1 /* $OpenBSD: log.c,v 1.53 2020/10/16 13:24:45 djm Exp $ */ 2 /* 3 * Author: Tatu Ylonen <ylo@cs.hut.fi> 4 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland 5 * All rights reserved 6 * 7 * As far as I am concerned, the code I have written for this software 8 * can be used freely for any purpose. Any derived versions of this 9 * software must be clearly marked as such, and if the derived work is 10 * incompatible with the protocol description in the RFC file, it must be 11 * called by a name other than "ssh" or "Secure Shell". 12 */ 13 /* 14 * Copyright (c) 2000 Markus Friedl. All rights reserved. 15 * 16 * Redistribution and use in source and binary forms, with or without 17 * modification, are permitted provided that the following conditions 18 * are met: 19 * 1. Redistributions of source code must retain the above copyright 20 * notice, this list of conditions and the following disclaimer. 21 * 2. Redistributions in binary form must reproduce the above copyright 22 * notice, this list of conditions and the following disclaimer in the 23 * documentation and/or other materials provided with the distribution. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 26 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 27 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 28 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 29 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 30 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 31 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 32 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 33 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 34 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 35 */ 36 37 #include <sys/types.h> 38 39 #include <fcntl.h> 40 #include <stdarg.h> 41 #include <stdio.h> 42 #include <stdlib.h> 43 #include <string.h> 44 #include <syslog.h> 45 #include <unistd.h> 46 #include <errno.h> 47 #include <vis.h> 48 49 #include "log.h" 50 #include "match.h" 51 52 static LogLevel log_level = SYSLOG_LEVEL_INFO; 53 static int log_on_stderr = 1; 54 static int log_stderr_fd = STDERR_FILENO; 55 static int log_facility = LOG_AUTH; 56 static char *argv0; 57 static log_handler_fn *log_handler; 58 static void *log_handler_ctx; 59 static char **log_verbose; 60 static size_t nlog_verbose; 61 extern char *__progname; 62 63 /* textual representation of log-facilities/levels */ 64 65 static struct { 66 const char *name; 67 SyslogFacility val; 68 } log_facilities[] = { 69 { "DAEMON", SYSLOG_FACILITY_DAEMON }, 70 { "USER", SYSLOG_FACILITY_USER }, 71 { "AUTH", SYSLOG_FACILITY_AUTH }, 72 { "LOCAL0", SYSLOG_FACILITY_LOCAL0 }, 73 { "LOCAL1", SYSLOG_FACILITY_LOCAL1 }, 74 { "LOCAL2", SYSLOG_FACILITY_LOCAL2 }, 75 { "LOCAL3", SYSLOG_FACILITY_LOCAL3 }, 76 { "LOCAL4", SYSLOG_FACILITY_LOCAL4 }, 77 { "LOCAL5", SYSLOG_FACILITY_LOCAL5 }, 78 { "LOCAL6", SYSLOG_FACILITY_LOCAL6 }, 79 { "LOCAL7", SYSLOG_FACILITY_LOCAL7 }, 80 { NULL, SYSLOG_FACILITY_NOT_SET } 81 }; 82 83 static struct { 84 const char *name; 85 LogLevel val; 86 } log_levels[] = 87 { 88 { "QUIET", SYSLOG_LEVEL_QUIET }, 89 { "FATAL", SYSLOG_LEVEL_FATAL }, 90 { "ERROR", SYSLOG_LEVEL_ERROR }, 91 { "INFO", SYSLOG_LEVEL_INFO }, 92 { "VERBOSE", SYSLOG_LEVEL_VERBOSE }, 93 { "DEBUG", SYSLOG_LEVEL_DEBUG1 }, 94 { "DEBUG1", SYSLOG_LEVEL_DEBUG1 }, 95 { "DEBUG2", SYSLOG_LEVEL_DEBUG2 }, 96 { "DEBUG3", SYSLOG_LEVEL_DEBUG3 }, 97 { NULL, SYSLOG_LEVEL_NOT_SET } 98 }; 99 100 LogLevel 101 log_level_get(void) 102 { 103 return log_level; 104 } 105 106 SyslogFacility 107 log_facility_number(char *name) 108 { 109 int i; 110 111 if (name != NULL) 112 for (i = 0; log_facilities[i].name; i++) 113 if (strcasecmp(log_facilities[i].name, name) == 0) 114 return log_facilities[i].val; 115 return