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main.c revision 1.28
      1 /*	$NetBSD: main.c,v 1.28 2000/07/06 12:40:19 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 1.28 2000/07/06 12:40:19 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 	{ "" },
    181 };
    182 
    183 struct protox {
    184 	u_char	pr_index;		/* index into nlist of cb head */
    185 	u_char	pr_sindex;		/* index into nlist of stat block */
    186 	u_char	pr_wanted;		/* 1 if wanted, 0 otherwise */
    187 	void	(*pr_cblocks)		/* control blocks printing routine */
    188 			__P((u_long, char *));
    189 	void	(*pr_stats)		/* statistics printing routine */
    190 			__P((u_long, char *));
    191 	void	(*pr_istats)
    192 			__P((char *));	/* per/if statistics printing routine */
    193 	void	(*pr_dump)		/* PCB state dump routine */
    194 			__P((u_long));
    195 	char	*pr_name;		/* well-known name */
    196 } protox[] = {
    197 	{ N_TCBTABLE,	N_TCPSTAT,	1,	protopr,
    198 	  tcp_stats,	NULL,		tcp_dump,	"tcp" },
    199 	{ N_UDBTABLE,	N_UDPSTAT,	1,	protopr,
    200 	  udp_stats,	NULL,		0,	"udp" },
    201 	{ -1,		N_IPSTAT,	1,	0,
    202 	  ip_stats,	NULL,		0,	"ip" },
    203 	{ -1,		N_ICMPSTAT,	1,	0,
    204 	  icmp_stats,	NULL,		0,	"icmp" },
    205 	{ -1,		N_IGMPSTAT,	1,	0,
    206 	  igmp_stats,	NULL,		0,	"igmp" },
    207 #ifdef IPSEC
    208 	{ -1,		N_IPSECSTAT,	1,	0,
    209 	  ipsec_stats,	NULL,		0,	"ipsec" },
    210 #endif
    211 	{ -1,		-1,		0,	0,
    212 	  0,		NULL,		0,	0 }
    213 };
    214 
    215 #ifdef INET6
    216 struct protox ip6protox[] = {
    217 	{ -1,		N_IP6STAT,	1,	0,
    218 	  ip6_stats,	ip6_ifstats,	0,	"ip6" },
    219 	{ -1,		N_ICMP6STAT,	1,	0,
    220 	  icmp6_stats,	icmp6_ifstats,	0,	"icmp6" },
    221 #ifdef TCP6
    222 	{ N_TCB6,	N_TCP6STAT,	1,	ip6protopr,
    223 	  tcp6_stats,	NULL,		tcp6_dump,	"tcp6" },
    224 #else
    225 	{ N_TCB6,	N_TCP6STAT,	1,	ip6protopr,
    226 	  tcp_stats,	NULL,		tcp_dump,	"tcp6" },
    227 #endif
    228 	{ N_UDB6,	N_UDP6STAT,	1,	ip6protopr,
    229 	  udp6_stats,	NULL,		0,	"udp6" },
    230 #ifdef IPSEC
    231 	{ -1,		N_IPSEC6STAT,	1,	0,
    232 	  ipsec_stats,	NULL,		0,	"ipsec6" },
    233 #endif
    234 	{ -1,		N_PIM6STAT,	1,	0,
    235 	  pim6_stats,	NULL,		0,	"pim6" },
    236 	{ -1,		-1,		0,	0,
    237 	  0,		NULL,		0,	0 }
    238 };
    239 #endif
    240 
    241 #ifdef IPSEC
    242 struct protox pfkeyprotox[] = {
    243 	{ -1,		N_PFKEYSTAT,	1,	0,
    244 	  pfkey_stats,	NULL,		0,	"pfkey" },
    245 	{ -1,		-1,		0,	0,
    246 	  0,		NULL,		0,	0 }
    247 };
    248 #endif
    249 
    250 #ifndef SMALL
    251 struct protox atalkprotox[] = {
    252 	{ N_DDPCB,	N_DDPSTAT,	1,	atalkprotopr,
    253 	  ddp_stats,	NULL,		0,	"ddp" },
    254 	{ -1,		-1,		0,	0,
    255 	  0,		NULL,		0 }
    256 };
    257 
    258 struct protox nsprotox[] = {
    259 	{ N_IDP,	N_IDPSTAT,	1,	nsprotopr,
    260 	  idp_stats,	NULL,		0,	"idp" },
    261 	{ N_IDP,	N_SPPSTAT,	1,	nsprotopr,
    262 	  spp_stats,	NULL,		0,	"spp" },
    263 	{ -1,		N_NSERR,	1,	0,
    264 	  nserr_stats,	NULL,		0,	"ns_err" },
    265 	{ -1,		-1,		0,	0,
    266 	  0,		NULL,		0 }
    267 };
    268 
