I just made a Deadwood snapshot update which is intended for people to more widely test Deadwood. I would like more people to test the compression code with Deadwood.
Testing release: The compression code does not affect packets coming to and from the resolver. However, every time Deadwood gets a DNS packet, it decompresses then recompresses the packet. If the recompressed packet differs from the packet received from the upstream DNS server, Deadwood logs a "WARNING: Compression problems with packet" error, followed by the DNS packet causing problems. This log message is then followed by the length of the compressed packet, the packet as actually compressed by Deadwood, and finally the string value and length of the question.
This allows me (and anyone who wishes to help) to test Deadwood's compression core with real-world DNS packets. In addition, I will make some acid tests for the compression core (tests like making sure we never compress SRV RRs but can understand packets with compressed SRV records, etc.) which I will use to further test Deadwood's compression core with.
Since it would be nice to see some wider testing in this snapshot, I have made both the source code and a 7zip compressed Windows binary of the snapshot available here.
I will release Deadwood 2.4.04 when I'm satisfied that testing has ironed out the bugs in the compression core.