August 2007 - dovecot

[Dovecot] Dovecot, LDAP and something akin to Postfix' "table search order" from virtual deliver.
by Pawel Sawicki 01 Feb '08

01 Feb '08

Hi. /* The short version. */ Is there a way to mimic Postfix' "table search order" in Dovecot's LDAP configuration of pass_filter/user_filter? /* Here goes the detailed description :) */ Just to quote the http://www.postfix.org/virtual.8.html: --- TABLE SEARCH ORDER (...) The search order is as follows. The search stops upon the first successful lookup. (...) o The user(a)domain.tld address, without address exten- sion, is looked up next. o Finally, the recipient @domain is looked up. --- Basicaly this allows to have separate users assigned addresses like j.doe(a)example.com (first account), j.smith(a)example.com (second account) and at the same time to have a "catch all" anything(a)example.com mailbox (for the administrator e.g.). What do I need it for? To have dovecot-lda working. Why? I want Sieve :) The test data may look as follows: account #1: + mail: j.doe(a)example.com + mailAlternateAddress: j.c.doe(a)example.com account #2: + mail: j.smith(a)example.com + mailAlternateAddress: j.t.smith(a)example.com account #3 (administrator): + mail: bofh(a)example.com + mailAlternateAddress: @example.com (means - anything possible) The filter I used is (more or less - for both pass_filter and user_filter): (|(mail=%u)(mailAlternateAddress=%u)(mailAlternateAddress=@%d)) Just for testing purposes I've stripped off some irrelevant data (like checking if the account is active), since that made the filter about 140 characters long ;) The trouble is when there're both a "catch all" and a true account that are linked to different accounts. As an example, if I try to send mail to "j.doe(a)example.com" I receive: dovecot: auth(default): ldap(j.doe(a)example.com): Multiple replies found for user Which is of course true, since the filter returns "account #2" and "account #3". What I'd like to get? I'd like to set the filter to: (|(mail=%u)(mailAlternateAddress=%u)) Where "%u" is expanded to "j.doe(a)example.com" during the first run Then, if dovecot can't find any user that would match this literaly it should retry the search operation, but now with "@example.com" as the "%u". I've tried to fiddle with the filter itself, but I see any reasonable way of doing it. I don't even know if it is possible at all. Could anyone give me a hint? Or maybe it's already on someone's whish list? Some final info. * I've followed the examples on dovecot.org website: http://wiki.dovecot.org/LDA#head-dacb9b9a1f19c3ea86bb6f8caa3d64e3ddad9ef8 * Here's the dovecot's master.conf entry: dovecot unix - n n - - pipe flags=DRhu user=mail:mail argv=/usr/libexec/dovecot/deliver -d ${recipient} Best regards! Pawel Sawicki

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[Dovecot] Too many open files
by Andrew Hutchings 10 Jan '08

10 Jan '08

Hi Guys, Just got this on one of my test72 dovecot servers: - Jun 10 12:40:28 svr21 dovecot: auth(default): net_connect_unix(/var/run/dovecot/auth-worker.18818) failed: Too many open files Jun 10 12:40:28 svr21 dovecot: pop3-login: Disconnected: method=PLAIN, rip=xxx.xxx.xxx.xxx, lip=xxx.xxx.xxx.xxx Jun 10 12:40:28 svr21 dovecot: pop3-login: Disconnected: method=PLAIN, rip=xxx.xxx.xxx.xxx, lip=xxx.xxx.xxx.xxx Jun 10 12:40:28 svr21 dovecot: child 18818 (auth) returned error 89 Jun 10 12:40:29 svr21 dovecot: Auth process died too early - shutting down Jun 10 12:40:29 svr21 dovecot: auth(default): mysql: Connected to localhost (maildb) Jun 10 12:40:29 svr21 dovecot: auth(default): net_connect_unix(/var/run/dovecot/auth-worker.13784) failed: No such file or directory Jun 10 12:40:29 svr21 dovecot: child 13784 (auth) returned error 89 - Is dovecot leaving files open? Or is it a large mailbox? Regards Andrew -- Andrew Hutchings (A-Wing) Linux Guru - Netserve Consultants Ltd. - http://www.domaincity.co.uk/ Admin - North Wales Linux User Group - http://www.nwlug.org.uk/ BOFH excuse 122: because Bill Gates is a Jehovah's witness and so nothing can work on St. Swithin's day.

