daudit is a perl script that compares a computer's installed debian packages with any of the three debian releases. daudit downloads the packagelist from packages.debian.org and compares it with dpkg on the local machine. daudit does not write to disk, and you don't need root access to use it. As far as I know, this is the only debian package audit program like this. If you know of any others, let me know!
daudit depends on two debian perl library packages:
# apt-get install libcompress-zlib-perl # apt-get install libwww-perl
Usage: daudit [release] [arch]
Why did I write this software?
In order to downgrade a couple of my debian computers from mixed testing/stable to stable (for the security updates), I needed to know exactly which packages installed on my computer were from the testing release and which were from the stable release.
Note: Downgrading debian is non-supported, risky operation. I don't recommend doing it unless you are expreienced with debian. If you have physical access to a machine needing a downgrade, I would recommend just doing a new installation from scratch and copying your data over afterwards.