xref: /titanic_41/usr/src/cmd/cmd-inet/usr.sbin/ping/ping.c (revision bd7c6f51f14365fc31d408903b38c02177384d3d)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  *
21  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
22  * Use is subject to license terms.
23  */
24 
25 /*
26  * Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T
27  * All Rights Reserved.
28  */
29 
30 /*
31  * University Copyright- Copyright (c) 1982, 1986, 1988
32  * The Regents of the University of California.
33  * All Rights Reserved.
34  *
35  * University Acknowledgment- Portions of this document are derived from
36  * software developed by the University of California, Berkeley, and its
37  * contributors.
38  */
39 
40 #include <stdio.h>
41 #include <strings.h>
42 #include <errno.h>
43 #include <fcntl.h>
44 #include <unistd.h>
45 #include <signal.h>
46 #include <limits.h>
47 #include <math.h>
48 
49 #include <sys/time.h>
50 #include <sys/param.h>
51 #include <sys/socket.h>
52 #include <sys/sockio.h>
53 #include <sys/stropts.h>
54 #include <sys/file.h>
55 #include <sys/sysmacros.h>
56 
57 #include <arpa/inet.h>
58 #include <net/if.h>
59 #include <netinet/in_systm.h>
60 #include <netinet/in.h>
61 #include <netinet/ip.h>
62 #include <netinet/ip_icmp.h>
63 #include <netinet/ip_var.h>
64 #include <netinet/ip6.h>
65 #include <netinet/icmp6.h>
66 #include <netinet/udp.h>
67 #include <netdb.h>
68 #include <stdlib.h>
69 #include <priv_utils.h>
70 
71 #include <libinetutil.h>
72 #include "ping.h"
73 
74 /*
75  * This macro is used to compare 16bit, wrapping sequence numbers. Inspired by
76  * TCP's SEQ_LEQ macro.
77  */
78 #define	PINGSEQ_LEQ(a, b)	((int16_t)((a)-(b)) <= 0)
79 
80 #define	MAX_WAIT		10	/* max sec. to wait for response */
81 #define	MAX_TRAFFIC_CLASS	255	/* max traffic class for IPv6 */
82 #define	MAX_FLOW_LABEL		0xFFFFF	/* max flow label for IPv6 */
83 #define	MAX_TOS			255	/* max type-of-service for IPv4 */
84 
85 #define	TIMEOUT			20	/* default timeout value */
86 #define	DEFAULT_DATALEN		56
87 
88 #define	MULTICAST_NOLOOP	1	/* multicast options */
89 #define	MULTICAST_TTL		2
90 #define	MULTICAST_IF		4
91 
92 #define	IF_INDEX		0	/* types of -i argument */
93 #define	IF_NAME			1
94 #define	IF_ADDR			2
95 #define	IF_ADDR6		3
96 
97 #ifdef BSD
98 #define	setbuf(s, b)	setlinebuf((s))
99 #endif /* BSD */
100 
101 
102 /* interface identification */
103 union if_id {
104 	int index;		/* interface index (e.g., 1, 2) */
105 	char *name;		/* interface name (e.g., le0, hme0) */
106 	union any_in_addr addr;	/* interface address (e.g., 10.123.4.5) */
107 };
108 
109 /* stores the interface supplied by the user */
110 struct if_entry {
111 	char *str;		/* unresolved, string input */
112 	int id_type;		/* type of ID (index, name, addr, addr6) */
113 	union if_id id;		/* ID */
114 };
115 
116 char *progname;
117 char *targethost;
118 char *nexthop;
119 
120 static int send_sock;			/* send sockets */
121 static int send_sock6;
122 static struct sockaddr_in to;		/* where to send */
123 static struct sockaddr_in6 to6;
124 static union any_in_addr gw_IP_list[MAX_GWS];	/* gateways */
125 static union any_in_addr gw_IP_list6[MAX_GWS6];
126 static int if_index = 0;		/* outgoing interface index */
127 boolean_t is_alive = _B_FALSE;		/* is target host alive */
128 struct targetaddr *current_targetaddr;	/* current target IP address to probe */
129 static struct targetaddr *targetaddr_list; /* list of IP addresses to probe */
130 static int num_targetaddrs;		/* no of target addresses to probe */
131 static int num_v4 = 0;			/* count of IPv4 addresses */
132 static int num_v6 = 0;			/* count of IPv6 addresses */
133 boolean_t verbose = _B_FALSE;		/* verbose output */
134 boolean_t stats = _B_FALSE;		/* display statistics */
135 static boolean_t settos = _B_FALSE;	/* set type-of-service value */
136 boolean_t rr_option = _B_FALSE;		/* true if using record route */
137 boolean_t send_reply = _B_FALSE;	/* Send an ICMP_{ECHO|TSTAMP}REPLY */
138 					/* that goes to target and comes back */
139 					/* to the the sender via src routing. */
140 boolean_t strict = _B_FALSE;		/* true if using strict source route */
141 boolean_t ts_option = _B_FALSE;		/* true if using timestamp option */
142 boolean_t use_icmp_ts = _B_FALSE;	/* Use ICMP timestamp request */
143 boolean_t use_udp = _B_FALSE;		/* Use UDP instead of ICMP */
144 boolean_t probe_all = _B_FALSE;		/* probe all the IP addresses */
145 boolean_t nflag = _B_FALSE;		/* do not reverse lookup addresses */
146 boolean_t bypass = _B_FALSE;		/* bypass IPsec policy */
147 static int family_input = AF_UNSPEC;	/* address family supplied by user */
148 int datalen = DEFAULT_DATALEN;		/* How much data */
149 int ts_flag;				/* timestamp flag value */
150 static int num_gw;			/* number of gateways */
151 static int eff_num_gw;			/* effective number of gateways */
152 					/* if send_reply, it's 2*num_gw+1 */
153 static int num_wraps = -1;		/* no of times 64K icmp_seq wrapped */
154 static ushort_t dest_port = 32768 + 666; /* starting port for the UDP probes */
155 static char *gw_list[MAXMAX_GWS];	/* list of gateways as user enters */
156 static int interval = 1;		/* interval between transmissions */
157 static int options;			/* socket options */
158 static int moptions;			/* multicast options */
159 int npackets;				/* number of packets to send */
160 static ushort_t tos;			/* type-of-service value */
161 static int hoplimit = -1;		/* time-to-live value */
162 static int dontfrag;			/* IP*_DONTFRAG */
163 static int timeout = TIMEOUT;		/* timeout value (sec) for probes */
164 static struct if_entry out_if;		/* interface argument */
165 int ident;				/* ID for this ping run */
166 static hrtime_t t_last_probe_sent;	/* the time we sent the last probe */
167 
168 /*
169  * This buffer stores the received packets. Currently it needs to be 32 bit
170  * aligned. In the future, we'll be using 64 bit alignment, so let's use 64 bit
171  * alignment now.
172  */
173 static uint64_t in_pkt[(IP_MAXPACKET + 1)/8];
174 
175 /* Used to store the ancillary data that comes with the received packets */
176 static uint64_t ancillary_data[(IP_MAXPACKET + 1)/8];
177 
178 static int ntransmitted;	/* number of packet sent to single IP address */
179 int nreceived;			/* # of packets we got back from target host */
180 int nreceived_last_target;	/* received from last target IP */
181 /*
182  * These are used for statistics. tmin is initialized to maximum longint value.
183  * The max value is also used for timeouts.   All times are in microseconds.
184  */
185 long long tmin = LLONG_MAX;
186 long long tmax;
187 int64_t tsum;			/* sum of all times, for doing average */
188 int64_t tsum2;			/* sum of squared times, for std. dev. */
189 
190 static struct targetaddr *build_targetaddr_list(struct addrinfo *,
191     union any_in_addr *);
192 extern void check_reply(struct addrinfo *, struct msghdr *, int, ushort_t);
193 extern void check_reply6(struct addrinfo *, struct msghdr *, int, ushort_t);
194 static struct targetaddr *create_targetaddr_item(int, union any_in_addr *,
195     union any_in_addr *);
196 void find_dstaddr(ushort_t, union any_in_addr *);
197 static struct ifaddrlist *find_if(struct ifaddrlist *, int);
198 static void finish();
199 static void get_gwaddrs(char *[], int, union any_in_addr *,
200     union any_in_addr *, int *, int *);
201 static void get_hostinfo(char *, int, struct addrinfo **);
202 static ushort_t in_cksum(ushort_t *, int);
203 static int int_arg(char *s, char *what);
204 boolean_t is_a_target(struct addrinfo *, union any_in_addr *);
205 static void mirror_gws(union any_in_addr *, int);
206 static void pinger(int, struct sockaddr *, struct msghdr *, int);
207 char *pr_name(char *, int);
208 char *pr_protocol(int);
209 static void print_unknown_host_msg(const char *, const char *);
210 static void recv_icmp_packet(struct addrinfo *, int, int, ushort_t, ushort_t);
211 static void resolve_nodes(struct addrinfo **, struct addrinfo **,
212     union any_in_addr **);
213 void schedule_sigalrm();
214 static void select_all_src_addrs(union any_in_addr **, struct addrinfo *,
215     union any_in_addr *, union any_in_addr *);
216 static void select_src_addr(union any_in_addr *, int, union any_in_addr *);
217 void send_scheduled_probe();
218 boolean_t seq_match(ushort_t, int, ushort_t);
219 extern void set_ancillary_data(struct msghdr *, int, union any_in_addr *, int,
220     uint_t);
221 extern void set_IPv4_options(int, union any_in_addr *, int, struct in_addr *,
222     struct in_addr *);
223 static void set_nexthop(int, struct addrinfo *, int);
224 static boolean_t setup_socket(int, int *, int *, int *, ushort_t *,
225     struct addrinfo *);
226 void sigalrm_handler();
227 void tvsub(struct timeval *, struct timeval *);
228 static void usage(char *);
229 
230 /*
231  * main()
232  */
233 int
234 main(int argc, char *argv[])
235 {
236 	struct addrinfo	*ai_dst = NULL;		/* addrinfo host list */
237 	struct addrinfo	*ai_nexthop = NULL;		/* addrinfo nexthop */
238 	union any_in_addr *src_addr_list = NULL;	/* src addrs to use */
239 	int recv_sock = -1;				/* receive sockets */
240 	int recv_sock6 = -1;
241 	ushort_t udp_src_port;			/* src ports for UDP probes */
242 	ushort_t udp_src_port6;			/* used to identify replies */
243 	uint_t flowinfo = 0;
244 	uint_t class = 0;
245 	char abuf[INET6_ADDRSTRLEN];
246 	int c;
247 	int i;
248 	boolean_t has_sys_ip_config;
249 
250 	progname = argv[0];
251 
252 	/*
253 	 * This program needs the net_icmpaccess privilege for creating
254 	 * raw ICMP sockets.  It needs sys_ip_config for using the
255 	 * IP_NEXTHOP socket option (IPv4 only).  We'll fail
256 	 * on the socket call and report the error there when we have
257 	 * insufficient privileges.
258 	 *
259 	 * Shared-IP zones don't have the sys_ip_config privilege, so
260 	 * we need to check for it in our limit set before trying
261 	 * to set it.
