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mrinfo.c revision 1.7.10.2
      1 /*	$NetBSD: mrinfo.c,v 1.7.10.2 2002/09/04 00:53:00 itojun Exp $	*/
      2 
      3 /*
      4  * This tool requests configuration info from a multicast router
      5  * and prints the reply (if any).  Invoke it as:
      6  *
      7  *	mrinfo router-name-or-address
      8  *
      9  * Written Wed Mar 24 1993 by Van Jacobson (adapted from the
     10  * multicast mapper written by Pavel Curtis).
     11  *
     12  * The lawyers insist we include the following UC copyright notice.
     13  * The mapper from which this is derived contained a Xerox copyright
     14  * notice which follows the UC one.  Try not to get depressed noting
     15  * that the legal gibberish is larger than the program.
     16  *
     17  * Copyright (c) 1993 Regents of the University of California.
     18  * All rights reserved.
     19  *
     20  * Redistribution and use in source and binary forms, with or without
     21  * modification, are permitted provided that the following conditions
     22  * are met:
     23  * 1. Redistributions of source code must retain the above copyright
     24  *    notice, this list of conditions and the following disclaimer.
     25  * 2. Redistributions in binary form must reproduce the above copyright
     26  *    notice, this list of conditions and the following disclaimer in the
     27  *    documentation and/or other materials provided with the distribution.
     28  * 3. All advertising materials mentioning features or use of this software
     29  *    must display the following acknowledgement:
     30  *	This product includes software developed by the Computer Systems
     31  *	Engineering Group at Lawrence Berkeley Laboratory.
     32  * 4. Neither the name of the University nor of the Laboratory may be used
     33  *    to endorse or promote products derived from this software without
     34  *    specific prior written permission.
     35  *
     36  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     37  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     38  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     39  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     40  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     41  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     42  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     43  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     44  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     45  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     46  * SUCH DAMAGE.
     47  * ---------------------------------
     48  * Copyright (c) Xerox Corporation 1992. All rights reserved.
     49  *
     50  * License is granted to copy, to use, and to make and to use derivative works
     51  * for research and evaluation purposes, provided that Xerox is acknowledged
     52  * in all documentation pertaining to any such copy or derivative work. Xerox
     53  * grants no other licenses expressed or implied. The Xerox trade name should
     54  * not be used in any advertising without its written permission.
     55  *
     56  * XEROX CORPORATION MAKES NO REPRESENTATIONS CONCERNING EITHER THE
     57  * MERCHANTABILITY OF THIS SOFTWARE OR THE SUITABILITY OF THIS SOFTWARE FOR
     58  * ANY PARTICULAR PURPOSE.  The software is provided "as is" without express
     59  * or implied warranty of any kind.
     60  *
     61  * These notices must be retained in any copies of any part of this software.
     62  */
     63 
     64 #include <sys/cdefs.h>
