dsync imapc authentication mechanisms

[Timo Sirainen]

> On 05 Nov 2015, at 10:21, Randall Gellens <dovecot at randy.pensive.org> wrote:
> 
> I'm trying to use dsync to mirror mail onto a remote IMAP server. 
> The remote server is generating an error that authentication via 
> plain text is not permitted.  Does dsync imapc support any 
> non-clear-text authentication mechanisms?  The remote server supports:
> 
> AUTH=CRAM-MD5 AUTH=DIGEST-MD5 AUTH=NTLM

imapc supports SSL/TLS to avoid plaintext auth, but right now it can only support LOGIN and PLAIN mechanisms. It could support others, but somebody would just need to implement it to src/lib-sasl/. Afterwards you can use imapc_sasl_mechanisms to set the wanted SASL mechanism.