262 	 */
263 	has_sys_ip_config = priv_ineffect(PRIV_SYS_IP_CONFIG);
264 
265 	(void) __init_suid_priv(PU_CLEARLIMITSET, PRIV_NET_ICMPACCESS,
266 	    has_sys_ip_config ? PRIV_SYS_IP_CONFIG : (char *)NULL,
267 	    (char *)NULL);
268 
269 	setbuf(stdout, (char *)0);
270 
271 	while ((c = getopt(argc, argv,
272 	    "abA:c:dDF:G:g:I:i:LlnN:P:p:rRSsTt:UvX:x:Y0123?")) != -1) {
273 		switch ((char)c) {
274 		case 'A':
275 			if (strcmp(optarg, "inet") == 0) {
276 				family_input = AF_INET;
277 			} else if (strcmp(optarg, "inet6") == 0) {
278 				family_input = AF_INET6;
279 			} else {
280 				Fprintf(stderr,
281 				    "%s: unknown address family %s\n",
282 				    progname, optarg);
283 				exit(EXIT_FAILURE);
284 			}
285 			break;
286 
287 		case 'a':
288 			probe_all = _B_TRUE;
289 			break;
290 
291 		case 'c':
292 			i = int_arg(optarg, "traffic class");
293 			if (i > MAX_TRAFFIC_CLASS) {
294 				Fprintf(stderr, "%s: traffic class %d out of "
295 				    "range\n", progname, i);
296 				exit(EXIT_FAILURE);
297 			}
298 			class = (uint_t)i;
299 			break;
300 
301 		case 'd':
302 			options |= SO_DEBUG;
303 			break;
304 
305 		case 'D':
306 			dontfrag = 1;
307 			break;
308 
309 		case 'b':
310 			bypass = _B_TRUE;
311 			break;
312 
313 		case 'F':
314 			i = int_arg(optarg, "flow label");
315 			if (i > MAX_FLOW_LABEL) {
316 				Fprintf(stderr, "%s: flow label %d out of "
317 				    "range\n", progname, i);
318 				exit(EXIT_FAILURE);
319 			}
320 			flowinfo = (uint_t)i;
321 			break;
322 
323 		case 'I':
324 			stats = _B_TRUE;
325 			interval = int_arg(optarg, "interval");
326 			break;
327 
328 		case 'i':
329 			/*
330 			 * this can accept interface index, interface name, and
331 			 * address configured on the interface
332 			 */
333 			moptions |= MULTICAST_IF;
334 			out_if.str = optarg;
335 
336 			if (inet_pton(AF_INET6, optarg, &out_if.id.addr) > 0) {
337 				out_if.id_type = IF_ADDR6;
338 			} else if (inet_pton(AF_INET, optarg,
339 			    &out_if.id.addr) > 0) {
340 				out_if.id_type = IF_ADDR;
341 			} else if (strcmp(optarg, "0") == 0) {
342 				out_if.id_type = IF_INDEX;
343 				out_if.id.index = 0;
344 			} else if ((out_if.id.index = atoi(optarg)) != 0) {
345 				out_if.id_type = IF_INDEX;
346 			} else {
347 				out_if.id.name = optarg;
348 				out_if.id_type = IF_NAME;
349 			}
350 			break;
351 
352 		case 'L':
353 			moptions |= MULTICAST_NOLOOP;
354 			break;
355 
356 		case 'l':
357 			send_reply = _B_TRUE;
358 			strict = _B_FALSE;
359 			break;
360 
361 		case 'n':
362 			nflag = _B_TRUE;
363 			break;
364 
365 		case 'P':
366 			settos = _B_TRUE;
367 			i = int_arg(optarg, "type-of-service");
368 			if (i > MAX_TOS) {
369 				Fprintf(stderr, "%s: tos value %d out of "
370 				    "range\n", progname, i);
371 				exit(EXIT_FAILURE);
372 			}
373 			tos = (ushort_t)i;
374 			break;
375 
376 		case 'p':
377 			i = int_arg(optarg, "port number");
378 			if (i > MAX_PORT) {
379 				Fprintf(stderr, "%s: port number %d out of "
380 				    "range\n", progname, i);
381 				exit(EXIT_FAILURE);
382 			}
383 			dest_port = (ushort_t)i;
384 			break;
385 
386 		case 'r':
387 			options |= SO_DONTROUTE;
388 			break;
389 
390 		case 'R':
391 			rr_option = _B_TRUE;
392 			break;
393 
394 		case 'S':
395 			send_reply = _B_TRUE;
396 			strict = _B_TRUE;
397 			break;
398 
399 		case 's':
400 			stats = _B_TRUE;
401 			break;
402 
403 		case 'T':
404 			ts_option = _B_TRUE;
405 			break;
406 
407 		case 't':
408 			moptions |= MULTICAST_TTL;
409 			hoplimit = int_arg(optarg, "ttl");
410 			if (hoplimit > MAXTTL) {
411 				Fprintf(stderr, "%s: ttl %d out of range\n",
412 				    progname, hoplimit);
413 				exit(EXIT_FAILURE);
414 			}
415 			break;
416 
417 		case 'U':
418 			use_udp = _B_TRUE;
419 			use_icmp_ts = _B_FALSE;
420 			break;
421 
422 		case 'v':
423 			verbose = _B_TRUE;
424 			break;
425 		/*
426 		 * 'x' and 'X' has been undocumented flags for source routing.
427 		 * Now we document loose source routing with the new flag 'g',
428 		 * which is same as in traceroute. We still keep x/X as
429 		 * as undocumented. 'G', which is for strict source routing is
430 		 * also undocumented.
431 		 */
432 		case 'x':
433 		case 'g':
434 			strict = _B_FALSE;
435 			if (num_gw > MAXMAX_GWS) {
436 				Fprintf(stderr, "%s: too many gateways\n",
437 				    progname);
438 				exit(EXIT_FAILURE);
439 			}
440 			gw_list[num_gw++] = optarg;
441 			break;
442 
443 		case 'X':
444 		case 'G':
445 			strict = _B_TRUE;
446 			if (num_gw > MAXMAX_GWS) {
447 				Fprintf(stderr, "%s: too many gateways\n",
448 				    progname);
449 				exit(EXIT_FAILURE);
450 			}
451 			gw_list[num_gw++] = optarg;
452 			break;
453 
454 		case 'N':
455 			if (nexthop != NULL) {
456 				Fprintf(stderr, "%s: only one next hop gateway"
457 				    " allowed\n", progname);
458 				exit(EXIT_FAILURE);
459 			}
460 			nexthop = optarg;
461 			break;
462 
463 		case 'Y':
464 			use_icmp_ts = _B_TRUE;
465 			use_udp = _B_FALSE;
466 			break;
467 
468 		case '0':
469 		case '1':
470 		case '2':
471 		case '3':
472 			ts_flag = (char)c - '0';
473 			break;
474 
475 		case '?':
476 			usage(progname);
477 			exit(EXIT_FAILURE);
478 			break;
479 
480 		default:
481 			usage(progname);
482 			exit(EXIT_FAILURE);
483 			break;
484 		}
485 	}
486 
487 	if (optind >= argc) {
488 		usage(progname);
489 		exit(EXIT_FAILURE);
490 	}
491 
492 	/*
493 	 * send_reply, which sends the probe packet back to itself
494 	 * doesn't work with UDP
495 	 */
496 	if (use_udp)
497 		send_reply = _B_FALSE;
498 
499 	if (getenv("MACHINE_THAT_GOES_PING") != NULL)
500 		stats = _B_TRUE;
501 
502 	targethost = argv[optind];
503 	optind++;
504 	if (optind < argc) {
505 		if (stats) {
506 			datalen = int_arg(argv[optind], "data size");
507 			optind++;
508 			if (optind < argc) {
509 				npackets = int_arg(argv[optind],
510 				    "packet count");
511 				if (npackets < 1) {
512 					Fprintf(stderr, "%s: packet count %d "
513 					    "out of range\n", progname,
514 					    npackets);
515 					exit(EXIT_FAILURE);
516 				}
517 			}
518 		} else {
519 			timeout = int_arg(argv[optind], "timeout");
520 		}
521 	}
522 
523 	/*
524 	 * Let's prepare sockaddr_in* structures, cause we might need both of
525 	 * them.
526 	 */
527 	bzero((char *)&to, sizeof (struct sockaddr_in));
528 	to.sin_family = AF_INET;
529 
530 	bzero((char *)&to6, sizeof (struct sockaddr_in6));
531 	to6.sin6_family = AF_INET6;
532 	to6.sin6_flowinfo = htonl((class << 20) | flowinfo);
533 
534 	if (stats)
535 		(void) sigset(SIGINT, finish);
536 
537 	ident = (int)getpid() & 0xFFFF;
538 
539 	/* resolve the hostnames */
540 	resolve_nodes(&ai_dst, &ai_nexthop, &src_addr_list);
541 
542 	/*
543 	 * We should make sure datalen is reasonable.
544 	 * 	IP_MAXPACKET >= IPv4/IPv6 header length +
545 	 *			IPv4 options/IPv6 routing header length +
546 	 *			ICMP/ICMP6/UDP header length +
547 	 *			datalen
548 	 */
549 
550 	if (family_input == AF_INET6 ||
551 	    (family_input == AF_UNSPEC && num_v6 != 0)) {
552 		size_t exthdr_len = 0;
553 
554 		if (send_reply) {
555 			exthdr_len = sizeof (struct ip6_rthdr0) +
556 			    2 * num_gw * sizeof (struct in6_addr);
557 		} else if (num_gw > 0) {
558 			exthdr_len = sizeof (struct ip6_rthdr0) +
559 			    num_gw * sizeof (struct in6_addr);
560 		}
561 
562 		/*
563 		 * Size of ICMP6 header and UDP header are the same. Let's
564 		 * use ICMP6_MINLEN.
565 		 */
566 		if (datalen > (IP_MAXPACKET - (sizeof (struct ip6_hdr) +
567 		    exthdr_len + ICMP6_MINLEN))) {
568 			Fprintf(stderr,
569 			    "%s: data size too large for IPv6 packet\n",
570 			    progname);
571 			num_v6 = 0;
572 		}
573 	}
574 
575 	if (family_input == AF_INET ||
576 	    (family_input == AF_UNSPEC && num_v4 != 0)) {
577 		size_t opt_len = 0;
578 
579 		if (send_reply) {
580 			/*
581 			 * Includes 3 bytes code+ptr+len, the intermediate
582 			 * gateways, the actual and the effective target.
583 			 */
584 			opt_len = 3 +
585 			    (2 * num_gw + 2) * sizeof (struct in_addr);
586 		} else if (num_gw > 0) {
587 			opt_len = 3 + (num_gw + 1) * sizeof (struct in_addr);
588 		}
589 
590 		if (rr_option) {
591 			opt_len = MAX_IPOPTLEN;
592 		} else if (ts_option) {
593 			if ((ts_flag & 0x0f) <= IPOPT_TS_TSANDADDR) {
594 				opt_len = MAX_IPOPTLEN;
595 			} else {
596 				opt_len += IPOPT_MINOFF +
597 				    2 * sizeof (struct ipt_ta);
598 				/*
599 				 * Note: BSD/4.X is broken in their check so we
600 				 * have to  bump up this number by at least one.
601 				 */
602 				opt_len++;
603 			}
604 		}
605 
606 		/* Round up to 4 byte boundary */
607 		if (opt_len & 0x3)
608 			opt_len = (opt_len & ~0x3) + 4;
609 
610 		if (datalen > (IP_MAXPACKET - (sizeof (struct ip) + opt_len +
611 		    ICMP_MINLEN))) {
612 			Fprintf(stderr,
613 			    "%s: data size too large for IPv4 packet\n",
614 			    progname);
615 			num_v4 = 0;
616 		}
617 	}
618 
619 	if (num_v4 == 0 && num_v6 == 0) {
620 		exit(EXIT_FAILURE);
621 	}
622 
623 	/* setup the sockets */
624 	if (num_v6 != 0) {
625 		if (!setup_socket(AF_INET6, &send_sock6, &recv_sock6,
626 		    &if_index, &udp_src_port6, ai_nexthop))
627 			exit(EXIT_FAILURE);
628 	}
629 
630 	if (num_v4 != 0) {
631 		if (!setup_socket(AF_INET, &send_sock, &recv_sock, &if_index,
632 		    &udp_src_port, ai_nexthop))
633 			exit(EXIT_FAILURE);
634 	}
635 
636 	__priv_relinquish();
637 
638 	/*
639 	 * If sending back to ourself, add the mirror image of current
640 	 * gateways, so that the probes travel to and from the target
641 	 * by visiting the same gateways in reverse order.
