main.c revision 82664 
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
35char 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
42static char sccsid[] = "@(#)main.c	8.4 (Berkeley) 3/1/94";
43#endif
44static const char rcsid[] =
45  "$FreeBSD: head/usr.bin/netstat/main.c 82664 2001-08-31 16:26:37Z ru $";
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
71static 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
171struct 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, char *, int);
176					/* control blocks printing routine */
177	void	(*pr_stats)(u_long, char *, int);
178					/* statistics printing routine */
179	void	(*pr_istats)(char *);	/* per/if statistics printing routine */
180	char	*pr_name;		/* well-known name */
181	int	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 }
203};
204
205#ifdef INET6
206struct 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
233struct 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
241struct protox atalkprotox[] = {
242	{ N_DDPCB,	N_DDPSTAT,	1,	atalkprotopr,
243	  ddp_stats,	NULL,		"ddp" },
244	{ -1,		-1,		0,	0,
245	  0,		NULL,		0 }
246};
247
248struct protox netgraphprotox[] = {
249	{ N_NGSOCKS,	-1,		1,	netgraphprotopr,
250	  NULL,		NULL,		"ctrl" },
251	{ N_NGSOCKS,	-1,		1,	netgraphprotopr,
252	  NULL,		NULL,		"data" },
253	{ -1,		NULL,		0,	0,
254	  0,		NULL,		0 }
255};
256
257struct 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
267struct 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
280struct 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
294struct 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
311static void printproto (struct protox *, char *);
312static void usage (void);
313static struct protox *name2protox (char *);
314static struct protox *knownname (char *);
315
316static kvm_t *kvmd;
317static char *nlistf = NULL, *memf = NULL;
318
319int	Aflag;		/* show addresses of protocol control block */
320int	aflag;		/* show all sockets (including servers) */
321int	bflag;		/* show i/f total bytes in/out */
322int	dflag;		/* show i/f dropped packets */
323int	gflag;		/* show group (multicast) routing or stats */
324int	iflag;		/* show interfaces */
325int	lflag;		/* show routing table with use and ref */
326int	Lflag;		/* show size of listen queues */
327int	mflag;		/* show memory stats */
328int	numeric_addr;	/* show addresses numerically */
329int	numeric_port;	/* show ports numerically */
330static int pflag;	/* show given protocol */
331int	rflag;		/* show routing tables (or routing stats) */
332int	sflag;		/* show protocol statistics */
333int	tflag;		/* show i/f watchdog timers */
334int	Wflag;		/* wide display */
335int	zflag;		/* zero stats */
336
337int	interval;	/* repeat interval for i/f stats */
338
339char	*interface;	/* desired i/f for stats, or NULL for all i/fs */
340int	unit;		/* unit number for above */
341
342int	af;		/* address family */
343
344int
345main(argc, argv)
346	int argc;
347	char *argv[];
348{
349	register struct protox *tp = NULL;  /* for printing cblocks & stats */
350	int ch;
351
352	af = AF_UNSPEC;
353
354	while ((ch = getopt(argc, argv, "Aabdf:gI:iLlM:mN:np:rSstuWw:z")) != -1)
355		switch(ch) {
356		case 'A':
357			Aflag = 1;
358			break;
359		case 'a':
360			aflag = 1;
361			break;
362		case 'b':
363			bflag = 1;
364			break;
365		case 'd':
366			dflag = 1;
367			break;
368		case 'f':
369#ifdef NS
