#define verbose (option_mask32 & OPT_VERBOSE)
[821]	320
[2725]	321	enum {
	322	SIZEOF_ICMP_HDR = 8,
	323	rcvsock = 3, /* receive (icmp) socket file descriptor */
	324	sndsock = 4, /* send (udp/icmp) socket file descriptor */
[821]	325	};
	326
	327	/* Data section of the probe packet */
[2725]	328	struct outdata_t {
[821]	329	unsigned char seq; /* sequence number of this packet */
	330	unsigned char ttl; /* ttl packet left with */
[1765]	331	// UNUSED. Retaining to have the same packet size.
[2725]	332	struct timeval tv_UNUSED PACKED; /* time packet left */
[821]	333	};
	334
[2725]	335	#if ENABLE_TRACEROUTE6
	336	struct outdata6_t {
	337	uint32_t ident6;
	338	uint32_t seq6;
	339	struct timeval tv_UNUSED PACKED; /* time packet left */
[821]	340	};
	341	#endif
	342
[2725]	343	struct globals {
	344	struct ip *outip;
	345	struct outdata_t *outdata;
	346	len_and_sockaddr *dest_lsa;
	347	int packlen; /* total length of packet */
	348	int pmtu; /* Path MTU Discovery (RFC1191) */
	349	uint32_t ident;
	350	uint16_t port; // 32768 + 666; /* start udp dest port # for probe packets */
	351	int waittime; // 5; /* time to wait for response (in seconds) */
[1765]	352	#if ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE
[2725]	353	int optlen; /* length of ip options */
[821]	354	#else
	355	#define optlen 0
	356	#endif
[2725]	357	unsigned char recv_pkt[512]; /* last inbound (icmp) packet */
[1765]	358	#if ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE
	359	/* Maximum number of gateways (include room for one noop) */
	360	#define NGATEWAYS ((int)((MAX_IPOPTLEN - IPOPT_MINOFF - 1) / sizeof(uint32_t)))
	361	/* loose source route gateway list (including room for final destination) */
	362	uint32_t gwlist[NGATEWAYS + 1];
	363	#endif
	364	};
	365
	366	#define G (*ptr_to_globals)
[2725]	367	#define outip (G.outip )
	368	#define outdata (G.outdata )
	369	#define dest_lsa (G.dest_lsa )
	370	#define packlen (G.packlen )
	371	#define pmtu (G.pmtu )
	372	#define ident (G.ident )
	373	#define port (G.port )
	374	#define waittime (G.waittime )
	375	#if ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE
	376	# define optlen (G.optlen )
	377	#endif
	378	#define recv_pkt (G.recv_pkt )
[1765]	379	#define gwlist (G.gwlist )
[2725]	380	#define INIT_G() do { \
	381	SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
	382	port = 32768 + 666; \
	383	waittime = 5; \
	384	} while (0)
[1765]	385
[2725]	386	#define outicmp ((struct icmp *)(outip + 1))
	387	#define outudp ((struct udphdr *)(outip + 1))
[1765]	388
	389
[2725]	390	/* libbb candidate? tftp uses this idiom too */
	391	static len_and_sockaddr* dup_sockaddr(const len_and_sockaddr *lsa)
[821]	392	{
[2725]	393	len_and_sockaddr *new_lsa = xzalloc(LSA_LEN_SIZE + lsa->len);
	394	memcpy(new_lsa, lsa, LSA_LEN_SIZE + lsa->len);
	395	return new_lsa;
[821]	396	}
	397
	398
[2725]	399	static int
[3232]	400	wait_for_reply(len_and_sockaddr from_lsa, struct sockaddr to, unsigned timestamp_us, int left_ms)
[821]	401	{
[2725]	402	struct pollfd pfd[1];
	403	int read_len = 0;
[821]	404
[2725]	405	pfd[0].fd = rcvsock;
	406	pfd[0].events = POLLIN;
[3232]	407	if (left_ms >= 0 && safe_poll(pfd, 1, left_ms) > 0) {
	408	unsigned t;
	409
[2725]	410	read_len = recv_from_to(rcvsock,
	411	recv_pkt, sizeof(recv_pkt),
[3232]	412	/flags:/ MSG_DONTWAIT,
[2725]	413	&from_lsa->u.sa, to, from_lsa->len);
[3232]	414	t = monotonic_us();
	415	left_ms -= (t - timestamp_us) / 1000;
	416	*timestamp_us = t;
[821]	417	}
	418
[2725]	419	return read_len;
[821]	420	}
	421
	422	static void
[1765]	423	send_probe(int seq, int ttl)
[821]	424	{
[2725]	425	int len, res;
	426	void *out;
[821]	427
	428	/* Payload */
[2725]	429	#if ENABLE_TRACEROUTE6
	430	if (dest_lsa->u.sa.sa_family == AF_INET6) {
	431	struct outdata6_t pkt = (struct outdata6_t ) outip;
	432	pkt->ident6 = htonl(ident);
	433	pkt->seq6 = htonl(seq);
	434	/gettimeofday(&pkt->tv, &tz);/
	435	} else
	436	#endif
	437	{
	438	outdata->seq = seq;
	439	outdata->ttl = ttl;
[1765]	440	// UNUSED: was storing gettimeofday's result there, but never ever checked it
[2725]	441	/memcpy(&outdata->tv, tp, sizeof(outdata->tv));/
[821]	442
[2725]	443	if (option_mask32 & OPT_USE_ICMP) {
	444	outicmp->icmp_seq = htons(seq);
[821]	445
[2725]	446	/* Always calculate checksum for icmp packets */
	447	outicmp->icmp_cksum = 0;
[3232]	448	outicmp->icmp_cksum = inet_cksum((uint16_t *)outicmp,
[2725]	449	packlen - (sizeof(*outip) + optlen));
	450	if (outicmp->icmp_cksum == 0)
	451	outicmp->icmp_cksum = 0xffff;
	452	}
[821]	453	}
	454
[2725]	455	//BUG! verbose is (x & OPT_VERBOSE), not a counter!