642 	 */
643 	if (send_reply) {
644 		if (num_v6 != 0)
645 			mirror_gws(gw_IP_list6, AF_INET6);
646 		if (num_v4 != 0)
647 			mirror_gws(gw_IP_list, AF_INET);
648 
649 		/* We add 1 because we put the target as the middle gateway */
650 		eff_num_gw = 2 * num_gw + 1;
651 
652 	} else {
653 		eff_num_gw = num_gw;
654 	}
655 
656 	targetaddr_list = build_targetaddr_list(ai_dst, src_addr_list);
657 	current_targetaddr = targetaddr_list;
658 
659 	/*
660 	 * Set the starting_seq_num for the first targetaddr.
661 	 * If we are sending ICMP Echo Requests, the sequence number is same as
662 	 * ICMP sequence number, and it starts from zero. If we are sending UDP
663 	 * packets, the sequence number is the destination UDP port number,
664 	 * which starts from dest_port. At each probe, this sequence number is
665 	 * incremented by one.
666 	 * We set the starting_seq_num for first targetaddr here. The
667 	 * following ones will be set by looking at where we left with the last
668 	 * targetaddr.
669 	 */
670 	current_targetaddr->starting_seq_num = use_udp ? dest_port : 0;
671 
672 	if (stats) {
673 		if (probe_all || !nflag) {
674 			Printf("PING %s: %d data bytes\n", targethost, datalen);
675 		} else {
676 			if (ai_dst->ai_family == AF_INET) {
677 				(void) inet_ntop(AF_INET,
678 				    &((struct sockaddr_in *)(void *)
679 				    ai_dst->ai_addr)->sin_addr,
680 				    abuf, sizeof (abuf));
681 			} else {
682 				(void) inet_ntop(AF_INET6,
683 				    &((struct sockaddr_in6 *)(void *)
684 				    ai_dst->ai_addr)->sin6_addr,
685 				    abuf, sizeof (abuf));
686 			}
687 			Printf("PING %s (%s): %d data bytes\n",
688 			    targethost, abuf, datalen);
689 		}
690 	}
691 
692 	/* Let's get things going */
693 	send_scheduled_probe();
694 
695 	/* SIGALRM is used to send the next scheduled probe */
696 	(void) sigset(SIGALRM, sigalrm_handler);
697 	schedule_sigalrm();
698 
699 	/*
700 	 * From now on, we'll always be listening to ICMP packets. As SIGALRM
701 	 * comes in, sigalrm_handler() will be invoked and send another
702 	 * probe.
703 	 */
704 	recv_icmp_packet(ai_dst, recv_sock6, recv_sock, udp_src_port6,
705 	    udp_src_port);
706 
707 	return (EXIT_SUCCESS);	/* should never come here */
708 }
709 
710 /*
711  * Build the target IP address list. Use command line options and
712  * name lookup results returned from name server to determine which addresses
713  * to probe, how many times, in which order.
714  */
715 static struct targetaddr *
716 build_targetaddr_list(struct addrinfo *ai_dst, union any_in_addr *src_addr_list)
717 {
718 	struct targetaddr *head = NULL;
719 	struct targetaddr *targetaddr;
720 	struct targetaddr **nextp;
721 	int num_dst;
722 	int i;
723 	struct addrinfo *aip;
724 
725 	aip = ai_dst;
726 	if (probe_all)
727 		num_dst = num_v4 + num_v6;
728 	else
729 		num_dst = 1;
730 	num_targetaddrs = num_dst;
731 	nextp = &head;
732 	for (aip = ai_dst, i = 0; aip != NULL; aip = aip->ai_next, i++) {
733 		if (aip->ai_family == AF_INET && num_v4 != 0) {
734 			targetaddr = create_targetaddr_item(aip->ai_family,
735 			    (union any_in_addr *)
736 			    /* LINTED E_BAD_PTR_CAST_ALIGN */
737 			    &((struct sockaddr_in *)
738 			    aip->ai_addr)->sin_addr,
739 			    &src_addr_list[i]);
740 		} else if (aip->ai_family == AF_INET6 && num_v6 != 0) {
741 			targetaddr = create_targetaddr_item(aip->ai_family,
742 			    (union any_in_addr *)
743 			    /* LINTED E_BAD_PTR_CAST_ALIGN */
744 			    &((struct sockaddr_in6 *)
745 			    aip->ai_addr)->sin6_addr,
746 			    &src_addr_list[i]);
747 		} else {
748 			continue;
749 		}
750 		*nextp = targetaddr;
751 		nextp = &targetaddr->next;
752 		if (num_targetaddrs == 1)
753 			break;
754 	}
755 	if (npackets == 0 && stats)
756 		*nextp = head;	/* keep going indefinitely */
757 
758 	return (head);
759 }
760 
761 /*
762  * Given an address family, dst and src addresses, by also looking at the
763  * options provided at the command line, this function creates a targetaddr
764  * to be linked with others, forming a global targetaddr list. Each targetaddr
765  * item contains information about probes sent to a specific IP address.
766  */
767 static struct targetaddr *
768 create_targetaddr_item(int family, union any_in_addr *dst_addr,
769     union any_in_addr *src_addr)
770 {
771 	struct targetaddr *targetaddr;
772 
773 	targetaddr = (struct targetaddr *)malloc(sizeof (struct targetaddr));
774 	if (targetaddr == NULL) {
775 		Fprintf(stderr, "%s: malloc %s\n", progname, strerror(errno));
776 		exit(EXIT_FAILURE);
777 	}
778 	targetaddr->family = family;
779 	targetaddr->dst_addr = *dst_addr;
780 	targetaddr->src_addr = *src_addr;
781 	if (stats) {
782 		/*
783 		 * npackets is only defined if we are in stats mode.
784 		 * npackets determines how many probes to send to each target
785 		 * IP address. npackets == 0 means send only 1 and move on to
786 		 * next target IP.
787 		 */
788 		if (npackets > 0)
789 			targetaddr->num_probes = npackets;
790 		else
791 			targetaddr->num_probes = 1;
792 	} else {
793 		targetaddr->num_probes = timeout;
794 	}
795 	targetaddr->num_sent = 0;
796 	targetaddr->got_reply = _B_FALSE;
797 	targetaddr->probing_done = _B_FALSE;
798 	targetaddr->starting_seq_num = 0; /* actual value will be set later */
799 	targetaddr->next = NULL;	/* actual value will be set later */
800 
801 	return (targetaddr);
802 }
803 
804 /*
805  * print "unknown host" message
806  */
807 static void
808 print_unknown_host_msg(const char *protocol, const char *hostname)
809 {
810 	Fprintf(stderr, "%s: unknown%s host %s\n", progname, protocol,
811 	    hostname);
812 }
813 
814 /*
815  * Resolve hostnames for the target host and gateways. Also, determine source
816  * addresses to use for each target address.
817  */
818 static void
819 resolve_nodes(struct addrinfo **ai_dstp, struct addrinfo **ai_nexthopp,
820     union any_in_addr **src_addr_listp)
821 {
822 	struct addrinfo *ai_dst = NULL;
823 	struct addrinfo *ai_nexthop = NULL;
824 	struct addrinfo *aip = NULL;
825 	union any_in_addr *src_addr_list = NULL;
826 	int num_resolved_gw = 0;
827 	int num_resolved_gw6 = 0;
828 
829 	get_hostinfo(targethost, family_input, &ai_dst);
830 	if (ai_dst == NULL) {
831 		print_unknown_host_msg("", targethost);
832 		exit(EXIT_FAILURE);
833 	}
834 	if (nexthop != NULL) {
835 		get_hostinfo(nexthop, family_input, &ai_nexthop);
836 		if (ai_nexthop == NULL) {
837 			print_unknown_host_msg("", nexthop);
838 			exit(EXIT_FAILURE);
839 		}
840 	}
841 	/* Get a count of the v4 & v6 addresses */
842 	for (aip = ai_dst; aip != NULL; aip = aip->ai_next) {
843 		switch (aip->ai_family) {
844 		case AF_INET:
845 			num_v4++;
846 			break;
847 		case AF_INET6:
848 			num_v6++;
849 			break;
850 		}
851 	}
852 
853 	if (family_input == AF_UNSPEC && !probe_all) {
854 		family_input = ai_dst->ai_family;
855 	}
856 
857 	/* resolve gateways */
858 	if (num_gw > 0) {
859 		get_gwaddrs(gw_list, family_input, gw_IP_list, gw_IP_list6,
860 		    &num_resolved_gw, &num_resolved_gw6);
861 
862 		/* we couldn't resolve a gateway as an IPv6 host */
863 		if (num_resolved_gw6 != num_gw && num_v6 != 0 &&
864 		    (family_input == AF_INET6 || family_input == AF_UNSPEC)) {
865 			print_unknown_host_msg(" IPv6",
866 			    gw_list[num_resolved_gw6]);
867 			num_v6 = 0;
868 		}
869 
870 		/* we couldn't resolve a gateway as an IPv4 host */
871 		if (num_resolved_gw != num_gw && num_v4 != 0 &&
872 		    (family_input == AF_INET || family_input == AF_UNSPEC)) {
873 			print_unknown_host_msg(" IPv4",
874 			    gw_list[num_resolved_gw]);
875 			num_v4 = 0;
876 		}
877 	}
878 
879 	if (num_v4 == 0 && num_v6 == 0)
880 		exit(EXIT_FAILURE);
881 
882 	select_all_src_addrs(&src_addr_list, ai_dst, gw_IP_list, gw_IP_list6);
883 	*ai_dstp = ai_dst;
884 	*ai_nexthopp = ai_nexthop;
885 	*src_addr_listp = src_addr_list;
886 }
887 
888 /*
889  * Resolve the gateway names, splitting results into v4 and v6 lists.
890  * Gateway addresses are added to the appropriate passed-in array; the
891  * number of resolved gateways for each af is returned in resolved[6].
892  * Assumes that passed-in arrays are large enough for MAX_GWS[6] addrs
893  * and resolved[6] ptrs are non-null; ignores array and counter if the
894  * address family param makes them irrelevant.
895  */
896 static void
897 get_gwaddrs(char **gw_list, int family, union any_in_addr *gwIPlist,
898     union any_in_addr *gwIPlist6, int *resolved, int *resolved6)
899 {
900 	int i;
901 	boolean_t check_v4 = _B_TRUE, check_v6 = _B_TRUE;
902 	struct addrinfo	*ai = NULL;
903 	struct addrinfo	*aip = NULL;
904 
905 	*resolved = *resolved6 = 0;
906 	switch (family) {
907 	case AF_UNSPEC:
908 		break;
909 	case AF_INET:
910 		check_v6 = _B_FALSE;
911 		break;
912 	case AF_INET6:
913 		check_v4 = _B_FALSE;
914 		break;
915 	default:
916 		return;
917 	}
918 
919 	if (check_v4 && num_gw >= MAX_GWS) {
920 		check_v4 = _B_FALSE;
921 		Fprintf(stderr, "%s: too many IPv4 gateways\n", progname);
922 	}
923 	if (check_v6 && num_gw > MAX_GWS6) {
924 		check_v6 = _B_FALSE;
925 		Fprintf(stderr, "%s: too many IPv6 gateways\n", progname);
926 	}
927 
928 	for (i = 0; i < num_gw; i++) {
929 		if (!check_v4 && !check_v6)
930 			return;
931 		get_hostinfo(gw_list[i], family, &ai);
932 		if (ai == NULL)
933 			return;
934 		if (check_v4 && num_v4 != 0) {
935 			for (aip = ai; aip != NULL; aip = aip->ai_next) {
936 				if (aip->ai_family == AF_INET) {
937 					/* LINTED E_BAD_PTR_CAST_ALIGN */
938 					bcopy(&((struct sockaddr_in *)
939 					    aip->ai_addr)->sin_addr,
940 					    &gwIPlist[i].addr,
941 					    aip->ai_addrlen);
942 					(*resolved)++;
943 					break;
944 				}
945 			}
946 		} else if (check_v4) {
947 			check_v4 = _B_FALSE;
948 		}
949 		if (check_v6 && num_v6 != 0) {
950 			for (aip = ai; aip != NULL; aip = aip->ai_next) {
951 				if (aip->ai_family == AF_INET6) {
952 					/* LINTED E_BAD_PTR_CAST_ALIGN */
953 					bcopy(&((struct sockaddr_in6 *)
954 					    aip->ai_addr)->sin6_addr,
955 					    &gwIPlist6[i].addr6,
956 					    aip->ai_addrlen);
957 					(*resolved6)++;
958 					break;
959 				}
960 			}
961 		} else if (check_v6) {
962 			check_v6 = _B_FALSE;
963 		}
964 	}
965 	freeaddrinfo(ai);
966 }
967 
968 /*
969  * Given the list of gateways, extends the list with its mirror image. This is
970  * used when -l/-S is used. The middle gateway will be the target address. We'll
971  * leave it blank for now.
