database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-07-15 19:21:59 +03:00
Code Activity

Respect permissions within logical replication.

Browse Source 
Prevent logical replication workers from performing insert, update,
delete, truncate, or copy commands on tables unless the subscription
owner has permission to do so.

Prevent subscription owners from circumventing row-level security by
forbidding replication into tables with row-level security policies
which the subscription owner is subject to, without regard to whether
the policy would ordinarily allow the INSERT, UPDATE, DELETE or
TRUNCATE which is being replicated.  This seems sufficient for now, as
superusers, roles with bypassrls, and target table owners should still
be able to replicate despite RLS policies.  We can revisit the
question of applying row-level security policies on a per-row basis if
this restriction proves too severe in practice.

Author: Mark Dilger
Reviewed-by: Jeff Davis, Andrew Dunstan, Ronan Dunklau
Discussion: https://postgr.es/m/9DFC88D3-1300-4DE8-ACBC-4CEF84399A53%40enterprisedb.com
This commit is contained in:
Jeff Davis
2022-01-07 17:38:20 -08:00
parent d0d62262d3
commit a2ab9c06ea
6 changed files with 499 additions and 8 deletions
Download Patch File Download Diff File Expand all files Collapse all files

28
src/backend/replication/logical/tablesync.c
View File

@ -111,9 +111,11 @@
#include "replication/origin.h"
#include "storage/ipc.h"
#include "storage/lmgr.h"
#include "utils/acl.h"
#include "utils/builtins.h"
#include "utils/lsyscache.h"
#include "utils/memutils.h"
#include "utils/rls.h"
#include "utils/snapmgr.h"
#include "utils/syscache.h"
@ -924,6 +926,7 @@ LogicalRepSyncTableStart(XLogRecPtr *origin_startpos)
char relstate;
XLogRecPtr relstate_lsn;
Relation rel;
AclResult aclresult;
WalRcvExecResult *res;
char originname[NAMEDATALEN];
RepOriginId originid;
@ -1042,6 +1045,31 @@ LogicalRepSyncTableStart(XLogRecPtr *origin_startpos)
*/
rel = table_open(MyLogicalRepWorker->relid, RowExclusiveLock);
/*
* Check that our table sync worker has permission to insert into the
* target table.
*/
aclresult = pg_class_aclcheck(RelationGetRelid(rel), GetUserId(),
ACL_INSERT);
if (aclresult != ACLCHECK_OK)
aclcheck_error(aclresult,
get_relkind_objtype(rel->rd_rel->relkind),
RelationGetRelationName(rel));
/*
* COPY FROM does not honor RLS policies. That is not a problem for
* subscriptions owned by roles with BYPASSRLS privilege (or superuser, who
* has it implicitly), but other roles should not be able to circumvent
* RLS. Disallow logical replication into RLS enabled relations for such
* roles.
*/
if (check_enable_rls(RelationGetRelid(rel), InvalidOid, false) == RLS_ENABLED)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("\"%s\" cannot replicate into relation with row-level security enabled: \"%s\"",
GetUserNameFromId(GetUserId(), true),
RelationGetRelationName(rel))));
/*
* Start a transaction in the remote node in REPEATABLE READ mode. This
* ensures that both the replication slot we create (see below) and the