     65 #ifndef lint
     66 #if 0
     67 static char rcsid[] =
     68     "@(#) Header: mrinfo.c,v 1.6 93/04/08 15:14:16 van Exp (LBL)";
     69 #else
     70 __RCSID("$NetBSD: mrinfo.c,v 1.7.10.2 2002/09/04 00:53:00 itojun Exp $");
     71 #endif
     72 #endif
     73 
     74 #include <string.h>
     75 #include <netdb.h>
     76 #include <sys/time.h>
     77 #include "defs.h"
     78 #include <arpa/inet.h>
     79 #ifdef __STDC__
     80 #include <stdarg.h>
     81 #else
     82 #include <varargs.h>
     83 #endif
     84 
     85 #define DEFAULT_TIMEOUT	4	/* How long to wait before retrying requests */
     86 #define DEFAULT_RETRIES 3	/* How many times to ask each router */
     87 
     88 u_int32_t	our_addr, target_addr = 0;	/* in NET order */
     89 int     debug = 0;
     90 int	nflag = 0;
     91 int     retries = DEFAULT_RETRIES;
     92 int     timeout = DEFAULT_TIMEOUT;
     93 int	target_level = 0;
     94 vifi_t  numvifs;		/* to keep loader happy */
     95 				/* (see COPY_TABLES macro called in kern.c) */
     96 
     97 char *			inet_name __P((u_int32_t addr));
     98 void			ask __P((u_int32_t dst));
     99 void			ask2 __P((u_int32_t dst));
    100 int			get_number __P((int *var, int deflt, char ***pargv,
    101 					int *pargc));
    102 u_int32_t			host_addr __P((char *name));
    103 void			usage __P((void));
    104 
    105 /* to shut up -Wstrict-prototypes */
    106 int			main __P((int argc, char *argv[]));
    107 
    108 
    109 char   *
    110 inet_name(addr)
    111 	u_int32_t  addr;
    112 {
    113 	struct hostent *e;
    114 	struct in_addr in;
    115 
    116 	if (addr == 0)
    117 		return "local";
    118 
    119 	if (nflag ||
    120 	    (e = gethostbyaddr((char *)&addr, sizeof(addr), AF_INET)) == NULL) {
    121 		in.s_addr = addr;
    122 		return (inet_ntoa(in));
    123 	}
    124 	return (e->h_name);
    125 }
    126 
    127 /*
    128  * Log errors and other messages to stderr, according to the severity of the
    129  * message and the current debug level.  For errors of severity LOG_ERR or
    130  * worse, terminate the program.
    131  */
    132 #ifdef __STDC__
    133 void
    134 log(int severity, int syserr, const char *format, ...)
    135 {
    136 	va_list ap;
    137 
    138 	va_start(ap, format);
    139 #else
    140 void
    141 log(severity, syserr, format, va_alist)
    142 	int     severity, syserr;
    143 	char   *format;
    144 	va_dcl
    145 {
    146 	va_list ap;
    147 
    148 	va_start(ap);
    149 #endif
    150 	switch (debug) {
    151 	case 0:
    152 		if (severity > LOG_WARNING)
    153 			return;
    154 	case 1:
    155 		if (severity > LOG_NOTICE)
    156 			return;
    157 	case 2:
    158 		if (severity > LOG_INFO)
    159 			return;
    160 	default:
    161 		if (severity == LOG_WARNING)
    162 			fprintf(stderr, "warning - ");
    163 		vfprintf(stderr, format, ap);
    164 		if (syserr == 0)
    165 			fprintf(stderr, "\n");
    166 		else
    167 			fprintf(stderr, ": %s\n", strerror(syserr));
    168 	}
    169 
    170 	if (severity <= LOG_ERR)
    171 		exit(-1);
    172 }
    173 
    174 /*
    175  * Send a neighbors-list request.
    176  */
    177 void
    178 ask(dst)
    179 	u_int32_t  dst;
    180 {
    181 	send_igmp(our_addr, dst, IGMP_DVMRP, DVMRP_ASK_NEIGHBORS,
    182 			htonl(MROUTED_LEVEL), 0);
    183 }
    184 
    185 void
    186 ask2(dst)
    187 	u_int32_t  dst;
    188 {
    189 	send_igmp(our_addr, dst, IGMP_DVMRP, DVMRP_ASK_NEIGHBORS2,
    190 			htonl(MROUTED_LEVEL), 0);
    191 }
    192 
    193 /*
    194  * Process an incoming neighbor-list message.
