September 2019 - dovecot

Dovecot proxying to some backend using LOGIN proxy_mech
by Sébastien Riccio 06 Oct '19

06 Oct '19

Hello list, I am currently testing a setup for a PoC wit this configuration. - 1 x Frontend dovecot for proxying IMAP/POP3/LMTP/ManageSieve/Submission - 2 x Backend dovecot with local mail storage The frontend does the user authentification and communicate with the backends using a master password The fronted accepts PLAIN and LOGIN auth mechanisms and talk with backends using PLAIN auth mechanism (with the master password). This works very well, it's cool. Then, I've added to this setup an existing mail server (running another mailserver software) as a 3rd backend, and would like the frontend to also proxy for this, but this time not using master password. This is working for IMAP/POP3 when it uses PLAIN auth, but not for Submission. The backend server in this case only accepts LOGIN auth and not PLAIN on port 587. So I found out there is a field in the passdb we can add (proxy_mech), and I've set it to LOGIN. The frontend seems to now use LOGIN auth mech to talk to this 3rd backend, but the authentication still fails. According to the backend logs, tt seems dovecot proxy is now using LOGIN auth, but sends garbage as username and/or password. Also IMAP that was working when using PLAIN doesn't work anymore with LOGIN. Might this be a bug or this setup shouldn't be supported at all ? Passdb MySQL table on frontend: mysql> describe users; +-------------+--------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +-------------+--------------+------+-----+---------+-------+ | user | varchar(255) | NO | PRI | NULL | | | domain | varchar(255) | NO | PRI | NULL | | | password | varchar(255) | YES | | NULL | | | displayname | varchar(255) | YES | | NULL | | | host | varchar(16) | NO | | NULL | | | usemaster | tinyint(1) | NO | | 1 | | | proxy_mech | varchar(20) | YES | | NULL | | | starttls | varchar(20) | YES | | NULL | | +-------------+--------------+------+-----+---------+-------+ mailstore-01/02 are dovecot backends otherhost is the other mailserver I also would like to proxy through dovecot proxy +---------+-----------------+-----------------------------------------+----------------+--------------+-----------+------------+----------+ | user | domain | password | displayname | host | usemaster | proxy_mech | starttls | +---------+-----------------+-----------------------------------------+----------------+--------------+-----------+------------+----------+ | user1 | somedomain.com | {SHA512-CRYPT}<some_crypted_pass> | Joe Black | mailstore-01 | 1 | NULL | NULL | | user2 | otherdomain.com | {SHA512-CRYPT}<some_crypted_pass> | Mr. Smith | mailstore-02 | 1 | NULL | NULL | | user3 | area13.com | NULL | Donald Duck | otherhost | 0 | LOGIN | any-cert | | user4 | area13.com | NULL | Thanks Obama | otherhost | 0 | LOGIN | any-cert | +---------+-----------------+-----------------------------------------+----------------+--------------+-----------+------------+----------+ Passdb query : password_query = \ SELECT concat(user, '@', domain) AS user, password, host, 'Y' AS proxy, \ IF(usemaster is TRUE, 'supermasteruserl', NULL) as master, \ IF(usemaster is TRUE, 'supermasterpassword', pass) as pass, \ IF(usemaster is FALSE, 'Y', NULL) as nopassword, \ proxy_mech, \ starttls \ FROM users WHERE user = '%n' AND domain = '%d' Some questions I'm asking myself: Is proxying using LOGIN proxy_mech supported at all to auth on backends ? Is dovecot proxying to "otherhost" supposed to decode original client auth (using PLAIN) and translate it to LOGIN format to auth with "otherhost" ? # otherhost port 587 log Without specifying proxy_mech [2019.09.19] 09:27:22.167 [192.168.60.220][3070269] cmd: EHLO dovecotproxy.local.domain [2019.09.19] 09:27:22.167 [192.168.60.220][3070269] rsp: 250-dovecotproxy.local.domain Hello [192.168.60.220]250-SIZE 52428800250-AUTH LOGIN CRAM-MD5250-STARTTLS250-8BITMIME250-DSN250 OK [2019.09.19] 09:27:22.167 [192.168.60.220][3070269] cmd: AUTH PLAIN <base64string> [2019.09.19] 09:27:22.167 [192.168.60.220][3070269] rsp: 504 Unrecognized authentication type. When using proxy_mech LOGIN [2019.09.20] 08:24:45.201 [192.168.60.220][24148464] cmd: AUTH LOGIN = [2019.09.20] 08:24:45.201 [192.168.60.220][24148464] Exception: The input is not a valid Base-64 string as it contains a non-base 64 character, more than two padding characters, or an illegal character among the padding characters. [2019.09.20] 08:24:45.201 [192.168.60.220][24148464] rsp: 535 Authentication failed # otherhost port 143 log Works without specyfing proxy_mech When using proxy_mech LOGIN (fails) [2019.09.20] 03:37:20.896 [192.168.60.220][26310645] connected at 20.09.2019 03:37:20 [2019.09.20] 03:37:20.896 [192.168.60.220][26310645] command: C CAPABILITY [2019.09.20] 03:37:20.896 [192.168.60.220][26310645] response: * CAPABILITY IMAP4rev1 AUTH=CRAM-MD5 AUTH=PLAIN UIDPLUS QUOTA XLIST CHILDREN ENABLE IDLE STARTTLS [2019.09.20] 03:37:20.896 [192.168.60.220][26310645] response: C OK CAPABILITY completed [2019.09.20] 03:37:20.896 [192.168.60.220][26310645] command: L AUTHENTICATE LOGIN [2019.09.20] 03:37:20.927 [192.168.60.220][26310645] disconnected at 20.09.2019 03:37:20 I hope I explained my setup so it's kinda understandable. I'm not good at explaining things :) Thank you for your help! root@mailfront-01:~# dovecot --version 2.3.7.2 (3c910f64b) Sébastien RICCIO SYSTEM ADMINISTRATOR

