June 2021 - dovecot - dovecot.org

Dovecot mailing list and DKIM
by Kevin N. 28 Jun '21

28 Jun '21

Hello everybody, Going through my mail logs I noticed that a couple of messages from the Dovecot mailing list failed DKIM validation. For example, this one has failed: https://markmail.org/message/te7tycmpiutw4kia 'opendkim-testkey' shows that the key is OK. The messages in the example comes from yahoo.com, however other messages from yahoo.com, ones that are not sent through the mailing list, are properly validated. The failure is not specific to yahoo.com since a couple of other messages from other domains, sent though the mailing list, also failed DKIM validation. However, the vast majority of the messages from the list properly pass DKIM validation. From what I have read, mailing lists in general do not play very well with DKIM or SPF and the Dovecot mailing list also had some issues with this in the past. With the Dovecot mailing list, I am a bit curious about why the vast majority of the messages from the list pass DKIM validation while a couple of them fail. Does the Dovecot mailing list software alter the message in a way that causes the failure? Or is there something else going on? Any thoughts? Cheers.

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ZLIB/ZSTD Compressed MBOX in Maildir++ layout
by Pedro Ribeiro 28 Jun '21

28 Jun '21

Hello everyone! Our archive namespace is kept in MBOX format with Maildir++ layout due to: * Need to have the email from all users/folders self contained (our base namespace uses MDBOX with single instance storage of attachments) * MBOX/FS layout isn't supported because some folders have messages and subfolders. I'm trying to compress that namespace using zstd/gzip following the informations from Dovecot documentation about the zlib plugin but when the (MBOX/Maildir++) compress and become with .zst/.zstd/.gz suffix (both tested) the system can't read the mailboxes and incorrectly reports the suffix (.zstd/.gz) as a subfolder name (following the Maildir++ file structure). Is there any way to make the MBOX/Maildir++ compatible with the zlib compression? Using Dovecot 2.3.14 on Debian10 Regards. -- Best regards, =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= Pedro Ribeiro Politécnico de Lisboa, Serviços da Presidência Departamento de Sistemas de Informação e Comunicações Phone: +351 210 464 700 (general) / VoIP: 80100 Helpdesk: helpdesk(a)net.ipl.pt / https://www.net.ipl.pt =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

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Problem with Lua notification script since 2.3.15 update
by Ralf Becker 28 Jun '21

