4.1.7 Key Confirmation
All changes in this version
Title changed
Before · SP 800-73-4
Key Confirmation
After · SP 800-73-5
Key Confirmation
Control changed
Before · SP 800-73-4
Key confirmation shall be performed in Steps C9 and H12 of the protocol in accordance with Sections 5.9.1.1 and 6.2.2.3 of [SP800-56A ] by the generation of AuthCryptogram ICC . AuthCryptogram ICC shall be computed as CMAC( MacKey , MacLen , MacData p ), where MacKey is SK CFRM , MacLen is 128 bits, and MacData p is "KC_1_V" || ID sICC || ID sH || Q eH . "KC_1_V" is a 6-byte ASCII string ('4B 43 5F 31 5F 56'). For Q eH , the coordinates of the ephemeral public key are converted from field elements to byte strings as specified in [SP800-56A , Appendix C.2], Field-Element-to-Byte String Conversion, and concatenated (with x first) to form a single byte string. CMAC is cipher-based message authentication code from [SP800-38B] , where the block cipher is AES.
After · SP 800-73-5
Key confirmation shall be performed in Steps C9 and H12 of the protocol in accordance with Sections 5.9.1.1 and 6.2.2.3 of [SP800-56A ] by the generation of AuthCryptogram ICC . AuthCryptogram ICC shall be computed as CMAC( MacKey , MacLen , MacData p ), where MacKey is SK CFRM , MacLen is 128 bits, and MacData p is "KC_1_V" || ID sICC || ID sH || Q eH . "KC_1_V" is a 6-byte ASCII string ('4B 43 5F 31 5F 56'). For Q eH , the coordinates of the ephemeral public key are converted from field elements to byte strings as specified in [SP800-56A , Appendix C.2], Field-Element-to-Byte String Conversion, and concatenated (with x first) to form a single byte string. CMAC is cipher-based message authentication code from [SP800-38B] , where the block cipher is AES.