xref: /freebsd/usr.bin/netstat/main.c (revision 6780ab54325a71e7e70112b11657973edde8655e)
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. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifndef lint
35 char const copyright[] =
36 "@(#) Copyright (c) 1983, 1988, 1993\n\
37 	Regents of the University of California.  All rights reserved.\n";
38 #endif /* not lint */
39 
40 #ifndef lint
41 #if 0
42 static char sccsid[] = "@(#)main.c	8.4 (Berkeley) 3/1/94";
43 #endif
44 static const char rcsid[] =
45   "$FreeBSD$";
46 #endif /* not lint */
47 
48 #include <sys/param.h>
49 #include <sys/file.h>
50 #include <sys/protosw.h>
51 #include <sys/socket.h>
52 
53 #include <netinet/in.h>
54 
55 #include <netgraph/ng_socket.h>
56 
57 #include <ctype.h>
58 #include <err.h>
59 #include <errno.h>
60 #include <kvm.h>
61 #include <limits.h>
62 #include <netdb.h>
63 #include <nlist.h>
64 #include <paths.h>
65 #include <stdio.h>
66 #include <stdlib.h>
67 #include <string.h>
68 #include <unistd.h>
69 #include "netstat.h"
70 
71 static struct nlist nl[] = {
72 #define	N_IFNET		0
73 	{ "_ifnet" },
74 #define	N_IMP		1
75 	{ "_imp_softc" },
76 #define	N_RTSTAT	2
77 	{ "_rtstat" },
78 #define	N_UNIXSW	3
79 	{ "_localsw" },
80 #define N_IDP		4
81 	{ "_nspcb"},
82 #define N_IDPSTAT	5
83 	{ "_idpstat"},
84 #define N_SPPSTAT	6
85 	{ "_spp_istat"},
86 #define N_NSERR		7
87 	{ "_ns_errstat"},
88 #define	N_CLNPSTAT	8
89 	{ "_clnp_stat"},
90 #define	IN_NOTUSED	9
91 	{ "_tp_inpcb" },
92 #define	ISO_TP		10
93 	{ "_tp_refinfo" },
94 #define	N_TPSTAT	11
95 	{ "_tp_stat" },
96 #define	N_ESISSTAT	12
97 	{ "_esis_stat"},
98 #define N_NIMP		13
99 	{ "_nimp"},
100 #define N_RTREE		14
101 	{ "_rt_tables"},
102 #define N_CLTP		15
103 	{ "_cltb"},
104 #define N_CLTPSTAT	16
105 	{ "_cltpstat"},
106 #define	N_NFILE		17
107 	{ "_nfile" },
108 #define	N_FILE		18
109 	{ "_file" },
110 #define N_MRTSTAT	19
111 	{ "_mrtstat" },
112 #define N_MFCTABLE	20
113 	{ "_mfctable" },
114 #define N_VIFTABLE	21
115 	{ "_viftable" },
116 #define N_IPX		22
117 	{ "_ipxpcb"},
118 #define N_IPXSTAT	23
119 	{ "_ipxstat"},
120 #define N_SPXSTAT	24
121 	{ "_spx_istat"},
122 #define N_DDPSTAT	25
123 	{ "_ddpstat"},
124 #define N_DDPCB		26
125 	{ "_ddpcb"},
126 #define N_NGSOCKS	27
127 	{ "_ngsocklist"},
128 #define N_IP6STAT	28
129 	{ "_ip6stat" },
130 #define N_ICMP6STAT	29
131 	{ "_icmp6stat" },
132 #define N_IPSECSTAT	30
133 	{ "_ipsecstat" },
134 #define N_IPSEC6STAT	31
135 	{ "_ipsec6stat" },
136 #define N_PIM6STAT	32
137 	{ "_pim6stat" },
138 #define N_MRT6PROTO	33
139 	{ "_ip6_mrtproto" },
140 #define N_MRT6STAT	34
141 	{ "_mrt6stat" },
142 #define N_MF6CTABLE	35
143 	{ "_mf6ctable" },
144 #define N_MIF6TABLE	36
145 	{ "_mif6table" },
