xref: /freebsd/usr.bin/netstat/main.c (revision 3416500aef140042c64bc149cb1ec6620483bc44)
1 /*-
2  * Copyright (c) 1983, 1988, 1993
3  *	Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #ifndef lint
31 static char const copyright[] =
32 "@(#) Copyright (c) 1983, 1988, 1993\n\
33 	Regents of the University of California.  All rights reserved.\n";
34 #endif /* not lint */
35 
36 #if 0
37 #ifndef lint
38 static char sccsid[] = "@(#)main.c	8.4 (Berkeley) 3/1/94";
39 #endif /* not lint */
40 #endif
41 
42 #include <sys/cdefs.h>
43 __FBSDID("$FreeBSD$");
44 
45 #include <sys/param.h>
46 #include <sys/file.h>
47 #include <sys/protosw.h>
48 #include <sys/socket.h>
49 #include <sys/socketvar.h>
50 #include <sys/sysctl.h>
51 
52 #include <netinet/in.h>
53 
54 #ifdef NETGRAPH
55 #include <netgraph/ng_socket.h>
56 #endif
57 
58 #include <ctype.h>
59 #include <err.h>
60 #include <errno.h>
61 #include <kvm.h>
62 #include <limits.h>
63 #include <netdb.h>
64 #include <nlist.h>
65 #include <paths.h>
66 #include <stdint.h>
67 #include <stdio.h>
68 #include <stdlib.h>
69 #include <stdbool.h>
70 #include <string.h>
71 #include <unistd.h>
72 #include "netstat.h"
73 #include "nl_defs.h"
74 #include <libxo/xo.h>
75 
76 static struct protox {
77 	int	pr_index;		/* index into nlist of cb head */
78 	int	pr_sindex;		/* index into nlist of stat block */
79 	u_char	pr_wanted;		/* 1 if wanted, 0 otherwise */
80 	void	(*pr_cblocks)(u_long, const char *, int, int);
81 					/* control blocks printing routine */
82 	void	(*pr_stats)(u_long, const char *, int, int);
83 					/* statistics printing routine */
84 	void	(*pr_istats)(char *);	/* per/if statistics printing routine */
85 	const char	*pr_name;		/* well-known name */
86 	int	pr_usesysctl;		/* non-zero if we use sysctl, not kvm */
87 	int	pr_protocol;
88 } protox[] = {
89 	{ N_TCBINFO,	N_TCPSTAT,	1,	protopr,
90 	  tcp_stats,	NULL,		"tcp",	1,	IPPROTO_TCP },
91 	{ N_UDBINFO,	N_UDPSTAT,	1,	protopr,
92 	  udp_stats,	NULL,		"udp",	1,	IPPROTO_UDP },
93 #ifdef SCTP
94 	{ -1,		N_SCTPSTAT,	1,	sctp_protopr,
95 	  sctp_stats,	NULL,		"sctp",	1,	IPPROTO_SCTP },
96 #endif
97 #ifdef SDP
98 	{ -1,		-1,		1,	protopr,
99 	 NULL,		NULL,		"sdp",	1,	IPPROTO_TCP },
100 #endif
101 	{ N_DIVCBINFO,	-1,		1,	protopr,
102 	  NULL,		NULL,		"divert", 1,	IPPROTO_DIVERT },
103 	{ N_RIPCBINFO,	N_IPSTAT,	1,	protopr,
104 	  ip_stats,	NULL,		"ip",	1,	IPPROTO_RAW },
105 	{ N_RIPCBINFO,	N_ICMPSTAT,	1,	protopr,
106 	  icmp_stats,	NULL,		"icmp",	1,	IPPROTO_ICMP },
107 	{ N_RIPCBINFO,	N_IGMPSTAT,	1,	protopr,
108 	  igmp_stats,	NULL,		"igmp",	1,	IPPROTO_IGMP },
109 #ifdef IPSEC
110 	{ -1,		N_IPSEC4STAT,	1,	NULL,	/* keep as compat */
111 	  ipsec_stats,	NULL,		"ipsec", 1,	0},
112 	{ -1,		N_AHSTAT,	1,	NULL,
113 	  ah_stats,	NULL,		"ah",	1,	0},
114 	{ -1,		N_ESPSTAT,	1,	NULL,
115 	  esp_stats,	NULL,		"esp",	1,	0},
116 	{ -1,		N_IPCOMPSTAT,	1,	NULL,
117 	  ipcomp_stats,	NULL,		"ipcomp", 1,	0},
118 #endif
119 	{ N_RIPCBINFO,	N_PIMSTAT,	1,	protopr,
