예제 #1
0
void
map_decision(security_class_t tclass, struct av_decision *avd)
{
	if (tclass < current_mapping_size) {
		bool allow_unknown = (security_deny_unknown() == 0);
		struct selinux_mapping *mapping = &current_mapping[tclass];
		unsigned int i, n = mapping->num_perms;
		access_vector_t result;

		for (i = 0, result = 0; i < n; i++) {
			if (avd->allowed & mapping->perms[i])
				result |= 1<<i;
			else if (allow_unknown && !mapping->perms[i])
				result |= 1<<i;
		}
		avd->allowed = result;

		for (i = 0, result = 0; i < n; i++) {
			if (avd->decided & mapping->perms[i])
				result |= 1<<i;
			else if (allow_unknown && !mapping->perms[i])
				result |= 1<<i;
		}
		avd->decided = result;

		for (i = 0, result = 0; i < n; i++)
			if (avd->auditallow & mapping->perms[i])
				result |= 1<<i;
		avd->auditallow = result;

		for (i = 0, result = 0; i < n; i++) {
			if (avd->auditdeny & mapping->perms[i])
				result |= 1<<i;
			else if (!allow_unknown && !mapping->perms[i])
				result |= 1<<i;
		}

		/*
		 * Make sure we audit denials for any permission check
		 * beyond the mapping->num_perms since this indicates
		 * a bug in the object manager.
		 */
		for (; i < (sizeof(result)*8); i++)
			result |= 1<<i;
		avd->auditdeny = result;
	}
}
/*
 * selinux_status_deny_unknown
 *
 * It returns a guideline to handle undefined object classes or permissions.
 * 0 means SELinux treats policy queries on undefined stuff being allowed,
 * however, 1 means such queries are denied.
 */
int selinux_status_deny_unknown(void)
{
	uint32_t	seqno;
	uint32_t	deny_unknown;

	if (selinux_status == NULL) {
		errno = EINVAL;
		return -1;
	}

	if (selinux_status == MAP_FAILED)
		return security_deny_unknown();

	/* sequence must not be changed during references */
	do {
		seqno = read_sequence(selinux_status);

		deny_unknown = selinux_status->deny_unknown;

	} while (seqno != read_sequence(selinux_status));

	return deny_unknown ? 1 : 0;
}
예제 #3
0
int main(int argc, char **argv)
{
	/* these vars are reused several times */
	int rc, opt, i, c;
	char *context, *root_path;

	/* files that need context checks */
	char *fc[MAX_CHECK];
	char *cterm = ttyname(0);
	int nfc = 0;
	struct stat m;

	/* processes that need context checks */
	char *pc[MAX_CHECK];
	int npc = 0;

	/* booleans */
	char **bools;
	int nbool;

	int verbose = 0;
	int show_bools = 0;

	/* policy */
	const char *pol_name, *root_dir;
	char *pol_path;


	while (1) {
		opt = getopt(argc, argv, "vb");
		if (opt == -1)
			break;
		switch (opt) {
		case 'v':
			verbose = 1;
			break;
		case 'b':
			show_bools = 1;
			break;
		default:
			/* invalid option */
			printf("\nUsage: %s [OPTION]\n\n", basename(argv[0]));
			printf("  -v  Verbose check of process and file contexts.\n");
			printf("  -b  Display current state of booleans.\n");
			printf("\nWithout options, show SELinux status.\n");
			return -1;
		}
	}
	printf_tab("SELinux status:");
	rc = is_selinux_enabled();

	switch (rc) {
	case 1:
		printf("enabled\n");
		break;
	case 0:
		printf("disabled\n");
		return 0;
		break;
	default:
		printf("unknown (%s)\n", strerror(errno));
		return 0;
		break;
	}

	printf_tab("SELinuxfs mount:");
	if (selinux_mnt != NULL) {
		printf("%s\n", selinux_mnt);
	} else {
		printf("not mounted\n\n");
		printf("Please mount selinuxfs for proper results.\n");
		return -1;
	}

	printf_tab("SELinux root directory:");
	root_dir = selinux_path();
	if (root_dir == NULL) {
		printf("error (%s)\n", strerror(errno));
		return -1;
	}
	/* The path has a trailing '/' so duplicate to edit */
	root_path = strdup(root_dir);
	if (!root_path) {
		printf("malloc error (%s)\n", strerror(errno));
		return -1;
	}
	/* actually blank the '/' */
	root_path[strlen(root_path) - 1] = '\0';
	printf("%s\n", root_path);
	free(root_path);

