May 2016 - dovecot - dovecot.org

Reappearing emails
by Ron Cleven 17 Jan '17

17 Jan '17

We have been running Dovecot 2.2.10 with a pair of CentOS 7 boxes with replications for the past year. We have been quite happy with the performance and reliability. Recently we received a report from an Android IMAP user that emails that he deleted without reading would often reappear in his INBOX. At first I thought it might be some quirky incompatibility with his email client, but I found that I could easily reproduce it in Roundcube by dragging an unread email to Trash. I have been monitoring this forum fairly religiously and don't recall seeing any similar reports. I plan to capture the IMAP wire interactions, but before doing that, I thought I would submit this to the IMAP gods to see if anyone had heard of this and/or if there is some newer version that might resolve the problem. This particular customer contacted his email vendor and asked them to analyze the problem. The actual log data is gigantic, so I just pasted in the vendor's narrative below in case it helps. Otherwise, as I said, I will capture a similar interaction at the wire level and follow up here. Vendor's narrative: You had 8 messages in the Inbox, and moved two to Trash. The server notified the app on the push connection (for Inbox) that there are now 6 messages. By the time the app got around to catch up with that (it did the Trash folder first), the server said "oh wait, there are 8 messages, not 6" (in the Inbox), and so the app synced them in, just as reported. app selecting the Inbox, server saying there are 8 messages there app moving UID 729 and 730 to Trash (push) server saying Trash now has 34 messages (push) server saying two messages gone from Inbox, 6 left (push) 6 messages left in Inbox becoming 8 (push) and here they are (the two new ones) Thanks, Ron

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logging TLS SNI hostname
by Arkadiusz Miśkiewicz 08 Nov '16

08 Nov '16

Is there a way to log SNI hostname used in TLS session? Info is there in SSL_CTX_set_tlsext_servername_callback, dovecot copies it to ssl_io->host. Unfortunately I don't see it expanded to any variables ( http://wiki.dovecot.org/Variables ). Please consider this to be a feature request. The goal is to be able to see which hostname client used like: May 30 08:21:19 xxx dovecot: pop3-login: Login: user=<abc>, method=PLAIN, rip=1.1.1.1, lip=2.2.2.2, mpid=17135, TLS, SNI=pop3.somehost.org, session=<hfS9Qwk03sBTBnrN> -- Arkadiusz Miśkiewicz, arekm / ( maven.pl | pld-linux.org )

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imapc fetch optimization
by Nagy, Attila 27 Sep '16

27 Sep '16

Hi, imapc does a lot of UID FETCH $UID (BODY.PEEK[]), which is nice, because it works even with the dumbest IMAP server, altough it really kills performance, especially on high latency lines. I wonder: if IMAP servers can effectively handle boundless fetches (like a list with all wanted UIDs, or simply 1:* if all are needed), do you see this as a good addition to develop? This could be a new imapc_features setting afterall... Thanks,

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[Dovecot] Plugins: virtuals vs acls
by Leho Kraav 20 Sep '16

20 Sep '16

Hi all dovecot-virtual: * all when dovecot-acl files restrict some subset of * for a user, does dovecot respect these ACLs when collecting messages for virtual folder? I'd like a confirmation about what I should be seeing when I start implementing this setup.

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Error: istream-seekable: safe_mkstemp(/tmp/dovecot.imap.) failed
by Thomas Leuxner 05 Sep '16

05 Sep '16

I'm seeing these recently: Feb 27 09:24:01 nihlus dovecot: imap(tlx(a)leuxner.net): Error: istream-seekable: safe_mkstemp(/tmp/dovecot.imap.) failed: No such file or directory Feb 27 09:24:01 nihlus dovecot: imap(tlx(a)leuxner.net): Error: istream-seekable: safe_mkstemp(/tmp/dovecot.imap.) failed: No such file or directory Feb 27 09:24:01 nihlus dovecot: imap(tlx(a)leuxner.net): Error: istream-seekable: safe_mkstemp(/tmp/dovecot.imap.) failed: No such file or directory Feb 27 09:24:01 nihlus dovecot: imap(tlx(a)leuxner.net): Error: istream-seekable: safe_mkstemp(/tmp/dovecot.imap.) failed: No such file or directory Feb 27 09:24:01 nihlus dovecot: imap(tlx(a)leuxner.net): Error: istream-seekable: safe_mkstemp(/tmp/dovecot.imap.) failed: No such file or directory Feb 27 09:24:01 nihlus dovecot: imap(tlx(a)leuxner.net): Error: istream-seekable: safe_mkstemp(/tmp/dovecot.imap.) failed: No such file or directory $ doveconf -n | head # 2.2.devel (f1a9b58): /etc/dovecot/dovecot.conf # Pigeonhole version 0.4.devel (0de2a19) Regards Thomas