120 	  pim_stats,	NULL,		"pim",	1,	IPPROTO_PIM },
121 	{ -1,		N_CARPSTATS,	1,	NULL,
122 	  carp_stats,	NULL,		"carp",	1,	0 },
123 #ifdef PF
124 	{ -1,		N_PFSYNCSTATS,	1,	NULL,
125 	  pfsync_stats,	NULL,		"pfsync", 1,	0 },
126 #endif
127 	{ -1,		N_ARPSTAT,	1,	NULL,
128 	  arp_stats,	NULL,		"arp", 1,	0 },
129 	{ -1,		-1,		0,	NULL,
130 	  NULL,		NULL,		NULL,	0,	0 }
131 };
132 
133 #ifdef INET6
134 static struct protox ip6protox[] = {
135 	{ N_TCBINFO,	N_TCPSTAT,	1,	protopr,
136 	  tcp_stats,	NULL,		"tcp",	1,	IPPROTO_TCP },
137 	{ N_UDBINFO,	N_UDPSTAT,	1,	protopr,
138 	  udp_stats,	NULL,		"udp",	1,	IPPROTO_UDP },
139 	{ N_RIPCBINFO,	N_IP6STAT,	1,	protopr,
140 	  ip6_stats,	ip6_ifstats,	"ip6",	1,	IPPROTO_RAW },
141 	{ N_RIPCBINFO,	N_ICMP6STAT,	1,	protopr,
142 	  icmp6_stats,	icmp6_ifstats,	"icmp6", 1,	IPPROTO_ICMPV6 },
143 #ifdef SDP
144 	{ -1,		-1,		1,	protopr,
145 	 NULL,		NULL,		"sdp",	1,	IPPROTO_TCP },
146 #endif
147 #ifdef IPSEC
148 	{ -1,		N_IPSEC6STAT,	1,	NULL,
149 	  ipsec_stats,	NULL,		"ipsec6", 1,	0 },
150 #endif
151 #ifdef notyet
152 	{ -1,		N_PIM6STAT,	1,	NULL,
153 	  pim6_stats,	NULL,		"pim6",	1,	0 },
154 #endif
155 	{ -1,		N_RIP6STAT,	1,	NULL,
156 	  rip6_stats,	NULL,		"rip6",	1,	0 },
157 	{ -1,		-1,		0,	NULL,
158 	  NULL,		NULL,		NULL,	0,	0 }
159 };
160 #endif /*INET6*/
161 
162 #ifdef IPSEC
163 static struct protox pfkeyprotox[] = {
164 	{ -1,		N_PFKEYSTAT,	1,	NULL,
165 	  pfkey_stats,	NULL,		"pfkey", 0,	0 },
166 	{ -1,		-1,		0,	NULL,
167 	  NULL,		NULL,		NULL,	0,	0 }
168 };
169 #endif
170 
171 #ifdef NETGRAPH
172 static struct protox netgraphprotox[] = {
173 	{ N_NGSOCKLIST,	-1,		1,	netgraphprotopr,
174 	  NULL,		NULL,		"ctrl",	0,	0 },
175 	{ N_NGSOCKLIST,	-1,		1,	netgraphprotopr,
176 	  NULL,		NULL,		"data",	0,	0 },
177 	{ -1,		-1,		0,	NULL,
178 	  NULL,		NULL,		NULL,	0,	0 }
179 };
180 #endif
181 
182 static struct protox *protoprotox[] = {
183 					 protox,
184 #ifdef INET6
185 					 ip6protox,
186 #endif
187 #ifdef IPSEC
188 					 pfkeyprotox,
189 #endif
190 					 NULL };
191 
192 static void printproto(struct protox *, const char *, bool *);
193 static void usage(void);
194 static struct protox *name2protox(const char *);
195 static struct protox *knownname(const char *);
196 
197 static int kresolve_list(struct nlist *_nl);
198 
199 static kvm_t *kvmd;
200 static char *nlistf = NULL, *memf = NULL;
201 
202 int	Aflag;		/* show addresses of protocol control block */
203 int	aflag;		/* show all sockets (including servers) */
204 static int	Bflag;		/* show information about bpf consumers */
205 int	bflag;		/* show i/f total bytes in/out */
206 int	dflag;		/* show i/f dropped packets */
207 int	gflag;		/* show group (multicast) routing or stats */
208 int	hflag;		/* show counters in human readable format */
209 int	iflag;		/* show interfaces */
210 int	Lflag;		/* show size of listen queues */
211 int	mflag;		/* show memory stats */
212 int	noutputs = 0;	/* how much outputs before we exit */
