January 2025 - dovecot

Problem email client iPhone ios18.2
by andrzej.milewski＠gmail.com 17 Apr '25

17 Apr '25

Hello, I have a fairly new installation of the Dovecot server version 2.3.19.1 on Debian 12.8. In general, the server works correctly. It sends and receives emails without issues. The clients primarily use Thunderbird on desktops and Gmail on Android. However, some clients are using iPhones with various hardware versions. Those with iOS below version 18 work correctly without any issues. Those who have updated their phones to version 18 and now even 18.2 are experiencing problems with mailbox synchronization. On version 18.2, the issue appears as follows: When you open the app, you can read several messages. They load correctly, but, for instance, attachments do not. If I wait for some time, the attachment eventually loads. During this time, I observe the server logs, and it shows that a certain session on the Dovecot server has ended. Dec 17 13:13:01 iredmail0 dovecot[408]: imap(xxx(a)xxx.com)<44785><1QGZCHcp/+3AqM2O>: Disconnected: Connection closed (UID SEARCH finished 92.295 secs ago) in=2972 out=6076956 deleted=0 expunged=0 trashed=0 hdr_count=0 hdr_bytes=0 body_count=36 body_bytes=6059064 Dec 18 08:40:41 iredmail0 dovecot[408]: imap(xxx(a)xxx.com)<177412>: Disconnected: Connection closed (UID FETCH finished 90.079 secs ago) in=5126 out=1304237 deleted=0 expunged=0 trashed=0 hdr_count=94 hdr_bytes=289688 body_count=89 body_bytes=969615 Dec 18 08:42:19 iredmail0 dovecot[408]: imap(xxx(a)xxx.com)<177410><D5mqU4cpZ+nAqM2O>: Disconnected: Connection closed (UID FETCH finished 95.051 secs ago) in=4475 out=1162785 deleted=0 expunged=0 trashed=0 hdr_count=95 hdr_bytes=281674 body_count=61 body_bytes=839545 Dec 18 08:44:17 iredmail0 dovecot[408]: imap(edyta.kowalewska(a)laktopol.com.pl)<177918>: Disconnected: Connection closed (UID FETCH finished 92.132 secs ago) in=29399 out=30266644 deleted=0 expunged=0 trashed=0 hdr_count=565 hdr_bytes=1726228 body_count=628 body_bytes=28109455 After the session is closed, the attachment loads immediately. From the logs and router analysis, it appears that the download happens in another previously opened session. After this incident, I go to another message with an attachment, and the situation repeats. There are also situations where the email body does not load, and the app waits for the server until the session closes and the content is fetched in another session. It does not matter whether I connect to the server via the internet or through a local network. On an iPhone 7 with iOS 15.8.3, everything works smoothly. Attachments open without issues. On iOS 18.1.1, attachments do not load, and the session does not close on its own. It takes forever unless the app is closed. In the Gmail app, everything works correctly without any issues. This is clearly a problem with the mail client on iPhone. However, is there anything I can adjust in my server settings to mitigate this issue for users? My dovecot configuration https://pastebin.com/UPNQ5dZz

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Stats-writer permission denied
by Ken Wright 15 Apr '25

15 Apr '25

I've got a new Dovecot error (well, new to me, at least)! I ran tail /var/log/mail.err and got the following: net_connect_unix(/var/run/dovecot/stats-writer) failed: Permission denied I checked the file, and it's owned by www-data and the www-data group, with read and write permissions for owner and group... just like I have specified in /etc/dovecot/conf.d/10-master.conf. I can't understand why permission is denied when the file permissions appear to be correct. Can anyone shed any light on this for me? Ubuntu 20.04 Dovecot 2.3.7.2 Ken

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[Dovecot] auth: Error: net_connect_unix(anvil-auth-penalty) failed: Permission denied
by mailing＠securitylabs.it 02 Apr '25