SYSLOG_FACILITY_NOT_SET; 116 } 117 118 const char * 119 log_facility_name(SyslogFacility facility) 120 { 121 u_int i; 122 123 for (i = 0; log_facilities[i].name; i++) 124 if (log_facilities[i].val == facility) 125 return log_facilities[i].name; 126 return NULL; 127 } 128 129 LogLevel 130 log_level_number(char *name) 131 { 132 int i; 133 134 if (name != NULL) 135 for (i = 0; log_levels[i].name; i++) 136 if (strcasecmp(log_levels[i].name, name) == 0) 137 return log_levels[i].val; 138 return SYSLOG_LEVEL_NOT_SET; 139 } 140 141 const char * 142 log_level_name(LogLevel level) 143 { 144 u_int i; 145 146 for (i = 0; log_levels[i].name != NULL; i++) 147 if (log_levels[i].val == level) 148 return log_levels[i].name; 149 return NULL; 150 } 151 152 void 153 log_verbose_add(const char *s) 154 { 155 char **tmp; 156 157 /* Ignore failures here */ 158 if ((tmp = recallocarray(log_verbose, nlog_verbose, nlog_verbose + 1, 159 sizeof(*log_verbose))) != NULL) { 160 log_verbose = tmp; 161 if ((log_verbose[nlog_verbose] = strdup(s)) != NULL) 162 nlog_verbose++; 163 } 164 } 165 166 void 167 log_verbose_reset(void) 168 { 169 size_t i; 170 171 for (i = 0; i < nlog_verbose; i++) 172 free(log_verbose[i]); 173 free(log_verbose); 174 log_verbose = NULL; 175 nlog_verbose = 0; 176 } 177 178 /* 179 * Initialize the log. 180 */ 181 182 void 183 log_init(char *av0, LogLevel level, SyslogFacility facility, int on_stderr) 184 { 185 argv0 = av0; 186 187 if (log_change_level(level) != 0) { 188 fprintf(stderr, "Unrecognized internal syslog level code %d\n", 189 (int) level); 190 exit(1); 191 } 192 193 log_handler = NULL; 194 log_handler_ctx = NULL; 195 196 log_on_stderr = on_stderr; 197 if (on_stderr) 198 return; 199 200 switch (facility) { 201 case SYSLOG_FACILITY_DAEMON: 202 log_facility = LOG_DAEMON; 203 break; 204 case SYSLOG_FACILITY_USER: 205 log_facility = LOG_USER; 206 break; 207 case SYSLOG_FACILITY_AUTH: 208 log_facility = LOG_AUTH; 209 break; 210 case SYSLOG_FACILITY_LOCAL0: 211 log_facility = LOG_LOCAL0; 212 break; 213 case SYSLOG_FACILITY_LOCAL1: 214 log_facility = LOG_LOCAL1; 215 break; 216 case SYSLOG_FACILITY_LOCAL2: 217 log_facility = LOG_LOCAL2; 218 break; 219 case SYSLOG_FACILITY_LOCAL3: 220 log_facility = LOG_LOCAL3; 221 break; 222 case SYSLOG_FACILITY_LOCAL4: 223 log_facility = LOG_LOCAL4; 224 break; 225 case SYSLOG_FACILITY_LOCAL5: 226 log_facility = LOG_LOCAL5; 227 break; 228 case SYSLOG_FACILITY_LOCAL6: 229 log_facility = LOG_LOCAL6; 230 break; 231 case SYSLOG_FACILITY_LOCAL7: 232 log_facility = LOG_LOCAL7; 233 break; 234 default: 235 fprintf(stderr, 236 "Unrecognized internal syslog facility code %d\n", 237 (int) facility); 238 exit(1); 239 } 240 } 241 242 int 243 log_change_level(LogLevel new_log_level) 244 { 245 /* no-op if log_init has not been called */ 246 if (argv0 == NULL) 247 return 0; 248 249 switch (new_log_level) { 250 case SYSLOG_LEVEL_QUIET: 251 case SYSLOG_LEVEL_FATAL: 252 case SYSLOG_LEVEL_ERROR: 253 case SYSLOG_LEVEL_INFO: 254 case SYSLOG_LEVEL_VERBOSE: 255 case SYSLOG_LEVEL_DEBUG1: 256 case SYSLOG_LEVEL_DEBUG2: 257 case SYSLOG_LEVEL_DEBUG3: 258 log_level = new_log_level; 259 return 0; 260 default: 261 return -1; 262 } 263 } 264 265 int 266 log_is_on_stderr(void) 267 { 268 return log_on_stderr && log_stderr_fd == STDERR_FILENO; 269 } 270 271 /* redirect what would usually get written to stderr to specified file */ 272 void 273 log_redirect_stderr_to(const char *logfile) 274 { 275 int fd; 276 277 if (logfile == NULL) { 278 if (log_stderr_fd != STDERR_FILENO) { 279 close(log_stderr_fd); 280 log_stderr_fd = STDERR_FILENO; 281 } 282 return; 283 } 284 285 if ((fd = open(logfile, O_WRONLY|O_CREAT|O_APPEND, 0600)) == -1) { 286 fprintf(stderr, "Couldn't open logfile %s: %s\n", logfile, 