[courier-announce] Courier 0.52

[Sam V. <mr...@co...>]

Download: http://www.courier-mta.org/download.php

# This release is also available via BitTorrent.  This is mostly an
# academical excersize, SourceForge's resources are as healthy as ever.  The
# .torrent is created only to test my BitTorrent publication script (see 
# http://eztorrent.courier-mta.com).

This version of Courier includes an updated version of the maildrop mail 
filtering engine, and some security-related fixes to the webmail server (all=
 
previously released in development builds; there's nothing new here, move 
along).

Version 2.0 of maildrop introduces a new pattern matching engine that uses 
the PCRE library, that uses a completely different syntax. However, very few=
 
changes should be required to upgrade existing maildrop recipes to the new 
syntax.

Review the maildropfilter manual page which has been revised to document the=
 
new pattern matching syntax. The legacy pattern matching engine is still 
available by setting MAILDROP_OLD_REGEXP to 1. See also the "Conversion of 
maildrop 1.x patterns to 2.0" section in the maildropfilter manual page, for=
 
more information.

A corresponding change to the webmail server, sqwebmail, now uses PCRE to 
validate mail filtering patterns.  sqwebmail uses maildrop for mail 
filtering.  It is possible that some arkane existing pattern is no longer 
valid under maildrop 2.0. What will happen is that the first time 
SqWebMail's mail filtering screen is opened, the non-compatible filtering 
rules will be quietly deleted. This is a necessary even, and must be done, 
and the updated filtering rules must be saved, in order to enable mail 
delivery to this account.

Changes:

=E2=80=A2 mailbot: Do not autoreply to messages with an Auto-Submitted: head=
er, 
unless it's contents are "no"; and add Auto-Submitted: header on 
autoreplies.

=E2=80=A2 sqwebmail: Filter out MSIE-specific executable HTML comment format=
.

=E2=80=A2 sqwebmail: Remove attributes with imbalanced quotes, to prevent cr=
oss-side 
scripting  vulnerabilities with some browsers.

=E2=80=A2 sqwebmail: Show each attachment's MIME content type, explicitly.

=E2=80=A2 tcpd: Fix OpenSSL-less compilation

=E2=80=A2 rootcerts: updated list of trusted root certs

=E2=80=A2 imap: Fix NOT operator on content searches

=E2=80=A2 imap: Fix handling of invalid message sequence number 0

=E2=80=A2 waitlib: Probe for sigprocmask(), and use it if available, in favo=
r of 
sighold/sigrelse