xref: /freebsd/usr.bin/netstat/main.c (revision 2529f56e)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1983, 1988, 1993
5  *	Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #ifndef lint
33 static char const copyright[] =
34 "@(#) Copyright (c) 1983, 1988, 1993\n\
35 	Regents of the University of California.  All rights reserved.\n";
36 #endif /* not lint */
37 
38 #if 0
39 #ifndef lint
40 static char sccsid[] = "@(#)main.c	8.4 (Berkeley) 3/1/94";
41 #endif /* not lint */
42 #endif
43 
44 #include <sys/cdefs.h>
45 __FBSDID("$FreeBSD$");
46 
47 #include <sys/param.h>
48 #include <sys/file.h>
49 #include <sys/protosw.h>
50 #include <sys/socket.h>
51 #include <sys/socketvar.h>
52 #include <sys/sysctl.h>
53 
54 #include <netinet/in.h>
55 
56 #ifdef NETGRAPH
57 #include <netgraph/ng_socket.h>
58 #endif
59 
60 #include <ctype.h>
61 #include <err.h>
62 #include <errno.h>
63 #include <kvm.h>
64 #include <limits.h>
65 #include <netdb.h>
66 #include <nlist.h>
67 #include <paths.h>
68 #include <stdint.h>
69 #include <stdio.h>
70 #include <stdlib.h>
71 #include <stdbool.h>
72 #include <string.h>
73 #include <unistd.h>
74 #include "netstat.h"
75 #include "nl_defs.h"
76 #include <libxo/xo.h>
77 
78 static struct protox {
79 	int	pr_index;		/* index into nlist of cb head */
80 	int	pr_sindex;		/* index into nlist of stat block */
81 	u_char	pr_wanted;		/* 1 if wanted, 0 otherwise */
82 	void	(*pr_cblocks)(u_long, const char *, int, int);
83 					/* control blocks printing routine */
84 	void	(*pr_stats)(u_long, const char *, int, int);
85 					/* statistics printing routine */
86 	void	(*pr_istats)(char *);	/* per/if statistics printing routine */
87 	const char	*pr_name;		/* well-known name */
88 	int	pr_usesysctl;		/* non-zero if we use sysctl, not kvm */
89 	int	pr_protocol;
90 } protox[] = {
91 	{ N_TCBINFO,	N_TCPSTAT,	1,	protopr,
92 	  tcp_stats,	NULL,		"tcp",	1,	IPPROTO_TCP },
93 	{ N_UDBINFO,	N_UDPSTAT,	1,	protopr,
94 	  udp_stats,	NULL,		"udp",	1,	IPPROTO_UDP },
95 #ifdef SCTP
96 	{ -1,		N_SCTPSTAT,	1,	sctp_protopr,
97 	  sctp_stats,	NULL,		"sctp",	1,	IPPROTO_SCTP },
98 #endif
99 #ifdef SDP
100 	{ -1,		-1,		1,	protopr,
101 	 NULL,		NULL,		"sdp",	1,	IPPROTO_TCP },
102 #endif
103 	{ N_DIVCBINFO,	-1,		1,	protopr,
104 	  NULL,		NULL,		"divert", 1,	IPPROTO_DIVERT },
105 	{ N_RIPCBINFO,	N_IPSTAT,	1,	protopr,
106 	  ip_stats,	NULL,		"ip",	1,	IPPROTO_RAW },
107 	{ N_RIPCBINFO,	N_ICMPSTAT,	1,	protopr,
108 	  icmp_stats,	NULL,		"icmp",	1,	IPPROTO_ICMP },
109 	{ N_RIPCBINFO,	N_IGMPSTAT,	1,	protopr,
110 	  igmp_stats,	NULL,		"igmp",	1,	IPPROTO_IGMP },
111 #ifdef IPSEC
112 	{ -1,		N_IPSEC4STAT,	1,	NULL,	/* keep as compat */
113 	  ipsec_stats,	NULL,		"ipsec", 1,	0},
114 	{ -1,		N_AHSTAT,	1,	NULL,
115 	  ah_stats,	NULL,		"ah",	1,	0},
116 	{ -1,		N_ESPSTAT,	1,	NULL,
117 	  esp_stats,	NULL,		"esp",	1,	0},
118 	{ -1,		N_IPCOMPSTAT,	1,	NULL,
119 	  ipcomp_stats,	NULL,		"ipcomp", 1,	0},
120 #endif
121 	{ N_RIPCBINFO,	N_PIMSTAT,	1,	protopr,
