blob: d9c2d136cc689ace671efd669003feac666740ac [file] [log] [blame]
/* $OpenBSD: log.c,v 1.51 2018/07/27 12:03:17 markus Exp $ */
/*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
* All rights reserved
*
* As far as I am concerned, the code I have written for this software
* can be used freely for any purpose. Any derived versions of this
* software must be clearly marked as such, and if the derived work is
* incompatible with the protocol description in the RFC file, it must be
* called by a name other than "ssh" or "Secure Shell".
*/
/*
* Copyright (c) 2000 Markus Friedl. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "includes.h"
#include <sys/types.h>
#include <fcntl.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <unistd.h>
#include <errno.h>
#if defined(HAVE_STRNVIS) && defined(HAVE_VIS_H) && !defined(BROKEN_STRNVIS)
# include <vis.h>
#endif
#include "log.h"
static LogLevel log_level = SYSLOG_LEVEL_INFO;
static int log_on_stderr = 1;
static int log_stderr_fd = STDERR_FILENO;
static int log_facility = LOG_AUTH;
static char *argv0;
static log_handler_fn *log_handler;
static void *log_handler_ctx;
extern char *__progname;
#define LOG_SYSLOG_VIS (VIS_CSTYLE|VIS_NL|VIS_TAB|VIS_OCTAL)
#define LOG_STDERR_VIS (VIS_SAFE|VIS_OCTAL)
/* textual representation of log-facilities/levels */
static struct {
const char *name;
SyslogFacility val;
} log_facilities[] = {
{ "DAEMON", SYSLOG_FACILITY_DAEMON },
{ "USER", SYSLOG_FACILITY_USER },
{ "AUTH", SYSLOG_FACILITY_AUTH },
#ifdef LOG_AUTHPRIV
{ "AUTHPRIV", SYSLOG_FACILITY_AUTHPRIV },
#endif
{ "LOCAL0", SYSLOG_FACILITY_LOCAL0 },
{ "LOCAL1", SYSLOG_FACILITY_LOCAL1 },
{ "LOCAL2", SYSLOG_FACILITY_LOCAL2 },
{ "LOCAL3", SYSLOG_FACILITY_LOCAL3 },
{ "LOCAL4", SYSLOG_FACILITY_LOCAL4 },
{ "LOCAL5", SYSLOG_FACILITY_LOCAL5 },
{ "LOCAL6", SYSLOG_FACILITY_LOCAL6 },
{ "LOCAL7", SYSLOG_FACILITY_LOCAL7 },
{ NULL, SYSLOG_FACILITY_NOT_SET }
};
static struct {
const char *name;
LogLevel val;
} log_levels[] =
{
{ "QUIET", SYSLOG_LEVEL_QUIET },
{ "FATAL", SYSLOG_LEVEL_FATAL },
{ "ERROR", SYSLOG_LEVEL_ERROR },
{ "INFO", SYSLOG_LEVEL_INFO },
{ "VERBOSE", SYSLOG_LEVEL_VERBOSE },
{ "DEBUG", SYSLOG_LEVEL_DEBUG1 },
{ "DEBUG1", SYSLOG_LEVEL_DEBUG1 },
{ "DEBUG2", SYSLOG_LEVEL_DEBUG2 },
{ "DEBUG3", SYSLOG_LEVEL_DEBUG3 },
{ NULL, SYSLOG_LEVEL_NOT_SET }
};
LogLevel
log_level_get(void)
{
return log_level;
}
SyslogFacility
log_facility_number(char *name)
{
int i;
if (name != NULL)
for (i = 0; log_facilities[i].name; i++)
if (strcasecmp(log_facilities[i].name, name) == 0)
return log_facilities[i].val;
return SYSLOG_FACILITY_NOT_SET;
}
const char *
log_facility_name(SyslogFacility facility)
{
u_int i;
for (i = 0; log_facilities[i].name; i++)
if (log_facilities[i].val == facility)
return log_facilities[i].name;
return NULL;
}
LogLevel
log_level_number(char *name)
{
int i;
if (name != NULL)
for (i = 0; log_levels[i].name; i++)
if (strcasecmp(log_levels[i].name, name) == 0)
return log_levels[i].val;
return SYSLOG_LEVEL_NOT_SET;
}
const char *
log_level_name(LogLevel level)
{
u_int i;
for (i = 0; log_levels[i].name != NULL; i++)
if (log_levels[i].val == level)
return log_levels[i].name;
return NULL;
}
/* Error messages that should be logged. */
void
error(const char *fmt,...)