972  */
973 static void
974 mirror_gws(union any_in_addr *gwIPlist, int family)
975 {
976 	int effective_num_gw;
977 	int i;
978 
979 	/* We add 1 because we put the target as the middle gateway */
980 	effective_num_gw = 2 * num_gw + 1;
981 
982 	if ((family == AF_INET && effective_num_gw >= MAX_GWS) ||
983 	    (family == AF_INET6 && effective_num_gw > MAX_GWS6)) {
984 		Fprintf(stderr, "%s: too many %s gateways\n",
985 		    progname, (family == AF_INET) ? "IPv4" : "IPv6");
986 		exit(EXIT_FAILURE);
987 	}
988 
989 	for (i = 0; i < num_gw; i++)
990 		gwIPlist[num_gw + i + 1].addr6 = gwIPlist[num_gw - i - 1].addr6;
991 }
992 
993 /*
994  * Given IP address or hostname, return addrinfo list.
995  * Assumes that addrinfo ** ptr is non-null.
996  */
997 static void
998 get_hostinfo(char *host, int family, struct addrinfo **aipp)
999 {
1000 	struct addrinfo hints, *ai;
1001 	struct in6_addr addr6;
1002 	struct in_addr addr;
1003 	boolean_t broadcast;		/* is this 255.255.255.255? */
1004 	char tmp_buf[INET6_ADDRSTRLEN];
1005 	int rc;
1006 
1007 	/* check if broadcast */
1008 	if (strcmp(host, "255.255.255.255") == 0)
1009 		broadcast = _B_TRUE;
1010 	else
1011 		broadcast = _B_FALSE;
1012 
1013 	/* check if IPv4-mapped address or broadcast */
1014 	if (((inet_pton(AF_INET6, host, &addr6) > 0) &&
1015 	    IN6_IS_ADDR_V4MAPPED(&addr6)) || broadcast) {
1016 		if (!broadcast) {
1017 			/*
1018 			 * Peel off the "mapping" stuff, leaving 32 bit IPv4
1019 			 * address.
1020 			 */
1021 			IN6_V4MAPPED_TO_INADDR(&addr6, &addr);
1022 
1023 			/* convert it back to a string */
1024 			(void) inet_ntop(AF_INET, (void *)&addr, tmp_buf,
1025 			    sizeof (tmp_buf));
1026 			/*
1027 			 * Now the host is an IPv4 address.
1028 			 * Since it previously was a v4 mapped v6 address
1029 			 * we can be sure that the size of buffer 'host'
1030 			 * is large enough to contain the associated v4
1031 			 * address and so we don't need to use a strn/lcpy
1032 			 * here.
1033 			 */
1034 			(void) strcpy(host, tmp_buf);
1035 		}
1036 		/*
1037 		 * If it's a broadcast address, it cannot be an IPv6 address.
1038 		 * Also, if it's a mapped address, we convert it into IPv4
1039 		 * address because ping will send and receive IPv4 packets for
1040 		 * that address. Therefore, it's a failure case to ask
1041 		 * get_hostinfo() to treat a broadcast or a mapped address
1042 		 * as an IPv6 address.
1043 		 */
1044 		if (family == AF_INET6) {
1045 			return;
1046 		}
1047 	}
1048 
1049 	(void) memset(&hints, 0, sizeof (hints));
1050 	hints.ai_family = family;
1051 	hints.ai_flags = AI_ADDRCONFIG;
1052 	rc = getaddrinfo(host, NULL, &hints, &ai);
1053 	if (rc != 0) {
1054 		if (rc != EAI_NONAME)
1055 			Fprintf(stderr, "%s: getaddrinfo: %s\n", progname,
1056 			    gai_strerror(rc));
1057 		return;
1058 	}
1059 	*aipp = ai;
1060 }
1061 
1062 /*
1063  * For each IP address of the target host, determine a source address to use.
1064  */
1065 static void
1066 select_all_src_addrs(union any_in_addr **src_addr_list, struct addrinfo *ai,
1067     union any_in_addr *gwv4, union any_in_addr *gwv6)
1068 {
1069 	union any_in_addr *list;
1070 	struct addrinfo *aip;
1071 	int num_dst = 1;
1072 	int i;
1073 
1074 	if (probe_all) {
1075 		for (aip = ai; aip->ai_next != NULL; aip = aip->ai_next)
1076 			num_dst++;
1077 	}
1078 
1079 	list = calloc((size_t)num_dst, sizeof (union any_in_addr));
1080 	if (list == NULL) {
1081 		Fprintf(stderr, "%s: calloc: %s\n", progname, strerror(errno));
1082 		exit(EXIT_FAILURE);
1083 	}
1084 
1085 	/*
1086 	 * If there's a gateway, a routing header as a consequence, our kernel
1087 	 * picks the source address based on the first hop address, rather than
1088 	 * final destination address.
1089 	 */
1090 	if (num_gw > 0) {
1091 		if (ai->ai_family == AF_INET)
1092 			select_src_addr(gwv4, ai->ai_family, &list[0]);
1093 		else
1094 			select_src_addr(gwv6, ai->ai_family, &list[0]);
1095 		/*
1096 		 * Since the first gateway address is fixed, we'll use the same
1097 		 * src address for every different final destination address
1098 		 * we send to.
1099 		 */
1100 		for (i = 1; i < num_dst; i++)
1101 			list[i] = list[0];
1102 	} else {
1103 		/*
1104 		 * Although something like 'ping -l host' results in a routing
1105 		 * header, the first gateway address is the target host's
1106 		 * address. Therefore, as far as src address selection goes,
1107 		 * the result is same as having no routing header.
1108 		 */
1109 		for (i = 0, aip = ai; i < num_dst && aip != NULL;
1110 		    i++, aip = aip->ai_next) {
1111 			if (aip->ai_family == AF_INET) {
1112 				if (num_v4 != 0) {
1113 					select_src_addr((union any_in_addr *)
1114 					    /* LINTED E_BAD_PTR_CAST_ALIGN */
1115 					    &((struct sockaddr_in *)
1116 					    aip->ai_addr)->sin_addr,
1117 					    aip->ai_family,
1118 					    &list[i]);
1119 				}
1120 			} else {
1121 				if (num_v6 != 0) {
1122 					select_src_addr((union any_in_addr *)
1123 					    /* LINTED E_BAD_PTR_CAST_ALIGN */
1124 					    &((struct sockaddr_in6 *)
1125 					    aip->ai_addr)->sin6_addr,
1126 					    aip->ai_family,
1127 					    &list[i]);
1128 				}
1129 			}
1130 		}
1131 	}
1132 
1133 	*src_addr_list = list;
1134 }
1135 
1136 /*
1137  * For a given destination address, determine a source address to use.
1138  * Returns wildcard address if it cannot determine the source address.
1139  */
1140 static void
1141 select_src_addr(union any_in_addr *dst_addr, int family,
1142     union any_in_addr *src_addr)
1143 {
1144 	struct sockaddr *sock;
1145 	struct sockaddr_in *sin;
1146 	struct sockaddr_in6 *sin6;
1147 	int tmp_fd;
1148 	size_t sock_len;
1149 
1150 	sock = (struct sockaddr *)malloc(sizeof (struct sockaddr_in6));
1151 	if (sock == NULL) {
1152 		Fprintf(stderr, "%s: malloc: %s\n", progname, strerror(errno));
1153 		exit(EXIT_FAILURE);
1154 	}
1155 	(void) bzero(sock, sizeof (struct sockaddr_in6));
1156 
1157 	if (family == AF_INET) {
1158 		/* LINTED E_BAD_PTR_CAST_ALIGN */
1159 		sin = (struct sockaddr_in *)sock;
1160 		sin->sin_family = AF_INET;
1161 		sin->sin_addr = dst_addr->addr;
1162 		sin->sin_port = IPPORT_ECHO;	/* port shouldn't be 0 */
1163 		sock_len = sizeof (struct sockaddr_in);
1164 	} else {
1165 		/* LINTED E_BAD_PTR_CAST_ALIGN */
1166 		sin6 = (struct sockaddr_in6 *)sock;
1167 		sin6->sin6_family = AF_INET6;
1168 		sin6->sin6_addr = dst_addr->addr6;
1169 		sin6->sin6_port = IPPORT_ECHO;	/* port shouldn't be 0 */
1170 		sock_len = sizeof (struct sockaddr_in6);
1171 	}
1172 
1173 	/* open a UDP socket */
1174 	if ((tmp_fd = socket(family, SOCK_DGRAM, 0)) < 0) {
1175 		Fprintf(stderr, "%s: udp socket: %s\n", progname,
1176 		    strerror(errno));
1177 		exit(EXIT_FAILURE);
1178 	}
1179 
1180 	/* connect it */
1181 	if (connect(tmp_fd, sock, sock_len) < 0) {
1182 		/*
1183 		 * If there's no route to the destination, this connect() call
1184 		 * fails. We just return all-zero (wildcard) as the source
1185 		 * address, so that user can get to see "no route to dest"
1186 		 * message, as it'll try to send the probe packet out and will
1187 		 * receive ICMP unreachable.
1188 		 */
1189 		if (family == AF_INET)
1190 			src_addr->addr.s_addr = INADDR_ANY;
1191 		else
1192 			src_addr->addr6 = in6addr_any;
1193 		free(sock);
1194 		return;
1195 	}
1196 
1197 	/* get the local sock info */
1198 	if (getsockname(tmp_fd, sock, &sock_len) < 0) {
1199 		Fprintf(stderr, "%s: getsockname: %s\n", progname,
1200 		    strerror(errno));
1201 		exit(EXIT_FAILURE);
1202 	}
1203 
1204 	if (family == AF_INET) {
1205 		src_addr->addr = sin->sin_addr;
1206 	} else {
1207 		src_addr->addr6 = sin6->sin6_addr;
1208 	}
1209 
1210 	(void) close(tmp_fd);
1211 	free(sock);
1212 }
1213 
1214 /*
1215  * Set the IP_NEXTHOP/IPV6_NEXTHOP socket option.
1216  * exits on failure
1217  */
1218 static void
1219 set_nexthop(int family, struct addrinfo	*ai_nexthop, int sock)
1220 {
1221 	if (family == AF_INET) {
1222 		ipaddr_t nh;
1223 
1224 		/* LINTED E_BAD_PTR_CAST_ALIGN */
1225 		nh = ((struct sockaddr_in *)ai_nexthop->
1226 		    ai_addr)->sin_addr.s_addr;
1227 
1228 		/* now we need the sys_ip_config privilege */
1229 		(void) __priv_bracket(PRIV_ON);
1230 		if (setsockopt(sock, IPPROTO_IP, IP_NEXTHOP,
1231 		    &nh, sizeof (ipaddr_t)) < 0) {
1232 			if (errno == EPERM)
1233 				Fprintf(stderr, "%s: Insufficient privilege "
1234 				    "to specify IPv4 nexthop router.\n",
1235 				    progname);
1236 			else
1237 				Fprintf(stderr, "%s: setsockopt %s\n",
1238 				    progname, strerror(errno));
1239 			exit(EXIT_FAILURE);
1240 		}
1241 		(void) __priv_bracket(PRIV_OFF);
1242 		/* revert to non-privileged user */
1243 	} else {
1244 		struct sockaddr_in6 *nh;
1245 
1246 		/* LINTED E_BAD_PTR_CAST_ALIGN */
1247 		nh = (struct sockaddr_in6 *)ai_nexthop->
1248 		    ai_addr;
1249 
1250 		if (setsockopt(sock, IPPROTO_IPV6, IPV6_NEXTHOP,
1251 		    nh, sizeof (struct sockaddr_in6)) < 0) {
1252 			Fprintf(stderr, "%s: setsockopt %s\n",
1253 			    progname, strerror(errno));
1254 			exit(EXIT_FAILURE);
1255 		}
1256 	}
1257 }
1258 
1259 /*
1260  * Setup the socket for the given address family.
