- dovecot - dovecot.org

Dovecot - Microsoft Azure AD
by Lennart Boettcher 14 Aug '19

14 Aug '19

Hello, I am currently trying to connect my Dovecot mail server to Microsoft's Azure-AD and use it as password and user database. I am using version 2.3.7.1. Using the Azure-AD as passdb already works. In this context I noticed that the scope implementation is not yet merged. Since I haven't found any hints for an OAuth2 userdb implementation yet, I wanted to ask if there are any plans for an implementation. Greetings Lennart Boettcher

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Solr, Dovecot & macOS / iOS
by James Brown 14 Aug '19

14 Aug '19

I’m thinking of getting Solr working with my Dovecot server. Server is new 6-core Mac Mini, mail store of over 1/2 TB. Mailboxes with 100s of thousands of messages. But I’m not sure if: a) it will make enough of a difference and b) does Mail.app and other mail clients on Macs or iOS devices perform searches on their local copy of mail or does it just send a search request to the server? I’m guessing the searches are done locally so no point in Solr? Does anyone know? Thanks, James.

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Dovecot Sieve doesn't move spam to Junk folder in maildir
by Nagy Tibor 13 Aug '19

13 Aug '19

I have an *Ubuntu 16.04* mail server with postfix/spamassassin/*dovecot-2.2.2**2* with virtual mailboxes in maildir format. The whole process is working excellently since a year. Spams are marked with "*****SPAM*****" in subject and with "X-Spam-Flag: YES" in email header. I tried now to add sieve to dovecot to move the SPAM messages into the Junk folder without any success, I don't see any sign that sieve does something at all. The output of "dovecot -n": # 2.2.22 (fe789d2): /etc/dovecot/dovecot.conf # Pigeonhole version 0.4.13 (7b14904) # OS: Linux 4.4.0-72-generic x86_64 Ubuntu 16.04.2 LTS ext4 auth_mechanisms = cram-md5 auth_verbose = yes base_dir = /var/run/dovecot/ info_log_path = /var/log/dovecot.info log_path = /var/log/dovecot log_timestamp = "%Y-%m-%d %H:%M:%S " mail_location = maildir:/home/vmail/%d/%n 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 = yes location = prefix = separator = / } passdb { args = /etc/dovecot/passwd driver = passwd-file } plugin { sieve = /etc/dovecot/sieve/default.sieve } protocols = imap pop3 service auth { executable = /usr/lib/dovecot/auth unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0666 user = postfix } user = root } service imap-login { chroot = login executable = /usr/lib/dovecot/imap-login inet_listener imap { port = 0 } user = dovecot } service imap { executable = /usr/lib/dovecot/imap } service pop3-login { chroot = login executable = /usr/lib/dovecot/pop3-login inet_listener pop3 { port = 0 } inet_listener pop3s { port = 0 } user = dovecot } service pop3 { executable = /usr/lib/dovecot/pop3 } ssl_cert = </etc/ssl/certs/dovecot.pem ssl_key = </etc/ssl/private/dovecot.pem userdb { args = /etc/dovecot/users driver = passwd-file } valid_chroot_dirs = /var/spool/vmail protocol pop3 { pop3_uidl_format = %08Xu%08Xv } protocol lda { mail_plugins = " sieve" } I've added only plugin and protocol lda now. The content of the file default.sieve: require "fileinto"; if header :contains "X-Spam-Flag" "YES" { fileinto "Junk"; } The test SPAM message is marked as SPAM, but not moved to the folder Junk. I don't see anything in mail.log that is associated to sieve.: ul 30 20:05:12 zg-3 postfix/smtpd[4446]: connect from smtp4.enternet.hu[62.112.192.37] Jul 30 20:05:13 zg-3 postfix/smtpd[4446]: 3C4CC9F570: client=smtp4.enternet.hu[62.112.192.37] Jul 30 20:05:13 zg-3 postfix/cleanup[4450]: 3C4CC9F570: message-id=<c6b3bca5-ece3-9e69-8e30-28173abc2ec6(a)hu.inter.net> Jul 30 20:05:13 zg-3 postfix/qmgr[1557]: 3C4CC9F570: from=<nagyt(a)hu.inter.net>, size=918, nrcpt=1 (queue active) Jul 30 20:05:13 zg-3 postfix/smtpd[4446]: disconnect from smtp4.enternet.hu[62.112.192.37] ehlo=2 starttls=1 mail=1 rcpt=1 data=1 quit=1 commands=7 Jul 30 20:05:13 zg-3 postfix/pickup[3949]: 5F7FEA3CBC: uid=1003 from=<nagyt(a)hu.inter.net> Jul 30 20:05:13 zg-3 postfix/pipe[4451]: 3C4CC9F570: to=<tibor(a)softxs.ch>, relay=spamassassin, delay=0.15, delays=0.05/0.01/0/0.1, dsn=2.0.0, status=sent (delivered via spamassassin service) Jul 30 20:05:13 zg-3 postfix/qmgr[1557]: 3C4CC9F570: removed Jul 30 20:05:13 zg-3 postfix/cleanup[4450]: 5F7FEA3CBC: message-id=<c6b3bca5-ece3-9e69-8e30-28173abc2ec6(a)hu.inter.net> Jul 30 20:05:13 zg-3 postfix/qmgr[1557]: 5F7FEA3CBC: from=<nagyt(a)hu.inter.net>, size=3304, nrcpt=1 (queue active) Jul 30 20:05:13 zg-3 postfix/virtual[4455]: 5F7FEA3CBC: to=<tibor(a)softxs.ch>, relay=virtual, delay=0.02, delays=0.01/0.01/0/0, dsn=2.0.0, status=sent (delivered to maildir) Jul 30 20:05:13 zg-3 postfix/qmgr[1557]: 5F7FEA3CBC: removed What can be wrong?

