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1/* vi: set sw=4 ts=4: */
2/*
3 * Mini ping implementation for busybox
4 *
5 * Copyright (C) 1999 by Randolph Chung <tausq@debian.org>
6 *
7 * Adapted from the ping in netkit-base 0.10:
8 * Copyright (c) 1989 The Regents of the University of California.
9 * All rights reserved.
10 *
11 * This code is derived from software contributed to Berkeley by
12 * Mike Muuss.
13 *
14 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
15 */
16/* from ping6.c:
17 * Copyright (C) 1999 by Randolph Chung <tausq@debian.org>
18 *
19 * This version of ping is adapted from the ping in netkit-base 0.10,
20 * which is:
21 *
22 * Original copyright notice is retained at the end of this file.
23 *
24 * This version is an adaptation of ping.c from busybox.
25 * The code was modified by Bart Visscher <magick@linux-fan.com>
26 */
27
28#include <net/if.h>
29#include <netinet/ip_icmp.h>
30#include "libbb.h"
31
32#if ENABLE_PING6
33# include <netinet/icmp6.h>
34/* I see RENUMBERED constants in bits/in.h - !!?
35 * What a fuck is going on with libc? Is it a glibc joke? */
36# ifdef IPV6_2292HOPLIMIT
37#  undef IPV6_HOPLIMIT
38#  define IPV6_HOPLIMIT IPV6_2292HOPLIMIT
39# endif
40# if IPV6_PMTUDISC_DONT != IP_PMTUDISC_DONT || \
41     IPV6_PMTUDISC_WANT != IP_PMTUDISC_WANT || \
42     IPV6_PMTUDISC_DO != IP_PMTUDISC_DO
43#  error IPV6_PMTUDISC_* & IP_PMTUDISC_* constants mismatch
44# endif
45#endif
46
47enum {
48	DEFDATALEN = 56,
49	MAXIPLEN = 60,
50	MAXICMPLEN = 76,
51	MAX_DUP_CHK = (8 * 128),
52	MAXWAIT = 10,
53	PINGINTERVAL = 1, /* 1 second */
54};
55
56/* Common routines */
57
58static int in_cksum(unsigned short *buf, int sz)
59{
60	int nleft = sz;
61	int sum = 0;
62	unsigned short *w = buf;
63	unsigned short ans = 0;
64
65	while (nleft > 1) {
66		sum += *w++;
67		nleft -= 2;
68	}
69
70	if (nleft == 1) {
71		*(unsigned char *) (&ans) = *(unsigned char *) w;
72		sum += ans;
73	}
74
75	sum = (sum >> 16) + (sum & 0xFFFF);
76	sum += (sum >> 16);
77	ans = ~sum;
78	return ans;
79}
80
81#if !ENABLE_FEATURE_FANCY_PING
82
83/* Simple version */
84
85struct globals {
86	char *hostname;
87	char packet[DEFDATALEN + MAXIPLEN + MAXICMPLEN];
88} FIX_ALIASING;
89#define G (*(struct globals*)&bb_common_bufsiz1)
90#define INIT_G() do { } while (0)
91
92static void noresp(int ign UNUSED_PARAM)
93{
94	printf("No response from %s\n", G.hostname);
95	exit(EXIT_FAILURE);
96}
97
98static void ping4(len_and_sockaddr *lsa)
99{
100	struct icmp *pkt;
101	int pingsock, c;
102
103	pingsock = create_icmp_socket();
104
105	pkt = (struct icmp *) G.packet;
106	memset(pkt, 0, sizeof(G.packet));
107	pkt->icmp_type = ICMP_ECHO;
108	pkt->icmp_cksum = in_cksum((unsigned short *) pkt, sizeof(G.packet));
109
110	xsendto(pingsock, G.packet, DEFDATALEN + ICMP_MINLEN, &lsa->u.sa, lsa->len);
111
112	/* listen for replies */
113	while (1) {
114		struct sockaddr_in from;
115		socklen_t fromlen = sizeof(from);
116
117		c = recvfrom(pingsock, G.packet, sizeof(G.packet), 0,
118				(struct sockaddr *) &from, &fromlen);
119		if (c < 0) {
120			if (errno != EINTR)
121				bb_perror_msg("recvfrom");
122			continue;
123		}
124		if (c >= 76) {			/* ip + icmp */
125			struct iphdr *iphdr = (struct iphdr *) G.packet;
126
127			pkt = (struct icmp *) (G.packet + (iphdr->ihl << 2));	/* skip ip hdr */
128			if (pkt->icmp_type == ICMP_ECHOREPLY)
129				break;