1261  * Returns _B_TRUE on success, _B_FALSE on failure. Failure is the case when no
1262  * interface can be found, or the specified interface (-i) is not found. On
1263  * library call failures, it exit()s.
1264  */
1265 static boolean_t
1266 setup_socket(int family, int *send_sockp, int *recv_sockp, int *if_index,
1267     ushort_t *udp_src_port, struct addrinfo *ai_nexthop)
1268 {
1269 	int send_sock;
1270 	int recv_sock;
1271 	struct sockaddr_in6 sin6;
1272 	struct sockaddr_in sin;
1273 	struct sockaddr *sp;
1274 	struct ipsec_req req;
1275 	size_t slen;
1276 	int on = 1;
1277 	uchar_t char_op;
1278 	int int_op;
1279 
1280 	/* now we need the net_icmpaccess privilege */
1281 	(void) __priv_bracket(PRIV_ON);
1282 
1283 	recv_sock = socket(family, SOCK_RAW,
1284 	    (family == AF_INET) ? IPPROTO_ICMP : IPPROTO_ICMPV6);
1285 
1286 	if (recv_sock < 0) {
1287 		Fprintf(stderr, "%s: socket %s\n", progname, strerror(errno));
1288 		exit(EXIT_FAILURE);
1289 	}
1290 
1291 	/* revert to non-privileged user after opening sockets */
1292 	(void) __priv_bracket(PRIV_OFF);
1293 
1294 	if (bypass) {
1295 		(void) memset(&req, 0, sizeof (req));
1296 		req.ipsr_ah_req = IPSEC_PREF_NEVER;
1297 		req.ipsr_esp_req = IPSEC_PREF_NEVER;
1298 
1299 		if (setsockopt(recv_sock, (family == AF_INET) ? IPPROTO_IP :
1300 		    IPPROTO_IPV6, IP_SEC_OPT, &req, sizeof (req)) < 0) {
1301 			switch (errno) {
1302 			case EPROTONOSUPPORT:
1303 				/*
1304 				 * No IPsec subsystem or policy loaded.
1305 				 * Bypass implicitly allowed.
1306 				 */
1307 				break;
1308 			case EPERM:
1309 				Fprintf(stderr, "%s: Insufficient privilege "
1310 				    "to bypass IPsec policy.\n", progname);
1311 				exit(EXIT_FAILURE);
1312 				break;
1313 			default:
1314 				Fprintf(stderr, "%s: setsockopt %s\n", progname,
1315 				    strerror(errno));
1316 				exit(EXIT_FAILURE);
1317 				break;
1318 			}
1319 		}
1320 	}
1321 
1322 	/*
1323 	 * We always receive on raw icmp socket. But the sending socket can be
1324 	 * raw icmp or udp, depending on the use of -U flag.
1325 	 */
1326 	if (use_udp) {
1327 		send_sock = socket(family, SOCK_DGRAM, IPPROTO_UDP);
1328 		if (send_sock < 0) {
1329 			Fprintf(stderr, "%s: socket %s\n", progname,
1330 			    strerror(errno));
1331 			exit(EXIT_FAILURE);
1332 		}
1333 
1334 		if (bypass) {
1335 			if (setsockopt(send_sock, (family == AF_INET) ?
1336 			    IPPROTO_IP : IPPROTO_IPV6, IP_SEC_OPT, &req,
1337 			    sizeof (req)) < 0) {
1338 				switch (errno) {
1339 				case EPROTONOSUPPORT:
1340 					/*
1341 					 * No IPsec subsystem or policy loaded.
1342 					 * Bypass implicitly allowed.
1343 					 */
1344 					break;
1345 				case EPERM:
1346 					Fprintf(stderr, "%s: Insufficient "
1347 					    "privilege to bypass IPsec "
1348 					    "policy.\n", progname);
1349 					exit(EXIT_FAILURE);
1350 					break;
1351 				default:
1352 					Fprintf(stderr, "%s: setsockopt %s\n",
1353 					    progname, strerror(errno));
1354 					exit(EXIT_FAILURE);
1355 					break;
1356 				}
1357 			}
1358 		}
1359 
1360 		/*
1361 		 * In order to distinguish replies to our UDP probes from
1362 		 * other pings', we need to know our source port number.
1363 		 */
1364 		if (family == AF_INET) {
1365 			sp = (struct sockaddr *)&sin;
1366 			slen = sizeof (sin);
1367 		} else {
1368 			sp = (struct sockaddr *)&sin6;
1369 			slen = sizeof (sin6);
1370 		}
1371 		bzero(sp, slen);
1372 		sp->sa_family = family;
1373 
1374 		/* Let's bind() send_sock to wildcard address and port */
1375 		if (bind(send_sock, sp, slen) < 0) {
1376 			Fprintf(stderr, "%s: bind %s\n", progname,
1377 			    strerror(errno));
1378 			exit(EXIT_FAILURE);
1379 		}
1380 
1381 		/* .... and see what port kernel picked for us */
1382 		if (getsockname(send_sock, sp, &slen) < 0) {
1383 			Fprintf(stderr, "%s: getsockname %s\n", progname,
1384 			    strerror(errno));
1385 			exit(EXIT_FAILURE);
1386 		}
1387 		*udp_src_port = (family == AF_INET) ? sin.sin_port :
1388 		    sin6.sin6_port;
1389 	} else {
1390 		send_sock = recv_sock;
1391 	}
1392 
1393 	if (nexthop != NULL)
1394 		set_nexthop(family, ai_nexthop, send_sock);
1395 
1396 	int_op = 48 * 1024;
1397 	if (int_op < datalen)
1398 		int_op = datalen;
1399 	if (setsockopt(recv_sock, SOL_SOCKET, SO_RCVBUF, (char *)&int_op,
1400 	    sizeof (int_op)) == -1) {
1401 		Fprintf(stderr, "%s: setsockopt SO_RCVBUF %s\n", progname,
1402 		    strerror(errno));
1403 		exit(EXIT_FAILURE);
1404 	}
1405 
1406 	if (setsockopt(send_sock, SOL_SOCKET, SO_SNDBUF, (char *)&int_op,
1407 	    sizeof (int_op)) == -1) {
1408 		Fprintf(stderr, "%s: setsockopt SO_SNDBUF %s\n", progname,
1409 		    strerror(errno));
1410 		exit(EXIT_FAILURE);
1411 	}
1412 
1413 	if (options & SO_DEBUG) {
1414 		if (setsockopt(send_sock, SOL_SOCKET, SO_DEBUG, (char *)&on,
1415 		    sizeof (on)) == -1) {
1416 			Fprintf(stderr, "%s: setsockopt SO_DEBUG %s\n",
1417 			    progname, strerror(errno));
1418 			exit(EXIT_FAILURE);
1419 		}
1420 	}
1421 
1422 	if (options & SO_DONTROUTE) {
1423 		if (setsockopt(send_sock, SOL_SOCKET, SO_DONTROUTE, (char *)&on,
1424 		    sizeof (on)) == -1) {
1425 			Fprintf(stderr, "%s: setsockopt SO_DONTROUTE %s\n",
1426 			    progname, strerror(errno));
1427 			exit(EXIT_FAILURE);
1428 		}
1429 	}
1430 
1431 	if (moptions & MULTICAST_NOLOOP) {
1432 		if (family == AF_INET) {
1433 			char_op = 0;	/* used to turn off option */
1434 
1435 			if (setsockopt(send_sock, IPPROTO_IP, IP_MULTICAST_LOOP,
1436 			    (char *)&char_op, sizeof (char_op)) == -1) {
1437 				Fprintf(stderr, "%s: setsockopt "
1438 				    "IP_MULTICAST_NOLOOP %s\n", progname,
1439 				    strerror(errno));
1440 				exit(EXIT_FAILURE);
1441 			}
1442 		} else {
1443 			int_op = 0;	/* used to turn off option */
1444 
1445 			if (setsockopt(send_sock, IPPROTO_IPV6,
1446 			    IPV6_MULTICAST_LOOP, (char *)&int_op,
1447 			    sizeof (int_op)) == -1) {
1448 				Fprintf(stderr, "%s: setsockopt "
1449 				    "IPV6_MULTICAST_NOLOOP %s\n", progname,
1450 				    strerror(errno));
1451 				exit(EXIT_FAILURE);
1452 			}
1453 		}
1454 	}
1455 
1456 	if (moptions & MULTICAST_TTL) {
1457 		char_op = hoplimit;
1458 
1459 		/* Applies to unicast and multicast. */
1460 		if (family == AF_INET) {
1461 			if (setsockopt(send_sock, IPPROTO_IP, IP_MULTICAST_TTL,
1462 			    (char *)&char_op, sizeof (char)) == -1) {
1463 				Fprintf(stderr, "%s: setsockopt "
1464 				    "IP_MULTICAST_TTL %s\n", progname,
1465 				    strerror(errno));
1466 				exit(EXIT_FAILURE);
1467 			}
1468 			if (setsockopt(send_sock, IPPROTO_IP, IP_TTL,
1469 			    (char *)&hoplimit, sizeof (hoplimit)) == -1) {
1470 				Fprintf(stderr, "%s: setsockopt IP_TTL %s\n",
1471 				    progname, strerror(errno));
1472 				exit(EXIT_FAILURE);
1473 			}
1474 		}
1475 		/*
1476 		 * AF_INET6 case is handled in set_ancillary_data() function.
1477 		 * This is because when ancillary data is used (for routing
1478 		 * header and outgoing interface index), the hoplimit set using
1479 		 * setsockopt() is ignored.
1480 		 */
1481 	}
1482 
1483 	/*
1484 	 * did the user specify an interface?
1485 	 * Applies to unicast, broadcast and multicast.
