This algorithm is used by the Key Test2 callable service to generate and verify the verification pattern.

Where:

• VP is the 128-bit verification pattern
• TruncN(x) is truncation of the string x to the left most N bits
• SHA256(x) is the SHA-256 hash of the string x
• KA is the one-byte CCA variable-length key token constant for the algorithm of key (HMAC X'03')
• KT is the two-byte CCA variable-length key token constant for the type of key (MAC X'0002')
• KL is the two-byte bit length of the clear key value
• K is the clear key value left justified and padded on the right with binary zeros to byte boundary || is string concatenation