postgresql/src/include
Jacob Champion b977bd308a oauth: Allow validators to register custom HBA options
OAuth validators can already use custom GUCs to configure behavior
globally. But we currently provide no ability to adjust settings for
individual HBA entries, because the original design focused on a world
where a provider covered a "single audience" of users for one database
cluster. This assumption does not apply to multitenant use cases, where
a single validator may be controlling access for wildly different user
groups.

To improve this use case, add two new API calls for use by validator
callbacks: RegisterOAuthHBAOptions() and GetOAuthHBAOption().
Registering options "foo" and "bar" allows a user to set "validator.foo"
and "validator.bar" in an oauth HBA entry. These options are stringly
typed (syntax validation is solely the responsibility of the defining
module), and names are restricted to a subset of ASCII to avoid tying
our hands with future HBA syntax improvements.

Unfortunately, we can't check the custom option names during a reload of
the configuration, like we do with standard HBA options, without
requiring all validators to be loaded via shared_preload_libraries.
(I consider this to be a nonstarter: most validators should probably use
session_preload_libraries at most, since requiring a full restart just
to update authentication behavior will be unacceptable to many users.)
Instead, the new validator.* options are checked against the registered
list at connection time.

Multiple alternatives were proposed and/or prototyped, including
extending the GUC system to allow per-HBA overrides, joining forces with
recent refactoring work on the reloptions subsystem, and giving the
ability to customize HBA options to all PostgreSQL extensions. I
personally believe per-HBA GUC overrides are the best option, because
several existing GUCs like authentication_timeout and pre_auth_delay
would fit there usefully. But the recent addition of SNI per-host
settings in 4f433025f indicates that a more general solution is needed,
and I expect that to take multiple releases' worth of discussion.

This compromise patch, then, is intentionally designed to be an
architectural dead end: simple to describe, cheap to maintain, and
providing just enough functionality to let validators move forward for
PG19. The hope is that it will be replaced in the future by a solution
that can handle per-host, per-HBA, and other per-context configuration
with the same functionality that GUCs provide today. In the meantime,
the bulk of the code in this patch consists of strict guardrails on the
simple API, to try to ensure that we don't have any reason to regret its
existence during its unknown lifespan.

I owe particular thanks here to Zsolt Parragi, who prototyped several
approaches that guided the final design.

