This patch impacts both the QUIC frontends and listeners.
Note that "ssl-default-bind-ciphersuites", "ssl-default-bind-curves",
are not ignored by QUIC by the frontend. This is also the case for the
backends with "ssl-default-server-ciphersuites" and "ssl-default-server-curves".
These settings are set by ssl_sock_prepare_ctx() for the frontends and
by ssl_sock_prepare_srv_ssl_ctx() for the backends. But ssl_quic_initial_ctx()
first sets the default QUIC frontends (see <quic_ciphers> and <quic_groups>)
before these ssl_sock.c function are called, leading some TLS stack to
refuse them if they do not support them. This is the case for some OpenSSL 3.5
stack with FIPS support. They do not support X25519.
To fix this, set the default QUIC ciphersuites and curves only if not already
set by the settings mentioned above.
Rename <quic_ciphers> global variable to <default_quic_ciphersuites>
and <quic_groups> to <default_quic_curves> to reflect the OpenSSL API naming.
These options are taken into an account by ssl_quic_initial_ctx()
which inspects these four variable before calling SSL_CTX_set_ciphersuites()
with <default_quic_ciphersuites> as parameter and SSL_CTX_set_curves() with
<default_quic_curves> as parameter if needed, that is to say, if no ciphersuites
and curves were set by "ssl-default-bind-ciphersuites", "ssl-default-bind-curves"
as global options or "ciphersuites", "curves" as "bind" line options.
Note that the bind_conf struct is not modified when no "ciphersuites" or
"curves" option are used on "bind" lines.
On backend side, rely on ssl_sock_init_srv() to set the server ciphersuites
and curves. This function is modified to use respectively <default_quic_ciphersuites>
and <default_quic_curves> if no ciphersuites and curves were set by
"ssl-default-server-ciphersuites", "ssl-default-server-curves" as global options
or "ciphersuites", "curves" as "server" line options.
Thank to @rwagoner for having reported this issue in GH #3194 when using
an OpenSSL 3.5.4 stack with FIPS support.
Must be backported as far as 2.6