May 2021 - dovecot - dovecot.org

mail_crypt module and error with tmp directory
by Fiorenza Meini 04 May '21

04 May '21

Hi, I successfully enable mail_crypt module but I'm experiencing a strange behaviour with tmp directory while accessing with POP3 protocol: I see in log file: Error: istream-seekable: safe_mkstemp(/tmp/dovecot.pop3.) failed: Permission denied I changed tmp directory configuration (mail_temp_dir variable) and setting it with 777 permission, but the error is the same. On client side it's working everything, but I'd like to understand the error and if I have to be worried about it. Thank you and regards Fiorenza -- Fiorenza Meini/Spazio Web Via Dante Alighieri, 10 - 13900 - BIELLA tel. +39 015 2431982-1 - fax 015 2522600 https://esseweb.eu -- Questo messaggio e i suoi allegati ai sensi del Regolamento (UE) 2016/679 sono indirizzati esclusivamente alle persone indicate. La diffusione, copia o qualsiasi altra azione derivante dalla conoscenza di queste informazioni sono rigorosamente vietate. Qualora abbiate ricevuto questo documento per errore siete pregati di darne immediata comunicazione al mittente e provvedere alla sua distruzione.

2 8

[Dovecot] Doveadm sometimes failed "to iterate through some users" after upgrade to 2.2
by Alessio Cecchi 04 May '21

04 May '21

Hi, I'm running every week in cron "doveadm expunge -A mailbox Spam before 30d" and monthly "doveadm quota recalc -A". After the upgrade to dovecot 2.2.12 (from 2.1.17), "doveadm -A" sometimes exit with this error: doveadm(user(a)domain.com): Error: User listing returned failure doveadm: Error: Failed to iterate through some users # echo $? 75 If I re-run the same command the user where doveadm stops changeing (always in alphabetical order): info@ mario@ pippo@ zazza@ and finally, after 3 or 4 run, ends with success. I have enable debug (via doveadm -D and auth/mail debub in 10-logging.con) but there are no errors or difference in the log when doveadm exit with the error (error code is 75). If I run # doveadm expunge -A mailbox Spam savedbefore 30d doveadm works fine Can somebody help me? Here is my configuration: # dovecot -n # 2.2.12: /etc/dovecot/dovecot.conf # OS: Linux 2.6.32-5-amd64 x86_64 Debian 6.0.9 auth_debug = yes auth_master_user_separator = * auth_verbose = yes deliver_log_format = msgid=%m, from=%f, subject="%s": %$ dict { expire = mysql:/etc/dovecot/dovecot-dict-sql.conf.ext sqlquota = mysql:/etc/dovecot/dovecot-dict-sql.conf.ext } disable_plaintext_auth = no dotlock_use_excl = no first_valid_gid = 89 first_valid_uid = 89 imap_client_workarounds = delay-newmail tb-extra-mailbox-sep tb-lsub-flags imap_idle_notify_interval = 29 mins imap_logout_format = in=%i out=%o session=<%{session}> last_valid_gid = 89 last_valid_uid = 89 lda_mailbox_autocreate = yes lda_mailbox_autosubscribe = yes listen = * mail_debug = yes mail_fsync = always mail_location = maildir:~/Maildir mail_nfs_index = yes mail_nfs_storage = yes mail_plugins = quota expire maildir_very_dirty_syncs = yes managesieve_notify_capability = mailto managesieve_sieve_capability = fileinto reject envelope encoded-character subaddress comparator-i;ascii-numeric relational regex imap4flags copy include variables body enotify environment mailbox date ihave vnd.dovecot.duplicate mmap_disable = yes namespace { list = children location = maildir:%%h/Maildir:INDEX=~/Maildir/shared/%%u prefix = shared/%%n/ separator = / subscriptions = no type = shared } namespace inbox { inbox = yes location = mailbox Drafts { auto = subscribe special_use = \Drafts } mailbox Sent { auto = subscribe special_use = \Sent } mailbox "Sent Messages" { special_use = \Sent } mailbox Spam { auto = subscribe special_use = \Junk } mailbox Trash { auto = subscribe special_use = \Trash } prefix = separator = / } passdb { args = username_format=%Ld /etc/dovecot/extra/alias-domains-denylogin.txt deny = yes driver = passwd-file } passdb { args = /etc/dovecot/extra/master-users driver = passwd-file master = yes pass = yes } passdb { args = /etc/dovecot/dovecot-sql.conf.ext driver = sql } plugin { expire = Trash expire2 = Spam expire_dict = proxy::expire quota = maildir:UserQuota quota2 = dict:Quota Usage::noenforcing:proxy::sqlquota quota_grace = 10M quota_rule2 = Trash:storage=+100M quota_warning = storage=95%% quota-warning 95 %u quota_warning2 = storage=80%% quota-warning 80 %u sieve = ~/.dovecot.sieve sieve_before = /etc/dovecot/sieve/before.sieve sieve_dir = ~/sieve sieve_extensions = +vnd.dovecot.duplicate -vacation } pop3_client_workarounds = outlook-no-nuls oe-ns-eoh pop3_logout_format = top=%t/%p, retr=%r/%b, del=%d/%m, size=%s, bytes=%i/%o, session=<%{session}> protocols = imap pop3 sieve service auth-worker { process_limit = 1000 } service auth { client_limit = 5500 unix_listener auth-userdb { group = vchkpw mode = 0660 user = vpopmail } } service dict { process_limit = 300 unix_listener dict { group = vchkpw mode = 0660 user = vpopmail } } service imap-login { process_min_avail = 4 service_count = 0 } service imap { process_limit = 4000 service_count = 100 } service managesieve-login { inet_listener sieve { port = 4190 } } service pop3-login { service_count = 0 } service pop3 { process_limit = 1023 service_count = 100 } service quota-warning { executable = script /etc/dovecot/scripts/quota-warning.sh unix_listener quota-warning { user = vpopmail } user = vpopmail } ssl_cert = </etc/dovecot/ssl/wildcard-myemail.net.pem ssl_key = </etc/dovecot/ssl/wildcard-myemail.net.key submission_host = localhost userdb { args = /etc/dovecot/dovecot-sql.conf.ext driver = sql } protocol lda { mail_location = maildir:~/Maildir:INDEX=MEMORY mail_plugins = quota expire sieve } protocol imap { mail_max_userip_connections = 15 mail_plugins = quota expire imap_quota } protocol sieve { mail_max_userip_connections = 2 } protocol pop3 { mail_max_userip_connections = 5 } -- Alessio Cecchi is: @ ILS -> http://www.linux.it/~alessice/ on LinkedIn -> http://www.linkedin.com/in/alessice Assistenza Sistemi GNU/Linux -> http://www.cecchi.biz Cloud Email Hosting -> http://www.qboxmail.com @ PLUG -> ex-Presidente, adesso senatore a vita, http://www.prato.linux.it

