1 /*
2  * Copyright (c) 1989 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Mike Muuss.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #ifndef lint
38 char copyright[] =
39 "@(#) Copyright (c) 1989 The Regents of the University of California.\n\
40  All rights reserved.\n";
41 #endif /* not lint */
42 
43 /*
44  *			P I N G . C
45  *
46  * Using the InterNet Control Message Protocol (ICMP) "ECHO" facility,
47  * measure round-trip-delays and packet loss across network paths.
48  *
49  * Author -
50  *	Mike Muuss
51  *	U. S. Army Ballistic Research Laboratory
52  *	December, 1983
53  *
54  * Status -
55  *	Public Domain.  Distribution Unlimited.
56  * Bugs -
57  *	More statistics could always be gathered.
58  *	This program has to run SUID to ROOT to access the ICMP socket.
59  */
60 
61 #include "ping_common.h"
62 
63 #include <netinet/ip.h>
64 #include <netinet/ip_icmp.h>
65 #ifndef WITHOUT_IFADDRS
66 #include <ifaddrs.h>
67 #endif
68 
69 #ifndef ICMP_FILTER
70 #define ICMP_FILTER	1
71 struct icmp_filter {
72 	__u32	data;
73 };
74 #endif
75 
76 #define	MAXIPLEN	60
77 #define	MAXICMPLEN	76
78 #define	NROUTES		9		/* number of record route slots */
79 #define TOS_MAX		255		/* 8-bit TOS field */
80 #define MAX_HOSTNAMELEN	NI_MAXHOST
81 
82 
83 static int ts_type;
84 static int nroute = 0;
85 static __u32 route[10];
86 
87 
88 
89 struct sockaddr_in whereto;	/* who to ping */
90 int optlen = 0;
91 int settos = 0;			/* Set TOS, Precendence or other QOS options */
92 int icmp_sock;			/* socket file descriptor */
93 u_char outpack[0x10000];
94 int maxpacket = sizeof(outpack);
95 
96 static int broadcast_pings = 0;
97 
98 static char *pr_addr(__u32);
99 static void pr_options(unsigned char * cp, int hlen);
100 static void pr_iph(struct iphdr *ip);
101 static void usage(void) __attribute__((noreturn));
102 static u_short in_cksum(const u_short *addr, int len, u_short salt);
103 static void pr_icmph(__u8 type, __u8 code, __u32 info, struct icmphdr *icp);
104 static int parsetos(char *str);
105 
106 static struct {
107 	struct cmsghdr cm;
108 	struct in_pktinfo ipi;
109 } cmsg = { {sizeof(struct cmsghdr) + sizeof(struct in_pktinfo), SOL_IP, IP_PKTINFO},
110 	   {0, }};
111 int cmsg_len;
112 
113 struct sockaddr_in source;
114 char *device;
115 int pmtudisc = -1;
116 
117 
118 int
main(int argc,char ** argv)119 main(int argc, char **argv)
120 {
121 	struct hostent *hp;
122 	int ch, hold, packlen;
123 	int socket_errno = 0;
124 	u_char *packet;
125 	char *target;
126 #ifdef USE_IDN
127 	char *hnamebuf = NULL;
128 #else
129 	char hnamebuf[MAX_HOSTNAMELEN];
130 #endif
131 	char rspace[3 + 4 * NROUTES + 1];	/* record route space */
132 
133 #ifdef ANDROID
134 	android_check_security();
135 #endif
136 
137 	limit_capabilities();
138 
139 #ifdef USE_IDN
140 	setlocale(LC_ALL, "");
141 #endif
142 
143 	icmp_sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_ICMP);
144 	if (icmp_sock < 0) {
145 		enable_capability_raw();
146 		icmp_sock = socket(AF_INET, SOCK_RAW, IPPROTO_ICMP);
147 		socket_errno = errno;
148 		disable_capability_raw();
149 		using_ping_socket = 0;
150 	}
151 
152 	source.sin_family = AF_INET;
153 
154 	preload = 1;
155 	while ((ch = getopt(argc, argv, COMMON_OPTSTR "bRT:")) != EOF) {
156 		switch(ch) {
157 		case 'b':
158 			broadcast_pings = 1;
159 			break;
160 		case 'Q':
161 			settos = parsetos(optarg);
162 			if (settos &&
163 			    (setsockopt(icmp_sock, IPPROTO_IP, IP_TOS,
164 					(char *)&settos, sizeof(int)) < 0)) {
165 				perror("ping: error setting QOS sockopts");
166 				exit(2);
167 			}
168 			break;
169 		case 'R':
170 			if (options & F_TIMESTAMP) {
171 				fprintf(stderr, "Only one of -T or -R may be used\n");
172 				exit(2);
173 			}
174 			options |= F_RROUTE;
175 			break;
176 		case 'T':
177 			if (options & F_RROUTE) {
178 				fprintf(stderr, "Only one of -T or -R may be used\n");
179 				exit(2);
180 			}
181 			options |= F_TIMESTAMP;
182 			if (strcmp(optarg, "tsonly") == 0)
183 				ts_type = IPOPT_TS_TSONLY;
184 			else if (strcmp(optarg, "tsandaddr") == 0)
185 				ts_type = IPOPT_TS_TSANDADDR;
186 			else if (strcmp(optarg, "tsprespec") == 0)
187 				ts_type = IPOPT_TS_PRESPEC;
188 			else {
189 				fprintf(stderr, "Invalid timestamp type\n");
190 				exit(2);
191 			}
192 			break;
193 		case 'I':
194 		{
195 #if 0
196 			char dummy;
197 			int i1, i2, i3, i4;
198 
199 			if (sscanf(optarg, "%u.%u.%u.%u%c",
200 				   &i1, &i2, &i3, &i4, &dummy) == 4) {
201 				__u8 *ptr;
202 				ptr = (__u8*)&source.sin_addr;
203 				ptr[0] = i1;
204 				ptr[1] = i2;
205 				ptr[2] = i3;
206 				ptr[3] = i4;
207 				options |= F_STRICTSOURCE;
208 			} else {
209 				device = optarg;
210 			}
211 #else
212 			if (inet_pton(AF_INET, optarg, &source.sin_addr) > 0)
213 				options |= F_STRICTSOURCE;
