December 2014 - dovecot

SPECIAL-USE again
by Peter Mogensen 30 Dec '14

30 Dec '14

Hi, Great to see Thunderbird support SPECIAL-USE now. I would like to hear the list about the intended use of SPECIAL-USE. I get the impression from several earlier mails here that the intention is for the server to globally decide what the folder-name of a specific SPECIAL-USE folder is for all users. That's the way the documentation exemplifies it and what I get from posts like this: http://www.dovecot.org/list/dovecot/2013-February/088129.html I get the point that if *all* clients ignored the real folder-name and only obeyed SPECIAL-USE, the clients could locally in the GUI decide language and name of the \Sent, \Drafts, \Trash folders. And the real folder name would become just an opaque identifier. However that's not how the world is like. There are plenty of clients ignoring SPECIAL-USE and placing meaning in the actual folder name in a language of their own choice. It seems natural for me to let the user configure their own individual SPECIAL-USE tagging according to their language and/or mix of IMAP clients. - either by setting IMAP METADATA (RFC5464) or by having the userdb return entries like: "namespace/inbox/Papperskorg/specialuse=\Trash" (for a swede) /Peter PS: Also... Isn't there a need for a Sieve extension to allow "fileinto" to target a folder based on special-use ?

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Re: doveadm pw generates different hash each time it is invoked
by Joseph Tam 29 Dec '14

29 Dec '14

reik red writes: > (I'm re-submittting after setting up a subscription, so I don't have to wait for the moderator) > , > What happened next surprised me greatly: if I specify "-s ssha", the > resulting hashed password changes each time I invoke "doveadm pw", but > if I do not specify the hashing method, I get the same password each time (as I > expect). What on earth is going on here? There must be something > fundamental that I am missing. "doveadm pw" is working correctly. CRAM-MD5 and SSHA use hashing in 2 different ways to authenticate a user. CRAM-MD5 is a challenge-response system where the server sends the client a random string each and every session. The client hashes the password and the random string and sends it to the server as proof of authenticity. The server performs the same calculation to verify. However, the server needs to know the password (or password equivalent) in order to duplicate the hash calculation. SSHA precomputes the random strings (salt) and hashes the password with it, and stores both salt and hash in the password database. During authentication, the password is (or ought to be) transmitted plain within a SSL connection from the client to the server, then the server hashes the password with the stored salt and compares with the hash in the database. Every time you run "doveadm pw -s sha" a new random salt is generated, hence a new hash is produced even though you use the same password. You would use challenge-response in situations where the communication channel is insecure (i.e. non-SSL). However, the drawback is the password database contains enough information for someone to authenticate if it should fall into the wrong hands. Joseph Tam <jtam.home(a)gmail.com>

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Re: Awfully slow dovecot
by Joseph Tam 29 Dec '14

29 Dec '14

Robin Helgelin writes: > We?re using dovecot 1.0.7, which seems to be the latest version > available on CentOS 5. It wouldn't be a bad idea to update this if you can, even if you have to compile it yourself. You'll benefit from many bug fixes, one of which may solve your problem. > Downloading emails are dead slow. Really small emails goes quickly, > but normal emails and emails with attachments are so slow to download > it?s almost ridiculous. I?ve googled some and found that it could be > related to quota, but I disabled the quota plugins on imap with no > difference. The problem with "slowness" is that it can result from just about anything. I've seen reports of slowness caused by LDAP handups, filesystem and I/O polling, client issues, network issues, firewall issues, anti-virus stuff, resource starvation. That's just the stuff I remember. You'll need to dig further to reduce the scope of where it can be going wrong. I would suggest getting hints from - process tracing - network snooping - logs Test if it's a mail client issue by sampling more than one mail client (or better yet, talk IMAP directly to the server via telnet or netcat and download a large piece of Email). If that provokes a problem, work your way back to the server and do the same thing on the server itself (bypassing the network stack) and see if the problem still persists. Depending on what you find out, at least you'll know which side of the fence you should be looking at. (Also, asks yourself the obvious question: did you change anything before dovecot performance went down the tubes? New hardware? Patches?) Joseph Tam <jtam.home(a)gmail.com>

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Deleting files in sdbox
by Jeff Mitchell 28 Dec '14