	456	#if 0 //ENABLE_FEATURE_TRACEROUTE_VERBOSE
[821]	457	/* XXX undocumented debugging hack */
	458	if (verbose > 1) {
[1765]	459	const uint16_t *sp;
[821]	460	int nshorts, i;
	461
[1765]	462	sp = (uint16_t *)outip;
	463	nshorts = (unsigned)packlen / sizeof(uint16_t);
[821]	464	i = 0;
	465	printf("[ %d bytes", packlen);
	466	while (--nshorts >= 0) {
	467	if ((i++ % 8) == 0)
	468	printf("\n\t");
	469	printf(" %04x", ntohs(*sp));
	470	sp++;
	471	}
	472	if (packlen & 1) {
	473	if ((i % 8) == 0)
	474	printf("\n\t");
	475	printf(" %02x", (unsigned char )sp);
	476	}
	477	printf("]\n");
	478	}
	479	#endif
	480
[2725]	481	#if ENABLE_TRACEROUTE6
	482	if (dest_lsa->u.sa.sa_family == AF_INET6) {
	483	res = setsockopt(sndsock, SOL_IPV6, IPV6_UNICAST_HOPS, &ttl, sizeof(ttl));
	484	if (res < 0)
	485	bb_perror_msg_and_die("setsockopt UNICAST_HOPS %d", ttl);
	486	out = outip;
	487	len = packlen;
	488	} else
	489	#endif
	490	{
	491	#if defined IP_TTL
	492	res = setsockopt(sndsock, IPPROTO_IP, IP_TTL, &ttl, sizeof(ttl));
	493	if (res < 0)
	494	bb_perror_msg_and_die("setsockopt ttl %d", ttl);
	495	#endif
	496	out = outicmp;
	497	len = packlen - sizeof(*outip);
	498	if (!(option_mask32 & OPT_USE_ICMP)) {
	499	out = outdata;
	500	len -= sizeof(*outudp);
[3232]	501	set_nport(&dest_lsa->u.sa, htons(port + seq));
[2725]	502	}
[821]	503	}
	504
[2725]	505	res = xsendto(sndsock, out, len, &dest_lsa->u.sa, dest_lsa->len);
	506	if (res != len)
	507	bb_info_msg("sent %d octets, ret=%d", len, res);
[821]	508	}
	509
[1765]	510	#if ENABLE_FEATURE_TRACEROUTE_VERBOSE
[821]	511	/*
	512	* Convert an ICMP "type" field to a printable string.
	513	*/
[2725]	514	static const char *
[821]	515	pr_type(unsigned char t)
	516	{
[1765]	517	static const char *const ttab[] = {
[821]	518	"Echo Reply", "ICMP 1", "ICMP 2", "Dest Unreachable",
	519	"Source Quench", "Redirect", "ICMP 6", "ICMP 7",
	520	"Echo", "Router Advert", "Router Solicit", "Time Exceeded",
	521	"Param Problem", "Timestamp", "Timestamp Reply", "Info Request",
	522	"Info Reply", "Mask Request", "Mask Reply"
	523	};
[2725]	524	# if ENABLE_TRACEROUTE6
	525	static const char *const ttab6[] = {
	526	[0] "Error", "Dest Unreachable", "Packet Too Big", "Time Exceeded",
	527	[4] "Param Problem",
	528	[8] "Echo Request", "Echo Reply", "Membership Query", "Membership Report",
	529	[12] "Membership Reduction", "Router Solicit", "Router Advert", "Neighbor Solicit",
	530	[16] "Neighbor Advert", "Redirect",
	531	};
[821]	532
[2725]	533	if (dest_lsa->u.sa.sa_family == AF_INET6) {
	534	if (t < 5)
	535	return ttab6[t];
	536	if (t < 128 \|\| t > ND_REDIRECT)
	537	return "OUT-OF-RANGE";
	538	return ttab6[(t & 63) + 8];
	539	}
	540	# endif
	541	if (t >= ARRAY_SIZE(ttab))
[821]	542	return "OUT-OF-RANGE";
	543
	544	return ttab[t];
	545	}
	546	#endif
	547
[2725]	548	#if !ENABLE_FEATURE_TRACEROUTE_VERBOSE
	549	#define packet4_ok(read_len, from, seq) \
	550	packet4_ok(read_len, seq)
	551	#endif
[821]	552	static int
[2725]	553	packet4_ok(int read_len, const struct sockaddr_in *from, int seq)
[821]	554	{
[2725]	555	const struct icmp *icp;
[821]	556	unsigned char type, code;
	557	int hlen;
[2725]	558	const struct ip *ip;
[821]	559
[2725]	560	ip = (struct ip *) recv_pkt;
[821]	561	hlen = ip->ip_hl << 2;
[2725]	562	if (read_len < hlen + ICMP_MINLEN) {
[1765]	563	#if ENABLE_FEATURE_TRACEROUTE_VERBOSE
[821]	564	if (verbose)
[2725]	565	printf("packet too short (%d bytes) from %s\n", read_len,