02 Apr '25

Hello, just upgraded one of my testing machine from dovecot 1.2.15 to 2.0.7. After some trouble with permissions now all seems working, but when I stop dovecot I have these errors in log: Nov 9 17:08:07 in dovecot: master: Warning: Killed with signal 15 (by pid=20362 uid=0 code=kill) Nov 9 17:08:07 in dovecot: pop3-login: Error: read(anvil) failed: EOF Nov 9 17:08:07 in dovecot: imap-login: Error: read(anvil) failed: EOF Nov 9 17:08:07 in dovecot: imap(mailing(a)securitylabs.it): Server shutting down. bytes=410/59361 Nov 9 17:08:07 in dovecot: imap(mailing(a)securitylabs.it): Server shutting down. bytes=79/26605 Nov 9 17:08:07 in dovecot: imap(mailing(a)securitylabs.it): Server shutting down. bytes=802/55708 Nov 9 17:08:07 in dovecot: imap(mailing(a)securitylabs.it): Server shutting down. bytes=258/1242 Nov 9 17:08:07 in dovecot: auth: Error: read(anvil-auth-penalty) failed: EOF Nov 9 17:08:07 in dovecot: auth: Error: net_connect_unix(anvil-auth-penalty) failed: Permission denied dovecot -n: # 2.0.7: /usr/local/etc/dovecot/dovecot.conf # OS: Linux 2.6.32-5-xen-686 i686 Debian squeeze/sid auth_cache_negative_ttl = 2 mins auth_cache_size = 1000 M auth_cache_ttl = 2 mins auth_master_user_separator = * auth_username_chars = abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@& disable_plaintext_auth = no dotlock_use_excl = yes first_valid_uid = 100 last_valid_uid = 105 lock_method = dotlock log_timestamp = "%Y-%m-%d %H:%M:%S " login_greeting = Server ready. mail_fsync = never mail_gid = Debian-exim mail_location = maildir:~/Maildir:INDEX=/var/indexes/%d/%n mail_privileged_group = Debian-exim mail_uid = Debian-exim 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 namespace { inbox = yes location = prefix = separator = / type = private } namespace { location = maildir:~/Maildir/expunged prefix = EXPUNGED/ separator = / type = private } namespace { location = maildir:~/Maildir/deleted prefix = DELETED/ separator = / type = private } namespace { location = maildir:~/Maildir/deleted/expunged prefix = DELETED/EXPUNGED/ separator = / type = private } passdb { args = /usr/local/etc/dovecot-sql.conf driver = sql } passdb { args = /usr/local/etc/passwd.masterusers driver = passwd-file master = yes pass = yes } plugin { lazy_expunge = EXPUNGED/ DELETED/ DELETED/EXPUNGED/ mail_log_events = delete expunge mail_log_group_events = quota = maildir quota_warning = storage=80%% /usr/local/bin/dovecot-quota-warning.sh 80 quota_warning2 = storage=90%% /usr/local/bin/dovecot-quota-warning.sh 90 sieve = ~/.dovecot.sieve } pop3_no_flag_updates = yes protocols = imap pop3 service auth { unix_listener auth-userdb { group = Debian-exim mode = 0600 user = Debian-exim } } service imap-login { client_limit = 256 process_limit = 128 process_min_avail = 3 service_count = 1 } service imap { drop_priv_before_exec = yes process_limit = 256 vsz_limit = 256 B } service pop3-login { client_limit = 256 process_limit = 128 process_min_avail = 3 service_count = 1 } service pop3 { drop_priv_before_exec = yes process_limit = 256 vsz_limit = 256 B } ssl_cert = </usr/local/etc/dovecot.crt ssl_key = </usr/local/etc/dovecot.key userdb { args = /usr/local/etc/dovecot-sql.conf driver = sql } protocol imap { mail_max_userip_connections = 10 mail_plugins = " notify quota imap_quota mail_log lazy_expunge" } protocol pop3 { mail_max_userip_connections = 3 mail_plugins = " notify quota mail_log" pop3_uidl_format = %08Xu%08Xv } protocol lda { mail_plugins = quota sieve postmaster_address = postmaster(a)securitylabs.it } My /usr/local/var/run/dovecot directory: 4 drwxr-sr-x 4 root staff 4096 Nov 9 17:08 . 4 drwxrwsrwx 3 root staff 4096 Nov 9 17:05 .. 0 srw------- 1 root staff 0 Nov 9 17:05 anvil 0 srw------- 1 root staff 0 Nov 9 17:05 anvil-auth-penalty 0 srw------- 1 root staff 0 Nov 9 17:05 auth-client 0 srw------- 1 dovecot staff 0 Nov 9 17:05 auth-login 0 srw------- 1 root staff 0 Nov 9 17:05 auth-master 0 srw------- 1 Debian-exim Debian-exim 0 Nov 9 17:05 auth-userdb 0 srw------- 1 dovecot staff 0 Nov 9 17:05 auth-worker 0 srw------- 1 root staff 0 Nov 9 17:05 config 0 srw------- 1 root staff 0 Nov 9 17:05 dict 0 srw------- 1 root staff 0 Nov 9 17:05 director-admin 0 srw-rw-rw- 1 root staff 0 Nov 9 17:05 dns-client 0 srw------- 1 root staff 0 Nov 9 17:05 doveadm-server 0 lrwxrwxrwx 1 root staff 35 Nov 9 17:05 dovecot.conf -> /usr/local/etc/dovecot/dovecot.conf 4 drwxr-xr-x 2 root root 4096 Nov 9 17:05 empty 4 drwxr-x--- 2 root dovenull 4096 Nov 9 17:05 login My emails are delivered as user Debian-exim and users are virtual in a MySQL DB. This system is behind a proxy (so the master user)

