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      1 /*	$NetBSD: fingerd.c,v 1.27 2012/03/15 02:02:21 joerg Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1983, 1993
      5  *	The 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. Neither the name of the University nor the names of its contributors
     16  *    may be used to endorse or promote products derived from this software
     17  *    without specific prior written permission.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     29  * SUCH DAMAGE.
     30  */
     31 
     32 #include <sys/cdefs.h>
     33 #ifndef lint
     34 __COPYRIGHT("@(#) Copyright (c) 1983, 1993\
     35  The Regents of the University of California.  All rights reserved.");
     36 #endif /* not lint */
     37 
     38 #ifndef lint
     39 #if 0
     40 static char sccsid[] = "from: @(#)fingerd.c	8.1 (Berkeley) 6/4/93";
     41 #else
     42 __RCSID("$NetBSD: fingerd.c,v 1.27 2012/03/15 02:02:21 joerg Exp $");
     43 #endif
     44 #endif /* not lint */
     45 
     46 #include <sys/param.h>
     47 #include <sys/socket.h>
     48 #include <netinet/in.h>
     49 #include <arpa/inet.h>
     50 #include <errno.h>
     51 
     52 #include <unistd.h>
     53 #include <syslog.h>
     54 #include <netdb.h>
     55 #include <stdarg.h>
     56 #include <stdio.h>
     57 #include <stdlib.h>
     58 #include <string.h>
     59 #include "pathnames.h"
     60 
     61 __dead static void my_err(const char *, ...) __printflike(1, 2);
     62 
     63 int
     64 main(int argc, char *argv[])
     65 {
     66 	FILE *fp;
     67 	int ch, ac = 2;
     68 	char *lp = NULL /* XXX gcc */;
     69 	struct sockaddr_storage ss;
     70 	int p[2], logging, no_forward, user_required, short_list;
     71 	socklen_t sval;
     72 #define	ENTRIES	50
     73 	char **ap, *av[ENTRIES + 1], **comp, line[1024], *prog, *s;
     74 #if 0
     75 	const char *av[ENTRIES + 1], **comp;
     76 	const char *prog;
     77 #endif
     78 	char hostbuf[MAXHOSTNAMELEN];
     79 
     80 	prog = __UNCONST(_PATH_FINGER);
     81 	logging = no_forward = user_required = short_list = 0;
     82 	openlog("fingerd", LOG_PID, LOG_DAEMON);
     83 	opterr = 0;
     84 	while ((ch = getopt(argc, argv, "gsluShmpP:8")) != -1) {
     85 		switch (ch) {
     86 		case 'l':
     87 			logging = 1;
     88 			break;
     89 		case 'P':
     90 			prog = optarg;
     91 			break;
     92 		case 's':
     93 			no_forward = 1;
     94 			break;
     95 		case 'u':
     96 			user_required = 1;
     97 			break;
     98 		case 'S':
     99 			short_list = 1;
    100 			av[ac++] = __UNCONST("-s");
    101 			break;
    102 		case 'h':
    103 			av[ac++] = __UNCONST("-h");
    104 			break;
    105 		case 'm':
    106 			av[ac++] = __UNCONST("-m");
    107 			break;
    108 		case 'p':
    109 			av[ac++] = __UNCONST("-p");
    110 			break;
    111 		case 'g':
    112 			av[ac++] = __UNCONST("-g");
    113 			break;
    114 		case '8':
    115 			av[ac++] = __UNCONST("-8");
    116 			break;
    117 		case '?':
    118 		default:
    119 			my_err("illegal option -- %c", optopt);
    120 		}
    121 		if (ac >= ENTRIES)
    122 			my_err("Too many options provided");
    123 	}
    124 
    125 
    126 	if (logging) {
    127 		sval = sizeof(ss);
    128 		if (getpeername(0, (struct sockaddr *)&ss, &sval) < 0)
    129 			my_err("getpeername: %s", strerror(errno));
    130 		(void)getnameinfo((struct sockaddr *)&ss, sval,
    131 				hostbuf, sizeof(hostbuf), NULL, 0, 0);
    132 		lp = hostbuf;
    133 	}
    134 
    135 	if (!fgets(line, sizeof(line), stdin)) {
    136 		if (logging)
    137 			syslog(LOG_NOTICE, "query from %s", lp);
    138 		exit(1);
    139 	}
    140 	while ((s = strrchr(line, '\n')) != NULL ||
    141 	    (s = strrchr(line, '\r')) != NULL)
    142 		*s = '\0';
    143 
    144 	if (logging) {
    145 		if (*line == '\0')
    146 			syslog(LOG_NOTICE, "query from %s", lp);
    147 		else
    148 			syslog(LOG_NOTICE, "query from %s: %s", lp, line);
    149 	}
    150 
    151 	if (ac >= ENTRIES)
    152 		my_err("Too many options provided");
    153 	av[ac++] = __UNCONST("--");
    154 	comp = &av[1];
    155 	for (lp = line, ap = &av[ac]; ac < ENTRIES;) {
    156 		if ((*ap = strtok(lp, " \t\r\n")) == NULL)
    157 			break;
    158 		lp = NULL;
    159 		if (no_forward && strchr(*ap, '@')) {
    160 			(void) puts("forwarding service denied\r\n");
    161 			exit(1);
    162 		}
    163 
    164 		ch = strlen(*ap);
    165 		while ((*ap)[ch-1] == '@')
    166 			(*ap)[--ch] = '\0';
    167 		if (**ap == '\0')
    168 			continue;
    169 
    170 		/* RFC1196: "/[Ww]" == "-l" */
    171 		if ((*ap)[0] == '/' && ((*ap)[1] == 'W' || (*ap)[1] == 'w')) {
    172 			if (!short_list) {
    173 				av[1] = __UNCONST("-l");
    174 				comp = &av[0];
    175 			}
    176 		} else {
    177 			ap++;
    178 			ac++;
    179 		}
    180 	}
    181 	av[ENTRIES - 1] = NULL;
    182 
    183 	if ((lp = strrchr(prog, '/')))
    184 		*comp = ++lp;
    185 	else
    186 		*comp = prog;
    187 
    188 	if (user_required) {
    189 		for (ap = comp + 1; strcmp("--", *(ap++)); );
    190 		if (*ap == NULL) {
    191 			(void) puts("must provide username\r\n");
    192 			exit(1);
    193 		}
    194 	}
    195 
    196 	if (pipe(p) < 0)
    197 		my_err("pipe: %s", strerror(errno));
    198 
    199 	switch(fork()) {
    200 	case 0:
    201 		(void) close(p[0]);
    202 		if (p[1] != 1) {
    203 			(void) dup2(p[1], 1);
    204 			(void) close(p[1]);
    205 		}
    206 		execv(prog, comp);
    207 		my_err("execv: %s: %s", prog, strerror(errno));
    208 		_exit(1);
    209 	case -1:
    210 		my_err("fork: %s", strerror(errno));
    211 	}
    212 	(void) close(p[1]);
    213 	if (!(fp = fdopen(p[0], "r")))
    214 		my_err("fdopen: %s", strerror(errno));
    215 	while ((ch = getc(fp)) != EOF) {
    216 		if (ch == '\n')
    217 			putchar('\r');
    218 		putchar(ch);
    219 	}
    220 	exit(0);
    221 }
    222 
    223 static void
    224 my_err(const char *fmt, ...)
    225 {
    226 	va_list ap;
    227 
    228 	va_start(ap, fmt);
    229 	(void) vsyslog(LOG_ERR, fmt, ap);
    230 	va_end(ap);
    231 	exit(1);
    232 	/* NOTREACHED */
    233 }
    234