213 int	numeric_addr;	/* show addresses numerically */
214 int	numeric_port;	/* show ports numerically */
215 static int pflag;	/* show given protocol */
216 static int	Qflag;		/* show netisr information */
217 int	rflag;		/* show routing tables (or routing stats) */
218 int	Rflag;		/* show flow / RSS statistics */
219 int	sflag;		/* show protocol statistics */
220 int	Wflag;		/* wide display */
221 int	Tflag;		/* TCP Information */
222 int	xflag;		/* extra information, includes all socket buffer info */
223 int	zflag;		/* zero stats */
224 
225 int	interval;	/* repeat interval for i/f stats */
226 
227 char	*interface;	/* desired i/f for stats, or NULL for all i/fs */
228 int	unit;		/* unit number for above */
229 
230 static int	af;		/* address family */
231 int	live;		/* true if we are examining a live system */
232 
233 int
234 main(int argc, char *argv[])
235 {
236 	struct protox *tp = NULL;  /* for printing cblocks & stats */
237 	int ch;
238 	int fib = -1;
239 	char *endptr;
240 	bool first = true;
241 
242 	af = AF_UNSPEC;
243 
244 	argc = xo_parse_args(argc, argv);
245 	if (argc < 0)
246 		exit(EXIT_FAILURE);
247 
248 	while ((ch = getopt(argc, argv, "46AaBbdF:f:ghI:iLlM:mN:np:Qq:RrSTsuWw:xz"))
249 	    != -1)
250 		switch(ch) {
251 		case '4':
252 #ifdef INET
253 			af = AF_INET;
254 #else
255 			errx(1, "IPv4 support is not compiled in");
256 #endif
257 			break;
258 		case '6':
259 #ifdef INET6
260 			af = AF_INET6;
261 #else
262 			errx(1, "IPv6 support is not compiled in");
263 #endif
264 			break;
265 		case 'A':
266 			Aflag = 1;
267 			break;
268 		case 'a':
269 			aflag = 1;
270 			break;
271 		case 'B':
272 			Bflag = 1;
273 			break;
274 		case 'b':
275 			bflag = 1;
276 			break;
277 		case 'd':
278 			dflag = 1;
279 			break;
280 		case 'F':
281 			fib = strtol(optarg, &endptr, 0);
282 			if (*endptr != '\0' ||
283 			    (fib == 0 && (errno == EINVAL || errno == ERANGE)))
284 				xo_errx(1, "%s: invalid fib", optarg);
285 			break;
286 		case 'f':
287 			if (strcmp(optarg, "inet") == 0)
288 				af = AF_INET;
289 #ifdef INET6
290 			else if (strcmp(optarg, "inet6") == 0)
291 				af = AF_INET6;
292 #endif
293 #ifdef IPSEC
294 			else if (strcmp(optarg, "pfkey") == 0)
295 				af = PF_KEY;
296 #endif
297 			else if (strcmp(optarg, "unix") == 0 ||
298 				 strcmp(optarg, "local") == 0)
299 				af = AF_UNIX;
300 #ifdef NETGRAPH
301 			else if (strcmp(optarg, "ng") == 0
302 			    || strcmp(optarg, "netgraph") == 0)
303 				af = AF_NETGRAPH;
304 #endif
305 			else if (strcmp(optarg, "link") == 0)
306 				af = AF_LINK;
307 			else {
308 				xo_errx(1, "%s: unknown address family",
309 				    optarg);
310 			}
311 			break;
312 		case 'g':
313 			gflag = 1;
314 			break;
315 		case 'h':
316 			hflag = 1;
317 			break;
318 		case 'I': {
319 			char *cp;
320 
321 			iflag = 1;
322 			for (cp = interface = optarg; isalpha(*cp); cp++)
323 				continue;
324 			unit = atoi(cp);
325 			break;
326 		}