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ACL List uses wrong namespace for permissions
by Harald Leithner 31 Aug '16

31 Aug '16

Hi, I'm using dovecot 2.2.devel (11c704a) with lazyexpunge and shared Mailboxes, this seams to work since the latest patch. There is only one problem creating the correct dovecot-acl-list, if I login as the normal user that has set permissions for another user everything is ok. If I login with the same user but with a modified roundcube that uses the #EXPUNGED Namespace as root, dovecot overrides the correct dovecot-acl-list with an empty version. I think this is the most interesting part of the log: 2016-04-26T16:49:26+02:00 mailstore1 dovecot: imap(user(a)company.at): Debug: fs: root=/srv/storage1/vmail/company/628, index=, indexpvt=, control=, inbox=, alt= 2016-04-26T16:49:26+02:00 mailstore1 dovecot: imap(user(a)company.at): Debug: acl: initializing backend with data: vfile 2016-04-26T16:49:26+02:00 mailstore1 dovecot: imap(user(a)company.at): Debug: acl: acl username = user(a)company.at 2016-04-26T16:49:26+02:00 mailstore1 dovecot: imap(user(a)company.at): Debug: acl: owner = 1 2016-04-26T16:49:26+02:00 mailstore1 dovecot: imap(user(a)company.at): Debug: acl vfile: Global ACLs disabled 2016-04-26T16:49:26+02:00 mailstore1 dovecot: imap(user(a)company.at): Debug: Namespace : type=private, prefix=#EXPUNGED/, sep=, inbox=no, hidden=yes, list=no, subscriptions=no location=mdbox:/srv/storage1/vmail/company/628:MAILBOXDIR=expunged 2016-04-26T16:49:26+02:00 mailstore1 dovecot: imap(user(a)company.at): Debug: fs: root=/srv/storage1/vmail/company/628, index=, indexpvt=, control=, inbox=, alt= 2016-04-26T16:49:26+02:00 mailstore1 dovecot: imap(user(a)company.at): Debug: acl: initializing backend with data: vfile 2016-04-26T16:49:26+02:00 mailstore1 dovecot: imap(user(a)company.at): Debug: acl: acl username = user(a)company.at 2016-04-26T16:49:26+02:00 mailstore1 dovecot: imap(user(a)company.at): Debug: acl: owner = 1 2016-04-26T16:49:26+02:00 mailstore1 dovecot: imap(user(a)company.at): Debug: acl vfile: Global ACLs disabled 2016-04-26T16:49:26+02:00 mailstore1 dovecot: imap(user(a)company.at): Debug: Namespace : type=shared, prefix=#Users/%u/, sep=/, inbox=no, hidden=no, list=children, subscriptions=yes location=mdbox:/srv/storage1/vmail%h 2016-04-26T16:49:26+02:00 mailstore1 dovecot: imap(user(a)company.at): Debug: shared: root=/var/run/dovecot, index=, indexpvt=, control=, inbox=, alt= 2016-04-26T16:49:26+02:00 mailstore1 dovecot: imap(user(a)company.at): Debug: acl vfile: file /srv/storage1/vmail/company/628/mailboxes/dovecot-acl not found 2016-04-26T16:49:26+02:00 mailstore1 dovecot: imap(user(a)company.at): Debug: Namespace : Using permissions from /srv/storage1/vmail/company/628: mode=0700 gid=default 2016-04-26T16:49:26+02:00 mailstore1 dovecot: imap(user(a)company.at): Debug: acl vfile: file /srv/storage1/vmail/company/628/mailboxes/Drafts/dbox-Mails/dovecot-acl not found 2016-04-26T16:49:26+02:00 mailstore1 dovecot: imap(user(a)company.at): Debug: acl vfile: file /srv/storage1/vmail/company/628/expunged/dovecot-acl not found 2016-04-26T16:49:26+02:00 mailstore1 dovecot: imap(user(a)company.at): Debug: Namespace #EXPUNGED/: Using permissions from /srv/storage1/vmail/company/628: mode=0700 gid=default 2016-04-26T16:49:26+02:00 mailstore1 dovecot: imap(user(a)company.at): Debug: acl vfile: file /srv/storage1/vmail/company/628/expunged/INBOX/dbox-Mails/dovecot-acl not found 2016-04-26T16:49:26+02:00 mailstore1 dovecot: imap(user(a)company.at): Debug: acl vfile: file /srv/storage1/vmail/company/628/expunged/INBOX/test/dbox-Mails/dovecot-acl not found 2016-04-26T16:49:26+02:00 mailstore1 dovecot: imap(user(a)company.at): Debug: acl vfile: reading file /srv/storage1/vmail/company/628/mailboxes/INBOX/dbox-Mails/dovecot-acl 2016-04-26T16:49:26+02:00 mailstore1 dovecot: imap(user(a)company.at): Logged out in=178 out=870 2016-04-26T16:49:26+02:00 mailstore1 dovecot: imap(user(a)company.at): Logged out in=315 out=27172 regards, -- Harald Leithner ITronic Wiedner Hauptstraße 120/5.1, 1050 Wien, Austria Tel: +43-1-545 0 604 Mobil: +43-699-123 78 4 78 Mail: leithner(a)itronic.at | itronic.at