{
va_list args;
va_start(args, fmt);
do_log(SYSLOG_LEVEL_ERROR, fmt, args);
va_end(args);
}
void
sigdie(const char *fmt,...)
{
#ifdef DO_LOG_SAFE_IN_SIGHAND
va_list args;
va_start(args, fmt);
do_log(SYSLOG_LEVEL_FATAL, fmt, args);
va_end(args);
#endif
_exit(1);
}
void
logdie(const char *fmt,...)
{
va_list args;
va_start(args, fmt);
do_log(SYSLOG_LEVEL_INFO, fmt, args);
va_end(args);
cleanup_exit(255);
}
/* Log this message (information that usually should go to the log). */
void
logit(const char *fmt,...)
{
va_list args;
va_start(args, fmt);
do_log(SYSLOG_LEVEL_INFO, fmt, args);
va_end(args);
}
/* More detailed messages (information that does not need to go to the log). */
void
verbose(const char *fmt,...)
{
va_list args;
va_start(args, fmt);
do_log(SYSLOG_LEVEL_VERBOSE, fmt, args);
va_end(args);
}
/* Debugging messages that should not be logged during normal operation. */
void
debug(const char *fmt,...)
{
va_list args;
va_start(args, fmt);
do_log(SYSLOG_LEVEL_DEBUG1, fmt, args);
va_end(args);
}
void
debug2(const char *fmt,...)
{
va_list args;
va_start(args, fmt);
do_log(SYSLOG_LEVEL_DEBUG2, fmt, args);
va_end(args);
}
void
debug3(const char *fmt,...)
{
va_list args;
va_start(args, fmt);
do_log(SYSLOG_LEVEL_DEBUG3, fmt, args);
va_end(args);
}
/*
* Initialize the log.
*/
void
log_init(char *av0, LogLevel level, SyslogFacility facility, int on_stderr)
{
#if defined(HAVE_OPENLOG_R) && defined(SYSLOG_DATA_INIT)
struct syslog_data sdata = SYSLOG_DATA_INIT;
#endif
argv0 = av0;
if (log_change_level(level) != 0) {
fprintf(stderr, "Unrecognized internal syslog level code %d\n",
(int) level);
exit(1);
}
log_handler = NULL;
log_handler_ctx = NULL;
log_on_stderr = on_stderr;
if (on_stderr)
return;
switch (facility) {
case SYSLOG_FACILITY_DAEMON:
log_facility = LOG_DAEMON;
break;
case SYSLOG_FACILITY_USER:
log_facility = LOG_USER;
break;
case SYSLOG_FACILITY_AUTH:
log_facility = LOG_AUTH;
break;
#ifdef LOG_AUTHPRIV
case SYSLOG_FACILITY_AUTHPRIV:
log_facility = LOG_AUTHPRIV;
break;
#endif
case SYSLOG_FACILITY_LOCAL0:
log_facility = LOG_LOCAL0;
break;
case SYSLOG_FACILITY_LOCAL1:
log_facility = LOG_LOCAL1;
break;
case SYSLOG_FACILITY_LOCAL2:
log_facility = LOG_LOCAL2;
break;
case SYSLOG_FACILITY_LOCAL3:
log_facility = LOG_LOCAL3;
break;
case SYSLOG_FACILITY_LOCAL4:
log_facility = LOG_LOCAL4;
break;
case SYSLOG_FACILITY_LOCAL5:
log_facility = LOG_LOCAL5;
break;
case SYSLOG_FACILITY_LOCAL6:
log_facility = LOG_LOCAL6;
break;
case SYSLOG_FACILITY_LOCAL7:
log_facility = LOG_LOCAL7;
break;
default:
fprintf(stderr,
"Unrecognized internal syslog facility code %d\n",
(int) facility);
exit(1);
}
/*
* If an external library (eg libwrap) attempts to use syslog
* immediately after reexec, syslog may be pointing to the wrong
* facility, so we force an open/close of syslog here.