327 		case 'i':
328 			iflag = 1;
329 			break;
330 		case 'L':
331 			Lflag = 1;
332 			break;
333 		case 'M':
334 			memf = optarg;
335 			break;
336 		case 'm':
337 			mflag = 1;
338 			break;
339 		case 'N':
340 			nlistf = optarg;
341 			break;
342 		case 'n':
343 			numeric_addr = numeric_port = 1;
344 			break;
345 		case 'p':
346 			if ((tp = name2protox(optarg)) == NULL) {
347 				xo_errx(1, "%s: unknown or uninstrumented "
348 				    "protocol", optarg);
349 			}
350 			pflag = 1;
351 			break;
352 		case 'Q':
353 			Qflag = 1;
354 			break;
355 		case 'q':
356 			noutputs = atoi(optarg);
357 			if (noutputs != 0)
358 				noutputs++;
359 			break;
360 		case 'r':
361 			rflag = 1;
362 			break;
363 		case 'R':
364 			Rflag = 1;
365 			break;
366 		case 's':
367 			++sflag;
368 			break;
369 		case 'S':
370 			numeric_addr = 1;
371 			break;
372 		case 'u':
373 			af = AF_UNIX;
374 			break;
375 		case 'W':
376 		case 'l':
377 			Wflag = 1;
378 			break;
379 		case 'w':
380 			interval = atoi(optarg);
381 			iflag = 1;
382 			break;
383 		case 'T':
384 			Tflag = 1;
385 			break;
386 		case 'x':
387 			xflag = 1;
388 			break;
389 		case 'z':
390 			zflag = 1;
391 			break;
392 		case '?':
393 		default:
394 			usage();
395 		}
396 	argv += optind;
397 	argc -= optind;
398 
399 #define	BACKWARD_COMPATIBILITY
400 #ifdef	BACKWARD_COMPATIBILITY
401 	if (*argv) {
402 		if (isdigit(**argv)) {
403 			interval = atoi(*argv);
404 			if (interval <= 0)
405 				usage();
406 			++argv;
407 			iflag = 1;
408 		}
409 		if (*argv) {
410 			nlistf = *argv;
411 			if (*++argv)
412 				memf = *argv;
413 		}
414 	}
415 #endif
416 
417 	/*
418 	 * Discard setgid privileges if not the running kernel so that bad
419 	 * guys can't print interesting stuff from kernel memory.
420 	 */
421 	live = (nlistf == NULL && memf == NULL);
422 	if (!live) {
423 		if (setgid(getgid()) != 0)
424 			xo_err(-1, "setgid");
425 	}
426 
427 	if (xflag && Tflag)
428 		xo_errx(1, "-x and -T are incompatible, pick one.");
429 
430 	/* Load all necessary kvm symbols */
431 	kresolve_list(nl);
432 
433 	if (Bflag) {
434 		if (!live)
435 			usage();
436 		bpf_stats(interface);
437 		xo_finish();
438 		exit(0);
439 	}
440 	if (mflag) {
441 		if (!live) {
442 			if (kread(0, NULL, 0) == 0)
443 				mbpr(kvmd, nl[N_SFSTAT].n_value);
444 		} else
445 			mbpr(NULL, 0);
446 		xo_finish();
447 		exit(0);
448 	}
449 	if (Qflag) {
450 		if (!live) {
451 			if (kread(0, NULL, 0) == 0)
452 				netisr_stats();
453 		} else
454 			netisr_stats();
455 		xo_finish();
456 		exit(0);
457 	}
458 #if 0
459 	/*
460 	 * Keep file descriptors open to avoid overhead
461 	 * of open/close on each call to get* routines.
462 	 */
463 	sethostent(1);
464 	setnetent(1);
465 #else
466 	/*
467 	 * This does not make sense any more with DNS being default over
468 	 * the files.  Doing a setXXXXent(1) causes a tcp connection to be
469 	 * used for the queries, which is slower.