122 	  pim_stats,	NULL,		"pim",	1,	IPPROTO_PIM },
123 	{ -1,		N_CARPSTATS,	1,	NULL,
124 	  carp_stats,	NULL,		"carp",	1,	0 },
125 #ifdef PF
126 	{ -1,		N_PFSYNCSTATS,	1,	NULL,
127 	  pfsync_stats,	NULL,		"pfsync", 1,	0 },
128 #endif
129 	{ -1,		N_ARPSTAT,	1,	NULL,
130 	  arp_stats,	NULL,		"arp", 1,	0 },
131 	{ -1,		-1,		0,	NULL,
132 	  NULL,		NULL,		NULL,	0,	0 }
133 };
134 
135 #ifdef INET6
136 static struct protox ip6protox[] = {
137 	{ N_TCBINFO,	N_TCPSTAT,	1,	protopr,
138 	  tcp_stats,	NULL,		"tcp",	1,	IPPROTO_TCP },
139 	{ N_UDBINFO,	N_UDPSTAT,	1,	protopr,
140 	  udp_stats,	NULL,		"udp",	1,	IPPROTO_UDP },
141 	{ N_RIPCBINFO,	N_IP6STAT,	1,	protopr,
142 	  ip6_stats,	ip6_ifstats,	"ip6",	1,	IPPROTO_RAW },
143 	{ N_RIPCBINFO,	N_ICMP6STAT,	1,	protopr,
144 	  icmp6_stats,	icmp6_ifstats,	"icmp6", 1,	IPPROTO_ICMPV6 },
145 #ifdef SDP
146 	{ -1,		-1,		1,	protopr,
147 	 NULL,		NULL,		"sdp",	1,	IPPROTO_TCP },
148 #endif
149 #ifdef IPSEC
150 	{ -1,		N_IPSEC6STAT,	1,	NULL,
151 	  ipsec_stats,	NULL,		"ipsec6", 1,	0 },
152 #endif
153 #ifdef notyet
154 	{ -1,		N_PIM6STAT,	1,	NULL,
155 	  pim6_stats,	NULL,		"pim6",	1,	0 },
156 #endif
157 	{ -1,		N_RIP6STAT,	1,	NULL,
158 	  rip6_stats,	NULL,		"rip6",	1,	0 },
159 	{ -1,		-1,		0,	NULL,
160 	  NULL,		NULL,		NULL,	0,	0 }
161 };
162 #endif /*INET6*/
163 
164 #ifdef IPSEC
165 static struct protox pfkeyprotox[] = {
166 	{ -1,		N_PFKEYSTAT,	1,	NULL,
167 	  pfkey_stats,	NULL,		"pfkey", 0,	0 },
168 	{ -1,		-1,		0,	NULL,
169 	  NULL,		NULL,		NULL,	0,	0 }
170 };
171 #endif
172 
173 #ifdef NETGRAPH
174 static struct protox netgraphprotox[] = {
175 	{ N_NGSOCKLIST,	-1,		1,	netgraphprotopr,
176 	  NULL,		NULL,		"ctrl",	0,	0 },
177 	{ N_NGSOCKLIST,	-1,		1,	netgraphprotopr,
178 	  NULL,		NULL,		"data",	0,	0 },
179 	{ -1,		-1,		0,	NULL,
180 	  NULL,		NULL,		NULL,	0,	0 }
181 };
182 #endif
183 
184 static struct protox *protoprotox[] = {
185 					 protox,
186 #ifdef INET6
187 					 ip6protox,
188 #endif
189 #ifdef IPSEC
190 					 pfkeyprotox,
191 #endif
192 					 NULL };
193 
194 static void printproto(struct protox *, const char *, bool *);
195 static void usage(void);
196 static struct protox *name2protox(const char *);
197 static struct protox *knownname(const char *);
198 
199 static int kresolve_list(struct nlist *_nl);
200 
201 static kvm_t *kvmd;
202 static char *nlistf = NULL, *memf = NULL;
203 
204 int	Aflag;		/* show addresses of protocol control block */
205 int	aflag;		/* show all sockets (including servers) */
206 static int	Bflag;		/* show information about bpf consumers */
207 int	bflag;		/* show i/f total bytes in/out */
208 int	dflag;		/* show i/f dropped packets */
209 int	gflag;		/* show group (multicast) routing or stats */
210 int	hflag;		/* show counters in human readable format */
211 int	iflag;		/* show interfaces */
212 int	Lflag;		/* show size of listen queues */
213 int	mflag;		/* show memory stats */
214 int	noutputs = 0;	/* how much outputs before we exit */
215 int	numeric_addr;	/* show addresses numerically */