[821]	566	inet_ntoa(from->sin_addr));
	567	#endif
	568	return 0;
	569	}
[2725]	570	read_len -= hlen;
	571	icp = (struct icmp *)(recv_pkt + hlen);
[821]	572	type = icp->icmp_type;
	573	code = icp->icmp_code;
	574	/* Path MTU Discovery (RFC1191) */
[2725]	575	pmtu = 0;
	576	if (code == ICMP_UNREACH_NEEDFRAG)
[821]	577	pmtu = ntohs(icp->icmp_nextmtu);
	578
[2725]	579	if ((type == ICMP_TIMXCEED && code == ICMP_TIMXCEED_INTRANS)
	580	\|\| type == ICMP_UNREACH
	581	\|\| type == ICMP_ECHOREPLY
	582	) {
	583	const struct ip *hip;
	584	const struct udphdr *up;
	585
[821]	586	hip = &icp->icmp_ip;
	587	hlen = hip->ip_hl << 2;
[2725]	588	if (option_mask32 & OPT_USE_ICMP) {
[821]	589	struct icmp *hicmp;
	590
	591	/* XXX */
[2725]	592	if (type == ICMP_ECHOREPLY
	593	&& icp->icmp_id == htons(ident)
	594	&& icp->icmp_seq == htons(seq)
	595	) {
	596	return ICMP_UNREACH_PORT+1;
	597	}
[821]	598
	599	hicmp = (struct icmp )((unsigned char )hip + hlen);
[2725]	600	if (hlen + SIZEOF_ICMP_HDR <= read_len
	601	&& hip->ip_p == IPPROTO_ICMP
	602	&& hicmp->icmp_id == htons(ident)
	603	&& hicmp->icmp_seq == htons(seq)
	604	) {
[821]	605	return (type == ICMP_TIMXCEED ? -1 : code + 1);
[2725]	606	}
	607	} else {
	608	up = (struct udphdr )((char )hip + hlen);
	609	if (hlen + 12 <= read_len
	610	&& hip->ip_p == IPPROTO_UDP
	611	// Off: since we do not form the entire IP packet,
	612	// but defer it to kernel, we can't set source port,
	613	// and thus can't check it here in the reply
	614	/* && up->source == htons(ident) */
	615	&& up->dest == htons(port + seq)
	616	) {
[821]	617	return (type == ICMP_TIMXCEED ? -1 : code + 1);
[2725]	618	}
[821]	619	}
	620	}
[1765]	621	#if ENABLE_FEATURE_TRACEROUTE_VERBOSE
[821]	622	if (verbose) {
	623	int i;
[1765]	624	uint32_t lp = (uint32_t )&icp->icmp_ip;
[821]	625
	626	printf("\n%d bytes from %s to "
	627	"%s: icmp type %d (%s) code %d\n",
[2725]	628	read_len, inet_ntoa(from->sin_addr),
	629	inet_ntoa(ip->ip_dst),
	630	type, pr_type(type), icp->icmp_code);
	631	for (i = 4; i < read_len; i += sizeof(*lp))
[821]	632	printf("%2d: x%8.8x\n", i, *lp++);
	633	}
	634	#endif
	635	return 0;
	636	}
	637
[2725]	638	#if ENABLE_TRACEROUTE6
	639	# if !ENABLE_FEATURE_TRACEROUTE_VERBOSE
	640	#define packet_ok(read_len, from_lsa, to, seq) \
	641	packet_ok(read_len, from_lsa, seq)
	642	# endif
	643	static int
	644	packet_ok(int read_len, len_and_sockaddr *from_lsa,
	645	struct sockaddr *to,
	646	int seq)
[821]	647	{
[2725]	648	const struct icmp6_hdr *icp;
	649	unsigned char type, code;
[821]	650
[2725]	651	if (from_lsa->u.sa.sa_family == AF_INET)
	652	return packet4_ok(read_len, &from_lsa->u.sin, seq);
[821]	653
[2725]	654	icp = (struct icmp6_hdr *) recv_pkt;
[821]	655
[2725]	656	type = icp->icmp6_type;
	657	code = icp->icmp6_code;
[821]	658
[2725]	659	if ((type == ICMP6_TIME_EXCEEDED && code == ICMP6_TIME_EXCEED_TRANSIT)
	660	\|\| type == ICMP6_DST_UNREACH
	661	) {
	662	struct ip6_hdr *hip;
	663	struct udphdr *up;
	664	int nexthdr;
[821]	665
[2725]	666	hip = (struct ip6_hdr *)(icp + 1);
	667	up = (struct udphdr *) (hip + 1);
	668	nexthdr = hip->ip6_nxt;
[821]	669
[2725]	670	if (nexthdr == IPPROTO_FRAGMENT) {
	671	nexthdr = (unsigned char)up;
	672	up++;
	673	}
	674	if (nexthdr == IPPROTO_UDP) {
	675	struct outdata6_t *pkt;
[821]	676
[2725]	677	pkt = (struct outdata6_t *) (up + 1);
	678
	679	if (ntohl(pkt->ident6) == ident
	680	&& ntohl(pkt->seq6) == seq
	681	) {
	682	return (type == ICMP6_TIME_EXCEEDED ? -1 : (code<<8)+1);
