- dovecot - dovecot.org

Re: User authentication for shared mailbox
by Stéphane Veyret 31 May '26

31 May '26

I managed to make it work. In case some other people want to do the same, the trick was to use the master user concept, as suggested by Aki Tuomi, with a lua script to check if user can be master. My configuration looks like this: passdb pam_master { driver = pam master = yes result_success = continue } passdb pam { } passdb lua { lua_file = /etc/dovecot/master-auth.lua result_failure = return-fail result_internalfail = return-fail result_success = continue-ok } passdb ldap { ldap_base = ou=Group,dc=example,dc=com fields { password = {SHA1}IQ== user = %{ldap:cn} } filter = (cn=%{user | username}) } and the lua script: function script_init() return 0 end function auth_passdb_lookup(req) if req.master_user then req:log_info("Looking for groups for " .. tostring(req.master_user)) handle = io.popen("/bin/groups " .. tostring(req.master_user)) output = handle:read("*a") req:log_debug("Searching " .. tostring(req.user) .. " in found groups " .. output) for group in output:gmatch("%w+") do if group == req.user then return dovecot.auth.PASSDB_RESULT_OK, { password="!" } end end end return dovecot.auth.PASSDB_RESULT_USER_UNKNOWN, "No such user" end -- Bien cordialement, / Plej kore, Stéphane Veyret I managed to make it work. In case some other people want to do the same, the trick was to use the master user concept, as suggested by Aki Tuomi, with a lua script to check if user can be master. My configuration looks like this: passdb pam_master { driver = pam master = yes result_success = continue } passdb pam { } passdb lua { lua_file = /etc/dovecot/master-auth.lua result_failure = return-fail result_internalfail = return-fail result_success = continue-ok } passdb ldap { ldap_base = ou=Group,dc=example,dc=com fields { password = {SHA1}IQ== user = %{ldap:cn} } filter = (cn=%{user | username}) } and the lua script: function script_init() return 0 end function auth_passdb_lookup(req) if req.master_user then req:log_info("Looking for groups for " .. tostring(req.master_user)) handle = io.popen("/bin/groups " .. tostring(req.master_user)) output = handle:read("*a") req:log_debug("Searching " .. tostring(req.user) .. " in found groups " .. output) for group in output:gmatch("%w+") do if group == req.user then return dovecot.auth.PASSDB_RESULT_OK, { password="!" } end end end return dovecot.auth.PASSDB_RESULT_USER_UNKNOWN, "No such user" end -- Bien cordialement, / Plej kore, Stephane Veyret

1 0

dsync between 2.3.16 and 2.4.2
by Jean-Daniel Beaubien 28 May '26

28 May '26

Hi, I currently have a doveadm backup running my prod and backup server. Both are currently running 2.3.16, and the following command runs fine: sudo doveadm -v backup -u XXXX -P remote:XXXX@192.168.111.XX I am in the process of updating my servers to ubuntu 26.04 which runs dovecot 2.4.2 and I am running into problems trying to run this command. For some reason, it tries to delete the INBOX on the destination and I get the following error: dsync-remote(XXXX)<7hkbKDl6F2rlxQAArPp36Q>: Error: brain S: Mailbox INBOX sync: mailbox_delete failed: The /private/specialuse attribute cannot be changed doveadm(228686): Error: Remote command returned error 65: ssh -lXXXX 192.168.111.XX doveadm dsync-server -uXXXX I am not sure what/why this is happening. I read the docs and man page, but could not find a solution. Anyone knows what is happening, and how to solve this? Thanks, -JD ----- Addendum ----- Another thing that might help someone else: I had to add a line to the config file to avoid the -U problem: dsync_remote_cmd = "ssh -l%{login} %{host} doveadm dsync-server -u%{user}" This seems to already be solved ( https://dovecot.org/mailman3/archives/list/dovecot@dovecot.org/thread/B3TQF…) but not yet in the ubuntu 26.04 release? Hi, I currently have a doveadm backup running my prod and backup server. Both are currently running 2.3.16, and the following command runs fine: sudo doveadm -v backup -u XXXX -P remote:XXXX@192.168.111.XX I am in the process of updating my servers to ubuntu 26.04 which runs dovecot 2.4.2 and I am running into problems trying to run this command. For some reason, it tries to delete the INBOX on the destination and I get the following error: dsync-remote(XXXX)<7hkbKDl6F2rlxQAArPp36Q>: Error: brain S: Mailbox INBOX sync: mailbox_delete failed: The /private/specialuse attribute cannot be changed doveadm(228686): Error: Remote command returned error 65: ssh -lXXXX 192.168.111.XX doveadm dsync-server -uXXXX I am not sure what/why this is happening. I read the docs and man page, but could not find a solution. Anyone knows what is happening, and how to solve this? Thanks, -JD ----- Addendum ----- Another thing that might help someone else: I had to add a line to the config file to avoid the -U problem: dsync_remote_cmd = "ssh -l%{login} %{host} doveadm dsync-server -u%{user}" This seems to already be solved ([1]https://dovecot.org/mailman3/archives/list/dovecot@dovecot.org/thread/B3T…) but not yet in the ubuntu 26.04 release? References Visible links 1. https://dovecot.org/mailman3/archives/list/dovecot@dovecot.org/thread/B3TQF…