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[Dovecot] How to disable SSL and TLSv1.1?
by Darren Pilgrim 16 Aug '16

16 Aug '16

I'm running Dovecot 2.2.5 and want to make it refuse SSLv2, SSLv3 and TLSv1.0. Clients will opportunistically use TLS 1.1 and 1.2, but now I want require they do so. Is it enough to set ssl_cipher_list = HIGH:!SSLv2:!SSLv3:!TLSv1.0:!aNULL:!MD5 or are there additional settings I need to specify?

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Bug with shared access to mailbox
by van der Kamp, John 15 Aug '16

15 Aug '16

Hello, I'm testing dovecot with some setups, and one of them is with shared mailboxes. The test I wrote will create and delete mail using multiple connections to the same user and folder. Each connection makes a couple of mails, remembers the uid from APPENDUID, and will delete those emails again. At the end of the test I expect an empty folder. This is not what happens. At the end I still have several mails in the folder. I lack insight in the dovecot source to tell exactly what's going on. I've tested this with different setups: 1) local system user, connecting over localhost -> bug is present 2) local system user, connecting over internet -> bug is present, but is harder to reproduce 3) dovecot as proxy to another imap server -> bug is present In step 3, you can even setup a dovecot to be a proxy to another dovecot server. >From logging in the other imap server I've seen that a client command to the proxy like: TAG UID STORE 1:3 +FLAGS (\Deleted) TAG UID EXPUNGE 1:3 will be sent to the other imap server in 3 steps, one for each message. When running the test with multiple threads, that logging shows that some uids are never sent to the other imap server, and some uids are sent over different connections than they original were sent to. (Thread 1 deletes 1:3, Thread 2 deletes 4:6, the proxy of Thread 1 might expunge messages from Thread 2 and vice versa). Attached is a python script which tests the behavior. The script expects a file named "testmail.eml" to upload to the imap server. I used an email which was about 75 kB. I tested using version: 2.2.22 (fe789d2). Let me know if I can help in any other way too. John

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Opportunistic quota recalc
by Tom Sommer 27 Jul '16

27 Jul '16

I'm switching quota backend to redis (from maildir++), so all my current usages are reset. I get that I can do "doveadm quota recalc -A", but it takes forever (and auth processes time out/crash). It would make much more sense to recalc the usage on login if the current usage is unset. Is there no way to do a recalc-quota-on-first-login? Thanks. -- Tom Sommer

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Cannot connect to Dovecot IMAP or POP
by C. Andrews Lavarre 24 Jul '16

