December 2020 - dovecot

AUTH command behaviour when authentication process failed or aborted by user is changed
by Михаил Сандаков 30 Dec '20

30 Dec '20

Hi all, I have tried to update from 2.3.10.1 to 2.3.11.3 and found some strange change of dovecot behaviour at pop3 authentication. Firstly this changes have been found by my tests with curl. But this can be simply reproduced with telnet too. On version 2.3.10.1 when authentication is failed or aborted by client, client can send "AUTH [auth method]" to retry authentication with the same or another authentication method. Example of client <-> server conversation: server <<< +OK Dovecot ready. client >>> AUTH DIGEST-MD5 server <<< [some_auth_data] client >>> * server <<< -ERR Authentication aborted by client. client >>> AUTH CRAM-MD5 server <<< [another_auth_data] But on version 2.3.11.3 in the same cases client must send only "auth method" without "AUTH". Example of successful conversation on this version: server <<< OK Dovecot ready. client >>> AUTH DIGEST-MD5 server <<< [some_auth_data] client >>> * server <<< -ERR Authentication aborted by client. client >>> CRAM-MD5 server <<< [another_auth_data] And example of what happens if a client will try to do that in an old way on version 2.3.11.3: server <<< OK Dovecot ready. client >>> AUTH DIGEST-MD5 server <<< [some_auth_data] client >>> * server <<< -ERR Authentication aborted by client. client >>> AUTH CRAM-MD5 server <<< ERR [AUTH] Unsupported authentication mechanism. As you can see dovecot tries to find an authentication method by string "AUTH" not by "CRAM-MD5". This change looks strange to me. And changes break curl, because it uses an old way to make authentication. To reproduce it with curl you can just do something like: [user(a)10.52.48.220]# curl -u [user]:[password] --verbose pop3://[dovecot-host] Also seems like new behaviour is not fully accorded to rfc1734 ( https://tools.ietf.org/html/rfc1734) Based on this part of rfc: "If an AUTH command fails with a negative response, the session remains in the AUTHORIZATION state and client may try another authentication mechanism by issuing another AUTH command, or may attempt to authenticate by using the USER/PASS or APOP commands." I think "AUTH command" means full auth command started with "AUTH", not only authentication method. But I may be wrong in the interpretation of this part. I suppose this changes was made in commit https://github.com/dovecot/core/commit/2c42881c056e5ab2e2e14b2f800d6dc72026…, but not sure about this. Seems like if authentication is aborted or failed client->current_cmd is not going to be cleaned. So I suggest to revert old behaviour in this cases. If I am right with commit, it seems like we just need to add clearing client->current_cmd if the authentication process has failed somehow.

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dovecot+ldap with keepalive
by Maciej Milaszewski 28 Dec '20

28 Dec '20

Hi I have dovecot-2.36.4 (director +5 nodes) - backend to auth is openldap+keepalived to second ldap For test i shutdown my ldap server - keepalive works perfectly VIP switched - ldapserach works ok (all connect to second ldap) but I noticed strange dovecot behavior - some user get "no response" or "waiting waiting" in dovecot i use: auth_cache_negative_ttl = 5 mins auth_cache_size = 20 M auth_cache_ttl = 5 mins service lmtp { inet_listener lmtp { address = 127.0.0.1 10.0.100.4 port = 24 } process_min_avail = 5 protocol lmtp { auth_socket_path = director-userdb mail_plugins = quota expire notify mail_log passdb { args = proxy=y nopassword=y port=24 driver = static name = } syslog_facility = local3 } in ldap server i have: idletimeout 256 Any idea ?

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Re: .imap folders
by Aki Tuomi 28 Dec '20

28 Dec '20

On 28/12/2020 13.10, Elise wrote: > Op 27-12-20 om 16:16 schreef Aki Tuomi: > >> The .imap directories contain indexes for dovecot. If you want to put >> them elsewhere, try adding :INDEX=/somewhere/else/%u to your mail >> location. > > Thanks for this. Where should I put this line or is that part of the > command line? > > /Elise > in your mail location, where you have specified `mbox:~/...` We do not recommend using mbox mail format for read-write, as the support for that is limited. Aki

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Very slow mail download/notification with dovecot 2.3.7 and Thunderbird
by ml_dovecot＠thorsten-reichelt.de 28 Dec '20

