fingerd.c revision 1.14
1/* $OpenBSD: fingerd.c,v 1.14 1999/07/03 18:24:13 deraadt 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. 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#ifndef lint 37static char copyright[] = 38"@(#) Copyright (c) 1983, 1993\n\ 39 The Regents of the University of California. All rights reserved.\n"; 40#endif /* not lint */ 41 42#ifndef lint 43#if 0 44static char sccsid[] = "from: @(#)fingerd.c 8.1 (Berkeley) 6/4/93"; 45#else 46static char rcsid[] = "$OpenBSD: fingerd.c,v 1.14 1999/07/03 18:24:13 deraadt Exp $"; 47#endif 48#endif /* not lint */ 49 50#include <sys/types.h> 51#include <sys/socket.h> 52#include <netinet/in.h> 53#include <arpa/inet.h> 54#include <errno.h> 55 56#include <unistd.h> 57#include <syslog.h> 58#include <netdb.h> 59#include <stdio.h> 60#include <stdlib.h> 61#include <string.h> 62#include "pathnames.h" 63 64void err __P((const char *, ...)); 65 66int 67main(argc, argv) 68 int argc; 69 char *argv[]; 70{ 71 register FILE *fp; 72 register int ch, ac = 2; 73 int p[2], logging, secure, user_required, short_list; 74 size_t linesiz; 75#define ENTRIES 50 76 char **ap, *av[ENTRIES + 1], **comp, *line, *prog, *lp, *hname; 77 char hostbuf[MAXHOSTNAMELEN]; 78 79 prog = _PATH_FINGER; 80 logging = secure = user_required = short_list = 0; 81 openlog("fingerd", LOG_PID, LOG_DAEMON); 82 opterr = 0; 83 while ((ch = getopt(argc, argv, "sluSmMpP:")) != -1) 84 switch (ch) { 85 case 'l': 86 logging = 1; 87 break; 88 case 'P': 89 prog = optarg; 90 break; 91 case 's': 92 secure = 1; 93 break; 94 case 'u': 95 user_required = 1; 96 break; 97 case 'S': 98 short_list = 1; 99 av[ac++] = "-s"; 100 break; 101 case 'm': 102 av[ac++] = "-m"; 103 break; 104 case 'M': 105 av[ac++] = "-M"; 106 break; 107 case 'p': 108 av[ac++] = "-p"; 109 break; 110 case '?': 111 default: 112 err("illegal option -- %c", ch); 113 } 114 115 if (logging) { 116 struct sockaddr_storage ss; 117 int sval; 118 119 sval = sizeof(ss); 120 if (getpeername(0, (struct sockaddr *)&ss, &sval) < 0) 121 err("getpeername: %s", strerror(errno)); 122 (void)getnameinfo((struct sockaddr *)&ss, ss.ss_len, 123 hostbuf, sizeof(hostbuf), NULL, 0, 0); 124 hname = hostbuf; 125 } 126 127 if ((lp = fgetln(stdin, &linesiz)) == NULL) { 128 if (logging) 129 syslog(LOG_NOTICE, "query from %s: %s", hname, 130 feof(stdin) ? "EOF" : strerror(errno)); 131 exit(1); 132 } 133 if ((line = malloc(linesiz + 1)) == NULL) 134 err("Out of memory"); 135 memcpy(line, lp, linesiz); 136 line[linesiz] = '\0'; 137 138 if (logging) { 139 char *tline; 140 141 if ((tline = strdup(line)) == NULL) 142 err("Out of memory"); 143 /* Replace NULL, \r and \n with ' ' */ 144 for (ch = 0; ch < linesiz; ch++) { 145 if (tline[ch] == '\0' || tline[ch] == '\r' || 146 tline[ch] == '\n') 147 tline[ch] = ' '; 148 } 149 for (lp = tline + linesiz - 1; lp >= tline && *lp == ' '; lp--) 150 *lp = '\0'; 151 syslog(LOG_NOTICE, "query from %s: `%s'", hname, tline); 152 free(tline); 153 } 154 155 /* 156 * Note: we assume that finger(1) will treat "--" as end of 157 * command args (ie: that it uses getopt(3)). 158 */ 159 av[ac++] = "--"; 160 comp = &av[1]; 161 for (lp = line, ap = &av[ac]; ac < ENTRIES;) { 162 if ((*ap = strtok(lp, " \t\r\n")) == NULL) 163 break; 164 lp = NULL; 165 if (secure && strchr(*ap, '@')) { 166 (void) puts("forwarding service denied\r"); 167 exit(1); 168 } 169 170 ch = strlen(*ap); 171 while ((*ap)[ch-1] == '@') 172 (*ap)[--ch] = '\0'; 173 if (**ap == '\0') 174 continue; 175 176 /* RFC1196: "/[Ww]" == "-l" */ 177 if ((*ap)[0] == '/' && ((*ap)[1] == 'W' || (*ap)[1] == 'w')) { 178 if (!short_list) { 179 av[1] = "-l"; 180 comp = &av[0]; 181 } 182 } else { 183 ap++; 184 ac++; 185 } 186 } 187 av[ENTRIES - 1] = NULL; 188 189 if ((lp = strrchr(prog, '/'))) 190 *comp = ++lp; 191 else 192 *comp = prog; 193 194 if (user_required) { 195 for (ap = comp + 1; strcmp("--", *(ap++)); ); 196 if (*ap == NULL) { 197 (void) puts("must provide username\r"); 198 exit(1); 199 } 200 } 201 202 if (pipe(p) < 0) 203 err("pipe: %s", strerror(errno)); 204 205 switch(vfork()) { 206 case 0: 207 (void) close(p[0]); 208 if (p[1] != 1) { 209 (void) dup2(p[1], 1); 210 (void) close(p[1]); 211 } 212 execv(prog, comp); 213 err("execv: %s: %s", prog, strerror(errno)); 214 _exit(1); 215 case -1: 216 err("fork: %s", strerror(errno)); 217 } 218 (void) close(p[1]); 219 if (!(fp = fdopen(p[0], "r"))) 220 err("fdopen: %s", strerror(errno)); 221 while ((ch = getc(fp)) != EOF) { 222 if (ch == '\n') 223 putchar('\r'); 224 putchar(ch); 225 } 226 exit(0); 227} 228 229#ifdef __STDC__ 230#include <stdarg.h> 231#else 232#include <varargs.h> 233#endif 234 235void 236#ifdef __STDC__ 237err(const char *fmt, ...) 238#else 239err(fmt, va_alist) 240 char *fmt; 241 va_dcl 242#endif 243{ 244 va_list ap; 245#ifdef __STDC__ 246 va_start(ap, fmt); 247#else 248 va_start(ap); 249#endif 250 (void) vsyslog(LOG_ERR, fmt, ap); 251 va_end(ap); 252 exit(1); 253 /* NOTREACHED */ 254} 255