fingerd.c revision 1.24
1/* $OpenBSD: fingerd.c,v 1.24 2001/12/07 18:45:32 mpech 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 1.24 2001/12/07 18:45:32 mpech 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: fingerd [-slumMpS] [-P filename]"); 72 exit(2); 73} 74 75 76int 77main(argc, argv) 78 int argc; 79 char *argv[]; 80{ 81 FILE *fp; 82 int ch, ac = 2; 83 int p[2], logging, secure, user_required, short_list; 84#define ENTRIES 50 85 char **comp, *prog; 86 char **ap, *av[ENTRIES + 1], line[8192], *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 if (ac < ENTRIES) { 109 short_list = 1; 110 av[ac++] = "-s"; 111 } 112 break; 113 case 'm': 114 if (ac < ENTRIES) 115 av[ac++] = "-m"; 116 break; 117 case 'M': 118 if (ac < ENTRIES) 119 av[ac++] = "-M"; 120 break; 121 case 'p': 122 if (ac < ENTRIES) 123 av[ac++] = "-p"; 124 break; 125 default: 126 usage(); 127 } 128 129 if (logging) { 130 struct sockaddr_storage ss; 131 struct sockaddr *sa; 132 int sval; 133 134 sval = sizeof(ss); 135 if (getpeername(0, (struct sockaddr *)&ss, &sval) < 0) { 136 /* err("getpeername: %s", strerror(errno)); */ 137 exit(1); 138 } 139 sa = (struct sockaddr *)&ss; 140 if (getnameinfo(sa, sa->sa_len, hostbuf, sizeof(hostbuf), 141 NULL, 0, 0) != 0) { 142 strlcpy(hostbuf, "?", sizeof(hostbuf)); 143 } 144 hname = hostbuf; 145 } 146 147 if (fgets(line, sizeof(line), stdin) == NULL) { 148 if (logging) 149 syslog(LOG_NOTICE, "query from %s: %s", hname, 150 feof(stdin) ? "EOF" : strerror(errno)); 151 exit(1); 152 } 153 154 if (logging) 155 syslog(LOG_NOTICE, "query from %s: `%.*s'", hname, 156 (int)strcspn(line, "\r\n"), line); 157 158 /* 159 * Note: we assume that finger(1) will treat "--" as end of 160 * command args (ie: that it uses getopt(3)). 161 */ 162 av[ac++] = "--"; 163 comp = &av[1]; 164 for (lp = line, ap = &av[ac]; ac < ENTRIES;) { 165 if ((*ap = strtok(lp, " \t\r\n")) == NULL) 166 break; 167 lp = NULL; 168 if (secure && strchr(*ap, '@')) { 169 (void) puts("forwarding service denied\r"); 170 exit(1); 171 } 172 173 ch = strlen(*ap); 174 while ((*ap)[ch-1] == '@') 175 (*ap)[--ch] = '\0'; 176 if (**ap == '\0') 177 continue; 178 179 /* RFC1196: "/[Ww]" == "-l" */ 180 if ((*ap)[0] == '/' && ((*ap)[1] == 'W' || (*ap)[1] == 'w')) { 181 if (!short_list) { 182 av[1] = "-l"; 183 comp = &av[0]; 184 } 185 } else { 186 ap++; 187 ac++; 188 } 189 } 190 av[ENTRIES - 1] = NULL; 191 192 if ((lp = strrchr(prog, '/'))) 193 *comp = ++lp; 194 else 195 *comp = prog; 196 197 if (user_required) { 198 for (ap = comp + 1; strcmp("--", *(ap++)); ) 199 ; 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