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Bug: Logout counters reset after recreating hibernated process
by Eirik Rye 12 Mar '25

12 Mar '25

Hello, # dovecot --version 2.3.20 (80a5ac675d) When using hibernation (`imap_hibernate_timeout = 10s`), counters such as deleted/expunged messages, appear to be reset after the user process is recreated. Steps to reproduce: 1. Configure IMAP hibernation 2. Login with IMAP client 3. Delete+expunge a message 4. IDLE, and wait 10s for process to be hibernated 5. Unhibernate process (`DONE`), and log out 6. Observe the logged line: 2023-09-05T17:36:26+0200 imap(<redacted>)<776933><jA2nYJ4EPdcqAVtAAADwAAutur4AAAAB>: Info: Disconnected: Logged out in=9 out=88 deleted=0 expunged=0 trashed=0 hdr_count=0 hdr_bytes=0 body_count=0 body_bytes=0 The expected output is "deleted=1 expunged=1", not "deleted=0 expunged=0". If you follow the steps above, but skip the IDLE/hibernate step, the output is as expected. Interestingly, if the client is disconnected during hibernation (without recreating the process), the output from `imap-hibernate` is still as expected: 2023-09-05T17:45:15+0200 imap-hibernate(<redacted>)<770540><0qE0gJ4Emt8qAVtAAADwAAutur4AAAAB>: Info: Disconnected: Connection closed in=97 out=1020 deleted=1 expunged=1 trashed=0 hdr_count=0 hdr_bytes=0 body_count=0 body_bytes=0 This leads me to believe the counters are lost during process recreation, not during hibernation. This is an issue as customers will often come to us asking why messages have disappeared in their inbox, or asking for help to identify which client is expunging messages. Right now, this information is lost if hibernation is used and the client is hibernated after expunging. Best regards, Eirik Rye

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lua API and returning reason and CONTACTADMIN
by Arkadiusz Miśkiewicz 19 Feb '25

