I'm trying to limit the ability of a read only user in postgres to only a certain view. I want to prevent them from seeing other schemas / tables / columns that they don't have permission to.
I tried this:
PostgreSQL Revoking Permissions from pg_catalog tables
This worked on my local test database but not on my AWS database because apparently AWS locks down permissions to many tables in the pg_catalog schema and if I try to revoke select on those tables I get
ERROR: permission denied for relation
Is there a way in an AWS deployed postgres (10.6) database to limit what a read only user can see?
Related
theres a default postgres user (superuser) hes able to run some random queries on all databases like select * from regions; etc.
i do have a 7 databases in pgadmin tool 1 user which is postgres and i created role service_user and granted all privileges to service_user(GRANT SELECT, INSERT, UPDATE, DELETE ON ALL TABLES IN SCHEMA public TO service_user;), but when i sign in to different database as service_user im not able to run queries, it says permission denied. so i need to login to that db as superuser grant all privileges again and then service_user is able to tun queries.
So my question is how can i grant all privileges to this service_user so he can login to any database and run queries. i can do it manually but its 7 databases i need to login and log out 7 times to every database. what if i have 500 databases running. keep in mind service_user shoould not be superuser. just read-write permissions and able to run any queries in any 7 databases. enter image description here
created a postgresql instance on AWS with the username ziggy. I restored a database to that instance. however I cannot even select any of the tables
select * FROM mac_childcare_parcels
gives me ERROR: permission denied for relation mac_childcare_parcels
********** Error **********
the owner of that table belongs to the postgres login.
so i tried running this: grant all privileges on all tables in schema public to ziggy but since I am not a superuser I cannot give myself privileges so that throws a permissions error. what do I have to do to get access to the tables?
this does not work either
grant select on mac_childcare_parcels to ziggy
this query returns successful but does not let the login ziggy access the tables
GRANT USAGE ON SCHEMA public TO ziggy;
First login with superuser and provide all rds superuser access to the newly created user using a command like below
GRANT rds_superuser TO ziggy;
replace rds_superuser with your rds superuser.
You need to also GRANT USAGE on the SCHEMA, e.g.
GRANT USAGE ON SCHEMA public TO ziggy;
The superuser access is needed to run the access level queries. But as you said that access is not present then i would say copy the replica of the db which you have restored from backup and grant yourself as superuser.
then provide all needed access to any users.
I'm new to Google Cloud SQL. I created two postgres DBs with two new users (one created from web dashboard and one created from commandline). My goal is to prevent the two users to be able to modify each other DB, but I cannot get it to work.
Here is what I want:
UserA all privileges on DB_A
UserA no privileges on DB_B
UserB all privileges on DB_B
UserB no privileges on DB_A
I already tried to grant/revoke permissions from psql prompt, but in the end I still be able to create/drop tables in DB_A as UserB.
Is it possible to achieve what I want? Am I missing something?
Postgres on Cloud SQL is standard Postgres, so it's just like any other Postgres instance:
To give a role all privileges:
GRANT ALL ON <db_name> TO <role_name>;
To remove all privileges:
REVOKE ALL ON <db_name> TO <role_name>;
The Postgres docs on privileges does give the follow caveat for:
The special privileges of an object's owner (i.e., the right to modify
or destroy the object) are always implicit in being the owner, and
cannot be granted or revoked
So keep that in mind - if UserA owns both databases, they can always modify them.
I have a master-slave configuration of PostgreSQL servers and there are multiple schemas defined in the database. Now both of master and replication servers have a user readonly which initially had only access to the public schema.
I have another schema, let's say alt_schema; and I want to give readonly user access to all it's tables.
Henceforth, I run the following query in master server to provide access of the schema to the user.
GRANT ALL ON ALL TABLES IN SCHEMA alt_schema TO readonly;
The above command successfully provided access of the schema's tables to the user.
But, the permissions are not propagated to the replication server (I waited for about 30 mins expecting there maybe some lag). Since, the automated replication failed, I tried to run the above query manually in the replication server itself, but obviously it gave me the below error:
ERROR: cannot execute GRANT in a read-only transaction
Is there way to achieve the above.
Note: My Postgres Servers are hosted in Google Cloud SQL.
I need to restrict a user, access only on a particualr schema tables only.So I tried following query and login as user1_gmail_com. But I got following error when I try to browse any schema table.
My Query:
SELECT clone_schema('my_application_template_schema','user1_gmail_com');
CREATE USER user1_gmail_com WITH PASSWORD 'myloginpassword';
REVOKE ALL ON ALL TABLES IN SCHEMA user1_gmail_com FROM PUBLIC;
GRANT SELECT ON ALL TABLES IN SCHEMA user1_gmail_com TO user1_gmail_com;
SQL error:
ERROR: permission denied for schema user1_gmail_com at character 46
In statement:
SELECT COUNT(*) AS total FROM (SELECT * FROM "user1_gmail_com"."organisations_table") AS sub
Updated Working Query:
SELECT clone_schema('my_application_template_schema','user1_gmail_com');
CREATE USER user1_gmail_com WITH PASSWORD 'myloginpassword';
REVOKE ALL ON ALL TABLES IN SCHEMA user1_gmail_com FROM PUBLIC;
GRANT USAGE ON SCHEMA user1_gmail_com TO user1_gmail_com;
GRANT SELECT ON ALL TABLES IN SCHEMA user1_gmail_com TO user1_gmail_com;
You need to grant access not only to the tables in the schema, but also to the schema itself.
From the manual:
By default, users cannot access any objects in schemas they do not own. To allow that, the owner of the schema must grant the USAGE privilege on the schema.
So either make your created user the owner of the schema, or grant USAGE on the schema to this user.
This confused me. Still not sure I'm handling it correctly. Run \h grant for the syntax within psql. Here is how I managed to get my other users and groups to work as I needed:
GRANT ALL PRIVILEGES ON SCHEMA foo TO GROUP bar;
GRANT ALL PRIVILEGES ON ALL TABLES IN SCHEMA foo TO GROUP bar;
I kept getting this error when using flyway to deploy database changes. I do some manual setup first, such as creating the database, so flyway wouldn't need those super-admin permissions.
My Fix
I had to ensure that the database user that flyway job used had ownership rights to the public schema, so that the flyway user could then assign the right to use the schema to other roles.
Additional setup Details
I am using AWS RDS (both regular and Aurora), and they don't allow super users in the databases. RDS reserves super users for use by AWS, only, so that consumers are unable to break the replication stuff that is built in. However, there's a catch-22 that you must be an owner in postgres to be able to modify it.
My solution was to create a role that acts as the owner ('owner role'), and then assign both my admin user and the flyway user to the owner role, and use ALTER scripts for each object to assign the object's owner to the owner role.
I missed the public schema, since that was auto-created when I created the database script manually. The public schema defaulted to my admin role rather than the shared owner role. So when the flyway user tried to assign public schema permissions to other roles, it didn't have the authority to do that. An error was not thrown during flyway execution, however.