	683	}
	684	}
[821]	685	}
	686
[2725]	687	# if ENABLE_FEATURE_TRACEROUTE_VERBOSE
	688	if (verbose) {
	689	unsigned char *p;
	690	char pa1[MAXHOSTNAMELEN];
	691	char pa2[MAXHOSTNAMELEN];
	692	int i;
	693
	694	p = (unsigned char *) (icp + 1);
	695
	696	printf("\n%d bytes from %s to "
	697	"%s: icmp type %d (%s) code %d\n",
	698	read_len,
	699	inet_ntop(AF_INET6, &from_lsa->u.sin6.sin6_addr, pa1, sizeof(pa1)),
	700	inet_ntop(AF_INET6, &((struct sockaddr_in6*)to)->sin6_addr, pa2, sizeof(pa2)),
	701	type, pr_type(type), icp->icmp6_code);
	702
	703	read_len -= sizeof(struct icmp6_hdr);
[3232]	704	for (i = 0; i < read_len; i++) {
[2725]	705	if (i % 16 == 0)
	706	printf("%04x:", i);
	707	if (i % 4 == 0)
	708	bb_putchar(' ');
	709	printf("%02x", p[i]);
	710	if ((i % 16 == 15) && (i + 1 < read_len))
	711	bb_putchar('\n');
	712	}
	713	bb_putchar('\n');
	714	}
	715	# endif
	716
	717	return 0;
[821]	718	}
[2725]	719	#else /* !ENABLE_TRACEROUTE6 */
	720	static ALWAYS_INLINE int
	721	packet_ok(int read_len,
	722	len_and_sockaddr *from_lsa IF_NOT_FEATURE_TRACEROUTE_VERBOSE(UNUSED_PARAM),
	723	struct sockaddr *to UNUSED_PARAM,
	724	int seq)
	725	{
	726	return packet4_ok(read_len, &from_lsa->u.sin, seq);
	727	}
	728	#endif
[821]	729
[2725]	730	/*
	731	* Construct an Internet address representation.
	732	* If the -n flag has been supplied, give
	733	* numeric value, otherwise try for symbolic name.
	734	*/
[821]	735	static void
[2725]	736	print_inetname(const struct sockaddr *from)
[821]	737	{
[2725]	738	char *ina = xmalloc_sockaddr2dotted_noport(from);
	739
	740	if (option_mask32 & OPT_ADDR_NUM) {
	741	printf(" %s", ina);
	742	} else {
	743	char *n = NULL;
	744
	745	if (from->sa_family != AF_INET
	746	\|\| ((struct sockaddr_in*)from)->sin_addr.s_addr != INADDR_ANY
	747	) {
	748	/* Try to reverse resolve if it is not 0.0.0.0 */
	749	n = xmalloc_sockaddr2host_noport((struct sockaddr*)from);
	750	}
	751	printf(" %s (%s)", (n ? n : ina), ina);
	752	free(n);
	753	}
	754	free(ina);
[821]	755	}
	756
	757	static void
[2725]	758	print(int read_len, const struct sockaddr from, const struct sockaddr to)
[821]	759	{
[2725]	760	print_inetname(from);
[821]	761
[2725]	762	if (verbose) {
	763	char *ina = xmalloc_sockaddr2dotted_noport(to);
	764	#if ENABLE_TRACEROUTE6
	765	if (to->sa_family == AF_INET6) {
	766	read_len -= sizeof(struct ip6_hdr);
	767	} else
	768	#endif
	769	{
[3232]	770	struct ip ip4packet = (struct ip)recv_pkt;
	771	read_len -= ip4packet->ip_hl << 2;
[2725]	772	}
	773	printf(" %d bytes to %s", read_len, ina);
	774	free(ina);
	775	}
[821]	776	}
	777
[1765]	778	static void
	779	print_delta_ms(unsigned t1p, unsigned t2p)
	780	{
	781	unsigned tt = t2p - t1p;
[2725]	782	printf(" %u.%03u ms", tt / 1000, tt % 1000);
[1765]	783	}
[821]	784
[2725]	785	/*
	786	* Usage: [-dFIlnrvx] [-g gateway] [-i iface] [-f first_ttl]
	787	* [-m max_ttl] [ -p port] [-q nqueries] [-s src_addr] [-t tos]
	788	* [-w waittime] [-z pausemsecs] host [packetlen]"
	789	*/
	790	static int
	791	common_traceroute_main(int op, char **argv)
[821]	792	{
[2725]	793	int minpacket;
[821]	794	int tos = 0;
[2725]	795	int max_ttl = 30;
	796	int nprobes = 3;
	797	int first_ttl = 1;
	798	unsigned pausemsecs = 0;
[1765]	799	char *source;
	800	char *device;
[2725]	801	char *tos_str;
[1765]	802	char *max_ttl_str;
	803	char *port_str;
	804	char *nprobes_str;
	805	char *waittime_str;
	806	char *pausemsecs_str;
	807	char *first_ttl_str;
