private static Stream ReadStandardEncryptionInfo(TOle2File DataStream, TEncryptionData Encryption)
{
byte[] RecordHeaderLen = new byte[4];
DataStream.Read(RecordHeaderLen, RecordHeaderLen.Length);
long EncryptionHeaderSize = BitOps.GetCardinal(RecordHeaderLen, 0);
byte[] EncryptionHeader = new byte[EncryptionHeaderSize];
DataStream.Read(EncryptionHeader, EncryptionHeader.Length);
long AlgId = BitOps.GetCardinal(EncryptionHeader, 8);
long KeyBits = BitOps.GetCardinal(EncryptionHeader, 16);
TEncryptionParameters EncParams = TEncryptionParameters.CreateStandard(GetStandardEncAlg(AlgId));
byte[] VerifierBytes = new byte[DataStream.Length - DataStream.Position];
DataStream.Read(VerifierBytes, VerifierBytes.Length);
TStandardEncryptionVerifier Verifier = ReadStandardVerifier(VerifierBytes);
TEncryptionKey Key = new TStandardEncryptionKey(ReadStandardSalt(VerifierBytes), (int)KeyBits / 8);
CheckPassword(Encryption, Verifier, EncParams, Key);
return(DecryptStream(DataStream, EncParams, Key));
}