19 Feb '25

Hello. Trying to pass reason response via lua by passing it at dovecot.auth.PASSDB_RESULT_USER_DISABLED like: function auth_password_verify(request, password) return dovecot.auth.PASSDB_RESULT_USER_DISABLED, "reason=custom_message" end function auth_userdb_lookup(request) return dovecot.auth.PASSDB_RESULT_OK, "uid=428671 gid=9726 home=/var/mail/existusertest" end function script_init() return 0 end function script_deinit() end Unfortunately returned result contains no custom message and also returns AUTHENTICATIONFAILED instead of CONTACTADMIN: NO [AUTHENTICATIONFAILED] Authentication failed. while I would expect something like: NO [CONTACTADMIN] custom_message: Any reason for such behaviour and how to get reason passed and proper CONTACTADMIN? Tests done on 2.3.21.1. passdb { driver = lua mechanisms = login plain args = file=/etc/dovecot/lua_auth_script_test_fail.lua blocking=yes } userdb { driver = lua args = file=/etc/dovecot/lua_auth_script_test_fail.lua blocking=yes } -- Arkadiusz Miśkiewicz, arekm / ( maven.pl | pld-linux.org )

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Dovecot v2.4.0 released
by Aki Tuomi 16 Feb '25

16 Feb '25

Hi all, after a very long wait we are finally happy to release Dovecot v2.4.0! Some IMPORTANT things to notice: - We have changed the signing key for 2.4 going forward, releases are signed with EF0882079FD4ED32BF8B23B2A1B09EF84EDC5219, which can be found at https://repo.dovecot.org/DOVECOT-REPO-GPG-2.4 and is signed with the previous key. The old key has been renamed to https://repo.dovecot.org/DOVECOT-REPO-GPG-2.3. - New 2.4 packages **are not** compatible with old 2.3 configuration, please carefully review https://doc.dovecot.org/2.4.0/installation/upgrade/2.3-to-2.4.html before installing the new packages. - We are happy to provide experimental arm64 support in the form of a Docker image. - Docker images are now ran rootless, with UID 1000 as vmail using built sources. Please take this into consideration when upgrading. Latest 2.3 image can be used with tag 2.3-latest, if you are not ready for this change. We won't be sending separate mail about Pigeonhole anymore as we will release one anyways when we release Dovecot, and Pigeonhole versioning has been changed to match Dovecot versioning. Source codes available at - https://www.dovecot.org/releases/2.4/dovecot-2.4.0.tar.gz - https://www.dovecot.org/releases/2.4/dovecot-2.4.0.tar.gz.sig - https://pigeonhole.dovecot.org/releases/2.4/dovecot-pigeonhole-2.4.0.tar.gz - https://pigeonhole.dovecot.org/releases/2.4/dovecot-pigeonhole-2.4.0.tar.gz… Binary packages in https://repo.dovecot.org/ Docker images in https://hub.docker.com/r/dovecot/dovecot Kind regards, Aki Tuomi Open-Xchange oy --- Dovecot Core NEWS ----------------- * config: dovecot_config_version must be the first non-comment line in configuration file. * config: dovecot_storage_version must be in the configuration file. * config: Many configuration options have changed so old configuration files do not work without rewrite. See https://doc.dovecot.org/main/installation/upgrade/2.3-to-2.4.html * config: New variable expansion syntax has been introduced, see https://doc.dovecot.org/main/core/settings/variables.html * config: Some default settings have changed. * config: plugin {} section has been removed. * *-login: With ssl=required, connections from login_trusted_networks are now also required to be SSL/TLS encrypted. * acl: Use ACL settings instead of Global ACL Directories. * auth-worker: auth_worker_max_count is replaced with service auth-worker { process_limit }. * auth: Weak password schemes are disabled by default, use