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Dovecote IMAPSieve user scripts
by Alexander Mankuta 03 Oct '19

03 Oct '19

Hello, I wonder how to configure IMAPSieve with user scripts. I can't find much information on the internet. I have Sieve and IMAPSieve for spam configured as described in the wiki and it works. Documentation mentions that imapsieve_url has to be set to appropriate ManageSieve server but no further explanation is given. What I want to achieve: let users create their own sieve scripts and execute them each time a message is being moved/copied between their mailboxes. I saw mentions of "association of user scripts with mailboxes" but I'm not sure what that means or if it's supported by Thuderbird Sieve extension (or any other software out there). Please advice. -- Regards, Alex

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lmtp and virtual users
by David Wells - Alfavinil S.A. 02 Oct '19

02 Oct '19

Good afternoon. I have dovecot setup to authenticate virtual users using either gssapi or doind a bind to an ldap server to achieve a single sign on capable imap server connected to a samba active directory DC. What I am also trying to achieve is to have dovecot's lmtp daemon handle the mails passed from postfix. However, the only way I've gotten this to work is setting allow_all_users = yes in the userdb but this causes lmtp to deliver mails to non existant accounts without rejection. I've been searching but haven't found a way to set this same thing up but having dovecots lmtp check the validity of the mails recipient against the same samba AD DC through ldap before delivering it and rejecting unknown email addresses. Could someone please provide some insight into how to achieve this? Thank you very much in advance. Best regards, David Wells.

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Migration
by Hans Brage 01 Oct '19

01 Oct '19

Hi! I'm currently running an small imap-server on Dovecot 2.2.4 but will retire that server. I've set up an new server with Dovecot 2.3.4 and will migrate the mailboxes (maildir-format) from the old to the new server. I'm planning to restructure the accounts a bit when migrating so I need to move them one by one. Its only a few so thats not a big issue. Both servers are using virtual accounts (users file). I've understood that best method for migration is to run doveadm backup -R from the new server. But I really cant figure out what other parameters or settings that I need to perform that task and if it should be run as user vmail or root. Would be greatful for any tips, hints, links or similiar. Regards, Hans

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Best way to move mail from one server to another
by James Brown 01 Oct '19

01 Oct '19

I’d like to migrate to a new server. I only need to transfer the mail store, have already done the users. I’ve seen different recommendations: IMAP-Sync Rsync Doveadmin backup and dsync What are the pros and cons of each? What would be best for me? I’m thinking that Doveadmin backup is the way to go. Both old and new servers are on same network. New server is running Dovecot 2.3.2.1, old server is 2.2.32. macOS X. Does anyone have any advice or examples? Thanks, James.

