Bug 718619

Description of problem:
libgadu in Fedora is compiled with gnutls support, but the initialization is badly implemented, resulting in being unable to handshake.

Version-Release number of selected component (if applicable):
Both 1.10.1 from main repository and 1.11.0 from updates-testing both exhibit the same problem.

How reproducible:
Open any application that uses libgadu and try to connect with SSL enabled.

Steps to Reproduce:
1. Open kadu version 0.9.2 (installed from these RPMs: http://przemal.net/pub/rpm/kadu/)
2. Ensure the "Użyj szyfrowanego połączenia" ("Use encrypted connection") checkbox is checked in account settings
3. Try to connect
  
Actual results:
An error message saying "Połączenie niemożliwe, błąd negocjacji TLS" ("Unable to connect, TLS handshake error").

Expected results:
Successful connection.

Additional info:
After few hours of debugging, I found what is probably the reason:

libgadu.c:884 (in 1.11.0):
gnutls_priority_set_direct(tmp->session, "NORMAL:-VERS-TLS", NULL);

gnutls (version 2.10.5 used in Fedora 15), during the interpretation of the string, at gnutls_priority.c:687, makes a call to gnutls_protocol_get_id() with "TLS" as the argument. gnutls_protocol_get_id (gnutls_algorithms.c:1202) performs a lookup in an array of protocol names (sup_versions at gnutls_algorithms.c:116), which does not contain "TLS". Hence, "TLS" is an incorrect value for "VERS-" construct.

The gnutls_priority_set_direct() call fails (silently, because its errors are not caught at libgadu.c:884), causing the protocol table to be left uninitialized, and then when libgadu invokes gnutls_handshake() at events.c:771, it cannot find a usable protocol (it happens at _gnutls_version_max() - gnutls_algorithms.c:1156 - called from _gnutls_send_client_hello() at gnutls_handshake.c:2003).

I don't know anything about using gnutls properly, so I won't post a patch proposal, but I'd try tweaking with the "NORMAL:-VERS-TLS" string at libgadu.c:884. I'm not sure what is the commented line at libgadu.c:885, maybe that's a working version? ;)

Anyway, thanks in advance for a fix.