3 3

Latest git FATAL error
by Joan Moreau 03 May '21

03 May '21

Hello On latest git of dovecot, I get Apr 24 04:07:36 gjserver dovecot[857958]: imap-login: Panic: file client-common.c: line 293 (client_disconnect): assertion failed: (client->prev == NULL && client->next == NULL) and login process crash On 2.3.14, there is no problems Hope it helps JM

3 17

Problem with Log-File
by Volf, Ronald (IRV) 03 May '21

03 May '21

Hello ! We want to log error in a File directly : /var/log/IRV_MdM/Dovecot_main.log. We got this error: 'Can't open log file /var/log/IRV_MdM/Dovecot_main.log: Permission denied' Please have a look at our Problem. Is it a bug or an incorrect config ? Our Dir-Structure is: (for testing, we changed all to mod 777) 2021-05-03 04:29:32 IRV-20210501-V02-rvh:~ # dir -d /var/ /var/log/ /var/log/IRV_MdM/ /var/log/IRV_MdM/Dovecot_main.log drwxrwxrwx 11 root root 4096 2021-04-30 20:36:51 /var/ drwxrwxrwx 21 root root 4096 2021-05-03 02:53:34 /var/log/ drwxrwxrwx 4 IRV_MdM IRV_MdMG 4096 2021-05-03 04:28:09 /var/log/IRV_MdM/ -rwxrwxrwx 1 IRV_MdM IRV_MdMG 14 2021-05-03 01:36:18 /var/log/IRV_MdM/Dovecot_main.log 2021-05-03 04:29:48 IRV-20210501-V02-rvh:~ # Version: 2021-05-03 04:28:05 IRV-20210501-V02-rvh:~ # dovecot --version 2.3.14 (cee3cbc0d) 2021-05-03 04:28:12 IRV-20210501-V02-rvh:~ # Logs: 2021-05-03 04:28:51 IRV-20210501-V02-rvh:~ # doveadm log find Debug: /var/log/IRV_MdM/Dovecot_main.log Info: /var/log/IRV_MdM/Dovecot_main.log Warning: /var/log/IRV_MdM/Dovecot_main.log Error: /var/log/IRV_MdM/Dovecot_main.log Fatal: /var/log/IRV_MdM/Dovecot_main.log Config: 2021-05-03 04:45:27 IRV-20210501-V02-rvh:~ # dovecot -n # 2.3.14 (cee3cbc0d): /etc/dovecot/dovecot.conf # Pigeonhole version 0.5.14 (1b5c82b2) # OS: Linux 5.12.0-1-default x86_64 ext3 # Hostname: IRV-20210501-V02-rvh auth_cache_size = 20 M auth_debug = yes auth_debug_passwords = yes auth_verbose = yes auth_verbose_passwords = plain default_internal_user = IRV_MdM default_login_user = IRV_MdM_Login deliver_log_format = msgid=%m: %$ (From=%f, To=%t, Subject=%s, Size=%p/%w, Dsn=%{storage_id}) disable_plaintext_auth = no first_valid_uid = 10000 last_valid_gid = 49999 last_valid_uid = 49999 listen = * log_path = /var/log/IRV_MdM/Dovecot_main.log log_timestamp = "%Y-%m-%d %H:%M:%S " login_greeting = Welcome to the INetS - Multi-Device-Mail-Server. mail_access_groups = IRV_MdMG mail_debug = yes mail_location = maildir:/var/spool/IRV_MdM/User/%u/Mail:CONTROL=/var/spool/IRV_MdM/User/%u/C trl:INDEX=/var/spool/IRV_MdM/User/%u/Index:LAYOUT=fs mail_temp_dir = /var/spool/IRV_MdM/Tmp 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 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 = } passdb { args = /etc/dovecot/dovecot-sql.conf.ext driver = sql } plugin { sieve = file:~/sieve;active=~/.dovecot.sieve } pop3_client_workarounds = outlook-no-nuls oe-ns-eoh postmaster_address = <mailto:Support@IRV.at> Support(a)IRV.at ssl_cert = /Apps_IRV/Web/Cert/IRV_star_irv_at/IRV_STAR_irv_at.Crt.crt ssl_cipher_list = ALL:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@STRENGTH ssl_key = # hidden, use -P to show it ssl_options = no_compression ssl_prefer_server_ciphers = yes userdb { driver = prefetch } userdb { args = /etc/dovecot/dovecot-sql.conf.ext driver = sql } verbose_proctitle = yes 2021-05-03 04:45:42 IRV-20210501-V02-rvh:~ # OS: 2021-05-03 04:45:42 IRV-20210501-V02-rvh:~ # i_ver Isg-Release: Version = 07.00.22 from 2021-01-22 21:13. Linux-Release: openSUSE Tumbleweed 20210430 Linux 5.12.0-1-default x86_64. 2021-05-03 05:13:01 IRV-20210501-V02-rvh:~ # Please send the reply to Support(a)IRV.at. Mit freundlichen Grüßen / with best regards Ing. Ronald VOLF <http://www.irv.at/> IRV Datenverarbeitung GmbH Internet: <http://www.irv.at/> www.irv.at Mail: <mailto:Sales@IRV.at> Sales(a)IRV.at Tel.: (+43-2236) 2236 7 * Fax: (+43-2236) 2191 7 / 30 Addr.: Brown Boveri Strasse 6, Top 18 2351 Wr. Neudorf, Austria