28 Jun '21

If the Lua-notifications are enabled, Dovecot imap dies immediately at authentication: Jun 28 09:17:29 imap-login: Info: Login: user=<ralf>, method=PLAIN, rip=172.18.0.12, lip=172.18.0.16, mpid=16, TLS, session=<dDhm9c/FYtqsEgAM> Jun 28 09:17:29 imap(ralf)<16><dDhm9c/FYtqsEgAM>: Panic: file dlua-script.c: line 224 (dlua_script_init): assertion failed: (lua_gettop(script->L) == 0) Jun 28 09:17:29 imap(ralf)<16><dDhm9c/FYtqsEgAM>: Error: Raw backtrace: /usr/lib/dovecot/libdovecot.so.0(backtrace_append+0x41) [0x7f9f537ca5c1] -> /usr/lib/dovecot/libdovecot.so.0(backtrace_get+0x22) [0x7f9f537ca6e2] -> /usr/lib/dovecot/libdovecot.so.0(+0x1070bb) [0x7f9f537d70bb] -> /usr/lib/dovecot/libdovecot.so.0(+0x107157) [0x7f9f537d7157] -> /usr/lib/dovecot/libdovecot.so.0(+0x5bb2b) [0x7f9f5372bb2b] -> /usr/lib/dovecot/libdovecot-lua.so.0(+0x5354) [0x7f9f53311354] -> /usr/lib/dovecot/modules/lib22_push_notification_lua_plugin.so(+0x3842) [0x7f9f532c6842] -> /usr/lib/dovecot/modules/lib20_push_notification_plugin.so(push_notification_driver_init+0x19c) [0x7f9f532d062c] -> /usr/lib/dovecot/modules/lib20_push_notification_plugin.so(+0x846f) [0x7f9f532d246f] -> /usr/lib/dovecot/modules/lib20_push_notification_plugin.so(+0x8b6a) [0x7f9f532d2b6a] -> /usr/lib/dovecot/libdovecot-storage.so.0(hook_mail_user_created+0x211) [0x7f9f539084e1] -> /usr/lib/dovecot/libdovecot-storage.so.0(mail_user_init+0x20b) [0x7f9f5390e80b] -> /usr/lib/dovecot/libdovecot-storage.so.0(mail_storage_service_next_with_session_suffix+0x587) [0x7f9f5390bd57] -> /usr/lib/dovecot/libdovecot-storage.so.0(mail_storage_service_lookup_next+0x53) [0x7f9f5390c4c3] -> dovecot/imap(client_create_from_input+0x180) [0x5626eb18fe40] -> dovecot/imap(+0x3112a) [0x5626eb19012a] -> /usr/lib/dovecot/libdovecot.so.0(+0x8d60e) [0x7f9f5375d60e] -> /usr/lib/dovecot/libdovecot.so.0(+0x8d97b) [0x7f9f5375d97b] -> /usr/lib/dovecot/libdovecot.so.0(+0x8e8be) [0x7f9f5375e8be] -> /usr/lib/dovecot/libdovecot.so.0(connection_input_default+0x15e) [0x7f9f537cef5e] -> /usr/lib/dovecot/libdovecot.so.0(io_loop_call_io+0x6d) [0x7f9f537ed3ed] -> /usr/lib/dovecot/libdovecot.so.0(io_loop_handler_run_internal+0x145) [0x7f9f537eea15] -> /usr/lib/dovecot/libdovecot.so.0(io_loop_handler_run+0x54) [0x7f9f537ed494] -> /usr/lib/dovecot/libdovecot.so.0(io_loop_run+0x40) [0x7f9f537ed600] -> /usr/lib/dovecot/libdovecot.so.0(master_service_run+0x17) [0x7f9f537609e7] -> dovecot/imap(main+0x469) [0x5626eb172c19] -> /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xf3) [0x7f9f535020b3] -> dovecot/imap(_start+0x2e) [0x5626eb172cae] Jun 28 09:17:29 imap(ralf)<16><dDhm9c/FYtqsEgAM>: Fatal: master: service(imap): child 16 killed with signal 6 (core dumps disabled - https://dovecot.org/bugreport.html#coredumps) I use the following Dovecot configuration: # Store METADATA information in a file dovecot-metadata in user's home mail_attribute_dict = file:%h/dovecot-metadata # enable metadata protocol imap { imap_metadata = yes } # add necessary plugins for Lua push notifications mail_plugins = $mail_plugins mail_lua notify push_notification push_notification_lua # Lua notification script and URL of EGroupware push server plugin { push_notification_driver = lua:file=/etc/dovecot/dovecot-push.lua push_lua_url = https://Bearer:secret@boulder.egroupware.org/egroupware/push } The Lua script is available under https://github.com/EGroupware/swoolepush/blob/master/doc/dovecot-push.lua The whole Dovecot configurations is available under https://github.com/EGroupware/build.opensuse.org/tree/master/server:eGroupW… Dovecot runs in a Ubuntu 20.04 based container and seems to use the correct liblua5.3: root@750978e5c0ee:/# dpkg -l|grep -i lua ii dovecot-lua 2:2.3.15-1+ubuntu20.04 amd64 secure POP3/IMAP server - LUA support ii liblua5.3-0:amd64 5.3.3-1.1ubuntu2 amd64 Shared library for the Lua interpreter version 5.3 ii lua-json 1.3.4-2 all JSON decoder/encoder for Lua ii lua-lpeg:amd64 1.0.2-1 amd64 LPeg library for the Lua language ii lua-socket:amd64 3.0~rc1+git+ac3201d-4 amd64 TCP/UDP socket library for the Lua language Everything was running fine with 2.3.13, have not tried with 2.3.14 yet. Any ideas? Ralf -- Ralf Becker EGroupware GmbH [www.egroupware.org] Handelsregister HRB Kaiserslautern 3587 Geschäftsführer Birgit und Ralf Becker Leibnizstr. 17, 67663 Kaiserslautern, Germany Telefon +49 631 31657-0

