October 2019 - dovecot

encrypt incoming emails with public gpg key before they are stored to maildir
by Fourhundred Thecat 31 Oct '19

31 Oct '19

Hello, I have asked on the postfix mailing list for a solution, how to encrypt incoming emails with public gpg key My original idea was to use a smtpd-milter, which would encrypt all incoming plaintext messages of given user, using the users public gpg key. This way, it would look as if the original sender has sent the message encrypted. Somebody suggested this might be better done in Dovecot, as it is Dovecot who stores the emails in Maildir. Does anybody have any suggestions how to implement this scheme in Dovecot ? I am including the original email below: > when new email arrives, and it is not already encrypted, I would like to > run it through a filter, which would encrypt the message with my public > gpg key, as if the original sender has sent the email encrypted. > > Why do I want to do this ? Why not ask the sender to send encrypted > messages to start with ? > > Lets say my bank sends me emails. I cannot force my bank to use gpg > encryption. I am happy they use email at all, instead of paper mail. > > My email server is untrusted. It can be hacked into and emails stolen. > Full disk encryption will not help, because the disk must be decrypted > during runtime. > > With my scheme, all emails would be stored encrypted on my server, and > decryption key does not exist on the server (emails are decrypted on my > local client) > > What would be the best way to implement this ? > > Can such filter work, without ever storing plaintext email on disk ? thanks,

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Dovecot HSM
by Júlio Covolato 31 Oct '19

31 Oct '19

Hi. I'm looking for a tutorial/how-to for a HSM (Hierarchical /Storage/ Management). keeping old messages for a user in a cheap storage and recent messages in a faster one. I see on dovecot2 wiki an alternative for hsm as "Alternate storage", but I don't now if it's a good solution for me. The expected result is a faster imap/pop access for new messages on a "heavy mail users" mailbox, and obviously low cost! Thanks in advance. -- ---------------------------------- _ Engº Julio Cesar Covolato 0v0 <julio(a)psi.com.br> /(_)\ F: +55 11 99175-9260 ^ ^ PSI INTERNET ----------------------------------

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Re: Dovecot HSM
by Marc Roos 30 Oct '19

30 Oct '19

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How do I search for "greetings of the day"
by Ralf Hildebrandt 30 Oct '19

30 Oct '19

My users say that "greetings of the day" occurs in academic spam a lot. Since I don't trust my users, I opted to verify this bold claim. But how do I search for a sequence of multiple words? doveadm import -u restore(a)backup.invalid mdbox:/home/copymail/mdbox "" mailbox INBOX BODY "Greetings of the day" doveadm import -u restore(a)backup.invalid mdbox:/home/copymail/mdbox "" mailbox INBOX TEXT "Greetings of the day" (what's the difference betweeen BODY and TEXT?) Is it even possible, given that "the" and "of" are probably stop words? -- Ralf Hildebrandt Geschäftsbereich IT | Abteilung Netzwerk Charité - Universitätsmedizin Berlin Campus Benjamin Franklin Hindenburgdamm 30 | D-12203 Berlin Tel. +49 30 450 570 155 | Fax: +49 30 450 570 962 ralf.hildebrandt(a)charite.de | https://www.charite.de

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Recovering emails from "dead" server
by Mark | Small World Systems 29 Oct '19

29 Oct '19

I have a Linix server that won't boot. I've patched in a live CD and mounted the original HDDs so I can browse the files using SSH. I am trying to find where all my customer emails are stored so that I can (hopefully) copy them off this "dead" server onto a new server which is also running cPanel and Dovecot. Does anyone know where Dovecot stores emails for each email account when it runs under cPanel? I can see a directory called /home/<cpanel username>/mail/<domain name>/<mail username> (I've used <xxxxx> in place of the actual text to obviscate the actual user information). If I navigate to that directory I can see lots of interesting sub directories e.g. cur, new and tmp plus some files such as: dovecot.index.cache, dovecote.index, dovecote-uidlist But then I'm stumped. I was hoping to find a big fat directory that contained all the mail files. Is anyone able to tell me what I need to copy across to get all the old emails off the "dead" server onto the new one? Thank you.

