sepgsql: Enforce db_procedure:{execute} permission.

To do this, we add an additional object access hook type,
OAT_FUNCTION_EXECUTE.

KaiGai Kohei

9 files changed, 172 insertions, 19 deletions

diff --git a/contrib/sepgsql/expected/label.out b/contrib/sepgsql/expected/label.out
index 0a15f279f84..18bdf811e89 100644
--- a/contrib/sepgsql/expected/label.out
+++ b/contrib/sepgsql/expected/label.out
@@ -131,23 +131,40 @@ SELECT sepgsql_getcon();	-- confirm client privilege
  unconfined_u:unconfined_r:sepgsql_regtest_user_t:s0
 (1 row)
 
+SET sepgsql.debug_audit = true;
+SET client_min_messages = log;
 SELECT f1();			-- normal procedure
+LOG:  SELinux: allowed { execute } scontext=unconfined_u:unconfined_r:sepgsql_regtest_user_t:s0 tcontext=unconfined_u:object_r:sepgsql_proc_exec_t:s0 tclass=db_procedure name="function f1()"
+LOG:  SELinux: allowed { execute } scontext=unconfined_u:unconfined_r:sepgsql_regtest_user_t:s0 tcontext=system_u:object_r:sepgsql_proc_exec_t:s0 tclass=db_procedure name="function sepgsql_getcon()"
+CONTEXT:  SQL function "f1" statement 1
                          f1                          
 -----------------------------------------------------
  unconfined_u:unconfined_r:sepgsql_regtest_user_t:s0
 (1 row)
 
 SELECT f2();			-- trusted procedure
+LOG:  SELinux: allowed { execute } scontext=unconfined_u:unconfined_r:sepgsql_regtest_user_t:s0 tcontext=system_u:object_r:sepgsql_trusted_proc_exec_t:s0 tclass=db_procedure name="function f2()"
+LOG:  SELinux: allowed { entrypoint } scontext=unconfined_u:unconfined_r:sepgsql_regtest_user_t:s0 tcontext=system_u:object_r:sepgsql_trusted_proc_exec_t:s0 tclass=db_procedure name="function f2()"
+LOG:  SELinux: allowed { transition } scontext=unconfined_u:unconfined_r:sepgsql_regtest_user_t:s0 tcontext=unconfined_u:unconfined_r:sepgsql_trusted_proc_t:s0 tclass=process
+LOG:  SELinux: allowed { execute } scontext=unconfined_u:unconfined_r:sepgsql_trusted_proc_t:s0 tcontext=system_u:object_r:sepgsql_proc_exec_t:s0 tclass=db_procedure name="function sepgsql_getcon()"
+CONTEXT:  SQL function "f2" statement 1
                          f2                          
 -----------------------------------------------------
  unconfined_u:unconfined_r:sepgsql_trusted_proc_t:s0
 (1 row)
 