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dovecot acl delete messages questions
by hfh＠cndns.com 13 Aug '19

13 Aug '19

Dovecot's acl plugin can prevent deletion of messages,it works very well! I want: Some ips can delete messages, other ips can not delete messages,can anyone help me? hfh(a)cndns.com

1 0

LastLogin update
by Jorge Bastos 13 Aug '19

13 Aug '19

Howdy, I'd like an adive on what to use. I have sql users, and i want to have the lastlogin of them, what is the native option for this: * Using last_login plugin which will give me the last login? * Use postlogin for imap and pop3n which will give me besides lastlogin the IP and protocol? Thanks in advanced,

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ACL ignored for master users
by Philip Iezzi 12 Aug '19

12 Aug '19

Hi there! I can't get ACL working for master users. Login as master user works fine though, and I am able to access any mailbox using the auth_master_user_separator "*", tested e.g. via Python's imaplib: >>> import imaplib >>> imap = imaplib.IMAP4_SSL('imap.example.com') >>> imap.login('foo(a)example.com*admin-acldemo', '**********') ('OK', [b'Logged in']) My /etc/dovecot/dovecot-acl looks like this: * user=admin lr bar(a)example.com user=admin-acldemo lr So, if I didn't misunderstand https://wiki.dovecot.org/Authentication/MasterUsers and https://wiki.dovecot.org/ACL documentation, this should only give "admin" master user access to all mailaccounts and limiting "admin-acldemo" master user to only a single mailaccount. But no matter what I put into dovecot-acl (it could even be empty), master users always have access to all existing mailaccounts. The whole dovecot-acl seems to be ignored and there are no logs pointing to any problem (syntax, access permissions) with that file. In mail.log I am getting a successful login message: dovecot: imap-login: Login: user=<foo(a)example.com>, method=PLAIN, rip=..., lip=..., mpid=42371, TLS, session=<T9GKEuyPKGxRPtGS> My current setup (relevant config options): # 2.3.7.1 (0152c8b10): /etc/dovecot/dovecot.conf # Pigeonhole version 0.5.7.1 (db5c74be) # OS: Linux 4.15.18-18-pve x86_64 Debian 9.9 auth_master_user_separator = * mail_plugins = quota acl passdb { args = /etc/dovecot/passwd.masterusers driver = passwd-file master = yes pass = yes } plugin { acl = vfile:/etc/dovecot/dovecot-acl acl_user = %u master_user = %u } protocol lmtp { mail_plugins = quota acl sieve } protocol lda { mail_plugins = quota acl sieve } protocol imap { mail_plugins = quota acl imap_acl imap_quota } On ACL documentation it says: > Note that master users have their own ACLs. They're not the the mailbox owners, so by default they have no permissions to any of the mailboxes and on Authentication/MasterUsers documentation: > If ACL plugin is enabled, the Master user is still subject to ACLs just like any other user, which means that by default the master user has no access to any mailboxes of the user. So it must be somehow possible to limit master users to specific mailbox(es) via ACL. If I disable `master = yes` master users won't be able to login at all. Any help greatly appreciated! Thanks in advance. Cheers, Philip