214 			else
215 				device = optarg;
216 #endif
217 			break;
218 		}
219 		case 'M':
220 			if (strcmp(optarg, "do") == 0)
221 				pmtudisc = IP_PMTUDISC_DO;
222 			else if (strcmp(optarg, "dont") == 0)
223 				pmtudisc = IP_PMTUDISC_DONT;
224 			else if (strcmp(optarg, "want") == 0)
225 				pmtudisc = IP_PMTUDISC_WANT;
226 			else {
227 				fprintf(stderr, "ping: wrong value for -M: do, dont, want are valid ones.\n");
228 				exit(2);
229 			}
230 			break;
231 		case 'V':
232 			printf("ping utility, iputils-%s\n", SNAPSHOT);
233 			exit(0);
234 		COMMON_OPTIONS
235 			common_options(ch);
236 			break;
237 		default:
238 			usage();
239 		}
240 	}
241 	argc -= optind;
242 	argv += optind;
243 
244 	if (argc == 0)
245 		usage();
246 	if (argc > 1) {
247 		if (options & F_RROUTE)
248 			usage();
249 		else if (options & F_TIMESTAMP) {
250 			if (ts_type != IPOPT_TS_PRESPEC)
251 				usage();
252 			if (argc > 5)
253 				usage();
254 		} else {
255 			if (argc > 10)
256 				usage();
257 			options |= F_SOURCEROUTE;
258 		}
259 	}
260 	while (argc > 0) {
261 		target = *argv;
262 
263 		memset((char *)&whereto, 0, sizeof(whereto));
264 		whereto.sin_family = AF_INET;
265 		if (inet_aton(target, &whereto.sin_addr) == 1) {
266 			hostname = target;
267 			if (argc == 1)
268 				options |= F_NUMERIC;
269 		} else {
270 			char *idn;
271 #ifdef USE_IDN
272 			int rc;
273 
274 			if (hnamebuf) {
275 				free(hnamebuf);
276 				hnamebuf = NULL;
277 			}
278 
279 			rc = idna_to_ascii_lz(target, &idn, 0);
280 			if (rc != IDNA_SUCCESS) {
281 				fprintf(stderr, "ping: IDN encoding failed: %s\n", idna_strerror(rc));
282 				exit(2);
283 			}
284 #else
285 			idn = target;
286 #endif
287 			hp = gethostbyname(idn);
288 			if (!hp) {
289 				fprintf(stderr, "ping: unknown host %s\n", target);
290 				exit(2);
291 			}
292 #ifdef USE_IDN
293 			free(idn);
294 #endif
295 			memcpy(&whereto.sin_addr, hp->h_addr, 4);
296 #ifdef USE_IDN
297 			if (idna_to_unicode_lzlz(hp->h_name, &hnamebuf, 0) != IDNA_SUCCESS) {
298 				hnamebuf = strdup(hp->h_name);
299 				if (!hnamebuf) {
300 					perror("ping: strdup");
301 					exit(-1);
302 				}
303 			}
304 #else
305 			strncpy(hnamebuf, hp->h_name, sizeof(hnamebuf) - 1);
306 			hnamebuf[sizeof(hnamebuf) - 1] = 0;
307 #endif
308 			hostname = hnamebuf;
309 		}
310 		if (argc > 1)
311 			route[nroute++] = whereto.sin_addr.s_addr;
312 		argc--;
313 		argv++;
314 	}
315 
316 	if (source.sin_addr.s_addr == 0) {
317 		socklen_t alen;
318 		struct sockaddr_in dst = whereto;
319 		int probe_fd = socket(AF_INET, SOCK_DGRAM, 0);
320 
321 		if (probe_fd < 0) {
322 			perror("socket");
323 			exit(2);
324 		}
325 		if (device) {
326 			struct ifreq ifr;
327 			int rc;
328 
329 			memset(&ifr, 0, sizeof(ifr));
330 			strncpy(ifr.ifr_name, device, IFNAMSIZ-1);
331 
332 			enable_capability_raw();
333 			rc = setsockopt(probe_fd, SOL_SOCKET, SO_BINDTODEVICE, device, strlen(device)+1);
334 			disable_capability_raw();
335 
336 			if (rc == -1) {
337 				if (IN_MULTICAST(ntohl(dst.sin_addr.s_addr))) {
338 					struct ip_mreqn imr;
339 					if (ioctl(probe_fd, SIOCGIFINDEX, &ifr) < 0) {
340 						fprintf(stderr, "ping: unknown iface %s\n", device);
341 						exit(2);
342 					}
343 					memset(&imr, 0, sizeof(imr));
344 					imr.imr_ifindex = ifr.ifr_ifindex;
345 					if (setsockopt(probe_fd, SOL_IP, IP_MULTICAST_IF, &imr, sizeof(imr)) == -1) {
346 						perror("ping: IP_MULTICAST_IF");
347 						exit(2);
348 					}
349 				} else {
350 					perror("ping: SO_BINDTODEVICE");
351 					exit(2);
352 				}
353 			}
354 		}
355 
356 		if (settos &&
357 		    setsockopt(probe_fd, IPPROTO_IP, IP_TOS, (char *)&settos, sizeof(int)) < 0)
358 			perror("Warning: error setting QOS sockopts");
359 
360 		dst.sin_port = htons(1025);
361 		if (nroute)
362 			dst.sin_addr.s_addr = route[0];
363 
364 		sock_setmark(probe_fd);
365 
366 		if (connect(probe_fd, (struct sockaddr*)&dst, sizeof(dst)) == -1) {
367 			if (errno == EACCES) {
368 				if (broadcast_pings == 0) {
369 					fprintf(stderr, "Do you want to ping broadcast? Then -b\n");
370 					exit(2);
371 				}
372 				fprintf(stderr, "WARNING: pinging broadcast address\n");
373 				if (setsockopt(probe_fd, SOL_SOCKET, SO_BROADCAST,
374 					       &broadcast_pings, sizeof(broadcast_pings)) < 0) {
375 					perror ("can't set broadcasting");
376 					exit(2);
377 				}
378 				if (connect(probe_fd, (struct sockaddr*)&dst, sizeof(dst)) == -1) {
379 					perror("connect");
380 					exit(2);
381 				}
382 			} else {
383 				perror("connect");
384 				exit(2);
385 			}
386 		}
387 		alen = sizeof(source);
388 		if (getsockname(probe_fd, (struct sockaddr*)&source, &alen) == -1) {
389 			perror("getsockname");
390 			exit(2);
391 		}
392 		source.sin_port = 0;
393 
394 #ifndef WITHOUT_IFADDRS