 SELECT f3();			-- trusted procedure that raises an error
+LOG:  SELinux: allowed { execute } scontext=unconfined_u:unconfined_r:sepgsql_regtest_user_t:s0 tcontext=system_u:object_r:sepgsql_trusted_proc_exec_t:s0 tclass=db_procedure name="function f3()"
+LOG:  SELinux: allowed { entrypoint } scontext=unconfined_u:unconfined_r:sepgsql_regtest_user_t:s0 tcontext=system_u:object_r:sepgsql_trusted_proc_exec_t:s0 tclass=db_procedure name="function f3()"
+LOG:  SELinux: allowed { transition } scontext=unconfined_u:unconfined_r:sepgsql_regtest_user_t:s0 tcontext=unconfined_u:unconfined_r:sepgsql_trusted_proc_t:s0 tclass=process
 ERROR:  an exception from f3()
 SELECT f4();			-- failed on domain transition
+LOG:  SELinux: allowed { execute } scontext=unconfined_u:unconfined_r:sepgsql_regtest_user_t:s0 tcontext=system_u:object_r:sepgsql_nosuch_trusted_proc_exec_t:s0 tclass=db_procedure name="function f4()"
+LOG:  SELinux: allowed { entrypoint } scontext=unconfined_u:unconfined_r:sepgsql_regtest_user_t:s0 tcontext=system_u:object_r:sepgsql_nosuch_trusted_proc_exec_t:s0 tclass=db_procedure name="function f4()"
+LOG:  SELinux: denied { transition } scontext=unconfined_u:unconfined_r:sepgsql_regtest_user_t:s0 tcontext=unconfined_u:unconfined_r:sepgsql_regtest_nosuch_t:s0 tclass=process
 ERROR:  SELinux: security policy violation
 SELECT sepgsql_getcon();	-- client's label must be restored
+LOG:  SELinux: allowed { execute } scontext=unconfined_u:unconfined_r:sepgsql_regtest_user_t:s0 tcontext=system_u:object_r:sepgsql_proc_exec_t:s0 tclass=db_procedure name="function sepgsql_getcon()"
                    sepgsql_getcon                    
 -----------------------------------------------------
  unconfined_u:unconfined_r:sepgsql_regtest_user_t:s0
diff --git a/contrib/sepgsql/expected/misc.out b/contrib/sepgsql/expected/misc.out
index 329852c5749..26d9c188c20 100644
--- a/contrib/sepgsql/expected/misc.out
+++ b/contrib/sepgsql/expected/misc.out
@@ -3,3 +3,70 @@
 --
 LOAD '$libdir/sepgsql';		-- failed
 ERROR:  SELinux: LOAD is not permitted
+--
+-- Permissions to execute functions
+--
+CREATE TABLE t1 (x int, y text);
+INSERT INTO t1 (SELECT x, md5(x::text) FROM generate_series(1,100) x);
+SET sepgsql.debug_audit = on;
+SET client_min_messages = log;
+-- regular function and operators
+SELECT * FROM t1 WHERE x > 50 AND y like '%64%';
+LOG:  SELinux: allowed { select } scontext=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:sepgsql_table_t:s0 tclass=db_table name="public.t1"
+LOG:  SELinux: allowed { select } scontext=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:sepgsql_table_t:s0 tclass=db_column name="table t1 column x"
+LOG:  SELinux: allowed { select } scontext=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:sepgsql_table_t:s0 tclass=db_column name="table t1 column y"
+LOG:  SELinux: allowed { execute } scontext=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 tcontext=system_u:object_r:sepgsql_proc_exec_t:s0 tclass=db_procedure name="function int4gt(integer,integer)"
+LOG:  SELinux: allowed { execute } scontext=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 tcontext=system_u:object_r:sepgsql_proc_exec_t:s0 tclass=db_procedure name="function textlike(text,text)"
+  x  |                y                 
+-----+----------------------------------
+  77 | 28dd2c7955ce926456240b2ff0100bde
+  89 | 7647966b7343c29048673252e490f736
+  90 | 8613985ec49eb8f757ae6439e879bb2a
+  91 | 54229abfcfa5649e7003b83dd4755294
+  99 | ac627ab1ccbdb62ec96e702f07f6425b
+ 100 | f899139df5e1059396431415e770c6dd