    269 struct protox isoprotox[] = {
    270 	{ ISO_TP,	N_TPSTAT,	1,	iso_protopr,
    271 	  tp_stats,	NULL,		0,	"tp" },
    272 	{ N_CLTP,	N_CLTPSTAT,	1,	iso_protopr,
    273 	  cltp_stats,	NULL,		0,	"cltp" },
    274 	{ -1,		N_CLNPSTAT,	1,	 0,
    275 	  clnp_stats,	NULL,		0,	"clnp"},
    276 	{ -1,		N_ESISSTAT,	1,	 0,
    277 	  esis_stats,	NULL,		0,	"esis"},
    278 	{ -1,		-1,		0,	0,
    279 	  0,		NULL,		0,	0 }
    280 };
    281 #endif
    282 
    283 struct protox *protoprotox[] = { protox,
    284 #ifdef INET6
    285 				 ip6protox,
    286 #endif
    287 #ifdef IPSEC
    288 				 pfkeyprotox,
    289 #endif
    290 #ifndef SMALL
    291 				 atalkprotox, nsprotox, isoprotox,
    292 #endif
    293 				 NULL };
    294 
    295 int main __P((int, char *[]));
    296 static void printproto __P((struct protox *, char *));
    297 static void usage __P((void));
    298 static struct protox *name2protox __P((char *));
    299 static struct protox *knownname __P((char *));
    300 
    301 kvm_t *kvmd;
    302 
    303 int
    304 main(argc, argv)
    305 	int argc;
    306 	char *argv[];
    307 {
    308 	struct protoent *p;
    309 	struct protox *tp;	/* for printing cblocks & stats */
    310 	int ch;
    311 	char *nlistf = NULL, *memf = NULL;
    312 	char buf[_POSIX2_LINE_MAX], *cp;
    313 	u_long pcbaddr;
    314 	gid_t egid = getegid();
    315 
    316 	(void)setegid(getgid());
    317 	tp = NULL;
    318 	af = AF_UNSPEC;
    319 	pcbaddr = 0;
    320 
    321 	while ((ch = getopt(argc, argv, "Aabdf:ghI:LliM:mN:nP:p:rstuvw:")) != -1)
    322 		switch(ch) {
    323 		case 'A':
    324 			Aflag = 1;
    325 			break;
    326 		case 'a':
    327 			aflag = 1;
    328 			break;
    329 		case 'b':
    330 			bflag = 1;
    331 			break;
    332 		case 'd':
    333 			dflag = 1;
    334 			break;
    335 		case 'f':
    336 			if (strcmp(optarg, "ns") == 0)
    337 				af = AF_NS;
    338 			else if (strcmp(optarg, "inet") == 0)
    339 				af = AF_INET;
    340 			else if (strcmp(optarg, "inet6") == 0)
    341 				af = AF_INET6;
    342 			else if (strcmp(optarg, "pfkey") == 0)
    343 				af = PF_KEY;
    344 			else if (strcmp(optarg, "unix") == 0
    345 			    || strcmp(optarg, "local") == 0)
    346 				af = AF_LOCAL;
    347 			else if (strcmp(optarg, "iso") == 0)
    348 				af = AF_ISO;
    349 			else if (strcmp(optarg, "atalk") == 0)
    350 				af = AF_APPLETALK;
    351 			else
    352 				errx(1, "%s: unknown address family",
    353 				    optarg);
    354 			break;
    355 #ifndef SMALL
    356 		case 'g':
    357 			gflag = 1;
    358 			break;
    359 #endif
    360 		case 'I':
    361 			iflag = 1;
    362 			interface = optarg;
    363 			break;
    364 		case 'i':
    365 			iflag = 1;
    366 			break;
    367 		case 'L':
    368 			Lflag = 1;
    369 			break;
    370 		case 'l':
    371 			lflag = 1;
    372 			break;
    373 		case 'M':
    374 			memf = optarg;
    375 			break;
    376 		case 'm':
    377 			mflag = 1;
    378 			break;
    379 		case 'N':
    380 			nlistf = optarg;
    381 			break;
    382 		case 'n':
    383 			nflag = 1;
    384 			break;
    385 		case 'P':