1 0

dovecot-lmtp and postfix
by Coy Hile 12 Aug '19

12 Aug '19

Hi all, I’ve got postfix setup to use dovecot-lmtp for (virtual) user delivery, and things to users or aliases that Dovecot knows about now get delivered correctly. However, I’ve done something wrong with postfix and/or the LMTP configuration because upon RCPT TO, instead of forwarding the mail off to the configured smartest, somehow dovecot-lmtp is ending up in the mix. (Perhaps this is more a postfix question than a dovecot one, but, I’ll start here.) Relevant postfix config: [root@81716ec5-bca4-6d53-ed81-bd1a55d46b4f /opt/local/etc/postfix]# postconf -n canonical_maps = hash:/opt/local/etc/postfix/canonical command_directory = /opt/local/sbin compatibility_level = 2 daemon_directory = /opt/local/libexec/postfix data_directory = /var/db/postfix debug_peer_level = 2 debugger_command = PATH=/bin:/usr/bin:/usr/local/bin:/usr/X11R6/bin ddd $daemon_directory/$process_name $process_id & sleep 5 default_database_type = hash home_mailbox = Maildir/ html_directory = no inet_interfaces = all inet_protocols = all mail_owner = postfix mailbox_size_limit = 102400000 mailq_path = /opt/local/bin/mailq manpage_directory = /opt/local/man message_size_limit = 51200000 meta_directory = /opt/local/libexec/postfix mynetworks = $myhostname, 127.0.0.0/8, 10.0.0.0/8, 172.16.0.0/12 192.168.0.0/16 newaliases_path = /opt/local/bin/newaliases owner_request_special = no queue_directory = /var/spool/postfix queue_minfree = 76800000 readme_directory = /opt/local/share/doc/postfix recipient_canonical_maps = hash:/opt/local/etc/postfix/recipient_canonical recipient_delimiter = + relayhost = relay.svc.a4b01392-e48d-4cdf-cacf-f850d1800d45.basement.cns.coyhile.com sample_directory = /opt/local/share/examples/postfix sender_canonical_maps = hash:/opt/local/etc/postfix/sender_canonical sendmail_path = /opt/local/sbin/sendmail setgid_group = maildrop shlib_directory = /opt/local/lib/postfix smtpd_banner = $myhostname ESMTP smtpd_client_restrictions = permit_mynetworks, permit_sasl_authenticated, reject_unknown_reverse_client_hostname smtpd_data_restrictions = permit_mynetworks, reject_unauth_pipelining, permit_sasl_authenticated smtpd_helo_required = yes smtpd_helo_restrictions = permit_mynetworks, permit_sasl_authenticated, reject_invalid_helo_hostname, reject_non_fqdn_helo_hostname smtpd_recipient_restrictions = permit_mynetworks, permit_sasl_authenticated, reject_unlisted_recipient, reject_non_fqdn_recipient, reject_unauth_destination, reject_unknown_recipient_domain, check_recipient_access hash:/opt/local/etc/postfix/filtered_domains smtpd_sasl_auth_enable = yes smtpd_sasl_path = private/auth smtpd_sasl_type = dovecot smtpd_sender_restrictions = permit_mynetworks, permit_sasl_authenticated, reject_unlisted_sender, reject_non_fqdn_sender, reject_unknown_sender_domain smtputf8_enable = no strict_rfc821_envelopes = yes unknown_local_recipient_reject_code = 550 virtual_alias_maps = pgsql:/opt/local/etc/postfix/postfix_virtual_aliases.cf virtual_mailbox_domains = pgsql:/opt/local/etc/postfix/postfix_virtual_domains.cf virtual_transport = lmtp:unix:private/dovecot-lmtp [root@81716ec5-bca4-6d53-ed81-bd1a55d46b4f /opt/local/etc/postfix]# And the dovecot config: doveconf -n # 2.3.6 (7eab80676): /opt/local/etc/dovecot/dovecot.conf # Pigeonhole version 0.5.6 (92dc263a) doveconf: Warning: NOTE: You can get a new clean config file with: doveconf -Pn > dovecot-new.conf doveconf: Warning: Obsolete setting in /opt/local/etc/dovecot/conf.d/10-ssl.conf:80: ssl_dh_parameters_length is no longer needed doveconf: Warning: Obsolete setting in /opt/local/etc/dovecot/conf.d/10-ssl.conf:81: ssl_protocols has been replaced by ssl_min_protocol doveconf: Warning: NOTE: You can get a new clean config file with: doveconf -Pn > dovecot-new.conf doveconf: Warning: Obsolete setting in /opt/local/etc/dovecot/conf.d/10-ssl.conf:80: ssl_dh_parameters_length is no longer needed doveconf: Warning: Obsolete setting in /opt/local/etc/dovecot/conf.d/10-ssl.conf:81: ssl_protocols has been replaced by ssl_min_protocol doveconf: Warning: service auth { client_limit=840 } is lower than required under max. load (1524) # OS: SunOS 5.11 i86pc # Hostname: 81716ec5-bca4-6d53-ed81-bd1a55d46b4f.coyhile.com auth_mechanisms = plain login auth_socket_path = /var/run/dovecot/auth-userdb imap_idle_notify_interval = 29 mins lda_mailbox_autocreate = yes lda_mailbox_autosubscribe = yes mail_attachment_dir = /var/mail/attachments mail_fsync = never mail_location = mdbox:~/mdbox mail_plugins = " acl" mail_privileged_group = 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 imapsieve vnd.dovecot.imapsieve 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 = /opt/local/etc/dovecot/dovecot-sql.conf.ext driver = sql } plugin { acl_defaults_from_inbox = yes imapsieve_mailbox1_before = file:/etc/dovecot/sieve/report-spam.sieve imapsieve_mailbox1_causes = COPY imapsieve_mailbox1_name = Junk imapsieve_mailbox2_before = file:/etc/dovecot/sieve/report-ham.sieve imapsieve_mailbox2_causes = COPY imapsieve_mailbox2_from = Junk imapsieve_mailbox2_name = * sieve = file:~/sieve;active=~/.dovecot.sieve sieve_global_extensions = +vnd.dovecot.pipe sieve_pipe_bin_dir = /etc/dovecot/sieve sieve_plugins = sieve_imapsieve sieve_extprograms } protocols = imap pop3 lmtp submission service auth-worker { user = vmail } service auth { client_limit = 840 inet_listener { port = 2222 } unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0666 user = postfix } unix_listener auth-userdb { group = vmail mode = 0666 user = vmail } } service imap-login { inet_listener imaps { port = 993 ssl = yes } process_min_avail = 3 service_count = 0 vsz_limit = 1 G } service imap { process_min_avail = 3 service_count = 256 } service lmtp { unix_listener /var/spool/postfix/private/dovecot-lmtp { group = postfix mode = 0600 user = postfix } } service pop3-login { inet_listener pop3 { port = 0 } inet_listener pop3s { port = 0 } } ssl_cert = </opt/local/etc/dovecot/certs/dovecot.pem ssl_cipher_list = ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA384:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA256 ssl_key = # hidden, use -P to show it ssl_min_protocol = TLSv1.2 ssl_prefer_server_ciphers = yes userdb { args = /opt/local/etc/dovecot/dovecot-sql.conf.ext driver = sql } protocol lmtp { mail_plugins = " acl sieve" } protocol lda { mail_plugins = " acl sieve" } protocol imap { mail_max_userip_connections = 50 mail_plugins = " acl imap_acl imap_sieve” } And in syslog I see: 2019-08-11T15:37:57+00:00 81716ec5-bca4-6d53-ed81-bd1a55d46b4f postfix/smtpd[56103]: [ID 197553 mail.info] 12327F13D: client=ns1.coyhile.com[172.17.64.25] 2019-08-11T15:38:40+00:00 81716ec5-bca4-6d53-ed81-bd1a55d46b4f postfix/cleanup[56365]: [ID 197553 mail.info] 12327F13D: message-id=<> 2019-08-11T15:38:40+00:00 81716ec5-bca4-6d53-ed81-bd1a55d46b4f postfix/qmgr[56018]: [ID 197553 mail.info] 12327F13D: from=<coy.hile(a)coyhile.com>, size=354, nrcpt=1 (queue active) 2019-08-11T15:38:40+00:00 81716ec5-bca4-6d53-ed81-bd1a55d46b4f dovecot: [ID 702911 mail.info] lmtp(50179): Connect from local 2019-08-11T15:38:40+00:00 81716ec5-bca4-6d53-ed81-bd1a55d46b4f postfix/lmtp[56821]: [ID 197553 mail.info] 12327F13D: to=<coyhile(a)gmail.com>, relay=81716ec5-bca4-6d53-ed81-bd1a55d46b4f.localdomain[private/dovecot-lmtp], delay=55, delays=55/0.01/0/0.03, dsn=5.1.1, status=bounced (host 81716ec5-bca4-6d53-ed81-bd1a55d46b4f.localdomain[private/dovecot-lmtp] said: 550 5.1.1 <coyhile(a)gmail.com> User doesn't exist: coyhile(a)gmail.com (in reply to RCPT TO command)) Given both of those configurations, shouldn’t it see that gmail address and send it off to the relay host? -Coy