146 #define N_PFKEYSTAT	37
147 	{ "_pfkeystat" },
148 #define N_MBSTAT	38
149 	{ "_mbstat" },
150 #define N_MBTYPES	39
151 	{ "_mbtypes" },
152 #define N_NMBCLUSTERS	40
153 	{ "_nmbclusters" },
154 #define N_NMBUFS	41
155 	{ "_nmbufs" },
156 #define	N_MBLIM		42
157 	{ "_mbuf_limit" },
158 #define	N_CLLIM		43
159 	{ "_clust_limit" },
160 #define	N_NCPUS		44
161 	{ "_smp_cpus" },
162 #define	N_PAGESZ	45
163 	{ "_pagesize" },
164 #define	N_MBPSTAT	46
165 	{ "_mb_statpcpu" },
166 #define	N_RTTRASH	47
167 	{ "_rttrash" },
168 	{ "" },
169 };
170 
171 struct protox {
172 	u_char	pr_index;		/* index into nlist of cb head */
173 	u_char	pr_sindex;		/* index into nlist of stat block */
174 	u_char	pr_wanted;		/* 1 if wanted, 0 otherwise */
175 	void	(*pr_cblocks)(u_long, const char *, int);
176 					/* control blocks printing routine */
177 	void	(*pr_stats)(u_long, const char *, int);
178 					/* statistics printing routine */
179 	void	(*pr_istats)(char *);	/* per/if statistics printing routine */
180 	const char	*pr_name;		/* well-known name */
181 	u_long	pr_usesysctl;		/* true if we use sysctl, not kvm */
182 } protox[] = {
183 	{ -1,		-1,		1,	protopr,
184 	  tcp_stats,	NULL,		"tcp",	IPPROTO_TCP },
185 	{ -1,		-1,		1,	protopr,
186 	  udp_stats,	NULL,		"udp",	IPPROTO_UDP },
187 	{ -1,		-1,		1,	protopr,
188 	  NULL,		NULL,		"divert",IPPROTO_DIVERT },
189 	{ -1,		-1,		1,	protopr,
190 	  ip_stats,	NULL,		"ip",	IPPROTO_RAW },
191 	{ -1,		-1,		1,	protopr,
192 	  icmp_stats,	NULL,		"icmp",	IPPROTO_ICMP },
193 	{ -1,		-1,		1,	protopr,
194 	  igmp_stats,	NULL,		"igmp",	IPPROTO_IGMP },
195 #ifdef IPSEC
196 	{ -1,		N_IPSECSTAT,	1,	0,
197 	  ipsec_stats,	NULL,		"ipsec",	0},
198 #endif
199 	{ -1,		-1,		1,	0,
200 	  bdg_stats,	NULL,		"bdg",	1 /* bridging... */ },
201 	{ -1,		-1,		0,	0,
202 	  0,		NULL,		0,	0 }
203 };
204 
205 #ifdef INET6
206 struct protox ip6protox[] = {
207 	{ -1,		-1,		1,	protopr,
208 	  tcp_stats,	NULL,		"tcp",	IPPROTO_TCP },
209 	{ -1,		-1,		1,	protopr,
210 	  udp_stats,	NULL,		"udp",	IPPROTO_UDP },
211 	{ -1,		N_IP6STAT,	1,	protopr,
212 	  ip6_stats,	ip6_ifstats,	"ip6",	IPPROTO_RAW },
213 	{ -1,		N_ICMP6STAT,	1,	protopr,
214 	  icmp6_stats,	icmp6_ifstats,	"icmp6",IPPROTO_ICMPV6 },
215 #ifdef IPSEC
216 	{ -1,		N_IPSEC6STAT,	1,	0,
217 	  ipsec_stats,	NULL,		"ipsec6",0 },
218 #endif
219 #ifdef notyet
220 	{ -1,		N_PIM6STAT,	1,	0,
221 	  pim6_stats,	NULL,		"pim6",	0 },
222 #endif
223 	{ -1,		-1,		1,	0,
224 	  rip6_stats,	NULL,		"rip6",	0 },
225 	{ -1,		-1,		1,	0,
226 	  bdg_stats,	NULL,		"bdg",	1 /* bridging... */ },
227 	{ -1,		-1,		0,	0,
228 	  0,		NULL,		0,	0 }
229 };
230 #endif /*INET6*/
231 
232 #ifdef IPSEC
233 struct protox pfkeyprotox[] = {
234 	{ -1,		N_PFKEYSTAT,	1,	0,