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[BUG] doveadm / mail-crypt: Error when setting new password for a user key
by Kevin N. 28 Jun '21

28 Jun '21

Dovecot version: 2.3.14 When setting a new password for a user key you have the option to prompt the user for the old and the new password, instead of providing them as parameters (using -N and -O instead of -n and -o). However, running: doveadm mailbox cryptokey password -u user@domain -N -O produces an error instead of prompting the user for the old and the new password. The error is: password: option requires an argument -- 'O' You can work around this by providing a dummy input for -O which seems to be properly ignored in the end, but it would be nice to not throw any errors since -O should not expect an argument. Regards.

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Support client_id variable expansion
by Eirik Rye 28 Jun '21

28 Jun '21

Hello, We are using imap_id_log='*' (and imap_id_retain=yes) to log user client information to the dovecot logs, and this information is aggregated to give us extra debugging information for customer support. However, as some clients send the ID information pre-login and others send it post-login, the aggregation logic is needlessly complex as we need to correlate the session IDs of the pre-login ID messages in order to determine the correct user. Hoping to simplify this, I wanted to log the client_id variable on logout, in imap_logout_format: imap_logout_format = in=%i out=%o deleted=%{deleted} expunged=%{expunged} trashed=%{trashed} hdr_count=%{fetch_hdr_count} hdr_bytes=%{fetch_hdr_bytes} body_count=%{fetch_body_count} body_bytes=%{fetch_body_bytes} client_id="%{client_id}" However, this only results in the following log being printed: client_id="UNSUPPORTED_VARIABLE_client_id" While examining the source code (login-common/client-common.c), it seems like this could be trivially supported by adding `client_id` to the `login_var_expand_empty_tab` struct, and adding the relevant code to populate this variable to `get_var_expand_table(struct client *client)`. I am willing to write a pull request for this, unless I am missing some obvious reason why expansion of the client's `client_id` field is not supported in the first place? - Eirik

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Re: [Dovecot-news] Dovecot v2.3.15 released
by Daniel J. Luke 28 Jun '21

28 Jun '21

On Jun 21, 2021, at 7:20 AM, Timo Sirainen <timo(a)sirainen.com> wrote: > Here's a new release with some security fixes and quite a lot of other changes as well. > > * Removed support for Lua 5.2. Use version 5.1 or 5.3 instead. Looks like it doesn't want to build w/o lua now. On my MacOS system configure says: checking whether we will be linking in Lua... no ... but after fixing the implicit i_gettimeofday declaration, build fails with: /bin/sh ../../libtool --tag=CC --mode=link gcc -std=gnu99 -g -O2 -fstack-protector-strong -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 -Wall -W -Wmissing-prototypes -Wmissing-declarations -Wpointer-arith -Wchar-subscripts -Wformat=2 -Wbad-function-cast -Wno-duplicate-decl-specifier -Wstrict-aliasing=2 -I/opt/local/include -no-undefined -L/opt/local/lib -o libdict_lua.la libtool: link: ar cru .libs/libdict_lua.a ar: no archive members specified (this doesn't happen with 2.3.14.1) -- Daniel J. Luke

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Backing up per user keys for mailcrypt
by Ben Burk 28 Jun '21

28 Jun '21

I am wondering how I can back up keys for mail users in their password-protected form, without exporting them from `doveadm mailbox cryptokey export`, which requires a password. The goal here is to perform routine backups to keep keys current. Relevant config is as follows: mail_attribute_dict = file:%h/Maildir/dovecot-attributes mail_plugins = $mail_plugins mail_crypt plugin { mail_crypt_curve = secp521r1 mail_crypt_save_version = 2 mail_crypt_require_encrypted_user_key = yes } Am i correct in assuming I should back up the dovecot-attributes file? Are there any ancillary files that need to be backed up as well, such as indexes, to properly read and handle this file? I have viewed the file and it appears there are several keys at play for a single mail user. Do different folders in a users imap space have different encryption keys? Are all of these keys populated in this dovecot-attributes file? Is there any established procedure for restoring keys? Is it as simple as placing the dovecot-attributes file, if that is infact what needs to be backed up beforehand to perform a restore. -- Ben Burk BURK.TECH System Administrator