auth_allow_weak_schemes to enable them. * auth_debug, mail_debug: Use log_debug filter instead. * config: All sections require a name, for example passdb/userdb: passdb static { password=secret } * db2: Remove Berkeley DB support. * dict-memcached: This is removed, use Redis instead. * director: Feature has been removed. See potential replacement at https://github.com/dovecot/tools/blob/main/director.lua * doveadm: USER environment variable is only supported with --no-userdb-lookup. One of -u, -F or -A must be used otherwise. * doveconf: Option -n is now default when running doveconf. * dsync: Use doveadm sync instead, legacy symlink has been removed. * fs-sis: Feature is now deprecated and has been made read-only. It will be removed in future release. * fts-lucene, fts-squat: These have been removed, use fts-flatcurve or fts-solr instead. * imap-login: IMAP compression is now handled in proxies. * imap_quota: SETQUOTA / quota_set has been removed. * imap_zlib: This plugin is no longer needed, it's always enabled. * imapc: All features are enabled by default, imapc_features can be used to explicitly disable features that are not wanted. * lib-storage: mbox driver is now frozen. * mail_compress: XZ and LZMA algorithm support has been removed. * mailbox-alias: Plugin has been removed. * old_stats, auth_stats: These have been removed. * openssl: Minimum supported version of OpenSSL is now 1.1.1. * openssl: Add support for OpenSSL 3.x * quota-dict, quota-dirsize: These have been removed, use quota-count instead. You can use quota_clone to copy quota usage to some database. * replicator: Feature has been removed. Use NFS or some other shared filesystem instead, or run doveadm sync in crontab. * stats: The bytes_in and bytes_out field in several events have been renamed as net_in_bytes and net_out_bytes. * zlib: Renamed to mail_compress plugin. + Experimental SMTPUTF8 and IMAP UTF8=ACCEPT support has been added. Needs --enable-experimental-mail-utf8 configure option and mail_utf8_extensions=yes setting. + Long running mail commands can be aborted with Ctrl-C / doveadm kick. + auth: LDAP driver now supports multi-value attributes. + auth: Add support for SCRAM-SHA-1-PLUS and SCRAM-SHA-256-PLUS. + auth: Add support for TLS channel binding. + auth: Support sending JA3 hash to policy server. + configure: Detect latest Lua version. + *-login: Support for TLS Server Name has been improved to allow pre-login settings. For example capabilities to be changed based on TLS Server Name. + *-login: Support for TLS ALPN has been added, connections with mismatching application are now refused. Missing ALPN is accepted. + fts-flatcurve: New Xapian based FTS plugin has been added. + imap: Support for INPROGRESS untagged messages as per RFC 9585. + lib-lua: Expose Dovecot DNS client. + lib-lua: Expose Dovecot HTTP client. + lib-sasl: Support SCRAM-SHA mechanisms. + lmtp: SNI support has been added which allows settings to be applied based on TLS Server Name. + sqlite: Support WAL mode. + stats: Submetric name size has been increased. + submission: Add submission_add_received_header setting to protect sender identity by suppressing the Received: header. - Many bugs have been fixed. Pigeonhole NEWS --------------- * Change configuration syntax to match new Dovecot configuration syntax. * vacation: Reduce default days to 60 from infinity * vacation: vacation_max_period=0 is now an error. * Version has been changed to match Dovecot version. + Added i;unicode-casecmp comparator. - Lots of bugs have been fixed.

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Different Replicator Crash??
by Kent Borg 09 Feb '25