370			if (strcmp(optarg, "ns") == 0)
371				af = AF_NS;
372			else
373#endif
374			if (strcmp(optarg, "ipx") == 0)
375				af = AF_IPX;
376			else if (strcmp(optarg, "inet") == 0)
377				af = AF_INET;
378#ifdef INET6
379			else if (strcmp(optarg, "inet6") == 0)
380				af = AF_INET6;
381#endif /*INET6*/
382#ifdef INET6
383			else if (strcmp(optarg, "pfkey") == 0)
384				af = PF_KEY;
385#endif /*INET6*/
386			else if (strcmp(optarg, "unix") == 0)
387				af = AF_UNIX;
388			else if (strcmp(optarg, "atalk") == 0)
389				af = AF_APPLETALK;
390			else if (strcmp(optarg, "ng") == 0
391			    || strcmp(optarg, "netgraph") == 0)
392				af = AF_NETGRAPH;
393#ifdef ISO
394			else if (strcmp(optarg, "iso") == 0)
395				af = AF_ISO;
396#endif
397			else {
398				errx(1, "%s: unknown address family", optarg);
399			}
400			break;
401		case 'g':
402			gflag = 1;
403			break;
404		case 'I': {
405			char *cp;
406
407			iflag = 1;
408			for (cp = interface = optarg; isalpha(*cp); cp++)
409				continue;
410			unit = atoi(cp);
411			break;
412		}
413		case 'i':
414			iflag = 1;
415			break;
416		case 'l':
417			lflag = 1;
418			break;
419		case 'L':
420			Lflag = 1;
421			break;
422		case 'M':
423			memf = optarg;
424			break;
425		case 'm':
426			mflag = 1;
427			break;
428		case 'N':
429			nlistf = optarg;
430			break;
431		case 'n':
432			numeric_addr = numeric_port = 1;
433			break;
434		case 'p':
435			if ((tp = name2protox(optarg)) == NULL) {
436				errx(1,
437				     "%s: unknown or uninstrumented protocol",
438				     optarg);
439			}
440			pflag = 1;
441			break;
442		case 'r':
443			rflag = 1;
444			break;
445		case 's':
446			++sflag;
447			break;
448		case 'S':
449			numeric_addr = 1;
450			break;
451		case 't':
452			tflag = 1;
453			break;
454		case 'u':
455			af = AF_UNIX;
456			break;
457		case 'W':
458			Wflag = 1;
459			break;
460		case 'w':
461			interval = atoi(optarg);
462			iflag = 1;
463			break;
464		case 'z':
465			zflag = 1;
466			break;
467		case '?':
468		default:
469			usage();
470		}
471	argv += optind;
472	argc -= optind;
473
474#define	BACKWARD_COMPATIBILITY
475#ifdef	BACKWARD_COMPATIBILITY
476	if (*argv) {
477		if (isdigit(**argv)) {
478			interval = atoi(*argv);
479			if (interval <= 0)
480				usage();
481			++argv;
482			iflag = 1;
483		}
484		if (*argv) {
485			nlistf = *argv;
486			if (*++argv)
487				memf = *argv;
488		}
489	}
490#endif
491
492	/*
493	 * Discard setgid privileges if not the running kernel so that bad
494	 * guys can't print interesting stuff from kernel memory.
495	 */
496	if (nlistf != NULL || memf != NULL)
497		setgid(getgid());
498
499	if (mflag) {
500		if (memf != NULL) {
501			if (kread(0, 0, 0) == 0)
502				mbpr(nl[N_MBSTAT].n_value,
503				    nl[N_MBTYPES].n_value,
504				    nl[N_NMBCLUSTERS].n_value,
505				    nl[N_NMBUFS].n_value,
506				    nl[N_MBLIM].n_value,
507				    nl[N_CLLIM].n_value,
508				    nl[N_NCPUS].n_value,
509				    nl[N_PAGESZ].n_value,
510				    nl[N_MBPSTAT].n_value);
511		} else
512			mbpr(0, 0, 0, 0, 0, 0, 0, 0, 0);
513		exit(0);
514	}
515#if 0
516	/*
517	 * Keep file descriptors open to avoid overhead
518	 * of open/close on each call to get* routines.
519	 */
520	sethostent(1);
521	setnetent(1);
522#else
523	/*
524	 * This does not make sense any more with DNS being default over
525	 * the files.  Doing a setXXXXent(1) causes a tcp connection to be
526	 * used for the queries, which is slower.