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Python module for HTTP API
by Michael Ströder 28 Jun '21

28 Jun '21

HI! Can anybody recommend a high-level Python module for accessing doveadm's HTTP API? [1] Ciao, Michael. [1] https://doc.dovecot.org/admin_manual/doveadm_http_api/

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Quota Config With Prefetch Creating Alias Directories
by dovecot＠ptld.com 27 Jun '21

27 Jun '21

Using Dovecot 2.3.8 with Postfix & MySQL on Centos. I have a sql table with account info, email addresses, password, quotas, etc I have another sql table for aliases containing which alias points to what email address. For imap access im using passdb password_query with prefetch. I setup quotas using count and configured postfix to check quotas with check_policy_service before accepting email. Discovered that it wont lookup quotas using prefetch. Added a second userdb so quota request can use user_query instead of the imap password_query prefetch version. userdb { driver = sql args = /etc/dovecot/mysql_quota.include skip = found result_success = return-ok result_failure = return-ok } This worked for existing email addresses in the accounts table. But any email sent to an alias was rejected because user not found. Not by postfix, postfix can see its an alias, but when postfix does check_policy_service dovecot issued the rejection because its not finding the alias in the accounts table per the userdb user_query. I added "result_failure = return-ok" to the userdb so if user_query doesn't find the address postfix is asking to accept mail for, it will fall back on quota default values. Then dovecot isn't forcing the mail to be rejected and postfix knows if its a valid user or alias. This seems to solve the issue, dovecot will return per user quotas or if not found then the global quota and let postfix decided whats a valid address to accept or reject. But now there is a side effect. Every time you ask dovecot for a quota, and if its a first time use of a newly created account dovecot creates the index directories and index files on disk. Because im using result_failure=return-ok which tells dovecot the user was found to prevent aliases from being rejected, dovecot is also creating directories and indexes for those aliases postfix is sending over check_policy_service. First question: Is this the best way to configure dovecot using quota verification for postfix to work will aliases? Second question: How can i prevent directories and indexes being created for non found user (aliases) accounts? Thank you.

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Dovecot v2.3.14.1 released
by Timo Sirainen 24 Jun '21

24 Jun '21

Hi, This is an "important fixes only" release in case you don't want to upgrade to v2.3.15. There is no matching Pigeonhole release - use the same v2.3.14 instead. https://dovecot.org/releases/2.3/dovecot-2.3.14.1.tar.gz <https://dovecot.org/releases/2.3/dovecot-2.3.14.1.tar.gz> https://dovecot.org/releases/2.3/dovecot-2.3.14.1.tar.gz.sig <https://dovecot.org/releases/2.3/dovecot-2.3.14.1.tar.gz.sig> Binary packages in https://repo.dovecot.org/ <https://repo.dovecot.org/> Docker images in https://hub.docker.com/r/dovecot/dovecot <https://hub.docker.com/r/dovecot/dovecot> * CVE-2021-29157: Dovecot does not correctly escape kid and azp fields in JWT tokens. This may be used to supply attacker controlled keys to validate tokens, if attacker has local access. * CVE-2021-33515: On-path attacker could have injected plaintext commands before STARTTLS negotiation that would be executed after STARTTLS finished with the client. - lib-index: Corrupted mime.parts in dovecot.index.cache may have resulted in Panic: file imap-bodystructure.c: line 206 (part_write_body): assertion failed: (text == ((part->flags & MESSAGE_PART_FLAG_TEXT) != 0)) - imap: SETMETADATA could not be used to unset metadata values. Instead NIL was handled as a "NIL" string. v2.3.14 regression.

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