235 	  pfkey_stats,	NULL,		"pfkey", 0 },
236 	{ -1,		-1,		0,	0,
237 	  0,		NULL,		0,	0 }
238 };
239 #endif
240 
241 struct protox atalkprotox[] = {
242 	{ N_DDPCB,	N_DDPSTAT,	1,	atalkprotopr,
243 	  ddp_stats,	NULL,		"ddp",	0 },
244 	{ -1,		-1,		0,	0,
245 	  0,		NULL,		0,	0 }
246 };
247 
248 struct protox netgraphprotox[] = {
249 	{ N_NGSOCKS,	-1,		1,	netgraphprotopr,
250 	  NULL,		NULL,		"ctrl",	0 },
251 	{ N_NGSOCKS,	-1,		1,	netgraphprotopr,
252 	  NULL,		NULL,		"data",	0 },
253 	{ -1,		NULL,		0,	0,
254 	  0,		NULL,		0,	0 }
255 };
256 
257 struct protox ipxprotox[] = {
258 	{ N_IPX,	N_IPXSTAT,	1,	ipxprotopr,
259 	  ipx_stats,	NULL,		"ipx",	0 },
260 	{ N_IPX,	N_SPXSTAT,	1,	ipxprotopr,
261 	  spx_stats,	NULL,		"spx",	0 },
262 	{ -1,		-1,		0,	0,
263 	  0,		NULL,		0,	0 }
264 };
265 
266 #ifdef NS
267 struct protox nsprotox[] = {
268 	{ N_IDP,	N_IDPSTAT,	1,	nsprotopr,
269 	  idp_stats,	NULL,		"idp" },
270 	{ N_IDP,	N_SPPSTAT,	1,	nsprotopr,
271 	  spp_stats,	NULL,		"spp" },
272 	{ -1,		N_NSERR,	1,	0,
273 	  nserr_stats,	NULL,		"ns_err" },
274 	{ -1,		-1,		0,	0,
275 	  0,		NULL,		0 }
276 };
277 #endif
278 
279 #ifdef ISO
280 struct protox isoprotox[] = {
281 	{ ISO_TP,	N_TPSTAT,	1,	iso_protopr,
282 	  tp_stats,	NULL,		"tp" },
283 	{ N_CLTP,	N_CLTPSTAT,	1,	iso_protopr,
284 	  cltp_stats,	NULL,		"cltp" },
285 	{ -1,		N_CLNPSTAT,	1,	 0,
286 	  clnp_stats,	NULL,		"clnp"},
287 	{ -1,		N_ESISSTAT,	1,	 0,
288 	  esis_stats,	NULL,		"esis"},
289 	{ -1,		-1,		0,	0,
290 	  0,		NULL,		0 }
291 };
292 #endif
293 
294 struct protox *protoprotox[] = {
295 					 protox,
296 #ifdef INET6
297 					 ip6protox,
298 #endif
299 #ifdef IPSEC
300 					 pfkeyprotox,
301 #endif
302 					 ipxprotox, atalkprotox,
303 #ifdef NS
304 					 nsprotox,
305 #endif
306 #ifdef ISO
307 					 isoprotox,
308 #endif
309 					 NULL };
310 
311 static void printproto (struct protox *, const char *);
312 static void usage (void);
313 static struct protox *name2protox (char *);
314 static struct protox *knownname (char *);
315 
316 static kvm_t *kvmd;
317 static char *nlistf = NULL, *memf = NULL;
318 
319 int	Aflag;		/* show addresses of protocol control block */
320 int	aflag;		/* show all sockets (including servers) */
321 int	bflag;		/* show i/f total bytes in/out */
322 int	dflag;		/* show i/f dropped packets */
323 int	gflag;		/* show group (multicast) routing or stats */
324 int	iflag;		/* show interfaces */
325 int	Lflag;		/* show size of listen queues */
326 int	mflag;		/* show memory stats */
327 int	numeric_addr;	/* show addresses numerically */
328 int	numeric_port;	/* show ports numerically */
329 static int pflag;	/* show given protocol */
330 int	rflag;		/* show routing tables (or routing stats) */