395 		if (device) {
396 			struct ifaddrs *ifa0, *ifa;
397 			int ret;
398 
399 			ret = getifaddrs(&ifa0);
400 			if (ret) {
401 				fprintf(stderr, "gatifaddrs() failed.\n");
402 				exit(2);
403 			}
404 			for (ifa = ifa0; ifa; ifa = ifa->ifa_next) {
405 				if (!ifa->ifa_addr || ifa->ifa_addr->sa_family != AF_INET)
406 					continue;
407 				if (!strncmp(ifa->ifa_name, device, sizeof(device) - 1) &&
408 				    !memcmp(&((struct sockaddr_in *)ifa->ifa_addr)->sin_addr,
409 					    &source.sin_addr, sizeof(source.sin_addr)))
410 					break;
411 			}
412 			freeifaddrs(ifa0);
413 			if (!ifa)
414 				fprintf(stderr, "ping: Warning: source address might be selected on device other than %s.\n", device);
415 		}
416 #endif
417 		close(probe_fd);
418 	} while (0);
419 
420 	if (whereto.sin_addr.s_addr == 0)
421 		whereto.sin_addr.s_addr = source.sin_addr.s_addr;
422 
423 	if (icmp_sock < 0) {
424 		errno = socket_errno;
425 		perror("ping: icmp open socket");
426 		exit(2);
427 	}
428 
429 	if (device) {
430 		struct ifreq ifr;
431 
432 		memset(&ifr, 0, sizeof(ifr));
433 		strncpy(ifr.ifr_name, device, IFNAMSIZ-1);
434 		if (ioctl(icmp_sock, SIOCGIFINDEX, &ifr) < 0) {
435 			fprintf(stderr, "ping: unknown iface %s\n", device);
436 			exit(2);
437 		}
438 		cmsg.ipi.ipi_ifindex = ifr.ifr_ifindex;
439 		cmsg_len = sizeof(cmsg);
440 	}
441 
442 	if (broadcast_pings || IN_MULTICAST(ntohl(whereto.sin_addr.s_addr))) {
443 		if (uid) {
444 			if (interval < 1000) {
445 				fprintf(stderr, "ping: broadcast ping with too short interval.\n");
446 				exit(2);
447 			}
448 			if (pmtudisc >= 0 && pmtudisc != IP_PMTUDISC_DO) {
449 				fprintf(stderr, "ping: broadcast ping does not fragment.\n");
450 				exit(2);
451 			}
452 		}
453 		if (pmtudisc < 0)
454 			pmtudisc = IP_PMTUDISC_DO;
455 	}
456 
457 	if (pmtudisc >= 0) {
458 		if (setsockopt(icmp_sock, SOL_IP, IP_MTU_DISCOVER, &pmtudisc, sizeof(pmtudisc)) == -1) {
459 			perror("ping: IP_MTU_DISCOVER");
460 			exit(2);
461 		}
462 	}
463 
464 	if ((options&F_STRICTSOURCE) &&
465 	    bind(icmp_sock, (struct sockaddr*)&source, sizeof(source)) == -1) {
466 		perror("bind");
467 		exit(2);
468 	}
469 
470 	if (!using_ping_socket) {
471 		struct icmp_filter filt;
472 		filt.data = ~((1<<ICMP_SOURCE_QUENCH)|
473 			      (1<<ICMP_DEST_UNREACH)|
474 			      (1<<ICMP_TIME_EXCEEDED)|
475 			      (1<<ICMP_PARAMETERPROB)|
476 			      (1<<ICMP_REDIRECT)|
477 			      (1<<ICMP_ECHOREPLY));
478 		if (setsockopt(icmp_sock, SOL_RAW, ICMP_FILTER, (char*)&filt, sizeof(filt)) == -1)
479 			perror("WARNING: setsockopt(ICMP_FILTER)");
480 	}
481 
482 	hold = 1;
483 	if (setsockopt(icmp_sock, SOL_IP, IP_RECVERR, (char *)&hold, sizeof(hold)))
484 		fprintf(stderr, "WARNING: your kernel is veeery old. No problems.\n");
485 	if (using_ping_socket) {
486 		if (setsockopt(icmp_sock, SOL_IP, IP_RECVTTL, (char *)&hold, sizeof(hold)))
487 			perror("WARNING: setsockopt(IP_RECVTTL)");
488 		if (setsockopt(icmp_sock, SOL_IP, IP_RETOPTS, (char *)&hold, sizeof(hold)))
489 			perror("WARNING: setsockopt(IP_RETOPTS)");
490 	}
491 
492 	/* record route option */
493 	if (options & F_RROUTE) {
494 		memset(rspace, 0, sizeof(rspace));
495 		rspace[0] = IPOPT_NOP;
496 		rspace[1+IPOPT_OPTVAL] = IPOPT_RR;
497 		rspace[1+IPOPT_OLEN] = sizeof(rspace)-1;
498 		rspace[1+IPOPT_OFFSET] = IPOPT_MINOFF;
499 		optlen = 40;
500 		if (setsockopt(icmp_sock, IPPROTO_IP, IP_OPTIONS, rspace, sizeof(rspace)) < 0) {
501 			perror("ping: record route");
502 			exit(2);
503 		}
504 	}
505 	if (options & F_TIMESTAMP) {
506 		memset(rspace, 0, sizeof(rspace));
507 		rspace[0] = IPOPT_TIMESTAMP;
508 		rspace[1] = (ts_type==IPOPT_TS_TSONLY ? 40 : 36);
509 		rspace[2] = 5;
510 		rspace[3] = ts_type;
511 		if (ts_type == IPOPT_TS_PRESPEC) {
512 			int i;
513 			rspace[1] = 4+nroute*8;
514 			for (i=0; i<nroute; i++)
515 				*(__u32*)&rspace[4+i*8] = route[i];
516 		}
517 		if (setsockopt(icmp_sock, IPPROTO_IP, IP_OPTIONS, rspace, rspace[1]) < 0) {
518 			rspace[3] = 2;
519 			if (setsockopt(icmp_sock, IPPROTO_IP, IP_OPTIONS, rspace, rspace[1]) < 0) {
520 				perror("ping: ts option");
521 				exit(2);
522 			}
523 		}
524 		optlen = 40;
525 	}
526 	if (options & F_SOURCEROUTE) {
527 		int i;
528 		memset(rspace, 0, sizeof(rspace));
529 		rspace[0] = IPOPT_NOOP;
530 		rspace[1+IPOPT_OPTVAL] = (options & F_SO_DONTROUTE) ? IPOPT_SSRR
531 			: IPOPT_LSRR;
532 		rspace[1+IPOPT_OLEN] = 3 + nroute*4;
533 		rspace[1+IPOPT_OFFSET] = IPOPT_MINOFF;
534 		for (i=0; i<nroute; i++)
535 			*(__u32*)&rspace[4+i*4] = route[i];
536 
537 		if (setsockopt(icmp_sock, IPPROTO_IP, IP_OPTIONS, rspace, 4 + nroute*4) < 0) {
538 			perror("ping: record route");
539 			exit(2);
540 		}
541 		optlen = 40;
542 	}
543 
544 	/* Estimate memory eaten by single packet. It is rough estimate.
