private static void VerifyDecryptKeyExchange(
AsymmetricKeyExchangeFormatter formatter,
AsymmetricKeyExchangeDeformatter deformatter)
{
byte[] encrypted = formatter.CreateKeyExchange(TestData.HelloBytes);
byte[] decrypted = deformatter.DecryptKeyExchange(encrypted);
Assert.Equal(TestData.HelloBytes, decrypted);
encrypted[encrypted.Length - 1] ^= 0xff;
try
{
byte[] invalidMessage = deformatter.DecryptKeyExchange(encrypted);
// RSAEncryptionPadding.Pkcs1 has loose integrity checking, recognizing ~1/110000
// messages as decryptable. So we only have a logic problem in our code if we produce
// the original input again. (The odds of a random payload producing "Hello" for a
// 2048-bit key are 1 in 49 quintillion (4.869e19)).
//
// Since we're basing "invalid" off of "valid" the odds will be different than true
// random, but it's not obvious if they're better or worse.
if (invalidMessage.SequenceEqual(TestData.HelloBytes))
{
string msg = $"Decrypt was unexpectedly successful: {encrypted.ByteArrayToHex()}";
// Just in case the exception text gets trimmed from test logs, Console.WriteLine it.
Console.WriteLine(msg);
throw new InvalidOperationException(msg);
}
}
catch (CryptographicException)
{
// Equivalent to Assert.ThrowsAny<CryptographicException>
}
}
private static void VerifyDecryptKeyExchange(AsymmetricKeyExchangeFormatter formatter, AsymmetricKeyExchangeDeformatter deformatter)
{
byte[] encrypted = formatter.CreateKeyExchange(TestData.HelloBytes);
byte[] decrypted = deformatter.DecryptKeyExchange(encrypted);
Assert.Equal(TestData.HelloBytes, decrypted);
encrypted[encrypted.Length - 1] ^= 0xff;
Assert.ThrowsAny<CryptographicException>(() => deformatter.DecryptKeyExchange(encrypted));
}
private static void VerifyDecryptKeyExchange(AsymmetricKeyExchangeFormatter formatter, AsymmetricKeyExchangeDeformatter deformatter)
{
byte[] encrypted = formatter.CreateKeyExchange(TestData.HelloBytes);
byte[] decrypted = deformatter.DecryptKeyExchange(encrypted);
Assert.Equal(TestData.HelloBytes, decrypted);
encrypted[encrypted.Length - 1] ^= 0xff;
Assert.ThrowsAny <CryptographicException>(() => deformatter.DecryptKeyExchange(encrypted));
}
public static byte[] EncryptKey(byte[] keyData, RSA rsa, bool fOAEP)
{
AsymmetricKeyExchangeFormatter formatter = null;
if (fOAEP)
{
formatter = new RSAOAEPKeyExchangeFormatter(rsa);
}
else
{
formatter = new RSAPKCS1KeyExchangeFormatter(rsa);
}
return(formatter.CreateKeyExchange(keyData));
}
public static bool TestKeyExchange(AsymmetricKeyExchangeFormatter f, AsymmetricKeyExchangeDeformatter d, bool expct)
{
bool bRes = true;
Random rnd = new Random();
int len = rnd.Next(12) + 5;
byte[] data = new byte[len];
byte[] exc = f.CreateKeyExchange(data);
byte[] exct = f.CreateKeyExchange(data, typeof(RC2CryptoServiceProvider));
try
{
byte[] res = d.DecryptKeyExchange(exc);
byte[] rest = d.DecryptKeyExchange(exct);
if (!Compare(res, data))
{
Console.WriteLine("KeyExchangeFormatter/Deformatter failed to roundtrip #1");
bRes = false;
}
if (!Compare(rest, data))
{
Console.WriteLine("KeyExchangeFormatter/Deformatter failed to roundtrip #2");
bRes = false;
}
}
catch (CryptographicException e)
{
Console.Write("EXCEPTION: " + e.Message);
bRes = false;
}
bRes = (bRes == expct);
if (bRes)
{
Console.WriteLine("OK (expct was " + expct + ")");
}
else
{
Console.WriteLine("FAIL (expct was " + expct + ")");
}
return(bRes);
}
public byte[] Encrypt(byte[] rgb, bool fOAEP)
{
// choose between OAEP or PKCS#1 v.1.5 padding
AsymmetricKeyExchangeFormatter fmt = null;
if (fOAEP)
{
fmt = new RSAOAEPKeyExchangeFormatter(rsa);
}
else
{
fmt = new RSAPKCS1KeyExchangeFormatter(rsa);
}
return(fmt.CreateKeyExchange(rgb));
}
public static bool TestKeyExchange(AsymmetricKeyExchangeFormatter f, AsymmetricKeyExchangeDeformatter d, bool expct)
{
bool bRes = true;
Random rnd = new Random();
int len = rnd.Next(12)+5;
byte[] data = new byte[len];
byte[] exc = f.CreateKeyExchange(data);
byte[] exct = f.CreateKeyExchange(data, typeof(RC2CryptoServiceProvider));
try
{
byte[] res = d.DecryptKeyExchange(exc);
byte[] rest = d.DecryptKeyExchange(exct);
if (!Compare(res, data))
{
Console.WriteLine("KeyExchangeFormatter/Deformatter failed to roundtrip #1");
bRes = false;
}
if (!Compare(rest, data))
{
Console.WriteLine("KeyExchangeFormatter/Deformatter failed to roundtrip #2");
bRes = false;
}
}
catch(CryptographicException e)
{
Console.Write("EXCEPTION: " + e.Message);
bRes = false;
}
bRes = (bRes==expct);
if (bRes)
Console.WriteLine("OK (expct was " + expct + ")");
else
Console.WriteLine("FAIL (expct was " + expct + ")");
return bRes;
}
private static void InvalidFormatterArguments(AsymmetricKeyExchangeFormatter formatter)
{
Assert.Throws <ArgumentNullException>(() => formatter.SetKey(null));
Assert.Throws <CryptographicUnexpectedOperationException>(() => formatter.CreateKeyExchange(new byte[] { 0, 1, 2, 3 }));
}
private static void InvalidFormatterArguments(AsymmetricKeyExchangeFormatter formatter)
{
Assert.Throws<ArgumentNullException>(() => formatter.SetKey(null));
Assert.Throws<CryptographicUnexpectedOperationException>(() => formatter.CreateKeyExchange(new byte[] { 0, 1, 2, 3 }));
}