331 int	sflag;		/* show protocol statistics */
332 int	tflag;		/* show i/f watchdog timers */
333 int	Wflag;		/* wide display */
334 int	zflag;		/* zero stats */
335 
336 int	interval;	/* repeat interval for i/f stats */
337 
338 char	*interface;	/* desired i/f for stats, or NULL for all i/fs */
339 int	unit;		/* unit number for above */
340 
341 int	af;		/* address family */
342 
343 int
344 main(int argc, char *argv[])
345 {
346 	struct protox *tp = NULL;  /* for printing cblocks & stats */
347 	int ch;
348 
349 	af = AF_UNSPEC;
350 
351 	while ((ch = getopt(argc, argv, "Aabdf:gI:iLlM:mN:np:rSstuWw:z")) != -1)
352 		switch(ch) {
353 		case 'A':
354 			Aflag = 1;
355 			break;
356 		case 'a':
357 			aflag = 1;
358 			break;
359 		case 'b':
360 			bflag = 1;
361 			break;
362 		case 'd':
363 			dflag = 1;
364 			break;
365 		case 'f':
366 #ifdef NS
367 			if (strcmp(optarg, "ns") == 0)
368 				af = AF_NS;
369 			else
370 #endif
371 			if (strcmp(optarg, "ipx") == 0)
372 				af = AF_IPX;
373 			else if (strcmp(optarg, "inet") == 0)
374 				af = AF_INET;
375 #ifdef INET6
376 			else if (strcmp(optarg, "inet6") == 0)
377 				af = AF_INET6;
378 #endif /*INET6*/
379 #ifdef INET6
380 			else if (strcmp(optarg, "pfkey") == 0)
381 				af = PF_KEY;
382 #endif /*INET6*/
383 			else if (strcmp(optarg, "unix") == 0)
384 				af = AF_UNIX;
385 			else if (strcmp(optarg, "atalk") == 0)
386 				af = AF_APPLETALK;
387 			else if (strcmp(optarg, "ng") == 0
388 			    || strcmp(optarg, "netgraph") == 0)
389 				af = AF_NETGRAPH;
390 #ifdef ISO
391 			else if (strcmp(optarg, "iso") == 0)
392 				af = AF_ISO;
393 #endif
394 			else if (strcmp(optarg, "link") == 0)
395 				af = AF_LINK;
396 			else {
397 				errx(1, "%s: unknown address family", optarg);
398 			}
399 			break;
400 		case 'g':
401 			gflag = 1;
402 			break;
403 		case 'I': {
404 			char *cp;
405 
406 			iflag = 1;
407 			for (cp = interface = optarg; isalpha(*cp); cp++)
408 				continue;
409 			unit = atoi(cp);
410 			break;
411 		}
412 		case 'i':
413 			iflag = 1;
414 			break;
415 		case 'L':
416 			Lflag = 1;
417 			break;
418 		case 'M':
419 			memf = optarg;
420 			break;
421 		case 'm':
422 			mflag = 1;
423 			break;
424 		case 'N':
425 			nlistf = optarg;
426 			break;
427 		case 'n':
428 			numeric_addr = numeric_port = 1;
429 			break;
430 		case 'p':
431 			if ((tp = name2protox(optarg)) == NULL) {
432 				errx(1,
433 				     "%s: unknown or uninstrumented protocol",
434 				     optarg);
435 			}
436 			pflag = 1;
437 			break;
438 		case 'r':
439 			rflag = 1;
440 			break;
441 		case 's':
442 			++sflag;
443 			break;
444 		case 'S':
445 			numeric_addr = 1;
446 			break;
447 		case 't':
448 			tflag = 1;