130		}
131	}
132	if (ENABLE_FEATURE_CLEAN_UP)
133		close(pingsock);
134}
135
136#if ENABLE_PING6
137static void ping6(len_and_sockaddr *lsa)
138{
139	struct icmp6_hdr *pkt;
140	int pingsock, c;
141	int sockopt;
142
143	pingsock = create_icmp6_socket();
144
145	pkt = (struct icmp6_hdr *) G.packet;
146	memset(pkt, 0, sizeof(G.packet));
147	pkt->icmp6_type = ICMP6_ECHO_REQUEST;
148
149	sockopt = offsetof(struct icmp6_hdr, icmp6_cksum);
150	setsockopt(pingsock, SOL_RAW, IPV6_CHECKSUM, &sockopt, sizeof(sockopt));
151
152	xsendto(pingsock, G.packet, DEFDATALEN + sizeof(struct icmp6_hdr), &lsa->u.sa, lsa->len);
153
154	/* listen for replies */
155	while (1) {
156		struct sockaddr_in6 from;
157		socklen_t fromlen = sizeof(from);
158
159		c = recvfrom(pingsock, G.packet, sizeof(G.packet), 0,
160				(struct sockaddr *) &from, &fromlen);
161		if (c < 0) {
162			if (errno != EINTR)
163				bb_perror_msg("recvfrom");
164			continue;
165		}
166		if (c >= ICMP_MINLEN) {			/* icmp6_hdr */
167			pkt = (struct icmp6_hdr *) G.packet;
168			if (pkt->icmp6_type == ICMP6_ECHO_REPLY)
169				break;
170		}
171	}
172	if (ENABLE_FEATURE_CLEAN_UP)
173		close(pingsock);
174}
175#endif
176
177#if !ENABLE_PING6
178# define common_ping_main(af, argv) common_ping_main(argv)
179#endif
180static int common_ping_main(sa_family_t af, char **argv)
181{
182	len_and_sockaddr *lsa;
183
184	INIT_G();
185
186#if ENABLE_PING6
187	while ((++argv)[0] && argv[0][0] == '-') {
188		if (argv[0][1] == '4') {
189			af = AF_INET;
190			continue;
191		}
192		if (argv[0][1] == '6') {
193			af = AF_INET6;
194			continue;
195		}
196		bb_show_usage();
197	}
198#else
199	argv++;
200#endif
201
202	G.hostname = *argv;
203	if (!G.hostname)
204		bb_show_usage();
205
206#if ENABLE_PING6
207	lsa = xhost_and_af2sockaddr(G.hostname, 0, af);
208#else
209	lsa = xhost_and_af2sockaddr(G.hostname, 0, AF_INET);
210#endif
211	/* Set timer _after_ DNS resolution */
212	signal(SIGALRM, noresp);
213	alarm(5); /* give the host 5000ms to respond */
214
215#if ENABLE_PING6
216	if (lsa->u.sa.sa_family == AF_INET6)
217		ping6(lsa);
218	else
219#endif
220		ping4(lsa);
221	printf("%s is alive!\n", G.hostname);
222	return EXIT_SUCCESS;
223}
224
225
226#else /* FEATURE_FANCY_PING */
227
228
229/* Full(er) version */
230
231#define OPT_STRING ("qvc:s:t:w:W:I:M:4" IF_PING6("6"))
232enum {
233	OPT_QUIET = 1 << 0,
234	OPT_VERBOSE = 1 << 1,
235	OPT_c = 1 << 2,
236	OPT_s = 1 << 3,
237	OPT_t = 1 << 4,
238	OPT_w = 1 << 5,
239	OPT_W = 1 << 6,
240	OPT_I = 1 << 7,
241	OPT_M = 1 << 8,
242	OPT_IPV4 = 1 << 9,
243	OPT_IPV6 = (1 << 10) * ENABLE_PING6,
244};
245
246
247struct globals {
248	int pingsock;
249	int if_index;
250	char *str_I;
251	len_and_sockaddr *source_lsa;
252	unsigned datalen;
253	unsigned pingcount; /* must be int-sized */
254	unsigned opt_ttl;
255	int pmtudisc;
256	unsigned long ntransmitted, nreceived, nrepeats;
257	uint16_t myid;
258	unsigned tmin, tmax; /* in us */
259	unsigned long long tsum; /* in us, sum of all times */
260	unsigned deadline;
261	unsigned timeout;
262	unsigned total_secs;
263	unsigned sizeof_rcv_packet;
264	char *rcv_packet; /* [datalen + MAXIPLEN + MAXICMPLEN] */
265	void *snd_packet; /* [datalen + ipv4/ipv6_const] */
266	const char *hostname;
267	const char *dotted;
268	union {
269		struct sockaddr sa;
270		struct sockaddr_in sin;
271#if ENABLE_PING6
272		struct sockaddr_in6 sin6;
273#endif