3 2

Sieve - disable redirect
by Miloslav Hůla 03 May '21

03 May '21

Hi, I would like to disallow "redirect" in sieve scripts to prevent automatical e-mail forwarding out of organisation. I'dint find a way in [1], only "sieve_extensions" option and when I try "sieve_extensions = -redirect" I got: # sievec test.sieve sievec(root): Warning: sieve: ignored unknown extension 'redirect' while configuring available extensions Is there any way? Kind regards Milo [1] https://doc.dovecot.org/configuration_manual/sieve/configuration/

1 1

setmetadata and NIL
by Steffen 03 May '21

03 May '21

Hi everybody, I played with Dovecot's metadata in dovecot-core 2:2.3.14-5+debian9 from repo deb https://repo.dovecot.org/ce-2.3-latest/debian/stretch stretch main https://tools.ietf.org/html/rfc5464#section-4.3 and https://github.com/coi-dev/coi-specs/blob/master/webpush-spec.md use NIL to remove items. Unsubscribe To unsubscribe from push notification set the previously push annotation to NIL. *Example for unsubscribing from push notifications: * C: a SETMETADATA "" (/private/vendor/vendor.dovecot/webpush/subscriptions/31754ee7-d3ee-4226-b112-6895ed26fcf8 NIL) S: a OK SETMETADATA complete and C: a SETMETADATA INBOX (/private/comment NIL) S: a OK SETMETADATA complete In the above example, the entry "/private/comment" is removed from the mailbox "INBOX". However, the metadata is stored as string NIL instead of removed: cat /home/user/Maildir/dovecot-attributes priv/369c8f17e81ff151f40400002e27b77f/vendor/vendor.dovecot/pvt/server/vendor/vendor.dovecot/webpush/subscriptions/31754ee7-d3ee-4226-b112-6895ed26fcf8 NIL priv/369c8f17e81ff151f40400002e27b77f/comment NIL shared/369c8f17e81ff151f40400002e27b77f/comment NIL a GETMETADATA (DEPTH 1) "" (/private/vendor/vendor.dovecot/webpush/subscriptions) * METADATA "" (/private/vendor/vendor.dovecot/webpush/subscriptions/31754ee7-d3ee-4226-b112-6895ed26fcf8 {3} NIL) a OK Getmetadata completed (0.001 + 0.000 secs). Do I have misinterpreted the samples? I though, the metadata is to be removed and getmetadata should not return the string NIL. Kind regards, -- Steffen

2 1

Can the disable_plaintext_auth setting get overridden for a specific port?
by Steve Dondley 03 May '21

03 May '21

In 10-auth.conf, I have "disable_plaintext_auth = yes" For port 143, I'd like to do something like this to override that setting: service imap-login { inet_listener imap { port = 143 disable_plain_text_auth = no } } Based on https://wiki.dovecot.org/LoginProcess and https://doc.dovecot.org/configuration_manual/service_configuration/ it doesn't seem like this is supported. But maybe there is another way to accomplish this?