	/* Dump all the path information */
	printf_tab("Loaded policy name:");
	pol_path = strdup(selinux_policy_root());
	if (pol_path) {
		pol_name = basename(pol_path);
		puts(pol_name);
		free(pol_path);
	} else {
		printf("error (%s)\n", strerror(errno));
	}

	printf_tab("Current mode:");
	rc = security_getenforce();
	switch (rc) {
	case 1:
		printf("enforcing\n");
		break;
	case 0:
		printf("permissive\n");
		break;
	default:
		printf("unknown (%s)\n", strerror(errno));
		break;
	}

	printf_tab("Mode from config file:");
	if (selinux_getenforcemode(&rc) == 0) {
		switch (rc) {
		case 1:
			printf("enforcing\n");
			break;
		case 0:
			printf("permissive\n");
			break;
		case -1:
			printf("disabled\n");
			break;
		}
	} else {
		printf("error (%s)\n", strerror(errno));
	}

	printf_tab("Policy MLS status:");
	rc = is_selinux_mls_enabled();
	switch (rc) {
		case 0:
			printf("disabled\n");
			break;
		case 1:
			printf("enabled\n");
			break;
		default:
			printf("error (%s)\n", strerror(errno));
			break;
	}

	printf_tab("Policy deny_unknown status:");
	rc = security_deny_unknown();
	switch (rc) {
		case 0:
			printf("allowed\n");
			break;
		case 1:
			printf("denied\n");
			break;
		default:
			printf("error (%s)\n", strerror(errno));
			break;
	}

	rc = security_policyvers();
	printf_tab("Max kernel policy version:");
	if (rc < 0)
		printf("unknown (%s)\n", strerror(errno));
	else
		printf("%d\n", rc);


	if (show_bools) {
		/* show booleans */
		if (security_get_boolean_names(&bools, &nbool) >= 0) {
			printf("\nPolicy booleans:\n");

			for (i = 0; i < nbool; i++) {
				if (strlen(bools[i]) + 1 > COL)
					COL = strlen(bools[i]) + 1;
			}
			for (i = 0; i < nbool; i++) {
				printf_tab(bools[i]);

				rc = security_get_boolean_active(bools[i]);
				switch (rc) {
				case 1:
					printf("on");
					break;
				case 0:
					printf("off");
					break;
				default:
					printf("unknown (%s)", strerror(errno));
					break;
				}
				c = security_get_boolean_pending(bools[i]);
				if (c != rc)
					switch (c) {
					case 1:
						printf(" (activate pending)");
						break;
					case 0:
						printf(" (inactivate pending)");
						break;
					default:
						printf(" (pending error: %s)",
						       strerror(errno));
						break;
					}
				printf("\n");

				/* free up the booleans */
				free(bools[i]);
			}
			free(bools);
		}
	}
	/* only show contexts if -v is given */
	if (!verbose)
		return 0;

	load_checks(pc, &npc, fc, &nfc);

	printf("\nProcess contexts:\n");

	printf_tab("Current context:");
	if (getcon(&context) >= 0) {
		printf("%s\n", context);
		freecon(context);
	} else
		printf("unknown (%s)\n", strerror(errno));

	printf_tab("Init context:");
	if (getpidcon(1, &context) >= 0) {
		printf("%s\n", context);
		freecon(context);
	} else
		printf("unknown (%s)\n", strerror(errno));

	for (i = 0; i < npc; i++) {
		rc = pidof(pc[i]);
		if (rc > 0) {
			if (getpidcon(rc, &context) < 0)
				continue;

			printf_tab(pc[i]);
			printf("%s\n", context);
			freecon(context);
		}
	}

	printf("\nFile contexts:\n");

	/* controlling term */
	printf_tab("Controlling terminal:");
	if (lgetfilecon(cterm, &context) >= 0) {
		printf("%s\n", context);
		freecon(context);
	} else {
		printf("unknown (%s)\n", strerror(errno));
	}

	for (i = 0; i < nfc; i++) {
		if (lgetfilecon(fc[i], &context) >= 0) {
			printf_tab(fc[i]);

