sepgsql> is a loadable module which supports label-based
mandatory access control (MAC) based on
SELinux> security
- policy. This implementation is not complete, and primarily provides
- protection for Data Manipulation Language statements (DML). Support for
- fine-grained access control of Data Definition Language (DDL) and Data
- Control Language (DCL) statements may be added in a future release.
-
- This extension won't build at all unless the installation was configured
- with --with-selinux>.
+ policy.
+
+ This implementation has signification limitations, and does not enforce
+ mandatory access control for all actions. See
+ .
+
+
+
Overview
Installation
- This module has several prerequisites.
+ This module can only be used on
Linux 2.6.28
+ or higher with
SELinux enabled. It is not
+ available on any other platform, and must be explicitly enabled using
+
--with-selinux>. You will also need libselinux>
+ 2.0.93 or higher and
selinux-policy> 3.9.13 or higher
+ (some distributions may backport the necessary rules into older policy
+ versions).
-
-
-
- v2.6.28 or later with built with SELinux enabled
-
-
-
-
-
- v2.0.93 or later
-
- This library provides a set of APIs to communicate with
-
-
-
-
-
- v3.9.13 or later
-
- The default security policy provides a set of access control rules.
- Some distributions may backport necessary rules to older policy versions.
-
-
-
-
-
-
sepgsql> needs SELinux> being
- available on the platform. You can check the current setting using
- sestatus>.
+ The sestatus> command allows you to check the status of
$ sestatus
SELinux status: enabled
- At compile time, pass the --with-selinux> option to
- the configure> script to enable this module.
-
-
-$ ./configure --enable-debug --enable-cassert --with-selinux
-$ make
-$ make install
-
-
-
- Following initdb>, add '$libdir/sepgsql'>
- to in
- the
postgresql.conf>. Note that sepgsql>
- must be loaded at server startup.
+ To use this module, you must add include sepgsql>
+ in . The module will not
+ function if loaded in any other manner. Once the module is loaded, you
+ should execute sepgsql.sql in each database.
+ This will install functions needed for security label management, and
+ assign initial security labels.
- Next, load the sepgsql.sql script for each database.
- It installs functions for security label management, and attempts to assign
- initial labels to the target objects.
-
-
- The following instruction assumes your installation is under the
- /usr/local/pgsql> directory, and the database cluster is in
- /usr/local/pgsql/data>. Adjust the paths shown below as
+ The following instructions that assume your installation is under the
+ /usr/local/pgsql> directory. Adjust the paths shown below as
appropriate for your installaton.
-$ initdb -D $PGDATA
+$ initdb
$ vi $PGDATA/postgresql.conf
$ for DBNAME in template0 template1 postgres; do
- postgres --single -F -O -c exit_on_error=true -D $PGDATA $DBNAME \
+ postgres --single -F -O -c exit_on_error=true $DBNAME \
< /usr/local/pgsql/share/contrib/sepgsql.sql > /dev/null
done
A new database object basically inherits the security label of the parent
object, except when the security policy has special rules known as
type-transition rules, in which case a different label may be applied.
- The meaning of the term "parent object" varies by object class, as follows.
+ For schemas, the parent object is the current database; for columns, it
+ is the corresponding table; for tables, sequences, views, and functions,
+ it is the containing schema.
-
-
-
- schema
-
- The parent object is the current database.
-
-
-
-
- table
-
- The parent object is the containing schema.
-
-
-
-
- column
-
- The parent object is the table.
-
-
-
-
- sequence
-
- The parent object is the containing schema.
-
-
-
-
- view
-
- The parent object is the containing schema.
-
-
-
-
- function
-
- The parent object is the containing schema.
-
-
-
-
+
DML Permissions
- This section introduces what permissions shall be checked on DML;
- SELECT>, INSERT>, UPDATE> and
- DELETE>.
-
-
- DML statements are used to reference or modify contents within
- the specified database objects; such as tables or columns.
- The access rights of the client are checked on all the objects
- mentioned in the given statement, and the kind of privileges checked
- depend on the class of the object and the type of access.
-
-
For tables, db_table:select>, db_table:insert>,
db_table:update> or db_table:delete> is
- Here are a few more corner cases.
The default database privilege system allows database superusers to
modify system catalogs using DML commands, and reference or modify
toast tables. These operations are prohibited when
Miscellaneous
- In this version, we reject the command across
- the board, because any module loaded could easily circumvent security
- policy enforcement.
+ We reject the command across the board, because
+ any module loaded could easily circumvent security policy enforcement.
+
Limitations
Author