xref: /netbsd/usr.bin/netstat/main.c (revision bf9ec67e)
1 /*	$NetBSD: main.c,v 1.34 2001/10/18 09:26:16 itojun Exp $	*/
2 
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. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <sys/cdefs.h>
37 #ifndef lint
38 __COPYRIGHT("@(#) Copyright (c) 1983, 1988, 1993\n\
39 	Regents of the University of California.  All rights reserved.\n");
40 #endif /* not lint */
41 
42 #ifndef lint
43 #if 0
44 static char sccsid[] = "from: @(#)main.c	8.4 (Berkeley) 3/1/94";
45 #else
46 __RCSID("$NetBSD: main.c,v 1.34 2001/10/18 09:26:16 itojun Exp $");
47 #endif
48 #endif /* not lint */
49 
50 #include <sys/param.h>
51 #include <sys/file.h>
52 #include <sys/protosw.h>
53 #include <sys/socket.h>
54 
55 #include <netinet/in.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 struct nlist nl[] = {
72 #define	N_MBSTAT	0
73 	{ "_mbstat" },
74 #define	N_IPSTAT	1
75 	{ "_ipstat" },
76 #define	N_TCBTABLE	2
77 	{ "_tcbtable" },
78 #define	N_TCPSTAT	3
79 	{ "_tcpstat" },
80 #define	N_UDBTABLE	4
81 	{ "_udbtable" },
82 #define	N_UDPSTAT	5
83 	{ "_udpstat" },
84 #define	N_IFNET		6
85 	{ "_ifnet" },
86 #define	N_IMP		7
87 	{ "_imp_softc" },
88 #define	N_ICMPSTAT	8
89 	{ "_icmpstat" },
90 #define	N_RTSTAT	9
91 	{ "_rtstat" },
92 #define	N_UNIXSW	10
93 	{ "_unixsw" },
94 #define N_IDP		11
95 	{ "_nspcb"},
96 #define N_IDPSTAT	12
97 	{ "_idpstat"},
98 #define N_SPPSTAT	13
99 	{ "_spp_istat"},
100 #define N_NSERR		14
101 	{ "_ns_errstat"},
102 #define	N_CLNPSTAT	15
103 	{ "_clnp_stat"},
104 #define	IN_NOTUSED	16
105 	{ "_tp_inpcb" },
106 #define	ISO_TP		17
107 	{ "_tp_refinfo" },
108 #define	N_TPSTAT	18
109 	{ "_tp_stat" },
110 #define	N_ESISSTAT	19
111 	{ "_esis_stat"},
112 #define N_NIMP		20
113 	{ "_nimp"},
114 #define N_RTREE		21
115 	{ "_rt_tables"},
116 #define N_CLTP		22
117 	{ "_cltb"},
118 #define N_CLTPSTAT	23
119 	{ "_cltpstat"},
120 #define	N_NFILE		24
121 	{ "_nfile" },
122 #define	N_FILE		25
123 	{ "_file" },
124 #define N_IGMPSTAT	26
125 	{ "_igmpstat" },
126 #define N_MRTPROTO	27
127 	{ "_ip_mrtproto" },
128 #define N_MRTSTAT	28
129 	{ "_mrtstat" },
130 #define N_MFCHASHTBL	29
131 	{ "_mfchashtbl" },
132 #define	N_MFCHASH	30
133 	{ "_mfchash" },
134 #define N_VIFTABLE	31
135 	{ "_viftable" },
136 #define N_MSIZE		32
137 	{ "_msize" },
138 #define N_MCLBYTES	33
139 	{ "_mclbytes" },
140 #define N_DDPSTAT	34
141 	{ "_ddpstat"},
142 #define N_DDPCB		35
143 	{ "_ddpcb"},
144 #define N_MBPOOL	36
145 	{ "_mbpool" },
146 #define N_MCLPOOL	37
147 	{ "_mclpool" },
148 #define N_DIVPCB	38
149 	{ "_divcb"},
150 #define N_DIVSTAT	39
151 	{ "_divstat"},