470 	 */
471 #endif
472 	if (iflag && !sflag) {
473 		xo_open_container("statistics");
474 		intpr(NULL, af);
475 		xo_close_container("statistics");
476 		xo_finish();
477 		exit(0);
478 	}
479 	if (rflag) {
480 		xo_open_container("statistics");
481 		if (sflag) {
482 			rt_stats();
483 			flowtable_stats();
484 		} else
485 			routepr(fib, af);
486 		xo_close_container("statistics");
487 		xo_finish();
488 		exit(0);
489 	}
490 
491 	if (gflag) {
492 		xo_open_container("statistics");
493 		if (sflag) {
494 			if (af == AF_INET || af == AF_UNSPEC)
495 				mrt_stats();
496 #ifdef INET6
497 			if (af == AF_INET6 || af == AF_UNSPEC)
498 				mrt6_stats();
499 #endif
500 		} else {
501 			if (af == AF_INET || af == AF_UNSPEC)
502 				mroutepr();
503 #ifdef INET6
504 			if (af == AF_INET6 || af == AF_UNSPEC)
505 				mroute6pr();
506 #endif
507 		}
508 		xo_close_container("statistics");
509 		xo_finish();
510 		exit(0);
511 	}
512 
513 	if (tp) {
514 		xo_open_container("statistics");
515 		printproto(tp, tp->pr_name, &first);
516 		if (!first)
517 			xo_close_list("socket");
518 		xo_close_container("statistics");
519 		xo_finish();
520 		exit(0);
521 	}
522 
523 	xo_open_container("statistics");
524 	if (af == AF_INET || af == AF_UNSPEC)
525 		for (tp = protox; tp->pr_name; tp++)
526 			printproto(tp, tp->pr_name, &first);
527 #ifdef INET6
528 	if (af == AF_INET6 || af == AF_UNSPEC)
529 		for (tp = ip6protox; tp->pr_name; tp++)
530 			printproto(tp, tp->pr_name, &first);
531 #endif /*INET6*/
532 #ifdef IPSEC
533 	if (af == PF_KEY || af == AF_UNSPEC)
534 		for (tp = pfkeyprotox; tp->pr_name; tp++)
535 			printproto(tp, tp->pr_name, &first);
536 #endif /*IPSEC*/
537 #ifdef NETGRAPH
538 	if (af == AF_NETGRAPH || af == AF_UNSPEC)
539 		for (tp = netgraphprotox; tp->pr_name; tp++)
540 			printproto(tp, tp->pr_name, &first);
541 #endif /* NETGRAPH */
542 	if ((af == AF_UNIX || af == AF_UNSPEC) && !sflag)
543 		unixpr(nl[N_UNP_COUNT].n_value, nl[N_UNP_GENCNT].n_value,
544 		    nl[N_UNP_DHEAD].n_value, nl[N_UNP_SHEAD].n_value,
545 		    nl[N_UNP_SPHEAD].n_value, &first);
546 
547 	if (!first)
548 		xo_close_list("socket");
549 	xo_close_container("statistics");
550 	xo_finish();
551 	exit(0);
552 }
553 
554 static int
555 fetch_stats_internal(const char *sysctlname, u_long off, void *stats,
556     size_t len, kreadfn_t kreadfn, int zero)
557 {
558 	int error;
559 
560 	if (live) {
561 		memset(stats, 0, len);
562 		if (zero)
563 			error = sysctlbyname(sysctlname, NULL, NULL, stats,
564 			    len);
565 		else
566 			error = sysctlbyname(sysctlname, stats, &len, NULL, 0);
567 		if (error == -1 && errno != ENOENT)
568 			xo_warn("sysctl %s", sysctlname);
569 	} else {
570 		if (off == 0)
571 			return (1);
572 		error = kreadfn(off, stats, len);
573 	}
574 	return (error);
575 }
576 
577 int
578 fetch_stats(const char *sysctlname, u_long off, void *stats,
579     size_t len, kreadfn_t kreadfn)
580 {
581 
582 	return (fetch_stats_internal(sysctlname, off, stats, len, kreadfn,
583     zflag));
584 }
585 
586 int
587 fetch_stats_ro(const char *sysctlname, u_long off, void *stats,
588     size_t len, kreadfn_t kreadfn)
589 {
590 
591 	return (fetch_stats_internal(sysctlname, off, stats, len, kreadfn, 0));
592 }
593 
594 /*
595  * Print out protocol statistics or control blocks (per sflag).
596  * If the interface was not specifically requested, and the symbol
597  * is not in the namelist, ignore this one.