274	} pingaddr;
275	char rcvd_tbl[MAX_DUP_CHK / 8];
276} FIX_ALIASING;
277#define G (*(struct globals*)&bb_common_bufsiz1)
278#define pingsock     (G.pingsock    )
279#define if_index     (G.if_index    )
280#define source_lsa   (G.source_lsa  )
281#define str_I        (G.str_I       )
282#define datalen      (G.datalen     )
283#define ntransmitted (G.ntransmitted)
284#define nreceived    (G.nreceived   )
285#define nrepeats     (G.nrepeats    )
286#define pingcount    (G.pingcount   )
287#define opt_ttl      (G.opt_ttl     )
288#define pmtudisc     (G.pmtudisc    )
289#define myid         (G.myid        )
290#define tmin         (G.tmin        )
291#define tmax         (G.tmax        )
292#define tsum         (G.tsum        )
293#define deadline     (G.deadline    )
294#define timeout      (G.timeout     )
295#define total_secs   (G.total_secs  )
296#define hostname     (G.hostname    )
297#define dotted       (G.dotted      )
298#define pingaddr     (G.pingaddr    )
299#define rcvd_tbl     (G.rcvd_tbl    )
300void BUG_ping_globals_too_big(void);
301#define INIT_G() do { \
302	if (sizeof(G) > COMMON_BUFSIZE) \
303		BUG_ping_globals_too_big(); \
304	pingsock = -1; \
305	datalen = DEFDATALEN; \
306	timeout = MAXWAIT; \
307	tmin = UINT_MAX; \
308	pmtudisc = -1; \
309} while (0)
310
311
312#define	A(bit)		rcvd_tbl[(bit)>>3]	/* identify byte in array */
313#define	B(bit)		(1 << ((bit) & 0x07))	/* identify bit in byte */
314#define	SET(bit)	(A(bit) |= B(bit))
315#define	CLR(bit)	(A(bit) &= (~B(bit)))
316#define	TST(bit)	(A(bit) & B(bit))
317
318/**************************************************************************/
319
320static void print_stats_and_exit(int junk) NORETURN;
321static void print_stats_and_exit(int junk UNUSED_PARAM)
322{
323	signal(SIGINT, SIG_IGN);
324
325	printf("\n--- %s ping statistics ---\n", hostname);
326	printf("%lu packets transmitted, ", ntransmitted);
327	printf("%lu packets received, ", nreceived);
328	if (nrepeats)
329		printf("%lu duplicates, ", nrepeats);
330	if (ntransmitted)
331		ntransmitted = (ntransmitted - nreceived) * 100 / ntransmitted;
332	printf("%lu%% packet loss\n", ntransmitted);
333	if (tmin != UINT_MAX) {
334		unsigned tavg = tsum / (nreceived + nrepeats);
335		printf("round-trip min/avg/max = %u.%03u/%u.%03u/%u.%03u ms\n",
336			tmin / 1000, tmin % 1000,
337			tavg / 1000, tavg % 1000,
338			tmax / 1000, tmax % 1000);
339	}
340	/* if condition is true, exit with 1 -- 'failure' */
341	exit(nreceived == 0 || (deadline && nreceived < pingcount));
342}
343
344static void sendping_tail(void (*sp)(int), const void *pkt, int size_pkt)
345{
346	int sz;
347
348	CLR((uint16_t)ntransmitted % MAX_DUP_CHK);
349	ntransmitted++;
350
351	/* sizeof(pingaddr) can be larger than real sa size, but I think
352	 * it doesn't matter */
353	sz = xsendto(pingsock, pkt, size_pkt, &pingaddr.sa, sizeof(pingaddr));
354	if (sz != size_pkt)
355		bb_error_msg_and_die(bb_msg_write_error);
356
357	if (pingcount == 0 || deadline || ntransmitted < pingcount) {
358		/* Didn't send all pings yet - schedule next in 1s */
359		signal(SIGALRM, sp);
360		if (deadline) {
361			total_secs += PINGINTERVAL;
362			if (total_secs >= deadline)
363				signal(SIGALRM, print_stats_and_exit);
364		}
365		alarm(PINGINTERVAL);
366	} else { /* -c NN, and all NN are sent (and no deadline) */
367		/* Wait for the last ping to come back.
