determine HSM_KX header length from the prefix

Question

I have a sample HSM_KW message. It has a prefix of 3 characters that determines the length of the message header. In this sample message it is 00w. So how can I convert this into a number to know the length of the header?

Sample message:

\00w2551800114193044KW13U2B9989708BC34A58AE7F2A619DEC5C0008%E\00\01IPH\00

Answer 1

I would suspect \00 is a 0x00 byte and that's part of message length. Header length is configurable from console and not sent in the message. I would advise to consult with Host Programmer guide and you security personnel responsible for HSM configuration.