152 #define N_IP6STAT	40
153 	{ "_ip6stat" },
154 #define N_TCB6		41
155 	{ "_tcb6" },
156 #define N_TCP6STAT	42
157 	{ "_tcp6stat" },
158 #define N_UDB6		43
159 	{ "_udb6" },
160 #define N_UDP6STAT	44
161 	{ "_udp6stat" },
162 #define N_ICMP6STAT	45
163 	{ "_icmp6stat" },
164 #define N_IPSECSTAT	46
165 	{ "_ipsecstat" },
166 #define N_IPSEC6STAT	47
167 	{ "_ipsec6stat" },
168 #define N_PIM6STAT	48
169 	{ "_pim6stat" },
170 #define N_MRT6PROTO	49
171 	{ "_ip6_mrtproto" },
172 #define N_MRT6STAT	50
173 	{ "_mrt6stat" },
174 #define N_MF6CTABLE	51
175 	{ "_mf6ctable" },
176 #define N_MIF6TABLE	52
177 	{ "_mif6table" },
178 #define N_PFKEYSTAT	53
179 	{ "_pfkeystat" },
180 #define N_ARPSTAT	54
181 	{ "_arpstat" },
182 #define N_RIP6STAT	55
183 	{ "_rip6stat" },
184 	{ "" },
185 };
186 
187 struct protox {
188 	u_char	pr_index;		/* index into nlist of cb head */
189 	u_char	pr_sindex;		/* index into nlist of stat block */
190 	u_char	pr_wanted;		/* 1 if wanted, 0 otherwise */
191 	void	(*pr_cblocks)		/* control blocks printing routine */
192 			__P((u_long, char *));
193 	void	(*pr_stats)		/* statistics printing routine */
194 			__P((u_long, char *));
195 	void	(*pr_istats)
196 			__P((char *));	/* per/if statistics printing routine */
197 	void	(*pr_dump)		/* PCB state dump routine */
198 			__P((u_long));
199 	char	*pr_name;		/* well-known name */
200 } protox[] = {
201 	{ N_TCBTABLE,	N_TCPSTAT,	1,	protopr,
202 	  tcp_stats,	NULL,		tcp_dump,	"tcp" },
203 	{ N_UDBTABLE,	N_UDPSTAT,	1,	protopr,
204 	  udp_stats,	NULL,		0,	"udp" },
205 	{ -1,		N_IPSTAT,	1,	0,
206 	  ip_stats,	NULL,		0,	"ip" },
207 	{ -1,		N_ICMPSTAT,	1,	0,
208 	  icmp_stats,	NULL,		0,	"icmp" },
209 	{ -1,		N_IGMPSTAT,	1,	0,
210 	  igmp_stats,	NULL,		0,	"igmp" },
211 #ifdef IPSEC
212 	{ -1,		N_IPSECSTAT,	1,	0,
213 	  ipsec_stats,	NULL,		0,	"ipsec" },
214 #endif
215 	{ -1,		-1,		0,	0,
216 	  0,		NULL,		0,	0 }
217 };
218 
219 #ifdef INET6
220 struct protox ip6protox[] = {
221 	{ -1,		N_IP6STAT,	1,	0,
222 	  ip6_stats,	ip6_ifstats,	0,	"ip6" },
223 	{ -1,		N_ICMP6STAT,	1,	0,
224 	  icmp6_stats,	icmp6_ifstats,	0,	"icmp6" },
225 #ifdef TCP6
226 	{ N_TCB6,	N_TCP6STAT,	1,	ip6protopr,
227 	  tcp6_stats,	NULL,		tcp6_dump,	"tcp6" },
228 #else
229 	{ N_TCB6,	N_TCP6STAT,	1,	ip6protopr,
230 	  tcp_stats,	NULL,		tcp_dump,	"tcp6" },
231 #endif
232 	{ N_UDB6,	N_UDP6STAT,	1,	ip6protopr,
233 	  udp6_stats,	NULL,		0,	"udp6" },
234 #ifdef IPSEC
235 	{ -1,		N_IPSEC6STAT,	1,	0,
236 	  ipsec_stats,	NULL,		0,	"ipsec6" },
237 #endif
238 	{ -1,		N_PIM6STAT,	1,	0,
239 	  pim6_stats,	NULL,		0,	"pim6" },
240 	{ -1,		N_RIP6STAT,	1,	0,