	808	#if ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE
	809	llist_t *source_route_list = NULL;
[2725]	810	int lsrr = 0;
[821]	811	#endif
[2725]	812	#if ENABLE_TRACEROUTE6
	813	sa_family_t af;
[821]	814	#else
[2725]	815	enum { af = AF_INET };
[821]	816	#endif
[2725]	817	int ttl;
	818	int seq;
	819	len_and_sockaddr *from_lsa;
	820	struct sockaddr *lastaddr;
	821	struct sockaddr *to;
[821]	822
[2725]	823	INIT_G();
	824
	825	/* minimum 1 arg */
	826	opt_complementary = "-1:x-x" IF_FEATURE_TRACEROUTE_SOURCE_ROUTE(":g::");
	827	op \|= getopt32(argv, OPT_STRING
[1765]	828	, &tos_str, &device, &max_ttl_str, &port_str, &nprobes_str
	829	, &source, &waittime_str, &pausemsecs_str, &first_ttl_str
	830	#if ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE
	831	, &source_route_list
[821]	832	#endif
	833	);
[2725]	834	argv += optind;
[821]	835
[2725]	836	#if 0 /* IGNORED */
	837	if (op & OPT_IP_CHKSUM)
[1765]	838	bb_error_msg("warning: ip checksums disabled");
[2725]	839	#endif
[1765]	840	if (op & OPT_TOS)
	841	tos = xatou_range(tos_str, 0, 255);
	842	if (op & OPT_MAX_TTL)
	843	max_ttl = xatou_range(max_ttl_str, 1, 255);
	844	if (op & OPT_PORT)
	845	port = xatou16(port_str);
	846	if (op & OPT_NPROBES)
	847	nprobes = xatou_range(nprobes_str, 1, INT_MAX);
	848	if (op & OPT_SOURCE) {
	849	/*
	850	* set the ip source address of the outbound
	851	* probe (e.g., on a multi-homed host).
	852	*/
[2725]	853	if (getuid() != 0)
	854	bb_error_msg_and_die(bb_msg_you_must_be_root);
[821]	855	}
[1765]	856	if (op & OPT_WAITTIME)
[2725]	857	waittime = xatou_range(waittime_str, 1, 24 * 60 * 60);
[1765]	858	if (op & OPT_PAUSE_MS)
	859	pausemsecs = xatou_range(pausemsecs_str, 0, 60 * 60 * 1000);
	860	if (op & OPT_FIRST_TTL)
[2725]	861	first_ttl = xatou_range(first_ttl_str, 1, max_ttl);
[821]	862
[1765]	863	#if ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE
	864	if (source_route_list) {
[2725]	865	while (source_route_list) {
	866	len_and_sockaddr *lsa;
[821]	867
	868	if (lsrr >= NGATEWAYS)
[1765]	869	bb_error_msg_and_die("no more than %d gateways", NGATEWAYS);
[2725]	870	lsa = xhost_and_af2sockaddr(llist_pop(&source_route_list), 0, AF_INET);
	871	gwlist[lsrr] = lsa->u.sin.sin_addr.s_addr;
	872	free(lsa);
[821]	873	++lsrr;
	874	}
	875	optlen = (lsrr + 1) * sizeof(gwlist[0]);
	876	}
	877	#endif
	878
[2725]	879	/* Process destination and optional packet size */
	880	minpacket = sizeof(outip) + SIZEOF_ICMP_HDR + sizeof(outdata) + optlen;
	881	if (!(op & OPT_USE_ICMP))
	882	minpacket += sizeof(*outudp) - SIZEOF_ICMP_HDR;
	883	#if ENABLE_TRACEROUTE6
	884	af = AF_UNSPEC;
	885	if (op & OPT_IPV4)
	886	af = AF_INET;
	887	if (op & OPT_IPV6)
	888	af = AF_INET6;
	889	dest_lsa = xhost_and_af2sockaddr(argv[0], port, af);
	890	af = dest_lsa->u.sa.sa_family;
	891	if (af == AF_INET6)
	892	minpacket = sizeof(struct outdata6_t);
	893	#else
	894	dest_lsa = xhost2sockaddr(argv[0], port);
[821]	895	#endif
[2725]	896	packlen = minpacket;
	897	if (argv[1])
	898	packlen = xatoul_range(argv[1], minpacket, 32 * 1024);
[821]	899
[1765]	900	/* Ensure the socket fds won't be 0, 1 or 2 */
	901	bb_sanitize_stdio();
[821]	902
[2725]	903	#if ENABLE_TRACEROUTE6
	904	if (af == AF_INET6) {
	905	xmove_fd(xsocket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6), rcvsock);
	906	# ifdef IPV6_RECVPKTINFO
	907	setsockopt(rcvsock, SOL_IPV6, IPV6_RECVPKTINFO,
	908	&const_int_1, sizeof(const_int_1));
