[Pidgin] #5729: unable to XMPP-login by using PLAIN mechanism over unencrypted streams

[Pidgin]

#5729: unable to XMPP-login by using PLAIN mechanism over unencrypted streams
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Reporter:  calessio  |       Owner:  nwalp
    Type:  defect    |      Status:  new  
Priority:  minor     |   Component:  XMPP 
 Version:  2.4.1     |    Keywords:       
 Pending:  0         |  
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 I'm trying to use pidgin 2.4.1 to login on a server which allows PLAIN
 mechanism over unencrypted streams, but pidgin is unable to login and
 remains in the "connecting" status forever.
 I tried another XMPP client (Exodus) and it works fine.
 The difference between the two client, looking at the server-side logs, is
 that pidgin does not send the "mechanism PLAIN" SASL command, the other
 client does.

 Here is the server log generated when connecting with PIDGIN:

 ClientSession[null] packetTransferred, sent: <features
 xmlns='http://etherx.jabber.org/streams'><mechanisms
 xmlns='urn:ietf:params:xml:ns:xmpp-
 sasl'><mechanism>PLAIN</mechanism></mechanisms></features>
 ...
 ClientSession started process()
 Session[null] processing input
 Session[null] processing request
 [ClientPacketDispatcher] SASLPacket detected
 [Sasl] new packet
 [Sasl] ptype=null
 [Sasl] act = {urn:ietf:params:xml:ns:xmpp-sasl}auth
 [Sasl] data = [B at 1ac3cb6
 [Sasl] elemLst size = 0
 [Sasl] IS SASLAuthPacket
 [Sasl] mechanism
 [Sasl] action is AUTHENTICATE
 [Sasl] unsupported mechanism
 ...

 Here is the server log generated when connecting with EXODUS:

 ClientSession[null] packetTransferred, sent: <features
 xmlns='http://etherx.jabber.org/streams'><mechanisms
 xmlns='urn:ietf:params:xml:ns:xmpp-
 sasl'><mechanism>PLAIN</mechanism></mechanisms></features>
 ...
 ClientSession started process()
 Session[null] processing input
 Session[null] processing request
 [ClientPacketDispatcher] SASLPacket detected
 [Sasl] new packet
 [Sasl] ptype=null
 [Sasl] act = {urn:ietf:params:xml:ns:xmpp-sasl}auth
 [Sasl] data = [B at 187cde8
 [Sasl] elemLst size = 0
 [Sasl] IS SASLAuthPacket
 --> [Sasl] mechanism PLAIN <-- this is missing with PIDGIN!
 [Sasl] action is AUTHENTICATE
 [Sasl] PLAIN mechanism requested
 [Sasl] authzid = uid at mydomain
 [LDAP] Authenticating user uid
 ...

-- 
Ticket URL: <http://developer.pidgin.im/ticket/5729>
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