28 Dec '14

Hello, I'm curious as to what happens if I were to manually delete files in an sdbox on the server. A long time ago -- I'm not sure how, as it was several years ago -- something happened and a number of users got a large number of mail messages duplicated. Literally duplicated -- all headers, all body content. I have a script that can find these duplicated messages (by ignoring the first few and last few lines of each message, and using SHAs to compare and find the duplicates). However, I don't see a doveadm style command to manually delete messages, except for doveadm-expunge. In the past I've used that with search queries but my experience is that trying to do many individual operations on individual files with doveadm-expunge can be quite slow. So, if Dovecot is going to just say "huh, my indexes/metadata are wrong, lemme rebuild them", I'd rather just rm the messages and let Dovecot do its thing. Again, this is with sdbox storage. Dovecot version is 2.2.9. Thanks! --Jeff

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Thunderbird supports SPECIAL-USE (Merry x-mas!)
by Patrick Ben Koetter 27 Dec '14

27 Dec '14

I've waited about two years to write this mail... :) As of Dezember, 24th Mozilla Thunderbird can handle SPECIAL-USE. The patch, which adds the required functionality, has passed review and TBs nightly build was successful. The next official Thunderbird release (version 38, release date 2015-05-19) will very likely ship SPECIAL-USE included. \o/ SPECIAL USE is an IMAP extension. It means less mailbox chaos for admins. But more than that it means less configuration work and easier orientation for end users. If IMAP server and client are capable of SPECIAL-USE [1] the server may tell the client some of the folders (Inbox, Drafts, Sent, Trash etc.) are reserved for SPECIAL-USE. Any client, capable of SPECIAL-USE, may adapts its local folders to the servers view. It may map e.g. "Sent Items" to "Sent", "Deleted Items" to "Trassh" etc. pp. All this takes place automatically. No more user interaction. No more locale problems. When all components - server, desktop-, webmail-, and mobile client - can handle SPECIAL-USE live becomes easier. Clients don't create their own 'special folders'. They understand special folders already exist and adapt. No more superfluous ambiguous folders. Users will know where their messages have been stored. Note: Combined with automx [2] users will only have to enter their realname, mail address and (optional) password and their client will setup all the rest automatically. SPECIAL-USE started as a suggestion to friends at IETF. We sponsored its implementation in Dovecot [3], when it had become a RFC standard. Then we took out to bring it to Thunderbird. This took use longer than expected. The moment we had begun to work on it, Mozilla withdrew most people from the Thunderbird team and reassigned them to Firefox OS. Things slowed down significantly and Microsoft Outlook became the first mail client to adopt SPECIAL-USE. Two years later - together with Ben Bucksch (Thunderbird developer) - we finally succeeded and it is about time to close the RFE [4]. Nobody should have to spend more time than required to configure their client. Everyone should be able to focus on their primary goal - communication via mail. We - sys4 and our business partner Becon - sponsored SPECIAL-USE. I hope SPECIAL-USE will make your and your customers life easier. The patch just became ready for x-mas. :) p@rick P.S. Unpacking the gift will have to wait until 2015-05-19. ;) [1] IMAP LIST Extension for Special-Use Mailboxes <http://tools.ietf.org/rfc/rfc6154.txt> [2] automx - mail setup made easy! <https://automx.org/> [3] Mailbox settings http://wiki2.dovecot.org/MailboxSettings [4] Bug 558659 - (RFC6154) Support IMAP LIST SPECIAL-USE (RFC 6154) to autoconfigure Sent, Trash, Draft folders on IMAP servers <https://bugzilla.mozilla.org/show_bug.cgi?id=558659> -- [*] sys4 AG https://sys4.de, +49 (89) 30 90 46 64 Franziskanerstraße 15, 81669 München Sitz der Gesellschaft: München, Amtsgericht München: HRB 199263 Vorstand: Patrick Ben Koetter, Marc Schiffbauer Aufsichtsratsvorsitzender: Florian Kirstein

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Awfully slow dovecot
by Robin Helgelin 26 Dec '14

