1 /* 2 * Copyright (c) 1983, 1988, 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 #if defined(LIBC_SCCS) && !defined(lint) 35 /* 36 static char sccsid[] = "@(#)syslog.c 8.5 (Berkeley) 4/29/95"; 37 */ 38 static const char rcsid[] = 39 "$FreeBSD$"; 40 #endif /* LIBC_SCCS and not lint */ 41 42 #include "namespace.h" 43 #include <sys/types.h> 44 #include <sys/socket.h> 45 #include <sys/syslog.h> 46 #include <sys/uio.h> 47 #include <sys/un.h> 48 #include <netdb.h> 49 50 #include <errno.h> 51 #include <fcntl.h> 52 #include <paths.h> 53 #include <stdio.h> 54 #include <string.h> 55 #include <time.h> 56 #include <unistd.h> 57 58 #if __STDC__ 59 #include <stdarg.h> 60 #else 61 #include <varargs.h> 62 #endif 63 #include "un-namespace.h" 64 65 static int LogFile = -1; /* fd for log */ 66 static int connected; /* have done connect */ 67 static int opened; /* have done openlog() */ 68 static int LogStat = 0; /* status bits, set by openlog() */ 69 static const char *LogTag = NULL; /* string to tag the entry with */ 70 static int LogFacility = LOG_USER; /* default facility code */ 71 static int LogMask = 0xff; /* mask of priorities to be logged */ 72 extern char *__progname; /* Program name, from crt0. */ 73 74 static void disconnectlog __P((void)); /* disconnect from syslogd */ 75 static void connectlog __P((void)); /* (re)connect to syslogd */ 76 77 /* 78 * Format of the magic cookie passed through the stdio hook 79 */ 80 struct bufcookie { 81 char *base; /* start of buffer */ 82 int left; 83 }; 84 85 /* 86 * stdio write hook for writing to a static string buffer 87 * XXX: Maybe one day, dynamically allocate it so that the line length 88 * is `unlimited'. 89 */ 90 static 91 int writehook(cookie, buf, len) 92 void *cookie; /* really [struct bufcookie *] */ 93 char *buf; /* characters to copy */ 94 int len; /* length to copy */ 95 { 96 struct bufcookie *h; /* private `handle' */ 97 98 h = (struct bufcookie *)cookie; 99 if (len > h->left) { 100 /* clip in case of wraparound */ 101 len = h->left; 102 } 103 if (len > 0) { 104 (void)memcpy(h->base, buf, len); /* `write' it. */ 105 h->base += len; 106 h->left -= len; 107 } 108 return 0; 109 } 110 111 /* 112 * syslog, vsyslog -- 113 * print message on log file; output is intended for syslogd(8). 114 */ 115 void 116 #if __STDC__ 117 syslog(int pri, const char *fmt, ...) 118 #else 119 syslog(pri, fmt, va_alist) 120 int pri; 121 char *fmt; 122 va_dcl 123 #endif 124 { 125 va_list ap; 126 127 #if __STDC__ 128 va_start(ap, fmt); 129 #else 130 va_start(ap); 131 #endif 132 vsyslog(pri, fmt, ap); 133 va_end(ap); 134 } 135 136 void 137 vsyslog(pri, fmt, ap) 138 int pri; 139 register const char *fmt; 140 va_list ap; 141 { 142 register int cnt; 143 register char ch, *p; 144 time_t now; 145 int fd, saved_errno; 146 char *stdp, tbuf[2048], fmt_cpy[1024], timbuf[26]; 147 FILE *fp, *fmt_fp; 148 struct bufcookie tbuf_cookie; 149 struct bufcookie fmt_cookie; 150 151 #define INTERNALLOG LOG_ERR|LOG_CONS|LOG_PERROR|LOG_PID 152 /* Check for invalid bits. */ 153 if (pri & ~(LOG_PRIMASK|LOG_FACMASK)) { 154 syslog(INTERNALLOG, 155 "syslog: unknown facility/priority: %x", pri); 156 pri &= LOG_PRIMASK|LOG_FACMASK; 157 } 158 159 /* Check priority against setlogmask values. */ 160 if (!(LOG_MASK(LOG_PRI(pri)) & LogMask)) 161 return; 162 163 saved_errno = errno; 164 165 /* Set default facility if none specified. */ 166 if ((pri & LOG_FACMASK) == 0) 167 pri |= LogFacility; 168 169 /* Create the primary stdio hook */ 170 tbuf_cookie.base = tbuf; 171 tbuf_cookie.left = sizeof(tbuf); 172 fp = fwopen(&tbuf_cookie, writehook); 173 if (fp == NULL) 174 return; 175 176 /* Build the message. */ 177 (void)time(&now); 178 (void)fprintf(fp, "<%d>", pri); 179 (void)fprintf(fp, "%.15s ", ctime_r(&now, timbuf) + 4); 180 if (LogStat & LOG_PERROR) { 181 /* Transfer to string buffer */ 182 (void)fflush(fp); 183 stdp = tbuf + (sizeof(tbuf) - tbuf_cookie.left); 184 } 185 if (LogTag == NULL) 186 LogTag = __progname; 187 if (LogTag != NULL) 188 (void)fprintf(fp, "%s", LogTag); 189 if (LogStat & LOG_PID) 190 (void)fprintf(fp, "[%d]", getpid()); 191 if (LogTag != NULL) { 