February 2024 - dovecot

IRC/Matrix
by Duje 10 Feb '24

10 Feb '24

Hi there! Do you have an IRC or Matrix channel, would you consider opening one for more direct response or questions one has using dovecot? - Duje Hi there! Do you have an IRC or Matrix channel, would you consider opening one for more direct response or questions one has using dovecot? - Duje

3 2

Dovecot trusted CAs
by Felix Auringer 09 Feb '24

09 Feb '24

Hello, for our testing environment, I would like to configure a CA that is trusted by Dovecot when making TLS connections. As you can see below in the config snippets, this is for example used when proxying to itself during a login with credentials for the OIDC provider. The Dovecot documentation (https://doc.dovecot.org/configuration_manual/authentication/proxies/) states: "ssl_client_ca_dir or ssl_client_ca_file aren’t currently used for verifying the remote certificate, although ideally they will be in a future Dovecot version. For now you need to add the trusted remote certificates to ssl_ca." Configuring a trusted CA via the `ssl_ca` config option works but is a little bit weird as this option originally is for TLS client authentication. I added the CA certificate to the system trust store and removed `ssl_ca` and `ssl_client_ca_file`, but it seems that Dovecot does not use the system store. Or is there any config option I am missing? Otherwise, are there any plans when `ssl_client_ca_file` will be used for remote connections (the documentation mentions that this would ideally be fixed in a later version)? And could I then use the aggregated Debian system trust store (/etc/ssl/certs/ca-certificates.crt) there? Best regards, Felix `dovecot -n` (shortened): # 2.3.19 (b3ad6004dc): /etc/dovecot/dovecot.conf # Pigeonhole version 0.5.19 (4eae2f79) # OS: Linux 6.7.3-arch1-1 x86_64 Debian 11.8 passdb { args = /etc/dovecot/oauth2-token.conf.ext driver = oauth2 mechanisms = xoauth2 oauthbearer } passdb { args = /etc/dovecot/oauth2-password.conf.ext driver = oauth2 mechanisms = plain login } protocols = imap lmtp service imap-login { inet_listener imap { port = 0 } inet_listener imaps { port = 993 ssl = yes } } service lmtp { inet_listener { port = 24 ssl = no } } ssl = required ssl_min_protocol = TLSv1.3 ssl_prefer_server_ciphers = yes protocol lmtp { ssl_cert = </etc/dovecot/tls/lmtp-certificate-chain.pem ssl_key = # hidden, use -P to show it } protocol imap { ssl_cert = </etc/dovecot/tls/imap-certificate-chain.pem ssl_key = # hidden, use -P to show it } `oauth2-password.conf.ext`: client_id = ${DOVECOT_OIDC_CLIENT_ID} client_secret = ${DOVECOT_OIDC_CLIENT_SECRET} introspection_mode = local force_introspection = yes username_attribute = preferred_username username_format = %Lu use_grant_password = yes grant_url = ${OIDC_TOKEN_URL} scope = ${DOVECOT_OIDC_SCOPE} issuers = ${OIDC_ISSUER_URL} pass_attrs = host=dovecot port=993 ssl=yes proxy=y proxy_mech=xoauth2 pass=%{oauth2:access_token} user=%{oauth2:sub} local_validation_key_dict = fs:posix:prefix=/etc/dovecot/keys/ tls_ca_cert_file = /etc/ssl/certs/ca-certificates.crt debug = no --- Gesellschaft für interkulturelles Zusammenleben gGmbH (GIZ) Felix Auringer IT Reformationsplatz 2 13597 Berlin Tel: 030/513 0100 00; Fax: 030/513 0100 09 www.giz.berlin; felix.auringer(a)giz.berlin Amtsgericht Charlottenburg HRB 200872 B Geschäftsführerin: Dr. Britta Marschke

