fingerd.c revision 1.15
1/* $OpenBSD: fingerd.c,v 1.15 1999/07/20 22:40:37 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 1.15 1999/07/20 22:40:37 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 *, ...)); 65void usage __P((void)); 66 67void 68usage() 69{ 70 syslog(LOG_ERR, 71 "usage: ftpd [-slumMpS] [-P filename]"); 72 exit(2); 73} 74 75 76int 77main(argc, argv) 78 int argc; 79 char *argv[]; 80{ 81 register FILE *fp; 82 register int ch, ac = 2; 83 int p[2], logging, secure, user_required, short_list; 84 size_t linesiz; 85#define ENTRIES 50 86 char **ap, *av[ENTRIES + 1], **comp, *line, *prog, *lp, *hname; 87 char hostbuf[MAXHOSTNAMELEN]; 88 89 prog = _PATH_FINGER; 90 logging = secure = user_required = short_list = 0; 91 openlog("fingerd", LOG_PID, LOG_DAEMON); 92 opterr = 0; 93 while ((ch = getopt(argc, argv, "sluSmMpP:")) != -1) 94 switch (ch) { 95 case 'l': 96 logging = 1; 97 break; 98 case 'P': 99 prog = optarg; 100 break; 101 case 's': 102 secure = 1; 103 break; 104 case 'u': 105 user_required = 1; 106 break; 107 case 'S': 108 short_list = 1; 109 av[ac++] = "-s"; 110 break; 111 case 'm': 112 av[ac++] = "-m"; 113 break; 114 case 'M': 115 av[ac++] = "-M"; 116 break; 117 case 'p': 118 av[ac++] = "-p"; 119 break; 120 case '?': 121 default: 122 usage(); 123 } 124 125 if (logging) { 126 struct sockaddr_storage ss; 127 int sval; 128 129 sval = sizeof(ss); 130 if (getpeername(0, (struct sockaddr *)&ss, &sval) < 0) 131 err("getpeername: %s", strerror(errno)); 132 (void)getnameinfo((struct sockaddr *)&ss, ss.ss_len, 133 hostbuf, sizeof(hostbuf), NULL, 0, 0); 134 hname = hostbuf; 135 } 136 137 if ((lp = fgetln(stdin, &linesiz)) == NULL) { 138 if (logging) 139 syslog(LOG_NOTICE, "query from %s: %s", hname, 140 feof(stdin) ? "EOF" : strerror(errno)); 141 exit(1); 142 } 143 if ((line = malloc(linesiz + 1)) == NULL) 144 err("Out of memory"); 145 memcpy(line, lp, linesiz); 146 line[linesiz] = '\0'; 147 148 if (logging) { 149 char *tline; 150 151 if ((tline = strdup(line)) == NULL) 152 err("Out of memory"); 153 /* Replace NULL, \r and \n with ' ' */ 154 for (ch = 0; ch < linesiz; ch++) { 155 if (tline[ch] == '\0' || tline[ch] == '\r' || 156 tline[ch] == '\n') 157 tline[ch] = ' '; 158 } 159 for (lp = tline + linesiz - 1; lp >= tline && *lp == ' '; lp--) 160 *lp = '\0'; 161 syslog(LOG_NOTICE, "query from %s: `%s'", hname, tline); 162 free(tline); 163 } 164 165 /* 166 * Note: we assume that finger(1) will treat "--" as end of 167 * command args (ie: that it uses getopt(3)). 168 */ 169 av[ac++] = "--"; 170 comp = &av[1]; 171 for (lp = line, ap = &av[ac]; ac < ENTRIES;) { 172 if ((*ap = strtok(lp, " \t\r\n")) == NULL) 173 break; 174 lp = NULL; 175 if (secure && strchr(*ap, '@')) { 176 (void) puts("forwarding service denied\r"); 177 exit(1); 178 } 179 180 ch = strlen(*ap); 181 while ((*ap)[ch-1] == '@') 182 (*ap)[--ch] = '\0'; 183 if (**ap == '\0') 184 continue; 185 186 /* RFC1196: "/[Ww]" == "-l" */ 187 if ((*ap)[0] == '/' && ((*ap)[1] == 'W' || (*ap)[1] == 'w')) { 188 if (!short_list) { 189 av[1] = "-l"; 190 comp = &av[0]; 191 } 192 } else { 193 ap++; 194 ac++; 195 } 196 } 197 av[ENTRIES - 1] = NULL; 198 199 if ((lp = strrchr(prog, '/'))) 200 *comp = ++lp; 201 else 202 *comp = prog; 203 204 if (user_required) { 205 for (ap = comp + 1; strcmp("--", *(ap++)); ); 206 if (*ap == NULL) { 207 (void) puts("must provide username\r"); 208 exit(1); 209 } 210 } 211 212 if (pipe(p) < 0) 213 err("pipe: %s", strerror(errno)); 214 215 switch(vfork()) { 216 case 0: 217 (void) close(p[0]); 218 if (p[1] != 1) { 219 (void) dup2(p[1], 1); 220 (void) close(p[1]); 221 } 222 execv(prog, comp); 223 err("execv: %s: %s", prog, strerror(errno)); 224 _exit(1); 225 case -1: 226 err("fork: %s", strerror(errno)); 227 } 228 (void) close(p[1]); 229 if (!(fp = fdopen(p[0], "r"))) 230 err("fdopen: %s", strerror(errno)); 231 while ((ch = getc(fp)) != EOF) { 232 if (ch == '\n') 233 putchar('\r'); 234 putchar(ch); 235 } 236 exit(0); 237} 238 239#ifdef __STDC__ 240#include <stdarg.h> 241#else 242#include <varargs.h> 243#endif 244 245void 246#ifdef __STDC__ 247err(const char *fmt, ...) 248#else 249err(fmt, va_alist) 250 char *fmt; 251 va_dcl 252#endif 253{ 254 va_list ap; 255#ifdef __STDC__ 256 va_start(ap, fmt); 257#else 258 va_start(ap); 259#endif 260 (void) vsyslog(LOG_ERR, fmt, ap); 261 va_end(ap); 262 exit(1); 263 /* NOTREACHED */ 264} 265