126.96.36.199 AES Cipher Usage
Advanced Encryption Standard (AES) encryption is achieved in this protocol by using the AEAD-AES-256-CBC-HMAC-SHA512 cipher<72>, as specified in [AES-CBC]. In order to use an encryption key, AES encryption requires a shared secret between the server and the client. Create this encryption key as a content encryption key (CEK), as specified in following methods, as appropriate:
For the SamrSetInformationUser2 method (section 188.8.131.52.4) with the UserInternal7Information (section 184.108.40.206.4.1) or UserInternal8Information (section 220.127.116.11.4.6) value, obtain the shared secret and CEK as the 16-byte user SMB session key, as specified in section 18.104.22.168.
The data MUST be encrypted and decrypted using AEAD-AES-256-CBC-HMAC-SHA512 as follows:
Let IV be a random 16-byte number.
Then the encryption is done as follows:
Let enc_key ::= HMAC-SHA-512(CEK, SAM_AES256_ENC_KEY_STRING)
Let mac_key ::= HMAC-SHA-512(CEK, SAM_AES256_MAC_KEY_STRING)
Let Cipher ::= AES-CBC(enc_key, IV, secret_plaintext)
Let AuthData ::= HMAC-SHA-512(mac_key, versionbyte + IV + Cipher + versionbyte_length)