The mailing list for listmasters using Sympa

[Steve Shipway <address@concealed>]

So -- take an MD5 sum of the incoming message (minus headers and whitespace), 
and then reject if it matches an existing MD5 sum (for just that list?) in 
the last X minutes/days.

This seems an interesting idea, though I'd probably use a table in the 
database to hold the checksums, and have some periodic pruning job to kill 
off expired ones.

I think the best way to implement this would be via a custom send scenario 
with a custom test function.  The test function could take care of computing 
the MD5, and adding it to the database if necessary.  The benefit of using a 
custom scenario check function is that it doesnt require modification of the 
main Sympa code, just a new module in the Perl library.

I started to use a similar way to implement a posting-rate-limiting custom 
scenario test, though I never finished it.

Steve

Steve Shipway
University of Auckland ITS
UNIX Systems Design Lead
address@concealed
Ph: +64 9 373 7599 ext 86487