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[Dovecot] What would you tell the CIO in an "ABCs of Email" overview?
by Esther Schindler 07 Jan '08

07 Jan '08

One of the key points that came up when I researched and wrote the "Five Things CIOs Should Know about Fighting Spam" article (http:// www.cio.com/article/28830) was that they should know the basics of how email works. Otherwise, said plenty of techies, the CIO won't have the first idea of what the email admin is complaining about. So I'm going to do my part. I'm going to write an "ABCs of Email" article (to accompany the many other ABCs articles we have on CIO.com, at http://www.cio.com/article/40242 ). I'd like your input on the topics that should be included, keeping in mind the fact that the target reader is a CIO, IT manager, or someone who wants to understand the basics, *not* actively get involved in email management. You don't need to write an essay for me or inundate me with links (though hey, if you want to make my life easier I shall not complain). What I'm looking for, primarily, are the categories of information that I should cover. In other words, if your CIO had an email ephiphany and asked you to give a half-hour presentation, what would you include? This won't be an "Expert says..." article nor will it be "Geek on the street says...." I intend to compile and research the "least you need to know" for the not-necessarily-techie bosses out there. And hopefully the end result will be that you have one less dumb question to deal with in your life. So: any suggestions? (You can reply privately if you prefer.) Esther Schindler senior online editor, CIO.com her blog: http://advice.cio.com/taxonomy/term/34

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[Dovecot] MANAGESIEVE patch v7 for dovecot 1.0.3 and TLS
by Andreas Schneider 09 Dec '07

09 Dec '07

Hi, I allow only TLS/SSL connection to dovecot. The managesieve doesn't work with TLS but it works without it. gladiac@magrathea:~> gnutls-cli -p 2000 -s --insecure -V milliways.cynapses.org Resolving 'milliways.cynapses.org'... Connecting to '213.239.217.124:2000'... - Simple Client Mode: - Received[194]: "IMPLEMENTATION" "dovecot" "SASL" "PLAIN" "SIEVE" "fileinto reject envelope vacation imapflags notify subaddress relational comparator-i;ascii-numeric regex" "STARTTLS" OK "Dovecot ready." STARTTLS - Sent: 9 bytes - Received[33]: OK "Begin TLS negotiation now." Let me know if you need more information. Thanks, -- andreas -- http://www.cynapses.org/ - cybernetic synapses

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[Dovecot] New full text search indexer
by Timo Sirainen 14 Nov '07