368		 * -W timeout: wait for a response in seconds.
369		 * Affects only timeout in absense of any responses,
370		 * otherwise ping waits for two RTTs. */
371		unsigned expire = timeout;
372
373		if (nreceived) {
374			/* approx. 2*tmax, in seconds (2 RTT) */
375			expire = tmax / (512*1024);
376			if (expire == 0)
377				expire = 1;
378		}
379		signal(SIGALRM, print_stats_and_exit);
380		alarm(expire);
381	}
382}
383
384static void sendping4(int junk UNUSED_PARAM)
385{
386	struct icmp *pkt = G.snd_packet;
387
388	//memset(pkt, 0, datalen + ICMP_MINLEN + 4); - G.snd_packet was xzalloced
389	pkt->icmp_type = ICMP_ECHO;
390	/*pkt->icmp_code = 0;*/
391	pkt->icmp_cksum = 0; /* cksum is calculated with this field set to 0 */
392	pkt->icmp_seq = htons(ntransmitted); /* don't ++ here, it can be a macro */
393	pkt->icmp_id = myid;
394
395	/* If datalen < 4, we store timestamp _past_ the packet,
396	 * but it's ok - we allocated 4 extra bytes in xzalloc() just in case.
397	 */
398	/*if (datalen >= 4)*/
399		/* No hton: we'll read it back on the same machine */
400		*(uint32_t*)&pkt->icmp_dun = monotonic_us();
401
402	pkt->icmp_cksum = in_cksum((unsigned short *) pkt, datalen + ICMP_MINLEN);
403
404	sendping_tail(sendping4, pkt, datalen + ICMP_MINLEN);
405}
406#if ENABLE_PING6
407static void sendping6(int junk UNUSED_PARAM)
408{
409	struct icmp6_hdr *pkt = alloca(datalen + sizeof(struct icmp6_hdr) + 4);
410
411	//memset(pkt, 0, datalen + sizeof(struct icmp6_hdr) + 4);
412	pkt->icmp6_type = ICMP6_ECHO_REQUEST;
413	/*pkt->icmp6_code = 0;*/
414	/*pkt->icmp6_cksum = 0;*/
415	pkt->icmp6_seq = htons(ntransmitted); /* don't ++ here, it can be a macro */
416	pkt->icmp6_id = myid;
417
418	/*if (datalen >= 4)*/
419		*(uint32_t*)(&pkt->icmp6_data8[4]) = monotonic_us();
420
421	//TODO? pkt->icmp_cksum = in_cksum(...);
422
423	sendping_tail(sendping6, pkt, datalen + sizeof(struct icmp6_hdr));
424}
425#endif
426
427static const char *icmp_type_name(int id)
428{
429	switch (id) {
430	case ICMP_ECHOREPLY:      return "Echo Reply";
431	case ICMP_DEST_UNREACH:   return "Destination Unreachable";
432	case ICMP_SOURCE_QUENCH:  return "Source Quench";
433	case ICMP_REDIRECT:       return "Redirect (change route)";
434	case ICMP_ECHO:           return "Echo Request";
435	case ICMP_TIME_EXCEEDED:  return "Time Exceeded";
436	case ICMP_PARAMETERPROB:  return "Parameter Problem";
437	case ICMP_TIMESTAMP:      return "Timestamp Request";
438	case ICMP_TIMESTAMPREPLY: return "Timestamp Reply";
439	case ICMP_INFO_REQUEST:   return "Information Request";
440	case ICMP_INFO_REPLY:     return "Information Reply";
441	case ICMP_ADDRESS:        return "Address Mask Request";
442	case ICMP_ADDRESSREPLY:   return "Address Mask Reply";
443	default:                  return "unknown ICMP type";
444	}
445}
446#if ENABLE_PING6
447/* RFC3542 changed some definitions from RFC2292 for no good reason, whee!