    386 			pcbaddr = strtoul(optarg, &cp, 16);
    387 			if (*cp != '\0' || errno == ERANGE)
    388 				errx(1, "invalid PCB address %s",
    389 				    optarg);
    390 			Pflag = 1;
    391 			break;
    392 		case 'p':
    393 			if ((tp = name2protox(optarg)) == NULL)
    394 				errx(1, "%s: unknown or uninstrumented protocol",
    395 				    optarg);
    396 			pflag = 1;
    397 			break;
    398 		case 'r':
    399 			rflag = 1;
    400 			break;
    401 		case 's':
    402 			++sflag;
    403 			break;
    404 		case 't':
    405 			tflag = 1;
    406 			break;
    407 		case 'u':
    408 			af = AF_LOCAL;
    409 			break;
    410 		case 'v':
    411 			vflag = 1;
    412 			break;
    413 		case 'w':
    414 			interval = atoi(optarg);
    415 			iflag = 1;
    416 			break;
    417 		case '?':
    418 		default:
    419 			usage();
    420 		}
    421 	argv += optind;
    422 	argc -= optind;
    423 
    424 #define	BACKWARD_COMPATIBILITY
    425 #ifdef	BACKWARD_COMPATIBILITY
    426 	if (*argv) {
    427 		if (isdigit(**argv)) {
    428 			interval = atoi(*argv);
    429 			if (interval <= 0)
    430 				usage();
    431 			++argv;
    432 			iflag = 1;
    433 		}
    434 		if (*argv) {
    435 			nlistf = *argv;
    436 			if (*++argv)
    437 				memf = *argv;
    438 		}
    439 	}
    440 #endif
    441 
    442 	/*
    443 	 * Discard setgid privileges.  If not the running kernel, we toss
    444 	 * them away totally so that bad guys can't print interesting stuff
    445 	 * from kernel memory, otherwise switch back to kmem for the
    446 	 * duration of the kvm_openfiles() call.
    447 	 */
    448 	if (nlistf != NULL || memf != NULL || Pflag)
    449 		(void)setgid(getgid());
    450 	else
    451 		(void)setegid(egid);
    452 
    453 	if ((kvmd = kvm_openfiles(nlistf, memf, NULL, O_RDONLY,
    454 	    buf)) == NULL)
    455 		errx(1, "%s", buf);
    456 
    457 	/* do this now anyway */
    458 	if (nlistf == NULL && memf == NULL)
    459 		(void)setgid(getgid());
    460 
    461 	if (kvm_nlist(kvmd, nl) < 0 || nl[0].n_type == 0) {
    462 		if (nlistf)
    463 			errx(1, "%s: no namelist", nlistf);
    464 		else
    465 			errx(1, "no namelist");
    466 	}
    467 	if (mflag) {
    468 		mbpr(nl[N_MBSTAT].n_value,  nl[N_MSIZE].n_value,
    469 		    nl[N_MCLBYTES].n_value, nl[N_MBPOOL].n_value,
    470 		    nl[N_MCLPOOL].n_value);
    471 		exit(0);
    472 	}
    473 	if (Pflag) {
    474 		if (tp == NULL) {
    475 			/* Default to TCP. */
    476 			tp = name2protox("tcp");
    477 		}
    478 		if (tp->pr_dump)
    479 			(*tp->pr_dump)(pcbaddr);
    480 		else
    481 			printf("%s: no PCB dump routine\n", tp->pr_name);
    482 		exit(0);
    483 	}
    484 	if (pflag) {
    485 		if (iflag && tp->pr_istats)
    486 			intpr(interval, nl[N_IFNET].n_value, tp->pr_istats);
    487 		else if (tp->pr_stats)
    488 			(*tp->pr_stats)(nl[tp->pr_sindex].n_value,
    489 				tp->pr_name);
    490 		else
    491 			printf("%s: no stats routine\n", tp->pr_name);
    492 		exit(0);
    493 	}
    494 	/*
    495 	 * Keep file descriptors open to avoid overhead
    496 	 * of open/close on each call to get* routines.