241 	  rip6_stats,	NULL,		0,	"rip6" },
242 	{ -1,		-1,		0,	0,
243 	  0,		NULL,		0,	0 }
244 };
245 #endif
246 
247 struct protox arpprotox[] = {
248 	{ -1,		N_ARPSTAT,	1,	0,
249 	  arp_stats,	NULL,		0,	"arp" },
250 	{ -1,		-1,		0,	0,
251 	  0,		NULL,		0,	0 }
252 };
253 
254 #ifdef IPSEC
255 struct protox pfkeyprotox[] = {
256 	{ -1,		N_PFKEYSTAT,	1,	0,
257 	  pfkey_stats,	NULL,		0,	"pfkey" },
258 	{ -1,		-1,		0,	0,
259 	  0,		NULL,		0,	0 }
260 };
261 #endif
262 
263 #ifndef SMALL
264 struct protox atalkprotox[] = {
265 	{ N_DDPCB,	N_DDPSTAT,	1,	atalkprotopr,
266 	  ddp_stats,	NULL,		0,	"ddp" },
267 	{ -1,		-1,		0,	0,
268 	  0,		NULL,		0 }
269 };
270 
271 struct protox nsprotox[] = {
272 	{ N_IDP,	N_IDPSTAT,	1,	nsprotopr,
273 	  idp_stats,	NULL,		0,	"idp" },
274 	{ N_IDP,	N_SPPSTAT,	1,	nsprotopr,
275 	  spp_stats,	NULL,		0,	"spp" },
276 	{ -1,		N_NSERR,	1,	0,
277 	  nserr_stats,	NULL,		0,	"ns_err" },
278 	{ -1,		-1,		0,	0,
279 	  0,		NULL,		0 }
280 };
281 
282 struct protox isoprotox[] = {
283 	{ ISO_TP,	N_TPSTAT,	1,	iso_protopr,
284 	  tp_stats,	NULL,		0,	"tp" },
285 	{ N_CLTP,	N_CLTPSTAT,	1,	iso_protopr,
286 	  cltp_stats,	NULL,		0,	"cltp" },
287 	{ -1,		N_CLNPSTAT,	1,	 0,
288 	  clnp_stats,	NULL,		0,	"clnp"},
289 	{ -1,		N_ESISSTAT,	1,	 0,
290 	  esis_stats,	NULL,		0,	"esis"},
291 	{ -1,		-1,		0,	0,
292 	  0,		NULL,		0,	0 }
293 };
294 #endif
295 
296 struct protox *protoprotox[] = { protox,
297 #ifdef INET6
298 				 ip6protox,
299 #endif
300 				 arpprotox,
301 #ifdef IPSEC
302 				 pfkeyprotox,
303 #endif
304 #ifndef SMALL
305 				 atalkprotox, nsprotox, isoprotox,
306 #endif
307 				 NULL };
308 
309 int main __P((int, char *[]));
310 static void printproto __P((struct protox *, char *));
311 static void usage __P((void));
312 static struct protox *name2protox __P((char *));
313 static struct protox *knownname __P((char *));
314 
315 kvm_t *kvmd;
316 
317 int
318 main(argc, argv)
319 	int argc;
320 	char *argv[];
321 {
322 	struct protoent *p;
323 	struct protox *tp;	/* for printing cblocks & stats */
324 	int ch;
325 	char *nlistf = NULL, *memf = NULL;
326 	char buf[_POSIX2_LINE_MAX], *cp;
327 	u_long pcbaddr;
328 	gid_t egid = getegid();
329 
330 	(void)setegid(getgid());
331 	tp = NULL;
332 	af = AF_UNSPEC;
333 	pcbaddr = 0;
334 
335 	while ((ch = getopt(argc, argv, "Aabdf:ghI:LliM:mN:nP:p:rsStuvw:")) != -1)
336 		switch(ch) {
337 		case 'A':
338 			Aflag = 1;
339 			break;
340 		case 'a':
341 			aflag = 1;
342 			break;
343 		case 'b':
344 			bflag = 1;
345 			break;
346 		case 'd':
347 			dflag = 1;
348 			break;
349 		case 'f':
350 			if (strcmp(optarg, "ns") == 0)