287 strerror(errno)); 288 exit(1); 289 } 290 log_stderr_fd = fd; 291 } 292 293 #define MSGBUFSIZ 1024 294 295 void 296 set_log_handler(log_handler_fn *handler, void *ctx) 297 { 298 log_handler = handler; 299 log_handler_ctx = ctx; 300 } 301 302 static void 303 do_log(const char *file, const char *func, int line, LogLevel level, 304 int force, const char *fmt, va_list args) 305 { 306 struct syslog_data sdata = SYSLOG_DATA_INIT; 307 char msgbuf[MSGBUFSIZ]; 308 char fmtbuf[MSGBUFSIZ]; 309 char *txt = NULL; 310 int pri = LOG_INFO; 311 int saved_errno = errno; 312 log_handler_fn *tmp_handler; 313 314 if (!force && level > log_level) 315 return; 316 317 switch (level) { 318 case SYSLOG_LEVEL_FATAL: 319 if (!log_on_stderr) 320 txt = "fatal"; 321 pri = LOG_CRIT; 322 break; 323 case SYSLOG_LEVEL_ERROR: 324 if (!log_on_stderr) 325 txt = "error"; 326 pri = LOG_ERR; 327 break; 328 case SYSLOG_LEVEL_INFO: 329 pri = LOG_INFO; 330 break; 331 case SYSLOG_LEVEL_VERBOSE: 332 pri = LOG_INFO; 333 break; 334 case SYSLOG_LEVEL_DEBUG1: 335 txt = "debug1"; 336 pri = LOG_DEBUG; 337 break; 338 case SYSLOG_LEVEL_DEBUG2: 339 txt = "debug2"; 340 pri = LOG_DEBUG; 341 break; 342 case SYSLOG_LEVEL_DEBUG3: 343 txt = "debug3"; 344 pri = LOG_DEBUG; 345 break; 346 default: 347 txt = "internal error"; 348 pri = LOG_ERR; 349 break; 350 } 351 if (txt != NULL && log_handler == NULL) { 352 snprintf(fmtbuf, sizeof(fmtbuf), "%s: %s", txt, fmt); 353 vsnprintf(msgbuf, sizeof(msgbuf), fmtbuf, args); 354 } else { 355 vsnprintf(msgbuf, sizeof(msgbuf), fmt, args); 356 } 357 strnvis(fmtbuf, msgbuf, sizeof(fmtbuf), VIS_SAFE|VIS_OCTAL); 358 if (log_handler != NULL) { 359 /* Avoid recursion */ 360 tmp_handler = log_handler; 361 log_handler = NULL; 362 tmp_handler(file, func, line, level, fmtbuf, log_handler_ctx); 363 log_handler = tmp_handler; 364 } else if (log_on_stderr) { 365 snprintf(msgbuf, sizeof msgbuf, "%.*s\r\n", 366 (int)sizeof msgbuf - 3, fmtbuf); 367 (void)write(log_stderr_fd, msgbuf, strlen(msgbuf)); 368 } else { 369 openlog_r(argv0 ? argv0 : __progname, LOG_PID, log_facility, &sdata); 370 syslog_r(pri, &sdata, "%.500s", fmtbuf); 371 closelog_r(&sdata); 372 } 373 errno = saved_errno; 374 } 375 376 void 377 sshlog(const char *file, const char *func, int line, int showfunc, 378 LogLevel level, const char *fmt, ...) 379 { 380 va_list args; 381 382 va_start(args, fmt); 383 sshlogv(file, func, line, showfunc, level, fmt, args); 384 va_end(args); 385 } 386 387 void 388 sshlogdie(const char *file, const char *func, int line, const char *fmt, ...) 389 { 390 va_list args; 391 392 va_start(args, fmt); 393 sshlogv(file, func, line, 0, SYSLOG_LEVEL_INFO, fmt, args); 394 va_end(args); 395 cleanup_exit(255); 396 } 397 398 void 399 sshsigdie(const char *file, const char *func, int line, const char *fmt, ...) 400 { 401 va_list args; 402 403 va_start(args, fmt); 404 sshlogv(file, func, line, 0, SYSLOG_LEVEL_FATAL, fmt, args); 405 va_end(args); 406 _exit(1); 407 } 408 409 void 410 sshlogv(const char *file, const char *func, int line, int showfunc, 411 LogLevel level, const char *fmt, va_list args) 412 { 413 char tag[128], fmt2[MSGBUFSIZ + 128]; 414 int forced = 0; 415 const char *cp; 416 size_t i; 417 418 snprintf(tag, sizeof(tag), "%.48s:%.48s():%d", 419 (cp = strrchr(file, '/')) == NULL ? file : cp + 1, func, line); 420 for (i = 0; i < nlog_verbose; i++) { 421 if (match_pattern_list(tag, log_verbose[i], 0) == 1) { 422 forced = 1; 423 break; 424 } 425 } 426 427 if (log_handler == NULL && forced) 428 snprintf(fmt2, sizeof(fmt2), "%s: %s", tag, fmt); 429 else if (showfunc) 430 snprintf(fmt2, sizeof(fmt2), "%s: %s", func, fmt); 431 else 432 strlcpy(fmt2, fmt, sizeof(fmt2)); 433 434 do_log(file, func, line, level, forced, fmt2, args); 435 } 436