3 2

Error and Panic (with coredump)
by Thomas Knaute 03 May '21

03 May '21

Hi there, i'm pretty new to this stuff, just tell me if you need more information. Apr 26 17:15:43 dilia dovecot: imap(user(a)domain.de)<78561><rtYxnuHAZoPAqBSC>: Error: i_stream_seekable_write_failed: close((&sstream->fd)) @ istream-seekable.c:246 failed (fd=21): Bad fi le descriptor Apr 26 17:15:43 dilia dovecot: imap(user(a)domain.de)<78561><rtYxnuHAZoPAqBSC>: Panic: file istream-seekable.c: line 226 (read_from_buffer): assertion failed: (*ret_r >0) Apr 26 17:15:43 dilia dovecot: imap(user(a)domain.de)<78561><rtYxnuHAZoPAqBSC>: Error: Raw backtrace: /usr/lib/dovecot/libdovecot.so.0(+0xdb73b) [0x7f13aead973b] -> /usr/lib/dovecot/libdov ecot.so.0(+0xdb7d1) [0x7f13aead97d1] -> /usr/lib/dovecot/libdovecot.so.0(+0x4a199) [0x7f13aea48199] -> /usr/lib/dovecot/libdovecot.so.0(+0x4c7cf) [0x7f13aea4a7cf] -> /usr/lib/dovecot/libdove cot.so.0(+0xee6e2) [0x7f13aeaec6e2] -> /usr/lib/dovecot/libdovecot.so.0(+0xeeb46) [0x7f13aeaecb46] -> /usr/lib/dovecot/libdovecot.so.0(+0xe6cd9) [0x7f13aeae4cd9] -> /usr/lib/dovecot/libdovec ot.so.0(i_stream_get_size+0x2a) [0x7f13aeae5baa] -> /usr/lib/dovecot/modules/lib20_zlib_plugin.so(+0x417c) [0x7f13ae80817c] -> /usr/lib/dovecot/libdovecot-storage.so.0(index_mail_set_seq+0x2 5) [0x7f13aec57eb5] -> /usr/lib/dovecot/libdovecot-storage.so.0(+0xd19ce) [0x7f13aec5e9ce] -> /usr/lib/dovecot/libdovecot-storage.so.0(index_storage_search_next_nonblock+0x61) [0x7f13aec5f0e 1] -> /usr/lib/dovecot/libdovecot-storage.so.0(mailbox_search_next_nonblock+0x28) [0x7f13aebe7e58] -> dovecot/imap [user(a)domain.de 192.168.xxx.xxx UID SORT](+0x2695f) [0x55740be9495f] -> dovecot/imap [user(a)domain.de 192.168.xxx.xxx UID SORT](imap_search_start+0xdc) [0x55740be9528c] -> dovecot/imap [user(a)domain.de 192.168.xxx.xxx UID SORT](cmd_sort+0x271) [0x55740be87b7 1] -> dovecot/imap [user(a)domain.de 192.168.xxx.xxx UID SORT](command_exec+0x70) [0x55740be8ddc0] -> dovecot/imap [user(a)domain.de 192.168.xxx.xxx UID SORT](+0x1e3f2) [0x55740be8c3f2] -> dovecot/imap [user(a)domain.de 192.168.xxx.xxx UID SORT](+0x1e494) [0x55740be8c494] -> dovecot/imap [user(a)domain.de 192.168.xxx.xxx UID SORT](client_handle_input+0x1b5) [0x55740be8c845] -> dovecot/imap [user(a)domain.de 192.168.xxx.xxx UID SORT](client_input+0x7e) [0x55740be8cd6e] -> /usr/lib/dovecot/libdovecot.so.0(io_loop_call_io+0x6f) [0x7f13aeaefbef] -> /usr/lib/dovec ot/libdovecot.so.0(io_loop_handler_run_internal+0x136) [0x7f13aeaf11e6] -> /usr/lib/dovecot/libdovecot.so.0(io_loop_handler_run+0x4c) [0x7f13aeaefc8c] -> /usr/lib/dovecot/libdovecot.so.0(io_ loop_run+0x40) [0x7f13aeaefdf0] -> /usr/lib/dovecot/libdovecot.so.0(master_service_run+0x13) [0x7f13aea70123] -> dovecot/imap [user(a)domain.de 192.168.xxx.xxx UID SORT](main+0x325) [0x5574 