    497 	 */
    498 	sethostent(1);
    499 	setnetent(1);
    500 	if (iflag) {
    501 		if (af != AF_UNSPEC)
    502 			goto protostat;
    503 
    504 		intpr(interval, nl[N_IFNET].n_value, NULL);
    505 		exit(0);
    506 	}
    507 	if (rflag) {
    508 		if (sflag)
    509 			rt_stats(nl[N_RTSTAT].n_value);
    510 		else
    511 			routepr(nl[N_RTREE].n_value);
    512 		exit(0);
    513 	}
    514 #ifndef SMALL
    515 	if (gflag) {
    516 		if (sflag) {
    517 			if (af == AF_INET || af == AF_UNSPEC)
    518 				mrt_stats(nl[N_MRTPROTO].n_value,
    519 					  nl[N_MRTSTAT].n_value);
    520 #ifdef INET6
    521 			if (af == AF_INET6 || af == AF_UNSPEC)
    522 				mrt6_stats(nl[N_MRT6PROTO].n_value,
    523 					   nl[N_MRT6STAT].n_value);
    524 #endif
    525 		}
    526 		else {
    527 			if (af == AF_INET || af == AF_UNSPEC)
    528 				mroutepr(nl[N_MRTPROTO].n_value,
    529 					 nl[N_MFCHASHTBL].n_value,
    530 					 nl[N_MFCHASH].n_value,
    531 					 nl[N_VIFTABLE].n_value);
    532 #ifdef INET6
    533 			if (af == AF_INET6 || af == AF_UNSPEC)
    534 				mroute6pr(nl[N_MRT6PROTO].n_value,
    535 					  nl[N_MF6CTABLE].n_value,
    536 					  nl[N_MIF6TABLE].n_value);
    537 #endif
    538 		}
    539 		exit(0);
    540 	}
    541 #endif
    542   protostat:
    543 	if (af == AF_INET || af == AF_UNSPEC) {
    544 		setprotoent(1);
    545 		setservent(1);
    546 		/* ugh, this is O(MN) ... why do we do this? */
    547 		while ((p = getprotoent()) != NULL) {
    548 			for (tp = protox; tp->pr_name; tp++)
    549 				if (strcmp(tp->pr_name, p->p_name) == 0)
    550 					break;
    551 			if (tp->pr_name == 0 || tp->pr_wanted == 0)
    552 				continue;
    553 			printproto(tp, p->p_name);
    554 			tp->pr_wanted = 0;
    555 		}
    556 		endprotoent();
    557 		for (tp = protox; tp->pr_name; tp++)
    558 			if (tp->pr_wanted)
    559 				printproto(tp, tp->pr_name);
    560 	}
    561 #ifdef INET6
    562 	if (af == AF_INET6 || af == AF_UNSPEC)
    563 		for (tp = ip6protox; tp->pr_name; tp++)
    564 			printproto(tp, tp->pr_name);
    565 #endif
    566 #ifdef IPSEC
    567 	if (af == PF_KEY || af == AF_UNSPEC)
    568 		for (tp = pfkeyprotox; tp->pr_name; tp++)
    569 			printproto(tp, tp->pr_name);
    570 #endif
    571 #ifndef SMALL
    572 	if (af == AF_APPLETALK || af == AF_UNSPEC)
    573 		for (tp = atalkprotox; tp->pr_name; tp++)
    574 			printproto(tp, tp->pr_name);
    575 	if (af == AF_NS || af == AF_UNSPEC)
    576 		for (tp = nsprotox; tp->pr_name; tp++)
    577 			printproto(tp, tp->pr_name);
    578 	if (af == AF_ISO || af == AF_UNSPEC)
    579 		for (tp = isoprotox; tp->pr_name; tp++)
    580 			printproto(tp, tp->pr_name);
    581 	if ((af == AF_LOCAL || af == AF_UNSPEC) && !sflag)
    582 		unixpr(nl[N_UNIXSW].n_value);
    583 #endif
    584 	exit(0);
    585 }
    586 
    587 /*
    588  * Print out protocol statistics or control blocks (per sflag).