			/* check if this is a symlink */
			if (lstat(fc[i], &m)) {
				printf
				    ("%s (could not check link status (%s)!)\n",
				     context, strerror(errno));
				freecon(context);
				continue;
			}
			if (S_ISLNK(m.st_mode)) {
				/* print link target context */
				printf("%s -> ", context);
				freecon(context);

				if (getfilecon(fc[i], &context) >= 0) {
					printf("%s\n", context);
					freecon(context);
				} else {
					printf("unknown (%s)\n",
					       strerror(errno));
				}
			} else {
				printf("%s\n", context);
				freecon(context);
			}
		}
	}

	return 0;
}
예제 #4
0
파일: selinux.c 프로젝트: strk/postgres
/*
 * sepgsql_compute_avd
 *
 * It actually asks SELinux what permissions are allowed on a pair of
 * the security contexts and object class. It also returns what permissions
 * should be audited on access violation or allowed.
 * In most cases, subject's security context (scontext) is a client, and
 * target security context (tcontext) is a database object.
 *
 * The access control decision shall be set on the given av_decision.
 * The av_decision.allowed has a bitmask of SEPG_<class>__<perms>
 * to suggest a set of allowed actions in this object class.
 */
void
sepgsql_compute_avd(const char *scontext,
					const char *tcontext,
					uint16 tclass,
					struct av_decision *avd)
{
	const char		   *tclass_name;
	security_class_t	tclass_ex;
	struct av_decision	avd_ex;
	int					i, deny_unknown = security_deny_unknown();

	/* Get external code of the object class*/
	Assert(tclass < SEPG_CLASS_MAX);
	Assert(tclass == selinux_catalog[tclass].class_code);

	tclass_name = selinux_catalog[tclass].class_name;
	tclass_ex = string_to_security_class(tclass_name);

	if (tclass_ex == 0)
	{
		/*
		 * If the current security policy does not support permissions
		 * corresponding to database objects, we fill up them with dummy
		 * data.
		 * If security_deny_unknown() returns positive value, undefined
		 * permissions should be denied. Otherwise, allowed
		 */
		avd->allowed = (security_deny_unknown() > 0 ? 0 : ~0);
		avd->auditallow = 0U;
		avd->auditdeny =  ~0U;
		avd->flags = 0;

		return;
	}

	/*
	 * Ask SELinux what is allowed set of permissions on a pair of the
	 * security contexts and the given object class.
	 */
	if (security_compute_av_flags_raw((security_context_t)scontext,
									  (security_context_t)tcontext,
									  tclass_ex, 0, &avd_ex) < 0)
		ereport(ERROR,
				(errcode(ERRCODE_INTERNAL_ERROR),
				 errmsg("SELinux could not compute av_decision: "
						"scontext=%s tcontext=%s tclass=%s",
						scontext, tcontext, tclass_name)));

	/*
	 * SELinux returns its access control decision as a set of permissions
	 * represented in external code which depends on run-time environment.
	 * So, we need to translate it to the internal representation before
	 * returning results for the caller.
	 */
	memset(avd, 0, sizeof(struct av_decision));

	for (i=0; selinux_catalog[tclass].av[i].av_name; i++)
	{
		access_vector_t	av_code_ex;
		const char	   *av_name = selinux_catalog[tclass].av[i].av_name;
		uint32			av_code = selinux_catalog[tclass].av[i].av_code;

		av_code_ex = string_to_av_perm(tclass_ex, av_name);
		if (av_code_ex == 0)
		{
			/* fill up undefined permissions */
			if (!deny_unknown)
				avd->allowed |= av_code;
			avd->auditdeny |= av_code;

			continue;
		}

		if (avd_ex.allowed & av_code_ex)
			avd->allowed |= av_code;
		if (avd_ex.auditallow & av_code_ex)
			avd->auditallow |= av_code;
		if (avd_ex.auditdeny & av_code_ex)
			avd->auditdeny |= av_code;
	}

	return;
}
예제 #5
0
/* Check the permission from the caller (via getpeercon) to nscd.
   Returns 0 if access is allowed, 1 if denied, and -1 on error.

   The SELinux policy, enablement, and permission bits are all dynamic and the
   caching done by glibc is not entirely correct.  This nscd support should be
   rewritten to use selinux_check_permission.  A rewrite is risky though and
   requires some refactoring.  Currently we use symbolic mappings instead of
   compile time constants (which SELinux upstream says are going away), and we
   use security_deny_unknown to determine what to do if selinux-policy* doesn't
   have a definition for the the permission or object class we are looking
   up.  */
int
nscd_request_avc_has_perm (int fd, request_type req)
{
  /* Initialize to NULL so we know what to free in case of failure.  */
  security_context_t scon = NULL;
  security_context_t tcon = NULL;
  security_id_t ssid = NULL;
  security_id_t tsid = NULL;
  int rc = -1;
  security_class_t sc_nscd;
  access_vector_t perm;
  int avc_deny_unknown;