0be7ebf5] -> /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xeb) [0x7f13ae85709b] Apr 26 17:15:44 dilia dovecot: imap(user(a)domain.de)<78561><rtYxnuHAZoPAqBSC>: Fatal: master: service(imap): child 78561 killed with signal 6 (core dumped) # 2.3.4.1 (f79e8e7e4): /etc/dovecot/dovecot.conf # Pigeonhole version 0.5.4 () # OS: Linux 4.19.0-9-amd64 x86_64 Debian 10.9 # Hostname: dilia.intern.domain.de auth_cache_size = 10 M auth_default_realm = domain.de auth_mechanisms = plain login default_vsz_limit = 1 G disable_plaintext_auth = no imapc_features = " fetch-headers" imapc_host = mail.intern.domain.de imapc_user = %u mail_location = maildir:~/Maildir mail_plugins = zlib acl mail_prefetch_count = 20 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 envir onment mailbox date index ihave duplicate mime foreverypart extracttext namespace { hidden = no ignore_on_failure = no inbox = no list = children location = maildir:%%h/Maildir:INDEX=%h/shared/%%u:CONTROL=%h/shared/%%u prefix = shared/%%u/ separator = / subscriptions = yes type = shared } namespace inbox { hidden = no inbox = yes list = yes location = mailbox Drafts { auto = subscribe special_use = \Drafts } mailbox Junk { auto = subscribe special_use = \Junk } mailbox Sent { auto = subscribe special_use = \Sent } mailbox "Sent Messages" { special_use = \Sent } mailbox Trash { auto = subscribe special_use = \Trash } prefix = INBOX/ separator = / subscriptions = yes type = private } passdb { args = /etc/dovecot/dovecot-ldap.conf.ext driver = ldap } plugin { acl = vfile acl_shared_dict = file:/var/lib/dovecot/db/shared-mailboxes.db mail_log_events = delete undelete expunge copy mailbox_delete mailbox_rename mail_log_fields = uid box msgid size sieve = file:~/sieve;active=~/.dovecot.sieve zlib_save = gz zlib_save_level = 6 } protocols = " imap lmtp sieve" service auth { unix_listener /var/spool/postfix/private/auth { mode = 0666 } unix_listener auth-userdb { group = vmail user = vmail } } service imap-login { process_min_avail = 12 service_count = 0 } service imap { process_limit = 8192 } service lmtp { inet_listener lmtp { address = 127.0.0.1 port = 24 } } service managesieve-login { inet_listener sieve { port = 4190 } inet_listener sieve_deprecated { port = 2000 } } ssl_cert = </etc/ssl/certs/mail.intern.combined.cer ssl_cipher_list = ALL:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW:!DH@STRENGTH ssl_dh = # hidden, use -P to show it ssl_key = # hidden, use -P to show it ssl_min_protocol = TLSv1.2 ssl_prefer_server_ciphers = yes userdb { driver = prefetch } userdb { args = /etc/dovecot/dovecot-ldap.conf.ext driver = ldap } verbose_proctitle = yes protocol lmtp { mail_plugins = zlib acl sieve } protocol imap { mail_max_userip_connections = 20 mail_plugins = zlib acl imap_zlib imap_acl } Regards, Thomas