449 			break;
450 		case 'u':
451 			af = AF_UNIX;
452 			break;
453 		case 'W':
454 		case 'l':
455 			Wflag = 1;
456 			break;
457 		case 'w':
458 			interval = atoi(optarg);
459 			iflag = 1;
460 			break;
461 		case 'z':
462 			zflag = 1;
463 			break;
464 		case '?':
465 		default:
466 			usage();
467 		}
468 	argv += optind;
469 	argc -= optind;
470 
471 #define	BACKWARD_COMPATIBILITY
472 #ifdef	BACKWARD_COMPATIBILITY
473 	if (*argv) {
474 		if (isdigit(**argv)) {
475 			interval = atoi(*argv);
476 			if (interval <= 0)
477 				usage();
478 			++argv;
479 			iflag = 1;
480 		}
481 		if (*argv) {
482 			nlistf = *argv;
483 			if (*++argv)
484 				memf = *argv;
485 		}
486 	}
487 #endif
488 
489 	/*
490 	 * Discard setgid privileges if not the running kernel so that bad
491 	 * guys can't print interesting stuff from kernel memory.
492 	 */
493 	if (nlistf != NULL || memf != NULL)
494 		setgid(getgid());
495 
496 	if (mflag) {
497 		if (memf != NULL) {
498 			if (kread(0, 0, 0) == 0)
499 				mbpr(nl[N_MBSTAT].n_value,
500 				    nl[N_MBTYPES].n_value,
501 				    nl[N_NMBCLUSTERS].n_value,
502 				    nl[N_NMBUFS].n_value,
503 				    nl[N_MBLIM].n_value,
504 				    nl[N_CLLIM].n_value,
505 				    nl[N_NCPUS].n_value,
506 				    nl[N_PAGESZ].n_value,
507 				    nl[N_MBPSTAT].n_value);
508 		} else
509 			mbpr(0, 0, 0, 0, 0, 0, 0, 0, 0);
510 		exit(0);
511 	}
512 #if 0
513 	/*
514 	 * Keep file descriptors open to avoid overhead
515 	 * of open/close on each call to get* routines.
516 	 */
517 	sethostent(1);
518 	setnetent(1);
519 #else
520 	/*
521 	 * This does not make sense any more with DNS being default over
522 	 * the files.  Doing a setXXXXent(1) causes a tcp connection to be
523 	 * used for the queries, which is slower.
524 	 */
525 #endif
526 	if (iflag && !sflag) {
527 		kread(0, 0, 0);
528 		intpr(interval, nl[N_IFNET].n_value, NULL);
529 		exit(0);
530 	}
531 	if (rflag) {
532 		kread(0, 0, 0);
533 		if (sflag)
534 			rt_stats(nl[N_RTSTAT].n_value, nl[N_RTTRASH].n_value);
535 		else
536 			routepr(nl[N_RTREE].n_value);
537 		exit(0);
538 	}
539 	if (gflag) {
540 		kread(0, 0, 0);
541 		if (sflag) {
542 			if (af == AF_INET || af == AF_UNSPEC)
543 				mrt_stats(nl[N_MRTSTAT].n_value);
544 #ifdef INET6
545 			if (af == AF_INET6 || af == AF_UNSPEC)
546 				mrt6_stats(nl[N_MRT6STAT].n_value);
547 #endif
548 		} else {
549 			if (af == AF_INET || af == AF_UNSPEC)
550 				mroutepr(nl[N_MFCTABLE].n_value,
551 					 nl[N_VIFTABLE].n_value);
552 #ifdef INET6
553 			if (af == AF_INET6 || af == AF_UNSPEC)
554 				mroute6pr(nl[N_MF6CTABLE].n_value,
555 					  nl[N_MIF6TABLE].n_value);
556 #endif
557 		}
558 		exit(0);
559 	}
560 
561 	kread(0, 0, 0);
562 	if (tp) {
