private byte[] SignHashInternal(
byte[] hash
, Org.BouncyCastle.Crypto.IDigest digest
, bool asOaep
)
{
byte[] derEncoded = this.DerEncode(hash, digest);
Org.BouncyCastle.Crypto.IAsymmetricBlockCipher rsaEngine = null;
if (asOaep) // PSS:
{
rsaEngine =
new Org.BouncyCastle.Crypto.Encodings.OaepEncoding(
new Org.BouncyCastle.Crypto.Engines.RsaBlindedEngine()
);
}
else // Pkcs1
{
rsaEngine =
new Org.BouncyCastle.Crypto.Encodings.Pkcs1Encoding(
new Org.BouncyCastle.Crypto.Engines.RsaBlindedEngine()
);
}
rsaEngine.Init(true, this.m_keyPair.Private);
byte[] encoded = rsaEngine.ProcessBlock(derEncoded, 0, derEncoded.Length);
return(encoded);
} // End Function SignHashInternal
private byte[] DecryptInternal(byte[] bytesToDecrypt, bool asOaep)
{
if (bytesToDecrypt == null)
{
throw new System.ArgumentNullException(nameof(bytesToDecrypt));
}
if (bytesToDecrypt.Length > this.KeySize / 8)
{
throw new System.Security.Cryptography.CryptographicException(
$"Padding: data too big - key size in bytes: \"{System.Convert.ToString(this.KeySize / 8)}\".");
}
Org.BouncyCastle.Crypto.IAsymmetricBlockCipher decryptionEngine = null;
if (asOaep)
{
//Org.BouncyCastle.Crypto.Encodings.OaepEncoding decryptionEngine =
decryptionEngine = new Org.BouncyCastle.Crypto.Encodings.OaepEncoding(new Org.BouncyCastle.Crypto.Engines.RsaEngine());
}
else
{
// Org.BouncyCastle.Crypto.Encodings.Pkcs1Encoding decryptionEngine =
decryptionEngine = new Org.BouncyCastle.Crypto.Encodings.Pkcs1Encoding(new Org.BouncyCastle.Crypto.Engines.RsaEngine());
}
decryptionEngine.Init(false, m_keyParameter);
return(decryptionEngine.ProcessBlock(bytesToDecrypt, 0, bytesToDecrypt.Length));
} // End Function DecryptInternal
public byte[] Decrypt(byte[] encryptedData)
{
encryptedData.ThrowIfNull(nameof(encryptedData));
if (encryptEngine == null)
{
var encryptEngineTemp = new Org.BouncyCastle.Crypto.Encodings.OaepEncoding(new Org.BouncyCastle.Crypto.Engines.RsaEngine(), new Org.BouncyCastle.Crypto.Digests.Sha256Digest());
Org.BouncyCastle.OpenSsl.PemReader pr =
new Org.BouncyCastle.OpenSsl.PemReader(
new System.IO.StringReader(privateKey));
Org.BouncyCastle.Crypto.AsymmetricCipherKeyPair keyParametersPrivate
= (Org.BouncyCastle.Crypto.AsymmetricCipherKeyPair)pr.ReadObject();
encryptEngineTemp.Init(false, keyParametersPrivate.Private);
encryptEngine = encryptEngineTemp;
}
return(encryptEngine.ProcessBlock(encryptedData, 0, encryptedData.Length));
}
private byte[] EncryptInternal(byte[] bytesToEncrypt, bool asOaep)
{
if (bytesToEncrypt == null)
{
throw new System.ArgumentNullException(nameof(bytesToEncrypt));
}
Org.BouncyCastle.Crypto.IAsymmetricBlockCipher encryptEngine = null;
if (asOaep)
{
//Org.BouncyCastle.Crypto.Encodings.OaepEncoding encryptEngine =
encryptEngine = new Org.BouncyCastle.Crypto.Encodings.OaepEncoding(new Org.BouncyCastle.Crypto.Engines.RsaEngine());
}
else
{
// Org.BouncyCastle.Crypto.Encodings.Pkcs1Encoding encryptEngine =
encryptEngine = new Org.BouncyCastle.Crypto.Encodings.Pkcs1Encoding(new Org.BouncyCastle.Crypto.Engines.RsaEngine());
}
encryptEngine.Init(true, this.m_keyParameter);
return(encryptEngine.ProcessBlock(bytesToEncrypt, 0, bytesToEncrypt.Length));
} // End Function EncryptInternal
private bool VerifyHashInternal(
byte[] hash
, byte[] signature
, Org.BouncyCastle.Crypto.IDigest digest
, bool asOaep)
{
Org.BouncyCastle.Crypto.IAsymmetricBlockCipher rsaEngine = null;
if (asOaep) // PSS:
{
rsaEngine =
new Org.BouncyCastle.Crypto.Encodings.OaepEncoding(
new Org.BouncyCastle.Crypto.Engines.RsaBlindedEngine()
);
}
else // Pkcs1
{
rsaEngine =
new Org.BouncyCastle.Crypto.Encodings.Pkcs1Encoding(
new Org.BouncyCastle.Crypto.Engines.RsaBlindedEngine()
);
}
rsaEngine.Init(false, this.m_keyPair.Public);
byte[] a = null;
byte[] b = null;
try
{
a = rsaEngine.ProcessBlock(signature, 0, signature.Length);
b = this.DerEncode(hash, digest);
}
catch
{
return(false);
}
if (a.Length == b.Length)
{
return(Org.BouncyCastle.Utilities.Arrays.ConstantTimeAreEqual(a, b));
}
if (a.Length != b.Length - 2)
{
return(false);
}
int num1 = a.Length - hash.Length - 2;
int num2 = b.Length - hash.Length - 2;
b[1] -= (byte)2;
b[3] -= (byte)2;
int num3 = 0;
for (int index = 0; index < hash.Length; ++index)
{
num3 |= (int)a[num1 + index] ^ (int)b[num2 + index];
}
for (int index = 0; index < num1; ++index)
{
num3 |= (int)a[index] ^ (int)b[index];
}
return(num3 == 0);
} // End Function VerifyHashInternal
