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derive_master_key_from_prekey

dpapi_core::masterkey

Function derive_master_key_from_prekey 

Source 
pub fn derive_master_key_from_prekey(
    mk: &MasterKey,
    pre_key: &[u8],
) -> Result<[u8; 64], DpapiError>
Expand description

Derive the 64-byte master key from a master-key sub-blob and a pre-key.

pre_key is the per-user pre-key (impacket’s deriveKeysFromUser output for the password path, or LSA UserKey/MachineKey for the SYSTEM path). Mirrors impacket MasterKey.decrypt: derive cryptKey || iv, CBC-decrypt, take the trailing 64 bytes, and verify the embedded HMAC; an HMAC mismatch (wrong pre-key) is rejected with DpapiError::HmacMismatch rather than returning garbage.