public override void Decode(Asn1BerDecodeBuffer buffer, bool explicitTagging, int implicitLength)
{
var elemLength = explicitTagging ? MatchTag(buffer, Asn1Tag.Sequence) : implicitLength;
Init();
var context = new Asn1BerDecodeContext(buffer, elemLength);
var parsedLen = new IntHolder();
if (!context.MatchElemTag(0, 0, ObjectIdentifierTypeCode, parsedLen, false))
{
throw ExceptionUtility.CryptographicException(Resources.Asn1MissingRequiredException, buffer.ByteCount);
}
EncryptionParamSet = new Gost2814789ParamSet();
EncryptionParamSet.Decode(buffer, true, parsedLen.Value);
if (context.MatchElemTag(0x80, 0x20, EocTypeCode, parsedLen, true))
{
EphemeralPublicKey = new SubjectPublicKeyInfo();
EphemeralPublicKey.Decode(buffer, false, parsedLen.Value);
}
if (!context.MatchElemTag(0, 0, OctetStringTypeCode, parsedLen, false))
{
throw ExceptionUtility.CryptographicException(Resources.Asn1MissingRequiredException, buffer.ByteCount);
}
Ukm = new Asn1OctetString();
Ukm.Decode(buffer, true, parsedLen.Value);
if (Ukm.Length != 8)
{
throw ExceptionUtility.CryptographicException(Resources.Asn1ConsVioException, "Ukm.Length", Ukm.Length);
}
}
private static SubjectPublicKeyInfo EncodePublicKey(GostKeyExchangeParameters transportParameters)
{
var asnEncoder = new Asn1BerEncodeBuffer();
var publicKey = new Asn1OctetString(transportParameters.PublicKey);
publicKey.Encode(asnEncoder);
var publicKeyValue = asnEncoder.MsgCopy;
var publicKeyInfo = new SubjectPublicKeyInfo
{
SubjectPublicKey = new Asn1BitString(publicKeyValue.Length * 8, publicKeyValue)
};
var publicKeyParams = new GostR34102001PublicKeyParameters
{
PublicKeyParamSet = Asn1ObjectIdentifier.FromOidString(transportParameters.PublicKeyParamSet),
DigestParamSet = Asn1ObjectIdentifier.FromOidString(transportParameters.DigestParamSet),
EncryptionParamSet = CreateEncryptionParamSet(transportParameters.EncryptionParamSet)
};
asnEncoder.Reset();
publicKeyParams.Encode(asnEncoder);
var publicKeyAlgOid = new Asn1ObjectIdentifier(GostR34102001Constants.IdGostR34102001);
publicKeyInfo.Algorithm = new AlgorithmIdentifier(publicKeyAlgOid, new Asn1OpenType(asnEncoder.MsgCopy));
return publicKeyInfo;
}
private void Init()
{
EncryptionParamSet = null;
EphemeralPublicKey = null;
Ukm = null;
}
