I found (by reading the Dovecot source) that the correct format is
user:example.com:password, not [email protected]::password.
I've also narrowed down the problem a bit. It seems there's a problem
using the DIGEST-MD5 mech. The {DIGEST-MD5} scheme works just fine from
a SQL database. With a {DIGEST-MD5} password the database, the PLAIN
mech works, but not the DIGEST-MD5 mech:
dovecot: auth(default): new auth connection: pid=69873
dovecot: auth(default): client in: AUTH 1 PLAIN service=smtp
nologin resp=<hidden>
dovecot: auth-worker(default): sql([email protected]): query:
SELECT password FROM mailbox WHERE username =
'[email protected]' AND active=1
dovecot: auth(default): client out: OK 1
[email protected]
dovecot: auth(default): new auth connection: pid=69884
dovecot: auth(default): client in: AUTH 1 DIGEST-MD5
service=smtp nologin
dovecot: auth(default): client out: CONT 1
cmVhbG09IiIsbm9uY2U9IktvVGpxbkNJaVEzcEMwYjVrMFY5Zmc9PSIscW9wPSJhdXRoIixjaGFyc2V0PSJ1dGYtOCIsYWxnb3JpdGhtPSJtZDUtc2VzcyI=
dovecot: auth(default): client in: CONT<hidden>
dovecot: auth-worker(default): sql([email protected]): query:
SELECT password FROM mailbox WHERE username =
'[email protected]' AND active=1
dovecot: auth(default): digest-md5([email protected]): password
mismatch
dovecot: auth(default): client out: FAIL 1
[email protected]
