/*
 * Copyright (c) 2004 Apple Computer, Inc.
 * 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.
 * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
 *     its contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "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 APPLE OR ITS CONTRIBUTORS 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.
 *
 * $P4: //depot/projects/trustedbsd/openbsm/libbsm/bsm_control.c#13 $
 */

#include <bsm/libbsm.h>

#include <errno.h>
#include <string.h>
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>

/*
 * Parse the contents of the audit_control file to return the audit control
 * parameters.
 */
static FILE	*fp = NULL;
static char	linestr[AU_LINE_MAX];
static char	*delim = ":";

static char	inacdir = 0;
static char	ptrmoved = 0;

static pthread_mutex_t	mutex = PTHREAD_MUTEX_INITIALIZER;

/*
 * Returns the string value corresponding to the given label from the
 * configuration file.
 *
 * Must be called with mutex held.
 */
static int
getstrfromtype_locked(char *name, char **str)
{
	char *type, *nl;
	char *tokptr;
	char *last;

	*str = NULL;

	if ((fp == NULL) && ((fp = fopen(AUDIT_CONTROL_FILE, "r")) == NULL))
		return (-1); /* Error */

	while (1) {
		if (fgets(linestr, AU_LINE_MAX, fp) == NULL) {
			if (ferror(fp))
				return (-1);
			return (0);	/* EOF */
		}

		if (linestr[0] == '#')
			continue;

		/* Remove trailing new line character. */
		if ((nl = strrchr(linestr, '\n')) != NULL)
			*nl = '\0';

		tokptr = linestr;
		if ((type = strtok_r(tokptr, delim, &last)) != NULL) {
			if (strcmp(name, type) == 0) {
				/* Found matching name. */
				*str = strtok_r(NULL, delim, &last);
				if (*str == NULL) {
					errno = EINVAL;
					return (-1); /* Parse error in file */
				}
				return (0); /* Success */
			}
		}
	}
}

/*
 * Rewind the file pointer to beginning.
 */
void
setac(void)
{

	pthread_mutex_lock(&mutex);
	ptrmoved = 1;
	if (fp != NULL)
		fseek(fp, 0, SEEK_SET);
	pthread_mutex_unlock(&mutex);
}

/*
 * Close the audit_control file
 */
void
endac(void)
{

	pthread_mutex_lock(&mutex);
	ptrmoved = 1;
	if (fp != NULL) {
		fclose(fp);
		fp = NULL;
	}
	pthread_mutex_unlock(&mutex);
}

/*
 * Return audit directory information from the audit control file.
 */
int
getacdir(char *name, int len)
{
	char *dir;
	int ret = 0;

	if (name == NULL) {
		errno = EINVAL;
		return (-2);
	}

	pthread_mutex_lock(&mutex);

	/*
	 * Check if another function was called between
	 * successive calls to getacdir
	 */
	if (inacdir && ptrmoved) {
		ptrmoved = 0;
		if (fp != NULL)
			fseek(fp, 0, SEEK_SET);
		ret = 2;
	}


	if (getstrfromtype_locked(DIR_CONTROL_ENTRY, &dir) < 0) {
		pthread_mutex_unlock(&mutex);
		return (-2);
	}

	pthread_mutex_unlock(&mutex);

	if (dir == NULL)
		return (-1);

	if (strlen(dir) >= len)
		return (-3);

	strcpy(name, dir);

	return (ret);
}

/*
 * Return the minimum free diskspace value from the audit control file
 */
int
getacmin(int *min_val)
{
	char *min;

	setac();

	if (min_val == NULL) {
		errno = EINVAL;
		return (-2);
	}

	pthread_mutex_lock(&mutex);

	if (getstrfromtype_locked(MINFREE_CONTROL_ENTRY, &min) < 0) {
		pthread_mutex_unlock(&mutex);
		return (-2);
	}

	pthread_mutex_unlock(&mutex);

	if (min == NULL)
		return (1);

	*min_val = atoi(min);

	return (0);
}

/*
 * Return the system audit value from the audit contol file.
 */
int
getacflg(char *auditstr, int len)
{
	char *str;

	setac();

	if (auditstr == NULL) {
		errno = EINVAL;
		return (-2);
	}

	pthread_mutex_lock(&mutex);

	if (getstrfromtype_locked(FLAGS_CONTROL_ENTRY, &str) < 0) {
		pthread_mutex_unlock(&mutex);
		return (-2);
	}

	pthread_mutex_unlock(&mutex);

	if (str == NULL)
		return (1);

	if (strlen(str) >= len)
		return (-3);

	strcpy(auditstr, str);

	return (0);
}

/*
 * Return the non attributable flags from the audit contol file.
 */
int
getacna(char *auditstr, int len)
{
	char *str;

	setac();

	if (auditstr == NULL) {
		errno = EINVAL;
		return (-2);
	}

	pthread_mutex_lock(&mutex);

	if (getstrfromtype_locked(NA_CONTROL_ENTRY, &str) < 0) {
		pthread_mutex_unlock(&mutex);
		return (-2);
	}
	pthread_mutex_unlock(&mutex);

	if (str == NULL)
		return (1);

	if (strlen(str) >= len)
		return (-3);

	strcpy(auditstr, str);

	return (0);
}