xref: /freebsd/usr.bin/netstat/main.c (revision 2357939bc239bd5334a169b62313806178dd8f30)
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_RTSTAT	1
75 	{ "_rtstat" },
76 #define N_RTREE		2
77 	{ "_rt_tables"},
78 #define N_MRTSTAT	3
79 	{ "_mrtstat" },
80 #define N_MFCTABLE	4
81 	{ "_mfctable" },
82 #define N_VIFTABLE	5
83 	{ "_viftable" },
84 #define N_IPX		6
85 	{ "_ipxpcb"},
86 #define N_IPXSTAT	7
87 	{ "_ipxstat"},
88 #define N_SPXSTAT	8
89 	{ "_spx_istat"},
90 #define N_DDPSTAT	9
91 	{ "_ddpstat"},
92 #define N_DDPCB		10
93 	{ "_ddpcb"},
94 #define N_NGSOCKS	11
95 	{ "_ngsocklist"},
96 #define N_IP6STAT	12
97 	{ "_ip6stat" },
98 #define N_ICMP6STAT	13
99 	{ "_icmp6stat" },
100 #define N_IPSECSTAT	14
101 	{ "_ipsecstat" },
102 #define N_IPSEC6STAT	15
103 	{ "_ipsec6stat" },
104 #define N_PIM6STAT	16
105 	{ "_pim6stat" },
106 #define N_MRT6STAT	17
107 	{ "_mrt6stat" },
108 #define N_MF6CTABLE	18
109 	{ "_mf6ctable" },
110 #define N_MIF6TABLE	19
111 	{ "_mif6table" },
112 #define N_PFKEYSTAT	20
113 	{ "_pfkeystat" },
114 #define N_MBSTAT	21
115 	{ "_mbstat" },
116 #define N_MBTYPES	22
117 	{ "_mbtypes" },
118 #define N_NMBCLUSTERS	23
119 	{ "_nmbclusters" },
120 #define N_NMBUFS	24
121 	{ "_nmbufs" },
122 #define	N_MBHI		25
123 	{ "_mbuf_hiwm" },
124 #define	N_CLHI		26
125 	{ "_clust_hiwm" },
126 #define	N_NCPUS		27
127 	{ "_smp_cpus" },
128 #define	N_PAGESZ	28
129 	{ "_pagesize" },
130 #define	N_MBPSTAT	29
131 	{ "_mb_statpcpu" },
132 #define	N_RTTRASH	30
133 	{ "_rttrash" },
134 #define	N_MBLO		31
135 	{ "_mbuf_lowm" },
136 #define	N_CLLO		32
137 	{ "_clust_lowm" },
138 	{ "" },
139 };
140 
141 struct protox {
142 	u_char	pr_index;		/* index into nlist of cb head */
143 	u_char	pr_sindex;		/* index into nlist of stat block */
144 	u_char	pr_wanted;		/* 1 if wanted, 0 otherwise */
145 	void	(*pr_cblocks)(u_long, const char *, int);
146 					/* control blocks printing routine */
147 	void	(*pr_stats)(u_long, const char *, int);
148 					/* statistics printing routine */
149 	void	(*pr_istats)(char *);	/* per/if statistics printing routine */
150 	const char	*pr_name;		/* well-known name */
151 	u_long	pr_usesysctl;		/* non-zero if we use sysctl, not kvm */
152 } protox[] = {
153 	{ -1,		-1,		1,	protopr,
154 	  tcp_stats,	NULL,		"tcp",	IPPROTO_TCP },
155 	{ -1,		-1,		1,	protopr,
156 	  udp_stats,	NULL,		"udp",	IPPROTO_UDP },
157 	{ -1,		-1,		1,	protopr,
158 	  NULL,		NULL,		"divert",IPPROTO_DIVERT },
159 	{ -1,		-1,		1,	protopr,
160 	  ip_stats,	NULL,		"ip",	IPPROTO_RAW },
161 	{ -1,		-1,		1,	protopr,
162 	  icmp_stats,	NULL,		"icmp",	IPPROTO_ICMP },