    195  */
    196 void
    197 accept_neighbors(src, dst, p, datalen, level)
    198 	u_int32_t	src, dst, level;
    199 	u_char	*p;
    200 	int     datalen;
    201 {
    202 	u_char *ep = p + datalen;
    203 #define GET_ADDR(a) (a = ((u_int32_t)*p++ << 24), a += ((u_int32_t)*p++ << 16),\
    204 		     a += ((u_int32_t)*p++ << 8), a += *p++)
    205 
    206 	printf("%s (%s):\n", inet_fmt(src, s1), inet_name(src));
    207 	while (p < ep) {
    208 		register u_int32_t laddr;
    209 		register u_char metric;
    210 		register u_char thresh;
    211 		register int ncount;
    212 
    213 		GET_ADDR(laddr);
    214 		laddr = htonl(laddr);
    215 		metric = *p++;
    216 		thresh = *p++;
    217 		ncount = *p++;
    218 		while (--ncount >= 0) {
    219 			register u_int32_t neighbor;
    220 			GET_ADDR(neighbor);
    221 			neighbor = htonl(neighbor);
    222 			printf("  %s -> ", inet_fmt(laddr, s1));
    223 			printf("%s (%s) [%d/%d]\n", inet_fmt(neighbor, s1),
    224 			       inet_name(neighbor), metric, thresh);
    225 		}
    226 	}
    227 }
    228 
    229 void
    230 accept_neighbors2(src, dst, p, datalen, level)
    231 	u_int32_t	src, dst, level;
    232 	u_char	*p;
    233 	int     datalen;
    234 {
    235 	u_char *ep = p + datalen;
    236 	u_int broken_cisco = ((level & 0xffff) == 0x020a); /* 10.2 */
    237 	/* well, only possibly_broken_cisco, but that's too long to type. */
    238 
    239 	printf("%s (%s) [version %d.%d", inet_fmt(src, s1), inet_name(src),
    240 	       level & 0xff, (level >> 8) & 0xff);
    241 	if ((level >> 16) & NF_LEAF)   { printf (",leaf"); }
    242 	if ((level >> 16) & NF_PRUNE)  { printf (",prune"); }
    243 	if ((level >> 16) & NF_GENID)  { printf (",genid"); }
    244 	if ((level >> 16) & NF_MTRACE) { printf (",mtrace"); }
    245 	printf ("]:\n");
    246 
    247 	while (p < ep) {
    248 		register u_char metric;
    249 		register u_char thresh;
    250 		register u_char flags;
    251 		register int ncount;
    252 		register u_int32_t laddr = *(u_int32_t*)p;
    253 
    254 		p += 4;
    255 		metric = *p++;
    256 		thresh = *p++;
    257 		flags = *p++;
    258 		ncount = *p++;
    259 		if (broken_cisco && ncount == 0)	/* dumb Ciscos */
    260 			ncount = 1;
    261 		if (broken_cisco && ncount > 15)	/* dumb Ciscos */
    262 			ncount = ncount & 0xf;
    263 		while (--ncount >= 0 && p < ep) {
    264 			register u_int32_t neighbor = *(u_int32_t*)p;
    265 			p += 4;
    266 			printf("  %s -> ", inet_fmt(laddr, s1));
    267 			printf("%s (%s) [%d/%d", inet_fmt(neighbor, s1),
    268 			       inet_name(neighbor), metric, thresh);
    269 			if (flags & DVMRP_NF_TUNNEL)
    270 				printf("/tunnel");
    271 			if (flags & DVMRP_NF_SRCRT)
    272 				printf("/srcrt");
    273 			if (flags & DVMRP_NF_PIM)
    274 				printf("/pim");
    275 			if (flags & DVMRP_NF_QUERIER)
    276 				printf("/querier");
    277 			if (flags & DVMRP_NF_DISABLED)
    278 				printf("/disabled");
    279 			if (flags & DVMRP_NF_DOWN)
    280 				printf("/down");
    281 			if (flags & DVMRP_NF_LEAF)
    282 				printf("/leaf");
    283 			printf("]\n");
    284 		}
    285 	}
    286 }
    287 
    288 int
    289 get_number(var, deflt, pargv, pargc)
    290 	int    *var, *pargc, deflt;
    291 	char ***pargv;
    292 {
    293 	if ((*pargv)[0][2] == '\0') {	/* Get the value from the next
    294 					 * argument */