2 5

Sieve Auth failing (ignore previous message please)
by Dan Egli 02 May '21

02 May '21

Hi folks. I'm VERY new to Dovecot and Sieve. But I'm having an issue that I need help with. For some reason my sieve daemon won't allow people to log on. I have dovecot set to read information from a MySQL table, and that works fine. I can login to dovecot's imap server just fine. But I have SOGo for the webmail and it won't login to the sieve daemon. Here's what I see in the log files when I, for example, try to save my preferences in SOGo: ==> info.log <== Apr 28 00:33:14 lmtp(5938): Info: Connect from 127.0.0.1 ==> /var/log/sogo/sogod.log <== Apr 28 00:33:14 sogod [24168]: <0x0x557cfa9083c0[SOGoSieveManager]> failure. Attempting with a renewed password (no authname supported) Apr 28 00:33:14 sogod [24168]: <0x0x557cfa9083c0[SOGoSieveManager]> Could not login 'dan(a)newideatest.site' on Sieve server: <0x0x557cfaa03a70[NGSieveClient]: socket=<NGActiveSocket[0x0x557cfa89d540]: mode=rw address=<0x0x557cfa89d5d0[NGInternetSocketAddress]: host=localhost port=45456> connectedTo=<0x0x557cfa837c00[NGInternetSocketAddress]: host=127.0.0.1 port=4190>>>: {RawResponse = "{}"; result = 0; } ==> info.log <== Apr 28 00:33:14 lmtp(5938): Info: Disconnect from 127.0.0.1: Remote closed connection unexpectedly (state=READY) ==> /var/log/sogo/sogod.log <== Apr 28 00:33:14 sogod [24168]: 2600:387:8:7::70 "POST /SOGo/so/dan(a)newideatest.site/Preferences/save HTTP/1.1" 503 46/3676 0.024 - - 0 - 17 I've read a lot of pages about getting sieve running, but they show things I don't get. For example, from https://rtcamp.com/tutorials/mail/server/sieve-filtering/ I see that telnet localhost 4190 should give this: Escape character is '^]'. *"IMPLEMENTATION" "Dovecot Pigeonhole" "SIEVE" "fileinto reject envelope encoded-character vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy include variables body enotify environment mailbox date ihave" *"NOTIFY" "mailto" "SASL" "PLAIN LOGIN" "STARTTLS" "VERSION" "1.0" OK "Dovecot ready." But I don't see any of that. Escape character is '^]'. 220 jupiter.newideatest.site Dovecot ready. I've gotten to the point where I'm pulling my hair out. I don't understand dovecot well enough to even begin to guess what's going on. So I could REALLY use some pointers. Thanks all! Oh, ignore the first message. For some reason my MUA will occasionally send a draft to the smtp server. I still haven't figured that one out yet. -- Dan Egli From my Test Server