563 		printproto(tp, tp->pr_name);
564 		exit(0);
565 	}
566 	if (af == AF_INET || af == AF_UNSPEC)
567 		for (tp = protox; tp->pr_name; tp++)
568 			printproto(tp, tp->pr_name);
569 #ifdef INET6
570 	if (af == AF_INET6 || af == AF_UNSPEC)
571 		for (tp = ip6protox; tp->pr_name; tp++)
572 			printproto(tp, tp->pr_name);
573 #endif /*INET6*/
574 #ifdef IPSEC
575 	if (af == PF_KEY || af == AF_UNSPEC)
576 		for (tp = pfkeyprotox; tp->pr_name; tp++)
577 			printproto(tp, tp->pr_name);
578 #endif /*IPSEC*/
579 	if (af == AF_IPX || af == AF_UNSPEC) {
580 		kread(0, 0, 0);
581 		for (tp = ipxprotox; tp->pr_name; tp++)
582 			printproto(tp, tp->pr_name);
583 	}
584 	if (af == AF_APPLETALK || af == AF_UNSPEC)
585 		for (tp = atalkprotox; tp->pr_name; tp++)
586 			printproto(tp, tp->pr_name);
587 	if (af == AF_NETGRAPH || af == AF_UNSPEC)
588 		for (tp = netgraphprotox; tp->pr_name; tp++)
589 			printproto(tp, tp->pr_name);
590 #ifdef NS
591 	if (af == AF_NS || af == AF_UNSPEC)
592 		for (tp = nsprotox; tp->pr_name; tp++)
593 			printproto(tp, tp->pr_name);
594 #endif
595 #ifdef ISO
596 	if (af == AF_ISO || af == AF_UNSPEC)
597 		for (tp = isoprotox; tp->pr_name; tp++)
598 			printproto(tp, tp->pr_name);
599 #endif
600 	if ((af == AF_UNIX || af == AF_UNSPEC) && !Lflag && !sflag)
601 		unixpr();
602 	exit(0);
603 }
604 
605 /*
606  * Print out protocol statistics or control blocks (per sflag).
607  * If the interface was not specifically requested, and the symbol
608  * is not in the namelist, ignore this one.
609  */
610 static void
611 printproto(tp, name)
612 	struct protox *tp;
613 	const char *name;
614 {
615 	void (*pr)(u_long, const char *, int);
616 	u_long off;
617 
618 	if (sflag) {
619 		if (iflag) {
620 			if (tp->pr_istats)
621 				intpr(interval, nl[N_IFNET].n_value,
622 				      tp->pr_istats);
623 			else if (pflag)
624 				printf("%s: no per-interface stats routine\n",
625 				    tp->pr_name);
626 			return;
627 		}
628 		else {
629 			pr = tp->pr_stats;
630 			if (!pr) {
631 				if (pflag)
632 					printf("%s: no stats routine\n",
633 					    tp->pr_name);
634 				return;
635 			}
636 			off = tp->pr_usesysctl ? tp->pr_usesysctl
637 				: nl[tp->pr_sindex].n_value;
638 		}
639 	} else {
640 		pr = tp->pr_cblocks;
641 		if (!pr) {
642 			if (pflag)
643 				printf("%s: no PCB routine\n", tp->pr_name);
644 			return;
645 		}
646 		off = tp->pr_usesysctl ? tp->pr_usesysctl
647 			: nl[tp->pr_index].n_value;
648 	}
649 	if (pr != NULL && (off || af != AF_UNSPEC))
650 		(*pr)(off, name, af);
651 }
652 
653 /*
654  * Read kernel memory, return 0 on success.
655  */
656 int
657 kread(u_long addr, char *buf, int size)
658 {
659 	if (kvmd == 0) {
660 		/*
661 		 * XXX.