28 Dec '20

Hi! I know that there are many results if I search for "dovecot thunderbird very slow" on Google but none of them helped me with my problem. :( (I already posted this on February 2020, but forgot to answer. O.o) I am running Ubuntu 20.04 (4GB RAM, 40GB HDD with EXT4) server with the following software: - Dovecot 2.3.7.2 ---- All accounts are using Maildir ---- Sieve filters - Postfix 3.4.13 ---- with opendkim, spamassassin, razor, pyzor, .... And as IMAP client I am using Thunderbird 78.6 on Windows 10. Sieve is used to sort some incoming mails into my 228 folders (56 INBOX. folders and its subfolders (output of "find .INBOX.* -maxdepth 4 -type d -print |wc -l")). The total size of my Maildir directory is 5.5GB. My problem is that it always takes very very long to synchronize the INBOX and its subfolders. Even if there are only a few new messages to be downloaded. Sometimes Thunderbird outputs something like "downloading message 1 of 19" and it takes at least 60 seconds to download all of them. None of these mails is larger than 5kB. And sometimes it seems that the transfer is suspended for a long time and it takes >5 Minutes to synchronize only a few mails. :( And it seems that some folders are never updated in TB. In example I sort all messages from this list into a "INBOX.Mailinglists.ML-Dovecot" subfolder by using a simple sieve rule. But even after 10 minutes TB thinks that there are no new messages. As soon as I click on the ML-Dovecot folder I see in the /var/log/dovecot-info.log file that TB logs on to the server and then displays hundreds, of new messages. I checked twice but I have subscribed to all 228 folders. How can I find the bottleneck? Is there a test tool available that simulates a simple mail client and can analyse an IMAP server? This is the output of "dovecot -n": =============================== # 2.3.7.2 (3c910f64b): /etc/dovecot/dovecot.conf # Pigeonhole version 0.5.7.2 () # OS: Linux 5.4.0-54-generic x86_64 Ubuntu 20.04.1 LTS # Hostname: mail.XXXXXXX.de auth_mechanisms = plain login debug_log_path = /var/log/dovecot-debug.log default_client_limit = 15653 default_process_limit = 5200 first_valid_uid = 150 info_log_path = /var/log/dovecot-info.log last_valid_uid = 150 lda_original_recipient_header = X-Original-To log_path = /var/log/dovecot-error.log login_log_format_elements = user=<%u> method=%m rip=%r lip=%l mpid=%e %c %k mail_gid = mail mail_home = /var/vmail/%d/%n mail_location = maildir:~/Maildir mail_uid = vmail 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 namespace inbox { inbox = yes location = mailbox Archive { special_use = \Archive } 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-sql.conf.ext driver = sql } plugin { sieve = ~/.dovecot.sieve sieve_default = /var/vmail/global.sieve sieve_dir = ~/sieve } postmaster_address = thorsten(a)MY_DOMAIN.TLD protocols = " imap sieve pop3" service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0666 user = postfix } unix_listener auth-userdb { group = mail mode = 0666 user = vmail } } service imap-login { inet_listener imap { port = 143 } inet_listener imaps { port = 993 ssl = yes } process_limit = 50 process_min_avail = 2 service_count = 20 } service imap { process_limit = 1024 } service managesieve-login { inet_listener sieve { port = 4190 } service_count = 0 } ssl_cert = </etc/ssl/mail/mail.XXXXXXX.de.fullchain.pem ssl_cipher_list = ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384 ssl_dh = # hidden, use -P to show it ssl_key = # hidden, use -P to show it ssl_min_protocol = TLSv1.2 syslog_facility = local5 userdb { args = /etc/dovecot/dovecot-sql.conf.ext driver = sql } protocol lda { deliver_log_format = msgid=%m: %$ mail_plugins = " sieve" rejection_reason = Your message to <%t> was automatically rejected:%n%r } protocol imap { imap_client_workarounds = tb-extra-mailbox-sep imap_idle_notify_interval = 10 mins mail_max_userip_connections = 100 mail_plugins = } protocol sieve { info_log_path = /var/log/dovecot-sieve.log mail_max_userip_connections = 100 managesieve_implementation_string = Dovecot Pigeonhole managesieve_max_line_length = 65536 =============================== Output of "free -h": =============================== free -h total used free shared buff/cache available Mem: 3.8Gi 1.7Gi 1.1Gi 10Mi 958Mi 1.7Gi Swap: 1.0Gi 375Mi 648Mi =============================== Thank you very much! Thorsten

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.imap folders
by Elise 27 Dec '20

27 Dec '20

My user account is located at /usr/home/elise and has a subfolder ./mail In that folder I have some subfolders/subdirectories. What happens now is that dovecot creates all kind of .imap folders in these subfolders. They are all exact mirrors of the base folder(s) the .imap is part of. Can you tell me how I can prevent that dovecot creates these .imap folders other than in my home user folder /usr/home/elise and the /usr/home/elise/mail folder? /Elise

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IMAP from localhost (Squirrelmail) works, IMAP from remote (Outlook) does not authenticate
by Wayne Carrel 25 Dec '20

