From ca2b94c5229bd474f612b57b67d796252a4aab7a Mon Sep 17 00:00:00 2001 From: sebres Date: Tue, 4 Oct 2022 14:03:07 +0200 Subject: [PATCH] fixes gh-3370: resolve extremely long search by repeated apply of non-greedy RE `(?:: (?:[^\(]+|\w+\([^\)]*\))+)?` with following branches (it may be extremely slow up to infinite search depending on message); added new regression tests amend to gh-3210: fixes regression and matches new format in aggressive mode too --- ChangeLog | 4 ++++ config/filter.d/dovecot.conf | 8 +++++--- fail2ban/tests/files/logs/dovecot | 22 ++++++++++++++++++++++ 3 files changed, 31 insertions(+), 3 deletions(-) Index: fail2ban-1.0.1/config/filter.d/dovecot.conf =================================================================== --- fail2ban-1.0.1.orig/config/filter.d/dovecot.conf +++ fail2ban-1.0.1/config/filter.d/dovecot.conf @@ -7,19 +7,21 @@ before = common.conf [Definition] +_daemon = (?:dovecot(?:-auth)?|auth) + _auth_worker = (?:dovecot: )?auth(?:-worker)? _auth_worker_info = (?:conn \w+:auth(?:-worker)? \([^\)]+\): auth(?:-worker)?<\d+>: )? -_daemon = (?:dovecot(?:-auth)?|auth) +_bypass_reject_reason = (?:: (?:\w+\([^\):]*\) \w+|[^\(]+))* prefregex = ^%(__prefix_line)s(?:%(_auth_worker)s(?:\([^\)]+\))?: )?(?:%(__pam_auth)s(?:\(dovecot:auth\))?: |(?:pop3|imap|managesieve|submission)-login: )?(?:Info: )?%(_auth_worker_info)s.+$ failregex = ^authentication failure; logname=\S* uid=\S* euid=\S* tty=dovecot ruser=\S* rhost=(?:\s+user=\S*)?\s*$ - ^(?:Aborted login|Disconnected|Remote closed connection|Client has quit the connection)(?:: (?:[^\(]+|\w+\([^\)]*\))+)? \((?:auth failed, \d+ attempts(?: in \d+ secs)?|tried to use (?:disabled|disallowed) \S+ auth|proxy dest auth failed)\):(?: user=<[^>]*>,)?(?: method=\S+,)? rip=(?:[^>]*(?:, session=<\S+>)?)\s*$ + ^(?:Aborted login|Disconnected|Remote closed connection|Client has quit the connection)%(_bypass_reject_reason)s \((?:auth failed, \d+ attempts(?: in \d+ secs)?|tried to use (?:disabled|disallowed) \S+ auth|proxy dest auth failed)\):(?: user=<[^>]*>,)?(?: method=\S+,)? rip=(?:[^>]*(?:, session=<\S+>)?)\s*$ ^pam\(\S+,(?:,\S*)?\): pam_authenticate\(\) failed: (?:User not known to the underlying authentication module: \d+ Time\(s\)|Authentication failure \([Pp]assword mismatch\?\)|Permission denied)\s*$ ^[a-z\-]{3,15}\(\S*,(?:,\S*)?\): (?:[Uu]nknown user|[Ii]nvalid credentials|[Pp]assword mismatch) > -mdre-aggressive = ^(?:Aborted login|Disconnected|Remote closed connection|Client has quit the connection)(?::(?: [^ \(]+)+)? \((?:no auth attempts|disconnected before auth was ready,|client didn't finish \S+ auth,)(?: (?:in|waited) \d+ secs)?\):(?: user=<[^>]*>,)?(?: method=\S+,)? rip=(?:[^>]*(?:, session=<\S+>)?)\s*$ +mdre-aggressive = ^(?:Aborted login|Disconnected|Remote closed connection|Client has quit the connection)%(_bypass_reject_reason)s \((?:no auth attempts|disconnected before auth was ready,|client didn't finish \S+ auth,)(?: (?:in|waited) \d+ secs)?\):(?: user=<[^>]*>,)?(?: method=\S+,)? rip=(?:[^>]*(?:, session=<\S+>)?)\s*$ mdre-normal = Index: fail2ban-1.0.1/fail2ban/tests/files/logs/dovecot =================================================================== --- fail2ban-1.0.1.orig/fail2ban/tests/files/logs/dovecot +++ fail2ban-1.0.1/fail2ban/tests/files/logs/dovecot @@ -115,6 +115,17 @@ Aug 28 06:38:51 s166-62-100-187 dovecot: # failJSON: { "time": "2004-08-28T06:38:52", "match": true , "host": "192.0.2.4", "desc": "open parenthesis in optional part between Disconnected and (auth failed ...), gh-3210" } Aug 28 06:38:52 s166-62-100-187 dovecot: imap-login: Disconnected: Connection closed: read(size=1003) failed: Connection reset by peer (auth failed, 1 attempts in 0 secs): user=, rip=192.0.2.4, lip=127.0.0.19, session= +# failJSON: { "time": "2004-08-29T01:49:33", "match": false , "desc": "avoid slow RE, gh-3370" } +Aug 29 01:49:33 server dovecot[459]: imap-login: Disconnected: Connection closed: read(size=1026) failed: Connection reset by peer (no auth attempts in 0 secs): user=<>, rip=192.0.2.5, lip=127.0.0.1, TLS handshaking: read(size=1026) failed: Connection reset by peer +# failJSON: { "time": "2004-08-29T01:49:33", "match": false , "desc": "avoid slow RE, gh-3370" } +Aug 29 01:49:33 server dovecot[459]: imap-login: Disconnected: Connection closed: SSL_accept() failed: error:1408F10B:SSL routines:ssl3_get_record:wrong version number (no auth attempts in 0 secs): user=<>, rip=192.0.2.5, lip=127.0.0.1, TLS handshaking: SSL_accept() failed: error:1408F10B:SSL routines:ssl3_get_record:wrong version number +# failJSON: { "time": "2004-08-29T01:49:33", "match": false , "desc": "avoid slow RE, gh-3370" } +Aug 29 01:49:33 server dovecot[459]: managesieve-login: Disconnected: Too many invalid commands. (no auth attempts in 0 secs): user=<>, rip=192.0.2.5, lip=127.0.0.1 +# failJSON: { "time": "2004-08-29T01:49:33", "match": false , "desc": "avoid slow RE, gh-3370" } +Aug 29 01:49:33 server dovecot[459]: managesieve-login: Disconnected: Connection closed: read(size=1007) failed: Connection reset by peer (no auth attempts in 1 secs): user=<>, rip=192.0.2.5, lip=127.0.0.1 +# failJSON: { "time": "2004-08-29T01:49:33", "match": false , "desc": "avoid slow RE, gh-3370" } +Aug 29 01:49:33 server dovecot[472]: imap-login: Disconnected: Connection closed: SSL_accept() failed: error:14209102:SSL routines:tls_early_post_process_client_hello:unsupported protocol (no auth attempts in 0 secs): user=<>, rip=192.0.2.5, lip=127.0.0.1, TLS handshaking: SSL_accept() failed: error:14209102:SSL routines:tls_early_post_process_client_hello:unsupported protocol + # failJSON: { "time": "2004-08-29T03:17:18", "match": true , "host": "192.0.2.133" } Aug 29 03:17:18 server dovecot: submission-login: Client has quit the connection (auth failed, 1 attempts in 2 secs): user=, method=LOGIN, rip=192.0.2.133, lip=0.0.0.0 # failJSON: { "time": "2004-08-29T03:53:52", "match": true , "host": "192.0.2.169" } @@ -128,6 +139,17 @@ Aug 29 15:33:53 server dovecot: managesi # filterOptions: [{"mode": "aggressive"}] +# failJSON: { "time": "2004-08-29T01:49:33", "match": true , "host": "192.0.2.5", "desc": "matches in aggressive mode, avoid slow RE, gh-3370" } +Aug 29 01:49:33 server dovecot[459]: imap-login: Disconnected: Connection closed: read(size=1026) failed: Connection reset by peer (no auth attempts in 0 secs): user=<>, rip=192.0.2.5, lip=127.0.0.1, TLS handshaking: read(size=1026) failed: Connection reset by peer +# failJSON: { "time": "2004-08-29T01:49:33", "match": true , "host": "192.0.2.5", "desc": "matches in aggressive mode, avoid slow RE, gh-3370" } +Aug 29 01:49:33 server dovecot[459]: imap-login: Disconnected: Connection closed: SSL_accept() failed: error:1408F10B:SSL routines:ssl3_get_record:wrong version number (no auth attempts in 0 secs): user=<>, rip=192.0.2.5, lip=127.0.0.1, TLS handshaking: SSL_accept() failed: error:1408F10B:SSL routines:ssl3_get_record:wrong version number +# failJSON: { "time": "2004-08-29T01:49:33", "match": true , "host": "192.0.2.5", "desc": "matches in aggressive mode, avoid slow RE, gh-3370" } +Aug 29 01:49:33 server dovecot[459]: managesieve-login: Disconnected: Too many invalid commands. (no auth attempts in 0 secs): user=<>, rip=192.0.2.5, lip=127.0.0.1 +# failJSON: { "time": "2004-08-29T01:49:33", "match": true , "host": "192.0.2.5", "desc": "matches in aggressive mode, avoid slow RE, gh-3370" } +Aug 29 01:49:33 server dovecot[459]: managesieve-login: Disconnected: Connection closed: read(size=1007) failed: Connection reset by peer (no auth attempts in 1 secs): user=<>, rip=192.0.2.5, lip=127.0.0.1 +# failJSON: { "time": "2004-08-29T01:49:33", "match": true , "host": "192.0.2.5", "desc": "matches in aggressive mode, avoid slow RE, gh-3370" } +Aug 29 01:49:33 server dovecot[472]: imap-login: Disconnected: Connection closed: SSL_accept() failed: error:14209102:SSL routines:tls_early_post_process_client_hello:unsupported protocol (no auth attempts in 0 secs): user=<>, rip=192.0.2.5, lip=127.0.0.1, TLS handshaking: SSL_accept() failed: error:14209102:SSL routines:tls_early_post_process_client_hello:unsupported protocol + # failJSON: { "time": "2004-08-29T16:06:58", "match": true , "host": "192.0.2.5" } Aug 29 16:06:58 s166-62-100-187 dovecot: imap-login: Disconnected (disconnected before auth was ready, waited 0 secs): user=<>, rip=192.0.2.5, lip=192.168.1.2, TLS handshaking: SSL_accept() syscall failed: Connection reset by peer # failJSON: { "time": "2004-08-31T16:15:10", "match": true , "host": "192.0.2.6" }