Ondřej Surý authored Mar 02, 2022 and Petr Špaček committed Sep 26, 2022

dns_message_checksig is called in a number of scenarios

	* on requests and responses
	* on multiple opcodes
	* with and without signatures
	* with TSIG signatures
	* with SIG(0) signatures
	* with and without configured TSIG keys
	* with and without KEY records being present
	* signing performed now, in the future and in the past

we use the first two octets of the seed to configure the calling
environment with the remainder of the seed being the rdata of the
TSIG/SIG(0) record.