I use clamscan as a virus scanner.
It can analyse compressed files (rar, zip, etc...)
I want to use clamscan to analyse compressed files, and not amavis to decompress files before scanning.
(I set $bypass_decode_parts=1 in amavisd.conf)
But you have to ask clamav on the command line:
/usr/bin/clamscan -r --unzip --unrar
(else it doesnt scan compressed files)
This works on my configuration from the command line.
Unfortunately, in /etc/amavisd.conf, these option seem to be ignored: every infected compressed file passes through amavis and clamscan.
(on the opposite, a "normal" infected file, not compressed, it detected)
In amavisd.conf, I have:
$clamscan = "/usr/bin/clamscan -r --unzip --unrar"