+(6 rows)
+
+-- aggregate function
+SELECT MIN(x), AVG(x) FROM t1;
+LOG:  SELinux: allowed { select } scontext=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:sepgsql_table_t:s0 tclass=db_table name="public.t1"
+LOG:  SELinux: allowed { select } scontext=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:sepgsql_table_t:s0 tclass=db_column name="table t1 column x"
+LOG:  SELinux: allowed { execute } scontext=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 tcontext=system_u:object_r:sepgsql_proc_exec_t:s0 tclass=db_procedure name="function avg(integer)"
+LOG:  SELinux: allowed { execute } scontext=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 tcontext=system_u:object_r:sepgsql_proc_exec_t:s0 tclass=db_procedure name="function int4_avg_accum(bigint[],integer)"
+LOG:  SELinux: allowed { execute } scontext=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 tcontext=system_u:object_r:sepgsql_proc_exec_t:s0 tclass=db_procedure name="function int8_avg(bigint[])"
+LOG:  SELinux: allowed { execute } scontext=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 tcontext=system_u:object_r:sepgsql_proc_exec_t:s0 tclass=db_procedure name="function min(integer)"
+LOG:  SELinux: allowed { execute } scontext=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 tcontext=system_u:object_r:sepgsql_proc_exec_t:s0 tclass=db_procedure name="function int4smaller(integer,integer)"
+ min |         avg         
+-----+---------------------
+   1 | 50.5000000000000000
+(1 row)
+
+-- window function
+SELECT row_number() OVER (order by x), * FROM t1 WHERE y like '%86%';
+LOG:  SELinux: allowed { select } scontext=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:sepgsql_table_t:s0 tclass=db_table name="public.t1"
+LOG:  SELinux: allowed { select } scontext=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:sepgsql_table_t:s0 tclass=db_column name="table t1 column x"
+LOG:  SELinux: allowed { select } scontext=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:sepgsql_table_t:s0 tclass=db_column name="table t1 column y"
+LOG:  SELinux: allowed { execute } scontext=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 tcontext=system_u:object_r:sepgsql_proc_exec_t:s0 tclass=db_procedure name="function row_number()"
+LOG:  SELinux: allowed { execute } scontext=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 tcontext=system_u:object_r:sepgsql_proc_exec_t:s0 tclass=db_procedure name="function textlike(text,text)"
+ row_number | x  |                y                 
+------------+----+----------------------------------
+          1 |  2 | c81e728d9d4c2f636f067f89cc14862c
+          2 | 17 | 70efdf2ec9b086079795c442636b55fb
+          3 | 22 | b6d767d2f8ed5d21a44b0e5886680cb9
+          4 | 27 | 02e74f10e0327ad868d138f2b4fdd6f0
+          5 | 33 | 182be0c5cdcd5072bb1864cdee4d3d6e
+          6 | 43 | 17e62166fc8586dfa4d1bc0e1742c08b
+          7 | 54 | a684eceee76fc522773286a895bc8436
+          8 | 73 | d2ddea18f00665ce8623e36bd4e3c7c5
+          9 | 76 | fbd7939d674997cdb4692d34de8633c4
+         10 | 89 | 7647966b7343c29048673252e490f736
+         11 | 90 | 8613985ec49eb8f757ae6439e879bb2a
+         12 | 94 | f4b9ec30ad9f68f89b29639786cb62ef
+(12 rows)
+
+RESET sepgsql.debug_audit;
+RESET client_min_messages;
+--
+-- Cleanup
+--
+DROP TABLE IF EXISTS t1 CASCADE;
diff --git a/contrib/sepgsql/hooks.c b/contrib/sepgsql/hooks.c
index 5faa1ea797f..04c5120890d 100644
--- a/contrib/sepgsql/hooks.c
+++ b/contrib/sepgsql/hooks.c
@@ -255,6 +255,13 @@ sepgsql_object_access(ObjectAccessType access,
 			}
 			break;
 
