audit_plugin.c revision f89940742f5d14dde79b69b98a414dd7b7f585c7
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright (c) 1993, 2010, Oracle and/or its affiliates. All rights reserved.
*
* private interfaces for auditd plugins and auditd.
*/
#include <bsm/audit.h>
#include <bsm/audit_record.h>
#include <bsm/audit_uevents.h>
#include <bsm/libbsm.h>
#include <errno.h>
#include <fcntl.h>
#include <libintl.h>
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/file.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <syslog.h>
#include <unistd.h>
#include <wait.h>
#include "audit_plugin.h"
static char auditwarn[] = "/etc/security/audit_warn";
static pthread_mutex_t syslog_lock;
static void
init_syslog_mutex()
{
(void) pthread_mutex_init(&syslog_lock, NULL);
}
/*
* audit_syslog() -- generate syslog messages from threads that use
* different severity, facility code, and application names.
*
* syslog(3C) is thread safe, but the set openlog() / syslog() /
* closelog() is not.
*
* Assumption: the app_name and facility code are paired, i.e.,
* if the facility code for this call is the same as for the
* the previous, the app_name hasn't changed.
*/
void
__audit_syslog(const char *app_name, int flags, int facility, int severity,
const char *message)
{
static pthread_once_t once_control = PTHREAD_ONCE_INIT;
static int logopen = 0;
static int prev_facility = -1;
(void) pthread_once(&once_control, init_syslog_mutex);
(void) pthread_mutex_lock(&syslog_lock);
if (prev_facility != facility) {
if (logopen)
closelog();
openlog(app_name, flags, facility);
syslog(severity, "%s", message);
(void) pthread_mutex_unlock(&syslog_lock);
} else {
syslog(severity, "%s", message);
(void) pthread_mutex_unlock(&syslog_lock);
}
}
/*
* __audit_dowarn - invoke the shell script auditwarn to notify the
* adminstrator about a given problem.
* parameters -
* option - what the problem is
* text - when used with options soft and hard: which file was being
* used when the filesystem filled up
* when used with the plugin option: error detail
* count - used with various options: how many times auditwarn has
* been called for this problem since it was last cleared.
*/
void
__audit_dowarn(char *option, char *text, int count)
{
pid_t pid;
int st;
char countstr[5];
char warnstring[80];
char empty[1] = "";
if ((pid = fork1()) == -1) {
__audit_syslog("auditd", LOG_PID | LOG_ODELAY | LOG_CONS,
LOG_DAEMON, LOG_ALERT, gettext("audit_warn fork failed\n"));
return;
}
if (pid != 0) {
(void) waitpid(pid, &st, 0);
return;
}
(void) snprintf(countstr, 5, "%d", count);
if (text == NULL)
text = empty;
if (strcmp(option, "soft") == 0 || strcmp(option, "hard") == 0)
(void) execl(auditwarn, auditwarn, option, text, 0);
else if (strcmp(option, "allhard") == 0)
(void) execl(auditwarn, auditwarn, option, countstr, 0);
else if (strcmp(option, "plugin") == 0)
(void) execl(auditwarn, auditwarn, option, text, countstr, 0);
else
(void) execl(auditwarn, auditwarn, option, 0);
/*
* (execl failed)
*/
if (strcmp(option, "soft") == 0)
(void) snprintf(warnstring, 80,
gettext("soft limit in %s.\n"), text);
else if (strcmp(option, "hard") == 0)
(void) snprintf(warnstring, 80,
gettext("hard limit in %s.\n"), text);
else if (strcmp(option, "allhard") == 0)
(void) sprintf(warnstring,
gettext("All audit filesystems are full.\n"));
else
(void) snprintf(warnstring, 80,
gettext("error %s.\n"), option);
__audit_syslog("auditd", LOG_PID | LOG_ODELAY | LOG_CONS, LOG_AUTH,
LOG_ALERT, (const char *)warnstring);
exit(1);
}
/*
* __audit_dowarn2 - invoke the shell script auditwarn to notify the
* adminstrator about a given problem.
* parameters -
* option - what the problem is
* name - entity reporting the problem (ie, plugin name)
* error - error string
* text - when used with options soft and hard: which file was being
* used when the filesystem filled up
* when used with the plugin option: error detail
* count - used with various options: how many times auditwarn has
* been called for this problem since it was last cleared.
*/
void
__audit_dowarn2(char *option, char *name, char *error, char *text, int count)
{
pid_t pid;
int st;
char countstr[5];
char warnstring[80];
char empty[4] = "...";
char none[3] = "--";
if ((pid = fork()) == -1) {
__audit_syslog("auditd", LOG_PID | LOG_ODELAY | LOG_CONS,
LOG_DAEMON, LOG_ALERT, gettext("audit_warn fork failed\n"));
return;
}
if (pid != 0) {
(void) waitpid(pid, &st, 0);
return;
}
(void) snprintf(countstr, 5, "%d", count);
if ((text == NULL) || (*text == '\0'))
text = empty;
if ((name == NULL) || (*name == '\0'))
name = none;
(void) execl(auditwarn, auditwarn, option, name, error, text,
countstr, 0);
/*
* (execl failed)
*/
(void) snprintf(warnstring, 80,
gettext("%s plugin error: %s\n"), name, text);
__audit_syslog("auditd", LOG_PID | LOG_ODELAY | LOG_CONS, LOG_AUTH,
LOG_ALERT, (const char *)warnstring);
exit(1);
}
/*
* logpost - post the new audit log file name.
*
* Entry name = active audit.log file name
* NULL, if checking writability (auditd),
* changing audit log files, error, or exiting (binfile).
*
* Exit 0 = success
* 1 = system error -- errno
* audit_warn called with the specific error
*
*/
int
__logpost(char *name)
{
int lerrno;
if (unlink(BINFILE_FILE) != 0 &&
errno != ENOENT) {
lerrno = errno;
__audit_dowarn("tmpfile", strerror(errno), 0);
errno = lerrno;
return (1);
}
if (name == NULL || *name == '\0') {
/* audit_binfile not active, no file pointer */
return (0);
}
if (symlink(name, BINFILE_FILE) != 0) {
lerrno = errno;
__audit_dowarn("tmpfile", strerror(errno), 0);
errno = lerrno;
return (1);
}
return (0);
}
/*
* debug use - open a file for auditd and its plugins for debug
*/
FILE *
__auditd_debug_file_open() {
static FILE *fp = NULL;
if (fp != NULL)
return (fp);
if ((fp = fopen("/var/audit/dump", "aF")) == NULL)
(void) fprintf(stderr, "failed to open debug file: %s\n",
strerror(errno));
return (fp);
}