2 1

I can't find up to date documentation about dovecot authentication process design
by kristoffermollerhoj＠gmail.com 27 May '26

27 May '26

Hi, I am currently about to port a legacy / custom authentication mechanism from 2.3 to 2.4. Many things have changed in this area, and I have unfortunately not been able to find any valid documentation about this topic. I have looked here: https://doc.dovecot.org/2.4.4/developers/design/auth_process.html but as far as I can see all the content is about the code design for dovecot 2.3, not 2.4. Just to mention a few examples: There is not anymore a struct named mech_module, there is no such file as mech.h, and also the API for the central callback functions such as auth_new() and auth_initial() seems to have changed a lot (both arguments and return types). Maybe a somewhat unfinished version of the documentation can be found on a specific branch? Thank you, Kristoffer Møllerhøj.

4 5

Sent, Junk and Drafts are not created
by Thomas Jensen 26 May '26

26 May '26

I have a new dovecot 2.4.2 setup. All seems to work fine, except Sent, Junk and Drafts are not created. In 15-mailboxes.conf I have: namespace inbox { # These mailboxes are widely used and could perhaps be created automatically: mailbox Drafts { auto = create special_use = \Drafts } mailbox Junk { auto = create special_use = \Junk } mailbox Trash { auto = create special_use = \Trash } # For \Sent mailboxes there are two widely used names. We'll mark both of # them as \Sent. User typically deletes one of them if duplicates are created. mailbox Sent { auto = create special_use = \Sent } mailbox "Sent Messages" { auto = create special_use = \Sent } } But nothing is created. And dovecot -n return this: (note the "\\") root@rpix:~# dovecot -n # 2.4.2 (0962ed2104): /etc/dovecot/dovecot.conf # Pigeonhole version 2.4.2 (767418c3) # OS: Linux 7.0.0-15-generic x86_64 Ubuntu 26.04 LTS # Hostname: rpix.dk # 9 default setting changes since version 2.4.0 dovecot_config_version = 2.4.0 auth_default_domain = rpix.dk auth_mechanisms = plain login auth_username_format = %{user|lower} dovecot_storage_version = 2.4.0 fts_autoindex = yes fts_autoindex_max_recent_msgs = 999 fts_search_add_missing = yes mail_driver = maildir mail_home = /var/vmail/%{user | domain}/%{user | username} mail_path = ~/Maildir mail_privileged_group = mail protocols = imap lmtp sql_driver = mysql ssl = required passdb sql { default_password_scheme = ARGON2I query = SELECT username AS user,password FROM mailbox WHERE username = '%{user}' AND active='1' } userdb sql { iterate_query = SELECT username AS user FROM mailbox query = SELECT 2000 AS uid, 2000 AS gid FROM mailbox WHERE username = '%{user}' AND active='1' } mysql localhost { dbname = postfixadmin password = # hidden, use -P to show it user = postfixadmin } namespace inbox { inbox = yes mailbox Drafts { auto = create special_use = "\\Drafts" } mailbox Junk { auto = create special_use = "\\Junk" } mailbox Trash { auto = create special_use = "\\Trash" } mailbox Sent { auto = create special_use = "\\Sent" } mailbox "Sent Messages" { auto = create special_use = "\\Sent" } } service imap-login { inet_listener imap { } inet_listener imaps { } } service pop3-login { inet_listener pop3 { } inet_listener pop3s { } } service submission-login { inet_listener submission { } inet_listener submissions { } } service lmtp { unix_listener /var/spool/postfix/private/dovecot-lmtp { group = postfix mode = 0600 user = postfix } } service imap { } service pop3 { } service submission { } service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0666 user = postfix } } service auth-worker { } service dict { unix_listener dict { } } service stats { unix_listener stats-reader { group = www-data mode = 0660 user = www-data } unix_listener stats-writer { group = www-data mode = 0660 user = www-data } } ssl_server { cert_file = /etc/letsencrypt/live/mail/fullchain.pem key_file = /etc/letsencrypt/live/mail/privkey.pem prefer_ciphers = server } protocol lmtp { auth_username_format = %{user | lower} } What am I doing wrong? -- /Thomas Jensen, Denmark

