* Fix TSIG bug releated to ID substitution
TSIG accounts for ID substitution. This means if the ID in the DNS
message is changed by for example a forwarder, TSIG calculation should
use the original message ID (from the TSIG RR).
I have a test for this as well, but it seems tsig_test.go has been
removed, so not sure where to put it now.
* Add tests for TSIG bugfix
These strings are domain names, so we should lowercase them before
using them.
Also add some tests for Tsig generation and verification.
(/ht ldns release).
Matthijs Mekking
Miek Gieben