545 	 * Actually, for small datalen's it depends on kernel side a lot. */
546 	hold = datalen + 8;
547 	hold += ((hold+511)/512)*(optlen + 20 + 16 + 64 + 160);
548 	sock_setbufs(icmp_sock, hold);
549 
550 	if (broadcast_pings) {
551 		if (setsockopt(icmp_sock, SOL_SOCKET, SO_BROADCAST,
552 			       &broadcast_pings, sizeof(broadcast_pings)) < 0) {
553 			perror ("ping: can't set broadcasting");
554 			exit(2);
555 		}
556 	}
557 
558 	if (options & F_NOLOOP) {
559 		int loop = 0;
560 		if (setsockopt(icmp_sock, IPPROTO_IP, IP_MULTICAST_LOOP,
561 							&loop, 1) == -1) {
562 			perror ("ping: can't disable multicast loopback");
563 			exit(2);
564 		}
565 	}
566 	if (options & F_TTL) {
567 		int ittl = ttl;
568 		if (setsockopt(icmp_sock, IPPROTO_IP, IP_MULTICAST_TTL,
569 							&ttl, 1) == -1) {
570 			perror ("ping: can't set multicast time-to-live");
571 			exit(2);
572 		}
573 		if (setsockopt(icmp_sock, IPPROTO_IP, IP_TTL,
574 							&ittl, sizeof(ittl)) == -1) {
575 			perror ("ping: can't set unicast time-to-live");
576 			exit(2);
577 		}
578 	}
579 
580 	if (datalen > 0xFFFF - 8 - optlen - 20) {
581 		if (uid || datalen > sizeof(outpack)-8) {
582 			fprintf(stderr, "Error: packet size %d is too large. Maximum is %d\n", datalen, 0xFFFF-8-20-optlen);
583 			exit(2);
584 		}
585 		/* Allow small oversize to root yet. It will cause EMSGSIZE. */
586 		fprintf(stderr, "WARNING: packet size %d is too large. Maximum is %d\n", datalen, 0xFFFF-8-20-optlen);
587 	}
588 
589 	if (datalen >= sizeof(struct timeval))	/* can we time transfer */
590 		timing = 1;
591 	packlen = datalen + MAXIPLEN + MAXICMPLEN;
592 	if (!(packet = (u_char *)malloc((u_int)packlen))) {
593 		fprintf(stderr, "ping: out of memory.\n");
594 		exit(2);
595 	}
596 
597 	printf("PING %s (%s) ", hostname, inet_ntoa(whereto.sin_addr));
598 	if (device || (options&F_STRICTSOURCE))
599 		printf("from %s %s: ", inet_ntoa(source.sin_addr), device ?: "");
600 	printf("%d(%d) bytes of data.\n", datalen, datalen+8+optlen+20);
601 
602 	setup(icmp_sock);
603 
604 	main_loop(icmp_sock, packet, packlen);
605 }
606 
607 
receive_error_msg()608 int receive_error_msg()
609 {
610 	int res;
611 	char cbuf[512];
612 	struct iovec  iov;
613 	struct msghdr msg;
614 	struct cmsghdr *cmsg;
615 	struct sock_extended_err *e;
616 	struct icmphdr icmph;
617 	struct sockaddr_in target;
618 	int net_errors = 0;
619 	int local_errors = 0;
620 	int saved_errno = errno;
621 
622 	iov.iov_base = &icmph;
623 	iov.iov_len = sizeof(icmph);
624 	msg.msg_name = (void*)&target;
625 	msg.msg_namelen = sizeof(target);
626 	msg.msg_iov = &iov;
627 	msg.msg_iovlen = 1;
628 	msg.msg_flags = 0;
629 	msg.msg_control = cbuf;
630 	msg.msg_controllen = sizeof(cbuf);
631 
632 	res = recvmsg(icmp_sock, &msg, MSG_ERRQUEUE|MSG_DONTWAIT);
633 	if (res < 0)
634 		goto out;
635 
636 	e = NULL;
637 	for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
638 		if (cmsg->cmsg_level == SOL_IP) {
639 			if (cmsg->cmsg_type == IP_RECVERR)
640 				e = (struct sock_extended_err *)CMSG_DATA(cmsg);
641 		}
642 	}
643 	if (e == NULL)
644 		abort();
645 
646 	if (e->ee_origin == SO_EE_ORIGIN_LOCAL) {
647 		local_errors++;
648 		if (options & F_QUIET)
649 			goto out;
650 		if (options & F_FLOOD)
651 			write_stdout("E", 1);
652 		else if (e->ee_errno != EMSGSIZE)
653 			fprintf(stderr, "ping: local error: %s\n", strerror(e->ee_errno));
654 		else
655 			fprintf(stderr, "ping: local error: Message too long, mtu=%u\n", e->ee_info);
656 		nerrors++;
657 	} else if (e->ee_origin == SO_EE_ORIGIN_ICMP) {
658 		struct sockaddr_in *sin = (struct sockaddr_in*)(e+1);
659 		int error_pkt;
660 
661 		if (res < sizeof(icmph) ||
662 		    target.sin_addr.s_addr != whereto.sin_addr.s_addr ||
663 		    icmph.type != ICMP_ECHO ||
664 		    !is_ours(icmph.un.echo.id)) {
665 			/* Not our error, not an error at all. Clear. */
666 			saved_errno = 0;
667 			goto out;
668 		}
669 
670 		error_pkt = (e->ee_type != ICMP_REDIRECT &&
671 			     e->ee_type != ICMP_SOURCE_QUENCH);
672 		if (error_pkt) {
673 			acknowledge(ntohs(icmph.un.echo.sequence));
674 			net_errors++;
675 			nerrors++;
676 		}
677 		else {
678 			saved_errno = 0;
679 		}
680 
681 		if (!using_ping_socket && !working_recverr) {
682 			struct icmp_filter filt;
683 			working_recverr = 1;
684 			/* OK, it works. Add stronger filter. */
685 			filt.data = ~((1<<ICMP_SOURCE_QUENCH)|
686 				      (1<<ICMP_REDIRECT)|
687 				      (1<<ICMP_ECHOREPLY));
688 			if (setsockopt(icmp_sock, SOL_RAW, ICMP_FILTER, (char*)&filt, sizeof(filt)) == -1)
689 				perror("\rWARNING: setsockopt(ICMP_FILTER)");
690 		}
691 
692 		if (options & F_QUIET)
693 			goto out;
694 		if (options & F_FLOOD) {
695 			if (error_pkt)
696 				write_stdout("\bE", 2);
697 		} else {
698 			print_timestamp();
699 			printf("From %s: icmp_seq=%u ", pr_addr(sin->sin_addr.s_addr), ntohs(icmph.un.echo.sequence));
700 			pr_icmph(e->ee_type, e->ee_code, e->ee_info, NULL);
701 			fflush(stdout);
702 		}
703 	}
704 
705 out:
706 	errno = saved_errno;
707 	return net_errors ? : -local_errors;
708 }
709 
710 /*
711  * pinger --
712  * 	Compose and transmit an ICMP ECHO REQUEST packet.  The IP packet
713  * will be added on by the kernel.  The ID field is our UNIX process ID,
714  * and the sequence number is an ascending integer.  The first 8 bytes
715  * of the data portion are used to hold a UNIX "timeval" struct in VAX
716  * byte-order, to compute the round-trip time.