3 3

Possible FTS language detection packaging issue in Dovecot 2.4.x Debian packages
by Jens Urban 26 May '26

26 May '26

Hello, Is anyone running Dovecot 2.4.4 with multilingual FTS flatcurve on Debian 12/13, using the packages from Dovecot.org? I suspect a packaging/build issue related to language detection. It looks like libexttextcat is not included in the Debian build. Simple reproduction with doveadm: doveadm fts tokenize -u localpart@domain 'This is the house. Das ist das Haus‘ —> Warning: Can't detect its language - assuming de …… My suspicion: If the "libexttextcat-dev" package was not installed during the "configure" step of the package creation process, then "HAVE_LANG_EXTTEXTCAT" will not be set. And if the define "HAVE_LANG_EXTTEXTCAT" is not set during the compilation of "src/lib-language/language.c", then "language_textcat_init" always returns "LANGUAGE_DETECT_RESULT_UNKNOWN;". Consequently, doveadm invariably translates this return value into the message: "Warning: Can't detect its language - assuming $DEFAULT-LANG". If I download the source code from Dovecot.org and build the dovecot vendor package myself, "language detection" works—provided that "libexttextcat-dev" has been installed beforehand. My simple test to check whether the installed version contains „libexttextcat“: (My build finds references to libexttextcat; the build from Dovecot.org finds none.) nm --print-file-name --dynamic --undefined-only /usr/lib/x86_64-linux-gnu/dovecot/* | grep textcat —> /usr/lib/x86_64-linux-gnu/dovecot/libdovecot-language.so.0.0.0: U special_textcat_Init —> /usr/lib/x86_64-linux-gnu/dovecot/libdovecot-storage.so.0.0.0: U textcat_ReleaseClassifyFullOutput Background: In my self-built package, exttextcat-related symbols appear in both libdovecot-language and libdovecot-storage; I assume this is expected due to the build/link layout. Regards, Jens Hello, Is anyone running Dovecot 2.4.4 with multilingual FTS flatcurve on Debian 12/13, using the packages from Dovecot.org? I suspect a packaging/build issue related to language detection. It looks like libexttextcat is not included in the Debian build. Simple reproduction with doveadm: doveadm fts tokenize -u localpart@domain 'This is the house. Das ist das HausaEUR~ aEUR"> Warning: Can't detect its language - assuming de aEUR|aEUR| My suspicion: If the "libexttextcat-dev" package was not installed during the "configure" step of the package creation process, then "HAVE_LANG_EXTTEXTCAT" will not be set. And if the define "HAVE_LANG_EXTTEXTCAT" is not set during the compilation of "src/lib-language/language.c", then "language_textcat_init" always returns "LANGUAGE_DETECT_RESULT_UNKNOWN;". Consequently, doveadm invariably translates this return value into the message: "Warning: Can't detect its language - assuming $DEFAULT-LANG". If I download the source code from Dovecot.org and build the dovecot vendor package myself, "language detection" worksaEUR"provided that "libexttextcat-dev" has been installed beforehand. My simple test to check whether the installed version contains aEURzlibexttextcataEURoe: (My build finds references to libexttextcat; the build from Dovecot.org finds none.) nm --print-file-name --dynamic --undefined-only /usr/lib/x86_64-linux-gnu/dovecot/* | grep textcat aEUR"> /usr/lib/x86_64-linux-gnu/dovecot/libdovecot-language.so.0.0.0: U special_textcat_Init aEUR"> /usr/lib/x86_64-linux-gnu/dovecot/libdovecot-storage.so.0.0.0: U textcat_ReleaseClassifyFullOutput Background: In my self-built package, exttextcat-related symbols appear in both libdovecot-language and libdovecot-storage; I assume this is expected due to the build/link layout. Regards, Jens

