[Dovecot] Differences between IPv4 and IPv6 authentication

[Tony Meyer]

Thanks for the suggestions!

>> ~$ telnet server1.teststable.simplyspamfree.com 143
>
> Try 127.0.0.1 vs ::1

I should have thought of that :)  Indeed, ::1 works fine, so it is not
IPv6, it is external IPv6.

> Proxy/firewall/antivirus/etc in the middle?

I don't think so.

> If none of that is helpful, set auth_debug_passwords=yes and see the logs.

With the successful connection to ::1 I get:

"""
2010-11-02 02:43:29 auth(default): Info: new auth connection: pid=28423
2010-11-02 02:43:35 auth(default): Info: client in:
AUTH	1	PLAIN	service=imap	secured	lip=::1	rip=::1	lport=143	rport=42445	resp=AHRyYWluaW5nAGZsaXRrWGw3bHgyQWdQemc=
2010-11-02 02:43:35 auth-worker(default): Info: sql(training,::1):
query: SELECT DISTINCT "training" AS user, password FROM dovecot WHERE
account="testing override";
2010-11-02 02:43:35 auth-worker(default): Info: sql(training,::1):
Password mismatch
2010-11-02 02:43:35 auth-worker(default): Error:
ssha256_verify(training): SSHA256 password too short
2010-11-02 02:43:35 auth-worker(default): Warning: Invalid OTP data in passdb
2010-11-02 02:43:35 auth-worker(default): Warning: Invalid OTP data in passdb
2010-11-02 02:43:35 auth-worker(default): Info: sql(training,::1):
PLAIN-MD5(XXXXXXXX) != '6e202e30677971ea4ebe5e562ae5c195'
2010-11-02 02:43:35 auth-worker(default): Info: sql(training,::1):
query: SELECT DISTINCT "training" AS user, password FROM dovecot WHERE
account=LOWER("training");
2010-11-02 02:43:35 auth(default): Info: client out: OK	1	user=training
2010-11-02 02:43:35 auth(default): Info: master in: REQUEST	2	28374	1
2010-11-02 02:43:35 auth-worker(default): Info: sql(training,::1):
SELECT DISTINCT CONCAT_WS("/", "/var/mail", LEFT(account, 1),
LEFT(account, 2), LOWER(account)) AS home, CONCAT_WS("/",
"maildir:/var/mail", LEFT(account, 1),LEFT(account, 2),
LOWER(account)) AS mail, 1001 AS uid, 8 AS gid, CONCAT("*:storage=",
FLOOR(quota)) AS quota_rule FROM dovecot WHERE
account=LOWER("training")
2010-11-02 02:43:35 auth(default): Info: master out:
USER	2	training	home=/var/mail/t/tr/training	mail=maildir:/var/mail/t/tr/training	uid=1001	gid=8	quota_rule=*:storage=10245120
2010-11-02 02:43:35 imap-login: Info: Login: user=<training>,
method=PLAIN, rip=::1, lip=::1, secured
2010-11-02 02:43:38 IMAP(training): Info: Disconnected: Logged out bytes=8/334
"""

With the external connection to IPv6 nothing at all gets written to
the Dovecot log.  (External IPv4 works fine).  If I do an SSL
connection I get only this for external IPv6:

"""
2010-11-02 02:51:38 imap-login: Info: Disconnected (no auth attempts):
rip=178.63.10.79, lip=188.40.178.56
2010-11-02 02:51:38 auth(default): Info: new auth connection: pid=28726
"""

I'm afraid that still leaves me stumped.  Any further suggestions?

Thanks,
Tony