	909	setsockopt(rcvsock, SOL_IPV6, IPV6_2292PKTINFO,
	910	&const_int_1, sizeof(const_int_1));
	911	# else
	912	setsockopt(rcvsock, SOL_IPV6, IPV6_PKTINFO,
	913	&const_int_1, sizeof(const_int_1));
	914	# endif
	915	} else
	916	#endif
	917	{
	918	xmove_fd(xsocket(AF_INET, SOCK_RAW, IPPROTO_ICMP), rcvsock);
	919	}
[821]	920
[1765]	921	#if TRACEROUTE_SO_DEBUG
	922	if (op & OPT_DEBUG)
[2725]	923	setsockopt(rcvsock, SOL_SOCKET, SO_DEBUG,
[1765]	924	&const_int_1, sizeof(const_int_1));
[821]	925	#endif
[1765]	926	if (op & OPT_BYPASS_ROUTE)
[2725]	927	setsockopt(rcvsock, SOL_SOCKET, SO_DONTROUTE,
[1765]	928	&const_int_1, sizeof(const_int_1));
[821]	929
[2725]	930	#if ENABLE_TRACEROUTE6
	931	if (af == AF_INET6) {
	932	static const int two = 2;
	933	if (setsockopt(rcvsock, SOL_RAW, IPV6_CHECKSUM, &two, sizeof(two)) < 0)
	934	bb_perror_msg_and_die("setsockopt RAW_CHECKSUM");
	935	xmove_fd(xsocket(af, SOCK_DGRAM, 0), sndsock);
	936	} else
	937	#endif
	938	{
	939	if (op & OPT_USE_ICMP)
	940	xmove_fd(xsocket(AF_INET, SOCK_RAW, IPPROTO_ICMP), sndsock);
	941	else
	942	xmove_fd(xsocket(AF_INET, SOCK_DGRAM, 0), sndsock);
	943	#if ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE && defined IP_OPTIONS
	944	if (lsrr > 0) {
	945	unsigned char optlist[MAX_IPOPTLEN];
[3232]	946	unsigned size;
[821]	947
[2725]	948	/* final hop */
	949	gwlist[lsrr] = dest_lsa->u.sin.sin_addr.s_addr;
	950	++lsrr;
[821]	951
[2725]	952	/* force 4 byte alignment */
	953	optlist[0] = IPOPT_NOP;
	954	/* loose source route option */
	955	optlist[1] = IPOPT_LSRR;
[3232]	956	size = lsrr * sizeof(gwlist[0]);
	957	optlist[2] = size + 3;
[2725]	958	/* pointer to LSRR addresses */
	959	optlist[3] = IPOPT_MINOFF;
[3232]	960	memcpy(optlist + 4, gwlist, size);
[821]	961
[2725]	962	if (setsockopt(sndsock, IPPROTO_IP, IP_OPTIONS,
[3232]	963	(char *)optlist, size + sizeof(gwlist[0])) < 0) {
[2725]	964	bb_perror_msg_and_die("IP_OPTIONS");
	965	}
[1765]	966	}
[2725]	967	#endif
[821]	968	}
	969
	970	#ifdef SO_SNDBUF
[1765]	971	if (setsockopt(sndsock, SOL_SOCKET, SO_SNDBUF, &packlen, sizeof(packlen)) < 0) {
[821]	972	bb_perror_msg_and_die("SO_SNDBUF");
	973	}
	974	#endif
	975	#ifdef IP_TOS
[2725]	976	if ((op & OPT_TOS) && setsockopt(sndsock, IPPROTO_IP, IP_TOS, &tos, sizeof(tos)) < 0) {
[821]	977	bb_perror_msg_and_die("setsockopt tos %d", tos);
	978	}
	979	#endif
[2725]	980	#ifdef IP_DONTFRAG
	981	if (op & OPT_DONT_FRAGMNT)
	982	setsockopt(sndsock, IPPROTO_IP, IP_DONTFRAG,
	983	&const_int_1, sizeof(const_int_1));
[821]	984	#endif
[1765]	985	#if TRACEROUTE_SO_DEBUG
	986	if (op & OPT_DEBUG)
	987	setsockopt(sndsock, SOL_SOCKET, SO_DEBUG,
	988	&const_int_1, sizeof(const_int_1));
[821]	989	#endif
[1765]	990	if (op & OPT_BYPASS_ROUTE)
	991	setsockopt(sndsock, SOL_SOCKET, SO_DONTROUTE,
	992	&const_int_1, sizeof(const_int_1));
[821]	993
[1765]	994	outip = xzalloc(packlen);
[821]	995
[2725]	996	ident = getpid();
[821]	997
[2725]	998	if (af == AF_INET) {
	999	if (op & OPT_USE_ICMP) {
	1000	ident \|= 0x8000;
	1001	outicmp->icmp_type = ICMP_ECHO;
	1002	outicmp->icmp_id = htons(ident);
	1003	outdata = (struct outdata_t )((char )outicmp + SIZEOF_ICMP_HDR);
	1004	} else {
	1005	outdata = (struct outdata_t *)(outudp + 1);
	1006	}
[821]	1007	}
	1008
[2725]	1009	if (op & OPT_DEVICE) /* hmm, do we need error check? */
	1010	setsockopt_bindtodevice(sndsock, device);
[821]	1011
[2725]	1012	if (op & OPT_SOURCE) {
	1013	#if ENABLE_TRACEROUTE6
	1014	// TODO: need xdotted_and_af2sockaddr?
