CVD format

CVD (ClamAV Virus Database) is a digitally signed tarball containing one or more databases. The header is a 512-bytes long string with colon separated fields:

ClamAV-VDB:build time:version:number of signatures:functionality
level required:MD5 checksum:digital signature:builder name:build time (sec)

sigtool --info displays detailed information on CVD files:

zolw@localhost:/usr/local/share/clamav$ sigtool -i daily.cvd 
Build time: 11 Feb 2007 19-28 +0000
Version: 2553
# of signatures: 6063
Functionality level: 9
Builder: ccordes
MD5: 7f337b409249e11dea3effb04dd352f2
Digital signature: 6Ybd2eeDHBAs8raaEwmayqzoa5ysGDNnQ5Cc89mS2VCm1jRXZP
ke/itmkTyYQTc/rgJc2uQPr+NvzvUxRpsniwoyZ/gIkPniCLnqVCYOOytwtmirivbrV8j
0kzxb9nHd+5UQqj/Z3rLbS7T5HCbRX3uE0JX1tAo642Gq9ACH9Fc
Verification OK.