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courier to dovecot migration
by tovises 01 Oct '19

01 Oct '19

I have a quite old home server based on Debian 6.x packages using courier imap server (exim4, fetchmail, courier, apache2, squirrelmail) to keep my and my wife emails (about 25G). I want renew my server to Debian 10 (buster) and got a recommendation to use dovecot instead of courier. For this purpose I'm using a different PC as a sandbox. Debian 10 currently offer dovecot version 2.3.4.1 Installation was "peaceful" but stuck with the migration. I have choose migration using dsync, from Wiki I was choose this command: For per-user user/passwords use: doveadm -o imapc_user=foo -o pop3c_user=foo -o imapc_password=bar -o pop3c_password=bar backup -R -u user@domain imapc: (foo and bar placed real username and password) But I get error: doveadm(tovis(a)nusi.tovis-lab.mydomain.org): Error: User doesn't exist Strongly I have no real domain, I'm using "freedns". "nusi" is the local name of my old server, "tovis-lab" is conjunction with "mydomain.org" choose from freedns. I was trying short as "nusi" which is in /etc/hosts file even ip address but the same result. 143 and 943 ports are working only inside the firewall (OpenWrt). I was checked using telnet courier on the "remote" box and dovecot on the localhost. I was able to login. What should I use as "user@domain" in this situation? tovis

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Mail-crypt won't encrypt emails
by Serveria Support 30 Sep '19

30 Sep '19

Hi, We're running Dovecot 2.2.36 and we need to set up the mail-crypt plugin to encrypt all incoming and outgoing emails. Outgoing emails seem to get encrypted fine but the incoming ones don't. We tried everything including this config: mail_attribute_dict = file:%h/Maildir/dovecot-attributes mail_plugins = $mail_plugins mail_crypt plugin { mail_crypt_global_private_key = <ecprivkey.pem mail_crypt_global_public_key = <ecpubkey.pem mail_crypt_save_version = 2 } also this one: plugin { mail_crypt_curve = prime256v1 mail_crypt_save_version = 2 } but to no avail. There are no visible errors, Dovecot restarts fine and outgoing emails get encrypted. Any ideas?

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Sieve replication - does not replicate
by Daniel Botting 30 Sep '19