351 				af = AF_NS;
352 			else if (strcmp(optarg, "inet") == 0)
353 				af = AF_INET;
354 			else if (strcmp(optarg, "inet6") == 0)
355 				af = AF_INET6;
356 			else if (strcmp(optarg, "arp") == 0)
357 				af = AF_ARP;
358 			else if (strcmp(optarg, "pfkey") == 0)
359 				af = PF_KEY;
360 			else if (strcmp(optarg, "unix") == 0
361 			    || strcmp(optarg, "local") == 0)
362 				af = AF_LOCAL;
363 			else if (strcmp(optarg, "iso") == 0)
364 				af = AF_ISO;
365 			else if (strcmp(optarg, "atalk") == 0)
366 				af = AF_APPLETALK;
367 			else
368 				errx(1, "%s: unknown address family",
369 				    optarg);
370 			break;
371 #ifndef SMALL
372 		case 'g':
373 			gflag = 1;
374 			break;
375 #endif
376 		case 'I':
377 			iflag = 1;
378 			interface = optarg;
379 			break;
380 		case 'i':
381 			iflag = 1;
382 			break;
383 		case 'L':
384 			Lflag = 1;
385 			break;
386 		case 'l':
387 			lflag = 1;
388 			break;
389 		case 'M':
390 			memf = optarg;
391 			break;
392 		case 'm':
393 			mflag = 1;
394 			break;
395 		case 'N':
396 			nlistf = optarg;
397 			break;
398 		case 'n':
399 			numeric_addr = numeric_port = 1;
400 			break;
401 		case 'P':
402 			pcbaddr = strtoul(optarg, &cp, 16);
403 			if (*cp != '\0' || errno == ERANGE)
404 				errx(1, "invalid PCB address %s",
405 				    optarg);
406 			Pflag = 1;
407 			break;
408 		case 'p':
409 			if ((tp = name2protox(optarg)) == NULL)
410 				errx(1, "%s: unknown or uninstrumented protocol",
411 				    optarg);
412 			pflag = 1;
413 			break;
414 		case 'r':
415 			rflag = 1;
416 			break;
417 		case 's':
418 			++sflag;
419 			break;
420 		case 'S':
421 			numeric_addr = 1;
422 			break;
423 		case 't':
424 			tflag = 1;
425 			break;
426 		case 'u':
427 			af = AF_LOCAL;
428 			break;
429 		case 'v':
430 			vflag = 1;
431 			break;
432 		case 'w':
433 			interval = atoi(optarg);
434 			iflag = 1;
435 			break;
436 		case '?':
437 		default:
438 			usage();
439 		}
440 	argv += optind;
441 	argc -= optind;
442 
443 #define	BACKWARD_COMPATIBILITY
444 #ifdef	BACKWARD_COMPATIBILITY
445 	if (*argv) {
446 		if (isdigit(**argv)) {
447 			interval = atoi(*argv);
448 			if (interval <= 0)
449 				usage();
450 			++argv;
451 			iflag = 1;
452 		}
453 		if (*argv) {
454 			nlistf = *argv;
455 			if (*++argv)
456 				memf = *argv;
457 		}
458 	}
459 #endif
460 
461 	/*
462 	 * Discard setgid privileges.  If not the running kernel, we toss
463 	 * them away totally so that bad guys can't print interesting stuff
464 	 * from kernel memory, otherwise switch back to kmem for the
465 	 * duration of the kvm_openfiles() call.