*/
#if defined(HAVE_OPENLOG_R) && defined(SYSLOG_DATA_INIT)
openlog_r(argv0 ? argv0 : __progname, LOG_PID, log_facility, &sdata);
closelog_r(&sdata);
#else
openlog(argv0 ? argv0 : __progname, LOG_PID, log_facility);
closelog();
#endif
}
int
log_change_level(LogLevel new_log_level)
{
/* no-op if log_init has not been called */
if (argv0 == NULL)
return 0;
switch (new_log_level) {
case SYSLOG_LEVEL_QUIET:
case SYSLOG_LEVEL_FATAL:
case SYSLOG_LEVEL_ERROR:
case SYSLOG_LEVEL_INFO:
case SYSLOG_LEVEL_VERBOSE:
case SYSLOG_LEVEL_DEBUG1:
case SYSLOG_LEVEL_DEBUG2:
case SYSLOG_LEVEL_DEBUG3:
log_level = new_log_level;
return 0;
default:
return -1;
}
}
int
log_is_on_stderr(void)
{
return log_on_stderr && log_stderr_fd == STDERR_FILENO;
}
/* redirect what would usually get written to stderr to specified file */
void
log_redirect_stderr_to(const char *logfile)
{
int fd;
if ((fd = open(logfile, O_WRONLY|O_CREAT|O_APPEND, 0600)) == -1) {
fprintf(stderr, "Couldn't open logfile %s: %s\n", logfile,
strerror(errno));
exit(1);
}
log_stderr_fd = fd;
}
#define MSGBUFSIZ 1024
void
set_log_handler(log_handler_fn *handler, void *ctx)
{
log_handler = handler;
log_handler_ctx = ctx;
}
void
do_log2(LogLevel level, const char *fmt,...)
{
va_list args;
va_start(args, fmt);
do_log(level, fmt, args);
va_end(args);
}
void
do_log(LogLevel level, const char *fmt, va_list args)
{
#if defined(HAVE_OPENLOG_R) && defined(SYSLOG_DATA_INIT)
struct syslog_data sdata = SYSLOG_DATA_INIT;
#endif
char msgbuf[MSGBUFSIZ];
char fmtbuf[MSGBUFSIZ];
char *txt = NULL;
int pri = LOG_INFO;
int saved_errno = errno;
log_handler_fn *tmp_handler;
if (level > log_level)
return;
switch (level) {
case SYSLOG_LEVEL_FATAL:
if (!log_on_stderr)
txt = "fatal";
pri = LOG_CRIT;
break;
case SYSLOG_LEVEL_ERROR:
if (!log_on_stderr)
txt = "error";
pri = LOG_ERR;
break;
case SYSLOG_LEVEL_INFO:
pri = LOG_INFO;
break;
case SYSLOG_LEVEL_VERBOSE:
pri = LOG_INFO;
break;
case SYSLOG_LEVEL_DEBUG1:
txt = "debug1";
pri = LOG_DEBUG;
break;
case SYSLOG_LEVEL_DEBUG2:
txt = "debug2";
pri = LOG_DEBUG;
break;
case SYSLOG_LEVEL_DEBUG3:
txt = "debug3";
pri = LOG_DEBUG;
break;
default:
txt = "internal error";
pri = LOG_ERR;
break;
}
if (txt != NULL && log_handler == NULL) {
snprintf(fmtbuf, sizeof(fmtbuf), "%s: %s", txt, fmt);
vsnprintf(msgbuf, sizeof(msgbuf), fmtbuf, args);
} else {
vsnprintf(msgbuf, sizeof(msgbuf), fmt, args);
}
strnvis(fmtbuf, msgbuf, sizeof(fmtbuf),
log_on_stderr ? LOG_STDERR_VIS : LOG_SYSLOG_VIS);
if (log_handler != NULL) {
/* Avoid recursion */
tmp_handler = log_handler;
log_handler = NULL;
tmp_handler(level, fmtbuf, log_handler_ctx);
log_handler = tmp_handler;
} else if (log_on_stderr) {
snprintf(msgbuf, sizeof msgbuf, "%.*s\r\n",
(int)sizeof msgbuf - 3, fmtbuf);
(void)write(log_stderr_fd, msgbuf, strlen(msgbuf));
} else {
#if defined(HAVE_OPENLOG_R) && defined(SYSLOG_DATA_INIT)
openlog_r(argv0 ? argv0 : __progname, LOG_PID, log_facility, &sdata);
syslog_r(pri, &sdata, "%.500s", fmtbuf);
closelog_r(&sdata);
#else
openlog(argv0 ? argv0 : __progname, LOG_PID, log_facility);
syslog(pri, "%.500s", fmtbuf);
closelog();
#endif
}
errno = saved_errno;
}