NAME

       SECURITY_LABEL - define or change a security label applied to an object

SYNOPSIS

       SECURITY LABEL [ FOR provider ] ON
       {
         TABLE object_name |
         COLUMN table_name.column_name |
         AGGREGATE agg_name (agg_type [, ...] ) |
         DATABASE object_name |
         DOMAIN object_name |
         EVENT TRIGGER object_name |
         FOREIGN TABLE object_name
         FUNCTION function_name ( [ [ argmode ] [ argname ] argtype [, ...] ] ) |
         LARGE OBJECT large_object_oid |
         MATERIALIZED VIEW object_name |
         [ PROCEDURAL ] LANGUAGE object_name |
         ROLE object_name |
         SCHEMA object_name |
         SEQUENCE object_name |
         TABLESPACE object_name |
         TYPE object_name |
         VIEW object_name
       } IS 'label'

DESCRIPTION

       SECURITY LABEL applies a security label to a database object. An arbitrary number of
       security labels, one per label provider, can be associated with a given database object.
       Label providers are loadable modules which register themselves by using the function
       register_label_provider.

           Note
           register_label_provider is not an SQL function; it can only be called from C code
           loaded into the backend.

       The label provider determines whether a given label is valid and whether it is permissible
       to assign that label to a given object. The meaning of a given label is likewise at the
       discretion of the label provider.  PostgreSQL places no restrictions on whether or how a
       label provider must interpret security labels; it merely provides a mechanism for storing
       them. In practice, this facility is intended to allow integration with label-based
       mandatory access control (MAC) systems such as SE-Linux. Such systems make all access
       control decisions based on object labels, rather than traditional discretionary access
       control (DAC) concepts such as users and groups.

PARAMETERS

       object_name, table_name.column_name, agg_name, function_name
           The name of the object to be labeled. Names of tables, aggregates, domains, foreign
           tables, functions, sequences, types, and views can be schema-qualified.

       provider
           The name of the provider with which this label is to be associated. The named provider
           must be loaded and must consent to the proposed labeling operation. If exactly one
           provider is loaded, the provider name may be omitted for brevity.

       arg_type
           An input data type on which the aggregate function operates. To reference a
           zero-argument aggregate function, write * in place of the list of input data types.

       argmode
           The mode of a function argument: IN, OUT, INOUT, or VARIADIC. If omitted, the default
           is IN. Note that SECURITY LABEL ON FUNCTION does not actually pay any attention to OUT
           arguments, since only the input arguments are needed to determine the function's
           identity. So it is sufficient to list the IN, INOUT, and VARIADIC arguments.

       argname
           The name of a function argument. Note that SECURITY LABEL ON FUNCTION does not
           actually pay any attention to argument names, since only the argument data types are
           needed to determine the function's identity.

       argtype
           The data type(s) of the function's arguments (optionally schema-qualified), if any.

       large_object_oid
           The OID of the large object.

       PROCEDURAL
           This is a noise word.

       label
           The new security label, written as a string literal; or NULL to drop the security
           label.

EXAMPLES

       The following example shows how the security label of a table might be changed.

           SECURITY LABEL FOR selinux ON TABLE mytable IS 'system_u:object_r:sepgsql_table_t:s0';

COMPATIBILITY

       There is no SECURITY LABEL command in the SQL standard.

SEE ALSO

       sepgsql, dummy_seclabel