598  */
599 static void
600 printproto(struct protox *tp, const char *name, bool *first)
601 {
602 	void (*pr)(u_long, const char *, int, int);
603 	u_long off;
604 	bool doingdblocks = false;
605 
606 	if (sflag) {
607 		if (iflag) {
608 			if (tp->pr_istats)
609 				intpr(tp->pr_istats, af);
610 			else if (pflag)
611 				xo_message("%s: no per-interface stats routine",
612 				    tp->pr_name);
613 			return;
614 		} else {
615 			pr = tp->pr_stats;
616 			if (!pr) {
617 				if (pflag)
618 					xo_message("%s: no stats routine",
619 					    tp->pr_name);
620 				return;
621 			}
622 			if (tp->pr_usesysctl && live)
623 				off = 0;
624 			else if (tp->pr_sindex < 0) {
625 				if (pflag)
626 					xo_message("%s: stats routine doesn't "
627 					    "work on cores", tp->pr_name);
628 				return;
629 			} else
630 				off = nl[tp->pr_sindex].n_value;
631 		}
632 	} else {
633 		doingdblocks = true;
634 		pr = tp->pr_cblocks;
635 		if (!pr) {
636 			if (pflag)
637 				xo_message("%s: no PCB routine", tp->pr_name);
638 			return;
639 		}
640 		if (tp->pr_usesysctl && live)
641 			off = 0;
642 		else if (tp->pr_index < 0) {
643 			if (pflag)
644 				xo_message("%s: PCB routine doesn't work on "
645 				    "cores", tp->pr_name);
646 			return;
647 		} else
648 			off = nl[tp->pr_index].n_value;
649 	}
650 	if (pr != NULL && (off || (live && tp->pr_usesysctl) ||
651 	    af != AF_UNSPEC)) {
652 		if (doingdblocks && *first) {
653 			xo_open_list("socket");
654 			*first = false;
655 		}
656 
657 		(*pr)(off, name, af, tp->pr_protocol);
658 	}
659 }
660 
661 static int
662 kvmd_init(void)
663 {
664 	char errbuf[_POSIX2_LINE_MAX];
665 
666 	if (kvmd != NULL)
667 		return (0);
668 
669 	kvmd = kvm_openfiles(nlistf, memf, NULL, O_RDONLY, errbuf);
670 	if (setgid(getgid()) != 0)
671 		xo_err(-1, "setgid");
672 
673 	if (kvmd == NULL) {
674 		xo_warnx("kvm not available: %s", errbuf);
675 		return (-1);
676 	}
677 
678 	return (0);
679 }
680 
681 /*
682  * Resolve symbol list, return 0 on success.
683  */
684 static int
685 kresolve_list(struct nlist *_nl)
686 {
687 
688 	if ((kvmd == NULL) && (kvmd_init() != 0))
689 		return (-1);
690 
691 	if (_nl[0].n_type != 0)
692 		return (0);
693 
694 	if (kvm_nlist(kvmd, _nl) < 0) {
695 		if (nlistf)
696 			xo_errx(1, "%s: kvm_nlist: %s", nlistf,
697 			    kvm_geterr(kvmd));
698 		else
699 			xo_errx(1, "kvm_nlist: %s", kvm_geterr(kvmd));
700 	}
701 
702 	return (0);
703 }
704 
705 /*
706  * Wrapper of kvm_dpcpu_setcpu().
707  */
708 void
709 kset_dpcpu(u_int cpuid)
710 {
711 
712 	if ((kvmd == NULL) && (kvmd_init() != 0))
713 		xo_errx(-1, "%s: kvm is not available", __func__);
714 
715 	if (kvm_dpcpu_setcpu(kvmd, cpuid) < 0)
716 		xo_errx(-1, "%s: kvm_dpcpu_setcpu(%u): %s", __func__,
717 		    cpuid, kvm_geterr(kvmd));
718 	return;
719 }
720 
721 /*
722  * Read kernel memory, return 0 on success.
723  */
724 int
725 kread(u_long addr, void *buf, size_t size)
726 {
727 
728 	if (kvmd_init() < 0)
729 		return (-1);
730 
731 	if (!buf)
732 		return (0);
733 	if (kvm_read(kvmd, addr, buf, size) != (ssize_t)size) {
734 		xo_warnx("%s", kvm_geterr(kvmd));
735 		return (-1);
736 	}
737 	return (0);
738 }
739 
740 /*
741  * Read single counter(9).