163 	{ -1,		-1,		1,	protopr,
164 	  igmp_stats,	NULL,		"igmp",	IPPROTO_IGMP },
165 #ifdef IPSEC
166 	{ -1,		N_IPSECSTAT,	1,	NULL,
167 	  ipsec_stats,	NULL,		"ipsec",	0},
168 #endif
169 	{ -1,		-1,		1,	NULL,
170 	  bdg_stats,	NULL,		"bdg",	1 /* bridging... */ },
171 	{ -1,		-1,		1,	protopr,
172 	  pim_stats,	NULL,		"pim",	IPPROTO_PIM },
173 	{ -1,		-1,		0,	NULL,
174 	  NULL,		NULL,		NULL,	0 }
175 };
176 
177 #ifdef INET6
178 struct protox ip6protox[] = {
179 	{ -1,		-1,		1,	protopr,
180 	  tcp_stats,	NULL,		"tcp",	IPPROTO_TCP },
181 	{ -1,		-1,		1,	protopr,
182 	  udp_stats,	NULL,		"udp",	IPPROTO_UDP },
183 	{ -1,		N_IP6STAT,	1,	protopr,
184 	  ip6_stats,	ip6_ifstats,	"ip6",	IPPROTO_RAW },
185 	{ -1,		N_ICMP6STAT,	1,	protopr,
186 	  icmp6_stats,	icmp6_ifstats,	"icmp6",IPPROTO_ICMPV6 },
187 #ifdef IPSEC
188 	{ -1,		N_IPSEC6STAT,	1,	NULL,
189 	  ipsec_stats,	NULL,		"ipsec6",0 },
190 #endif
191 #ifdef notyet
192 	{ -1,		N_PIM6STAT,	1,	NULL,
193 	  pim6_stats,	NULL,		"pim6",	0 },
194 #endif
195 	{ -1,		-1,		1,	NULL,
196 	  rip6_stats,	NULL,		"rip6",	0 },
197 	{ -1,		-1,		1,	NULL,
198 	  bdg_stats,	NULL,		"bdg",	1 /* bridging... */ },
199 	{ -1,		-1,		0,	NULL,
200 	  NULL,		NULL,		NULL,	0 }
201 };
202 #endif /*INET6*/
203 
204 #ifdef IPSEC
205 struct protox pfkeyprotox[] = {
206 	{ -1,		N_PFKEYSTAT,	1,	NULL,
207 	  pfkey_stats,	NULL,		"pfkey", 0 },
208 	{ -1,		-1,		0,	NULL,
209 	  NULL,		NULL,		NULL,	0 }
210 };
211 #endif
212 
213 struct protox atalkprotox[] = {
214 	{ N_DDPCB,	N_DDPSTAT,	1,	atalkprotopr,
215 	  ddp_stats,	NULL,		"ddp",	0 },
216 	{ -1,		-1,		0,	NULL,
217 	  NULL,		NULL,		NULL,	0 }
218 };
219 
220 struct protox netgraphprotox[] = {
221 	{ N_NGSOCKS,	-1,		1,	netgraphprotopr,
222 	  NULL,		NULL,		"ctrl",	0 },
223 	{ N_NGSOCKS,	-1,		1,	netgraphprotopr,
224 	  NULL,		NULL,		"data",	0 },
225 	{ -1,		-1,		0,	NULL,
226 	  NULL,		NULL,		NULL,	0 }
227 };
228 
229 struct protox ipxprotox[] = {
230 	{ N_IPX,	N_IPXSTAT,	1,	ipxprotopr,
231 	  ipx_stats,	NULL,		"ipx",	0 },
232 	{ N_IPX,	N_SPXSTAT,	1,	ipxprotopr,
233 	  spx_stats,	NULL,		"spx",	0 },
234 	{ -1,		-1,		0,	NULL,
235 	  NULL,		NULL,		0,	0 }
236 };
237 
238 struct protox *protoprotox[] = {
239 					 protox,
240 #ifdef INET6
241 					 ip6protox,
242 #endif
243 #ifdef IPSEC
244 					 pfkeyprotox,
245 #endif
246 					 ipxprotox, atalkprotox, NULL };
247 
248 static void printproto (struct protox *, const char *);
249 static void usage (void);
250 static struct protox *name2protox (char *);
251 static struct protox *knownname (char *);
252 
253 static kvm_t *kvmd;
254 static char *nlistf = NULL, *memf = NULL;
255 