717  */
send_probe()718 int send_probe()
719 {
720 	struct icmphdr *icp;
721 	int cc;
722 	int i;
723 
724 	icp = (struct icmphdr *)outpack;
725 	icp->type = ICMP_ECHO;
726 	icp->code = 0;
727 	icp->checksum = 0;
728 	icp->un.echo.sequence = htons(ntransmitted+1);
729 	icp->un.echo.id = ident;			/* ID */
730 
731 	rcvd_clear(ntransmitted+1);
732 
733 	if (timing) {
734 		if (options&F_LATENCY) {
735 			struct timeval tmp_tv;
736 			gettimeofday(&tmp_tv, NULL);
737 			memcpy(icp+1, &tmp_tv, sizeof(tmp_tv));
738 		} else {
739 			memset(icp+1, 0, sizeof(struct timeval));
740 		}
741 	}
742 
743 	cc = datalen + 8;			/* skips ICMP portion */
744 
745 	/* compute ICMP checksum here */
746 	icp->checksum = in_cksum((u_short *)icp, cc, 0);
747 
748 	if (timing && !(options&F_LATENCY)) {
749 		struct timeval tmp_tv;
750 		gettimeofday(&tmp_tv, NULL);
751 		memcpy(icp+1, &tmp_tv, sizeof(tmp_tv));
752 		icp->checksum = in_cksum((u_short *)&tmp_tv, sizeof(tmp_tv), ~icp->checksum);
753 	}
754 
755 	do {
756 		static struct iovec iov = {outpack, 0};
757 		static struct msghdr m = { &whereto, sizeof(whereto),
758 						   &iov, 1, &cmsg, 0, 0 };
759 		m.msg_controllen = cmsg_len;
760 		iov.iov_len = cc;
761 
762 		i = sendmsg(icmp_sock, &m, confirm);
763 		confirm = 0;
764 	} while (0);
765 
766 	return (cc == i ? 0 : i);
767 }
768 
769 /*
770  * parse_reply --
771  *	Print out the packet, if it came from us.  This logic is necessary
772  * because ALL readers of the ICMP socket get a copy of ALL ICMP packets
773  * which arrive ('tis only fair).  This permits multiple copies of this
774  * program to be run without having intermingled output (or statistics!).
775  */
pr_echo_reply(__u8 * _icp,int len)776 void pr_echo_reply(__u8 *_icp, int len)
777 {
778 	struct icmphdr *icp = (struct icmphdr *)_icp;
779 	printf(" icmp_seq=%u", ntohs(icp->un.echo.sequence));
780 }
781 
782 int
parse_reply(struct msghdr * msg,int cc,void * addr,struct timeval * tv)783 parse_reply(struct msghdr *msg, int cc, void *addr, struct timeval *tv)
784 {
785 	struct sockaddr_in *from = addr;
786 	__u8 *buf = msg->msg_iov->iov_base;
787 	struct icmphdr *icp;
788 	struct iphdr *ip;
789 	int hlen;
790 	int csfailed;
791 	struct cmsghdr *cmsg;
792 	int ttl;
793 	__u8 *opts;
794 	int optlen;
795 
796 	/* Check the IP header */
797 	ip = (struct iphdr *)buf;
798 	if (!using_ping_socket) {
799 		hlen = ip->ihl*4;
800 		if (cc < hlen + 8 || ip->ihl < 5) {
801 			if (options & F_VERBOSE)
802 				fprintf(stderr, "ping: packet too short (%d bytes) from %s\n", cc,
803 					pr_addr(from->sin_addr.s_addr));
804 			return 1;
805 		}
806 		ttl = ip->ttl;
807 		opts = buf + sizeof(struct iphdr);
808 		optlen = hlen - sizeof(struct iphdr);
809 	} else {
810 		hlen = 0;
811 		ttl = 0;
812 		opts = buf;
813 		optlen = 0;
814 		for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
815 			if (cmsg->cmsg_level != SOL_IP)
816 				continue;
817 			if (cmsg->cmsg_type == IP_TTL) {
818 				if (cmsg->cmsg_len < sizeof(int))
819 					continue;
820 				ttl = *(int *) CMSG_DATA(cmsg);
821 			} else if (cmsg->cmsg_type == IP_RETOPTS) {
822 				opts = (__u8 *) CMSG_DATA(cmsg);
823 				optlen = cmsg->cmsg_len;
824 			}
825 		}
826 	}
827 
828 	/* Now the ICMP part */
829 	cc -= hlen;
830 	icp = (struct icmphdr *)(buf + hlen);
831 	csfailed = in_cksum((u_short *)icp, cc, 0);
832 
833 	if (icp->type == ICMP_ECHOREPLY) {
834 		if (!is_ours(icp->un.echo.id))
835 			return 1;			/* 'Twas not our ECHO */
836 		if (gather_statistics((__u8*)icp, sizeof(*icp), cc,
837 				      ntohs(icp->un.echo.sequence),
838 				      ttl, 0, tv, pr_addr(from->sin_addr.s_addr),
839 				      pr_echo_reply))
840 			return 0;
841 	} else {
842 		/* We fall here when a redirect or source quench arrived.
843 		 * Also this branch processes icmp errors, when IP_RECVERR
844 		 * is broken. */
845 
846 		switch (icp->type) {
847 		case ICMP_ECHO:
848 			/* MUST NOT */
849 			return 1;
850 		case ICMP_SOURCE_QUENCH:
851 		case ICMP_REDIRECT:
852 		case ICMP_DEST_UNREACH:
853 		case ICMP_TIME_EXCEEDED:
854 		case ICMP_PARAMETERPROB:
855 			{
856 				struct iphdr * iph = (struct  iphdr *)(&icp[1]);
857 				struct icmphdr *icp1 = (struct icmphdr*)((unsigned char *)iph + iph->ihl*4);
858 				int error_pkt;
859 				if (cc < 8+sizeof(struct iphdr)+8 ||
860 				    cc < 8+iph->ihl*4+8)
861 					return 1;
862 				if (icp1->type != ICMP_ECHO ||
863 				    iph->daddr != whereto.sin_addr.s_addr ||
864 				    !is_ours(icp1->un.echo.id))
865 					return 1;
866 				error_pkt = (icp->type != ICMP_REDIRECT &&
867 					     icp->type != ICMP_SOURCE_QUENCH);
868 				if (error_pkt) {
869 					acknowledge(ntohs(icp1->un.echo.sequence));
870 					if (working_recverr) {
871 						return 0;
872 					} else {
873 						static int once;
874 						/* Sigh, IP_RECVERR for raw socket
875 						 * was broken until 2.4.9. So, we ignore
876 						 * the first error and warn on the second.