14 Nov '07

As described earlier (http://dovecot.org/list/dovecot/2006-December/018055.html) Dovecot nowadays has full text search indexing support in CVS HEAD. Currently there are two backends: Lucene and Squat. Lucene's problem is that standard IMAP SEARCH command can't be used with it without breaking IMAP RFC. So Lucene can be used only with non-standard X-BODY-FAST and X-TEXT-FAST search commands. Squat's code then is quite complex and it's pretty slow. It works with 4 character blocks, so it can answer: - Search string < 4 characters: Can't answer anything - Search string = 4 characters: Definite yes/no - Search string > 4 characters: Probable yes / definite no Since search strings are usually more than 4 characters, Dovecot uses the index only to filter out messages which definitely won't match and then does regular searching for the non-filtered messages. It works ok, but it could work better. The Squat indexes take maybe 30-50% of the mailbox's size. Most of the space goes to UID lists (list of messages matching each 4 character block). For example one UID list could be "2,4-10,20-30". This is already stored in a compressed format by storing the UID numbers relative to previous UID, which allows storing them usually with a single byte per UID, even if the UIDs are large. So, this morning I had an idea how this could maybe be improved with two changes: 1. Don't use 4 character blocks. Instead allow variable sized paths, and keep track of the UIDs for each node in the path. So for example adding "abc" to UID 1 will place the UID 1 to node "a", "ab" and "abc". 2. Use UIDs relative to parent's UIDs. For example if node "a" has UIDs 1,3,5 and "ab" is added for UID 5, the UID is changed to 2 (3th in 1,3,5 list - 1). This can help the compression a lot. The best case scenario for the above example is if "ab" contains also 1,3,5 UIDs. Then it can be written with a single 0-2 range. With these changes, the indexer can be configured to perform in different ways. Text can be indexed in two ways: full words, and substrings within those words (as required by IMAP). I think a useful combination of these would be to index all 4 character substrings and all full words up to 10 characters or so. This kind of an index can answer: - Search string <= 4 characters: Definite yes/no - For X-BODY-FAST / X-TEXT-FAST: - Search string 5-10 characters: Definite yes/no - Search string 11+ characters: Probable yes / definite no - For standard IMAP SEARCH: - Search string 5-10 characters: Definite yes if message contains the key as non-substring, otherwise same as below. This helps only if user does a search that matches a lot of messages. - Search string 11+ characters: Probable yes / definite no UTF-8 text is indexed as bytes, but the path depth can be counted as characters instead of as bytes. I've a test program finished, and unless there are some bugs left I think it shows that this can work pretty well: Squat-like 4 byte substrings (but can answer 1-3 char queries also): Message count: 7495 Index time: 4.19 CPU seconds (7.39MB/CPUs) Node memory: 3014072 bytes (2943 kB) in 90550 nodes UID memory: 8277212 bytes (8083 kB) in 352778 lists Total: 11291284 / 32474899 bytes = 34.77% Indexing the same mailbox file with squat-test gives: - Index time: 9.55 CPU seconds, 9.63 real seconds (3.24MB/CPUs) - 4145192 bytes in 102208 nodes (12.76%) - 7286058 bytes in 305501 uid_lists (22.44%) - 11431250 bytes total of 32474899 (35.20%) So the new indexer is over twice as fast and uses slightly less space. Indexing 4 char substrings and words up to 10 chars: Index time: 5.13 CPU seconds (6.04MB/CPUs) Node memory: 6002804 bytes (5862 kB) in 615501 nodes UID memory: 9044610 bytes (8832 kB) in 519488 lists Total: 15047414 / 32474899 bytes = 46.34% So it takes somewhat more space, but definitely less than having both Squat + Lucene. No substring indexing, words up to 10 chars (Lucene replacement): Index time: 1.39 CPU seconds (22.28MB/CPUs) Node memory: 3297663 bytes (3220 kB) in 548540 nodes UID memory: 1803735 bytes (1761 kB) in 213554 lists Total: 5101398 / 32474899 bytes = 15.71% Is there a need for Lucene anymore with this kind of a speed and disk space usage? :) The above tests are run with everything being indexed except space and control chars (ie. practically space + tab). If only alphanumeric characters are indexed, the total lines are (in same order as above): Total: 7048664 / 32474899 bytes = 21.70% (-13.07%) Total: 9610543 / 32474899 bytes = 29.59% (-16.75%) Total: 3963335 / 32474899 bytes = 12.20% (-3.51%) There are probably still a few optimizations that can be done to get the disk space usage even lower. I did spent quite a lot of time making it use less CPU though. Even tried a bit different coding style variations in the critical functions to get gcc to create faster code.. One interesting thing I noticed was that binary searching a character from a char array was slower than just sequentially going through the characters. I tried adding checks to do it only if the array was big, but it was always slower. Maybe something to do with CPU cache. If you want to try yourself, the test program is in http://dovecot.org/tmp/new-indexer.c

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[Dovecot] dovecot-1.0.3 & apacheds ldap
by sergey ivanov 31 Oct '07