256 int	Aflag;		/* show addresses of protocol control block */
257 int	aflag;		/* show all sockets (including servers) */
258 int	bflag;		/* show i/f total bytes in/out */
259 int	cflag;		/* show mbuf cache information */
260 int	dflag;		/* show i/f dropped packets */
261 int	gflag;		/* show group (multicast) routing or stats */
262 int	iflag;		/* show interfaces */
263 int	Lflag;		/* show size of listen queues */
264 int	mflag;		/* show memory stats */
265 int	numeric_addr;	/* show addresses numerically */
266 int	numeric_port;	/* show ports numerically */
267 static int pflag;	/* show given protocol */
268 int	rflag;		/* show routing tables (or routing stats) */
269 int	sflag;		/* show protocol statistics */
270 int	tflag;		/* show i/f watchdog timers */
271 int	Wflag;		/* wide display */
272 int	zflag;		/* zero stats */
273 
274 int	interval;	/* repeat interval for i/f stats */
275 
276 char	*interface;	/* desired i/f for stats, or NULL for all i/fs */
277 int	unit;		/* unit number for above */
278 
279 int	af;		/* address family */
280 
281 int
282 main(int argc, char *argv[])
283 {
284 	struct protox *tp = NULL;  /* for printing cblocks & stats */
285 	int ch;
286 
287 	af = AF_UNSPEC;
288 
289 	while ((ch = getopt(argc, argv, "Aabcdf:gI:iLlM:mN:np:rSstuWw:z")) != -1)
290 		switch(ch) {
291 		case 'A':
292 			Aflag = 1;
293 			break;
294 		case 'a':
295 			aflag = 1;
296 			break;
297 		case 'b':
298 			bflag = 1;
299 			break;
300 		case 'c':
301 			cflag = 1;
302 			break;
303 		case 'd':
304 			dflag = 1;
305 			break;
306 		case 'f':
307 			if (strcmp(optarg, "ipx") == 0)
308 				af = AF_IPX;
309 			else if (strcmp(optarg, "inet") == 0)
310 				af = AF_INET;
311 #ifdef INET6
312 			else if (strcmp(optarg, "inet6") == 0)
313 				af = AF_INET6;
314 #endif /*INET6*/
315 #ifdef INET6
316 			else if (strcmp(optarg, "pfkey") == 0)
317 				af = PF_KEY;
318 #endif /*INET6*/
319 			else if (strcmp(optarg, "unix") == 0)
320 				af = AF_UNIX;
321 			else if (strcmp(optarg, "atalk") == 0)
322 				af = AF_APPLETALK;
323 			else if (strcmp(optarg, "ng") == 0
324 			    || strcmp(optarg, "netgraph") == 0)
325 				af = AF_NETGRAPH;
326 			else if (strcmp(optarg, "link") == 0)
327 				af = AF_LINK;
328 			else {
329 				errx(1, "%s: unknown address family", optarg);
330 			}
331 			break;
332 		case 'g':
333 			gflag = 1;
334 			break;
335 		case 'I': {
336 			char *cp;
337 
338 			iflag = 1;
339 			for (cp = interface = optarg; isalpha(*cp); cp++)
340 				continue;
341 			unit = atoi(cp);
342 			break;
343 		}
344 		case 'i':
345 			iflag = 1;
346 			break;
347 		case 'L':