877 						 */
878 						if (once++ == 1)
879 							fprintf(stderr, "\rWARNING: kernel is not very fresh, upgrade is recommended.\n");
880 						if (once == 1)
881 							return 0;
882 					}
883 				}
884 				nerrors+=error_pkt;
885 				if (options&F_QUIET)
886 					return !error_pkt;
887 				if (options & F_FLOOD) {
888 					if (error_pkt)
889 						write_stdout("\bE", 2);
890 					return !error_pkt;
891 				}
892 				print_timestamp();
893 				printf("From %s: icmp_seq=%u ",
894 				       pr_addr(from->sin_addr.s_addr),
895 				       ntohs(icp1->un.echo.sequence));
896 				if (csfailed)
897 					printf("(BAD CHECKSUM)");
898 				pr_icmph(icp->type, icp->code, ntohl(icp->un.gateway), icp);
899 				return !error_pkt;
900 			}
901 		default:
902 			/* MUST NOT */
903 			break;
904 		}
905 		if ((options & F_FLOOD) && !(options & (F_VERBOSE|F_QUIET))) {
906 			if (!csfailed)
907 				write_stdout("!E", 2);
908 			else
909 				write_stdout("!EC", 3);
910 			return 0;
911 		}
912 		if (!(options & F_VERBOSE) || uid)
913 			return 0;
914 		if (options & F_PTIMEOFDAY) {
915 			struct timeval recv_time;
916 			gettimeofday(&recv_time, NULL);
917 			printf("%lu.%06lu ", (unsigned long)recv_time.tv_sec, (unsigned long)recv_time.tv_usec);
918 		}
919 		printf("From %s: ", pr_addr(from->sin_addr.s_addr));
920 		if (csfailed) {
921 			printf("(BAD CHECKSUM)\n");
922 			return 0;
923 		}
924 		pr_icmph(icp->type, icp->code, ntohl(icp->un.gateway), icp);
925 		return 0;
926 	}
927 
928 	if (!(options & F_FLOOD)) {
929 		pr_options(opts, optlen + sizeof(struct iphdr));
930 
931 		if (options & F_AUDIBLE)
932 			putchar('\a');
933 		putchar('\n');
934 		fflush(stdout);
935 	} else {
936 		putchar('\a');
937 		fflush(stdout);
938 	}
939 	return 0;
940 }
941 
942 
943 #if BYTE_ORDER == LITTLE_ENDIAN
944 # define ODDBYTE(v)	(v)
945 #elif BYTE_ORDER == BIG_ENDIAN
946 # define ODDBYTE(v)	((u_short)(v) << 8)
947 #else
948 # define ODDBYTE(v)	htons((u_short)(v) << 8)
949 #endif
950 
951 u_short
in_cksum(const u_short * addr,register int len,u_short csum)952 in_cksum(const u_short *addr, register int len, u_short csum)
953 {
954 	register int nleft = len;
955 	const u_short *w = addr;
956 	register u_short answer;
957 	register int sum = csum;
958 
959 	/*
960 	 *  Our algorithm is simple, using a 32 bit accumulator (sum),
961 	 *  we add sequential 16 bit words to it, and at the end, fold
962 	 *  back all the carry bits from the top 16 bits into the lower
963 	 *  16 bits.
964 	 */
965 	while (nleft > 1)  {
966 		sum += *w++;
967 		nleft -= 2;
968 	}
969 
970 	/* mop up an odd byte, if necessary */
971 	if (nleft == 1)
972 		sum += ODDBYTE(*(u_char *)w); /* le16toh() may be unavailable on old systems */
973 
974 	/*
975 	 * add back carry outs from top 16 bits to low 16 bits
976 	 */
977 	sum = (sum >> 16) + (sum & 0xffff);	/* add hi 16 to low 16 */
978 	sum += (sum >> 16);			/* add carry */
979 	answer = ~sum;				/* truncate to 16 bits */
980 	return (answer);
981 }
982 
983 /*
984  * pr_icmph --
985  *	Print a descriptive string about an ICMP header.
986  */
pr_icmph(__u8 type,__u8 code,__u32 info,struct icmphdr * icp)987 void pr_icmph(__u8 type, __u8 code, __u32 info, struct icmphdr *icp)
988 {
989 	switch(type) {
990 	case ICMP_ECHOREPLY:
991 		printf("Echo Reply\n");
992 		/* XXX ID + Seq + Data */
993 		break;
994 	case ICMP_DEST_UNREACH:
995 		switch(code) {
996 		case ICMP_NET_UNREACH:
997 			printf("Destination Net Unreachable\n");
998 			break;
999 		case ICMP_HOST_UNREACH:
1000 			printf("Destination Host Unreachable\n");
1001 			break;
1002 		case ICMP_PROT_UNREACH:
1003 			printf("Destination Protocol Unreachable\n");
1004 			break;
1005 		case ICMP_PORT_UNREACH:
1006 			printf("Destination Port Unreachable\n");
1007 			break;
1008 		case ICMP_FRAG_NEEDED:
1009 			printf("Frag needed and DF set (mtu = %u)\n", info);
1010 			break;
1011 		case ICMP_SR_FAILED:
1012 			printf("Source Route Failed\n");
1013 			break;
1014 		case ICMP_NET_UNKNOWN:
1015 			printf("Destination Net Unknown\n");
1016 			break;
1017 		case ICMP_HOST_UNKNOWN:
1018 			printf("Destination Host Unknown\n");
1019 			break;
1020 		case ICMP_HOST_ISOLATED:
1021 			printf("Source Host Isolated\n");
1022 			break;
1023 		case ICMP_NET_ANO:
1024 			printf("Destination Net Prohibited\n");
1025 			break;
1026 		case ICMP_HOST_ANO:
1027 			printf("Destination Host Prohibited\n");
1028 			break;
1029 		case ICMP_NET_UNR_TOS:
1030 			printf("Destination Net Unreachable for Type of Service\n");
1031 			break;
1032 		case ICMP_HOST_UNR_TOS:
1033 			printf("Destination Host Unreachable for Type of Service\n");
1034 			break;
1035 		case ICMP_PKT_FILTERED:
1036 			printf("Packet filtered\n");
1037 			break;
1038 		case ICMP_PREC_VIOLATION:
1039 			printf("Precedence Violation\n");
1040 			break;
1041 		case ICMP_PREC_CUTOFF:
1042 			printf("Precedence Cutoff\n");
1043 			break;
1044 		default:
1045 			printf("Dest Unreachable, Bad Code: %d\n", code);
1046 			break;
1047 		}
1048 		if (icp && (options & F_VERBOSE))
1049 			pr_iph((struct iphdr*)(icp + 1));
1050 		break;
1051 	case ICMP_SOURCE_QUENCH:
1052 		printf("Source Quench\n");
1053 		if (icp && (options & F_VERBOSE))
1054 			pr_iph((struct iphdr*)(icp + 1));
1055 		break;
1056 	case ICMP_REDIRECT:
1057 		switch(code) {
1058 		case ICMP_REDIR_NET:
1059 			printf("Redirect Network");
1060 			break;
1061 		case ICMP_REDIR_HOST:
1062 			printf("Redirect Host");
1063 			break;
1064 		case ICMP_REDIR_NETTOS:
1065 			printf("Redirect Type of Service and Network");
