1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ 2 #include <unistd.h> 3 #include <sys/types.h> 4 #include <stdlib.h> 5 #include <errno.h> 6 #include "selinux_internal.h" 7 #include <selinux/avc.h> 8 #include "avc_internal.h" 9 10 static pthread_once_t once = PTHREAD_ONCE_INIT; 11 static int selinux_enabled; 12 13 static void avc_init_once(void) 14 { 15 selinux_enabled = is_selinux_enabled(); 16 if (selinux_enabled == 1) 17 avc_open(NULL, 0); 18 } 19 20 int selinux_check_access(const char * scon, const char * tcon, const char *class, const char *perm, void *aux) { 21 int rc; 22 security_id_t scon_id; 23 security_id_t tcon_id; 24 security_class_t sclass; 25 access_vector_t av; 26 27 __selinux_once(once, avc_init_once); 28 29 if (selinux_enabled != 1) 30 return 0; 31 32 rc = avc_context_to_sid(scon, &scon_id); 33 if (rc < 0) 34 return rc; 35 36 rc = avc_context_to_sid(tcon, &tcon_id); 37 if (rc < 0) 38 return rc; 39 40 sclass = string_to_security_class(class); 41 if (sclass == 0) { 42 rc = errno; 43 avc_log(SELINUX_ERROR, "Unknown class %s", class); 44 if (security_deny_unknown() == 0) 45 return 0; 46 errno = rc; 47 return -1; 48 } 49 50 av = string_to_av_perm(sclass, perm); 51 if (av == 0) { 52 rc = errno; 53 avc_log(SELINUX_ERROR, "Unknown permission %s for class %s", perm, class); 54 if (security_deny_unknown() == 0) 55 return 0; 56 errno = rc; 57 return -1; 58 } 59 60 return avc_has_perm (scon_id, tcon_id, sclass, av, NULL, aux); 61 } 62 63