3 3

Ability to reject invalid client certificate at TLS handshake time
by Gert van Dijk 02 May '21

02 May '21

Hi, After a bit of struggling I've been able to set up TLS client certificate authentication with Dovecot for both IMAP and Submission. Users are required to present a valid certificate, cool so far! What I noticed however on non-StartTLS listeners IMAPS (993) and SMTPS (465), is that during the TLS handhake presenting a valid client certificate is seemingly optional and is only checked later at time of protocol-level login (external auth in my case). I'd like to change that for security purposes and also a bit of obscurity. Not having the ability to interact with Dovecot on protocol level lowers the attack vector as well as the ease of checking my network security. Also, it would prevent (anonymous) network scanners to easily detect what kind of service is running on the port as they can see the IMAP/SMTP banner without presenting a valid TLS client certificate currently. Is it possible in any version of Dovecot to configure it to set up a TLS server listening context that requires a handshake with a valid client certificate? I'm using Dovecot 2.3.4.1 (actual Debian Buster version 2.3.4.1-5+deb10u6), but willing to upgrade to any newer version when this is offered. Going through some newer revisions changelog this seems not the case, so I didn't spend time on upgrading yet. Relevant config snippets for IMAP authenticating proxy that I use (something similar for Submission): # Opens 143 on StartTLS and 993 in wrapped TLS-only mode. # Only 993 is exposed to the internet. protocols = imap passdb { driver = static args = proxy=y host=10.1.2.3 port=1143 pass=masterpass nopassword=y } auth_username_format = %n ssl = required ssl_cert = </etc/dovecot-ssl/cert.crt ssl_key = </etc/dovecot-ssl/key.pem ssl_prefer_server_ciphers = yes ssl_min_protocol = TLSv1.2 ssl_cipher_list = [omitted for brevity] ssl_ca = </etc/dovecot-ssl/client-ca.crt ssl_verify_client_cert = yes # Required to set this to 'no' if no CRL is set up yet ssl_require_crl = no auth_ssl_require_client_cert = yes # Take the username from the client certificate (CN) auth_mechanisms = external auth_ssl_username_from_cert = yes ssl_cert_username_field = commonName Current behaviour from a client when deliberately not presenting a client certificate shows the IMAP banner: $ openssl s_client -connect myserver:993 CONNECTED(00000003) --- Certificate chain 0 [...] --- Server certificate -----BEGIN CERTIFICATE----- [...] --- Acceptable client certificate CA names C = NL, O = Gert van Dijk, [...] --- SSL handshake has read 1096 bytes and written 413 bytes Verification: OK --- New, TLSv1.3, Cipher is TLS_AES_256_GCM_SHA384 Server public key is 384 bit Secure Renegotiation IS NOT supported Compression: NONE Expansion: NONE No ALPN negotiated Early data was not sent Verify return code: 0 (ok) --- * OK [CAPABILITY IMAP4rev1 SASL-IR LOGIN-REFERRALS ID ENABLE IDLE LITERAL+ LOGINDISABLED AUTH=EXTERNAL] Dovecot (Debian) ready. Expected: TLS alert during handshake, e.g. on my Apache TLS client certificate required configured instance: $ openssl s_client -connect myserver:443 139676785239360:error:14094410:SSL routines:ssl3_read_bytes:sslv3 alert handshake failure:../ssl/record/rec_layer_s3.c:1543:SSL alert number 40 IOW, I was hoping for something like this to exist: ssl_verify_client_cert = required OR service imap-login { inet_listener imaps { port = 993 ssl = client-cert-required } } Thanks, Gert

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