1 0

doveadm-backup and quota question
by Thomas Plant 09 Feb '24

09 Feb '24

Hello, I executed a backup on my dovecot installation and saw that after the first backup, the used space in quota doubled. After executing a recalc all went to normal. For this small size mailbox it is not a problem, but I did a backup on a bigger mailbox, and it started to reject messages because of 'over quota'. Here is an example: # doveadm quota get -u info(a)domain.abc Quota name Type Value Limit % User quota STORAGE 16798 16777216 0 User quota MESSAGE 628 - 0 Domain quota STORAGE 32282 67108864 0 Domain quota MESSAGE 645 - 0 [root@vmi792826 ~]# doveadm backup -u info(a)domain.abc mdbox:/tmp/backup/info@plant-systems [root@vmi792826 ~]# doveadm quota get -u info(a)domain.abc Quota name Type Value Limit % User quota STORAGE 33596 16777216 0 User quota MESSAGE 1256 - 0 Domain quota STORAGE 64563 67108864 0 Domain quota MESSAGE 1290 - 0 [root@vmi792826 ~]# doveadm quota recalc -u info(a)domain.abc [root@vmi792826 ~]# doveadm quota get -u info(a)domain.abc Quota name Type Value Limit % User quota STORAGE 16798 16777216 0 User quota MESSAGE 628 - 0 Domain quota STORAGE 32282 67108864 0 Domain quota MESSAGE 645 - 0 Is it normal to have to issue a recalc after backup, or can it be some misconfiguration on my side? Hello, I executed a backup on my dovecot installation and saw that after the first backup, the used space in quota doubled. After executing a recalc all went to normal. For this small size mailbox it is not a problem, but I did a backup on a bigger mailbox, and it started to reject messages because of 'over quota'. Here is an example: # doveadm quota get -u info(a)domain.abc Quota name Type Value Limit % User quota STORAGE 16798 16777216 0 User quota MESSAGE 628 - 0 Domain quota STORAGE 32282 67108864 0 Domain quota MESSAGE 645 - 0 [root@vmi792826 ~]# doveadm backup -u info(a)domain.abc mdbox:/tmp/backup/ info@plant-systems [root@vmi792826 ~]# doveadm quota get -u info(a)domain.abc Quota name Type Value Limit % User quota STORAGE 33596 16777216 0 User quota MESSAGE 1256 - 0 Domain quota STORAGE 64563 67108864 0 Domain quota MESSAGE 1290 - 0 [root@vmi792826 ~]# doveadm quota recalc -u info(a)domain.abc [root@vmi792826 ~]# doveadm quota get -u info(a)domain.abc Quota name Type Value Limit % User quota STORAGE 16798 16777216 0 User quota MESSAGE 628 - 0 Domain quota STORAGE 32282 67108864 0 Domain quota MESSAGE 645 - 0 Is it normal to have to issue a recalc after backup, or can it be some misconfiguration on my side?

1 0

Re: Auth USER lookup failed
by Michael Slusarz 08 Feb '24

08 Feb '24

> On 02/05/2024 10:17 PM MST thecoudge(a)gmail.com wrote: > > I have dovecot working with PAM and Samba DC authentication for IMAP. However when I'm attempting to pass emails from postfix via LMTP > I don't actually need to authenticate LMTP I'm happy to check for valid users upstream. > > I'm getting the error: > Feb 06 15:11:39 Debian-server postfix/local[178200]: ADF0E78713C: passing <dom.username(a)Debian-server.sr.local> to transport=lmtp > Feb 06 15:11:39 Debian-server dovecot[178075]: auth: Error: static(dom.username): passdb doesn't support lookups, can't verify user's existence > Feb 06 15:11:39 Debian-server dovecot[178075]: lmtp(dom.username(a)Debian-server.sr.local)<178233><GJ/9Nou/wWU5uAIAiShiCA:T2>: Error: auth-master: userdb lookup(dom.username(a)Debian-server.sr.local): Auth USER lookup failed You need to define a userdb to return user information. Since LMTP doesn't require auth, it can't use the passdb so that's what the error message is saying. michael

3 2

Permission problem when using sieve script
by tacodewolff＠gmail.com 07 Feb '24

07 Feb '24

Hi, I've been banging my head on this problem for a while now and need some help on this issue. I've set up Dovecot with Sieve scripts, which use bash scripts to either learn ham or learn spam. This is sent to the Rspamd controller (using a Unix socket at /var/run/rspamd/rspamd-controller.sock). The socket has permissions 660 and is owned by _rspamd:_rspamd. It's directory and parent directory have 755. The sieve script looks like: exec /usr/bin/rspamc -h /var/run/rspamd/rspamd-controller.sock -P 'password' learn_ham I've added the dovecot user to the _rspamd group, but I consistently get "Permission denied" when marking emails as ham/spam. Only when I make the socket permission 666 it works correctly. Also when the permission is 660 but ownership is _rspamd:dovecot it works as well. I don't want the former as anyone could connect, and the latter can't be set automatically in Rspamd. I'm pulling my hairs out. I've tried to figure out the user and group that dovecot uses to run the sieve script (creatively by 'exit'ing the bash script with the uid or gid as error code), and they are both 97 (i.e. dovecot uid and gid). I've tried personally logging in as dovecot using 'sudo -u dovecot bash' and then using 'socat' to connect to the socket. This works fine. But through the dovecot sieve script for some reason it's not working. I've tried disabling SELinux and fapolicyd, but no luck. Is Dovecot using some restricted permissions when running sieve scripts? # dovecot --version 2.3.16 (7e2e900c1a) Thank you, Taco

