RELEASE NOTES SPAMCONTROL 2.5
=============================

FEATURES
--------

SPAMCONTROL is an extension to qmail.

Enhancements for qmail-smtpd:

* ESMTP enhancements
- Strict RFC 2821 conformance.
- Reference 'Mail From:' parameter parser, supporting SIZE (RFC 1870) and AUTH options.
- Customizable SMTP Authentication (RFC 2554) support for LOGIN, PLAIN, and CRAM-MD5.
- SMTP Auth SUBMISSION feature.
- Optional STARTTLS (RFC 2487) support in conjunction with sslserver.

* SMTP envelope Anti-Spam-Tools
- Wildmat Filters for the HELO/EHLO greeting and the 
  'Mail From: <Return-Path>' in Split-Horizon fashion.
- DNS Lookup for the HELO/EHLO greeting (A/MX) and the domain part of the 'Mail From:' (MX).
- Customizable HELO/EHLO greeting checks including exceptions. #)
- Greetdelay, Tarpitting, and Smart Rejection in case of too many invalid Recipients. 

* Mail From: Address Verification
- Check, whether for Relayclients the domain part of <Return-Path> corresponds 
  to a local address (Reverse Split-Horizon).
- Full control of outgoing Mail From: SMTP envelope addresses
  in case of a SMTP authenticated user.

* Enhanced badmailfrom support
- Wildmat filter.
- 'badmailfromunknown' capabilities. 
- 'badmailfromwellknown' capabilities. 
- Anti-spoofing of own addresses. 

* Recipients extensions #)
- badrcptto wildmat filter.
- Restricting the number of allowed 'Rcpt To:' per SMTP session.
- Whitelisting: Controlling the reception of mails not only on a 
  rcpthosts base but rather on the complete <Forwarding-Path> with fast and 
  extensible cdb/PAM lookup, domain-wildlisting and VERP support.
- Customizable 550 or 450 return messages. 

* Virus prevention
- Reference badmimetypes implementation. #)
- Improved badloadertypes filter.
- Qmail High Performance Scanner Interface (QHPSI).
- Customizable SMTP 554 Reply Message.

* qmail-smtpd logging
- Extensible logging format.
- Logging for failed and accepted SMTP sessions.


Enhancements for qmail-remote:

* SMTP Authentication
- Supported are Auth types LOGIN and PLAIN.
- Additional authsenders control file.

* QMTP support +)
- Additional qmtproutes control file in addition to smtproutes.

* Fast delivery 
- Delivery to any DNS listed MX for that domain instead just the primary.
- Increased read buffer for delivery.

* Bounce host support +)
- Forward qmail-send bounces to dedicated QMTP hosts.
- Forward qmail-send bounces to dedicated SMTP hosts.


Enhancements for qmail-pop3d:

* STLS support


Limitations:

* As by today, some SSL envrionment variables are not 
  made available by sslserver.


Enhancements for qmail-queue:

* High speed virus scanner by means of QHPSI.
* Additional QMAILQUEUE usage.
* Optional BIGTODO support.
* Optional use of RC=33 for spam messages detected via qmail-queue replacement.


Enhancements for qmail-send:

* Bounce control
- Restricting the size of bounces.
- Doublebouncetrim.

* Additional recognition of local IP addresses
- Moreipme
- Notipme


External enhancements:

* Seemless support for djbdns lib instead dnslib.
* qmail-mrtg interface.
* Newanalyse for logs.
* rblsmtpd patch can be downloaded in addition.


With SPAMCONTROL qmail-smtpd can stand the two most common threats:

* Lexical and/or dictionary Spam attacks in particular to none-existing <Forwarding-Path> 
  and the subsequent generation of bounce messages to none-existing <Return-Path>.
* Virus Bombing and resource exhaustion due to the Virus Scanners.

With SPAMCONTROL you can guarantee the integrity and authentication of at least

* the domain part of the provided 'Mail From:" SMTP envelop address for RELAYCLIENTS
* even chained over serveral Qmail instances.

With SPAMCONTROL qmail-remote allows

* to dedicate email traffic to particular accounts/domains via QMTP handled by specific qmail instances
* to decouple queuing of bounces from regular emails to a dedicated qmail instance or bounce host.


CHANGES (2.4 -> 2.5)
--------------------

Userland:
#) Modified syntax in 'badhelo'.
[+) Additional GREETDELAY capabilitiy via patched rblsmptd => now part of rblsmtpd]
+) Added Qmail QMTP capabilities for qmail-remote.
-) Removed tarpitcount/tarpitdelay control file.
#) Additional detection of white spaces in Base64 attachements via BADMIMETYPE='!'.
+) Enhanced syntax of control/smtproutes, control/qmtproutes with the token '!@' for bounce control.
+) Added SUBMISSION port feature for qmail-smtpd.
#) Recipient 0.5 whith additional PAM support and domain recognition.

Internal:
+) Added Return Code '33' to qmail-queue and added display support for SpamAssassin et al in qmail-smtpd log message.
#) Improved WARLORD algorithm for less false positives and additional whitespace filtering.
*) Fixed one bug in qmail-remote PLAIN Auth + updated base64.c (gcc -O2 problem).
+) Added bouncecontrol to qmail-remote. 
*) Updates to Makefile (to respect conf-cc) and cdb*.c to cope with 64 bit architectures.


EXPERIMENTAL ADD-ONS
--------------------

Some features in SPAMCONTROL 2.5 sholl be considered as 'experimental' only.

QMQ:

The Qmail Multiple Queue feature can be used, but the skeletons to raise 
the individual instances' subdirectories and a corresponding setup-script 
is still incomplete/missing. 

DELIVERTO:

The qmail-queue.scan wrapper script can be used to conditionally 'deliver to'
detected spam emails to certain accounts. 
For normail use, the environment variable DELIVERTO shall be empty.



Erwin Hoffmann, Cologne 2009-04-05.