	1015	len_and_sockaddr *source_lsa = xhost_and_af2sockaddr(source, 0, af);
	1016	#else
	1017	len_and_sockaddr *source_lsa = xdotted2sockaddr(source, 0);
	1018	#endif
	1019	/* Ping4 does this (why?) */
	1020	if (af == AF_INET)
	1021	if (setsockopt(sndsock, IPPROTO_IP, IP_MULTICAST_IF,
	1022	&source_lsa->u.sa, source_lsa->len))
	1023	bb_error_msg_and_die("can't set multicast source interface");
	1024	//TODO: we can query source port we bound to,
	1025	// and check it in replies... if we care enough
	1026	xbind(sndsock, &source_lsa->u.sa, source_lsa->len);
	1027	free(source_lsa);
[821]	1028	}
[2725]	1029	#if ENABLE_TRACEROUTE6
	1030	else if (af == AF_INET6) {
	1031	//TODO: why we don't do it for IPv4?
	1032	len_and_sockaddr *source_lsa;
[821]	1033
[2725]	1034	int probe_fd = xsocket(af, SOCK_DGRAM, 0);
[1765]	1035	if (op & OPT_DEVICE)
[2725]	1036	setsockopt_bindtodevice(probe_fd, device);
[3232]	1037	set_nport(&dest_lsa->u.sa, htons(1025));
[2725]	1038	/* dummy connect. makes kernel pick source IP (and port) */
	1039	xconnect(probe_fd, &dest_lsa->u.sa, dest_lsa->len);
[3232]	1040	set_nport(&dest_lsa->u.sa, htons(port));
[2725]	1041
	1042	/* read IP and port */
	1043	source_lsa = get_sock_lsa(probe_fd);
	1044	if (source_lsa == NULL)
	1045	bb_error_msg_and_die("can't get probe addr");
	1046
	1047	close(probe_fd);
	1048
	1049	/* bind our sockets to this IP (but not port) */
[3232]	1050	set_nport(&source_lsa->u.sa, 0);
[2725]	1051	xbind(sndsock, &source_lsa->u.sa, source_lsa->len);
	1052	xbind(rcvsock, &source_lsa->u.sa, source_lsa->len);
	1053
	1054	free(source_lsa);
[821]	1055	}
	1056	#endif
	1057
[2725]	1058	/* Revert to non-privileged user after opening sockets */
	1059	xsetgid(getgid());
	1060	xsetuid(getuid());
	1061
	1062	printf("traceroute to %s (%s)", argv[0],
	1063	xmalloc_sockaddr2dotted_noport(&dest_lsa->u.sa));
[1765]	1064	if (op & OPT_SOURCE)
	1065	printf(" from %s", source);
	1066	printf(", %d hops max, %d byte packets\n", max_ttl, packlen);
[821]	1067
[2725]	1068	from_lsa = dup_sockaddr(dest_lsa);
	1069	lastaddr = xzalloc(dest_lsa->len);
	1070	to = xzalloc(dest_lsa->len);
	1071	seq = 0;
[821]	1072	for (ttl = first_ttl; ttl <= max_ttl; ++ttl) {
[2725]	1073	int probe;
	1074	int unreachable = 0; /* counter */
	1075	int gotlastaddr = 0; /* flags */
[821]	1076	int got_there = 0;
	1077
[2725]	1078	printf("%2d", ttl);
[821]	1079	for (probe = 0; probe < nprobes; ++probe) {
[2725]	1080	int read_len;
[1765]	1081	unsigned t1;
	1082	unsigned t2;
[3232]	1083	int left_ms;
[821]	1084	struct ip *ip;
	1085
[3232]	1086	fflush_all();
	1087	if (probe != 0 && pausemsecs > 0)
[821]	1088	usleep(pausemsecs * 1000);
[2725]	1089
[1765]	1090	send_probe(++seq, ttl);
[3232]	1091	t2 = t1 = monotonic_us();
[2725]	1092
[3232]	1093	left_ms = waittime * 1000;
	1094	while ((read_len = wait_for_reply(from_lsa, to, &t2, &left_ms)) != 0) {
	1095	int icmp_code;
	1096
	1097	/* Recv'ed a packet, or read error */
	1098	/* t2 = monotonic_us() - set by wait_for_reply */
	1099
	1100	if (read_len < 0)
	1101	continue;
	1102	icmp_code = packet_ok(read_len, from_lsa, to, seq);
[821]	1103	/* Skip short packet */
[3232]	1104	if (icmp_code == 0)
[821]	1105	continue;
[2725]	1106
	1107	if (!gotlastaddr
	1108	\|\| (memcmp(lastaddr, &from_lsa->u.sa, from_lsa->len) != 0)
	1109	) {
	1110	print(read_len, &from_lsa->u.sa, to);
	1111	memcpy(lastaddr, &from_lsa->u.sa, from_lsa->len);
	1112	gotlastaddr = 1;