466 	 */
467 	if (nlistf != NULL || memf != NULL || Pflag)
468 		(void)setgid(getgid());
469 	else
470 		(void)setegid(egid);
471 
472 	if ((kvmd = kvm_openfiles(nlistf, memf, NULL, O_RDONLY,
473 	    buf)) == NULL)
474 		errx(1, "%s", buf);
475 
476 	/* do this now anyway */
477 	if (nlistf == NULL && memf == NULL)
478 		(void)setgid(getgid());
479 
480 	if (kvm_nlist(kvmd, nl) < 0 || nl[0].n_type == 0) {
481 		if (nlistf)
482 			errx(1, "%s: no namelist", nlistf);
483 		else
484 			errx(1, "no namelist");
485 	}
486 	if (mflag) {
487 		mbpr(nl[N_MBSTAT].n_value,  nl[N_MSIZE].n_value,
488 		    nl[N_MCLBYTES].n_value, nl[N_MBPOOL].n_value,
489 		    nl[N_MCLPOOL].n_value);
490 		exit(0);
491 	}
492 	if (Pflag) {
493 		if (tp == NULL) {
494 			/* Default to TCP. */
495 			tp = name2protox("tcp");
496 		}
497 		if (tp->pr_dump)
498 			(*tp->pr_dump)(pcbaddr);
499 		else
500 			printf("%s: no PCB dump routine\n", tp->pr_name);
501 		exit(0);
502 	}
503 	if (pflag) {
504 		if (iflag && tp->pr_istats)
505 			intpr(interval, nl[N_IFNET].n_value, tp->pr_istats);
506 		else if (tp->pr_stats)
507 			(*tp->pr_stats)(nl[tp->pr_sindex].n_value,
508 				tp->pr_name);
509 		else
510 			printf("%s: no stats routine\n", tp->pr_name);
511 		exit(0);
512 	}
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 	if (iflag) {
520 		if (af != AF_UNSPEC)
521 			goto protostat;
522 
523 		intpr(interval, nl[N_IFNET].n_value, NULL);
524 		exit(0);
525 	}
526 	if (rflag) {
527 		if (sflag)
528 			rt_stats(nl[N_RTSTAT].n_value);
529 		else
530 			routepr(nl[N_RTREE].n_value);
531 		exit(0);
532 	}
533 #ifndef SMALL
534 	if (gflag) {
535 		if (sflag) {
536 			if (af == AF_INET || af == AF_UNSPEC)
537 				mrt_stats(nl[N_MRTPROTO].n_value,
538 					  nl[N_MRTSTAT].n_value);
539 #ifdef INET6
540 			if (af == AF_INET6 || af == AF_UNSPEC)
541 				mrt6_stats(nl[N_MRT6PROTO].n_value,
542 					   nl[N_MRT6STAT].n_value);
543 #endif
544 		}
545 		else {
546 			if (af == AF_INET || af == AF_UNSPEC)
547 				mroutepr(nl[N_MRTPROTO].n_value,
548 					 nl[N_MFCHASHTBL].n_value,
549 					 nl[N_MFCHASH].n_value,
550 					 nl[N_VIFTABLE].n_value);
551 #ifdef INET6
552 			if (af == AF_INET6 || af == AF_UNSPEC)
553 				mroute6pr(nl[N_MRT6PROTO].n_value,
554 					  nl[N_MF6CTABLE].n_value,
555 					  nl[N_MIF6TABLE].n_value);
556 #endif
557 		}
558 		exit(0);
559 	}
560 #endif
561   protostat:
562 	if (af == AF_INET || af == AF_UNSPEC) {
563 		setprotoent(1);
564 		setservent(1);
565 		/* ugh, this is O(MN) ... why do we do this? */
566 		while ((p = getprotoent()) != NULL) {
567 			for (tp = protox; tp->pr_name; tp++)
568 				if (strcmp(tp->pr_name, p->p_name) == 0)
569 					break;
570 			if (tp->pr_name == 0 || tp->pr_wanted == 0)
571 				continue;
572 			printproto(tp, p->p_name);
573 			tp->pr_wanted = 0;
574 		}
575 		endprotoent();
576 		for (tp = protox; tp->pr_name; tp++)
577 			if (tp->pr_wanted)
578 				printproto(tp, tp->pr_name);
579 	}
580 #ifdef INET6
581 	if (af == AF_INET6 || af == AF_UNSPEC)
582 		for (tp = ip6protox; tp->pr_name; tp++)
583 			printproto(tp, tp->pr_name);
584 #endif
585 	if (af == AF_ARP || af == AF_UNSPEC)
586 		for (tp = arpprotox; tp->pr_name; tp++)
587 			printproto(tp, tp->pr_name);
588 #ifdef IPSEC
589 	if (af == PF_KEY || af == AF_UNSPEC)
590 		for (tp = pfkeyprotox; tp->pr_name; tp++)
591 			printproto(tp, tp->pr_name);
592 #endif
593 #ifndef SMALL
594 	if (af == AF_APPLETALK || af == AF_UNSPEC)
595 		for (tp = atalkprotox; tp->pr_name; tp++)
596 			printproto(tp, tp->pr_name);
597 	if (af == AF_NS || af == AF_UNSPEC)
598 		for (tp = nsprotox; tp->pr_name; tp++)
599 			printproto(tp, tp->pr_name);
600 	if (af == AF_ISO || af == AF_UNSPEC)
601 		for (tp = isoprotox; tp->pr_name; tp++)
602 			printproto(tp, tp->pr_name);
603 	if ((af == AF_LOCAL || af == AF_UNSPEC) && !sflag)
604 		unixpr(nl[N_UNIXSW].n_value);
605 #endif
606 	exit(0);
607 }
608 
609 /*
610  * Print out protocol statistics or control blocks (per sflag).