216 int	numeric_port;	/* show ports numerically */
217 int	Pflag;		/* show TCP log ID */
218 static int pflag;	/* show given protocol */
219 static int	Qflag;		/* show netisr information */
220 int	rflag;		/* show routing tables (or routing stats) */
221 int	Rflag;		/* show flow / RSS statistics */
222 int	sflag;		/* show protocol statistics */
223 int	Wflag;		/* wide display */
224 int	Tflag;		/* TCP Information */
225 int	xflag;		/* extra information, includes all socket buffer info */
226 int	zflag;		/* zero stats */
227 
228 int	interval;	/* repeat interval for i/f stats */
229 
230 char	*interface;	/* desired i/f for stats, or NULL for all i/fs */
231 int	unit;		/* unit number for above */
232 
233 static int	af;		/* address family */
234 int	live;		/* true if we are examining a live system */
235 
236 int
237 main(int argc, char *argv[])
238 {
239 	struct protox *tp = NULL;  /* for printing cblocks & stats */
240 	int ch;
241 	int fib = -1;
242 	char *endptr;
243 	bool first = true;
244 
245 	af = AF_UNSPEC;
246 
247 	argc = xo_parse_args(argc, argv);
248 	if (argc < 0)
249 		exit(EXIT_FAILURE);
250 
251 	while ((ch = getopt(argc, argv, "46AaBbdF:f:ghI:iLlM:mN:nPp:Qq:RrSTsuWw:xz"))
252 	    != -1)
253 		switch(ch) {
254 		case '4':
255 #ifdef INET
256 			af = AF_INET;
257 #else
258 			errx(1, "IPv4 support is not compiled in");
259 #endif
260 			break;
261 		case '6':
262 #ifdef INET6
263 			af = AF_INET6;
264 #else
265 			errx(1, "IPv6 support is not compiled in");
266 #endif
267 			break;
268 		case 'A':
269 			Aflag = 1;
270 			break;
271 		case 'a':
272 			aflag = 1;
273 			break;
274 		case 'B':
275 			Bflag = 1;
276 			break;
277 		case 'b':
278 			bflag = 1;
279 			break;
280 		case 'd':
281 			dflag = 1;
282 			break;
283 		case 'F':
284 			fib = strtol(optarg, &endptr, 0);
285 			if (*endptr != '\0' ||
286 			    (fib == 0 && (errno == EINVAL || errno == ERANGE)))
287 				xo_errx(1, "%s: invalid fib", optarg);
288 			break;
289 		case 'f':
290 			if (strcmp(optarg, "inet") == 0)
291 				af = AF_INET;
292 #ifdef INET6
293 			else if (strcmp(optarg, "inet6") == 0)
294 				af = AF_INET6;
295 #endif
296 #ifdef IPSEC
297 			else if (strcmp(optarg, "pfkey") == 0)
298 				af = PF_KEY;
299 #endif
300 			else if (strcmp(optarg, "unix") == 0 ||
301 				 strcmp(optarg, "local") == 0)
302 				af = AF_UNIX;
303 #ifdef NETGRAPH
304 			else if (strcmp(optarg, "ng") == 0
305 			    || strcmp(optarg, "netgraph") == 0)
306 				af = AF_NETGRAPH;
307 #endif
308 			else if (strcmp(optarg, "link") == 0)
309 				af = AF_LINK;
310 			else {
311 				xo_errx(1, "%s: unknown address family",
312 				    optarg);
313 			}
314 			break;
315 		case 'g':
316 			gflag = 1;
317 			break;
318 		case 'h':
319 			hflag = 1;
320 			break;
321 		case 'I': {
322 			char *cp;
323 
324 			iflag = 1;
325 			for (cp = interface = optarg; isalpha(*cp); cp++)
326 				continue;
327 			unit = atoi(cp);
328 			break;
329 		}
330 		case 'i':
