// methods
private void Decode(byte[] data)
{
ASN1 encryptedPrivateKeyInfo = new ASN1(data);
if (encryptedPrivateKeyInfo.Tag != 0x30)
{
throw new CryptographicException("invalid EncryptedPrivateKeyInfo");
}
ASN1 encryptionAlgorithm = encryptedPrivateKeyInfo[0];
if (encryptionAlgorithm.Tag != 0x30)
{
throw new CryptographicException("invalid encryptionAlgorithm");
}
ASN1 algorithm = encryptionAlgorithm[0];
if (algorithm.Tag != 0x06)
{
throw new CryptographicException("invalid algorithm");
}
_algorithm = ASN1Convert.ToOid(algorithm);
// parameters ANY DEFINED BY algorithm OPTIONAL
if (encryptionAlgorithm.Count > 1)
{
ASN1 parameters = encryptionAlgorithm[1];
if (parameters.Tag != 0x30)
{
throw new CryptographicException("invalid parameters");
}
ASN1 salt = parameters[0];
if (salt.Tag != 0x04)
{
throw new CryptographicException("invalid salt");
}
_salt = salt.Value;
ASN1 iterationCount = parameters[1];
if (iterationCount.Tag != 0x02)
{
throw new CryptographicException("invalid iterationCount");
}
_iterations = ASN1Convert.ToInt32(iterationCount);
}
ASN1 encryptedData = encryptedPrivateKeyInfo[1];
if (encryptedData.Tag != 0x04)
{
throw new CryptographicException("invalid EncryptedData");
}
_data = encryptedData.Value;
}
// methods
private void Decode(byte[] data)
{
ASN1 privateKeyInfo = new ASN1(data);
if (privateKeyInfo.Tag != 0x30)
{
throw new CryptographicException("invalid PrivateKeyInfo");
}
ASN1 version = privateKeyInfo[0];
if (version.Tag != 0x02)
{
throw new CryptographicException("invalid version");
}
_version = version.Value[0];
ASN1 privateKeyAlgorithm = privateKeyInfo[1];
if (privateKeyAlgorithm.Tag != 0x30)
{
throw new CryptographicException("invalid algorithm");
}
ASN1 algorithm = privateKeyAlgorithm[0];
if (algorithm.Tag != 0x06)
{
throw new CryptographicException("missing algorithm OID");
}
_algorithm = ASN1Convert.ToOid(algorithm);
ASN1 privateKey = privateKeyInfo[2];
_key = privateKey.Value;
// attributes [0] IMPLICIT Attributes OPTIONAL
if (privateKeyInfo.Count > 3)
{
ASN1 attributes = privateKeyInfo[3];
for (int i = 0; i < attributes.Count; i++)
{
_list.Add(attributes[i]);
}
}
}
public static RSAParameters DecodePkcs8PublicKey(byte[] pkcs8blob)
{
// See: http://tools.ietf.org/html/rfc5280
// http://www.cryptopp.com/wiki/Keys_and_Formats#Dumping_PKCS_.238_and_X.509_Keys
//
// SubjectPublicKeyInfo ::= SEQUENCE {
// algorithm AlgorithmIdentifier,
// subjectPublicKey BIT STRING }
ASN1 publicKeyInfo = new ASN1(pkcs8blob);
if (publicKeyInfo.Tag != 0x30)
{
throw new CryptographicException("invalid PublicKeyInfo");
}
ASN1 keyAlgorithm = publicKeyInfo[0];
if (keyAlgorithm.Tag != 0x30)
{
throw new CryptographicException("invalid algorithm");
}
ASN1 algorithm = keyAlgorithm[0];
if (algorithm.Tag != 0x06)
{
throw new CryptographicException("missing algorithm OID");
}
if (ASN1Convert.ToOid(algorithm) != Oid.rsaEncryption)
{
throw new NotSupportedException("Only RSA keys are currently supported.");
}
var keyBits = publicKeyInfo[1];
if (keyBits.Tag != 0x03)
{
throw new CryptographicException("Invalid or corrupted key container, expecint a BIT STRING, found tag: " + keyBits.Tag);
}
var sanitizedKeyBits = RemoveLeadingZero(keyBits.Value);
return(DecodeAsn1RsaPublicKey(new ASN1(sanitizedKeyBits)));
}
