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 static char rcsid[] = "$OpenBSD: syslog.c,v 1.13 2001/10/31 14:24:11 fgsch Exp $"; 36 #endif /* LIBC_SCCS and not lint */ 37 38 #include <sys/types.h> 39 #include <sys/socket.h> 40 #include <sys/syslog.h> 41 #include <sys/uio.h> 42 #include <sys/un.h> 43 #include <netdb.h> 44 45 #include <errno.h> 46 #include <fcntl.h> 47 #include <paths.h> 48 #include <stdio.h> 49 #include <string.h> 50 #include <time.h> 51 #include <unistd.h> 52 53 #ifdef __STDC__ 54 #include <stdarg.h> 55 #else 56 #include <varargs.h> 57 #endif 58 59 static struct syslog_data sdata = SYSLOG_DATA_INIT; 60 61 extern char *__progname; /* Program name, from crt0. */ 62 63 static void disconnectlog __P((void)); /* disconnect from syslogd */ 64 static void connectlog __P((void)); /* (re)connect to syslogd */ 65 static void disconnectlog_r __P((struct syslog_data *)); 66 static void connectlog_r __P((struct syslog_data *)); 67 68 /* 69 * syslog, vsyslog -- 70 * print message on log file; output is intended for syslogd(8). 71 */ 72 void 73 #ifdef __STDC__ 74 syslog(int pri, const char *fmt, ...) 75 #else 76 syslog(pri, fmt, va_alist) 77 int pri; 78 char *fmt; 79 va_dcl 80 #endif 81 { 82 va_list ap; 83 84 #ifdef __STDC__ 85 va_start(ap, fmt); 86 #else 87 va_start(ap); 88 #endif 89 vsyslog(pri, fmt, ap); 90 va_end(ap); 91 } 92 93 void 94 vsyslog(pri, fmt, ap) 95 int pri; 96 register const char *fmt; 97 va_list ap; 98 { 99 vsyslog_r(pri, &sdata, fmt, ap); 100 } 101 102 static void 103 disconnectlog() 104 { 105 disconnectlog_r(&sdata); 106 } 107 108 static void 109 connectlog() 110 { 111 connectlog_r(&sdata); 112 } 113 114 void 115 openlog(ident, logstat, logfac) 116 const char *ident; 117 int logstat, logfac; 118 { 119 openlog_r(ident, logstat, logfac, &sdata); 120 } 121 122 void 123 closelog() 124 { 125 closelog_r(&sdata); 126 } 127 128 /* setlogmask -- set the log mask level */ 129 int 130 setlogmask(pmask) 131 int pmask; 132 { 133 return setlogmask_r(pmask, &sdata); 134 } 135 136 /* Reentrant version of syslog, i.e. syslog_r() */ 137 138 void 139 #ifdef __STDC__ 140 syslog_r(int pri, struct syslog_data *data, const char *fmt, ...) 141 #else 142 syslog_r(pri, data, fmt, va_alist) 143 int pri; 144 struct syslog_data *data; 145 char *fmt; 146 va_dcl 147 #endif 148 { 149 va_list ap; 150 151 #ifdef __STDC__ 152 va_start(ap, fmt); 153 #else 154 va_start(ap); 155 #endif 156 vsyslog_r(pri, data, fmt, ap); 157 va_end(ap); 158 } 159 160 void 161 vsyslog_r(pri, data, fmt, ap) 162 int pri; 163 struct syslog_data *data; 164 const char *fmt; 165 va_list ap; 166 { 167 int cnt; 168 char ch, *p, *t; 169 time_t now; 170 int fd, saved_errno; 171 #define TBUF_LEN 2048 172 #define FMT_LEN 1024 173 char *stdp, tbuf[TBUF_LEN], fmt_cpy[FMT_LEN]; 174 int tbuf_left, fmt_left, prlen; 175 176 #define INTERNALLOG LOG_ERR|LOG_CONS|LOG_PERROR|LOG_PID 177 /* Check for invalid bits. */ 178 if (pri & ~(LOG_PRIMASK|LOG_FACMASK)) { 179 if (data == &sdata) { 180 syslog(INTERNALLOG, 181 "syslog: unknown facility/priority: %x", pri); 182 } else { 183 syslog_r(INTERNALLOG, data, 184 "syslog_r: unknown facility/priority: %x", pri); 185 } 186 pri &= LOG_PRIMASK|LOG_FACMASK; 187 } 188 189 /* Check priority against setlogmask values. */ 190 if (!(LOG_MASK(LOG_PRI(pri)) & data->log_mask)) 191 return; 192 193 saved_errno = errno; 194 195 /* Set default facility if none specified. */ 196 if ((pri & LOG_FACMASK) == 0) 197 pri |= data->log_fac; 198 199 /* If we have been called through syslog(), no need for reentrancy. */ 200 if (data == &sdata) 201 (void)time(&now); 202 203 p = tbuf; 204 tbuf_left = TBUF_LEN; 205 206 #define DEC() \ 207 do { \ 208 if (prlen < 0) \ 209 prlen = 0; \ 210 if (prlen >= tbuf_left) \ 211 prlen = tbuf_left - 1; \ 212 p += prlen; \ 213 tbuf_left -= prlen; \ 214 } while (0) 215 216 prlen = snprintf(p, tbuf_left, "<%d>", pri); 217 DEC(); 218 219 /* 220 * syslogd will expand time automagically for reentrant case, and 221 * for normal case, just do like before 222 */ 223 if (data == &sdata) { 224 prlen = strftime(p, tbuf_left, "%h %e %T ", localtime(&now)); 225 DEC(); 226 } 227 228 if (data->log_stat & LOG_PERROR) 229 stdp = p; 230 if (data->log_tag == NULL) 231 data->log_tag = __progname; 232 if (data->log_tag != NULL) { 233 prlen = snprintf(p, tbuf_left, "%s", data->log_tag); 234 DEC(); 235 } 236 if (data->log_stat & LOG_PID) { 237 prlen = snprintf(p, tbuf_left, "[%d]", getpid()); 238 DEC(); 239 } 240 if (data->log_tag != NULL) { 241 if (tbuf_left > 1) { 242 *p++ = ':'; 243 tbuf_left--; 244 } 245 if (tbuf_left > 1) { 246 *p++ = ' '; 247 tbuf_left--; 248 } 249 } 250 251 /* strerror() is not reentrant */ 252 253 for (t = fmt_cpy, fmt_left = FMT_LEN; (ch = *fmt); ++fmt) { 254 if (ch == '%' && fmt[1] == 'm') { 255 ++fmt; 256 if (data == &sdata) { 257 prlen = snprintf(t, fmt_left, "%s", 258 strerror(saved_errno)); 259 } else { 260 prlen = snprintf(t, fmt_left, "Error %d", 261 saved_errno); 262 } 263 if (prlen >= fmt_left) 264 prlen = fmt_left - 1; 265 t += prlen; 266 fmt_left -= prlen; 267 } else { 268 if (fmt_left > 1) { 269 *t++ = ch; 270 fmt_left--; 271 } 272 } 273 } 274 *t = '\0'; 275 276 prlen = vsnprintf(p, tbuf_left, fmt_cpy, ap); 277 DEC(); 278 cnt = p - tbuf; 279 280 /* Output to stderr if requested. */ 281 if (data->log_stat & LOG_PERROR) { 282 struct iovec iov[2]; 283 284 iov[0].iov_base = stdp; 285 iov[0].iov_len = cnt - (stdp - tbuf); 286 iov[1].iov_base = "\n"; 287 iov[1].iov_len = 1; 288 (void)writev(STDERR_FILENO, iov, 2); 289 } 290 291 /* Get connected, output the message to the local logger. */ 292 if (!data->opened) 293 openlog_r(data->log_tag, data->log_stat, 0, data); 294 connectlog_r(data); 295 if (send(data->log_file, tbuf, cnt, 0) >= 0) 296 return; 297 298 /* 299 * If the send() failed, the odds are syslogd was restarted. 300 * Make one (only) attempt to reconnect to /dev/log. 301 */ 302 disconnectlog_r(data); 303 connectlog_r(data); 304 if (send(data->log_file, tbuf, cnt, 0) >= 0) 305 return; 306 307 /* 308 * Output the message to the console; don't worry about blocking, 309 * if console blocks everything will. Make sure the error reported 310 * is the one from the syslogd failure. 311 */ 312 if (data->log_stat & LOG_CONS && 313 (fd = open(_PATH_CONSOLE, O_WRONLY, 0)) >= 0) { 314 struct iovec iov[2]; 315 316 p = strchr(tbuf, '>') + 1; 317 iov[0].iov_base = p; 318 iov[0].iov_len = cnt - (p - tbuf); 319 iov[1].iov_base = "\r\n"; 320 iov[1].iov_len = 2; 321 (void)writev(fd, iov, 2); 322 (void)close(fd); 323 } 324 } 325 326 static void 327 disconnectlog_r(data) 328 struct syslog_data *data; 329 { 330 /* 331 * If the user closed the FD and opened another in the same slot, 332 * that's their problem. They should close it before calling on 333 * system services. 334 */ 335 if (data->log_file != -1) { 336 close(data->log_file); 337 data->log_file = -1; 338 } 339 data->connected = 0; /* retry connect */ 340 } 341 342 static void 343 connectlog_r(data) 344 struct syslog_data *data; 345 { 346 struct sockaddr_un SyslogAddr; /* AF_UNIX address of local logger */ 347 348 if (data->log_file == -1) { 349 if ((data->log_file = socket(AF_UNIX, SOCK_DGRAM, 0)) == -1) 350 return; 351 (void)fcntl(data->log_file, F_SETFD, 1); 352 } 353 if (data->log_file != -1 && !data->connected) { 354 memset(&SyslogAddr, '\0', sizeof(SyslogAddr)); 355 SyslogAddr.sun_len = sizeof(SyslogAddr); 356 SyslogAddr.sun_family = AF_UNIX; 357 strlcpy(SyslogAddr.sun_path, _PATH_LOG, 358 sizeof(SyslogAddr.sun_path)); 359 if (connect(data->log_file, (struct sockaddr *)&SyslogAddr, 360 sizeof(SyslogAddr)) == -1) { 361 (void)close(data->log_file); 362 data->log_file = -1; 363 } else 364 data->connected = 1; 365 } 366 } 367 368 void 369 openlog_r(ident, logstat, logfac, data) 370 const char *ident; 371 int logstat, logfac; 372 struct syslog_data *data; 373 { 374 if (ident != NULL) 375 data->log_tag = ident; 376 data->log_stat = logstat; 377 if (logfac != 0 && (logfac &~ LOG_FACMASK) == 0) 378 data->log_fac = logfac; 379 380 if (data->log_stat & LOG_NDELAY) /* open immediately */ 381 connectlog_r(data); 382 383 data->opened = 1; /* ident and facility has been set */ 384 } 385 386 void 387 closelog_r(data) 388 struct syslog_data *data; 389 { 390 (void)close(data->log_file); 391 data->log_file = -1; 392 data->connected = 0; 393 } 394 395 /* setlogmask -- set the log mask level */ 396 int 397 setlogmask_r(pmask, data) 398 int pmask; 399 struct syslog_data *data; 400 { 401 int omask; 402 403 omask = data->log_mask; 404 if (pmask != 0) 405 data->log_mask = pmask; 406 return (omask); 407 } 408