192 (void)fprintf(fp, ": "); 193 } 194 195 /* Check to see if we can skip expanding the %m */ 196 if (strstr(fmt, "%m")) { 197 198 /* Create the second stdio hook */ 199 fmt_cookie.base = fmt_cpy; 200 fmt_cookie.left = sizeof(fmt_cpy) - 1; 201 fmt_fp = fwopen(&fmt_cookie, writehook); 202 if (fmt_fp == NULL) { 203 fclose(fp); 204 return; 205 } 206 207 /* Substitute error message for %m. */ 208 for ( ; (ch = *fmt); ++fmt) 209 if (ch == '%' && fmt[1] == 'm') { 210 ++fmt; 211 fputs(strerror(saved_errno), fmt_fp); 212 } else 213 fputc(ch, fmt_fp); 214 215 /* Null terminate if room */ 216 fputc(0, fmt_fp); 217 fclose(fmt_fp); 218 219 /* Guarantee null termination */ 220 fmt_cpy[sizeof(fmt_cpy) - 1] = '\0'; 221 222 fmt = fmt_cpy; 223 } 224 225 (void)vfprintf(fp, fmt, ap); 226 (void)fclose(fp); 227 228 cnt = sizeof(tbuf) - tbuf_cookie.left; 229 230 /* Output to stderr if requested. */ 231 if (LogStat & LOG_PERROR) { 232 struct iovec iov[2]; 233 register struct iovec *v = iov; 234 235 v->iov_base = stdp; 236 v->iov_len = cnt - (stdp - tbuf); 237 ++v; 238 v->iov_base = "\n"; 239 v->iov_len = 1; 240 (void)_writev(STDERR_FILENO, iov, 2); 241 } 242 243 /* Get connected, output the message to the local logger. */ 244 if (!opened) 245 openlog(LogTag, LogStat | LOG_NDELAY, 0); 246 connectlog(); 247 if (send(LogFile, tbuf, cnt, 0) >= 0) 248 return; 249 250 /* 251 * If the send() failed, the odds are syslogd was restarted. 252 * Make one (only) attempt to reconnect to /dev/log. 253 */ 254 disconnectlog(); 255 connectlog(); 256 if (send(LogFile, tbuf, cnt, 0) >= 0) 257 return; 258 259 /* 260 * Output the message to the console; don't worry about blocking, 261 * if console blocks everything will. Make sure the error reported 262 * is the one from the syslogd failure. 263 */ 264 if (LogStat & LOG_CONS && 265 (fd = _open(_PATH_CONSOLE, O_WRONLY, 0)) >= 0) { 266 struct iovec iov[2]; 267 register struct iovec *v = iov; 268 269 p = strchr(tbuf, '>') + 1; 270 v->iov_base = p; 271 v->iov_len = cnt - (p - tbuf); 272 ++v; 273 v->iov_base = "\r\n"; 274 v->iov_len = 2; 275 (void)_writev(fd, iov, 2); 276 (void)_close(fd); 277 } 278 } 279 static void 280 disconnectlog() 281 { 282 /* 283 * If the user closed the FD and opened another in the same slot, 284 * that's their problem. They should close it before calling on 285 * system services. 286 */ 287 if (LogFile != -1) { 288 _close(LogFile); 289 LogFile = -1; 290 } 291 connected = 0; /* retry connect */ 292 } 293 294 static void 295 connectlog() 296 { 297 struct sockaddr_un SyslogAddr; /* AF_UNIX address of local logger */ 298 299 if (LogFile == -1) { 300 if ((LogFile = _socket(AF_UNIX, SOCK_DGRAM, 0)) == -1) 301 return; 302 (void)_fcntl(LogFile, F_SETFD, 1); 303 } 304 if (LogFile != -1 && !connected) { 305 SyslogAddr.sun_len = sizeof(SyslogAddr); 306 SyslogAddr.sun_family = AF_UNIX; 307 (void)strncpy(SyslogAddr.sun_path, _PATH_LOG, 308 sizeof SyslogAddr.sun_path); 309 connected = _connect(LogFile, (struct sockaddr *)&SyslogAddr, 310 sizeof(SyslogAddr)) != -1; 311 312 if (!connected) { 313 /* 314 * Try the old "/dev/log" path, for backward 315 * compatibility. 316 */ 317 (void)strncpy(SyslogAddr.sun_path, _PATH_OLDLOG, 318 sizeof SyslogAddr.sun_path); 319 connected = _connect(LogFile, 320 (struct sockaddr *)&SyslogAddr, 321 sizeof(SyslogAddr)) != -1; 322 } 323 324 if (!connected) { 325 (void)_close(LogFile); 326 LogFile = -1; 327 } 328 } 329 } 330 331 void 332 openlog(ident, logstat, logfac) 333 const char *ident; 334 int logstat, logfac; 335 { 336 if (ident != NULL) 337 LogTag = ident; 338 LogStat = logstat; 339 if (logfac != 0 && (logfac &~ LOG_FACMASK) == 0) 340 LogFacility = logfac; 341 342 if (LogStat & LOG_NDELAY) /* open immediately */ 343 connectlog(); 344 345 opened = 1; /* ident and facility has been set */ 346 } 347 348 void 349 closelog() 350 { 351 (void)_close(LogFile); 352 LogFile = -1; 353 connected = 0; 354 } 355 356 /* setlogmask -- set the log mask level */ 357 int 358 setlogmask(pmask) 359 int pmask; 360 { 361 int omask; 362 363 omask = LogMask; 364 if (pmask != 0) 365 LogMask = pmask; 366 return (omask); 367 } 368