+		case OAT_FUNCTION_EXECUTE:
+			{
+				Assert(classId == ProcedureRelationId);
+				sepgsql_proc_execute(objectId);
+			}
+			break;
+
 		default:
 			elog(ERROR, "unexpected object access type: %d", (int) access);
 			break;
diff --git a/contrib/sepgsql/label.c b/contrib/sepgsql/label.c
index a5bdde34908..6146399e807 100644
--- a/contrib/sepgsql/label.c
+++ b/contrib/sepgsql/label.c
@@ -303,7 +303,8 @@ sepgsql_needs_fmgr_hook(Oid functionId)
 	object.objectSubId = 0;
 	if (!sepgsql_avc_check_perms(&object,
 								 SEPG_CLASS_DB_PROCEDURE,
-								 SEPG_DB_PROCEDURE__EXECUTE,
+								 SEPG_DB_PROCEDURE__EXECUTE |
+								 SEPG_DB_PROCEDURE__ENTRYPOINT,
 								 SEPGSQL_AVC_NOAUDIT, false))
 		return true;
 
@@ -347,13 +348,31 @@ sepgsql_fmgr_hook(FmgrHookEventType event,
 				 * process:transition permission between old and new label,
 				 * when user tries to switch security label of the client on
 				 * execution of trusted procedure.
+				 *
+				 * Also, db_procedure:entrypoint permission should be checked
+				 * whether this procedure can perform as an entrypoint of the
+				 * trusted procedure, or not.
+				 * Note that db_procedure:execute permission shall be checked
+				 * individually.
 				 */
 				if (stack->new_label)
+				{
+					ObjectAddress object;
+
+					object.classId = ProcedureRelationId;
+					object.objectId = flinfo->fn_oid;
+					object.objectSubId = 0;
+					sepgsql_avc_check_perms(&object,
+											SEPG_CLASS_DB_PROCEDURE,
+											SEPG_DB_PROCEDURE__ENTRYPOINT,
+											getObjectDescription(&object),
+											true);
+
 					sepgsql_avc_check_perms_label(stack->new_label,
 												  SEPG_CLASS_PROCESS,
 												  SEPG_PROCESS__TRANSITION,
 												  NULL, true);
-
+				}
 				*private = PointerGetDatum(stack);
 			}
 			Assert(!stack->old_label);
diff --git a/contrib/sepgsql/proc.c b/contrib/sepgsql/proc.c
index c0b0f6aeeba..fe33119118c 100644
--- a/contrib/sepgsql/proc.c
+++ b/contrib/sepgsql/proc.c
@@ -307,3 +307,29 @@ sepgsql_proc_setattr(Oid functionId)
 	systable_endscan(sscan);
 	heap_close(rel, AccessShareLock);
 }
+
+/*
+ * sepgsql_proc_execute
+ *
+ * It checks privileges to execute the supplied function
+ */
+void
+sepgsql_proc_execute(Oid functionId)
+{
+	ObjectAddress object;
+	char	   *audit_name;
+
+	/*
+	 * check db_procedure:{execute} permission
+	 */
+	object.classId = ProcedureRelationId;
+	object.objectId = functionId;
+	object.objectSubId = 0;
+	audit_name = getObjectDescription(&object);
+	sepgsql_avc_check_perms(&object,
+							SEPG_CLASS_DB_PROCEDURE,
+							SEPG_DB_PROCEDURE__EXECUTE,
+							audit_name,
+							true);
+	pfree(audit_name);
+}
diff --git a/contrib/sepgsql/sepgsql-regtest.te b/contrib/sepgsql/sepgsql-regtest.te
index 823384ecc67..8727523ca55 100644
--- a/contrib/sepgsql/sepgsql-regtest.te
+++ b/contrib/sepgsql/sepgsql-regtest.te
@@ -1,4 +1,4 @@
-policy_module(sepgsql-regtest, 1.06)
+policy_module(sepgsql-regtest, 1.07)
 