Suggested-by: Zsolt Parragi <zsolt.parragi@percona.com>
Suggested-by: VASUKI M <vasukianand0119@gmail.com>
Reviewed-by: Zsolt Parragi <zsolt.parragi@percona.com>
Discussion: https://postgr.es/m/CAN4CZFM3b8u5uNNNsY6XCya257u%2BDofms3su9f11iMCxvCacag%40mail.gmail.com
2026-04-07 08:15:19 -07:00
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access Allow logical replication snapshots to be database-specific 2026-04-07 12:31:18 +02:00
archive Update copyright for 2026 2026-01-01 13:24:10 -05:00
backup Update copyright for 2026 2026-01-01 13:24:10 -05:00
bootstrap Reduce header inclusions via execnodes.h 2026-03-16 14:34:57 +01:00
catalog Add pg_stat_autovacuum_scores system view. 2026-04-06 16:56:33 -05:00
commands Add CONCURRENTLY option to REPACK 2026-04-06 21:55:08 +02:00
common Remove bits* typedefs. 2026-03-30 16:12:08 -05:00
datatype Update copyright for 2026 2026-01-01 13:24:10 -05:00
executor Fix BitmapHeapScan non-parallel-aware EXPLAIN ANALYZE 2026-04-07 12:47:13 +02:00
fe_utils Harden astreamer tar parsing logic against archives it can't handle. 2026-04-02 12:20:36 -04:00
foreign Remove bits* typedefs. 2026-03-30 16:12:08 -05:00
jit jit: No backport::SectionMemoryManager for LLVM 22. 2026-04-03 14:55:11 +13:00
lib Use standard C23 and C++ attributes if available 2026-04-01 08:15:02 +02:00
libpq oauth: Allow validators to register custom HBA options 2026-04-07 08:15:19 -07:00
mb Replace pg_mblen() with bounds-checked versions. 2026-02-09 12:44:04 +13:00
nodes Mark JumbleState as a const in the post_parse_analyze hook 2026-04-07 15:22:49 +09:00
optimizer Add UPDATE/DELETE FOR PORTION OF 2026-04-01 19:06:03 +02:00
parser Mark JumbleState as a const in the post_parse_analyze hook 2026-04-07 15:22:49 +09:00
partitioning Update copyright for 2026 2026-01-01 13:24:10 -05:00
pch Update copyright for 2026 2026-01-01 13:24:10 -05:00
port Fix unportable use of __builtin_constant_p 2026-04-06 09:30:01 +07:00
portability pg_test_timing: Reduce per-loop overhead 2026-04-01 20:07:38 -04:00
postmaster Convert all remaining subsystems to use the new shmem allocation API 2026-04-06 02:13:10 +03:00
regex Update copyright for 2026 2026-01-01 13:24:10 -05:00
replication Reserve replication slots specifically for REPACK 2026-04-07 16:55:29 +02:00
rewrite Add some const qualifiers enabled by typeof_unqual change on copyObject 2026-03-19 06:35:54 +01:00
snowball Update to latest Snowball sources. 2026-01-05 15:22:37 -05:00
statistics Add support for "mcv" in pg_restore_extended_stats() 2026-01-29 12:14:08 +09:00
storage Allow logical replication snapshots to be database-specific 2026-04-07 12:31:18 +02:00
tcop SQL Property Graph Queries (SQL/PGQ) 2026-03-16 10:14:18 +01:00
tsearch Replace pg_mblen() with bounds-checked versions. 2026-02-09 12:44:04 +13:00
utils Allow autovacuum to use parallel vacuum workers. 2026-04-06 11:48:29 -07:00
.gitignore Use <stdint.h> and <inttypes.h> for c.h integers. 2024-12-04 15:05:38 +13:00
c.h Use standard C23 and C++ attributes if available 2026-04-01 08:15:02 +02:00
fmgr.h Improve type handling of varlena structures 2026-02-11 07:33:24 +09:00
funcapi.h Remove bits* typedefs. 2026-03-30 16:12:08 -05:00
getopt_long.h Update copyright for 2026 2026-01-01 13:24:10 -05:00
Makefile Fix build inconsistency due to the generation of wait-event code 2026-02-02 08:02:39 +09:00
meson.build Ensure that all three build methods install the same set of files. 2026-02-16 15:20:15 -05:00
miscadmin.h Add errdetail() with PID and UID about source of termination signal. 2026-04-07 10:22:33 -04:00
pg_config.h.in Add errdetail() with PID and UID about source of termination signal. 2026-04-07 10:22:33 -04:00
pg_config_manual.h Update copyright for 2026 2026-01-01 13:24:10 -05:00
pg_getopt.h Update copyright for 2026 2026-01-01 13:24:10 -05:00
pg_trace.h Update copyright for 2026 2026-01-01 13:24:10 -05:00
pgstat.h Convert all remaining subsystems to use the new shmem allocation API 2026-04-06 02:13:10 +03:00
pgtar.h Harden astreamer tar parsing logic against archives it can't handle. 2026-04-02 12:20:36 -04:00
pgtime.h Update copyright for 2026 2026-01-01 13:24:10 -05:00
port.h strnlen() is now required 2026-01-08 08:51:20 +01:00
postgres.h Remove Int8GetDatum function 2026-03-11 10:46:08 +01:00
postgres_ext.h Move pg_int64 back to postgres_ext.h 2025-09-16 10:48:56 +02:00
postgres_fe.h Update copyright for 2026 2026-01-01 13:24:10 -05:00
varatt.h Improve type handling of varlena structures 2026-02-11 07:33:24 +09:00
windowapi.h Update copyright for 2026 2026-01-01 13:24:10 -05:00