448 * the newer 3542 uses a MLD_ prefix where as 2292 uses ICMP6_ prefix */
449#ifndef MLD_LISTENER_QUERY
450# define MLD_LISTENER_QUERY ICMP6_MEMBERSHIP_QUERY
451#endif
452#ifndef MLD_LISTENER_REPORT
453# define MLD_LISTENER_REPORT ICMP6_MEMBERSHIP_REPORT
454#endif
455#ifndef MLD_LISTENER_REDUCTION
456# define MLD_LISTENER_REDUCTION ICMP6_MEMBERSHIP_REDUCTION
457#endif
458static const char *icmp6_type_name(int id)
459{
460	switch (id) {
461	case ICMP6_DST_UNREACH:      return "Destination Unreachable";
462	case ICMP6_PACKET_TOO_BIG:   return "Packet too big";
463	case ICMP6_TIME_EXCEEDED:    return "Time Exceeded";
464	case ICMP6_PARAM_PROB:       return "Parameter Problem";
465	case ICMP6_ECHO_REPLY:       return "Echo Reply";
466	case ICMP6_ECHO_REQUEST:     return "Echo Request";
467	case MLD_LISTENER_QUERY:     return "Listener Query";
468	case MLD_LISTENER_REPORT:    return "Listener Report";
469	case MLD_LISTENER_REDUCTION: return "Listener Reduction";
470	default:                     return "unknown ICMP type";
471	}
472}
473#endif
474
475static void unpack_tail(int sz, uint32_t *tp,
476		const char *from_str,
477		uint16_t recv_seq, int ttl)
478{
479	const char *dupmsg = " (DUP!)";
480	unsigned triptime = triptime; /* for gcc */
481
482	++nreceived;
483
484	if (tp) {
485		/* (int32_t) cast is for hypothetical 64-bit unsigned */
486		/* (doesn't hurt 32-bit real-world anyway) */
487		triptime = (int32_t) ((uint32_t)monotonic_us() - *tp);
488		tsum += triptime;
489		if (triptime < tmin)
490			tmin = triptime;
491		if (triptime > tmax)
492			tmax = triptime;
493	}
494
495	if (TST(recv_seq % MAX_DUP_CHK)) {
496		++nrepeats;
497		--nreceived;
498	} else {
499		SET(recv_seq % MAX_DUP_CHK);
500		dupmsg += 7;
501	}
502
503	if (option_mask32 & OPT_QUIET)
504		return;
505
506	printf("%d bytes from %s: seq=%u ttl=%d", sz,
507		from_str, recv_seq, ttl);
508	if (tp)
509		printf(" time=%u.%03u ms", triptime / 1000, triptime % 1000);
510	puts(dupmsg);
511	fflush_all();
512}
513static void unpack4(char *buf, int sz, struct sockaddr_in *from)
514{
515	struct icmp *icmppkt;
516	struct iphdr *iphdr;
517	int hlen;
518
519	/* discard if too short */
520	if (sz < (datalen + ICMP_MINLEN))
521		return;
522
523	/* check IP header */
524	iphdr = (struct iphdr *) buf;
525	hlen = iphdr->ihl << 2;
526	sz -= hlen;
527	icmppkt = (struct icmp *) (buf + hlen);
528	if (icmppkt->icmp_id != myid)
529		return;				/* not our ping */
530
531	if (icmppkt->icmp_type == ICMP_ECHOREPLY) {
532		uint16_t recv_seq = ntohs(icmppkt->icmp_seq);
533		uint32_t *tp = NULL;
534
535		if (sz >= ICMP_MINLEN + sizeof(uint32_t))
536			tp = (uint32_t *) icmppkt->icmp_data;
537		unpack_tail(sz, tp,
538			inet_ntoa(*(struct in_addr *) &from->sin_addr.s_addr),
539			recv_seq, iphdr->ttl);
540	} else if (icmppkt->icmp_type != ICMP_ECHO) {
541		bb_error_msg("warning: got ICMP %d (%s)",
542				icmppkt->icmp_type,
543				icmp_type_name(icmppkt->icmp_type));
544	}
545}
546#if ENABLE_PING6
547static void unpack6(char *packet, int sz, /*struct sockaddr_in6 *from,*/ int hoplimit)
548{
549	struct icmp6_hdr *icmppkt;
550	char buf[INET6_ADDRSTRLEN];
551
552	/* discard if too short */
553	if (sz < (datalen + sizeof(struct icmp6_hdr)))
554		return;
555
556	icmppkt = (struct icmp6_hdr *) packet;
557	if (icmppkt->icmp6_id != myid)
558		return;				/* not our ping */
559
560	if (icmppkt->icmp6_type == ICMP6_ECHO_REPLY) {
561		uint16_t recv_seq = ntohs(icmppkt->icmp6_seq);
562		uint32_t *tp = NULL;
563
564		if (sz >= sizeof(struct icmp6_hdr) + sizeof(uint32_t))