1 0

dovecot 2.4.4 community edition, bug in variables
by Terry Braun 23 May '26

23 May '26

I'm using this passdb sql to a postgres db passdb sql { query = SELECT NULL AS password, 'Y' as nopassword, userid AS user \ FROM users \ WHERE addr = '%{user}' AND password = '%{password}' } This succeed and the addr passed in as user is foo(a)example.com as expected I use this userdb sql userdb sql { query = SELECT home, uid, gid \ FROM users \ WHERE addr = '%{user}' # For using doveadm -A: # iterate_query = SELECT userid AS username, domain FROM users } This fails because postgres receives just "foo" not "foo(a)example.com" as user. maybe there is a bug in my stuff but I cannot see it. I can see the query in the postgres log where it clearly says: WHERE addr = 'foo' It also logs the passdb query: WHERE addr = 'foo(a)example.com' AND password='secret' thanks Terry

2 2

Problem with authentication in dovecot
by Freek de Kruijf 22 May '26

22 May '26

I have the following dovecot.conf, striped from comment: dovecot_config_version = 2.4.2 dovecot_storage_version = 2.4.0 protocols = imap auth_allow_cleartext = yes auth_mechanisms = plain auth_verbose = yes mail_plugin_dir = /usr/lib64/dovecot/modules namespace inbox { inbox = yes mail_driver = maildir mail_path = ~/Maildir prefix = INBOX. mailbox Drafts { special_use = \Drafts } mailbox Junk { special_use = \Junk } mailbox Trash { auto = subscribe special_use = \Trash } mailbox Sent { special_use = \Sent } mailbox "Sent Messages" { special_use = \Sent } } passdb pam { service_name = dovecot } userdb passwd { use_worker = yes } service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0666 user = postfix } } ssl = yes ssl_server { cert_file = /etc/letsencrypt/live/<mydomain>/fullchain.pem dh_file = /etc/dovecot/dh.pem key_file = /etc/letsencrypt/live/<mydomain>/privkey.pem } sieve_script personal { active_path = ~/.dovecot.sieve driver = file path = ~/sieve } When connecting my email client to dovecot, the connection succeeds, but after awhile it disconnects. In /var/log/dovecot I get: May 18 17:36:15 imap-login: Warning: Auth process not responding, delayed sending initial response (greeting): user=<>, rip=192.168.178.6, lip=192.168.178.15, session=<2IMbUhlS8K3AqLIG> May 18 17:36:45 imap-login: Info: Login aborted: Connection closed (disconnected before auth was ready, waited 40 secs) (auth_process_not_ready): user=<>, rip=192.168.178.6, lip=192.168.178.15, session=<2IMbUhlS8K3AqLIG> May 18 17:36:45 imap-login: Error: auth-client: conn unix:login: connect(login) in directory / failed: Permission denied (euid=473(<getpwuid() error>) egid=473(<getgrgid() error>) missing +x perm: /, we're not in group 474, dir owned by 0:474 mode=0750) May 18 17:36:45 imap-login: Error: auth-client: