Files
postgresql/src/test/ssl
Michael Paquier 5fd61055ea Fix handling of SCRAM-SHA-256's channel binding with RSA-PSS certificates
OpenSSL 1.1.1 and newer versions have added support for RSA-PSS
certificates, which requires the use of a specific routine in OpenSSL to
determine which hash function to use when compiling it when using
channel binding in SCRAM-SHA-256.  X509_get_signature_nid(), that is the
original routine the channel binding code has relied on, is not able to
determine which hash algorithm to use for such certificates.  However,
X509_get_signature_info(), new to OpenSSL 1.1.1, is able to do it.  This
commit switches the channel binding logic to rely on
X509_get_signature_info() over X509_get_signature_nid(), which would be
the choice when building with 1.1.1 or newer.

The error could have been triggered on the client or the server, hence
libpq and the backend need to have their related code paths patched.
Note that attempting to load an RSA-PSS certificate with OpenSSL 1.1.0
or older leads to a failure due to an unsupported algorithm.

The discovery of relying on X509_get_signature_info() comes from Jacob,
the tests have been written by Heikki (with few tweaks from me), while I
have bundled the whole together while adding the bits needed for MSVC
and meson.

This issue exists since channel binding exists, so backpatch all the way
down.  Some tests are added in 15~, triggered if compiling with OpenSSL
1.1.1 or newer, where the certificate and key files can easily be
generated for RSA-PSS.

Reported-by: Gunnar "Nick" Bluth
Author: Jacob Champion, Heikki Linnakangas
Discussion: https://postgr.es/m/17760-b6c61e752ec07060@postgresql.org
Backpatch-through: 11
2023-02-15 10:12:31 +09:00
..
2022-01-07 19:04:57 -05:00

src/test/ssl/README

SSL regression tests
====================

This directory contains a test suite for SSL support. It tests both
client-side functionality, i.e. verifying server certificates, and
server-side functionality, i.e. certificate authorization.

CAUTION: The test server run by this test is configured to listen for
TCP connections on localhost. Any user on the same host is able to
log in to the test server while the tests are running. Do not run this
suite on a multi-user system where you don't trust all local users!

Running the tests
=================

NOTE: You must have given the --enable-tap-tests argument to configure.
Also, to use "make installcheck", you must have built and installed
contrib/sslinfo in addition to the core code.

Run
    make check
or
    make installcheck
You can use "make installcheck" if you previously did "make install".
In that case, the code in the installation tree is tested.  With
"make check", a temporary installation tree is built from the current
sources and then tested.

Either way, this test initializes, starts, and stops a test Postgres
cluster that is accessible to other local users!

See src/test/perl/README for more info about running these tests.

Certificates
============

The test suite needs a set of public/private key pairs and certificates to
run:

root_ca
	root CA, use to sign the server and client CA certificates.

server_ca
	CA used to sign server certificates.

client_ca
	CA used to sign client certificates.

server-cn-only
server-cn-and-alt-names
server-single-alt-name
server-multiple-alt-names
server-no-names
	server certificates, with small variations in the hostnames present
        in the certificate. Signed by server_ca.

server-password
	same as server-cn-only, but password-protected.

client
	a client certificate, for user "ssltestuser". Signed by client_ca.

client-revoked
	like "client", but marked as revoked in the client CA's CRL.

In addition, there are a few files that combine various certificates together
in the same file:

both-cas-1
	Contains root_ca.crt, client_ca.crt and server_ca.crt, in that order.

both-cas-2
	Contains root_ca.crt, server_ca.crt and client_ca.crt, in that order.

root+server_ca
	Contains root_crt and server_ca.crt. For use as client's "sslrootcert"
	option.

root+client_ca
	Contains root_crt and client_ca.crt. For use as server's "ssl_ca_file".

client+client_ca
	Contains client.crt and client_ca.crt in that order. For use as client's
	certificate chain.

There are also CRLs for each of the CAs: root.crl, server.crl and client.crl.

For convenience, all of these keypairs and certificates are included in the
ssl/ subdirectory. The Makefile also contains a rule, "make sslfiles", to
recreate them if you need to make changes. "make sslfiles-clean" is required
in order to recreate the full set of keypairs and certificates. To rebuild
separate files, touch (or remove) the files in question and run "make sslfiles".
This step requires at least OpenSSL 1.1.1.

TODO
====

* Allow the client-side of the tests to be run on different host easily.
  Currently, you have to manually set up the certificates for the right
  hostname, and modify the test file to skip setting up the server. And you
  have to modify the server to accept connections from the client host.

* Test having multiple server certificates, so that the private key chooses
  the certificate to present to clients. (And the same in the client-side.)