1066 			break;
1067 		case ICMP_REDIR_HOSTTOS:
1068 			printf("Redirect Type of Service and Host");
1069 			break;
1070 		default:
1071 			printf("Redirect, Bad Code: %d", code);
1072 			break;
1073 		}
1074 		printf("(New nexthop: %s)\n", pr_addr(icp ? icp->un.gateway : info));
1075 		if (icp && (options & F_VERBOSE))
1076 			pr_iph((struct iphdr*)(icp + 1));
1077 		break;
1078 	case ICMP_ECHO:
1079 		printf("Echo Request\n");
1080 		/* XXX ID + Seq + Data */
1081 		break;
1082 	case ICMP_TIME_EXCEEDED:
1083 		switch(code) {
1084 		case ICMP_EXC_TTL:
1085 			printf("Time to live exceeded\n");
1086 			break;
1087 		case ICMP_EXC_FRAGTIME:
1088 			printf("Frag reassembly time exceeded\n");
1089 			break;
1090 		default:
1091 			printf("Time exceeded, Bad Code: %d\n", code);
1092 			break;
1093 		}
1094 		if (icp && (options & F_VERBOSE))
1095 			pr_iph((struct iphdr*)(icp + 1));
1096 		break;
1097 	case ICMP_PARAMETERPROB:
1098 		printf("Parameter problem: pointer = %u\n", icp ? (ntohl(icp->un.gateway)>>24) : info);
1099 		if (icp && (options & F_VERBOSE))
1100 			pr_iph((struct iphdr*)(icp + 1));
1101 		break;
1102 	case ICMP_TIMESTAMP:
1103 		printf("Timestamp\n");
1104 		/* XXX ID + Seq + 3 timestamps */
1105 		break;
1106 	case ICMP_TIMESTAMPREPLY:
1107 		printf("Timestamp Reply\n");
1108 		/* XXX ID + Seq + 3 timestamps */
1109 		break;
1110 	case ICMP_INFO_REQUEST:
1111 		printf("Information Request\n");
1112 		/* XXX ID + Seq */
1113 		break;
1114 	case ICMP_INFO_REPLY:
1115 		printf("Information Reply\n");
1116 		/* XXX ID + Seq */
1117 		break;
1118 #ifdef ICMP_MASKREQ
1119 	case ICMP_MASKREQ:
1120 		printf("Address Mask Request\n");
1121 		break;
1122 #endif
1123 #ifdef ICMP_MASKREPLY
1124 	case ICMP_MASKREPLY:
1125 		printf("Address Mask Reply\n");
1126 		break;
1127 #endif
1128 	default:
1129 		printf("Bad ICMP type: %d\n", type);
1130 	}
1131 }
1132 
pr_options(unsigned char * cp,int hlen)1133 void pr_options(unsigned char * cp, int hlen)
1134 {
1135 	int i, j;
1136 	int optlen, totlen;
1137 	unsigned char * optptr;
1138 	static int old_rrlen;
1139 	static char old_rr[MAX_IPOPTLEN];
1140 
1141 	totlen = hlen-sizeof(struct iphdr);
1142 	optptr = cp;
1143 
1144 	while (totlen > 0) {
1145 		if (*optptr == IPOPT_EOL)
1146 			break;
1147 		if (*optptr == IPOPT_NOP) {
1148 			totlen--;
1149 			optptr++;
1150 			printf("\nNOP");
1151 			continue;
1152 		}
1153 		cp = optptr;
1154 		optlen = optptr[1];
1155 		if (optlen < 2 || optlen > totlen)
1156 			break;
1157 
1158 		switch (*cp) {
1159 		case IPOPT_SSRR:
1160 		case IPOPT_LSRR:
1161 			printf("\n%cSRR: ", *cp==IPOPT_SSRR ? 'S' : 'L');
1162 			j = *++cp;
1163 			i = *++cp;
1164 			i -= 4;
1165 			cp++;
1166 			if (j > IPOPT_MINOFF) {
1167 				for (;;) {
1168 					__u32 address;
1169 					memcpy(&address, cp, 4);
1170 					cp += 4;
1171 					if (address == 0)
1172 						printf("\t0.0.0.0");
1173 					else
1174 						printf("\t%s", pr_addr(address));
1175 					j -= 4;
1176 					putchar('\n');
1177 					if (j <= IPOPT_MINOFF)
1178 						break;
1179 				}
1180 			}
1181 			break;
1182 		case IPOPT_RR:
1183 			j = *++cp;		/* get length */
1184 			i = *++cp;		/* and pointer */
1185 			if (i > j)
1186 				i = j;
1187 			i -= IPOPT_MINOFF;
1188 			if (i <= 0)
1189 				break;
1190 			if (i == old_rrlen
1191 			    && !memcmp(cp, old_rr, i)
1192 			    && !(options & F_FLOOD)) {
1193 				printf("\t(same route)");
1194 				i = ((i + 3) / 4) * 4;
1195 				cp += i;
1196 				break;
1197 			}
1198 			old_rrlen = i;
1199 			memcpy(old_rr, (char *)cp, i);
1200 			printf("\nRR: ");
1201 			cp++;
1202 			for (;;) {
1203 				__u32 address;
1204 				memcpy(&address, cp, 4);
1205 				cp += 4;
1206 				if (address == 0)
1207 					printf("\t0.0.0.0");
1208 				else
1209 					printf("\t%s", pr_addr(address));
1210 				i -= 4;
1211 				putchar('\n');
1212 				if (i <= 0)
1213 					break;
1214 			}
1215 			break;
1216 		case IPOPT_TS:
1217 		{
1218 			int stdtime = 0, nonstdtime = 0;
1219 			__u8 flags;
1220 			j = *++cp;		/* get length */
1221 			i = *++cp;		/* and pointer */
1222 			if (i > j)
1223 				i = j;
1224 			i -= 5;
1225 			if (i <= 0)
1226 				break;
1227 			flags = *++cp;
1228 			printf("\nTS: ");
1229 			cp++;
1230 			for (;;) {
1231 				long l;
1232 
1233 				if ((flags&0xF) != IPOPT_TS_TSONLY) {
1234 					__u32 address;
1235 					memcpy(&address, cp, 4);
1236 					cp += 4;
1237 					if (address == 0)
1238 						printf("\t0.0.0.0");
1239 					else
1240 						printf("\t%s", pr_addr(address));
1241 					i -= 4;
1242 					if (i <= 0)
1243 						break;
1244 				}
1245 				l = *cp++;
1246 				l = (l<<8) + *cp++;
1247 				l = (l<<8) + *cp++;
1248 				l = (l<<8) + *cp++;
1249 
1250 				if  (l & 0x80000000) {
1251 					if (nonstdtime==0)
1252 						printf("\t%ld absolute not-standard", l&0x7fffffff);
1253 					else
1254 						printf("\t%ld not-standard", (l&0x7fffffff) - nonstdtime);
1255 					nonstdtime = l&0x7fffffff;
1256 				} else {
1257 					if (stdtime==0)
1258 						printf("\t%ld absolute", l);
1259 					else
1260 						printf("\t%ld", l - stdtime);
1261 					stdtime = l;
1262 				}
1263 				i -= 4;
1264 				putchar('\n');
1265 				if (i <= 0)
1266 					break;
1267 			}
1268 			if (flags>>4)
1269 				printf("Unrecorded hops: %d\n", flags>>4);
1270 			break;
1271 		}
1272 		default:
1273 			printf("\nunknown option %x", *cp);
1274 			break;
1275 		}
1276 		totlen -= optlen;
1277 		optptr += optlen;
1278 	}
1279 }
1280 
1281 
1282 /*
1283  * pr_iph --
1284  *	Print an IP header with options.