1486 	 */
1487 	if (moptions & MULTICAST_IF) {
1488 		struct ifaddrlist *al = NULL;		/* interface list */
1489 		struct ifaddrlist *my_if;
1490 		char errbuf[ERRBUFSIZE];
1491 		int num_ifs;
1492 		int num_src_ifs;		/* exclude down and loopback */
1493 		int i;
1494 
1495 		/* pull out the interface list */
1496 		num_ifs = ifaddrlist(&al, family, LIFC_UNDER_IPMP, errbuf);
1497 		if (num_ifs == -1) {
1498 			Fprintf(stderr, "%s: %s\n", progname, errbuf);
1499 			exit(EXIT_FAILURE);
1500 		}
1501 
1502 		/* filter out down and loopback interfaces */
1503 		num_src_ifs = 0;
1504 		for (i = 0; i < num_ifs; i++) {
1505 			if (!(al[i].flags & IFF_LOOPBACK) &&
1506 			    (al[i].flags & IFF_UP))
1507 				num_src_ifs++;
1508 		}
1509 
1510 		if (num_src_ifs == 0) {
1511 			Fprintf(stderr, "%s: can't find any %s interface\n",
1512 			    progname, (family == AF_INET) ? "IPv4" : "IPv6");
1513 
1514 			return (_B_FALSE);	/* failure */
1515 		}
1516 
1517 		/* locate the specified interface */
1518 		my_if = find_if(al, num_ifs);
1519 		if (my_if == NULL) {
1520 			Fprintf(stderr, "%s: %s is an invalid %s interface\n",
1521 			    progname, out_if.str,
1522 			    (family == AF_INET) ? "IPv4" : "IPv6");
1523 
1524 			return (_B_FALSE);
1525 		}
1526 
1527 		if (family == AF_INET) {
1528 			struct in_pktinfo pktinfo;
1529 
1530 			if (setsockopt(send_sock, IPPROTO_IP, IP_MULTICAST_IF,
1531 			    (char *)&my_if->addr.addr,
1532 			    sizeof (struct in_addr)) == -1) {
1533 				Fprintf(stderr, "%s: setsockopt "
1534 				    "IP_MULTICAST_IF %s\n", progname,
1535 				    strerror(errno));
1536 				exit(EXIT_FAILURE);
1537 			}
1538 			bzero(&pktinfo, sizeof (pktinfo));
1539 			pktinfo.ipi_ifindex = my_if->index;
1540 			if (setsockopt(send_sock, IPPROTO_IP, IP_PKTINFO,
1541 			    (char *)&pktinfo, sizeof (pktinfo)) == -1) {
1542 				Fprintf(stderr, "%s: setsockopt "
1543 				    "IP_PKTINFO %s\n", progname,
1544 				    strerror(errno));
1545 				exit(EXIT_FAILURE);
1546 			}
1547 		} else {
1548 			/*
1549 			 * the outgoing interface is set in set_ancillary_data()
1550 			 * function
1551 			 */
1552 			*if_index = my_if->index;
1553 		}
1554 
1555 		free(al);
1556 	}
1557 
1558 	if (settos && family == AF_INET) {
1559 		int_op = tos;
1560 		if (setsockopt(send_sock, IPPROTO_IP, IP_TOS, (char *)&int_op,
1561 		    sizeof (int_op)) == -1) {
1562 			Fprintf(stderr, "%s: setsockopt IP_TOS %s\n",
1563 			    progname, strerror(errno));
1564 			exit(EXIT_FAILURE);
1565 		}
1566 	}
1567 
1568 	/* We enable or disable to not depend on the kernel default */
1569 	if (family == AF_INET) {
1570 		if (setsockopt(send_sock, IPPROTO_IP, IP_DONTFRAG,
1571 		    (char *)&dontfrag, sizeof (dontfrag)) == -1) {
1572 			Fprintf(stderr, "%s: setsockopt IP_DONTFRAG %s\n",
1573 			    progname, strerror(errno));
1574 			exit(EXIT_FAILURE);
1575 		}
1576 	} else {
1577 		if (setsockopt(send_sock, IPPROTO_IPV6, IPV6_DONTFRAG,
1578 		    (char *)&dontfrag, sizeof (dontfrag)) == -1) {
1579 			Fprintf(stderr, "%s: setsockopt IPV6_DONTFRAG %s\n",
1580 			    progname, strerror(errno));
1581 			exit(EXIT_FAILURE);
1582 		}
1583 	}
1584 
1585 	/* receiving IPv6 extension headers in verbose mode */
1586 	if (verbose && family == AF_INET6) {
1587 		if (setsockopt(recv_sock, IPPROTO_IPV6, IPV6_RECVHOPOPTS,
1588 		    (char *)&on, sizeof (on)) == -1) {
1589 			Fprintf(stderr, "%s: setsockopt IPV6_RECVHOPOPTS %s\n",
1590 			    progname, strerror(errno));
1591 			exit(EXIT_FAILURE);
1592 		}
1593 
1594 		if (setsockopt(recv_sock, IPPROTO_IPV6, IPV6_RECVDSTOPTS,
1595 		    (char *)&on, sizeof (on)) == -1) {
1596 			Fprintf(stderr, "%s: setsockopt IPV6_RECVDSTOPTS %s\n",
1597 			    progname, strerror(errno));
1598 			exit(EXIT_FAILURE);
1599 		}
1600 
1601 		if (setsockopt(recv_sock, IPPROTO_IPV6, IPV6_RECVRTHDR,
1602 		    (char *)&on, sizeof (on)) == -1) {
1603 			Fprintf(stderr, "%s: setsockopt IPV6_RECVRTHDR %s\n",
1604 			    progname, strerror(errno));
1605 			exit(EXIT_FAILURE);
1606 		}
1607 	}
1608 
1609 	*send_sockp = send_sock;
1610 	*recv_sockp = recv_sock;
1611 
1612 	/* successful */
1613 	return (_B_TRUE);
1614 }
1615 
1616 /*
1617  * Pull out the record containing all the info about the interface specified by
1618  * `out_if'. Skips interfaces which are down or loopback.
1619  */
1620 static struct ifaddrlist *
1621 find_if(struct ifaddrlist *al, int num_ifs)
1622 {
1623 	static struct ifaddrlist tmp_if;
1624 	boolean_t found;
1625 	int i;
1626 
1627 	i = 0;
1628 	found = _B_FALSE;
1629 
1630 	while (i < num_ifs && !found) {
1631 		tmp_if = al[i];
1632 
1633 		/* skip down or loopback interfaces */
1634 		if ((tmp_if.flags & IFF_LOOPBACK) || !(tmp_if.flags & IFF_UP)) {
1635 			i++;
1636 			continue;
1637 		}
1638 
1639 		/* the type of interface id is variable */
1640 		switch (out_if.id_type) {
1641 		case IF_INDEX:
1642 			if (out_if.id.index == tmp_if.index)
1643 				found = _B_TRUE;
1644 			break;
1645 
1646 		case IF_NAME:
1647 			if (strcmp(out_if.id.name, tmp_if.device) == 0)
1648 				found = _B_TRUE;
1649 			break;
1650 
1651 		case IF_ADDR:
1652 			if (out_if.id.addr.addr.s_addr ==
1653 			    tmp_if.addr.addr.s_addr) {
1654 				found = _B_TRUE;
1655 			}
1656 			break;
1657 
1658 		case IF_ADDR6:
1659 			if (IN6_ARE_ADDR_EQUAL(&out_if.id.addr.addr6,
1660 			    &tmp_if.addr.addr6)) {
1661 				found = _B_TRUE;
1662 			}
1663 			break;
1664 
1665 		default:
1666 			break;
1667 		}
1668 
1669 		i++;
1670 	}
1671 
1672 	if (found)
1673 		return (&tmp_if);
1674 	else
1675 		return (NULL);
1676 }
1677 
1678 /*
1679  * Invoked by SIGALRM, sigalrm_handler() is, responsible for calling
1680  * send_scheduled_probe() to send next probe.
1681  */
1682 void
1683 sigalrm_handler(void)
1684 {
1685 	/*
1686 	 * Guard againist denial-of-service attacks. Make sure ping doesn't
1687 	 * send probes for every SIGALRM it receives. Evil hacker can generate
1688 	 * SIGALRMs as fast as it can, but ping will ignore those which are
1689 	 * received too soon (earlier than 0.5 sec) after it sent the last
1690 	 * probe.  We use gethrtime() instead of gettimeofday() because
1691 	 * the latter is not linear and is prone to resetting or drifting
1692 	 */
1693 	if ((gethrtime() - t_last_probe_sent) < 500000000) {
1694 		return;
1695 	}
1696 	send_scheduled_probe();
1697 	schedule_sigalrm();
1698 }
1699 
1700 /*
1701  * Schedule next SIGALRM.
1702  */
1703 void
1704 schedule_sigalrm(void)
1705 {
1706 	int waittime;
1707 
1708 	if (npackets == 0 ||
1709 	    current_targetaddr->num_sent < current_targetaddr->num_probes) {
1710 		(void) alarm(interval);
1711 	} else {
1712 		if (current_targetaddr->got_reply) {
1713 			waittime = 2 * tmax / MICROSEC;
1714 			if (waittime == 0)
1715 				waittime = 1;
1716 		} else {
1717 			waittime = MAX_WAIT;
1718 		}
1719 		(void) alarm(waittime);
1720 	}
1721 }
1722 
1723 /*
1724  * Called by sigalrm_handler(), check_reply() or check_reply6(),
1725  * send_scheduled_probe() looks at the current_targetaddr and determines what
1726  * should be sent next and calls pinger().
1727  */
1728 void
1729 send_scheduled_probe()
1730 {
1731 	static struct msghdr msg6;
1732 	static boolean_t first_probe = _B_TRUE;
1733 	char tmp_buf[INET6_ADDRSTRLEN];
1734 
1735 	/*
1736 	 * We are about to move to next targetaddr if it's either we sent
1737 	 * all the probes, or somebody set the probing_done flag to
1738 	 * _B_TRUE prompting us to move on.
1739 	 */
1740 	if (current_targetaddr->num_sent == current_targetaddr->num_probes ||
1741 	    current_targetaddr->probing_done) {
1742 		/*
1743 		 * is this a dead target?
1744 		 */
1745 		if (!stats && !current_targetaddr->got_reply) {
1746 			if (!probe_all) {
1747 				Printf("no answer from %s\n", targethost);
1748 			} else {
1749 				Printf("no answer from %s(%s)\n", targethost,
1750 				    inet_ntop(current_targetaddr->family,
1751 				    &current_targetaddr->dst_addr,
1752 				    tmp_buf, sizeof (tmp_buf)));
1753 			}
1754 		}
1755 		/*
1756 		 * Before we move onto next item, let's do some clean up.
1757 		 */
1758 		current_targetaddr->got_reply = _B_FALSE;
1759 		current_targetaddr->probing_done = _B_FALSE;
1760 		/*
1761 		 * If this is probe-all without stats mode, then we need to
1762 		 * preserve this count. This is needed when we try to map an
1763 		 * icmp_seq to IP address. Otherwise, clear it.
1764 		 */
1765 		if (stats || !probe_all)
1766 			current_targetaddr->num_sent = 0;
1767 		nreceived_last_target = 0;
1768 
1769 		current_targetaddr = current_targetaddr->next;
1770 
1771 		/*
1772 		 * Did we reach the end of road?
1773 		 */
1774 		if (current_targetaddr == NULL) {
1775 			(void) alarm(0);	/* cancel alarm */
1776 			if (stats)
1777 				finish();
1778 			if (is_alive)
1779 				exit(EXIT_SUCCESS);
1780 			else
1781 				exit(EXIT_FAILURE);
1782 		} else {
1783 			/*
1784 			 * We use starting_seq_num for authenticating replies.
1785 			 * Each time we move to a new targetaddr, which has
1786 			 * a different target IP address, we update this field.
1787 			 */
1788 			current_targetaddr->starting_seq_num = use_udp ?
1789 			    dest_port : (ntransmitted % (MAX_ICMP_SEQ + 1));
1790 		}
1791 	}
1792 
1793 	if (current_targetaddr->family == AF_INET6) {
1794 		if (send_reply) {
1795 			/* sending back to ourself */
1796 			to6.sin6_addr = current_targetaddr->src_addr.addr6;
1797 		} else {
1798 			to6.sin6_addr = current_targetaddr->dst_addr.addr6;
1799 		}
1800 		/*
1801 		 * Setting the ancillary data once is enough, if we are
1802 		 * not using source routing through target (-l/-S). In
1803 		 * case -l/-S used, the middle gateway will be the
1804 		 * IP address of the source, which can be different
1805 		 * for each target IP.
1806 		 */
1807 		if (first_probe ||
1808 		    (send_reply && current_targetaddr->num_sent == 0)) {
1809 			if (send_reply) {
1810 				/* target is the middle gateway now */
1811 				gw_IP_list6[num_gw].addr6 =
1812 				    current_targetaddr->dst_addr.addr6;
1813 			}
1814 			set_ancillary_data(&msg6, hoplimit, gw_IP_list6,
1815 			    eff_num_gw, if_index);
1816 			first_probe = _B_FALSE;
1817 		}
1818 		pinger(send_sock6, (struct sockaddr *)&to6, &msg6, AF_INET6);
1819 	} else {
1820 		to.sin_addr = current_targetaddr->dst_addr.addr;
1821 		/*
1822 		 * Set IPv4 options when sending the first probe to a target
1823 		 * IP address. Some options change when the target address
1824 		 * changes.
1825 		 */
1826 		if (current_targetaddr->num_sent == 0) {
1827 			if (eff_num_gw > 0) {
1828 				gw_IP_list[num_gw].addr =
1829 				    current_targetaddr->dst_addr.addr;
1830 				/*
1831 				 * If send_reply, the target becomes the
1832 				 * middle gateway, sender becomes the last
1833 				 * gateway.