565			tp = (uint32_t *) &icmppkt->icmp6_data8[4];
566		unpack_tail(sz, tp,
567			inet_ntop(AF_INET6, &pingaddr.sin6.sin6_addr,
568					buf, sizeof(buf)),
569			recv_seq, hoplimit);
570	} else if (icmppkt->icmp6_type != ICMP6_ECHO_REQUEST) {
571		bb_error_msg("warning: got ICMP %d (%s)",
572				icmppkt->icmp6_type,
573				icmp6_type_name(icmppkt->icmp6_type));
574	}
575}
576#endif
577
578static void ping4(len_and_sockaddr *lsa)
579{
580	int sockopt;
581
582	pingsock = create_icmp_socket();
583	pingaddr.sin = lsa->u.sin;
584	if (source_lsa) {
585		if (setsockopt(pingsock, IPPROTO_IP, IP_MULTICAST_IF,
586				&source_lsa->u.sa, source_lsa->len))
587			bb_error_msg_and_die("can't set multicast source interface");
588		xbind(pingsock, &source_lsa->u.sa, source_lsa->len);
589	}
590	if (str_I)
591		setsockopt_bindtodevice(pingsock, str_I);
592
593	/* enable broadcast pings */
594	setsockopt_broadcast(pingsock);
595
596	/* set recv buf (needed if we can get lots of responses: flood ping,
597	 * broadcast ping etc) */
598	sockopt = (datalen * 2) + 7 * 1024; /* giving it a bit of extra room */
599	setsockopt(pingsock, SOL_SOCKET, SO_RCVBUF, &sockopt, sizeof(sockopt));
600
601	if (opt_ttl != 0) {
602		setsockopt(pingsock, IPPROTO_IP, IP_TTL, &opt_ttl, sizeof(opt_ttl));
603		/* above doesnt affect packets sent to bcast IP, so... */
604		setsockopt(pingsock, IPPROTO_IP, IP_MULTICAST_TTL, &opt_ttl, sizeof(opt_ttl));
605	}
606
607	if (IN_MULTICAST(ntohl(pingaddr.sin.sin_addr.s_addr))) {
608		if (myid && pmtudisc >= 0 && pmtudisc != IPV6_PMTUDISC_DO)
609			bb_error_msg_and_die("multicast ping does not fragment");
610		if (pmtudisc < 0)
611			pmtudisc = IPV6_PMTUDISC_DO;
612	}
613	if (pmtudisc >= 0)
614		setsockopt(pingsock, SOL_IP, IP_MTU_DISCOVER, &pmtudisc, sizeof(pmtudisc));
615
616	signal(SIGINT, print_stats_and_exit);
617
618	/* start the ping's going ... */
619	sendping4(0);
620
621	/* listen for replies */
622	while (1) {
623		struct sockaddr_in from;
624		socklen_t fromlen = (socklen_t) sizeof(from);
625		int c;
626
627		c = recvfrom(pingsock, G.rcv_packet, G.sizeof_rcv_packet, 0,
628				(struct sockaddr *) &from, &fromlen);
629		if (c < 0) {
630			if (errno != EINTR)
631				bb_perror_msg("recvfrom");
632			continue;
633		}
634		unpack4(G.rcv_packet, c, &from);
635		if (pingcount && nreceived >= pingcount)
636			break;
637	}
638}
639#if ENABLE_PING6
640extern int BUG_bad_offsetof_icmp6_cksum(void);
641static void ping6(len_and_sockaddr *lsa)
642{
643	int sockopt;
644	struct msghdr msg;
645	struct sockaddr_in6 from;
646	struct iovec iov;
647	char control_buf[CMSG_SPACE(36)];
648
649	pingsock = create_icmp6_socket();
650	pingaddr.sin6 = lsa->u.sin6;
651	/* untested whether "-I addr" really works for IPv6: */
652	if (source_lsa)
653		xbind(pingsock, &source_lsa->u.sa, source_lsa->len);
654	if (str_I)
655		setsockopt_bindtodevice(pingsock, str_I);
656
657#ifdef ICMP6_FILTER
658	{
659		struct icmp6_filter filt;
660		if (!(option_mask32 & OPT_VERBOSE)) {
661			ICMP6_FILTER_SETBLOCKALL(&filt);
662			ICMP6_FILTER_SETPASS(ICMP6_ECHO_REPLY, &filt);
663		} else {
664			ICMP6_FILTER_SETPASSALL(&filt);
665		}
666		if (setsockopt(pingsock, IPPROTO_ICMPV6, ICMP6_FILTER, &filt,
667					   sizeof(filt)) < 0)
668			bb_error_msg_and_die("setsockopt(ICMP6_FILTER)");
669	}
670#endif /*ICMP6_FILTER*/
671
672	/* enable broadcast pings */
673	setsockopt_broadcast(pingsock);
674
675	/* set recv buf (needed if we can get lots of responses: flood ping,
676	 * broadcast ping etc) */