24 Jul '16

Hello all. Thank you for your service. Easy when you know how, but presently I do not. After literally months of research and experimentation we simply cannot log into our PAM / apache2 / postfix / dovecot pop3/imap STARTTLS email server with an ordinary email client, e.g., Evolution or Thunderbird. We can connect to the host server in a host of different ways (no pun intended)—http, https, ssh, vnc, telnet, openssl -sclient Similarly we can connect to postfix and dovecot in yet another number of ways—telnet, openssl -sclient—but cannot log in to the email server with a normal email client (either Evolution or Thunderbird) by either pop3 or imap. SSL certificates are in place, verified, and tested. Part of the problem is the many changes in all the involved operating systems and protocols (e.g., imaps and pop3s are deprecated, openSUSE has migrated to LEAP, etc.) so many of the docs from Google are no longer valid. Additionally, there simply are bugs: Leap 42.1 YAST does not work when it comes to setting up websites. Documented. But I digress. I'm sure it's something really simple, but it evades me. Research details below. Any help would be more than appreciated. Thanks in advance, Andy ======================= Configuration testing details ======================= System is: Linux openSUSE Leap 42.1 Dovecot --version 2.2.18, Postfix Version: 2.11.6-3.1 Apache2 Version: 2.4.16-9.1 Connections 1. Evolution or Thunderbird to pop3 or imap reports: The reported error was "Could not connect to mail.privustech.com: Connection refused". Both connect successfully to googlemail.com with the same protocol: Port 993 SSL on a dedicated port I have also tried Port 143 STARTTLS after connecting without success 2. openssl s_client -connect mail.privustech.com:xxx a. xxx=25, 110, 143 all return error:140770FC b. xxx=993, 995 return socket: Connection refused connect:errno=111 3.telnet to a. smtp works. b. pop3 andy@tm2t:~> telnet 70.186.159.22 110 ... +OK POP3 2007e.104 server ready <48fa.572a0769(a)privustech.com> ... user andy -ERR Unknown AUTHORIZATION state command c. imap connects but does not allow login, and should not. http://marc.info/?l=imap&m=118775891829506&w=2 The most simple answer is "you cannot TELNET to a modern, correctly-configured, IMAP server and log in to it." andy@tm2t:~> telnet 70.186.159.22 143 ... * OK [...] privustech.com IMAP4rev1 2007e.404 at Wed, 4 May 2016 10:26:28 -0400 (EDT) ... A NO Invalid login credentials Modules • Apache2 works just fine. The server is up and answering. ping works just fine. We have http and https to all vhost sites (privustech, mailprivustech, nptbeyond, gvhl, truthcourage, and their www. subsites). • Postfix reports no errors. We can log in on localhost, send a message to ourselves and see the message. • Dovecot: a. Logging is enabled in 10-logging.conf to /var/log/dovecot.conf but no logging has occurred there. b. doveconf -n throws no errors. Checks and tests completed 1. /etc/hosts is just fine. 2. Firewall is open for telnet, postfix, dovecot. 3. Added andy to dovecot, postfix groups, in addition to mail, reset password to ANDYbbs14@. 4. We tried enabling imaps, pop3s, but this command returns errors about these protocols being obsolete. https://tools.ietf.org/html/rfc2595 Use of these ports is discouraged in favor of the STARTTLS or STLS commands. 5. Reviewed doveconf -n: a. Note, there are no Dovecot users established other than user postfix group postfix service auth { unix_listener auth-userdb { group = postfix user = postfix } } i. postfix has its own set of users, including andy, which works just fine within postfix. We can send mail and read mail in the mailbox. b. Authentication is performed by PAM: passdb { driver = pam } i. Examined PAM: A. The files /etc/pam.d/xxx, where xxx = dovecot, pop, imap, are all the same lavarre:~ # cat /etc/pam.d/xxx #%PAM-1.0 auth include common-auth account include common-account password include common-password session include common-session B. They do not resemble at all the form presented in http://wiki2.dovecot.org/PasswordDatabase/PAM passdb { driver = pam args = %s } C. Add (B.) to see if that works: No change. Comment out the original (A.): No change. Restore it. c. SSL is required and apparently configured correctly (the less-than symbol '<'causes the succeeding file to be read into the variable): ssl = required ssl_cert = </etc/ssl/certs/dovecot.pem ssl_dh_parameters_length = 2048 ssl_key = </etc/ssl/private/dovecot.pem ssl_options = no_compression ssl_prefer_server_ciphers = yes userdb { driver = passwd } i. dovecot.pem, both cert and key, are installed in /etc/ssl as above and verified as a pair with openssl x509. And we point to them in /etc/dovecot/conf.d/10-ssl.conf as seen in the above. 6. Checked listening as it does not appear in doveconf -n: lavarre:~ # doveconf protocols listen protocols = imap pop3 lmtp listen = *, :: a. conf.d/10-master.conf ports for service xxx-login {inet_listener} are commented out. In fact, the entire file is commented out. Uncomment the listeners, restart. But no change. So undo.

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