26 Dec '14

Hi, We’re using dovecot 1.0.7, which seems to be the latest version available on CentOS 5. Downloading emails are dead slow. Really small emails goes quickly, but normal emails and emails with attachments are so slow to download it’s almost ridiculous. I’ve googled some and found that it could be related to quota, but I disabled the quota plugins on imap with no difference. dovecot -n: # 1.0.7: /etc/dovecot.conf ssl_cert_file: /etc/dovecot/cert.pem ssl_key_file: /etc/dovecot/key.pem disable_plaintext_auth: yes verbose_ssl: yes login_dir: /var/run/dovecot/login login_executable(default): /usr/libexec/dovecot/imap-login login_executable(imap): /usr/libexec/dovecot/imap-login login_executable(pop3): /usr/libexec/dovecot/pop3-login valid_chroot_dirs: /var/mail/domains verbose_proctitle: yes last_valid_uid: 500 mail_location: maildir:/var/mail/domains/%d/%n/mail mail_executable(default): /usr/libexec/dovecot/imap mail_executable(imap): /usr/libexec/dovecot/imap mail_executable(pop3): /usr/libexec/dovecot/pop3 mail_plugins(default): mail_plugins(imap): mail_plugins(pop3): quota mail_plugin_dir(default): /usr/lib/dovecot/imap mail_plugin_dir(imap): /usr/lib/dovecot/imap mail_plugin_dir(pop3): /usr/lib/dovecot/pop3 auth default: mechanisms: plain login passdb: driver: ldap args: /etc/dovecot/dovecot-ldap.conf userdb: driver: ldap args: /etc/dovecot/dovecot-ldap.conf socket: type: listen client: path: /var/spool/postfix/private/auth mode: 384 user: postfix group: postfix master: path: /var/run/dovecot/auth-master mode: 384 user: vmail group: mail plugin: convert_mail: maildir:/var/mail/domains/%d/%u/mail dovecot-ldap.conf: auth_bind = yes hosts = example.com ldap_version = 3 base = o=hosting,dc=example,dc=com dn = cn=phamm,o=hosting,dc=example,dc=com dnpass = password pass_attrs = mail pass_filter = (&(objectClass=VirtualMailAccount)(accountActive=TRUE)(mail=%u)) user_attrs = mail,,,mail,,,quota=quota=maildir:storage user_filter = (&(objectClass=VirtualMailAccount)(accountActive=TRUE)(mail=%u)) deref = never scope = subtree default_pass_scheme = MD5 user_global_uid = 500 user_global_gid = 12

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Curious dovecot behavior with service_count = 0
by anon_user＠openmailbox.org 26 Dec '14

26 Dec '14

Hello, I'm not experiencing this problem at all with service_count = 1 With service_count = 0, this is what I got randomly in my logs: TLS: SSL_read() syscall failed: Connection reset by peer To be successfully logged, the user have to initiate a new connection. I primary thought about vsz_limit but I've put this value to 10GB (yes this is very overkill, that was just for the test) and that don't change anything. I use the lastest version of dovecot. Any ideas ? Thanks.

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Re: Maildir permissions on creation?
by Von Random 26 Dec '14

26 Dec '14

The main reason is that I don't want to provide backup user with unnecessary write permissions within maildirs and mail user within backup logs dir. I was talking about mail_user:mail_group 0750 on dirs and 0640 on files. (Or, possibly, mail_user:backup_group 2750 and 2640.) 26.12.2014, 11:19, "Tobi" <tobster(a)brain-force.ch>: > Whats the reason you do not want to use default dovecot user. Your idea would assume that at least the group must have write access. For me a no-go on mailboxes. > > Am 24. Dezember 2014 13:21:15 MEZ, schrieb Von Random <von(a)vdrandom.org>: >> Hello. >> >> In my configuration dovecot reads home from mysql and uses no variables >> within it. It uses Maildir++ storage with virtual users. I also happen >> to use LMTP. >> >> I want to use a backup solution that does not involve running itself as >> root. Neither do I want to run it as dovecot's mail user. >> >> And there lies the problem: dovecot creates maildirs with 0700 and >> files within them inherit that set of permissions. And there seems to >> be no sane way to control it. I think I've figured out what to patch in >> order to change that default, but if possible, I'd like to avoid doing >> that. >> >> tl;dr: is it possible to change the default set of permissions for new >> maildirs created by dovecot? > > - -- > Diese Nachricht wurde von meinem Android-Mobiltelefon mit K-9 Mail gesendet. >> -----BEGIN PGP SIGNATURE----- >> Version: APG v1.1.1 >> >> iQI7BAEBCgAlBQJUnRoiHhxUb2JpIDx0b2JzdGVyQGJyYWluLWZvcmNlLmNoPgAK >> CRA1HOYlqGik5L9iD/9FIE2JzWfB7fWJEbI3vVg+ar4LRGwW1xNIf8ahlytPbsmH >> D9dFP3kWpJH6TO41AksNjz/FxHcUqSrlsKYTFUsDZCyb9Zyxd8Jv+dH04FwUzw+y >> kq+ayoylnTN7Q8mQnqkUpWEuYd5ohWbbUUSguwzN8Zd1T4jCFR9/Lvu0cweE6meu >> mBGwvXBbfBP4El+mAM2lKnoMXQpMycS6aX7FwQ/fBaoWSkzg/2az69UtqG6LLF67 >> ZhJkbn17cpT3y/l/2nV5urdcFVh8RoSXNuYyMN4r7IDKQ6BPsneD+839LS9X/gP/ >> QMuo5nO5xdx4q1bT9gtv1zz5eKAJ1f3R2oPZyxdpiV5PruSY3J3kvu0cF0aJvQF6 >> +s0iDsoDBcueB6JEUnYAarteWvBvxRnqb8ytju1xbIEkKLZtaS8Gf2cpZ8eA+Ha/ >> D0zkYfq7bt+Ra7BY6Qh7XMfiN5z9eWe5RqOmVLZRLf9N75U6wWa+fmXpvlqEtGNV >> pKsgif/ivCHiA24+JSJ1PBRjwO36Tu4MsSlT2WnkvyFBQzFzg9T00fl+uTXzgNEz >> SBta2wmXk9XVJ9mPzfNrAaAA3+T6H90Sj1CbRt7NZx30UdwYoIL5XXEtnG0p1XdS >> moe91H2UE+NT+jgj7emAOLxJf86vIwiHCqI0Zl/7wVNJEnKBXJP5WIHcdEDEHg== >> =Tl/z >> -----END PGP SIGNATURE-----