331 			iflag = 1;
332 			break;
333 		case 'L':
334 			Lflag = 1;
335 			break;
336 		case 'M':
337 			memf = optarg;
338 			break;
339 		case 'm':
340 			mflag = 1;
341 			break;
342 		case 'N':
343 			nlistf = optarg;
344 			break;
345 		case 'n':
346 			numeric_addr = numeric_port = 1;
347 			break;
348 		case 'P':
349 			Pflag = 1;
350 			break;
351 		case 'p':
352 			if ((tp = name2protox(optarg)) == NULL) {
353 				xo_errx(1, "%s: unknown or uninstrumented "
354 				    "protocol", optarg);
355 			}
356 			pflag = 1;
357 			break;
358 		case 'Q':
359 			Qflag = 1;
360 			break;
361 		case 'q':
362 			noutputs = atoi(optarg);
363 			if (noutputs != 0)
364 				noutputs++;
365 			break;
366 		case 'r':
367 			rflag = 1;
368 			break;
369 		case 'R':
370 			Rflag = 1;
371 			break;
372 		case 's':
373 			++sflag;
374 			break;
375 		case 'S':
376 			numeric_addr = 1;
377 			break;
378 		case 'u':
379 			af = AF_UNIX;
380 			break;
381 		case 'W':
382 		case 'l':
383 			Wflag = 1;
384 			break;
385 		case 'w':
386 			interval = atoi(optarg);
387 			iflag = 1;
388 			break;
389 		case 'T':
390 			Tflag = 1;
391 			break;
392 		case 'x':
393 			xflag = 1;
394 			break;
395 		case 'z':
396 			zflag = 1;
397 			break;
398 		case '?':
399 		default:
400 			usage();
401 		}
402 	argv += optind;
403 	argc -= optind;
404 
405 #define	BACKWARD_COMPATIBILITY
406 #ifdef	BACKWARD_COMPATIBILITY
407 	if (*argv) {
408 		if (isdigit(**argv)) {
409 			interval = atoi(*argv);
410 			if (interval <= 0)
411 				usage();
412 			++argv;
413 			iflag = 1;
414 		}
415 		if (*argv) {
416 			nlistf = *argv;
417 			if (*++argv)
418 				memf = *argv;
419 		}
420 	}
421 #endif
422 
423 	/*
424 	 * Discard setgid privileges if not the running kernel so that bad
425 	 * guys can't print interesting stuff from kernel memory.
426 	 */
427 	live = (nlistf == NULL && memf == NULL);
428 	if (!live) {
429 		if (setgid(getgid()) != 0)
430 			xo_err(-1, "setgid");
431 		/* Load all necessary kvm symbols */
432 		kresolve_list(nl);
433 	}
434 
435 	if (xflag && Tflag)
436 		xo_errx(1, "-x and -T are incompatible, pick one.");
437 
438 	if (Bflag) {
439 		if (!live)
440 			usage();
441 		bpf_stats(interface);
442 		xo_finish();
443 		exit(0);
444 	}
445 	if (mflag) {
446 		if (!live) {
447 			if (kread(0, NULL, 0) == 0)
448 				mbpr(kvmd, nl[N_SFSTAT].n_value);
449 		} else
450 			mbpr(NULL, 0);
451 		xo_finish();
452 		exit(0);
453 	}
454 	if (Qflag) {
455 		if (!live) {
456 			if (kread(0, NULL, 0) == 0)
457 				netisr_stats();
458 		} else
459 			netisr_stats();
460 		xo_finish();
461 		exit(0);
462 	}
463 #if 0
464 	/*
465 	 * Keep file descriptors open to avoid overhead
466 	 * of open/close on each call to get* routines.
467 	 */
468 	sethostent(1);
469 	setnetent(1);
470 #else
471 	/*
472 	 * This does not make sense any more with DNS being default over
473 	 * the files.  Doing a setXXXXent(1) causes a tcp connection to be
474 	 * used for the queries, which is slower.