1285  */
pr_iph(struct iphdr * ip)1286 void pr_iph(struct iphdr *ip)
1287 {
1288 	int hlen;
1289 	u_char *cp;
1290 
1291 	hlen = ip->ihl << 2;
1292 	cp = (u_char *)ip + 20;		/* point to options */
1293 
1294 	printf("Vr HL TOS  Len   ID Flg  off TTL Pro  cks      Src      Dst Data\n");
1295 	printf(" %1x  %1x  %02x %04x %04x",
1296 	       ip->version, ip->ihl, ip->tos, ip->tot_len, ip->id);
1297 	printf("   %1x %04x", ((ip->frag_off) & 0xe000) >> 13,
1298 	       (ip->frag_off) & 0x1fff);
1299 	printf("  %02x  %02x %04x", ip->ttl, ip->protocol, ip->check);
1300 	printf(" %s ", inet_ntoa(*(struct in_addr *)&ip->saddr));
1301 	printf(" %s ", inet_ntoa(*(struct in_addr *)&ip->daddr));
1302 	printf("\n");
1303 	pr_options(cp, hlen);
1304 }
1305 
1306 /*
1307  * pr_addr --
1308  *	Return an ascii host address as a dotted quad and optionally with
1309  * a hostname.
1310  */
1311 char *
pr_addr(__u32 addr)1312 pr_addr(__u32 addr)
1313 {
1314 	struct hostent *hp;
1315 	static char buf[4096];
1316 
1317 	in_pr_addr = !setjmp(pr_addr_jmp);
1318 
1319 	if (exiting || (options & F_NUMERIC) ||
1320 	    !(hp = gethostbyaddr((char *)&addr, 4, AF_INET)))
1321 		sprintf(buf, "%s", inet_ntoa(*(struct in_addr *)&addr));
1322 	else {
1323 		char *s;
1324 #if USE_IDN
1325 		if (idna_to_unicode_lzlz(hp->h_name, &s, 0) != IDNA_SUCCESS)
1326 			s = NULL;
1327 #else
1328 		s = NULL;
1329 #endif
1330 		snprintf(buf, sizeof(buf), "%s (%s)", s ? s : hp->h_name,
1331 			 inet_ntoa(*(struct in_addr *)&addr));
1332 #if USE_IDN
1333 		free(s);
1334 #endif
1335 	}
1336 
1337 	in_pr_addr = 0;
1338 
1339 	return(buf);
1340 }
1341 
1342 
1343 /* Set Type of Service (TOS) and other Quality of Service relating bits */
parsetos(char * str)1344 int parsetos(char *str)
1345 {
1346 	const char *cp;
1347 	int tos;
1348 	char *ep;
1349 
1350 	/* handle both hex and decimal values */
1351 	if (str[0] == '0' && (str[1] == 'x' || str[1] == 'X')) {
1352 		cp = str + 2;
1353 		tos = (int)strtol(cp, &ep, 16);
1354 	} else
1355 		tos = (int)strtol(str, &ep, 10);
1356 
1357 	/* doesn't look like decimal or hex, eh? */
1358 	if (*ep != '\0') {
1359 		fprintf(stderr, "ping: \"%s\" bad value for TOS\n", str);
1360 		exit(2);
1361 	}
1362 
1363 	if (tos > TOS_MAX) {
1364 		fprintf(stderr, "ping: the decimal value of TOS bits must be 0-254 (or zero)\n");
1365 		exit(2);
1366 	}
1367 	return(tos);
1368 }
1369 
1370 #include <linux/filter.h>
1371 
install_filter(void)1372 void install_filter(void)
1373 {
1374 	static int once;
1375 	static struct sock_filter insns[] = {
1376 		BPF_STMT(BPF_LDX|BPF_B|BPF_MSH, 0), /* Skip IP header. F..g BSD... Look into ping6. */
1377 		BPF_STMT(BPF_LD|BPF_H|BPF_IND, 4), /* Load icmp echo ident */
1378 		BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, 0xAAAA, 0, 1), /* Ours? */
1379 		BPF_STMT(BPF_RET|BPF_K, ~0U), /* Yes, it passes. */
1380 		BPF_STMT(BPF_LD|BPF_B|BPF_IND, 0), /* Load icmp type */
1381 		BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, ICMP_ECHOREPLY, 1, 0), /* Echo? */
1382 		BPF_STMT(BPF_RET|BPF_K, 0xFFFFFFF), /* No. It passes. */
1383 		BPF_STMT(BPF_RET|BPF_K, 0) /* Echo with wrong ident. Reject. */
1384 	};
1385 	static struct sock_fprog filter = {
1386 		sizeof insns / sizeof(insns[0]),
1387 		insns
1388 	};
1389 
1390 	if (once || using_ping_socket)
1391 		return;
1392 	once = 1;
1393 
1394 	/* Patch bpflet for current identifier. */
1395 	insns[2] = (struct sock_filter)BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, htons(ident), 0, 1);
1396 
1397 	if (setsockopt(icmp_sock, SOL_SOCKET, SO_ATTACH_FILTER, &filter, sizeof(filter)))
1398 		perror("WARNING: failed to install socket filter\n");
1399 }
1400 
1401 #define USAGE_NEWLINE	"\n           "
1402 
usage(void)1403 void usage(void)
1404 {
1405 	fprintf(stderr,
1406 		"Usage: ping"
1407 		" [-"
1408 			"aAbBdDfhLnOqrRUvV"
1409 		"]"
1410 		" [-c count]"
1411 		" [-i interval]"
1412 		" [-I interface]"
1413 		USAGE_NEWLINE
1414 		" [-m mark]"
1415 		" [-M pmtudisc_option]"
1416 		" [-l preload]"
1417 		" [-p pattern]"
1418 		" [-Q tos]"
1419 		USAGE_NEWLINE
1420 		" [-s packetsize]"
1421 		" [-S sndbuf]"
1422 		" [-t ttl]"
1423 		" [-T timestamp_option]"
1424 		USAGE_NEWLINE
1425 		" [-w deadline]"
1426 		" [-W timeout]"
1427 		" [hop1 ...] destination"
1428 		"\n"
1429 	);
1430 	exit(2);
1431 }
1432