support for DNS blacklists

Vernon Schryver vjs@calcite.rhyolite.com
Tue Jul 19 19:59:35 UTC 2005


It seems that the support for DNS blacklists in dccm, dccifd, and dccproc
has gone unnoticted. 

All three DCC client programs can check DNS blacklists.

The mechanism checks URLs in the body or URLs in the body and envelope
names and IP addresses in DNS blacklists.  Better than some MTA DNS
blacklist support, it has time limits on each DNS lookup and on all
of them together, which I figure might be important to busy mail systems.

Also better than some MTA support, it can check for blacklisted  MX
servers.  That is currently handy if you want to reject mail from some
organizations that use many domain names and IP addresses but tend to
use a single MX server, presumably to for target list cleaning.

By default it marks without rejecting.  Some mailboxes should not use
it, such as abuse@example.com.  Rejecting for a user must be turned
on with "option DNSBL-on" in the global or a per-user whiteclnt file.

There is some documentation of -B in the dccm, dccifd, and dccproc
man pages.   
http://www.dcc-servers.net/dcc/dcc-tree/dccm.html#OPTION-B


Vernon Schryver    vjs@rhyolite.com



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