25 Dec '20

I have been struggling with this for some time now. I have searched, tried, broke it, fixed it, and still no luck. Will somebody please help me see what is wrong? [root@mail ~]# dovecot --version 2.2.36 (1f10bfa63) [root@mail ~]# dovecot -n # 2.2.36 (1f10bfa63): /etc/dovecot/dovecot.conf # OS: Linux 3.10.0-1160.2.2.el7.x86_64 x86_64 CentOS Linux release 7.9.2009 (Core) # Hostname: mail.mydomainname.com auth_mechanisms = plain login disable_plaintext_auth = no first_valid_uid = 1000 mail_location = maildir:~/Maildir mbox_write_locks = fcntl 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 { driver = pam } service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0666 user = postfix } unix_listener auth-userdb { group = postfix user = postfix } } service imap-login { inet_listener imap { port = 143 } inet_listener imaps { port = 993 ssl = yes } } ssl_cert = </etc/pki/dovecot/certs/dovecot.pem ssl_key = # hidden, use -P to show it userdb { driver = passwd } >From maillog: (Successful login from localhost via squirrel mail) Dec 24 16:14:19 mail dovecot: imap-login: Login: user=<terry>, method=PLAIN, rip=::1, lip=::1, mpid=2279, secured, session=<CJKj9z23kN0AAAAAAAAAAAAAAAAAAAAB> (Unsuccessful login from remote ip via Outlook) Dec 24 16:13:53 mail dovecot: imap-login: Disconnected (auth failed, 1 attempts in 4 secs): user=<terry(a)mydomainname.com>, method=PLAIN, rip=75.xx.xx.xx, lip=198.xx.xx.xx, session=<1s/i9T23yspLRsWA> I would be most grateful for any assistance anyone can provide -- my head is sore from beating against the wall! 😊

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doveadm backup -f -n inbox doing writes?
by Marc Roos 22 Dec '20

22 Dec '20

If I start a 'doveadm backup -f -n inbox' on the source server, why do also disk writes increase on the source server (indexes mostly?)

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Repeated Inbox Corruption, how to Troubleshoot?
by Bryan K. Walton 21 Dec '20

21 Dec '20

We are running Dovecot Version 2.3.8 (9df20d2db) (from the CentOS 8 repos). Twice in the last week, I've encountered an issue where my Mutt imap client logs into our imap server and has 0 new messages (when I know that there are a lot of new messages waiting on me). Both times, I've had to shut down my mail client, and then run: doveadm -Dv force-resync -u <username> INBOX After which, I reopen Mutt and all of my new emails appear in the inbox of my mail client. Running the force-resync shows no problems. Furthermore, "doveadm log errors" shows no errors on my account and there is nothing in the logs showing that anything is corrupted for me. Yet, the force-resync is fixing a problem that I can't locate. Where should I be looking (or how should I update my logging) so that I can find out the source of the problem that is causing my repeated inbox problems? Thanks! Bryan Walton -- Bryan K. Walton 319-337-3877 Linux Systems Administrator Leepfrog Technologies, Inc

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Fail2ban and login_trusted_networks
by Javi Legido 21 Dec '20

21 Dec '20

Hi there. First of all many thanks to all the people involved in this project for their time, I really appreciate it. Second my use case: a) Container running Webmail (roundcube) with dovecot-ident plugin enabled <https://github.com/roundcube/roundcubemail/issues/5336#issuecomment-2281310…> . b) Container running Dovecot 2.3.4.1 (docker-mailserver-mysql <https://github.com/Kedu-SCCL/docker-mailserver-mysql>) with fail2ban enabled Since I need to add the private IP address of the webmail to "login_trusted_networks" to "...allow to override their IP addresses and ports" I can keep login to webmail even though if the IP is blocked. Question: there's any way to: a) Allow a certain IP range to override it's IP address and ports (as in "login_trusted_networks") but b) Be blocked, as any other incoming connections, by fail2ban? More context. Once the public IP is banned (8.8.8.8 in this example): ``` 2020-12-21 10:10:31,371 fail2ban.filter [309]: INFO [dovecot] Found 8.8.8.8 - 2020-12-21 10:10:31 2020-12-21 10:10:39,189 fail2ban.filter [309]: INFO [dovecot] Found 8.8.8.8 - 2020-12-21 10:10:39 2020-12-21 10:10:51,222 fail2ban.filter [309]: INFO [dovecot] Found 8.8.8.8 - 2020-12-21 10:10:51 2020-12-21 10:10:52,008 fail2ban.actions [309]: NOTICE [dovecot] Ban 8.8.8.8 ``` I can't reach dovecot by telnet from this public IP: ``` telnet mail.example.com 143 Trying 9.9.9... telnet: Unable to connect to remote host: Connection refused ``` Unless I removed the ban: ``` docker exec mail fail2ban-client set dovecot unbanip 8.8.8.8 ``` Many thanks. Javier

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Using dovecot with RoundCubeMail - where is the information for new mail in (blue coloured) directories?
by Philip Rhoades 21 Dec '20

21 Dec '20

People, Every few years I try to work this problem out - occasionally I would like to re-mark a dir as having new mail so that the dir shows up as blue-coloured in RCM. Every time I Google in vain and then have a go at working it out myself but the only thing I can see is that there is a change in the appropriate dir dovecot.index.log file after having the blue dir clicked on (and the colour of the dir name changes back to black) - so is the information stored somewhere in RCM itself? Thanks, Phil. -- Philip Rhoades PO Box 896 Cowra NSW 2794 Australia E-mail: phil(a)pricom.com.au

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