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doveadm pw generates different hash each time it is invoked !?
by reik red 26 Dec '14

26 Dec '14

I am absolutely dumbfounded by "doveadm pw". My understanding is that the command should be used to create a hashed password that should in turn be placed into /etc/dovecot/passwd Here comes the "dumbfounded" part. I was creating a new virtual user, running doveadm pw to generate the hashed password. But when I tried to login via imap, the password was rejected. So I started checking that I had populated /etc/dovecot/passwd with the correct values, and in the process I ran "doveadm pw" again to make certain I had not accidentally pasted the wrong value along with a username. (I'm re-submittting after setting up a subscription, so I don't have to wait for the moderator) , What happened next surprised me greatly: if I specify "-s ssha", the resulting hashed password changes each time I invoke "doveadm pw", but if I do not specify the hashing method, I get the same password each time (as I expect). What on earth is going on here? There must be something fundamental that I am missing. ============================================== Illustrative example: machine(user) 6136 > doveadm pw -u joebob Enter new password: Retype new password: {CRAM-MD5}00747cf2ffaf11c5ea4a64979c3901fc1d20dee13f480bb598f7d8575b23e61b machine(user) 6137 > doveadm pw -u joebob Enter new password: Retype new password: {CRAM-MD5}00747cf2ffaf11c5ea4a64979c3901fc1d20dee13f480bb598f7d8575b23e61b #SAME, as expected machine(user) > doveadm pw -u glorg Enter new password: Retype new password: {CRAM-MD5}00747cf2ffaf11c5ea4a64979c3901fc1d20dee13f480bb598f7d8575b23e61b #another surprising behavior: The (virtual) username specified does not affect the hash!!! machine(user) 6138 > doveadm pw -u joebob -s ssha Enter new password: Retype new password: {SSHA}AtjINkQra967qIhU6khRED4U1x3aKwDi machine(user) 6139 > doveadm pw -u joebob -s ssha Enter new password: Retype new password: {SSHA}fZiFlHPKDn6ESM/gnUIcjJ14hRlH10DV # DIFFERENT, very unexpected ============================================== I'm on fedora 19, using dovecot.x86_64 version 1:2.2.15-1.fc19 per yum.

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Dovecot-ee
by Davide 25 Dec '14

25 Dec '14

Hi to all, i found that dovecot-ee repository access is free 0,00 $ cost; i'm running dovecot community 2.2.13 can i migrate my system to dovecot-ee? What are difference between Dovecot-ee and Dovecot-community? -- *Davide Marchi* *T*eorema *F*errara *Srl* Via Spronello, 7 - Ferrara - 44121 Tel. *0532783161* Fax. *0532783368* E-m@il: *davide.marchi(a)mail.cgilfe.it* Skype: *davide.marchi73* Web: *http://www.cgilfe.it* *CONFIDENZIALITA'* *Ai sensi del D.Lgs. 196/2003 si precisa che le informazioni contenute in questo messaggio sono riservate ed a uso esclusivo del destinatario/dei destinatari. Qualora il messaggio in parola Le fosse pervenuto per errore, La invitiamo ad eliminarlo senza copiarlo e a non inoltrarlo a terzi, dandocene gentilmente comunicazione.* *Per favore, pensa all'ambiente. Stampa questa email solo se necessario.*

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