conn unix:login: connect(login) in directory / failed: Permission denied (euid=473(<getpwuid() error>) egid=473(<getgrgid() error>) missing +x perm: /, we're not in group 474, dir owned by 0:474 mode=0750) 473 is connected with account/group dovenull an 474 is connected with account/group dovecot I can't find a solution when searching the internet. -- fr.gr. member openSUSE Freek de Kruijf I have the following dovecot.conf, striped from comment: dovecot_config_version = 2.4.2 dovecot_storage_version = 2.4.0 protocols = imap auth_allow_cleartext = yes auth_mechanisms = plain auth_verbose = yes mail_plugin_dir = /usr/lib64/dovecot/modules namespace inbox { inbox = yes mail_driver = maildir mail_path = ~/Maildir prefix = INBOX. mailbox Drafts { special_use = \Drafts } mailbox Junk { special_use = \Junk } mailbox Trash { auto = subscribe special_use = \Trash } mailbox Sent { special_use = \Sent } mailbox "Sent Messages" { special_use = \Sent } } passdb pam { service_name = dovecot } userdb passwd { use_worker = yes } service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0666 user = postfix } } ssl = yes ssl_server { cert_file = /etc/letsencrypt/live/<mydomain>/fullchain.pem dh_file = /etc/dovecot/dh.pem key_file = /etc/letsencrypt/live/<mydomain>/privkey.pem } sieve_script personal { active_path = ~/.dovecot.sieve driver = file path = ~/sieve } When connecting my email client to dovecot, the connection succeeds, but after awhile it disconnects. In /var/log/dovecot I get: May 18 17:36:15 imap-login: Warning: Auth process not responding, delayed sending initial response (greeting): user=<>, rip=192.168.178.6, lip=192.168.178.15, session=<2IMbUhlS8K3AqLIG> May 18 17:36:45 imap-login: Info: Login aborted: Connection closed (disconnected before auth was ready, waited 40 secs) (auth_process_not_ready): user=<>, rip=192.168.178.6, lip=192.168.178.15, session=<2IMbUhlS8K3AqLIG> May 18 17:36:45 imap-login: Error: auth-client: conn unix:login: connect(login) in directory / failed: Permission denied (euid=473(<getpwuid() error>) egid=473(<getgrgid() error>) missing +x perm: /, we're not in group 474, dir owned by 0:474 mode=0750) May 18 17:36:45 imap-login: Error: auth-client: conn unix:login: connect(login) in directory / failed: Permission denied (euid=473(<getpwuid() error>) egid=473(<getgrgid() error>) missing +x perm: /, we're not in group 474, dir owned by 0:474 mode=0750) 473 is connected with account/group dovenull an 474 is connected with account/group dovecot I can't find a solution when searching the internet. -- fr.gr. member openSUSE Freek de Kruijf

3 4

Regression/Bug report: crypt_private_key_file (for crypt_global_private_key) no longer supports inline base64 (from userdb) in dev branch
by Ömer Güven 22 May '26