    295 		if (*pargc > 1 && isdigit((*pargv)[1][0])) {
    296 			(*pargv)++, (*pargc)--;
    297 			*var = atoi((*pargv)[0]);
    298 			return 1;
    299 		} else if (deflt >= 0) {
    300 			*var = deflt;
    301 			return 1;
    302 		} else
    303 			return 0;
    304 	} else {		/* Get value from the rest of this argument */
    305 		if (isdigit((*pargv)[0][2])) {
    306 			*var = atoi((*pargv)[0] + 2);
    307 			return 1;
    308 		} else {
    309 			return 0;
    310 		}
    311 	}
    312 }
    313 
    314 void
    315 usage()
    316 {
    317 	fprintf(stderr,
    318 	    "Usage: mrinfo [-n] [-t timeout] [-r retries] [router]\n");
    319 	exit(1);
    320 }
    321 
    322 int
    323 main(argc, argv)
    324 	int     argc;
    325 	char   *argv[];
    326 {
    327 	int tries;
    328 	int trynew;
    329 	struct timeval et;
    330 	struct hostent *hp;
    331 	struct hostent bogus;
    332 	char *host;
    333 	int curaddr;
    334 
    335 	if (geteuid() != 0) {
    336 		fprintf(stderr, "mrinfo: must be root\n");
    337 		exit(1);
    338 	}
    339 	init_igmp();
    340 	if (setuid(getuid()) == -1)
    341 		log(LOG_ERR, errno, "setuid");
    342 
    343 	setlinebuf(stderr);
    344 
    345 	argv++, argc--;
    346 	while (argc > 0 && argv[0][0] == '-') {
    347 		switch (argv[0][1]) {
    348 		case 'd':
    349 			if (!get_number(&debug, DEFAULT_DEBUG, &argv, &argc))
    350 				usage();
    351 			break;
    352 		case 'n':
    353 			++nflag;
    354 			break;
    355 		case 'r':
    356 			if (!get_number(&retries, -1, &argv, &argc))
    357 				usage();
    358 			break;
    359 		case 't':
    360 			if (!get_number(&timeout, -1, &argv, &argc))
    361 				usage();
    362 			break;
    363 		default:
    364 			usage();
    365 		}
    366 		argv++, argc--;
    367 	}
    368 	if (argc > 1)
    369 		usage();
    370 	if (argc == 1)
    371 		host = argv[0];
    372 	else
    373 		host = "127.0.0.1";
    374 
    375 	if ((target_addr = inet_addr(host)) != -1) {
    376 		hp = &bogus;
    377 		hp->h_length = sizeof(target_addr);
    378 		hp->h_addr_list = (char **)malloc(2 * sizeof(char *));
    379 		if (hp->h_addr_list == NULL)
    380 			log(LOG_ERR, errno, "malloc");
    381 		hp->h_addr_list[0] = malloc(hp->h_length);
    382 		if (hp->h_addr_list[0] == NULL)
    383 			log(LOG_ERR, errno, "malloc");
    384 		memcpy(hp->h_addr_list[0], &target_addr, sizeof(hp->h_addr_list[0]));
    385 		hp->h_addr_list[1] = NULL;
    386 	} else
    387 		hp = gethostbyname(host);
    388 
    389 	if (hp == NULL || hp->h_length != sizeof(target_addr)) {
    390 		fprintf(stderr, "mrinfo: %s: no such host\n", argv[0]);
    391 		exit(1);
    392 	}
    393 	if (debug)
    394 		fprintf(stderr, "Debug level %u\n", debug);
    395 
    396 	/* Check all addresses; mrouters often have unreachable interfaces */
    397 	for (curaddr = 0; hp->h_addr_list[curaddr] != NULL; curaddr++) {
    398 	    memcpy(&target_addr, hp->h_addr_list[curaddr], sizeof(target_addr));
    399 	    {			/* Find a good local address for us. */
    400 		int     udp;
    401 		struct sockaddr_in addr;
    402 		int     addrlen = sizeof(addr);
    403 
    404 		addr.sin_family = AF_INET;
    405 #if (defined(BSD) && (BSD >= 199103))
    406 		addr.sin_len = sizeof addr;
    407 #endif
    408 		addr.sin_addr.s_addr = target_addr;
    409 		addr.sin_port = htons(2000);	/* any port over 1024 will