    589  * If the interface was not specifically requested, and the symbol
    590  * is not in the namelist, ignore this one.
    591  */
    592 static void
    593 printproto(tp, name)
    594 	struct protox *tp;
    595 	char *name;
    596 {
    597 	void (*pr) __P((u_long, char *));
    598 	u_long off;
    599 
    600 	if (sflag) {
    601 		if (iflag) {
    602 			if (tp->pr_istats)
    603 				intpr(interval, nl[N_IFNET].n_value,
    604 				      tp->pr_istats);
    605 			return;
    606 		}
    607 		else {
    608 			pr = tp->pr_stats;
    609 			off = nl[tp->pr_sindex].n_value;
    610 		}
    611 	} else {
    612 		pr = tp->pr_cblocks;
    613 		off = nl[tp->pr_index].n_value;
    614 	}
    615 	if (pr != NULL && (off || af != AF_UNSPEC))
    616 		(*pr)(off, name);
    617 }
    618 
    619 /*
    620  * Read kernel memory, return 0 on success.
    621  */
    622 int
    623 kread(addr, buf, size)
    624 	u_long addr;
    625 	char *buf;
    626 	int size;
    627 {
    628 
    629 	if (kvm_read(kvmd, addr, buf, size) != size) {
    630 		warnx("%s\n", kvm_geterr(kvmd));
    631 		return (-1);
    632 	}
    633 	return (0);
    634 }
    635 
    636 char *
    637 plural(n)
    638 	int n;
    639 {
    640 
    641 	return (n != 1 ? "s" : "");
    642 }
    643 
    644 char *
    645 plurales(n)
    646 	int n;
    647 {
    648 
    649 	return (n != 1 ? "es" : "");
    650 }
    651 
    652 /*
    653  * Find the protox for the given "well-known" name.
    654  */
    655 static struct protox *
    656 knownname(name)
    657 	char *name;
    658 {
    659 	struct protox **tpp, *tp;
    660 
    661 	for (tpp = protoprotox; *tpp; tpp++)
    662 		for (tp = *tpp; tp->pr_name; tp++)
    663 			if (strcmp(tp->pr_name, name) == 0)
    664 				return (tp);
    665 	return (NULL);
    666 }
    667 
    668 /*
    669  * Find the protox corresponding to name.
    670  */
    671 static struct protox *
    672 name2protox(name)
    673 	char *name;
    674 {
    675 	struct protox *tp;
    676 	char **alias;			/* alias from p->aliases */
    677 	struct protoent *p;
    678 
    679 	/*
    680 	 * Try to find the name in the list of "well-known" names. If that
    681 	 * fails, check if name is an alias for an Internet protocol.
    682 	 */
    683 	if ((tp = knownname(name)) != NULL)
    684 		return (tp);
    685 
    686 	setprotoent(1);			/* make protocol lookup cheaper */
    687 	while ((p = getprotoent()) != NULL) {
    688 		/* assert: name not same as p->name */
    689 		for (alias = p->p_aliases; *alias; alias++)
    690 			if (strcmp(name, *alias) == 0) {
    691 				endprotoent();
    692 				return (knownname(p->p_name));
    693 			}
    694 	}
    695 	endprotoent();
    696 	return (NULL);
    697 }
    698 
    699 static void
    700 usage()
    701 {
    702 	(void)fprintf(stderr,
    703 "usage: %s [-Aan] [-f address_family] [-M core] [-N system]\n", __progname);
    704 	(void)fprintf(stderr,
    705 "       %s [-gimnrsv] [-f address_family] [-M core] [-N system]\n",
    706 	__progname);
    707 	(void)fprintf(stderr,
    708 "       %s [-n] [-I interface] [-M core] [-N system] [-w wait]\n", __progname);
    709 	(void)fprintf(stderr,
    710 "       %s [-M core] [-N system] [-p protocol]\n", __progname);
    711 	(void)fprintf(stderr,
    712 "       %s [-M core] [-N system] [-p protocol] -P pcbaddr\n", __progname);
    713 	exit(1);
    714 }
    715