1 /* 2 * Copyright (c) 1983, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #ifndef lint 35 static const char copyright[] = 36 "@(#) Copyright (c) 1983, 1993\n\ 37 The Regents of the University of California. All rights reserved.\n"; 38 #endif /* not lint */ 39 40 #ifndef lint 41 #if 0 42 static char sccsid[] = "@(#)fingerd.c 8.1 (Berkeley) 6/4/93"; 43 #endif 44 static const char rcsid[] = 45 "$FreeBSD$"; 46 #endif /* not lint */ 47 48 #include <sys/types.h> 49 #include <sys/param.h> 50 #include <sys/socket.h> 51 #include <netinet/in.h> 52 #include <netinet/tcp.h> 53 #include <arpa/inet.h> 54 #include <errno.h> 55 56 #include <unistd.h> 57 #include <syslog.h> 58 #include <libutil.h> 59 #include <netdb.h> 60 #include <stdio.h> 61 #include <stdlib.h> 62 #include <string.h> 63 #include "pathnames.h" 64 65 void logerr(const char *, ...) __printflike(1, 2) __dead2; 66 67 int 68 main(int argc, char *argv[]) 69 { 70 FILE *fp; 71 int ch; 72 char *lp; 73 struct sockaddr_storage ss; 74 socklen_t sval; 75 int p[2], logging, pflag, secure; 76 #define ENTRIES 50 77 char **ap, *av[ENTRIES + 1], **comp, line[1024], *prog; 78 char rhost[MAXHOSTNAMELEN]; 79 80 prog = _PATH_FINGER; 81 logging = pflag = secure = 0; 82 openlog("fingerd", LOG_PID | LOG_CONS, LOG_DAEMON); 83 opterr = 0; 84 while ((ch = getopt(argc, argv, "lp:s")) != -1) 85 switch (ch) { 86 case 'l': 87 logging = 1; 88 break; 89 case 'p': 90 prog = optarg; 91 pflag = 1; 92 break; 93 case 's': 94 secure = 1; 95 break; 96 case '?': 97 default: 98 logerr("illegal option -- %c", optopt); 99 } 100 101 /* 102 * Enable server-side Transaction TCP. 103 */ 104 { 105 int one = 1; 106 if (setsockopt(STDOUT_FILENO, IPPROTO_TCP, TCP_NOPUSH, &one, 107 sizeof one) < 0) { 108 logerr("setsockopt(TCP_NOPUSH) failed: %m"); 109 } 110 } 111 112 if (!fgets(line, sizeof(line), stdin)) 113 exit(1); 114 115 if (logging || pflag) { 116 sval = sizeof(ss); 117 if (getpeername(0, (struct sockaddr *)&ss, &sval) < 0) 118 logerr("getpeername: %s", strerror(errno)); 119 realhostname_sa(rhost, sizeof rhost - 1, 120 (struct sockaddr *)&ss, sval); 121 rhost[sizeof(rhost) - 1] = '\0'; 122 if (pflag) 123 setenv("FINGERD_REMOTE_HOST", rhost, 1); 124 } 125 126 if (logging) { 127 char *t; 128 char *end; 129 130 end = memchr(line, 0, sizeof(line)); 131 if (end == NULL) { 132 if ((t = malloc(sizeof(line) + 1)) == NULL) 133 logerr("malloc: %s", strerror(errno)); 134 memcpy(t, line, sizeof(line)); 135 t[sizeof(line)] = 0; 136 } else { 137 if ((t = strdup(line)) == NULL) 138 logerr("strdup: %s", strerror(errno)); 139 } 140 for (end = t; *end; end++) 141 if (*end == '\n' || *end == '\r') 142 *end = ' '; 143 syslog(LOG_NOTICE, "query from %s: `%s'", rhost, t); 144 } 145 146 comp = &av[1]; 147 av[2] = "--"; 148 for (lp = line, ap = &av[3];;) { 149 *ap = strtok(lp, " \t\r\n"); 150 if (!*ap) { 151 if (secure && ap == &av[3]) { 152 puts("must provide username\r\n"); 153 exit(1); 154 } 155 break; 156 } 157 if (secure && strchr(*ap, '@')) { 158 puts("forwarding service denied\r\n"); 159 exit(1); 160 } 161 162 /* RFC742: "/[Ww]" == "-l" */ 163 if ((*ap)[0] == '/' && ((*ap)[1] == 'W' || (*ap)[1] == 'w')) { 164 av[1] = "-l"; 165 comp = &av[0]; 166 } 167 else if (++ap == av + ENTRIES) { 168 *ap = NULL; 169 break; 170 } 171 lp = NULL; 172 } 173 174 if ((lp = strrchr(prog, '/')) != NULL) 175 *comp = ++lp; 176 else 177 *comp = prog; 178 if (pipe(p) < 0) 179 logerr("pipe: %s", strerror(errno)); 180 181 switch(vfork()) { 182 case 0: 183 (void)close(p[0]); 184 if (p[1] != STDOUT_FILENO) { 185 (void)dup2(p[1], STDOUT_FILENO); 186 (void)close(p[1]); 187 } 188 dup2(STDOUT_FILENO, STDERR_FILENO); 189 190 execv(prog, comp); 191 write(STDERR_FILENO, prog, strlen(prog)); 192 #define MSG ": cannot execute\n" 193 write(STDERR_FILENO, MSG, strlen(MSG)); 194 #undef MSG 195 _exit(1); 196 case -1: 197 logerr("fork: %s", strerror(errno)); 198 } 199 (void)close(p[1]); 200 if (!(fp = fdopen(p[0], "r"))) 201 logerr("fdopen: %s", strerror(errno)); 202 while ((ch = getc(fp)) != EOF) { 203 if (ch == '\n') 204 putchar('\r'); 205 putchar(ch); 206 } 207 exit(0); 208 } 209 210 #include <stdarg.h> 211 212 void 213 logerr(const char *fmt, ...) 214 { 215 va_list ap; 216 va_start(ap, fmt); 217 (void)vsyslog(LOG_ERR, fmt, ap); 218 va_end(ap); 219 exit(1); 220 /* NOTREACHED */ 221 } 222