22 May '26

Hi, I’ve run into what appears to be a regression (or at least a behavioral change) in Dovecot 3.3.0+ / current HEAD regarding crypt_private_key_file handling for the crypt_global_private_key. I don‘t use per-folder user keys but a global encryption key per user. Previously, it was possible to provide the private key via userdb using an inline base64:-encoded PEM directly to the crypt_global_private_key_file and Dovecot would correctly parse and use it. With the latest config scheme change, this no longer works, as you cannot really set named config variables from userdb. I did workaround by setting a custom userdb variable and setting the needed named/filter variables manually in the config file. To make it work, I had to enclose the config in a „protocol imap“ scope. The crypt_global_public_key_file is accessible from userdb (as it is not within a named filter scope), so inline-base64 works as with Dovecot 2.3+. When using the following workaround to reach the scoped variables, Dovecot tries to load the file „inline:BASE64ENCODEDPEM“ as a literal filename (error open(inline:AB….C==) failed): protocol imap { crypt_global_private_key user { crypt_private_key_file = %{userdb:private_key_file} crypt_private_key_password = %{userdb:private_key_password} } } As a workaround, I now have to: • store the private key as a file (e.g. %{home}/privkey.pem) • pass only the password via userdb • inject the path indirectly via static config + userdb variables This works, but is less elegant: protocol imap { crypt_global_private_key user { crypt_private_key_file = %{home}/privkey.pem crypt_private_key_password = %{userdb:private_key_password} } } Again, with the new named filter mechanism, it’s no longer possible to directly inject such config values via userdb, which makes fully dynamic per-user key provisioning harder. I now have to export all encrypted private keys from the database to the users home directory. Ömer Hi, I've run into what appears to be a regression (or at least a behavioral change) in Dovecot 3.3.0+ / current HEAD regarding crypt_private_key_file handling for the crypt_global_private_key. I don`t use per-folder user keys but a global encryption key per user. Previously, it was possible to provide the private key via userdb using an inline base64:-encoded PEM directly to the crypt_global_private_key_file and Dovecot would correctly parse and use it. With the latest config scheme change, this no longer works, as you cannot really set named config variables from userdb. I did workaround by setting a custom userdb variable and setting the needed named/filter variables manually in the config file. To make it work, I had to enclose the config in a "protocol imap" scope. The crypt_global_public_key_file is accessible from userdb (as it is not within a named filter scope), so inline-base64 works as with Dovecot 2.3+. When using the following workaround to reach the scoped variables, Dovecot tries to load the file "inline:BASE64ENCODEDPEM" as a literal filename (error open(inline:AB....C==) failed): protocol imap { crypt_global_private_key user { crypt_private_key_file = %{userdb:private_key_file} crypt_private_key_password = %{userdb:private_key_password} } } As a workaround, I now have to: o store the private key as a file (e.g. %{home}/privkey.pem) o pass only the password via userdb o inject the path indirectly via static config + userdb variables This works, but is less elegant: protocol imap { crypt_global_private_key user { crypt_private_key_file = %{home}/privkey.pem crypt_private_key_password = %{userdb:private_key_password} } } Again, with the new named filter mechanism, it's no longer possible to directly inject such config values via userdb, which makes fully dynamic per-user key provisioning harder. I now have to export all encrypted private keys from the database to the users home directory. Oemer

4 11

warning: /usr/lib/postfix/sbin/virtual: bad command startup -- throttling
by David Koski 22 May '26

