1#include <unistd.h>
2#include <sys/types.h>
3#include <stdlib.h>
4#include <errno.h>
5#include "selinux_internal.h"
6#include <selinux/avc.h>
7
8static pthread_once_t once = PTHREAD_ONCE_INIT;
9static int selinux_enabled;
10
11static void avc_init_once(void)
12{
13	selinux_enabled = is_selinux_enabled();
14	if (selinux_enabled == 1)
15		avc_open(NULL, 0);
16}
17
18int selinux_check_access(const security_context_t scon, const security_context_t tcon, const char *class, const char *perm, void *aux) {
19	int status = -1;
20	int rc = -1;
21	security_id_t scon_id;
22	security_id_t tcon_id;
23	security_class_t sclass;
24	access_vector_t av;
25
26	__selinux_once(once, avc_init_once);
27
28	if (selinux_enabled != 1)
29		return 0;
30
31	if ((rc = avc_context_to_sid(scon, &scon_id)) < 0)  return rc;
32
33	if ((rc = avc_context_to_sid(tcon, &tcon_id)) < 0)  return rc;
34
35	if ((sclass = string_to_security_class(class)) == 0) return status;
36
37	if ((av = string_to_av_perm(sclass, perm)) == 0) return status;
38
39	return avc_has_perm (scon_id, tcon_id, sclass, av, NULL, aux);
40}
41
42