subjhash

This tool prints the SHA-256 hash of an X.509 certificate's subject
info or issuer fields. It can also verify that the hashes of the
subject are the same between two certificates.

Usage: subjhash [-im] certs...

Flags:
	-i	Print hash of issuer field.
	-m	Matching mode. This expects arguments to be in the form of
		pairs of certificates (e.g. previous, new) whose subjects
		will be compared. For example,

			subjhash -m ca1.pem ca1-renewed.pem	\
				ca2.pem ca2-renewed.pem

		will exit with a non-zero status if the subject in the
		ca1-renewed.pem certificate doesn't match the subject in the
		ca.pem certificate; similarly for ca2.