1 1

Auth USER lookup failed
by thecoudge＠gmail.com 06 Feb '24

06 Feb '24

I have dovecot working with PAM and Samba DC authentication for IMAP. However when I'm attempting to pass emails from postfix via LMTP I don't actually need to authenticate LMTP I'm happy to check for valid users upstream. I'm getting the error: Feb 06 15:11:39 Debian-server postfix/local[178200]: ADF0E78713C: passing <dom.username(a)Debian-server.sr.local> to transport=lmtp Feb 06 15:11:39 Debian-server dovecot[178075]: auth: Error: static(dom.username): passdb doesn't support lookups, can't verify user's existence Feb 06 15:11:39 Debian-server dovecot[178075]: lmtp(dom.username(a)Debian-server.sr.local)<178233><GJ/9Nou/wWU5uAIAiShiCA:T2>: Error: auth-master: userdb lookup(dom.username(a)Debian-server.sr.local): Auth USER lookup failed Feb 06 15:11:39 Debian-server dovecot[178075]: lmtp(178233): Error: lmtp-server: conn unix:pid=178201,uid=111 [4]: rcpt dom.username(a)Debian-server.sr.local: Failed to lookup user dom.usernamey(a)Debian-server.sr.local: Internal error occurred. Refer to server log for more information. Doveconf -n: auth_username_format = %Ln disable_plaintext_auth = no mail_gid = vmail mail_location = maildir:/var/mail/virtual/%d/%n mail_privileged_group = mail mail_uid = vmail 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 = mail driver = pam } plugin { sieve = file:~/sieve;active=~/.dovecot.sieve } protocols = " imap lmtp lmtp" service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0666 user = postfix } } service lmtp { unix_listener /var/spool/postfix/private/dovecot-lmtp { group = postfix mode = 0600 user = postfix } } ssl_cert = </etc/dovecot/private/dovecot.pem ssl_client_ca_dir = /etc/ssl/certs ssl_dh = # hidden, use -P to show it ssl_key = # hidden, use -P to show it protocol lmtp { passdb { args = allow_all_users=yes driver = pam name = } }

2 1

possible wrong sql syntax ?
by Maurizio Caloro 06 Feb '24

06 Feb '24

hi i dont know exactly what succeeded but me alias don't run any more :-/ i know i used to be able to send mail via aliases from mae to markus(a)domain.com The names have of course been changed, simply for reasons of data protection. frendly asking i need little help, i think i have syntax mistake on mysql syntax call please why auth-worker don't find the alias mae, and send back "unknown user" ? emails send to markus(a)domain.com and also other mail adresses will run without problems. only the function alias no longer wants to. Feb 05 Time Dovecot/lmtp(279699): Info: Connect from local Feb 05 Time Dovecot/auth-worker(279700): Info: conn unix:auth-worker (pid=279685,uid=113): auth-worker<5>: sql(mae(a)domain.com): unknown user Feb 05 Time Dovecot/lmtp(279699): Info: Disconnect from local: Client has quit the connection (state=READY) dovecot.conf [snip] passdb { args = /etc/dovecot/dovecot-sql.conf driver = sql } userdb { args = /etc/dovecot/dovecot-sql.conf driver = sql } cat auth-sql.conf.ext [snip] passdb { driver = mysql args = /etc/dovecot/dovecot-sql.conf } userdb { driver = mysql args = /etc/dovecot/dovecot-sql.conf } # cat dovecot-sql.conf driver = mysql connect = host=localhost dbname=mailserver user=username password= default_pass_scheme = CRYPT user_query = SELECT '/srv/vmail/%d/%n' AS home, '10000' AS uid, '10000' AS gid, CONCAT('*:storage=', (quota*1024)) as quota_rule FROM mailbox WHERE username='%u' AND active = 1 password_query = SELECT username AS user, password, '/srv/vmail/%d/%n' AS userdb_home, '10000' AS userdb_uid, '10000' AS userdb_gid, CONCAT('maildir:storage=', (quota*1024)) as userdb_quota FROM mailbox WHERE username='%u' AND active = 1 yes this exist as mailbox # dovecot user markus(a)domain.com field value uid 10000 gid 10000 home /srv/vmail/domain.com/markus mail maildir:~/Maildir quota_rule *:storage=0 yes the mae are only a alias, so i think this are right!? # dovecot user mae(a)domain.com userdb lookup: user mae(a)domain.com doesn't exist field value MariaDB [mailserver]> SELECT * FROM mailbox; +------------------ +----------+--------+---------------------+------------+------------+---------+ | username | password | name | maildir | local_part | domain | active | +-------------------+----------+--------+---------------------+------------+------------+---------+ | markus(a)domain.com | ******** | markus | domain.com/markus/ | Markus M | domain.com | 1 | MariaDB [mailserver]> SELECT * FROM alias; +-----------------+--------------------+------------+--------+ | address | goto | domain | active | +-----------------+---------------------------------+--------+ | mae(a)domain.com | markus(a)domain.com | domain.com | 1 | +-----------------+---------------------------------+--------+ 34 rows in set (0.001 sec) dovecot --version 2.3.13 (89f716dc2) postconf mail_version 3.5.23 mysql Ver 15.1 Distrib 10.5.21-MariaDB debian 11 bullseye