527	 */
528#endif
529	if (iflag && !sflag) {
530		kread(0, 0, 0);
531		intpr(interval, nl[N_IFNET].n_value, NULL);
532		exit(0);
533	}
534	if (rflag) {
535		kread(0, 0, 0);
536		if (sflag)
537			rt_stats(nl[N_RTSTAT].n_value, nl[N_RTTRASH].n_value);
538		else
539			routepr(nl[N_RTREE].n_value);
540		exit(0);
541	}
542	if (gflag) {
543		kread(0, 0, 0);
544		if (sflag) {
545			if (af == AF_INET || af == AF_UNSPEC)
546				mrt_stats(nl[N_MRTSTAT].n_value);
547#ifdef INET6
548			if (af == AF_INET6 || af == AF_UNSPEC)
549				mrt6_stats(nl[N_MRT6STAT].n_value);
550#endif
551		} else {
552			if (af == AF_INET || af == AF_UNSPEC)
553				mroutepr(nl[N_MFCTABLE].n_value,
554					 nl[N_VIFTABLE].n_value);
555#ifdef INET6
556			if (af == AF_INET6 || af == AF_UNSPEC)
557				mroute6pr(nl[N_MF6CTABLE].n_value,
558					  nl[N_MIF6TABLE].n_value);
559#endif
560		}
561		exit(0);
562	}
563
564	kread(0, 0, 0);
565	if (tp) {
566		printproto(tp, tp->pr_name);
567		exit(0);
568	}
569	if (af == AF_INET || af == AF_UNSPEC)
570		for (tp = protox; tp->pr_name; tp++)
571			printproto(tp, tp->pr_name);
572#ifdef INET6
573	if (af == AF_INET6 || af == AF_UNSPEC)
574		for (tp = ip6protox; tp->pr_name; tp++)
575			printproto(tp, tp->pr_name);
576#endif /*INET6*/
577#ifdef IPSEC
578	if (af == PF_KEY || af == AF_UNSPEC)
579		for (tp = pfkeyprotox; tp->pr_name; tp++)
580			printproto(tp, tp->pr_name);
581#endif /*IPSEC*/
582	if (af == AF_IPX || af == AF_UNSPEC) {
583		kread(0, 0, 0);
584		for (tp = ipxprotox; tp->pr_name; tp++)
585			printproto(tp, tp->pr_name);
586	}
587	if (af == AF_APPLETALK || af == AF_UNSPEC)
588		for (tp = atalkprotox; tp->pr_name; tp++)
589			printproto(tp, tp->pr_name);
590	if (af == AF_NETGRAPH || af == AF_UNSPEC)
591		for (tp = netgraphprotox; tp->pr_name; tp++)
592			printproto(tp, tp->pr_name);
593#ifdef NS
594	if (af == AF_NS || af == AF_UNSPEC)
595		for (tp = nsprotox; tp->pr_name; tp++)
596			printproto(tp, tp->pr_name);
597#endif
598#ifdef ISO
599	if (af == AF_ISO || af == AF_UNSPEC)
600		for (tp = isoprotox; tp->pr_name; tp++)
601			printproto(tp, tp->pr_name);
602#endif
603	if ((af == AF_UNIX || af == AF_UNSPEC) && !Lflag && !sflag)
604		unixpr();
605	exit(0);
606}
607
608/*
609 * Print out protocol statistics or control blocks (per sflag).
610 * If the interface was not specifically requested, and the symbol
611 * is not in the namelist, ignore this one.
