Re: [PoC] Federated Authn/z with OAUTHBEARER

Thomas Munro <thomas.munro@gmail.com>

From: Thomas Munro <thomas.munro@gmail.com>
To: Daniel Gustafsson <daniel@yesql.se>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Jacob Champion <jacob.champion@enterprisedb.com>, Nazir Bilal Yavuz <byavuz81@gmail.com>, Andres Freund <andres@anarazel.de>, Peter Eisentraut <peter@eisentraut.org>, Antonin Houska <ah@cybertec.at>, PostgreSQL Hackers <pgsql-hackers@postgresql.org>
Date: 2025-03-19T20:11:43Z
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, Mar 20, 2025 at 2:38 AM Daniel Gustafsson <daniel@yesql.se> wrote:
> > On 19 Mar 2025, at 05:57, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> >
> > BTW, I was pretty seriously disheartened just now to realize that
> > this feature was implemented by making libpq depend on libcurl.
> > I'd misread the relevant commit messages to say that libcurl was
> > just being used as test infrastructure; but nope, it's a genuine
> > build and runtime dependency.  I wonder how much big-picture
> > thinking went into that.
>
> A considerable amount.
>
> libcurl is not a dependency for OAuth support in libpq, the support was
> designed to be exensible such that clients can hook in their own flow
> implementations.  This part does not require libcurl.  It is however a
> dependency for the RFC 8628 implementation which is included when building with
> --with-libcurl, this in order to ship something which can be used out of the
> box (for actual connections *and* testing) without clients being forced to
> provide their own implementation.
>
> This obviously means that the RFC8628 part could be moved to contrib/, but I
> fear we wouldn't make life easier for packagers by doing that.

How feasible/fragile/weird would it be to dlopen() it on demand?
Looks like it'd take ~20 function pointers:

                 U curl_easy_cleanup
                 U curl_easy_escape
                 U curl_easy_getinfo
                 U curl_easy_init
                 U curl_easy_setopt
                 U curl_easy_strerror
                 U curl_free
                 U curl_global_init
                 U curl_multi_add_handle
                 U curl_multi_cleanup
                 U curl_multi_info_read
                 U curl_multi_init
                 U curl_multi_remove_handle
                 U curl_multi_setopt
                 U curl_multi_socket_action
                 U curl_multi_socket_all
                 U curl_multi_strerror
                 U curl_slist_append
                 U curl_slist_free_all
                 U curl_version_info