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Gmail to Dovecot migration
by Yuri 12 Aug '19

12 Aug '19

Hi everyone, I'm trying to migrate my gmail to dovecot following instructions at https://wiki.dovecot.org/Migration/Gmail Using -a 'virtual/All' option does not seem to work because the gmail folder with that name does not exist, but -a '[Gmail]/All Mail' seem to work. I'm using the following command: sudo doveadm \ -o imapc_host=imap.gmail.com \ -o imapc_user=user(a)gmail.com \ -o imapc_password=gmailpassword \ -o imapc_features="rfc822.size gmail-migration" \ -o imapc_port=993 \ -o imapc_ssl=imaps \ -o ssl_client_ca_dir=/etc/ssl/certs \ -o imapc_ssl_verify=yes \ backup -a '[Gmail]/All Mail' -O '-$GmailHaveLabels' -R -u user(a)exmaple.com imapc: The problem is this command only migrates approximately 25% of my emails by size. Google Takeout exports 4 times more data in mbox format, the size of exported mboxes aligns with what Google tells me a the bottom of gmail settings page. I experimented with other options of 'doveadm backup' command, but they all resulted in less data being migrated. The above options are the best I was able to achive so far. Another option I was considering is to convert Google Takeout mboxes to dovecot format. I tried using 'doveadm import' command, but got confused with various user and search query options of the command. The best I was able to achive was to output a folder under /Takeout which mimics my mbox structure, but with no imported messages. A third option I'm considering is to convert Google Takeout mboxes using mb2md command. Conversion seems to work fine, but the output is in the traditional (dotted) format, and for historical reasons I use 'LAYOUT=fs' option. So I need to do some extra work to convert folder names. And even if I do so, I'm still not sure if I can import Maildir to dovecot because dovecot's Maildir has other information, such as indices, logs, etc., not just email folders. I'll keep investigating the second and the third option because it seems that Google Takeout gives me all my emails, but I'm not sure if those are the right paths. I wanted to ask the experts about the best option to migrate gmail to dovecot. Has anyone being able to successfully migrate all their emails from gmail and what steps have been used for that? My Dovecot version: 2.3.4.1 Thank you, Yuri