1834 				 */
1835 				if (send_reply) {
1836 					gw_IP_list[eff_num_gw].addr =
1837 					    current_targetaddr->src_addr.addr;
1838 				}
1839 			}
1840 			/*
1841 			 * In IPv4, if source routing is used, the target
1842 			 * address shows up as the last gateway, hence +1.
1843 			 */
1844 			set_IPv4_options(send_sock, gw_IP_list,
1845 			    (eff_num_gw > 0) ? eff_num_gw + 1 : 0,
1846 			    &current_targetaddr->src_addr.addr, &to.sin_addr);
1847 		}
1848 		pinger(send_sock, (struct sockaddr *)&to, NULL, AF_INET);
1849 	}
1850 
1851 	current_targetaddr->num_sent++;
1852 }
1853 
1854 /*
1855  * recv_icmp_packet()'s job is to listen to icmp packets and filter out
1856  * those ping is interested in.
1857  */
1858 static void
1859 recv_icmp_packet(struct addrinfo *ai_dst, int recv_sock6, int recv_sock,
1860 ushort_t udp_src_port6, ushort_t udp_src_port)
1861 {
1862 	struct msghdr in_msg;
1863 	struct iovec iov;
1864 	struct sockaddr_in6 from6;
1865 	fd_set fds;
1866 	int result;
1867 	int cc;
1868 	boolean_t always_true = _B_TRUE; /* lint doesn't like while(_B_TRUE) */
1869 
1870 	while (always_true) {
1871 		(void) FD_ZERO(&fds);
1872 		if (recv_sock6 != -1)
1873 			FD_SET(recv_sock6, &fds);
1874 		if (recv_sock != -1)
1875 			FD_SET(recv_sock, &fds);
1876 
1877 		result = select(MAX(recv_sock6, recv_sock) + 1, &fds,
1878 		    (fd_set *)NULL, (fd_set *)NULL, (struct timeval *)NULL);
1879 		if (result == -1) {
1880 			if (errno == EINTR) {
1881 				continue;
1882 			} else {
1883 				Fprintf(stderr, "%s: select %s\n", progname,
1884 				    strerror(errno));
1885 				exit(EXIT_FAILURE);
1886 			}
1887 		} else if (result > 0) {
1888 			in_msg.msg_name = &from6;
1889 			in_msg.msg_namelen = sizeof (from6);
1890 			iov.iov_base = in_pkt;
1891 			iov.iov_len = sizeof (in_pkt);
1892 			in_msg.msg_iov = &iov;
1893 			in_msg.msg_iovlen = 1;
1894 			in_msg.msg_control = ancillary_data;
1895 			in_msg.msg_controllen = sizeof (ancillary_data);
1896 
1897 			/* Do we have an ICMP6 packet waiting? */
1898 			if ((recv_sock6 != -1) &&
1899 			    (FD_ISSET(recv_sock6, &fds))) {
1900 				cc = recvmsg(recv_sock6, &in_msg, 0);
1901 				if (cc < 0) {
1902 					if (errno != EINTR) {
1903 						Fprintf(stderr,
1904 						    "%s: recvmsg %s\n",
1905 						    progname, strerror(errno));
1906 					}
1907 					continue;
1908 				} else if (cc > 0) {
1909 					check_reply6(ai_dst, &in_msg, cc,
1910 					    udp_src_port6);
1911 				}
1912 			}
1913 			/* Do we have an ICMP packet waiting? */
1914 			if ((recv_sock != -1) && (FD_ISSET(recv_sock, &fds))) {
1915 				cc = recvmsg(recv_sock, &in_msg, 0);
1916 				if (cc < 0) {
1917 					if (errno != EINTR) {
1918 						Fprintf(stderr,
1919 						    "%s: recvmsg %s\n",
1920 						    progname, strerror(errno));
1921 					}
1922 					continue;
1923 				} if (cc > 0) {
1924 					check_reply(ai_dst, &in_msg, cc,
1925 					    udp_src_port);
1926 				}
1927 			}
1928 		}
1929 		/*
1930 		 * If we were probing last IP address of the target host and
1931 		 * received a reply for each probe sent to this address,
1932 		 * then we are done!
1933 		 */
1934 		if ((npackets > 0) && (current_targetaddr->next == NULL) &&
1935 		    (nreceived_last_target == npackets)) {
1936 			(void) alarm(0);	/* cancel alarm */
1937 			finish();
1938 		}
1939 	} /* infinite loop */
1940 }
1941 
1942 /*
1943  * Given a host (with possibly multiple IP addresses) and an IP address, this
1944  * function determines if this IP address is one of the host's addresses to
1945  * which we're sending probes. Used to determine if we are interested in a
1946  * packet.
1947  */
1948 boolean_t
1949 is_a_target(struct addrinfo *ai, union any_in_addr *addr)
1950 {
1951 	int num_addrs;
1952 	int i;
1953 	struct addrinfo *aip;
1954 
1955 	aip = ai;
1956 	if (probe_all)
1957 		num_addrs = num_v4 + num_v6;
1958 	else
1959 		num_addrs = 1;
1960 	for (i = 0; i < num_addrs && aip != NULL; i++) {
1961 		if (aip->ai_family == AF_INET6) {
1962 			/* LINTED E_BAD_PTR_CAST_ALIGN */
1963 			if (IN6_ARE_ADDR_EQUAL(&((struct sockaddr_in6 *)
1964 			    aip->ai_addr)->sin6_addr, &addr->addr6))
1965 				return (_B_TRUE);
1966 		} else {
1967 			/* LINTED E_BAD_PTR_CAST_ALIGN */
1968 			if (((struct sockaddr_in *)
1969 			    aip->ai_addr)->sin_addr.s_addr == addr->addr.s_addr)
1970 				return (_B_TRUE);
1971 		}
1972 	}
1973 
1974 	return (_B_FALSE);
1975 }
1976 
1977 /*
1978  * Compose and transmit an ICMP ECHO REQUEST packet.  The IP packet
1979  * will be added on by the kernel.  The ID field is our UNIX process ID,
1980  * and the sequence number is an ascending integer.  The first 8 bytes
1981  * of the data portion are used to hold a UNIX "timeval" struct in network
1982  * byte-order, to compute the round-trip time.
1983  */
1984 static void
1985 pinger(int send_sock, struct sockaddr *whereto, struct msghdr *msg6,
1986     int family)
1987 {
1988 	static uint64_t out_pkt_buf[(IP_MAXPACKET + 1) / 8];
1989 	uchar_t *out_pkt = (uchar_t *)&out_pkt_buf;
1990 	/* LINTED E_BAD_PTR_CAST_ALIGN */
1991 	struct icmp *icp = (struct icmp *)out_pkt;
1992 	/* LINTED E_BAD_PTR_CAST_ALIGN */
1993 	struct sockaddr_in6 *to6 = (struct sockaddr_in6 *)whereto;
1994 	/* LINTED E_BAD_PTR_CAST_ALIGN */
1995 	struct sockaddr_in *to = (struct sockaddr_in *)whereto;
1996 	struct timeval *tp;
1997 	struct timeval t_snd;
1998 	uchar_t *datap;
1999 	struct iovec iov;
2000 	int start = 0;
2001 	int cc;
2002 	int i;
2003 
2004 	/* using UDP? */
2005 	if (use_udp) {
2006 		cc = datalen;
2007 
2008 		/* LINTED E_BAD_PTR_CAST_ALIGN */
2009 		tp = (struct timeval *)out_pkt;
2010 		datap = &out_pkt[sizeof (struct timeval)];
2011 
2012 		/*
2013 		 * This sets the port whether we are handling a v4 or v6
2014 		 * sockaddr structure.
2015 		 */
2016 		to->sin_port = htons(dest_port);
2017 
2018 		dest_port = (dest_port + 1) % (MAX_PORT + 1);
2019 		ntransmitted++;
2020 	} else {	/* using ICMP */
2021 		cc = datalen + ICMP_MINLEN;
2022 
2023 		if (family == AF_INET6) {
2024 			icp->icmp_type = send_reply ?
2025 			    ICMP6_ECHO_REPLY : ICMP6_ECHO_REQUEST;
2026 		} else if (use_icmp_ts) {	/* family is AF_INET */
2027 			icp->icmp_type = send_reply ?
2028 			    ICMP_TSTAMPREPLY : ICMP_TSTAMP;
2029 		} else {
2030 			icp->icmp_type = send_reply ?
2031 			    ICMP_ECHOREPLY : ICMP_ECHO;
2032 		}
2033 
2034 		icp->icmp_code = 0;
2035 		icp->icmp_cksum = 0;
2036 		icp->icmp_seq = htons(ntransmitted++ % (MAX_ICMP_SEQ + 1));
2037 		if (icp->icmp_seq == 0)
2038 			num_wraps++;
2039 		icp->icmp_id = htons(ident);		/* ID */
2040 
2041 		/* LINTED E_BAD_PTR_CAST_ALIGN */
2042 		tp = (struct timeval *)&out_pkt[ICMP_MINLEN];
2043 		datap = &out_pkt[ICMP_MINLEN + sizeof (struct timeval)];
2044 	}
2045 
2046 	start = sizeof (struct timeval);	/* skip for time */
2047 
2048 	(void) gettimeofday(&t_snd, (struct timezone *)NULL);
2049 
2050 	/* if packet is big enough to store timeval OR ... */
2051 	if ((datalen >= sizeof (struct timeval)) ||
2052 	    (family == AF_INET && use_icmp_ts))
2053 		*tp = t_snd;
2054 
2055 	if (family == AF_INET && use_icmp_ts) {
2056 		start = sizeof (struct id_ts);	/* skip for ICMP timestamps */
2057 		/* Number of milliseconds since midnight */
2058 		icp->icmp_otime = htonl((tp->tv_sec % (24*60*60)) * 1000 +
2059 		    tp->tv_usec / 1000);
2060 	}
2061 
2062 	for (i = start; i < datalen; i++)
2063 		*datap++ = i;
2064 
2065 	if (family == AF_INET) {
2066 		if (!use_udp)
2067 			icp->icmp_cksum = in_cksum((ushort_t *)icp, cc);
2068 
2069 		i = sendto(send_sock, (char *)out_pkt, cc, 0, whereto,
2070 		    sizeof (struct sockaddr_in));
2071 	} else {
2072 		/*
2073 		 * Fill in the rest of the msghdr structure. msg_control is set
2074 		 * in set_ancillary_data().
2075 		 */
2076 		msg6->msg_name = to6;
2077 		msg6->msg_namelen = sizeof (struct sockaddr_in6);
2078 
2079 		iov.iov_base = out_pkt;
2080 		iov.iov_len = cc;
2081 
2082 		msg6->msg_iov = &iov;
2083 		msg6->msg_iovlen = 1;
2084 
2085 		i = sendmsg(send_sock, msg6, 0);
2086 	}
2087 
2088 	/* This is a more precise time (right after we send the packet) */
2089 	t_last_probe_sent = gethrtime();
2090 
2091 	if (i < 0 || i != cc)  {
2092 		if (i < 0) {
2093 			Fprintf(stderr, "%s: sendto %s\n", progname,
2094 			    strerror(errno));
2095 			if (!stats)
2096 				exit(EXIT_FAILURE);
2097 		}
2098 		Printf("ping: wrote %s %d chars, ret=%d\n",
2099 		    targethost, cc, i);
2100 		(void) fflush(stdout);
2101 	}
2102 }
2103 
2104 /*
2105  * Return a hostname for the given IP address.