 gen_require(`
 	all_userspace_class_perms
@@ -172,25 +172,14 @@ optional_policy(`
 #
 # Rule to execute original trusted procedures
 #
-# XXX - sepgsql_client_type contains any valid client types, so we allow
-# them to execute the original trusted procedure at once.
+# These rules intends to allow any valid client types to launch trusted-
+# procedures (including ones causes domain transition to invalid domain)
+# being labeled as sepgsql_regtest_trusted_proc_exec_t and
+# sepgsql_nosuch_trusted_proc_exec_t.
 #
 optional_policy(`
 	gen_require(`
 		attribute sepgsql_client_type;
 	')
-	allow sepgsql_client_type { sepgsql_regtest_trusted_proc_exec_t sepgsql_nosuch_trusted_proc_exec_t }:db_procedure { getattr execute };
-
-	# These rules intends sepgsql_regtest_user_t domain to translate
-	# sepgsql_regtest_dba_t on execution of procedures labeled as
-	# sepgsql_regtest_trusted_proc_exec_t.
-	#
-#	allow sepgsql_client_type sepgsql_regtest_trusted_proc_exec_t:db_procedure { getattr execute };
-
-	# These rules intends sepgsql_regtest_user_t domain to translate
-	# sepgsql_regtest_nosuch_t on execution of procedures labeled as
-	# sepgsql_nosuch_trusted_proc_exec_t, without permissions to
-	# translate to sepgsql_nosuch_trusted_proc_exec_t.
-	#
-#	allow sepgsql_client_type sepgsql_nosuch_trusted_proc_exec_t:db_procedure { getattr execute install };
+	allow sepgsql_client_type { sepgsql_regtest_trusted_proc_exec_t sepgsql_nosuch_trusted_proc_exec_t }:db_procedure { getattr execute entrypoint };
 ')
diff --git a/contrib/sepgsql/sepgsql.h b/contrib/sepgsql/sepgsql.h
index 37d7455fd25..7359f1be4ad 100644
--- a/contrib/sepgsql/sepgsql.h
+++ b/contrib/sepgsql/sepgsql.h
@@ -328,5 +328,6 @@ extern void sepgsql_proc_post_create(Oid functionId);
 extern void sepgsql_proc_drop(Oid functionId);
 extern void sepgsql_proc_relabel(Oid functionId, const char *seclabel);
 extern void sepgsql_proc_setattr(Oid functionId);
+extern void sepgsql_proc_execute(Oid functionId);
 
 #endif   /* SEPGSQL_H */
diff --git a/contrib/sepgsql/sql/label.sql b/contrib/sepgsql/sql/label.sql
index 6201cd77214..7a05c248ebb 100644
--- a/contrib/sepgsql/sql/label.sql
+++ b/contrib/sepgsql/sql/label.sql
@@ -97,6 +97,8 @@ SECURITY LABEL ON COLUMN t2.b
 -- Tests for Trusted Procedures
 --
 -- @SECURITY-CONTEXT=unconfined_u:unconfined_r:sepgsql_regtest_user_t:s0
+SET sepgsql.debug_audit = true;
+SET client_min_messages = log;
 SELECT f1();			-- normal procedure
 SELECT f2();			-- trusted procedure
 SELECT f3();			-- trusted procedure that raises an error
diff --git a/contrib/sepgsql/sql/misc.sql b/contrib/sepgsql/sql/misc.sql
index a46d8a6b5c8..c2777117818 100644
--- a/contrib/sepgsql/sql/misc.sql
+++ b/contrib/sepgsql/sql/misc.sql
@@ -3,3 +3,28 @@
 --
 
 LOAD '$libdir/sepgsql';		-- failed
+
+--
+-- Permissions to execute functions
+--
+CREATE TABLE t1 (x int, y text);
+INSERT INTO t1 (SELECT x, md5(x::text) FROM generate_series(1,100) x);
+
+SET sepgsql.debug_audit = on;
+SET client_min_messages = log;
+
+-- regular function and operators
+SELECT * FROM t1 WHERE x > 50 AND y like '%64%';
+
+-- aggregate function
+SELECT MIN(x), AVG(x) FROM t1;
+
+-- window function
+SELECT row_number() OVER (order by x), * FROM t1 WHERE y like '%86%';
+
+RESET sepgsql.debug_audit;
+RESET client_min_messages;
+--
+-- Cleanup
+--
+DROP TABLE IF EXISTS t1 CASCADE;