677	sockopt = (datalen * 2) + 7 * 1024; /* giving it a bit of extra room */
678	setsockopt(pingsock, SOL_SOCKET, SO_RCVBUF, &sockopt, sizeof(sockopt));
679
680	sockopt = offsetof(struct icmp6_hdr, icmp6_cksum);
681	if (offsetof(struct icmp6_hdr, icmp6_cksum) != 2)
682		BUG_bad_offsetof_icmp6_cksum();
683	setsockopt(pingsock, SOL_RAW, IPV6_CHECKSUM, &sockopt, sizeof(sockopt));
684
685	if (opt_ttl != 0) {
686		setsockopt(pingsock, IPPROTO_IPV6, IPV6_UNICAST_HOPS, &opt_ttl, sizeof(opt_ttl));
687		setsockopt(pingsock, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &opt_ttl, sizeof(opt_ttl));
688	}
689
690	/* request ttl info to be returned in ancillary data */
691	setsockopt(pingsock, SOL_IPV6, IPV6_HOPLIMIT, &const_int_1, sizeof(const_int_1));
692
693	if (if_index)
694		pingaddr.sin6.sin6_scope_id = if_index;
695
696	if ((pingaddr.sin6.sin6_addr.s6_addr16[0] & htons(0xff00)) == htons(0xff00)) {
697		if (myid && pmtudisc >= 0 && pmtudisc != IPV6_PMTUDISC_DO)
698			bb_error_msg_and_die("multicast ping does not fragment");
699		if (pmtudisc < 0)
700			pmtudisc = IPV6_PMTUDISC_DO;
701	}
702	if (pmtudisc >= 0)
703		setsockopt(pingsock, SOL_IPV6, IPV6_MTU_DISCOVER, &pmtudisc, sizeof(pmtudisc));
704
705	signal(SIGINT, print_stats_and_exit);
706
707	/* start the ping's going ... */
708	sendping6(0);
709
710	/* listen for replies */
711	msg.msg_name = &from;
712	msg.msg_namelen = sizeof(from);
713	msg.msg_iov = &iov;
714	msg.msg_iovlen = 1;
715	msg.msg_control = control_buf;
716	iov.iov_base = G.rcv_packet;
717	iov.iov_len = G.sizeof_rcv_packet;
718	while (1) {
719		int c;
720		struct cmsghdr *mp;
721		int hoplimit = -1;
722		msg.msg_controllen = sizeof(control_buf);
723
724		c = recvmsg(pingsock, &msg, 0);
725		if (c < 0) {
726			if (errno != EINTR)
727				bb_perror_msg("recvfrom");
728			continue;
729		}
730		for (mp = CMSG_FIRSTHDR(&msg); mp; mp = CMSG_NXTHDR(&msg, mp)) {
731			if (mp->cmsg_level == SOL_IPV6
732			 && mp->cmsg_type == IPV6_HOPLIMIT
733			 /* don't check len - we trust the kernel: */
734			 /* && mp->cmsg_len >= CMSG_LEN(sizeof(int)) */
735			) {
736				/*hoplimit = *(int*)CMSG_DATA(mp); - unaligned access */
737				move_from_unaligned_int(hoplimit, CMSG_DATA(mp));
738			}
739		}
740		unpack6(G.rcv_packet, c, /*&from,*/ hoplimit);
741		if (pingcount && nreceived >= pingcount)
742			break;
743	}
744}
745#endif
746
747static void ping(len_and_sockaddr *lsa)
748{
749	printf("PING %s (%s)", hostname, dotted);
750	if (source_lsa) {
751		printf(" from %s",
752			xmalloc_sockaddr2dotted_noport(&source_lsa->u.sa));
753	}
754	printf(": %d data bytes\n", datalen);
755
756	G.sizeof_rcv_packet = datalen + MAXIPLEN + MAXICMPLEN;
757	G.rcv_packet = xzalloc(G.sizeof_rcv_packet);
758#if ENABLE_PING6
759	if (lsa->u.sa.sa_family == AF_INET6) {
760		/* +4 reserves a place for timestamp, which may end up sitting
761		 * _after_ packet. Saves one if() - see sendping4/6() */
762		G.snd_packet = xzalloc(datalen + sizeof(struct icmp6_hdr) + 4);
763		ping6(lsa);
764	} else
765#endif
766	{
767		G.snd_packet = xzalloc(datalen + ICMP_MINLEN + 4);
768		ping4(lsa);
769	}
770}
771
772static int common_ping_main(int opt, char **argv)
773{
774	len_and_sockaddr *lsa;
775	char *str_s, *str_M;
776
777	INIT_G();
778
779	/* exactly one argument needed; -v and -q don't mix; -c NUM, -t NUM, -w NUM, -W NUM */
780	opt_complementary = "=1:q--v:v--q:c+:t+:w+:W+";
781	opt |= getopt32(argv, OPT_STRING, &pingcount, &str_s, &opt_ttl, &deadline, &timeout, &str_I, &str_M);
782	if (opt & OPT_s)
783		datalen = xatou16(str_s); // -s