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Sieve problem - Timeout while waiting for lock
by Domenico Pastore 29 Oct '19

29 Oct '19

Hi, I have an issue with dovecot 2.3.7.2. When lmtp stores a message into INBOX, I get this error: 2019-10-29 16:32:53 lmtp(“test@XXXX”)<28874><4IPiEytbuF3KcAAAioI89A>: Error: sieve: Execution of script /config/dovecot/common/default.sieve was aborted due to temporary failure 2019-10-29 16:32:53 lmtp(“test@XXXX”)<23470>: Error: sieve: msgid=CE595339-2976-6DFD-FDAD-EEA15CC53218@XXXX: failed to store into mailbox ‘INBOX’: Timeout while waiting for lock This problem only occurs for one mailbox and when it receives a big amount of messages. With the previous version (dovecot 2.2.15) this did never occur. The file /config/dovecot/common/default.sieve is in local server, no on NFS filesystem BR, Domenico ----------------- # 2.3.7.2 (3c910f64b): /config/dovecot/dovecot/dovecot.conf # Pigeonhole version 0.5.7.2 (7372921a) # OS: Linux 3.10.0-1062.1.2.el7.x86_64 x86_64 CentOS Linux release 7.7.1908 (Core) auth_debug = yes auth_master_user_separator = * auth_username_format = base_dir = /data/dovecot/var/run/dovecot default_client_limit = 8192 default_vsz_limit = 768 M dict { sqlquota = mysql:/config/dovecot/common/dovecot-dict-sql.conf.ext } disable_plaintext_auth = no doveadm_password = # hidden, use -P to show it first_valid_gid = 101 first_valid_uid = 102 imap_id_send = import_environment = TZ info_log_path = /LOGS/dovecot/dovecot.log instance_name = dovecot listen = dovecot log_path = /LOGS/dovecot/dovecot.log log_timestamp = "%Y-%m-%d %H:%M:%S " mail_gid = 101 mail_location = maildir:%h/Maildir mail_max_userip_connections = 50 mail_plugins = quota fts fts_solr mail_log notify virtual mail_uid = 102 maildir_broken_filename_sizes = yes 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 vnd.dovecot.debug mbox_write_locks = fcntl namespace { hidden = yes list = no location = virtual:/config/dovecot/common/virtual:INDEX=~/virtual:SUBSCRIPTIONS=.subscriptions/%u prefix = Messaggi in arrivo. separator = . subscriptions = no } 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 = INBOX. separator = . subscriptions = yes type = private } passdb { args = /config/dovecot/common/passwd.masterusers driver = passwd-file master = yes } passdb { args = /config/dovecot/dovecot/dovecot-ldap.conf driver = ldap } passdb { args = /config/dovecot/common/dovecot-ldap-multiuser.conf driver = ldap master = yes } passdb { args = /config/dovecot/common/dovecot-ldap-webmail.conf.ext driver = ldap master = yes } plugin { fts = solr fts_autoindex = yes fts_autoindex_max_recent = 1000 fts_solr = url=https://192.160.10.81:8983/solr/dovecot/ mail_log_events = delete undelete expunge copy mailbox_delete mailbox_rename flag_change save mailbox_create mail_log_fields = uid box msgid size flags quota = dict:User quota::proxy::sqlquota quota_rule2 = INBOX.Trash:storage=+100M sieve_default = /dovecot/common/default.sieve sieve_extensions = +vnd.dovecot.debug } postmaster_address = posta(a)XXXX.it service anvil { client_limit = 8000 } service auth { client_limit = 12000 unix_listener auth-userdb { mode = 0600 } } service dict { process_limit = 7500 process_min_avail = 10 unix_listener dict { mode = 0600 user = dovecot } } service doveadm { chroot = client_limit = 1 drop_priv_before_exec = no executable = doveadm-server extra_groups = group = idle_kill = 0 inet_listener { port = 924 } privileged_group = process_limit = 0 process_min_avail = 10 protocol = service_count = 100 type = unix_listener doveadm-server { group = mode = 0600 user = } user = vsz_limit = 18446744073709551615 B } service imap-login { inet_listener imap { port = 143 } inet_listener imaps { port = 993 ssl = yes } process_limit = 5000 process_min_avail = 10 } service imap { drop_priv_before_exec = yes process_limit = 5000 process_min_avail = 10 } service lmtp { inet_listener lmtp { port = 24 } process_limit = 2500 process_min_avail = 10 } service managesieve-login { inet_listener sieve { port = 4190 } process_min_avail = 0 service_count = 1 vsz_limit = 64 M } service managesieve { drop_priv_before_exec = yes process_limit = 1024 } service pop3-login { inet_listener pop3 { port = 110 } inet_listener pop3s { port = 995 ssl = yes } process_limit = 1000 process_min_avail = 5 } service pop3 { drop_priv_before_exec = yes process_limit = 1000 process_min_avail = 5 } ssl_cert = </config/dovecot/common/certs/dovecot.pem ssl_client_ca_file = /config/solr-certs/solr-ssl.pem ssl_key = # hidden, use -P to show it userdb { args = /config/dovecot/dovecot/dovecot-ldap.conf driver = ldap } protocol lmtp { mail_plugins = quota mail_log notify sieve virtual fts fts_solr } protocol lda { mail_plugins = quota mail_log notify sieve virtual } protocol imap { mail_plugins = quota imap_quota mail_log notify virtual fts fts_solr } protocol pop3 { mail_plugins = quota mail_log notify virtual pop3_uidl_format = UID%u-%v }