  /* Check if SELinux denys or allows unknown object classes
     and permissions.  It is 0 if they are allowed, 1 if they
     are not allowed and -1 on error.  */
  if ((avc_deny_unknown = security_deny_unknown ()) == -1)
    dbg_log (_("Error querying policy for undefined object classes "
	       "or permissions."));

  /* Get the security class for nscd.  If this fails we will likely be
     unable to do anything unless avc_deny_unknown is 0.  */
  sc_nscd = string_to_security_class ("nscd");
  if (sc_nscd == 0 && avc_deny_unknown == 1)
    dbg_log (_("Error getting security class for nscd."));

  /* Convert permission to AVC bits.  */
  perm = string_to_av_perm (sc_nscd, perms[req]);
  if (perm == 0 && avc_deny_unknown == 1)
      dbg_log (_("Error translating permission name "
		 "\"%s\" to access vector bit."), perms[req]);

  /* If the nscd security class was not found or perms were not
     found and AVC does not deny unknown values then allow it.  */
  if ((sc_nscd == 0 || perm == 0) && avc_deny_unknown == 0)
    return 0;

  if (getpeercon (fd, &scon) < 0)
    {
      dbg_log (_("Error getting context of socket peer"));
      goto out;
    }
  if (getcon (&tcon) < 0)
    {
      dbg_log (_("Error getting context of nscd"));
      goto out;
    }
  if (avc_context_to_sid (scon, &ssid) < 0
      || avc_context_to_sid (tcon, &tsid) < 0)
    {
      dbg_log (_("Error getting sid from context"));
      goto out;
    }

  /* The SELinux API for avc_has_perm conflates access denied and error into
     the return code -1, while nscd_request_avs_has_perm has distinct error
     (-1) and denied (1) return codes. We map the avc_has_perm access denied or
     error into an access denied at the nscd interface level (we do accurately
     report error for the getpeercon, getcon, and avc_context_to_sid interfaces
     used above).  */
  rc = avc_has_perm (ssid, tsid, sc_nscd, perm, &aeref, NULL) < 0;

out:
  if (scon)
    freecon (scon);
  if (tcon)
    freecon (tcon);
  if (ssid)
    sidput (ssid);
  if (tsid)
    sidput (tsid);

  return rc;
}
예제 #6
0
int
selinux_set_mapping(struct security_class_mapping *map)
{
	size_t size = sizeof(struct selinux_mapping);
	security_class_t i, j;
	unsigned k;
	bool print_unknown_handle = false;
	bool reject = (security_reject_unknown() == 1);
	bool deny = (security_deny_unknown() == 1);

	free(current_mapping);
	current_mapping = NULL;
	current_mapping_size = 0;

	if (avc_reset() < 0)
		goto err;

	/* Find number of classes in the input mapping */
	if (!map) {
		errno = EINVAL;
		goto err;
	}
	i = 0;
	while (map[i].name)
		i++;

	/* Allocate space for the class records, plus one for class zero */
	current_mapping = (struct selinux_mapping *)calloc(++i, size);
	if (!current_mapping)
		goto err;

	/* Store the raw class and permission values */
	j = 0;
	while (map[j].name) {
		struct security_class_mapping *p_in = map + (j++);
		struct selinux_mapping *p_out = current_mapping + j;

		p_out->value = string_to_security_class(p_in->name);
		if (!p_out->value) {
			selinux_log(SELINUX_INFO,
				    "SELinux: Class %s not defined in policy.\n",
				    p_in->name);
			if (reject)
				goto err2;
			p_out->num_perms = 0;
			print_unknown_handle = true;
			continue;
		}

		k = 0;
		while (p_in->perms[k]) {
			/* An empty permission string skips ahead */
			if (!*p_in->perms[k]) {
				k++;
				continue;
			}
			p_out->perms[k] = string_to_av_perm(p_out->value,
							    p_in->perms[k]);
			if (!p_out->perms[k]) {
				selinux_log(SELINUX_INFO,
					    "SELinux:  Permission %s in class %s not defined in policy.\n",
					    p_in->perms[k], p_in->name);
				if (reject)
					goto err2;
				print_unknown_handle = true;
			}
			k++;
		}
		p_out->num_perms = k;
	}

	if (print_unknown_handle)
		selinux_log(SELINUX_INFO,
			    "SELinux: the above unknown classes and permissions will be %s\n",
			    deny ? "denied" : "allowed");