784	if (opt & OPT_I) { // -I
785		if_index = if_nametoindex(str_I);
786		if (!if_index) {
787			/* TODO: I'm not sure it takes IPv6 unless in [XX:XX..] format */
788			source_lsa = xdotted2sockaddr(str_I, 0);
789			str_I = NULL; /* don't try to bind to device later */
790		}
791	}
792	myid = (uint16_t) getpid();
793	hostname = argv[optind];
794#if ENABLE_PING6
795	{
796		sa_family_t af = AF_UNSPEC;
797		if (opt & OPT_IPV4)
798			af = AF_INET;
799		if (opt & OPT_IPV6)
800			af = AF_INET6;
801		lsa = xhost_and_af2sockaddr(hostname, 0, af);
802	}
803#else
804	lsa = xhost_and_af2sockaddr(hostname, 0, AF_INET);
805#endif
806	if (opt & OPT_M) { // -M
807		if (strcmp(str_M, "do") == 0)
808			pmtudisc = IP_PMTUDISC_DO;
809		else if (strcmp(str_M, "dont") == 0)
810			pmtudisc = IP_PMTUDISC_DONT;
811		else if (strcmp(str_M, "want") == 0)
812			pmtudisc = IP_PMTUDISC_WANT;
813	}
814
815	if (source_lsa && source_lsa->u.sa.sa_family != lsa->u.sa.sa_family)
816		/* leaking it here... */
817		source_lsa = NULL;
818
819	dotted = xmalloc_sockaddr2dotted_noport(&lsa->u.sa);
820	ping(lsa);
821	print_stats_and_exit(EXIT_SUCCESS);
822	/*return EXIT_SUCCESS;*/
823}
824#endif /* FEATURE_FANCY_PING */
825
826
827int ping_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
828int ping_main(int argc UNUSED_PARAM, char **argv)
829{
830#if !ENABLE_FEATURE_FANCY_PING
831	return common_ping_main(AF_UNSPEC, argv);
832#else
833	return common_ping_main(0, argv);
834#endif
835}
836
837#if ENABLE_PING6
838int ping6_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
839int ping6_main(int argc UNUSED_PARAM, char **argv)
840{
841# if !ENABLE_FEATURE_FANCY_PING
842	return common_ping_main(AF_INET6, argv);
843# else
844	return common_ping_main(OPT_IPV6, argv);
845# endif
846}
847#endif
848
849/* from ping6.c:
850 * Copyright (c) 1989 The Regents of the University of California.
851 * All rights reserved.
852 *
853 * This code is derived from software contributed to Berkeley by
854 * Mike Muuss.
855 *
856 * Redistribution and use in source and binary forms, with or without
857 * modification, are permitted provided that the following conditions
858 * are met:
859 * 1. Redistributions of source code must retain the above copyright
860 *    notice, this list of conditions and the following disclaimer.
861 * 2. Redistributions in binary form must reproduce the above copyright
862 *    notice, this list of conditions and the following disclaimer in the
863 *    documentation and/or other materials provided with the distribution.
864 *
865 * 3. <BSD Advertising Clause omitted per the July 22, 1999 licensing change
866 *		ftp://ftp.cs.berkeley.edu/pub/4bsd/README.Impt.License.Change>
867 *
868 * 4. Neither the name of the University nor the names of its contributors
869 *    may be used to endorse or promote products derived from this software
870 *    without specific prior written permission.
871 *
872 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
873 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
874 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
875 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
876 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
877 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
878 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
879 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
880 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
881 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
882 * SUCH DAMAGE.
883 */
884