[Dovecot] Dovecot SASL: SCRAM-SHA-1 Authentication Fails

[Timo Sirainen]

On 26.2.2013, at 1.55, Thomas Reim <reimth at gmail.com> wrote:

> I use Dovecot SASL (2.1.15) on Ubuntu 12.04 for IMAP authentication and
> Postfix SASL authentication. I tried to setup SCRAM-SHA-1 as SASL
> mechanism. This works well on Dovecot's client side towards my OpenLDAP
> server (with libsasl-2), but fails on the server side (IMAP and SMTP).
> In the following, there's an extract from Dovecot's log, when using mutt
> as SMTP client:
> 
> dovecot: auth: scram-sha-1(?,192.168.0.65): authzid not supported

I guess mutt sets the authzid to the same as username. This is arguably a bug in mutt (or cyrus-sasl or whatever SASL library it's using?) because SCRAM-SHA1 RFC discourages doing it, but then again there's really no reason why Dovecot couldn't also support it. This should help: http://hg.dovecot.org/dovecot-2.1/rev/0af0def22533