31 Oct '07

I have problem with dovecot-1.0.3 and apacheds ldap server. If I change just uris in dovecot-ldap.conf to point to fedora-ds server, everything works O.K. I've tried with apacheds ldap server versions 1.0.2 and 1.5.0 command line search with parameters taken from dovecot.debug log gives me all needed attributes. Comments and help welcome. Here is my data: --- # /opt/dovecot/sbin/dovecot -n # 1.0.3: /opt/dovecot/etc/dovecot.conf log_path: /tmp/dovecot.log info_log_path: /tmp/dovecot.debug protocols: pop3 pop3s imap imaps ssl_cert_file: /etc/ssl/parkheights.cert ssl_key_file: /etc/ssl/parkheights.key login_dir: /opt/dovecot/var/run/dovecot/login login_executable(default): /opt/dovecot/libexec/dovecot/imap-login login_executable(imap): /opt/dovecot/libexec/dovecot/imap-login login_executable(pop3): /opt/dovecot/libexec/dovecot/pop3-login mail_extra_groups: mail mail_location: maildir:/var/spool/imap/%n/.imap mail_debug: yes mail_executable(default): /opt/dovecot/libexec/dovecot/imap mail_executable(imap): /opt/dovecot/libexec/dovecot/imap mail_executable(pop3): /opt/dovecot/libexec/dovecot/pop3 mail_plugin_dir(default): /opt/dovecot/lib/dovecot/imap mail_plugin_dir(imap): /opt/dovecot/lib/dovecot/imap mail_plugin_dir(pop3): /opt/dovecot/lib/dovecot/pop3 pop3_uidl_format(default): pop3_uidl_format(imap): pop3_uidl_format(pop3): %08Xu%08Xv auth default: verbose: yes debug: yes debug_passwords: yes passdb: driver: ldap args: /opt/dovecot/etc/dovecot-ldap.conf userdb: driver: ldap args: /opt/dovecot/etc/dovecot-ldap.conf userdb: driver: prefetch socket: type: listen master: path: /opt/dovecot/var/run/dovecot/auth-master mode: 384 user: vmail group: vmail --- # grep -v '#' /opt/dovecot/etc/dovecot-ldap.conf |grep -v '^\s*$' hosts = 192.168.10.43:389 dn = uid=admin,ou=system dnpass = Ahma3zoc sasl_bind = no auth_bind = no ldap_version = 3 base = ou=people,dc=parkheights,dc=dyndns,dc=org user_attrs = homeDirectory=home,uidNumber=uid,gidNumber=gid user_filter = (&(objectClass=posixAccount)(uid=%Ln)) pass_attrs = uid=user,gidNumber=userdb_gid,userPassword=password,homeDirectory=userdb_home,uidNumber=userdb_uid default_pass_scheme = MD5 --- # tail -5 /tmp/dovecot.debug dovecot: Aug 03 08:07:10 Info: auth(default): client in: AUTH 1 PLAIN service=IMAP secured lip=127.0.0.1 rip=127.0.0.1 resp=AHNlc(here_also_skipped_something)3N1Pg== dovecot: Aug 03 08:07:10 Info: auth(default): ldap(seriv,127.0.0.1): pass search: base=ou=people,dc=parkheights,dc=dyndns,dc=org scope=subtree filter=(&(objectClass=posixAccount)(uid=seriv)) fields=uid,gidNumber,userPassword,homeDirectory,uidNumber dovecot: Aug 03 08:07:10 Info: auth(default): ldap(seriv,127.0.0.1): result: uid(user)=seriv gidnumber(?unknown?)= userpassword(?unknown?)= homedirectory(?unknown?)= uidnumber(?unknown?)= dovecot: Aug 03 08:07:12 Info: auth(default): client out: FAIL 1 user=seriv temp dovecot: Aug 03 08:10:10 Info: imap-login: Disconnected: Inactivity: user=<seriv>, method=PLAIN, rip=127.0.0.1, lip=127.0.0.1, secured --- # tail -3 /tmp/dovecot.log dovecot: Aug 03 08:06:53 Warning: auth(default): Killed with signal 15 dovecot: Aug 03 08:06:53 Warning: Killed with signal 15 dovecot: Aug 03 08:07:10 Error: auth(default): ldap(seriv,127.0.0.1): No password in reply --- here is the snippet from apacheds debug log: --- message Id : 2 Search Request Base Object : 'ou=people,dc=parkheights,dc=dyndns,dc=org' Scope : whole subtree Deref Aliases : never Deref Aliases Size Limit : no limit Time Limit : no limit Types Only : false Filter : '(&(objectClass=posixAccount)(uid=seriv))' Attributes : gidNumber, uid, userPassword, homeDirectory, uidNumber baseDn : 'ou=people,dc=parkheights,dc=dyndns,dc=org' filter : '(& (objectClass=posixAccount) (uid=seriv) ) ' scope : whole subtree typesOnly : false no limit Time Limit : no limit Deref Aliases : never Deref Aliases attributes : 'gidNumber', 'uid', 'userPassword', 'homeDirectory', 'uidNumber' message Id : 2 Search Result Entry Object Name : 'uid=seriv,ou=people,dc=parkheights,dc=dyndns,dc=org' Attributes Attributes Attribute id : 'uid', Values : ['seriv'] Attribute id : 'gidnumber', Values : ['1927'] Attribute id : 'userpassword', Values : [0x7B 0x4D ... (skipped some bytes here) ... 0x3D 0x3D ] Attribute id : 'homedirectory', Values : ['/var/spool/imap/seriv'] Attribute id : 'uidnumber', Values : ['1001']