611  * If the interface was not specifically requested, and the symbol
612  * is not in the namelist, ignore this one.
613  */
614 static void
615 printproto(tp, name)
616 	struct protox *tp;
617 	char *name;
618 {
619 	void (*pr) __P((u_long, char *));
620 	u_long off;
621 
622 	if (sflag) {
623 		if (iflag) {
624 			if (tp->pr_istats)
625 				intpr(interval, nl[N_IFNET].n_value,
626 				      tp->pr_istats);
627 			return;
628 		}
629 		else {
630 			pr = tp->pr_stats;
631 			off = nl[tp->pr_sindex].n_value;
632 		}
633 	} else {
634 		pr = tp->pr_cblocks;
635 		off = nl[tp->pr_index].n_value;
636 	}
637 	if (pr != NULL && (off || af != AF_UNSPEC))
638 		(*pr)(off, name);
639 }
640 
641 /*
642  * Read kernel memory, return 0 on success.
643  */
644 int
645 kread(addr, buf, size)
646 	u_long addr;
647 	char *buf;
648 	int size;
649 {
650 
651 	if (kvm_read(kvmd, addr, buf, size) != size) {
652 		warnx("%s\n", kvm_geterr(kvmd));
653 		return (-1);
654 	}
655 	return (0);
656 }
657 
658 char *
659 plural(n)
660 	int n;
661 {
662 
663 	return (n != 1 ? "s" : "");
664 }
665 
666 char *
667 plurales(n)
668 	int n;
669 {
670 
671 	return (n != 1 ? "es" : "");
672 }
673 
674 /*
675  * Find the protox for the given "well-known" name.
676  */
677 static struct protox *
678 knownname(name)
679 	char *name;
680 {
681 	struct protox **tpp, *tp;
682 
683 	for (tpp = protoprotox; *tpp; tpp++)
684 		for (tp = *tpp; tp->pr_name; tp++)
685 			if (strcmp(tp->pr_name, name) == 0)
686 				return (tp);
687 	return (NULL);
688 }
689 
690 /*
691  * Find the protox corresponding to name.
692  */
693 static struct protox *
694 name2protox(name)
695 	char *name;
696 {
697 	struct protox *tp;
698 	char **alias;			/* alias from p->aliases */
699 	struct protoent *p;
700 
701 	/*
702 	 * Try to find the name in the list of "well-known" names. If that
703 	 * fails, check if name is an alias for an Internet protocol.
704 	 */
705 	if ((tp = knownname(name)) != NULL)
706 		return (tp);
707 
708 	setprotoent(1);			/* make protocol lookup cheaper */
709 	while ((p = getprotoent()) != NULL) {
710 		/* assert: name not same as p->name */
711 		for (alias = p->p_aliases; *alias; alias++)
712 			if (strcmp(name, *alias) == 0) {
713 				endprotoent();
714 				return (knownname(p->p_name));
715 			}
716 	}
717 	endprotoent();
718 	return (NULL);
719 }
720 
721 static void
722 usage()
723 {
724 	const char *progname = getprogname();
725 
726 	(void)fprintf(stderr,
727 "usage: %s [-Aan] [-f address_family] [-M core] [-N system]\n", progname);
728 	(void)fprintf(stderr,
729 "       %s [-gimnrsSv] [-f address_family] [-M core] [-N system]\n",
730 	progname);
731 	(void)fprintf(stderr,
732 "       %s [-n] [-I interface] [-M core] [-N system] [-w wait]\n", progname);
733 	(void)fprintf(stderr,
734 "       %s [-M core] [-N system] [-p protocol]\n", progname);
735 	(void)fprintf(stderr,
736 "       %s [-M core] [-N system] [-p protocol] -P pcbaddr\n", progname);
737 	exit(1);
738 }
739