fingerd.c revision 1.11
1/* $OpenBSD: fingerd.c,v 1.11 1997/11/17 00:43:25 millert 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 1.11 1997/11/17 00:43:25 millert 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 78 prog = _PATH_FINGER; 79 logging = secure = user_required = short_list = 0; 80 openlog("fingerd", LOG_PID | LOG_CONS, LOG_DAEMON); 81 opterr = 0; 82 while ((ch = getopt(argc, argv, "sluSmMpP:")) != -1) 83 switch (ch) { 84 case 'l': 85 logging = 1; 86 break; 87 case 'P': 88 prog = optarg; 89 break; 90 case 's': 91 secure = 1; 92 break; 93 case 'u': 94 user_required = 1; 95 break; 96 case 'S': 97 short_list = 1; 98 av[ac++] = "-s"; 99 break; 100 case 'm': 101 av[ac++] = "-m"; 102 break; 103 case 'M': 104 av[ac++] = "-M"; 105 break; 106 case 'p': 107 av[ac++] = "-p"; 108 break; 109 case '?': 110 default: 111 err("illegal option -- %c", ch); 112 } 113 114 if (logging) { 115 struct hostent *hp; 116 struct sockaddr_in sin; 117 int sval; 118 119 sval = sizeof(sin); 120 if (getpeername(0, (struct sockaddr *)&sin, &sval) < 0) 121 err("getpeername: %s", strerror(errno)); 122 if ((hp = gethostbyaddr((char *)&sin.sin_addr.s_addr, 123 sizeof(sin.sin_addr.s_addr), AF_INET))) 124 hname = strdup(hp->h_name); 125 else 126 hname = strdup(inet_ntoa(sin.sin_addr)); 127 if (hname == NULL) 128 err("Out of memory"); 129 } 130 131 if ((lp = fgetln(stdin, &linesiz)) == NULL) { 132 if (logging) 133 syslog(LOG_NOTICE, "query from %s: %s", hname, 134 feof(stdin) ? "EOF" : strerror(errno)); 135 exit(1); 136 } 137 if ((line = malloc(linesiz + 1)) == NULL) 138 err("Out of memory"); 139 memcpy(line, lp, linesiz); 140 line[linesiz] = '\0'; 141 142 if (logging) { 143 char *tline; 144 145 if ((tline = strdup(line)) == NULL) 146 err("Out of memory"); 147 /* Replace NULL, \r and \n with ' ' */ 148 for (ch = 0; ch < linesiz; ch++) { 149 if (tline[ch] == '\0' || tline[ch] == '\r' || 150 tline[ch] == '\n') 151 tline[ch] = ' '; 152 } 153 for (lp = tline + linesiz - 1; lp >= tline && *lp == ' '; lp--) 154 *lp = '\0'; 155 syslog(LOG_NOTICE, "query from %s: `%s'", hname, tline); 156 free(tline); 157 } 158 159 /* 160 * Note: we assume that finger(1) will treat "--" as end of 161 * command args (ie: that it uses getopt(3)). 162 */ 163 av[ac++] = "--"; 164 comp = &av[1]; 165 for (lp = line, ap = &av[ac]; ac < ENTRIES;) { 166 if ((*ap = strtok(lp, " \t\r\n")) == NULL) 167 break; 168 lp = NULL; 169 if (secure && strchr(*ap, '@')) { 170 (void) puts("fowarding service denied\r"); 171 exit(1); 172 } 173 174 ch = strlen(*ap); 175 while ((*ap)[ch-1] == '@') 176 (*ap)[--ch] = '\0'; 177 if (**ap == '\0') 178 continue; 179 180 /* RFC1196: "/[Ww]" == "-l" */ 181 if ((*ap)[0] == '/' && ((*ap)[1] == 'W' || (*ap)[1] == 'w')) { 182 if (!short_list) { 183 av[1] = "-l"; 184 comp = &av[0]; 185 } 186 } else { 187 ap++; 188 ac++; 189 } 190 } 191 av[ENTRIES - 1] = NULL; 192 193 if ((lp = strrchr(prog, '/'))) 194 *comp = ++lp; 195 else 196 *comp = prog; 197 198 if (user_required) { 199 for (ap = comp + 1; strcmp("--", *(ap++)); ); 200 if (*ap == NULL) { 201 (void) puts("must provide username\r"); 202 exit(1); 203 } 204 } 205 206 if (pipe(p) < 0) 207 err("pipe: %s", strerror(errno)); 208 209 switch(vfork()) { 210 case 0: 211 (void) close(p[0]); 212 if (p[1] != 1) { 213 (void) dup2(p[1], 1); 214 (void) close(p[1]); 215 } 216 execv(prog, comp); 217 err("execv: %s: %s", prog, strerror(errno)); 218 _exit(1); 219 case -1: 220 err("fork: %s", strerror(errno)); 221 } 222 (void) close(p[1]); 223 if (!(fp = fdopen(p[0], "r"))) 224 err("fdopen: %s", strerror(errno)); 225 while ((ch = getc(fp)) != EOF) { 226 if (ch == '\n') 227 putchar('\r'); 228 putchar(ch); 229 } 230 exit(0); 231} 232 233#ifdef __STDC__ 234#include <stdarg.h> 235#else 236#include <varargs.h> 237#endif 238 239void 240#ifdef __STDC__ 241err(const char *fmt, ...) 242#else 243err(fmt, va_alist) 244 char *fmt; 245 va_dcl 246#endif 247{ 248 va_list ap; 249#ifdef __STDC__ 250 va_start(ap, fmt); 251#else 252 va_start(ap); 253#endif 254 (void) vsyslog(LOG_ERR, fmt, ap); 255 va_end(ap); 256 exit(1); 257 /* NOTREACHED */ 258} 259