Martin Pitt authored Apr 24, 2017 and Michael Catanzaro committed Oct 17, 2017

Up to now, a GTlsClientConnectionGnutls' session ID was built only from
the address and port. This led to overly aggressive caching of the TLS
session data and ignored the set client certificate of any subsequent
connection to the same server/port.

Move computation of the session ID from _constructed() to
_begin_handshake() when we actually need it; at that point we have the
client certificate already set. Append the certificate's hash to the
session ID to disambiguate connections with different client
certificates while still retaining the caching for multiple connections
with the same cert.

Add a second client certificate with a different modulus to the test
files and expand the connection /tls/connection/client-auth* tests to
cover this case.

Also extend /tls/connection/client-auth-failure to do a connection with
a good certificate after a failed attempt without a cert, to ensure that
our session caching doesn't attempt to re-use the failed session for
that.

https://bugzilla.gnome.org/show_bug.cgi?id=781578