Contents

• pg_set_acl
• Installation
  • Compiling
  • PostgreSQL setup
• Usage
• Example

pg_set_acl

PostgreSQL extension that implements a SET command access control list.

Installation

Compiling

This module can be built using the standard PGXS infrastructure. For this to work, the pg_config program must be available in your $PATH:

git clone https://github.com/pierreforstmann/pg_set_acl.git
cd pg_set_acl
make
make install

This extension has been validated with PostgreSQL 10, 11, 12, 13, 14 and 15.

PostgreSQL setup

Extension should be loaded at server level with shared_preload_libraries parameter: shared_preload_libraries='pg_set_acl' Extension must be created in each database with: create extension pg_set_acl;

Usage

pg_set_acl has no specific GUC setting. Note that installing pg_set_acl removes execution privilege on set_config function from PUBLIC.

pg_set_acl checks that all SET commands are in the access control list materialized by set_acl.privs table (for all users who are not superusers):

 \d set_acl.privs;
                   Table "set_acl.privs"
     Column     | Type | Collation | Nullable |   Default   
----------------+------+-----------+----------+-------------
 privilege      | text |           |          | 'SET'::text
 parameter_name | text |           | not null | 
 user_name      | text |           | not null | 

# 

If this table is empty, only superusers can use the SET command. In other words, user must have been explicitly granted privilege to use SET command with a given setting using set_acl.grant function: select set_acl.grant(setting, user); To revoke privilege to use SET command with a given setting use: select set_acl.revoke(setting, user); Only superusers can execute set_acl.grant and set_acl.revoke.

Example

testdb=# \c testdb postgres
You are now connected to database "testdb" as user "postgres".
testdb=# create extension pg_set_acl;
CREATE EXTENSION
testdb=# \c testdb testuser;
You are now connected to database "testdb" as user "testuser".
testdb=> select * from set_acl.privs;
 privilege | parameter_name | user_name 
-----------+----------------+-----------
(0 rows)

testdb=> set work_mem='1GB';
ERROR:  pg_set_acl: permission denied for (work_mem,testuser)
testdb=> \c testdb postgres
You are now connected to database "testdb" as user "postgres".
testdb=# select set_acl.grant('work_mem','testuser');
 grant 
-------
 t
(1 row)

testdb=# \c testdb testuser;
You are now connected to database "testdb" as user "testuser".
testdb=> select * from set_acl.privs;
 privilege | parameter_name | user_name 
-----------+----------------+-----------
 SET       | work_mem       | testuser
(1 row)

testdb=> set work_mem='1GB';
SET
testdb=> show work_mem;
 work_mem 
----------
 1GB
(1 row)

testdb=>