22 May '26

Hello, I have set up a new dovecot mail server using MySQL backend. All users, passwords and related data are in SQL. I'm seeing the following warning in the mail.log file: warning: /usr/lib/postfix/sbin/virtual: bad command startup -- throttling It appears to have no impact on mail delivery. Since paths to user directories are yielded by the SQL database, I'm left wondering why this is even a warning. Regards, David Koski dkoski(a)sutinen.com # 2.4.1-4 (7d8c0e5759): /etc/dovecot/dovecot.conf # Pigeonhole version 2.4.1-4 (0a86619f) # OS: Linux 6.12.69+deb13-amd64 x86_64 Debian 13.5 # Hostname: B914839.online-server.cloud # 4 default setting changes since version 2.4.0 dovecot_config_version = 2.4.0 auth_debug = yes auth_debug_passwords = yes auth_mechanisms = plain login gssapi cram-md5 digest-md5 debug_log_path = /var/log/dovecot/debug.log default_vsz_limit = 512M dovecot_storage_version = 2.4.0 fts_autoindex = yes fts_autoindex_max_recent_msgs = 999 fts_search_add_missing = yes info_log_path = /var/log/dovecot/info.log lda_mailbox_autocreate = yes lda_mailbox_autosubscribe = yes log_debug = category=auth log_path = /var/log/dovecot/dovecot.log mail_driver = maildir mail_plugins { quota = yes } mailbox_directory_name_legacy = no protocols { imap = yes lmtp = yes sieve = yes } quota_exceeded_message = User %{user} has exceeded the storage volume. / User %{user} has exhausted allowed storage space. sieve_plugins { sieve_imapsieve = yes sieve_extprograms = yes } sql_driver = mysql ssl = required namespace inbox { inbox = yes prefix = separator = . type = private mailbox Drafts { auto = subscribe special_use = "\\Drafts" } mailbox Outbox { special_use = "\\Drafts" } mailbox Junk { auto = subscribe special_use = "\\Junk" } mailbox "Junk Email" { auto = no special_use = "\\Junk" } mailbox "Junk E-mail" { auto = no special_use = "\\Junk" } mailbox Trash { auto = subscribe special_use = "\\Trash" } mailbox "Deleted Items" { auto = no special_use = "\\Trash" } mailbox Spam { auto = no special_use = "\\Junk" } mailbox Archives { auto = no special_use = "\\Archive" } mailbox Sent { auto = subscribe special_use = "\\Sent" } mailbox "Sent Items" { auto = no special_use = "\\Sent" } mailbox "Sent Messages" { auto = no special_use = "\\Sent" } } service imap-login { inet_listener imap { } inet_listener imaps { } } service pop3-login { inet_listener pop3 { } inet_listener pop3s { } } service submission-login { inet_listener submission { } inet_listener submissions { } } service lmtp { unix_listener /var/spool/postfix/private/dovecot-lmtp { group = postfix mode = 0600 user = postfix } } service imap { } service pop3 { } service submission { } service auth { unix_listener auth-userdb { group = postfix } unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0660 user = postfix } } service auth-worker { } service dict { unix_listener dict { } } ssl_server { cert_file = /etc/letsencrypt/live/mail.sutinen.com/fullchain.pem key_file = /etc/letsencrypt/live/mail.sutinen.com/privkey.pem } protocol lda { mail_plugins { sieve = yes quota = yes } } protocol imap { mail_plugins { imap_sieve = yes } } protocol lmtp { mail_plugins { quota = yes sieve = yes notify = yes push_notification = yes } postmaster_address = postmaster(a)sutinen.com } service managesieve-login { inet_listener sieve { port = 4190 } inet_listener sieve_deprecated { port = 2000 } } service managesieve { } sieve_script personal { active_path = /var/vmail/sieve/%{user | domain }/%{user | username }/active-script.sieve driver = file path = /var/vmail/sieve/%{user | domain }/%{user | username }/scripts type = personal } sieve_script spam-global { path = /var/vmail/sieve/global/spam-global.sieve type = before } mailbox Spam { sieve_script spam { cause = copy path = /var/vmail/sieve/global/learn-spam.sieve type = before } } imapsieve_from Spam { sieve_script ham { cause = copy path = /var/vmail/sieve/global/learn-ham.sieve type = before } } mysql /var/run/mysqld/mysqld.sock { dbname = vmail password = # hidden, use -P to show it user = vmail } passdb sql { driver = sql query = CALL password_query('%{user}', '%{password}') } userdb sql { driver = sql query = CALL user_query_dovecot('%{user | username}', '%{user | domain}') }

3 2

Dovecot 2.4 authentication
by David Koski 22 May '26

22 May '26

Hello, I just put a new Postfix with Dovecot 2.4 server on line migrating the email from Dovecot 2.3. I have discovered a number of clients (all copiers so far) that no longer authenticate SMTP. Mechanisms configured: auth_mechanisms = plain login gssapi cram-md5 digest-md5 I found that if I disable all encrypted password methods (some copiers list them separately with a checkbox) and leave only plain/login on the client side, then it succeeds. But sometimes it is not necessary. It's almost as if it only tries once and gives up if it fails. I'm not sure how it is actually supposed to work. But it worked with Dovecot 2.3. I did test one account with an encrypted password like "{CRAM-MD5}6e3..." successfully. But other accounts failed. It almost looks like the encryption method must be specified on the client side to match the server before it will work consistently. I know that password encryption is unnecessary with STARTTLS but I have to live with it now. I have noticed that Thunderbird configured with encryption silently falls back to plain/login so I didn't notice a problem. Regards, David Koski dkoski(a)sutinen.com

2 4