[821]	1113	}
[2725]	1114
[1765]	1115	print_delta_ms(t1, t2);
[2725]	1116	ip = (struct ip *)recv_pkt;
	1117
	1118	if (from_lsa->u.sa.sa_family == AF_INET)
	1119	if (op & OPT_TTL_FLAG)
	1120	printf(" (%d)", ip->ip_ttl);
	1121
[821]	1122	/* time exceeded in transit */
[3232]	1123	if (icmp_code == -1)
[821]	1124	break;
[3232]	1125	icmp_code--;
	1126	switch (icmp_code) {
[2725]	1127	#if ENABLE_TRACEROUTE6
	1128	case ICMP6_DST_UNREACH_NOPORT << 8:
	1129	got_there = 1;
	1130	break;
	1131	#endif
[821]	1132	case ICMP_UNREACH_PORT:
	1133	if (ip->ip_ttl <= 1)
	1134	printf(" !");
[2725]	1135	got_there = 1;
[821]	1136	break;
	1137
	1138	case ICMP_UNREACH_NET:
[2725]	1139	#if ENABLE_TRACEROUTE6 && (ICMP6_DST_UNREACH_NOROUTE != ICMP_UNREACH_NET)
	1140	case ICMP6_DST_UNREACH_NOROUTE << 8:
	1141	#endif
	1142	printf(" !N");
[821]	1143	++unreachable;
	1144	break;
	1145	case ICMP_UNREACH_HOST:
[2725]	1146	#if ENABLE_TRACEROUTE6
	1147	case ICMP6_DST_UNREACH_ADDR << 8:
	1148	#endif
	1149	printf(" !H");
[821]	1150	++unreachable;
	1151	break;
	1152	case ICMP_UNREACH_PROTOCOL:
	1153	printf(" !P");
[2725]	1154	got_there = 1;
[821]	1155	break;
	1156	case ICMP_UNREACH_NEEDFRAG:
[2725]	1157	printf(" !F-%d", pmtu);
[821]	1158	++unreachable;
	1159	break;
	1160	case ICMP_UNREACH_SRCFAIL:
[2725]	1161	#if ENABLE_TRACEROUTE6
	1162	case ICMP6_DST_UNREACH_ADMIN << 8:
	1163	#endif
	1164	printf(" !S");
[821]	1165	++unreachable;
	1166	break;
	1167	case ICMP_UNREACH_FILTER_PROHIB:
	1168	case ICMP_UNREACH_NET_PROHIB: /* misuse */
[2725]	1169	printf(" !A");
[821]	1170	++unreachable;
	1171	break;
	1172	case ICMP_UNREACH_HOST_PROHIB:
[2725]	1173	printf(" !C");
[821]	1174	++unreachable;
	1175	break;
	1176	case ICMP_UNREACH_HOST_PRECEDENCE:
[2725]	1177	printf(" !V");
[821]	1178	++unreachable;
	1179	break;
	1180	case ICMP_UNREACH_PRECEDENCE_CUTOFF:
[2725]	1181	printf(" !C");
[821]	1182	++unreachable;
	1183	break;
	1184	case ICMP_UNREACH_NET_UNKNOWN:
	1185	case ICMP_UNREACH_HOST_UNKNOWN:
[2725]	1186	printf(" !U");
[821]	1187	++unreachable;
	1188	break;
	1189	case ICMP_UNREACH_ISOLATED:
[2725]	1190	printf(" !I");
[821]	1191	++unreachable;
	1192	break;
	1193	case ICMP_UNREACH_TOSNET:
	1194	case ICMP_UNREACH_TOSHOST:
[2725]	1195	printf(" !T");
[821]	1196	++unreachable;
	1197	break;
	1198	default:
[3232]	1199	printf(" !<%d>", icmp_code);
[821]	1200	++unreachable;
	1201	break;
	1202	}
	1203	break;
[3232]	1204	} /* while (wait and read a packet) */
	1205
[2725]	1206	/* there was no packet at all? */
	1207	if (read_len == 0)
	1208	printf(" *");
[3232]	1209	} /* for (nprobes) */
	1210
[2725]	1211	bb_putchar('\n');
	1212	if (got_there
	1213	\|\| (unreachable > 0 && unreachable >= nprobes - 1)
	1214	) {
[821]	1215	break;
[2725]	1216	}
[821]	1217	}
[2725]	1218
[821]	1219	return 0;
	1220	}
[2725]	1221
	1222	int traceroute_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
	1223	int traceroute_main(int argc UNUSED_PARAM, char **argv)
	1224	{
	1225	return common_traceroute_main(0, argv);
	1226	}
	1227
	1228	#if ENABLE_TRACEROUTE6
	1229	int traceroute6_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
	1230	int traceroute6_main(int argc UNUSED_PARAM, char **argv)
	1231	{
	1232	return common_traceroute_main(OPT_IPV6, argv);
	1233	}
	1234	#endif

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source: MondoRescue/branches/3.2/mindi-busybox/networking/traceroute.c

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