475 	 */
476 #endif
477 	if (iflag && !sflag) {
478 		xo_open_container("statistics");
479 		intpr(NULL, af);
480 		xo_close_container("statistics");
481 		xo_finish();
482 		exit(0);
483 	}
484 	if (rflag) {
485 		xo_open_container("statistics");
486 		if (sflag) {
487 			rt_stats();
488 		} else
489 			routepr(fib, af);
490 		xo_close_container("statistics");
491 		xo_finish();
492 		exit(0);
493 	}
494 
495 	if (gflag) {
496 		xo_open_container("statistics");
497 		if (sflag) {
498 			if (af == AF_INET || af == AF_UNSPEC)
499 				mrt_stats();
500 #ifdef INET6
501 			if (af == AF_INET6 || af == AF_UNSPEC)
502 				mrt6_stats();
503 #endif
504 		} else {
505 			if (af == AF_INET || af == AF_UNSPEC)
506 				mroutepr();
507 #ifdef INET6
508 			if (af == AF_INET6 || af == AF_UNSPEC)
509 				mroute6pr();
510 #endif
511 		}
512 		xo_close_container("statistics");
513 		xo_finish();
514 		exit(0);
515 	}
516 
517 	if (tp) {
518 		xo_open_container("statistics");
519 		printproto(tp, tp->pr_name, &first);
520 		if (!first)
521 			xo_close_list("socket");
522 		xo_close_container("statistics");
523 		xo_finish();
524 		exit(0);
525 	}
526 
527 	xo_open_container("statistics");
528 	if (af == AF_INET || af == AF_UNSPEC)
529 		for (tp = protox; tp->pr_name; tp++)
530 			printproto(tp, tp->pr_name, &first);
531 #ifdef INET6
532 	if (af == AF_INET6 || af == AF_UNSPEC)
533 		for (tp = ip6protox; tp->pr_name; tp++)
534 			printproto(tp, tp->pr_name, &first);
535 #endif /*INET6*/
536 #ifdef IPSEC
537 	if (af == PF_KEY || af == AF_UNSPEC)
538 		for (tp = pfkeyprotox; tp->pr_name; tp++)
539 			printproto(tp, tp->pr_name, &first);
540 #endif /*IPSEC*/
541 #ifdef NETGRAPH
542 	if (af == AF_NETGRAPH || af == AF_UNSPEC)
543 		for (tp = netgraphprotox; tp->pr_name; tp++)
544 			printproto(tp, tp->pr_name, &first);
545 #endif /* NETGRAPH */
546 	if ((af == AF_UNIX || af == AF_UNSPEC) && !sflag)
547 		unixpr(nl[N_UNP_COUNT].n_value, nl[N_UNP_GENCNT].n_value,
548 		    nl[N_UNP_DHEAD].n_value, nl[N_UNP_SHEAD].n_value,
549 		    nl[N_UNP_SPHEAD].n_value, &first);
550 
551 	if (!first)
552 		xo_close_list("socket");
553 	xo_close_container("statistics");
554 	xo_finish();
555 	exit(0);
556 }
557 
558 static int
559 fetch_stats_internal(const char *sysctlname, u_long off, void *stats,
560     size_t len, kreadfn_t kreadfn, int zero)
561 {
562 	int error;
563 
564 	if (live) {
565 		memset(stats, 0, len);
566 		if (zero)
567 			error = sysctlbyname(sysctlname, NULL, NULL, stats,
568 			    len);
569 		else
570 			error = sysctlbyname(sysctlname, stats, &len, NULL, 0);
571 		if (error == -1 && errno != ENOENT)
572 			xo_warn("sysctl %s", sysctlname);
573 	} else {
574 		if (off == 0)
575 			return (1);
576 		error = kreadfn(off, stats, len);
577 	}
578 	return (error);
579 }
580 
581 int
582 fetch_stats(const char *sysctlname, u_long off, void *stats,
583     size_t len, kreadfn_t kreadfn)
584 {
585 
586 	return (fetch_stats_internal(sysctlname, off, stats, len, kreadfn,
587     zflag));
588 }
589 
590 int
591 fetch_stats_ro(const char *sysctlname, u_long off, void *stats,
592     size_t len, kreadfn_t kreadfn)
593 {
594 
595 	return (fetch_stats_internal(sysctlname, off, stats, len, kreadfn, 0));
596 }
597 
598 /*
599  * Print out protocol statistics or control blocks (per sflag).
600  * If the interface was not specifically requested, and the symbol
601  * is not in the namelist, ignore this one.