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[Dovecot] Possible Caching Bug showing up as a MIME Boundary Issue
by Kevin A. McGrail 27 Oct '07

27 Oct '07

Possible Caching Bug showing up as a MIME Boundary Issue I'm using Dovecot version 1.0.0. I was using Dovecot version 1.0.0 beta3 or alpha4. I upgraded to Dovecot 1.0.0 to make sure that was not the issue. Over the past few weeks on a server running a stable dovecot, I have seem a few emails arriving where the MIME document structure dividers are visible. I've included a screenshot showing this. Using OE6 as client. Have tried adding oe6-fetch-no-newmail per clients wiki but this seems to stop the ability to login at all. I am using two different machines with Outlook Express to access the same email. The same problem will show up on both. Usually, if I delete the .imap cache for the folder, the email comes down correctly. My dovecot -n output is: # /etc/dovecot.conf listen: *:144 ssl_listen: *:994 ssl_cert_file: /usr/local/ssl/certs/stunnel.pem ssl_key_file: /usr/local/ssl/certs/stunnel.pem disable_plaintext_auth: no login_dir: /var/run/dovecot/login login_executable: /usr/local/libexec/dovecot/imap-login max_mail_processes: 50 verbose_proctitle: yes default_mail_env: mbox:~/:INBOX=/var/spool/mail/%u mail_location: mbox:~/:INBOX=/var/spool/mail/%u imap_client_workarounds: outlook-idle delay-newmail auth default: passdb: driver: pam userdb: driver: passwd userdb: driver: prefetch The server is on a heavily modified RedHat 7.2 on x86 box with ext3 Thanks in Advance, KAM

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[Dovecot] dspam plugin
by Goran Mekić 30 Sep '07

30 Sep '07

When I drag n drop spam mail to SPAM folder, I get this error: Jun 11 17:58:46 sparrow dspam[28452]: Unable to open file for reading: /var/spool/dspam/data/local/mymail/mymail.sig/466d652f315451306914567.sig: No such file or directory mymail is user that runs dovecot transport (postfix config). The .sig file exist in /var/spool/dspam/data/<domain>/<user>/<user>.sig/466d652f315451306914567.sig. I've tried to google this problem, but no luck. Any advices? Thanx!

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[Dovecot] dovecot-dspam plugin & virtual users
by Wicher Minnaard 30 Sep '07

30 Sep '07

Hi list, hi Johannes, I'm trying to use the dovecot-dspam plugin ( http://johannes.sipsolutions.net/Projects/dovecot-dspam-integration ) with vpopmail's virtual users. All seems well, except for the fact that dspam should be called with '--user currentuser(a)currentdomain.com' at line 157 here: http://johannes.sipsolutions.net/Projects/dovecot-dspam-integration/beta7-c… For my needs, 'currentuser@currentdomain' could be taken as the login name I use for logging in to Dovecot. As I'm not a C-programmer by a long shot, I was wondering if one of you could help me use the bincimap-API to import the login name into a variable so I can use that variable to construct a suitable dspam-command. Hope this is possible! Regards, Wicher Minnaard

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[Dovecot] dovecot dspam plugin using libdspam
by Andreas Schneider 30 Sep '07

30 Sep '07

Hi, I've found the dovecot dspam plugin and looked at the code. I forks and calls the dspam binary for every mail. I didn't like this behavior, so I've migrated it to use libdspam. The plugin still needs more love: * Use cmake instead of a Makefile * Make the spam folder configurable in the dovecot.conf * Code cleanup and more comments. Please test. Comments and patches are welcome ;) http://www.cynapses.org/tmp/dovecot-dspam-plugin-0.1.tar.gz Cheers, -- andreas -- http://www.cynapses.org/ - cybernetic synapses

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