Dovecot Proxy LTMP client connect to TCP port 0
Hi,
I am trying to set up a Dovecot proxy which proxies through POP3, IMAP and LTMP towards a different Dovecot machine.
On the proxy machine I use a MySQL database as a userdb and passwdb backend and it returns the proper information as described here: http://wiki2.dovecot.org/PasswordDatabase/ExtraFields/Proxy
IMAP and POP3 works just fine, but with LMTP I run into a problem.
On the 'proxy' machine Postfix is also running and it deliver locally to LTMP via Socket:
virtual_transport = lmtp:unix:private/dovecot-lmtp
Dovecot there is also configured to proxy LTMP:
lmtp_proxy = yes
service lmtp { unix_listener /var/spool/postfix/private/dovecot-lmtp { group = postfix mode = 0600 user = postfix } }
So far so good. A telnet to localhost 110 or 143 allows me to log in to the POP3/IMAP.
When Postfix delivers the message locally to Dovecot through LTMP it tries to proxy it though.
When doing so it tries to connect to TCP port 0 (zero).
dovecot: lmtp(22580): Error: lmtp client: connect(mbox01.XXXX.nl, 0) failed: Connection refused
I know I can return the 'port' field in the userdb query, but the same query is used for POP3, IMAP and LMTP. So that can't be hardcoded.
I fixed it for now with a CASE statement in SQL:
password_query = SELECT b.hostname AS host, NULL AS password,
'Y' AS nopassword, u.email AS destuser, 'Y' AS proxy,
CASE '%s' WHEN 'lmtp' THEN 2525 WHEN 'pop3' THEN 110 WHEN 'imap' THEN 143
END AS port
FROM User u, Backend b, Domain d
WHERE u.domainID = d.domainID
AND b.backendID = d.backendID
AND u.email = '%u'
%s is a variable containing the service Dovecot is trying to look up.
This is however rather hacky.
On my destination machine LMTP is listening on port 2525. Is there any way to tell the Dovecot LTMP client to connect to port 2525 by default?
Thanks,
Wido
I looked into the further and it seems that there is no default port for LMTP in Dovecot.
I patched the code and this seems right: https://github.com/wido/core/commit/a5917908850eb570ca441517e6bc33f6ce63ed7a
This will make the LMTP client connect to TCP port 24 if no port has been provided.
I will submitted it as a Pull Request on Github: https://github.com/dovecot/core/pull/6
Wido
Op 9 april 2016 om 11:25 schreef Wido den Hollander <wido@widodh.nl>:
Hi,
I am trying to set up a Dovecot proxy which proxies through POP3, IMAP and LTMP towards a different Dovecot machine.
On the proxy machine I use a MySQL database as a userdb and passwdb backend and it returns the proper information as described here: http://wiki2.dovecot.org/PasswordDatabase/ExtraFields/Proxy
IMAP and POP3 works just fine, but with LMTP I run into a problem.
On the 'proxy' machine Postfix is also running and it deliver locally to LTMP via Socket:
virtual_transport = lmtp:unix:private/dovecot-lmtp
Dovecot there is also configured to proxy LTMP:
lmtp_proxy = yes
service lmtp { unix_listener /var/spool/postfix/private/dovecot-lmtp { group = postfix mode = 0600 user = postfix } }
So far so good. A telnet to localhost 110 or 143 allows me to log in to the POP3/IMAP.
When Postfix delivers the message locally to Dovecot through LTMP it tries to proxy it though.
When doing so it tries to connect to TCP port 0 (zero).
dovecot: lmtp(22580): Error: lmtp client: connect(mbox01.XXXX.nl, 0) failed: Connection refused
I know I can return the 'port' field in the userdb query, but the same query is used for POP3, IMAP and LMTP. So that can't be hardcoded.
I fixed it for now with a CASE statement in SQL:
password_query = SELECT b.hostname AS host, NULL AS password,
'Y' AS nopassword, u.email AS destuser, 'Y' AS proxy,
CASE '%s' WHEN 'lmtp' THEN 2525 WHEN 'pop3' THEN 110 WHEN 'imap' THEN 143 END AS port
FROM User u, Backend b, Domain d
WHERE u.domainID = d.domainID
AND b.backendID = d.backendID
AND u.email = '%u'%s is a variable containing the service Dovecot is trying to look up.
This is however rather hacky.
On my destination machine LMTP is listening on port 2525. Is there any way to tell the Dovecot LTMP client to connect to port 2525 by default?
Thanks,
Wido
participants (1)
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Wido den Hollander