1/* $NetBSD: syslog.c,v 1.2 2021/08/14 16:14:58 christos Exp $ */ 2 3/* $OpenBSD: syslog.c,v 1.29 2007/11/09 18:40:19 millert Exp $ */ 4/* 5 * Copyright (c) 1983, 1988, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33#include <sys/cdefs.h> 34__RCSID("$NetBSD: syslog.c,v 1.2 2021/08/14 16:14:58 christos Exp $"); 35 36#include "portable.h" 37 38#include <sys/types.h> 39#include <ac/socket.h> 40#include <ac/syslog.h> 41#include <sys/uio.h> 42#include <sys/un.h> 43#include <netdb.h> 44 45#include <ac/errno.h> 46#include <fcntl.h> 47#include <paths.h> 48#include <stdio.h> 49#include <ac/string.h> 50#include <ac/time.h> 51#include <ac/unistd.h> 52#include <ac/stdarg.h> 53 54#include "slap.h" 55#include "lutil.h" 56 57static int LogType = SOCK_DGRAM; /* type of socket connection */ 58static int LogFile = -1; /* fd for log */ 59static int connected; /* have done connect */ 60static int LogStat; /* status bits, set by openlog() */ 61static const char *LogTag; /* string to tag the entry with */ 62static int LogFacility = LOG_USER; /* default facility code */ 63 64static void disconnectlog(void); 65static void connectlog(void); 66 67static void my_localtime(const time_t *t, struct tm *tm); 68 69/* 70 * syslog 71 * print message on log file; output is intended for syslogd(8). 72 */ 73void 74syslog(int pri, const char *fmt, ...) 75{ 76 va_list ap; 77 char *p, *pend; 78#define TBUF_LEN 2048 79#define FMT_LEN 1024 80 char tbuf[TBUF_LEN]; 81 int cnt; 82 int error; 83 int tbuf_left, prlen; 84 85 va_start(ap, fmt); 86 87 /* Check for invalid bits. */ 88 if (pri & ~(LOG_PRIMASK|LOG_FACMASK)) { 89 if (LogTest(LOG_ERR)) 90 lutil_debug(slap_debug, LOG_ERR, 91 "syslog: unknown facility/priority: %x", pri); 92 pri &= LOG_PRIMASK|LOG_FACMASK; 93 } 94 95 /* Set default facility if none specified. */ 96 if ((pri & LOG_FACMASK) == 0) 97 pri |= LogFacility; 98 99 p = tbuf; 100 pend = p + TBUF_LEN; 101 102 *p++ = '<'; 103 p += sprintf(p, "%d", pri); 104 *p++ = '>'; 105 106#if 0 107 (void)time(&now); 108 my_localtime(&now, &tm); 109 p += strftime(p, tbuf_left, "%h %e %T ", &tm); 110#endif 111 112 if (LogTag != NULL) { 113 p = lutil_strcopy(p, LogTag); 114 } 115 if (LogStat & LOG_PID) { 116 *p++ = '['; 117 p += sprintf(p, "%ld", (long)getpid()); 118 *p++ = ']'; 119 } 120 if (LogTag != NULL) { 121 *p++ = ':'; 122 *p++ = ' '; 123 } 124 125 tbuf_left = pend - p; 126 prlen = vsnprintf(p, tbuf_left, fmt, ap); 127 va_end(ap); 128 if (prlen < 0) 129 prlen = 0; 130 else if (prlen >= tbuf_left) 131 prlen = tbuf_left - 1; 132 p += prlen; 133 cnt = p - tbuf; 134 135 /* Get connected, output the message to the local logger. */ 136 if (LogFile == -1) 137 openlog(LogTag, LogStat, 0); 138 connectlog(); 139 140 /* 141 * If the send() failed, there are two likely scenarios: 142 * 1) syslogd was restarted 143 * 2) /dev/log is out of socket buffer space 144 * We attempt to reconnect to /dev/log to take care of 145 * case #1 and keep send()ing data to cover case #2 146 * to give syslogd a chance to empty its socket buffer. 147 */ 148 if ((error = send(LogFile, tbuf, cnt, 0)) < 0) { 149 if (errno != ENOBUFS) { 150 disconnectlog(); 151 connectlog(); 152 } 153 do { 154 usleep(1); 155 if ((error = send(LogFile, tbuf, cnt, 0)) >= 0) 156 break; 157 } while (errno == ENOBUFS); 158 } 159} 160 161static void 162disconnectlog(void) 163{ 164 /* 165 * If the user closed the FD and opened another in the same slot, 166 * that's their problem. They should close it before calling on 167 * system services. 