1 1

What does `iterate_query` for SQL want as output?
by Coy Hile 10 Aug '19

10 Aug '19

Hi all, In an earlier thread, https://dovecot.org/pipermail/dovecot/2019-August/116694.html I got a lot of useful help about migration. On my older host, everything was static; on the newer host, I’m storing user information in Postgres. usernames are of the form <login@REALM>, say ‘hile(a)coyhile.xn--com-to0a as basically a Kerberos principal, and authentication and individual lookups work. My `users` table looks thus: mail=> \d users Table "public.users" Column | Type | Modifiers ----------+------+----------- username | text | not null domain | text | not null password | text | not null mail=> and contains, as an example: username | domain | password ------------------+-------------+------------------------------------------------------------------------------------------------------- hile(a)coyhile.com | coyhile.com | [REDACTED] (1 row) Naively, I’d expect something this to work for the iteration query: iterate_query = SELECT username, domain FROM users But, when I do that, I end up doveadm backup -D -A -R -f ssh -i id_rsa.dsync imap01.coyhile.com /opt/local/bin/doveadm dsync-server -A doveadm(hile@coyhile.com@coyhile.com): Info: User no longer exists, skipping [root@81716ec5-bca4-6d53-ed81-bd1a55d46b4f /tmp]# Note the extra “(a)coyhile.xn--com-9o0a in there. Thanks, — Coy Hile coy.hile(a)coyhile.com

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Auth driver
by Riccardo Paolo Bestetti 09 Aug '19

09 Aug '19

Greetings! I'm planning to implement a new auth driver. It's going to be, in concept, similar to the Lua and CheckPassword drivers, in that it allows an user program to carry out the authentication and user enumeration steps. The rationale is that such a solution would provide better decoupling between Dovecot and the user authentication and enumeration logic. Existing integrated logic (auth/ directory in the source tree) is, even encompassing a great number of common use cases, ultimately inflexible. Writing custom drivers implementing logic, while being a solution to the inflexibility problem, is clearly not what drivers were engineered for: for one they don't support dynamic loading, making it necessary to recompile Dovecot to make changes, which is unacceptable in many situations, e.g. when using a packaged or containerized version of the software. In this email, I intend to explain what characteristics my driver will have and why it solves the proposed problem better than existing code (such as CheckPassword, Lua and proxy), in the hope to get useful feedback and I will pose some technical questions to which I could not find definitive answers by myself yet. These are going to be the characteristics of my driver (with particular emphasis to the differences to the existing drivers): - It is going to be a completely generic mechanism exposing all funcionality of Dovecot's interface, both password check and enumeration, and will fully support authentication methods with continuations. - It is going to be performant, communicating with external programs through sockets (unix or inet). - It is going to communicate using a simple, dynamic-schema, well-understood protocol, which is probably going to be JSON, being very easy to generate and parse. This is why the existing drivers do not already provide what I described: - CheckPassword is heavy (fork & 2*exec), and it's generally a mess, having initially been provided as a compatibility feature and having then been hacked to support additional functionality; it's architecturally unfeasable to support continuations with it and anyway any further extension will probably make it explode :) - Lua works but it's limited, in that it dictates a language and also dictates that the auth logic should run on the same server as Dovecot (and under Dovecot's control). It also doesn't seem to support plain password checks, but only user-password enumeration, making it non-generic (at least this is what can be inferred from the documentation and examples.) - Other possible solutions, such as (mis)using the proxy driver to communicate with an external program are not well documented and nothing guarantees the proxy protocol will not change anyway, being an internal feature. And now, the technical questions. I know these could be answered by reading the code, which is something I'm doing, but I'm finding some architectural details quite difficult to grasp due to their complexity: - From what I gather from [1], auth-worker processes only process a single request before being killed from auth. Would setting service_count to something different cause auth-workers to be reused or would it just leak the auth-workers? In the first case, is the preinit of the auth driver repeated, or is the existing instance of the auth driver reused? You could also point me to the relevant code sections which start, keep track of and initialize auth-workers. - How does a driver specify what to run in an auth-worker as opposed to in the auth process? (This is strongly related to the first question, and maybe it is more general, so you may want to answer this one first.) Please, feel free to only answer parts of my email. Any input on any of the matters is very welcome. Best regards, Riccardo P. Bestetti [1] https://wiki.dovecot.org/Services#auth-worker

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