348 			Lflag = 1;
349 			break;
350 		case 'M':
351 			memf = optarg;
352 			break;
353 		case 'm':
354 			mflag = 1;
355 			break;
356 		case 'N':
357 			nlistf = optarg;
358 			break;
359 		case 'n':
360 			numeric_addr = numeric_port = 1;
361 			break;
362 		case 'p':
363 			if ((tp = name2protox(optarg)) == NULL) {
364 				errx(1,
365 				     "%s: unknown or uninstrumented protocol",
366 				     optarg);
367 			}
368 			pflag = 1;
369 			break;
370 		case 'r':
371 			rflag = 1;
372 			break;
373 		case 's':
374 			++sflag;
375 			break;
376 		case 'S':
377 			numeric_addr = 1;
378 			break;
379 		case 't':
380 			tflag = 1;
381 			break;
382 		case 'u':
383 			af = AF_UNIX;
384 			break;
385 		case 'W':
386 		case 'l':
387 			Wflag = 1;
388 			break;
389 		case 'w':
390 			interval = atoi(optarg);
391 			iflag = 1;
392 			break;
393 		case 'z':
394 			zflag = 1;
395 			break;
396 		case '?':
397 		default:
398 			usage();
399 		}
400 	argv += optind;
401 	argc -= optind;
402 
403 #define	BACKWARD_COMPATIBILITY
404 #ifdef	BACKWARD_COMPATIBILITY
405 	if (*argv) {
406 		if (isdigit(**argv)) {
407 			interval = atoi(*argv);
408 			if (interval <= 0)
409 				usage();
410 			++argv;
411 			iflag = 1;
412 		}
413 		if (*argv) {
414 			nlistf = *argv;
415 			if (*++argv)
416 				memf = *argv;
417 		}
418 	}
419 #endif
420 
421 	/*
422 	 * Discard setgid privileges if not the running kernel so that bad
423 	 * guys can't print interesting stuff from kernel memory.
424 	 */
425 	if (nlistf != NULL || memf != NULL)
426 		setgid(getgid());
427 
428 	if (cflag && !mflag) {
429 		(void)fprintf(stderr, "-c only valid with -m\n");
430 		usage();
431 	}
432 	if (mflag) {
433 		if (memf != NULL) {
434 			if (kread(0, 0, 0) == 0)
435 				mbpr(nl[N_MBSTAT].n_value,
436 				    nl[N_MBTYPES].n_value,
437 				    nl[N_NMBCLUSTERS].n_value,
438 				    nl[N_NMBUFS].n_value,
439 				    nl[N_MBHI].n_value,
440 				    nl[N_CLHI].n_value,
441 				    nl[N_MBLO].n_value,
442 				    nl[N_CLLO].n_value,
443 				    nl[N_NCPUS].n_value,
444 				    nl[N_PAGESZ].n_value,
445 				    nl[N_MBPSTAT].n_value);
446 		} else
447 			mbpr(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
448 		exit(0);
449 	}
450 #if 0
451 	/*
452 	 * Keep file descriptors open to avoid overhead
453 	 * of open/close on each call to get* routines.
454 	 */
455 	sethostent(1);
456 	setnetent(1);
457 #else
458 	/*
459 	 * This does not make sense any more with DNS being default over
460 	 * the files.  Doing a setXXXXent(1) causes a tcp connection to be
461 	 * used for the queries, which is slower.