742  */
743 uint64_t
744 kread_counter(u_long addr)
745 {
746 
747 	if (kvmd_init() < 0)
748 		return (-1);
749 
750 	return (kvm_counter_u64_fetch(kvmd, addr));
751 }
752 
753 /*
754  * Read an array of N counters in kernel memory into array of N uint64_t's.
755  */
756 int
757 kread_counters(u_long addr, void *buf, size_t size)
758 {
759 	uint64_t *c;
760 	u_long *counters;
761 	size_t i, n;
762 
763 	if (kvmd_init() < 0)
764 		return (-1);
765 
766 	if (size % sizeof(uint64_t) != 0) {
767 		xo_warnx("kread_counters: invalid counter set size");
768 		return (-1);
769 	}
770 
771 	n = size / sizeof(uint64_t);
772 	if ((counters = malloc(n * sizeof(u_long))) == NULL)
773 		xo_err(-1, "malloc");
774 	if (kread(addr, counters, n * sizeof(u_long)) < 0) {
775 		free(counters);
776 		return (-1);
777 	}
778 
779 	c = buf;
780 	for (i = 0; i < n; i++)
781 		c[i] = kvm_counter_u64_fetch(kvmd, counters[i]);
782 
783 	free(counters);
784 	return (0);
785 }
786 
787 const char *
788 plural(uintmax_t n)
789 {
790 	return (n != 1 ? "s" : "");
791 }
792 
793 const char *
794 plurales(uintmax_t n)
795 {
796 	return (n != 1 ? "es" : "");
797 }
798 
799 const char *
800 pluralies(uintmax_t n)
801 {
802 	return (n != 1 ? "ies" : "y");
803 }
804 
805 /*
806  * Find the protox for the given "well-known" name.
807  */
808 static struct protox *
809 knownname(const char *name)
810 {
811 	struct protox **tpp, *tp;
812 
813 	for (tpp = protoprotox; *tpp; tpp++)
814 		for (tp = *tpp; tp->pr_name; tp++)
815 			if (strcmp(tp->pr_name, name) == 0)
816 				return (tp);
817 	return (NULL);
818 }
819 
820 /*
821  * Find the protox corresponding to name.
822  */
823 static struct protox *
824 name2protox(const char *name)
825 {
826 	struct protox *tp;
827 	char **alias;			/* alias from p->aliases */
828 	struct protoent *p;
829 
830 	/*
831 	 * Try to find the name in the list of "well-known" names. If that
832 	 * fails, check if name is an alias for an Internet protocol.
833 	 */
834 	if ((tp = knownname(name)) != NULL)
835 		return (tp);
836 
837 	setprotoent(1);			/* make protocol lookup cheaper */
838 	while ((p = getprotoent()) != NULL) {
839 		/* assert: name not same as p->name */
840 		for (alias = p->p_aliases; *alias; alias++)
841 			if (strcmp(name, *alias) == 0) {
842 				endprotoent();
843 				return (knownname(p->p_name));
844 			}
845 	}
846 	endprotoent();
847 	return (NULL);
848 }
849 
850 static void
851 usage(void)
852 {
853 	(void)xo_error("%s\n%s\n%s\n%s\n%s\n%s\n%s\n%s\n%s\n%s\n%s\n%s\n",
854 "usage: netstat [-46AaLnRSTWx] [-f protocol_family | -p protocol]\n"
855 "               [-M core] [-N system]",
856 "       netstat -i | -I interface [-46abdhnW] [-f address_family]\n"
857 "               [-M core] [-N system]",
858 "       netstat -w wait [-I interface] [-46d] [-M core] [-N system]\n"
859 "               [-q howmany]",
860 "       netstat -s [-46sz] [-f protocol_family | -p protocol]\n"
861 "               [-M core] [-N system]",
862 "       netstat -i | -I interface -s [-46s]\n"
863 "               [-f protocol_family | -p protocol] [-M core] [-N system]",
864 "       netstat -m [-M core] [-N system]",
865 "       netstat -B [-z] [-I interface]",
866 "       netstat -r [-46AnW] [-F fibnum] [-f address_family]\n"
867 "               [-M core] [-N system]",
868 "       netstat -rs [-s] [-M core] [-N system]",
869 "       netstat -g [-46W] [-f address_family] [-M core] [-N system]",
870 "       netstat -gs [-46s] [-f address_family] [-M core] [-N system]",
871 "       netstat -Q");
872 	xo_finish();
873 	exit(1);
874 }
875