2106  */
2107 char *
2108 pr_name(char *addr, int family)
2109 {
2110 	struct sockaddr_in sin;
2111 	struct sockaddr_in6 sin6;
2112 	struct sockaddr *sa;
2113 	static struct in6_addr prev_addr = IN6ADDR_ANY_INIT;
2114 	char *cp;
2115 	char abuf[INET6_ADDRSTRLEN];
2116 	static char buf[NI_MAXHOST + INET6_ADDRSTRLEN + 3];
2117 	uint_t slen, alen, hlen;
2118 
2119 	switch (family) {
2120 	case AF_INET:
2121 		(void) memset(&sin, 0, sizeof (sin));
2122 		slen = sizeof (struct sockaddr_in);
2123 		alen = sizeof (struct in_addr);
2124 		/* LINTED E_BAD_PTR_CAST_ALIGN */
2125 		sin.sin_addr = *(struct in_addr *)addr;
2126 		sin.sin_port = 0;
2127 		sa = (struct sockaddr *)&sin;
2128 		break;
2129 	case AF_INET6:
2130 		(void) memset(&sin6, 0, sizeof (sin6));
2131 		slen = sizeof (struct sockaddr_in6);
2132 		alen = sizeof (struct in6_addr);
2133 		/* LINTED E_BAD_PTR_CAST_ALIGN */
2134 		sin6.sin6_addr = *(struct in6_addr *)addr;
2135 		sin6.sin6_port = 0;
2136 		sa = (struct sockaddr *)&sin6;
2137 		break;
2138 	default:
2139 		(void) snprintf(buf, sizeof (buf), "<invalid address family>");
2140 		return (buf);
2141 	}
2142 	sa->sa_family = family;
2143 
2144 	/* compare with the buffered (previous) lookup */
2145 	if (memcmp(addr, &prev_addr, alen) != 0) {
2146 		int flags = (nflag) ? NI_NUMERICHOST : NI_NAMEREQD;
2147 		if (getnameinfo(sa, slen, buf, sizeof (buf),
2148 		    NULL, 0, flags) != 0) {
2149 			/* getnameinfo() failed; return just the address */
2150 			if (inet_ntop(family, (const void*)addr,
2151 			    buf, sizeof (buf)) == NULL)
2152 				buf[0] = 0;
2153 		} else if (!nflag) {
2154 			/* append numeric address to hostname string */
2155 			hlen = strlen(buf);
2156 			cp = (char *)(buf + hlen);
2157 			(void) snprintf(cp, sizeof (buf) - hlen, " (%s)",
2158 			    inet_ntop(family, (const void *)addr, abuf,
2159 			    sizeof (abuf)));
2160 		}
2161 
2162 		/* LINTED E_BAD_PTR_CAST_ALIGN */
2163 		prev_addr = *(struct in6_addr *)addr;
2164 	}
2165 	return (buf);
2166 }
2167 
2168 /*
2169  * Return the protocol string, given its protocol number.
2170  */
2171 char *
2172 pr_protocol(int prot)
2173 {
2174 	static char buf[20];
2175 
2176 	switch (prot) {
2177 	case IPPROTO_ICMPV6:
2178 		(void) strlcpy(buf, "icmp6", sizeof (buf));
2179 		break;
2180 
2181 	case IPPROTO_ICMP:
2182 		(void) strlcpy(buf, "icmp", sizeof (buf));
2183 		break;
2184 
2185 	case IPPROTO_TCP:
2186 		(void) strlcpy(buf, "tcp", sizeof (buf));
2187 		break;
2188 
2189 	case IPPROTO_UDP:
2190 		(void) strlcpy(buf, "udp", sizeof (buf));
2191 		break;
2192 
2193 	default:
2194 		(void) snprintf(buf, sizeof (buf), "prot %d", prot);
2195 		break;
2196 	}
2197 
2198 	return (buf);
2199 }
2200 
2201 /*
2202  * Checks if value is between seq_begin and seq_begin+seq_len. Note that
2203  * sequence numbers wrap around after MAX_ICMP_SEQ (== MAX_PORT).
2204  */
2205 boolean_t
2206 seq_match(ushort_t seq_begin, int seq_len, ushort_t value)
2207 {
2208 	/*
2209 	 * If seq_len is too big, like some value greater than MAX_ICMP_SEQ/2,
2210 	 * truncate it down to MAX_ICMP_SEQ/2. We are not going to accept any
2211 	 * reply which come 83hr later!
2212 	 */
2213 	if (seq_len > MAX_ICMP_SEQ / 2) {
2214 		seq_begin = (seq_begin + seq_len - MAX_ICMP_SEQ / 2) %
2215 		    (MAX_ICMP_SEQ + 1);
2216 		seq_len = MAX_ICMP_SEQ / 2;
2217 	}
2218 
2219 	if (PINGSEQ_LEQ(seq_begin, value) &&
2220 	    PINGSEQ_LEQ(value, (seq_begin + seq_len - 1) % (MAX_ICMP_SEQ + 1)))
2221 		return (_B_TRUE);
2222 	else
2223 		return (_B_FALSE);
2224 }
2225 
2226 /*
2227  * For a given icmp_seq, find which destination address we must have sent this
2228  * to.
2229  */
2230 void
2231 find_dstaddr(ushort_t icmpseq, union any_in_addr *ipaddr)
2232 {
2233 	struct targetaddr *target = targetaddr_list;
2234 	int real_seq;
2235 	int targetaddr_index;
2236 	int real_npackets;
2237 	int i;
2238 
2239 	ipaddr->addr6 = in6addr_any;
2240 
2241 	/*
2242 	 * If this is probe_all and not stats, then the number of probes sent to
2243 	 * each IP address may be different (remember, we stop sending to one IP
2244 	 * address as soon as it replies). They are stored in target->num_sent
2245 	 * field. Since we don't wrap around the list (!stats), they are also
2246 	 * preserved.
2247 	 */
2248 	if (probe_all && !stats) {
2249 		do {
2250 			if (seq_match(target->starting_seq_num,
2251 			    target->num_sent, icmpseq)) {
2252 				ipaddr->addr6 = target->dst_addr.addr6;
2253 				/*
2254 				 * We are not immediately return()ing here.
2255 				 * Because of wrapping, we might find another
2256 				 * match later, which is more likely to be the
2257 				 * real one.
2258 				 */
2259 			}
2260 			target = target->next;
2261 		} while (target != NULL);
2262 	} else {
2263 		/*
2264 		 * Find the absolute (non-wrapped) seq number within the last
2265 		 * 64K
2266 		 */
2267 		if (icmpseq < (ntransmitted % (MAX_ICMP_SEQ + 1))) {
2268 			real_seq = num_wraps * (MAX_ICMP_SEQ + 1) + icmpseq;
2269 		} else {
2270 			real_seq = (num_wraps - 1) * (MAX_ICMP_SEQ + 1) +
2271 			    icmpseq;
2272 		}
2273 
2274 		/* Make sure it's non-negative */
2275 		if (real_seq < 0)
2276 			return;
2277 		real_npackets = (npackets == 0) ? 1 : npackets;
2278 
2279 		/*
2280 		 * We sent npackets many packets to each of those
2281 		 * num_targetaddrs many IP addresses.
2282 		 */
2283 		targetaddr_index =
2284 		    (real_seq % (num_targetaddrs * real_npackets)) /
2285 		    real_npackets;
2286 		for (i = 0; i < targetaddr_index; i++)
2287 			target = target->next;
2288 		ipaddr->addr6 = target->dst_addr.addr6;
2289 	}
2290 }
2291 
2292 /*
2293  * Checksum routine for Internet Protocol family headers (C Version)
2294  */
2295 static ushort_t
2296 in_cksum(ushort_t *addr, int len)
2297 {
2298 	int nleft = len;
2299 	ushort_t *w = addr;
2300 	ushort_t answer;
2301 	ushort_t odd_byte = 0;
2302 	int sum = 0;
2303 
2304 	/*
2305 	 *  Our algorithm is simple, using a 32 bit accumulator (sum),
2306 	 *  we add sequential 16 bit words to it, and at the end, fold
2307 	 *  back all the carry bits from the top 16 bits into the lower
2308 	 *  16 bits.
2309 	 */
2310 	while (nleft > 1) {
2311 		sum += *w++;
2312 		nleft -= 2;
2313 	}
2314 
2315 	/* mop up an odd byte, if necessary */
2316 	if (nleft == 1) {
2317 		*(uchar_t *)(&odd_byte) = *(uchar_t *)w;
2318 		sum += odd_byte;
2319 	}
2320 
2321 	/*
2322 	 * add back carry outs from top 16 bits to low 16 bits
2323 	 */
2324 	sum = (sum >> 16) + (sum & 0xffff);	/* add hi 16 to low 16 */
2325 	sum += (sum >> 16);			/* add carry */
2326 	answer = ~sum;				/* truncate to 16 bits */
2327 	return (answer);
2328 }
2329 
2330 /*
2331  * Subtract 2 timeval structs:  out = out - in.
2332  * Out is assumed to be >= in.
2333  */
2334 void
2335 tvsub(struct timeval *out, struct timeval *in)
2336 {
2337 	if ((out->tv_usec -= in->tv_usec) < 0) {
2338 		out->tv_sec--;
2339 		out->tv_usec += 1000000;
2340 	}
2341 	out->tv_sec -= in->tv_sec;
2342 }
2343 
2344 /*
2345  * Print out statistics, and give up.
2346  * Heavily buffered STDIO is used here, so that all the statistics
2347  * will be written with 1 sys-write call.  This is nice when more
2348  * than one copy of the program is running on a terminal;  it prevents
2349  * the statistics output from becoming intermingled.
2350  */
2351 static void
2352 finish()
2353 {
2354 	Printf("\n----%s PING Statistics----\n", targethost);
2355 	Printf("%d packets transmitted, ", ntransmitted);
2356 	Printf("%d packets received, ", nreceived);
2357 	if (ntransmitted) {
2358 		if (nreceived <= ntransmitted) {
2359 			Printf("%d%% packet loss",
2360 			    (int)(((ntransmitted-nreceived)*100) /
2361 			    ntransmitted));
2362 		} else {
2363 			Printf("%.2f times amplification",
2364 			    (double)nreceived / (double)ntransmitted);
2365 		}
2366 	}
2367 	(void) putchar('\n');
2368 
2369 	/* if packet is big enough to store timeval AND ... */
2370 	if ((datalen >= sizeof (struct timeval)) && (nreceived > 0)) {
2371 		double mean = (double)tsum / nreceived;
2372 		double smean = (double)tsum2 / nreceived;
2373 		double sd =
2374 		    sqrt(((smean - mean*mean) * nreceived) / (nreceived-1));
2375 
2376 		Printf("round-trip (ms)  min/avg/max/stddev = "
2377 		    TIMEFORMAT "/" TIMEFORMAT "/"
2378 		    TIMEFORMAT "/" TIMEFORMAT "\n",
2379 		    (double)tmin / 1000, mean / 1000,
2380 		    (double)tmax / 1000, sd / 1000);
2381 	}
2382 	(void) fflush(stdout);
2383 
2384 	exit(is_alive ? EXIT_SUCCESS : EXIT_FAILURE);
2385 }
2386 
2387 /*
2388  * print the usage line
2389  */
2390 static void
2391 usage(char *cmdname)
2392 {
2393 	Fprintf(stderr, "usage: %s host [timeout]\n", cmdname);
2394 	Fprintf(stderr,
2395 /* CSTYLED */
2396 "usage: %s -s [-l | U] [abdDLnRrv] [-A addr_family] [-c traffic_class]\n\t"
2397 "[-g gateway [-g gateway ...]] [-N nexthop] [-F flow_label] [-I interval]\n\t"
2398 "[-i interface] [-P tos] [-p port] [-t ttl] host [data_size] [npackets]\n",
2399 	    cmdname);
2400 }
2401 
2402 /*
2403  * Parse integer argument; exit with an error if it's not a number.
2404  * Now it also accepts hex. values.
2405  */
2406 static int
2407 int_arg(char *s, char *what)
2408 {
2409 	char *cp;
2410 	char *ep;
2411 	int num;
2412 
2413 	errno = 0;
2414 	if (s[0] == '0' && (s[1] == 'x' || s[1] == 'X')) {
2415 		cp = s + 2;
2416 		num = (int)strtol(cp, &ep, 16);
2417 	} else {
2418 		num = (int)strtol(s, &ep, 10);
2419 	}
2420 
2421 	if (errno || *ep != '\0' || num < 0) {
2422 		(void) Fprintf(stderr, "%s: bad %s: %s\n",
2423 		    progname, what, s);
2424 		exit(EXIT_FAILURE);
2425 	}
2426 
2427 	return (num);
2428 }
2429