1 0

Sieve question: Rewriting from using variables (ccsend issues)
by Ian Evans 06 Feb '24

06 Feb '24

As a journalist, I deal with a lot of PR companies that use constant contact. For years, I've built up a nice sieve filter that sports these people into my PR folder. I guess to help with dkim/SPF issues, Constant Contact has started rewriting the from header to the sender's address rewritten to end with a ccsend domain. The sender's actual email address is now in the reply-to header. This has resulted in all my PR emails ending up in the main inbox. Rather than rewrite hundreds of rules, I asked (foolishly?) ChatGPT if there was a way to check for ccsend in the from and then use the reply-to as the from. This is what it came up with and this would be the first rule in the sieve file: #Many PR companies use ccsend for lists. Check if headers contain "ccsend" and #then use reply-to for rules if allof (header :contains "from" "ccsend") { # Set "Reply-To" as "From" address set "from" "${reply-to}"; } Before I put this into production, will this work? Do the rest of the rules go inside the last curly bracket or after it? Thanks for any advice. As a journalist, I deal with a lot of PR companies that use constant contact. For years, I've built up a nice sieve filter that sports these people into my PR folder. I guess to help with dkim/SPF issues, Constant Contact has started rewriting the from header to the sender's address rewritten to end with a ccsend domain. The sender's actual email address is now in the reply-to header. This has resulted in all my PR emails ending up in the main inbox. Rather than rewrite hundreds of rules, I asked (foolishly?) ChatGPT if there was a way to check for ccsend in the from and then use the reply-to as the from. This is what it came up with and this would be the first rule in the sieve file: #Many PR companies use ccsend for lists. Check if headers contain "ccsend" and #then use reply-to for rules if allof (header :contains "from" "ccsend") { # Set "Reply-To" as "From" address set "from" "${reply-to}"; } Before I put this into production, will this work? Do the rest of the rules go inside the last curly bracket or after it? Thanks for any advice.

1 0

submission_add_received_header option?
by Ellie McNeill 05 Feb '24

05 Feb '24

Hi, I've recently upgraded my mail server from Debian 11 to Debian 12. It now runs dovecot 2.3.19.1 (verified with dovecot --version). According to the "Dovecot Core Settings" page, a new setting 'submission_add_received_header' was added in dovecot 2.3.19 to give admins the option of hiding the IP of the sending client when using dovecot's submissiond: https://doc.dovecot.org/3.0/settings/core/ However, when I place this option in my config, dovecot refuses to start and says that the option is not recognised: doveconf: Fatal: Error in configuration file /etc/dovecot/conf.d/20-submission.conf line 92: Unknown setting: submission_add_received_header Can anyone help me with this? Ellie

5 5

Recommended changes for delivery from Exim
by jgh＠exim.org 05 Feb '24

05 Feb '24

Hi, Security changes to Exim have invalidated certain suggested configurations in the Dovecot wiki. As I do not have a Dovecot installation to test, I am not going to write any updates there. It would be good if someone would test these suggestions and then make updates as needed. 1) The use of $local_part and $domain in commands run by the "pipe" transport will be disallowed in the upcoming Exim release. These are currently noted as optional, with the "-m" flag to dovecot-lda. They should be replaced with validated (untainted) versions, commonly $local_part_data and $domain_data, developed via one of the several de-taint methods documented for Exim. The same applies to $original_local_part and $original_domain. 2) The use of $sender_address will likewise be disallowed. This and the "-f" flag can be dropped from the dovecot-lda command line, and the specification of a null "message_prefix" option removed. The defaults for a pipe transport will then prefix the message with a suitable Mbox "From " header line, which dovecot-lda is documented to extract the sender from. Both of these suggestions are back-compatible to the current 4.95 release of Exim, and will be required with the 4.96 release. -- Cheers, Jeremy Refs: - https://wiki.dovecot.org/LDA/Exim - https://doc.dovecot.org/configuration_manual/protocols/lda/

3 3