09 Feb '25

I added the suggested "count--" and recompiled, and it now appears to work, the replication goes both ways, eyeballing the e-mail on the two servers they look the same. Good. But part of the time I am still getting what looks very much like the same crash, is there another "count--" I need to add to that file? > Jan 28 10:53:08 la dovecot[96175]: replicator: Panic: data stack: Out > of memory when allocating 268435496 bytes > Jan 28 10:53:08 la dovecot[96175]: replicator: Error: Raw backtrace: > #0 t_askpass[0x7fb404b0c0] -> #1 backtrace_append[0x7fb404b374] -> #2 > backtr\ > ace_get[0x7fb404b510] -> #3 execvp_const[0x7fb4057ba4] -> #4 > i_syslog_fatal_handler[0x7fb4058510] -> #5 i_panic[0x7fb3fa6808] -> #6 > t_pop_pass_st\ > r[0x7fb4050eb4] -> #7 connection_deinit[0x7fb4056430] -> #8 > pool_datastack_create[0x7fb407e7b0] -> #9 > array_bsearch_insert_pos_i[0x7fb40446d0] ->\ > #10 t_base64_scheme_decode[0x7fb404cb24] -> #11 > buffer_append[0x7fb404d3d0] -> #12 replicator_queue_push[0x558c4b4f40] > -> #13 replicator_brain_i\ > nit[0x558c4b53e4] -> #14 _start[0x558c4b3d70] -> #15 > _start[0x558c4b3f04] -> #16 io_loop_call_io[0x7fb4072f20] -> #17 > io_loop_handler_run_interna\ > l[0x7fb4075450] -> #18 io_loop_handler_run[0x7fb4075680] -> #19 > io_loop_run[0x7fb4075944] -> #20 master_service_run[0x7fb3fd84b0] -> > #21 main[0x5\ > 58c4b3930] -> #22 __libc_init_first[0x7fb3dd76d0] -> #23 > __libc_start_main[0x7fb3dd7780] -> #24 _start[0x558c4b3b80] > Jan 28 10:53:08 la dovecot[96175]: replicator: Fatal: master: > service(replicator): child 96714 killed with signal 6 (core dumps > disabled - https:\ > //dovecot.org/bugreport.html#coredumps) Thanks, -kb

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Replicator Crash
by Kent Borg 05 Feb '25

05 Feb '25

I have replicator working well enough…to crash: > Jan 28 11:26:12 la dovecot[1187]: replicator: Panic: data stack: Out > of memory when allocating 268435496 bytes > Jan 28 11:26:12 la dovecot[1187]: replicator: Error: Raw backtrace: #0 > t_askpass[0x7fa59db0c0] -> #1 backtrace_append[0x7fa59db374] -> #2 > backtra\ > ce_get[0x7fa59db510] -> #3 execvp_const[0x7fa59e7ba4] -> #4 > i_syslog_fatal_handler[0x7fa59e8510] -> #5 i_panic[0x7fa5936808] -> #6 > t_pop_pass_str\ > [0x7fa59e0eb4] -> #7 connection_deinit[0x7fa59e6430] -> #8 > pool_datastack_create[0x7fa5a0e7b0] -> #9 > array_bsearch_insert_pos_i[0x7fa59d46d0] -> \ > #10 t_base64_scheme_decode[0x7fa59dcb24] -> #11 > buffer_append[0x7fa59dd3d0] -> #12 replicator_queue_push[0x556e8f4f40] > -> #13 replicator_brain_in\ > it[0x556e8f53e4] -> #14 _start[0x556e8f3d70] -> #15 > _start[0x556e8f3f04] -> #16 io_loop_call_io[0x7fa5a02f20] -> #17 > io_loop_handler_run_internal\ > [0x7fa5a05450] -> #18 io_loop_handler_run[0x7fa5a05680] -> #19 > io_loop_run[0x7fa5a05944] -> #20 master_service_run[0x7fa59684b0] -> > #21 main[0x55\ > 6e8f3930] -> #22 __libc_init_first[0x7fa57676d0] -> #23 > __libc_start_main[0x7fa5767780] -> #24 _start[0x556e8f3b80] > Jan 28 11:26:12 la dovecot[1187]: replicator: Fatal: master: > service(replicator): child 1185 killed with signal 6 (core dumps > disabled - https://\ > dovecot.org/bugreport.html#coredumps) This is on Debian 12. > # dovecot --version > 2.3.19.1 (9b53102964) There are gigabytes of free RAM, though it says it is trying to allocate 268,435,496 bytes--on the stack--and that does seem wrong in any case. The Maildir being synced is over 430MB, is that too much for dsync?? Suggestions? Thanks, -kb

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Clarification Question about migrating_mailboxes and broken doc link
by Aleks 02 Feb '25