602  */
603 static void
604 printproto(struct protox *tp, const char *name, bool *first)
605 {
606 	void (*pr)(u_long, const char *, int, int);
607 	u_long off;
608 	bool doingdblocks = false;
609 
610 	if (sflag) {
611 		if (iflag) {
612 			if (tp->pr_istats)
613 				intpr(tp->pr_istats, af);
614 			else if (pflag)
615 				xo_message("%s: no per-interface stats routine",
616 				    tp->pr_name);
617 			return;
618 		} else {
619 			pr = tp->pr_stats;
620 			if (!pr) {
621 				if (pflag)
622 					xo_message("%s: no stats routine",
623 					    tp->pr_name);
624 				return;
625 			}
626 			if (tp->pr_usesysctl && live)
627 				off = 0;
628 			else if (tp->pr_sindex < 0) {
629 				if (pflag)
630 					xo_message("%s: stats routine doesn't "
631 					    "work on cores", tp->pr_name);
632 				return;
633 			} else
634 				off = nl[tp->pr_sindex].n_value;
635 		}
636 	} else {
637 		doingdblocks = true;
638 		pr = tp->pr_cblocks;
639 		if (!pr) {
640 			if (pflag)
641 				xo_message("%s: no PCB routine", tp->pr_name);
642 			return;
643 		}
644 		if (tp->pr_usesysctl && live)
645 			off = 0;
646 		else if (tp->pr_index < 0) {
647 			if (pflag)
648 				xo_message("%s: PCB routine doesn't work on "
649 				    "cores", tp->pr_name);
650 			return;
651 		} else
652 			off = nl[tp->pr_index].n_value;
653 	}
654 	if (pr != NULL && (off || (live && tp->pr_usesysctl) ||
655 	    af != AF_UNSPEC)) {
656 		if (doingdblocks && *first) {
657 			xo_open_list("socket");
658 			*first = false;
659 		}
660 
661 		(*pr)(off, name, af, tp->pr_protocol);
662 	}
663 }
664 
665 static int
666 kvmd_init(void)
667 {
668 	char errbuf[_POSIX2_LINE_MAX];
669 
670 	if (kvmd != NULL)
671 		return (0);
672 
673 	kvmd = kvm_openfiles(nlistf, memf, NULL, O_RDONLY, errbuf);
674 	if (setgid(getgid()) != 0)
675 		xo_err(-1, "setgid");
676 
677 	if (kvmd == NULL) {
678 		xo_warnx("kvm not available: %s", errbuf);
679 		return (-1);
680 	}
681 
682 	return (0);
683 }
684 
685 /*
686  * Resolve symbol list, return 0 on success.
687  */
688 static int
689 kresolve_list(struct nlist *_nl)
690 {
691 
692 	if ((kvmd == NULL) && (kvmd_init() != 0))
693 		return (-1);
694 
695 	if (_nl[0].n_type != 0)
696 		return (0);
697 
698 	if (kvm_nlist(kvmd, _nl) < 0) {
699 		if (nlistf)
700 			xo_errx(1, "%s: kvm_nlist: %s", nlistf,
701 			    kvm_geterr(kvmd));
702 		else
703 			xo_errx(1, "kvm_nlist: %s", kvm_geterr(kvmd));
704 	}
705 
706 	return (0);
707 }
708 
709 /*
710  * Wrapper of kvm_dpcpu_setcpu().
711  */
712 void
713 kset_dpcpu(u_int cpuid)
714 {
715 
716 	if ((kvmd == NULL) && (kvmd_init() != 0))
717 		xo_errx(-1, "%s: kvm is not available", __func__);
718 
719 	if (kvm_dpcpu_setcpu(kvmd, cpuid) < 0)
720 		xo_errx(-1, "%s: kvm_dpcpu_setcpu(%u): %s", __func__,
721 		    cpuid, kvm_geterr(kvmd));
722 	return;
723 }
724 
725 /*
726  * Read kernel memory, return 0 on success.
727  */
728 int
729 kread(u_long addr, void *buf, size_t size)
730 {
731 
732 	if (kvmd_init() < 0)
733 		return (-1);
734 
735 	if (!buf)
736 		return (0);
737 	if (kvm_read(kvmd, addr, buf, size) != (ssize_t)size) {
738 		xo_warnx("%s", kvm_geterr(kvmd));
739 		return (-1);
740 	}
741 	return (0);
742 }
743 
744 /*
745  * Read single counter(9).