462 	 */
463 #endif
464 	if (iflag && !sflag) {
465 		kread(0, 0, 0);
466 		intpr(interval, nl[N_IFNET].n_value, NULL);
467 		exit(0);
468 	}
469 	if (rflag) {
470 		kread(0, 0, 0);
471 		if (sflag)
472 			rt_stats(nl[N_RTSTAT].n_value, nl[N_RTTRASH].n_value);
473 		else
474 			routepr(nl[N_RTREE].n_value);
475 		exit(0);
476 	}
477 	if (gflag) {
478 		kread(0, 0, 0);
479 		if (sflag) {
480 			if (af == AF_INET || af == AF_UNSPEC)
481 				mrt_stats(nl[N_MRTSTAT].n_value);
482 #ifdef INET6
483 			if (af == AF_INET6 || af == AF_UNSPEC)
484 				mrt6_stats(nl[N_MRT6STAT].n_value);
485 #endif
486 		} else {
487 			if (af == AF_INET || af == AF_UNSPEC)
488 				mroutepr(nl[N_MFCTABLE].n_value,
489 					 nl[N_VIFTABLE].n_value);
490 #ifdef INET6
491 			if (af == AF_INET6 || af == AF_UNSPEC)
492 				mroute6pr(nl[N_MF6CTABLE].n_value,
493 					  nl[N_MIF6TABLE].n_value);
494 #endif
495 		}
496 		ifmalist_dump();
497 		exit(0);
498 	}
499 
500 	kread(0, 0, 0);
501 	if (tp) {
502 		printproto(tp, tp->pr_name);
503 		exit(0);
504 	}
505 	if (af == AF_INET || af == AF_UNSPEC)
506 		for (tp = protox; tp->pr_name; tp++)
507 			printproto(tp, tp->pr_name);
508 #ifdef INET6
509 	if (af == AF_INET6 || af == AF_UNSPEC)
510 		for (tp = ip6protox; tp->pr_name; tp++)
511 			printproto(tp, tp->pr_name);
512 #endif /*INET6*/
513 #ifdef IPSEC
514 	if (af == PF_KEY || af == AF_UNSPEC)
515 		for (tp = pfkeyprotox; tp->pr_name; tp++)
516 			printproto(tp, tp->pr_name);
517 #endif /*IPSEC*/
518 	if (af == AF_IPX || af == AF_UNSPEC) {
519 		kread(0, 0, 0);
520 		for (tp = ipxprotox; tp->pr_name; tp++)
521 			printproto(tp, tp->pr_name);
522 	}
523 	if (af == AF_APPLETALK || af == AF_UNSPEC)
524 		for (tp = atalkprotox; tp->pr_name; tp++)
525 			printproto(tp, tp->pr_name);
526 	if (af == AF_NETGRAPH || af == AF_UNSPEC)
527 		for (tp = netgraphprotox; tp->pr_name; tp++)
528 			printproto(tp, tp->pr_name);
529 	if ((af == AF_UNIX || af == AF_UNSPEC) && !Lflag && !sflag)
530 		unixpr();
531 	exit(0);
532 }
533 
534 /*
535  * Print out protocol statistics or control blocks (per sflag).
536  * If the interface was not specifically requested, and the symbol
537  * is not in the namelist, ignore this one.
538  */
539 static void
540 printproto(tp, name)
541 	struct protox *tp;
542 	const char *name;
543 {
544 	void (*pr)(u_long, const char *, int);
545 	u_long off;
546 
547 	if (sflag) {
548 		if (iflag) {
549 			if (tp->pr_istats)
550 				intpr(interval, nl[N_IFNET].n_value,
551 				      tp->pr_istats);
552 			else if (pflag)
553 				printf("%s: no per-interface stats routine\n",
554 				    tp->pr_name);
555 			return;
556 		}
557 		else {
558 			pr = tp->pr_stats;
559 			if (!pr) {
560 				if (pflag)
561 					printf("%s: no stats routine\n",
562 					    tp->pr_name);
563 				return;
564 			}
565 			off = tp->pr_usesysctl ? tp->pr_usesysctl
566 				: nl[tp->pr_sindex].n_value;
567 		}
568 	} else {
569 		pr = tp->pr_cblocks;
570 		if (!pr) {
571 			if (pflag)
572 				printf("%s: no PCB routine\n", tp->pr_name);
573 			return;
574 		}
575 		off = tp->pr_usesysctl ? tp->pr_usesysctl
576 			: nl[tp->pr_index].n_value;
577 	}
578 	if (pr != NULL && (off || af != AF_UNSPEC))
579 		(*pr)(off, name, af);
580 }
581 
582 /*
583  * Read kernel memory, return 0 on success.
584  */
585 int
586 kread(u_long addr, char *buf, int size)
587 {
588 	if (kvmd == 0) {
589 		/*
590 		 * XXX.