612 */
613static void
614printproto(tp, name)
615	register struct protox *tp;
616	char *name;
617{
618	void (*pr)(u_long, char *, int);
619	u_long off;
620
621	if (sflag) {
622		if (iflag) {
623			if (tp->pr_istats)
624				intpr(interval, nl[N_IFNET].n_value,
625				      tp->pr_istats);
626			else if (pflag)
627				printf("%s: no per-interface stats routine\n",
628				    tp->pr_name);
629			return;
630		}
631		else {
632			pr = tp->pr_stats;
633			if (!pr) {
634				if (pflag)
635					printf("%s: no stats routine\n",
636					    tp->pr_name);
637				return;
638			}
639			off = tp->pr_usesysctl ? tp->pr_usesysctl
640				: nl[tp->pr_sindex].n_value;
641		}
642	} else {
643		pr = tp->pr_cblocks;
644		if (!pr) {
645			if (pflag)
646				printf("%s: no PCB routine\n", tp->pr_name);
647			return;
648		}
649		off = tp->pr_usesysctl ? tp->pr_usesysctl
650			: nl[tp->pr_index].n_value;
651	}
652	if (pr != NULL && (off || af != AF_UNSPEC))
653		(*pr)(off, name, af);
654}
655
656/*
657 * Read kernel memory, return 0 on success.
658 */
659int
660kread(u_long addr, char *buf, int size)
661{
662	if (kvmd == 0) {
663		/*
664		 * XXX.
665		 */
666		kvmd = kvm_openfiles(nlistf, memf, NULL, O_RDONLY, buf);
667		setgid(getgid());
668		if (kvmd != NULL) {
669			if (kvm_nlist(kvmd, nl) < 0) {
670				if(nlistf)
671					errx(1, "%s: kvm_nlist: %s", nlistf,
672					     kvm_geterr(kvmd));
673				else
674					errx(1, "kvm_nlist: %s", kvm_geterr(kvmd));
675			}
676
677			if (nl[0].n_type == 0) {
678				if(nlistf)
679					errx(1, "%s: no namelist", nlistf);
680				else
681					errx(1, "no namelist");
682			}
683		} else {
684			warnx("kvm not available");
685			return(-1);
686		}
687	}
688	if (!buf)
689		return (0);
690	if (kvm_read(kvmd, addr, buf, size) != size) {
691		warnx("%s", kvm_geterr(kvmd));
692		return (-1);
693	}
694	return (0);
695}
696
697char *
698plural(int n)
699{
700	return (n != 1 ? "s" : "");
701}
702
703char *
704plurales(int n)
705{
706	return (n != 1 ? "es" : "");
707}
708
709/*
710 * Find the protox for the given "well-known" name.
711 */
712static struct protox *
713knownname(char *name)
714{
715	struct protox **tpp, *tp;
716
717	for (tpp = protoprotox; *tpp; tpp++)
718		for (tp = *tpp; tp->pr_name; tp++)
719			if (strcmp(tp->pr_name, name) == 0)
720				return (tp);
721	return (NULL);
722}
723
724/*
725 * Find the protox corresponding to name.
726 */
727static struct protox *
728name2protox(char *name)
729{
730	struct protox *tp;
731	char **alias;			/* alias from p->aliases */
732	struct protoent *p;
733
734	/*
735	 * Try to find the name in the list of "well-known" names. If that
736	 * fails, check if name is an alias for an Internet protocol.
737	 */
738	if ((tp = knownname(name)) != NULL)
739		return (tp);
740
741	setprotoent(1);			/* make protocol lookup cheaper */
742	while ((p = getprotoent()) != NULL) {
743		/* assert: name not same as p->name */
744		for (alias = p->p_aliases; *alias; alias++)
745			if (strcmp(name, *alias) == 0) {
746				endprotoent();
747				return (knownname(p->p_name));
748			}
749	}
750	endprotoent();
751	return (NULL);
752}
753
754static void
755usage(void)
756{
757	(void)fprintf(stderr, "%s\n%s\n%s\n%s\n%s\n",
758"usage: netstat [-AaLlnW] [-f address_family] [-M core] [-N system]",
759"       netstat [-abdgilnrsS] [-f address_family] [-M core] [-N system]",
760"       netstat [-bdn] [-I interface] [-M core] [-N system] [-w wait]",
761"       netstat -m [-M core] [-N system]",
762"       netstat [-M core] [-N system] [-p protocol]");
763	exit(1);
764}
765