746  */
747 uint64_t
748 kread_counter(u_long addr)
749 {
750 
751 	if (kvmd_init() < 0)
752 		return (-1);
753 
754 	return (kvm_counter_u64_fetch(kvmd, addr));
755 }
756 
757 /*
758  * Read an array of N counters in kernel memory into array of N uint64_t's.
759  */
760 int
761 kread_counters(u_long addr, void *buf, size_t size)
762 {
763 	uint64_t *c;
764 	u_long *counters;
765 	size_t i, n;
766 
767 	if (kvmd_init() < 0)
768 		return (-1);
769 
770 	if (size % sizeof(uint64_t) != 0) {
771 		xo_warnx("kread_counters: invalid counter set size");
772 		return (-1);
773 	}
774 
775 	n = size / sizeof(uint64_t);
776 	if ((counters = malloc(n * sizeof(u_long))) == NULL)
777 		xo_err(-1, "malloc");
778 	if (kread(addr, counters, n * sizeof(u_long)) < 0) {
779 		free(counters);
780 		return (-1);
781 	}
782 
783 	c = buf;
784 	for (i = 0; i < n; i++)
785 		c[i] = kvm_counter_u64_fetch(kvmd, counters[i]);
786 
787 	free(counters);
788 	return (0);
789 }
790 
791 const char *
792 plural(uintmax_t n)
793 {
794 	return (n != 1 ? "s" : "");
795 }
796 
797 const char *
798 plurales(uintmax_t n)
799 {
800 	return (n != 1 ? "es" : "");
801 }
802 
803 const char *
804 pluralies(uintmax_t n)
805 {
806 	return (n != 1 ? "ies" : "y");
807 }
808 
809 /*
810  * Find the protox for the given "well-known" name.
811  */
812 static struct protox *
813 knownname(const char *name)
814 {
815 	struct protox **tpp, *tp;
816 
817 	for (tpp = protoprotox; *tpp; tpp++)
818 		for (tp = *tpp; tp->pr_name; tp++)
819 			if (strcmp(tp->pr_name, name) == 0)
820 				return (tp);
821 	return (NULL);
822 }
823 
824 /*
825  * Find the protox corresponding to name.
826  */
827 static struct protox *
828 name2protox(const char *name)
829 {
830 	struct protox *tp;
831 	char **alias;			/* alias from p->aliases */
832 	struct protoent *p;
833 
834 	/*
835 	 * Try to find the name in the list of "well-known" names. If that
836 	 * fails, check if name is an alias for an Internet protocol.
837 	 */
838 	if ((tp = knownname(name)) != NULL)
839 		return (tp);
840 
841 	setprotoent(1);			/* make protocol lookup cheaper */
842 	while ((p = getprotoent()) != NULL) {
843 		/* assert: name not same as p->name */
844 		for (alias = p->p_aliases; *alias; alias++)
845 			if (strcmp(name, *alias) == 0) {
846 				endprotoent();
847 				return (knownname(p->p_name));
848 			}
849 	}
850 	endprotoent();
851 	return (NULL);
852 }
853 
854 static void
855 usage(void)
856 {
857 	(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",
858 "usage: netstat [-46AaLnRSTWx] [-f protocol_family | -p protocol]\n"
859 "               [-M core] [-N system]",
860 "       netstat -i | -I interface [-46abdhnW] [-f address_family]\n"
861 "               [-M core] [-N system]",
862 "       netstat -w wait [-I interface] [-46d] [-M core] [-N system]\n"
863 "               [-q howmany]",
864 "       netstat -s [-46sz] [-f protocol_family | -p protocol]\n"
865 "               [-M core] [-N system]",
866 "       netstat -i | -I interface -s [-46s]\n"
867 "               [-f protocol_family | -p protocol] [-M core] [-N system]",
868 "       netstat -m [-M core] [-N system]",
869 "       netstat -B [-z] [-I interface]",
870 "       netstat -r [-46AnW] [-F fibnum] [-f address_family]\n"
871 "               [-M core] [-N system]",
872 "       netstat -rs [-s] [-M core] [-N system]",
873 "       netstat -g [-46W] [-f address_family] [-M core] [-N system]",
874 "       netstat -gs [-46s] [-f address_family] [-M core] [-N system]",
875 "       netstat -Q");
876 	xo_finish();
877 	exit(1);
878 }
879