Horton

Re: [PoC] Federated Authn/z with OAUTHBEARER

Jacob Champion <jacob.champion@enterprisedb.com>

View thread
From: Jacob Champion <jacob.champion@enterprisedb.com>
To: Daniel Gustafsson <daniel@yesql.se>
Cc: Peter Eisentraut <peter@eisentraut.org>, Antonin Houska <ah@cybertec.at>, PostgreSQL Hackers <pgsql-hackers@postgresql.org>
Date: 2025-01-09T22:35:06Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. meson: Fix install-quiet after clean

  2. oauth: Run Autoconf tests with correct compiler flags

  3. Link libpq with libdl if the platform needs that.

  4. Doc: correct spelling of meson switch.

  5. oauth: Correct SSL dependency for libpq-oauth.a

  6. oauth: Fix Autoconf build on macOS

  7. oauth: Move the builtin flow into a separate module

  8. Remove a stray "pgrminclude" annotation

  9. oauth: Simplify copy of PGoauthBearerRequest

  10. oauth: Improve validator docs on interruptibility

  11. oauth: Disallow synchronous DNS in libcurl

  12. oauth: Fix postcondition for set_timer on macOS

  13. oauth: Use IPv4-only issuer in oauth_validator tests

  14. Work around OAuth/EVFILT_TIMER quirk on NetBSD.

  15. oauth: Fix incorrect const markers in struct

  16. Add missing entry to oauth_validator test .gitignore

  17. cirrus: Temporarily fix libcurl link error

  18. Add support for OAUTHBEARER SASL mechanism

  19. libpq: Handle asynchronous actions during SASL

  20. require_auth: prepare for multiple SASL mechanisms

  21. Move PG_MAX_AUTH_TOKEN_LENGTH to libpq/auth.h

  22. Make SASL max message length configurable

  23. jsonapi: fully initialize dummy lexer

  24. common/jsonapi: support libpq as a client

  25. Remove fe_memutils from libpgcommon_shlib

  26. Revert ECPG's use of pnstrdup()

  27. Explicitly require password for SCRAM exchange

  28. Refactor SASL exchange to return tri-state status

On Thu, Jan 9, 2025 at 12:40 PM Daniel Gustafsson <daniel@yesql.se> wrote:
> + * Find the start of the .well-known prefix. IETF rules state this must be
> + * at the beginning of the path component, but OIDC defined it at the end
> + * instead, so we have to search for it anywhere.
> I was looking for a reference for OIDC defining the WK prefix placement but I
> could only find it deferring to RFC5785 like how RFC8414 does.  Can you inject
> a document reference for this?

I'll add a note in the comment. It's in Section 4 of OIDC Discovery
1.0: https://openid.net/specs/openid-connect-discovery-1_0.html#ProviderConfig

(This references RFC 5785, but only to obliquely point out that it's
not actually compliant with RFC 5785, if the issuer ID has a path
component. Section 4.1 gives an example.)

> + if (strcmp(conn->oauth_issuer_id, discovery_issuer) != 0)
> Shouldn't the scheme component really be compared case-insensitive, or has it
> been normalized at this point?  Not sure how much it matters in practice but if
> not perhaps we should add a TODO marker there?

I don't think we should. While I've read some fights about the meaning
of "identical" in OIDCD Sec 4.3, IETF seems to be pushing hard for
exact equality of issuer IDs. RFC 9207 says [1]

   This [issuer] comparison MUST use simple string comparison as
defined in Section 6.2.1 of [RFC3986].

(Simple string comparison being byte/character-wise rather than
performing a normalization step.) While RFC 9207 doesn't govern the
Device Authorization flow yet (maybe not ever?), the current OAuth 2.1
draft refers to its rules as a MUST [2], and I think we should just be
strict for the safety of future flow implementations.

I'm sure someone's going to complain at some point, but IMNSHO, the
fix for them is just to use the same formatting and capitalization as
the discovery document, and move on.

--

I'll address the other comments in the upcoming v41.

Thanks!
--Jacob

[1] https://www.rfc-editor.org/rfc/rfc9207#section-2.4
[2] https://www.ietf.org/archive/id/draft-ietf-oauth-v2-1-12.html#section-7.13.1