168 */ 169 if (LogFile != -1) { 170 close(LogFile); 171 LogFile = -1; 172 } 173 connected = 0; /* retry connect */ 174} 175 176static void 177connectlog(void) 178{ 179 struct sockaddr_un SyslogAddr; /* AF_UNIX address of local logger */ 180 181 if (LogFile == -1) { 182 if ((LogFile = socket(AF_UNIX, LogType, 0)) == -1) 183 return; 184 (void)fcntl(LogFile, F_SETFD, FD_CLOEXEC); 185 } 186 if (LogFile != -1 && !connected) { 187 memset(&SyslogAddr, '\0', sizeof(SyslogAddr)); 188#ifdef _BSD 189 SyslogAddr.sun_len = sizeof(SyslogAddr); 190#endif 191 SyslogAddr.sun_family = AF_UNIX; 192 strncpy(SyslogAddr.sun_path, _PATH_LOG, 193 sizeof(SyslogAddr.sun_path)); 194 if (connect(LogFile, (struct sockaddr *)&SyslogAddr, 195 sizeof(SyslogAddr)) == -1) { 196 (void)close(LogFile); 197 LogFile = -1; 198 } else 199 connected = 1; 200 } 201} 202 203void 204openlog(const char *ident, int logstat, int logfac) 205{ 206 if (ident != NULL) 207 LogTag = ident; 208 LogStat = logstat; 209 if (logfac != 0 && (logfac &~ LOG_FACMASK) == 0) 210 LogFacility = logfac; 211 212 if (LogStat & LOG_NDELAY) /* open immediately */ 213 connectlog(); 214} 215 216void 217closelog() 218{ 219 (void)close(LogFile); 220 LogFile = -1; 221 connected = 0; 222 LogTag = NULL; 223} 224 225#if 0 226#define SECS_PER_HOUR (60 * 60) 227#define SECS_PER_DAY (SECS_PER_HOUR * 24) 228 229/* How many days come before each month (0-12). */ 230static const unsigned short int __mon_yday[2][13] = 231 { 232 /* Normal years. */ 233 { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 }, 234 /* Leap years. */ 235 { 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 } 236 }; 237 238/* Compute the `struct tm' representation of *T, 239 and store year, yday, mon, mday, wday, hour, min, sec into *TP */ 240static void my_localtime(const time_t *t, struct tm *tm) 241{ 242 time_t days, rem, y; 243 const unsigned short int *ip; 244 int leap; 245 246 days = *t / SECS_PER_DAY; 247 rem = *t % SECS_PER_DAY; 248 rem -= timezone; 249 while (rem < 0) 250 { 251 rem += SECS_PER_DAY; 252 --days; 253 } 254 while (rem >= SECS_PER_DAY) 255 { 256 rem -= SECS_PER_DAY; 257 ++days; 258 } 259 tm->tm_hour = rem / SECS_PER_HOUR; 260 rem %= SECS_PER_HOUR; 261 tm->tm_min = rem / 60; 262 tm->tm_sec = rem % 60; 263 /* January 1, 1970 was a Thursday. */ 264 tm->tm_wday = (4 + days) % 7; 265 if (tm->tm_wday < 0) 266 tm->tm_wday += 7; 267 y = 1970; 268 269#define DIV(a, b) ((a) / (b) - ((a) % (b) < 0)) 270#define LEAPS_THRU_END_OF(y) (DIV (y, 4) - DIV (y, 100) + DIV (y, 400)) 271#define ISLEAP(y) ((y) % 4 == 0 && ((y) % 100 != 0 || (y) % 400 == 0)) 272 273 leap = ISLEAP(y); 274 while (days < 0 || days >= (leap ? 366 : 365)) 275 { 276 /* Guess a corrected year, assuming 365 days per year. */ 277 time_t yg = y + days / 365 - (days % 365 < 0); 278 279 /* Adjust DAYS and Y to match the guessed year. */ 280 days -= ((yg - y) * 365 281 + LEAPS_THRU_END_OF (yg - 1) 282 - LEAPS_THRU_END_OF (y - 1)); 283 y = yg; 284 } 285 tm->tm_year = y - 1900; 286 tm->tm_yday = days; 287 ip = __mon_yday[leap]; 288 for (y = 11; days < (long int) ip[y]; --y) 289 continue; 290 days -= ip[y]; 291 tm->tm_mon = y; 292 tm->tm_mday = days + 1; 293} 294#endif 295