    410 						 * do... */
    411 		if ((udp = socket(AF_INET, SOCK_DGRAM, 0)) < 0
    412 		|| connect(udp, (struct sockaddr *) & addr, sizeof(addr)) < 0
    413 		    || getsockname(udp, (struct sockaddr *) & addr, &addrlen) < 0) {
    414 			perror("Determining local address");
    415 			exit(-1);
    416 		}
    417 		close(udp);
    418 		our_addr = addr.sin_addr.s_addr;
    419 	    }
    420 
    421 	    tries = 0;
    422 	    trynew = 1;
    423 	    /*
    424 	     * New strategy: send 'ask2' for two timeouts, then fall back
    425 	     * to 'ask', since it's not very likely that we are going to
    426 	     * find someone who only responds to 'ask' these days
    427 	     */
    428 	    ask2(target_addr);
    429 
    430 	    gettimeofday(&et, 0);
    431 	    et.tv_sec += timeout;
    432 
    433 	    /* Main receive loop */
    434 	    for (;;) {
    435 		fd_set  fds;
    436 		struct timeval tv, now;
    437 		int     count, recvlen, dummy = 0;
    438 		register u_int32_t src, dst, group;
    439 		struct ip *ip;
    440 		struct igmp *igmp;
    441 		int     ipdatalen, iphdrlen, igmpdatalen;
    442 
    443 		FD_ZERO(&fds);
    444 		if (igmp_socket >= FD_SETSIZE)
    445 			log(LOG_ERR, 0, "descriptor too big");
    446 		FD_SET(igmp_socket, &fds);
    447 
    448 		gettimeofday(&now, 0);
    449 		tv.tv_sec = et.tv_sec - now.tv_sec;
    450 		tv.tv_usec = et.tv_usec - now.tv_usec;
    451 
    452 		if (tv.tv_usec < 0) {
    453 			tv.tv_usec += 1000000L;
    454 			--tv.tv_sec;
    455 		}
    456 		if (tv.tv_sec < 0)
    457 			tv.tv_sec = tv.tv_usec = 0;
    458 
    459 		count = select(igmp_socket + 1, &fds, 0, 0, &tv);
    460 
    461 		if (count < 0) {
    462 			if (errno != EINTR)
    463 				perror("select");
    464 			continue;
    465 		} else if (count == 0) {
    466 			log(LOG_DEBUG, 0, "Timed out receiving neighbor lists");
    467 			if (++tries > retries)
    468 				break;
    469 			/* If we've tried ASK_NEIGHBORS2 twice with
    470 			 * no response, fall back to ASK_NEIGHBORS
    471 			 */
    472 			if (tries == 2 && target_level == 0)
    473 				trynew = 0;
    474 			if (target_level == 0 && trynew == 0)
    475 				ask(target_addr);
    476 			else
    477 				ask2(target_addr);
    478 			gettimeofday(&et, 0);
    479 			et.tv_sec += timeout;
    480 			continue;
    481 		}
    482 		recvlen = recvfrom(igmp_socket, recv_buf, RECV_BUF_SIZE,
    483 				   0, NULL, &dummy);
    484 		if (recvlen <= 0) {
    485 			if (recvlen && errno != EINTR)
    486 				perror("recvfrom");
    487 			continue;
    488 		}
    489 
    490 		if (recvlen < sizeof(struct ip)) {
    491 			log(LOG_WARNING, 0,
    492 			    "packet too short (%u bytes) for IP header",
    493 			    recvlen);
    494 			continue;
    495 		}
    496 		ip = (struct ip *) recv_buf;
    497 		if (ip->ip_p == 0)
    498 			continue;	/* Request to install cache entry */
    499 		src = ip->ip_src.s_addr;
    500 		dst = ip->ip_dst.s_addr;
    501 		iphdrlen = ip->ip_hl << 2;
    502 		ipdatalen = ip->ip_len;
    503 		if (iphdrlen + ipdatalen != recvlen) {
    504 		    log(LOG_WARNING, 0,
    505 		      "packet shorter (%u bytes) than hdr+data length (%u+%u)",
    506 		      recvlen, iphdrlen, ipdatalen);
    507 		    continue;
    508 		}
    509 		igmp = (struct igmp *) (recv_buf + iphdrlen);
    510 		group = igmp->igmp_group.s_addr;