	/* Set the mapping size here so the above lookups are "raw" */
	current_mapping_size = i;
	return 0;
err2:
	free(current_mapping);
	current_mapping = NULL;
	current_mapping_size = 0;
err:
	return -1;
}
예제 #7
0
static JSBool
rpmsx_getprop(JSContext *cx, JSObject *obj, jsid id, jsval *vp)
{
    void * ptr = JS_GetInstancePrivate(cx, obj, &rpmsxClass, NULL);
    jsint tiny = JSVAL_TO_INT(id);
#if defined(WITH_SELINUX)
    security_context_t con = NULL;
#endif

    /* XXX the class has ptr == NULL, instances have ptr != NULL. */
    if (ptr == NULL)
	return JS_TRUE;

    switch (tiny) {
    case _DEBUG:
	*vp = INT_TO_JSVAL(_debug);
	break;
#if defined(WITH_SELINUX)
    case _CURRENT:	*vp = _GET_CON(!getcon(&con));			break;
    case _PID:		*vp = _GET_CON(!getpidcon(getpid(), &con));	break;
    case _PPID:		*vp = _GET_CON(!getpidcon(getppid(), &con));	break;
    case _PREV:		*vp = _GET_CON(!getprevcon(&con));		break;
    case _EXEC:		*vp = _GET_CON(!getexeccon(&con));		break;
    case _FSCREATE:	*vp = _GET_CON(!getfscreatecon(&con));		break;
    case _KEYCREATE:	*vp = _GET_CON(!getkeycreatecon(&con));		break;
    case _SOCKCREATE:	*vp = _GET_CON(!getsockcreatecon(&con));	break;
    case _ENFORCE:	*vp = INT_TO_JSVAL(security_getenforce());	break;
    case _DENY:		*vp = INT_TO_JSVAL(security_deny_unknown());	break;
    case _POLICYVERS:	*vp = INT_TO_JSVAL(security_policyvers());	break;
    case _ENABLED:	*vp = INT_TO_JSVAL(is_selinux_enabled());	break;
    case _MLSENABLED:	*vp = INT_TO_JSVAL(is_selinux_mls_enabled());	break;
#ifdef	NOTYET
    case _BOOLS:	*vp = ;	break;
#endif
    case _ROOT:		*vp = _GET_STR(selinux_policy_root());		break;
    case _BINARY:	*vp = _GET_STR(selinux_binary_policy_path());	break;
    case _FAILSAFE:	*vp = _GET_STR(selinux_failsafe_context_path());break;
    case _REMOVABLE:	*vp = _GET_STR(selinux_removable_context_path());break;
    case _DEFAULT:	*vp = _GET_STR(selinux_default_context_path());	break;
    case _USER:		*vp = _GET_STR(selinux_user_contexts_path());	break;
    case _FCON:		*vp = _GET_STR(selinux_file_context_path());	break;
    case _FCONHOME:	*vp = _GET_STR(selinux_file_context_homedir_path());break;
    case _FCONLOCAL:	*vp = _GET_STR(selinux_file_context_local_path());break;
    case _FCONSUBS:	*vp = _GET_STR(selinux_file_context_subs_path());break;
    case _HOMEDIR:	*vp = _GET_STR(selinux_homedir_context_path());	break;
    case _MEDIA:	*vp = _GET_STR(selinux_media_context_path());	break;
    case _VIRTDOMAIN:	*vp = _GET_STR(selinux_virtual_domain_context_path());break;
    case _VIRTIMAGE:	*vp = _GET_STR(selinux_virtual_image_context_path());break;
    case _X:		*vp = _GET_STR(selinux_x_context_path());	break;
    case _CONTEXTS:	*vp = _GET_STR(selinux_contexts_path());	break;
    case _SECURETTY:	*vp = _GET_STR(selinux_securetty_types_path());	break;
    case _BOOLEANS:	*vp = _GET_STR(selinux_booleans_path());	break;
    case _CUSTOMTYPES:	*vp = _GET_STR(selinux_customizable_types_path());break;
    case _USERS:	*vp = _GET_STR(selinux_users_path());		break;
    case _USERSCONF:	*vp = _GET_STR(selinux_usersconf_path());	break;
    case _XLATIONS:	*vp = _GET_STR(selinux_translations_path());	break;
    case _COLORS:	*vp = _GET_STR(selinux_colors_path());		break;
    case _NETFILTER:	*vp = _GET_STR(selinux_netfilter_context_path());break;
    case _PATH:		*vp = _GET_STR(selinux_path());			break;
#endif
    default:
	break;
    }

#if defined(WITH_SELINUX)
    if (con) {
	freecon(con);
	con = NULL;
    }
#endif

    return JS_TRUE;
}