02 Feb '25

Hi. I have read the https://doc.dovecot.org/2.3/admin_manual/migrating_mailboxes/#id7 and there is one part which is not 100% clear to me. We have 2 Dovecot servers mail1 (2.2.36.4) and mail2 ( 2.3.21 ). Now I have understood that I need to add this to mail1 ``` service doveadm { inet_listener { port = 12354 } } doveadm_password = supersecret ``` and this on mail2 ``` doveadm_password = supersecret ``` The question is for me now: I think that this command `doveadm backup -Ru username tcp:host:port` should be executed on the mail2. Is this assumption right? What I also found is that on that Page https://doc.dovecot.org/2.3/admin_manual/doveadm_mailbox_commands/ the wiki is linked for the manpages but the wiki link shows this. ``` The old wiki has been closed Our primary documentation is now at https://doc.dovecot.org, please update your links. ``` What's the right link for the manpages in the web? Best regards Aleks

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[Off-topic] ANN: Nauthilus
by Christian Rößner 01 Feb '25

01 Feb '25

Today I am pleased to announce the Nauthilus software. Nauthilus (N-Auth-ilus) is a centralized authentication server with a comprehensive policy engine. The idea behind this project is to connect services centrally in one place and perform extensive tests during authentication. # What can Nauthilus do and what problems does it solve? Many services on the Internet require authentication. Each application must then be connected to databases and must implement its own protective measures to ward off attackers. Every installation carries the risk of compromisation and therefore also access to the databases. With Nauthilus, the task is centralized in one place. Nauthilus is essentially an HTTP REST server that can be accessed by any application. It takes on the role of a guardian. Nauthilus integrates very well with Dovecot and Postfix. # Authentication process Nauthilus uses several authentication steps: ## 1. features Features include tests such as TLS verification, relay domains (is the system even responsible for the requested domain?), blocklists, RBLs and freely definable Lua features. Nauthilus has a powerful brute force concept with buckets to detect even slow attacks over days and weeks. It offers a bucket system for this purpose. ## 2. backend authentication Nauthilus includes LDAP support and Lua to perform the authentication itself. A large library of predefined functions is available in Lua, including SQL support. ## 3 Policies Policies are run through after authentication. Despite a successful login, the system can reject the login (or, conversely, allow it!). There is also space here for GeoIP lookups, etc. ## 4. Post-processing After the 3rd point, authentication has been completed, but at this point further tests can run in the background such as: * Check password policy and take action * Consult the Haveibeenpwnd network * GeoIP tracking across national borders and much more. ## Miscellaneous Nauthilus allows the free definition of so-called hooks. Each hook listens for a specific URI (callback) in the HTTP request. These callbacks are written by the administrator in Lua. In an initial proof of concept, Nauthilus can take on the role of a Dovecot director. This has already been tested with version 2.4.0. Currently, Nauthilus can dynamically delegate incoming connections to backends. The hooks concept is used here as an example. # Final words By integrating a Lua VM into the server, Nauthilus can be integrated and customized in almost any setup. See also the other Nauthilus-related projects listed in the appendix. To enable single sign-on (SSO), it can be operated with an Ory-Hydra server or the sister project nauthilus-keycloak can be used as a custom authenticator in Keycloak. 100% Open-Source 100% Community # Project https://github.com/croessner/nauthilus # Sub projects https://github.com/croessner/nauthilus-demo https://github.com/croessner/nauthilus-keycloak https://github.com/croessner/pfxhttp https://github.com/croessner/geoip-policyd # Mailing lists: https://lists.nauthilus.org N.B.: In the future, announcements are sent over the nauthilus-announce ML. This is just a hello world! Christian Rößner -- Rößner-Network-Solutions Zertifizierter ITSiBe / CISO Marburger Str. 70a, 36304 Alsfeld Fax: +49 6631 78823409, Mobil: +49 171 9905345 USt-IdNr.: DE225643613, https://roessner.website PGP fingerprint: 658D 1342 B762 F484 2DDF 1E88 38A5 4346 D727 94E5

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