662 		 */
663 		kvmd = kvm_openfiles(nlistf, memf, NULL, O_RDONLY, buf);
664 		setgid(getgid());
665 		if (kvmd != NULL) {
666 			if (kvm_nlist(kvmd, nl) < 0) {
667 				if(nlistf)
668 					errx(1, "%s: kvm_nlist: %s", nlistf,
669 					     kvm_geterr(kvmd));
670 				else
671 					errx(1, "kvm_nlist: %s", kvm_geterr(kvmd));
672 			}
673 
674 			if (nl[0].n_type == 0) {
675 				if(nlistf)
676 					errx(1, "%s: no namelist", nlistf);
677 				else
678 					errx(1, "no namelist");
679 			}
680 		} else {
681 			warnx("kvm not available");
682 			return(-1);
683 		}
684 	}
685 	if (!buf)
686 		return (0);
687 	if (kvm_read(kvmd, addr, buf, size) != size) {
688 		warnx("%s", kvm_geterr(kvmd));
689 		return (-1);
690 	}
691 	return (0);
692 }
693 
694 const char *
695 plural(int n)
696 {
697 	return (n != 1 ? "s" : "");
698 }
699 
700 const char *
701 plurales(int n)
702 {
703 	return (n != 1 ? "es" : "");
704 }
705 
706 const char *
707 pluralies(int n)
708 {
709 	return (n != 1 ? "ies" : "y");
710 }
711 
712 /*
713  * Find the protox for the given "well-known" name.
714  */
715 static struct protox *
716 knownname(char *name)
717 {
718 	struct protox **tpp, *tp;
719 
720 	for (tpp = protoprotox; *tpp; tpp++)
721 		for (tp = *tpp; tp->pr_name; tp++)
722 			if (strcmp(tp->pr_name, name) == 0)
723 				return (tp);
724 	return (NULL);
725 }
726 
727 /*
728  * Find the protox corresponding to name.
729  */
730 static struct protox *
731 name2protox(char *name)
732 {
733 	struct protox *tp;
734 	char **alias;			/* alias from p->aliases */
735 	struct protoent *p;
736 
737 	/*
738 	 * Try to find the name in the list of "well-known" names. If that
739 	 * fails, check if name is an alias for an Internet protocol.
740 	 */
741 	if ((tp = knownname(name)) != NULL)
742 		return (tp);
743 
744 	setprotoent(1);			/* make protocol lookup cheaper */
745 	while ((p = getprotoent()) != NULL) {
746 		/* assert: name not same as p->name */
747 		for (alias = p->p_aliases; *alias; alias++)
748 			if (strcmp(name, *alias) == 0) {
749 				endprotoent();
750 				return (knownname(p->p_name));
751 			}
752 	}
753 	endprotoent();
754 	return (NULL);
755 }
756 
757 static void
758 usage(void)
759 {
760 	(void)fprintf(stderr, "%s\n%s\n%s\n%s\n%s\n%s\n%s\n%s\n%s\n%s\n",
761 "usage: netstat [-AaLnSW] [-f protocol_family | -p protocol]\n"
762 "               [-M core] [-N system]",
763 "       netstat -i | -I interface [-abdnt] [-f address_family]\n"
764 "               [-M core] [-N system]",
765 "       netstat -w wait [-I interface] [-d] [-M core] [-N system]",
766 "       netstat -s [-s] [-z] [-f protocol_family | -p protocol] [-M core]",
767 "       netstat -i | -I interface -s [-f protocol_family | -p protocol]\n"
768 "               [-M core] [-N system]",
769 "       netstat -m [-M core] [-N system]",
770 "       netstat -r [-AanW] [-f address_family] [-M core] [-N system]",
771 "       netstat -rs [-s] [-M core] [-N system]",
772 "       netstat -g [-W] [-f address_family] [-M core] [-N system]",
773 "       netstat -gs [-s] [-f address_family] [-M core] [-N system]");
774 	exit(1);
775 }
776