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Error: Mailbox INBOX: Broken file dovecot-uidlist: Invalid data
by Dirk 29 Oct '19

29 Oct '19

Hi list, today a user reported messages are disappearing from his INBOX and I discovered a two digit number of mailboxes with broken dovecot-uidlist files. The log says: Oct 29 08:51:34 mail02 dovecot: lmtp(info(a)example.com)<5270><QOoVJIbvt12WFAAAJOVBUw>: Error: Mailbox INBOX: Broken file /var/vmail/example.com/info/dovecot-uidlist line 88: Invalid data: And the respective files do look broken: 4596 :1572344253.M529133P14861.mail03.example.com,S=53053,W=54233 ^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@4597 :1572344797.M93833P15905.mail03.example.com,S=126866,W=129256 Setup : Behind a director I am running two dovecot backend servers sharing the vmail directory via NFS. Do you have an idea where this might come from? How can I debug this further? Cheers, Dirk

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changing cipher for imap clients
by Fourhundred Thecat 29 Oct '19

29 Oct '19

When my client connects, I see this in my log: dovecot: imap-login: TLSv1 with cipher ECDHE-RSA-AES128-SHA (128/128 bits) Whereas, when client connects to my postfix server, I see: Anonymous TLS connection established from * TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits) how can I tell dovecot to use AES256, instead of AES128 ? is this set by ssl_cipher_list ? Here are my current values (defaults) # doveconf ssl_cipher_list ssl_cipher_list = ALL:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@STRENGTH # dovecot --version 2.3.4.1 thanks,

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Dovecot and MySQL aborted connections.
by Reio Remma 28 Oct '19

28 Oct '19

Is anyone else using Dovecot (2.3.8) with MySQL (5.7) seeing a lot of these in MySQL logs? 2019-10-28T11:08:20.384428+02:00 58378 [Note] Aborted connection 58378 to db: 'vmail' user: 'vmail' host: 'localhost' (Got an error reading communication packets) 2019-10-28T11:10:09.821171+02:00 58420 [Note] Aborted connection 58420 to db: 'vmail' user: 'vmail' host: 'localhost' (Got an error reading communication packets) 2019-10-28T11:11:26.170015+02:00 58441 [Note] Aborted connection 58441 to db: 'vmail' user: 'vmail' host: 'localhost' (Got an error reading communication packets) 2019-10-28T11:13:14.091426+02:00 58459 [Note] Aborted connection 58459 to db: 'vmail' user: 'vmail' host: 'localhost' (Got an error reading communication packets) They've plagued my logs for as long as I can remember. Is Dovecot not closing connections to the database properly or something similar? Reio

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Dovecot list breaks DKIM.
by Reio Remma 28 Oct '19

28 Oct '19

Hello again, I noticed mails from the Dovecot list break DKIM signatures. Perhaps it's something to look at? Most lists I'm on manage to pass messages with DKIM intact. Authentication-Results: abc.abc.abc; dkim=fail (rsa verify failed) header.d=mrstuudio.ee header.s=mr header.b=M03Fp5lE; dmarc=pass (policy=none) header.from=dovecot.org; spf=pass Thanks, Reio

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