591 		 */
592 		kvmd = kvm_openfiles(nlistf, memf, NULL, O_RDONLY, buf);
593 		setgid(getgid());
594 		if (kvmd != NULL) {
595 			if (kvm_nlist(kvmd, nl) < 0) {
596 				if(nlistf)
597 					errx(1, "%s: kvm_nlist: %s", nlistf,
598 					     kvm_geterr(kvmd));
599 				else
600 					errx(1, "kvm_nlist: %s", kvm_geterr(kvmd));
601 			}
602 
603 			if (nl[0].n_type == 0) {
604 				if(nlistf)
605 					errx(1, "%s: no namelist", nlistf);
606 				else
607 					errx(1, "no namelist");
608 			}
609 		} else {
610 			warnx("kvm not available");
611 			return(-1);
612 		}
613 	}
614 	if (!buf)
615 		return (0);
616 	if (kvm_read(kvmd, addr, buf, size) != size) {
617 		warnx("%s", kvm_geterr(kvmd));
618 		return (-1);
619 	}
620 	return (0);
621 }
622 
623 const char *
624 plural(int n)
625 {
626 	return (n != 1 ? "s" : "");
627 }
628 
629 const char *
630 plurales(int n)
631 {
632 	return (n != 1 ? "es" : "");
633 }
634 
635 const char *
636 pluralies(int n)
637 {
638 	return (n != 1 ? "ies" : "y");
639 }
640 
641 /*
642  * Find the protox for the given "well-known" name.
643  */
644 static struct protox *
645 knownname(char *name)
646 {
647 	struct protox **tpp, *tp;
648 
649 	for (tpp = protoprotox; *tpp; tpp++)
650 		for (tp = *tpp; tp->pr_name; tp++)
651 			if (strcmp(tp->pr_name, name) == 0)
652 				return (tp);
653 	return (NULL);
654 }
655 
656 /*
657  * Find the protox corresponding to name.
658  */
659 static struct protox *
660 name2protox(char *name)
661 {
662 	struct protox *tp;
663 	char **alias;			/* alias from p->aliases */
664 	struct protoent *p;
665 
666 	/*
667 	 * Try to find the name in the list of "well-known" names. If that
668 	 * fails, check if name is an alias for an Internet protocol.
669 	 */
670 	if ((tp = knownname(name)) != NULL)
671 		return (tp);
672 
673 	setprotoent(1);			/* make protocol lookup cheaper */
674 	while ((p = getprotoent()) != NULL) {
675 		/* assert: name not same as p->name */
676 		for (alias = p->p_aliases; *alias; alias++)
677 			if (strcmp(name, *alias) == 0) {
678 				endprotoent();
679 				return (knownname(p->p_name));
680 			}
681 	}
682 	endprotoent();
683 	return (NULL);
684 }
685 
686 static void
687 usage(void)
688 {
689 	(void)fprintf(stderr, "%s\n%s\n%s\n%s\n%s\n%s\n%s\n%s\n%s\n%s\n",
690 "usage: netstat [-AaLnSW] [-f protocol_family | -p protocol]\n"
691 "               [-M core] [-N system]",
692 "       netstat -i | -I interface [-abdnt] [-f address_family]\n"
693 "               [-M core] [-N system]",
694 "       netstat -w wait [-I interface] [-d] [-M core] [-N system]",
695 "       netstat -s [-s] [-z] [-f protocol_family | -p protocol] [-M core]",
696 "       netstat -i | -I interface -s [-f protocol_family | -p protocol]\n"
697 "               [-M core] [-N system]",
698 "       netstat -m [-c] [-M core] [-N system]",
699 "       netstat -r [-AenW] [-f address_family] [-M core] [-N system]",
700 "       netstat -rs [-s] [-M core] [-N system]",
701 "       netstat -g [-W] [-f address_family] [-M core] [-N system]",
702 "       netstat -gs [-s] [-f address_family] [-M core] [-N system]");
703 	exit(1);
704 }
705