30 Sep '19

Hi, I have two servers replicating mail as required, the directory structure (per user), however they will not replicate the sieve scripts directory: server 1 Maildir sieve server 2 Maildir Output of doveconf -n on server 1: # 2.3.4.1 (f79e8e7e4): /etc/dovecot/dovecot.conf # Pigeonhole version 0.5.4 () doveconf: Warning: NOTE: You can get a new clean config file with: doveconf -Pn > dovecot-new.conf doveconf: Warning: Obsolete setting in /etc/dovecot/conf.d/10-ssl.conf:51: ssl_protocols has been replaced by ssl_min_protocol doveconf: Error: Could not find a minimum ssl_min_protocol setting from ssl_protocols = !SSLv2 !SSLv3: Unrecognized protocol 'SSLv2' doveconf: Warning: NOTE: You can get a new clean config file with: doveconf -Pn > dovecot-new.conf doveconf: Warning: Obsolete setting in /etc/dovecot/conf.d/10-ssl.conf:51: ssl_protocols has been replaced by ssl_min_protocol doveconf: Error: Could not find a minimum ssl_min_protocol setting from ssl_protocols = !SSLv2 !SSLv3: Unrecognized protocol 'SSLv2' # OS: Linux 4.19.0-6-amd64 x86_64 Debian 10.1 # Hostname: a_tld auth_verbose = yes default_vsz_limit = 0 doveadm_password = # hidden, use -P to show it first_valid_gid = 8 first_valid_uid = 8 last_valid_gid = 8 last_valid_uid = 8 lda_mailbox_autocreate = yes lda_mailbox_autosubscribe = yes mail_gid = 8 mail_location = maildir:~/Maildir mail_plugins = " notify replication" mail_uid = 8 managesieve_notify_capability = mailto managesieve_sieve_capability = fileinto reject envelope encoded-character vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy include variables body enotify environment mailbox date index ihave duplicate mime foreverypart extracttext editheader imapflags namespace inbox { inbox = yes location = mailbox Drafts { special_use = \Drafts } mailbox Junk { special_use = \Junk } mailbox Sent { special_use = \Sent } mailbox "Sent Messages" { special_use = \Sent } mailbox Trash { special_use = \Trash } prefix = } passdb { args = /etc/dovecot/dovecot-ldap.conf.ext driver = ldap } plugin { mail_replica = tcps:a_tld:12345 sieve = ~/.dovecot.sieve sieve_dir = ~/sieve sieve_extensions = +editheader +imapflags } protocols = " imap sieve pop3" replication_max_conns = 4 service aggregator { fifo_listener replication-notify-fifo { user = mail } unix_listener replication-notify { user = mail } } service auth { unix_listener /var/run/dovecot-exim-bridge { mode = 0660 user = Debian-exim } } service doveadm { inet_listener { port = 12345 ssl = yes } } service imap-login { inet_listener imap { port = 143 } inet_listener imaps { port = 993 ssl = yes } process_limit = 512 process_min_avail = 4 service_count = 1 } service imap { process_limit = 1024 } service managesieve-login { inet_listener sieve { port = 4190 } process_min_avail = 1 service_count = 8 vsz_limit = 256 M } service managesieve { process_limit = 1024 } service replicator { process_min_avail = 1 unix_listener replicator-doveadm { mode = 0666 } } ssl = required ssl_cert = </where/the_cert_is_installed/fullchain.pem ssl_cipher_list = ALL:!LOW:!SSLv2:!EXP:!aNULL ssl_client_ca_dir = /etc/ssl/certs ssl_key = # hidden, use -P to show it userdb { args = /etc/dovecot/dovecot-ldap.conf.ext driver = ldap override_fields = home=/var/mail/%u uid=mail gid=mail } protocol lda { mail_plugins = " notify replication sieve" } protocol imap { mail_max_userip_connections = 32 mail_plugins = " notify replication" } protocol sieve { mail_max_userip_connections = 10 managesieve_logout_format = bytes=%i/%o managesieve_max_line_length = 65536 } The only error message I can see in the logs (/var/log/mail.err) is, this is not for every user and is only occasionally: Sep 30 14:46:34 imap2 dovecot: lda(a_user)<1306><f0JXJjoHkl0aBQAAZJ7A9A>: Error: sieve: Failed to initialize script execution: Invalid postmaster_address: invalid address `postmaster@' specified for the postmaster_address setting Any suggestions would be much appreciated. Cheers -- Daniel

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Only some encrypted mailboxes
by filbar＠centrum.cz 29 Sep '19

29 Sep '19

Hello I'm looking in plugin for encrypting mailboxes. Is possible to have encrypted only some of mailboxes and other not? Thanks, Filip Bartmann

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dsync having problems with @-sign in mailbox names
by Philip Iezzi 28 Sep '19

28 Sep '19

Hi there We are running Cyrus-to-Dovecot migrations using dsync on destination Dovecot server (Debian Stretch / latest Dovecot 2.3.7.2 from community repo) like this: $ doveadm -o mail_fsync=never backup -R -u <username> imapc: For imapc configuration to connect to remote Cyrus server, see below [1]. While this works great for hundreds of mailaccounts, dsync fails with the following error on accounts with @-sign in mailbox names: dsync(<username>): Error: Failed to access mailbox INBOX/entrance/admin@example: Invalid mailbox name I can confirm, Dovecot supports @-sign in mailbox names and no client (tested with Thunderbird, Apple Mail, Roundcube webmail) has issue with this character. Also Cyrus was always supporting this. So I guess this is an issue with dsync. Can we somehow tune charset (UTF-8 ?) in imapc configuration? Thanks, Philip [1] /etc/dovecot/conf.d/90-migration.conf: ## IMAP imapc_host = imap.example.com imapc_port = 993 imapc_ssl = imaps imapc_ssl_verify = yes imapc_user = %u imapc_master_user = cyrus imapc_password = ********** imapc_features = rfc822.size fetch-headers mail_prefetch_count = 20 imapc_list_prefix = INBOX ## POP3 pop3c_host = pop3.example.com pop3c_port = 995 pop3c_ssl = pop3s pop3c_ssl_verify = yes pop3c_user = %u pop3c_master_user = cyrus pop3c_password = ********** namespace { prefix = POP3-MIGRATION-NS/ location = pop3c: list = no hidden = yes } protocol doveadm { mail_plugins = $mail_plugins pop3_migration } plugin { pop3_migration_mailbox = POP3-MIGRATION-NS/INBOX }

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