    511 		igmpdatalen = ipdatalen - IGMP_MINLEN;
    512 		if (igmpdatalen < 0) {
    513 		    log(LOG_WARNING, 0,
    514 			"IP data field too short (%u bytes) for IGMP, from %s",
    515 			ipdatalen, inet_fmt(src, s1));
    516 		    continue;
    517 		}
    518 		if (igmp->igmp_type != IGMP_DVMRP)
    519 			continue;
    520 
    521 		switch (igmp->igmp_code) {
    522 		case DVMRP_NEIGHBORS:
    523 		case DVMRP_NEIGHBORS2:
    524 			if (src != target_addr) {
    525 				fprintf(stderr, "mrinfo: got reply from %s",
    526 					inet_fmt(src, s1));
    527 				fprintf(stderr, " instead of %s\n",
    528 					inet_fmt(target_addr, s1));
    529 				/*continue;*/
    530 			}
    531 			break;
    532 		default:
    533 			continue;	/* ignore all other DVMRP messages */
    534 		}
    535 
    536 		switch (igmp->igmp_code) {
    537 
    538 		case DVMRP_NEIGHBORS:
    539 			if (group) {
    540 				/* knows about DVMRP_NEIGHBORS2 msg */
    541 				if (target_level == 0) {
    542 					target_level = ntohl(group);
    543 					ask2(target_addr);
    544 				}
    545 			} else {
    546 				accept_neighbors(src, dst, (u_char *)(igmp + 1),
    547 						 igmpdatalen, ntohl(group));
    548 				exit(0);
    549 			}
    550 			break;
    551 
    552 		case DVMRP_NEIGHBORS2:
    553 			accept_neighbors2(src, dst, (u_char *)(igmp + 1),
    554 					  igmpdatalen, ntohl(group));
    555 			exit(0);
    556 		}
    557 	    }
    558 	}
    559 	exit(1);
    560 }
    561 
    562 /* dummies */
    563 void accept_probe(src, dst, p, datalen, level)
    564 	u_int32_t src, dst, level;
    565 	char *p;
    566 	int datalen;
    567 {
    568 }
    569 void accept_group_report(src, dst, group, r_type)
    570 	u_int32_t src, dst, group;
    571 	int r_type;
    572 {
    573 }
    574 void accept_neighbor_request2(src, dst)
    575 	u_int32_t src, dst;
    576 {
    577 }
    578 void accept_report(src, dst, p, datalen, level)
    579 	u_int32_t src, dst, level;
    580 	char *p;
    581 	int datalen;
    582 {
    583 }
    584 void accept_neighbor_request(src, dst)
    585 	u_int32_t src, dst;
    586 {
    587 }
    588 void accept_prune(src, dst, p, datalen)
    589 	u_int32_t src, dst;
    590 	char *p;
    591 	int datalen;
    592 {
    593 }
    594 void accept_graft(src, dst, p, datalen)
    595 	u_int32_t src, dst;
    596 	char *p;
    597 	int datalen;
    598 {
    599 }
    600 void accept_g_ack(src, dst, p, datalen)
    601 	u_int32_t src, dst;
    602 	char *p;
    603 	int datalen;
    604 {
    605 }
    606 void add_table_entry(origin, mcastgrp)
    607 	u_int32_t origin, mcastgrp;
    608 {
    609 }
    610 void check_vif_state()
    611 {
    612 }
    613 void accept_leave_message(src, dst, group)
    614 	u_int32_t src, dst, group;
    615 {
    616 }
    617 void accept_mtrace(src, dst, group, data, no, datalen)
    618 	u_int32_t src, dst, group;
    619 	char *data;
    620 	u_int no;
    621 	int datalen;
    622 {
    623 }
    624 void accept_membership_query(src, dst, group, tmo)
    625 	u_int32_t src, dst, group;
    626 	int tmo;
    627 {
    628 }
    629 void accept_info_request(src, dst, p, datalen)
    630 	u_int32_t src, dst;
    631 	u_char *p;
    632 	int datalen;
    633 {
    634 }
    635 void accept_info_reply(src, dst, p, datalen)
    636 	u_int32_t src, dst;
    637 	u_char *p;
    638 	int datalen;
    639 {
    640 }
    641