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public static RSAEP ( |
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| rsa | ||
| m | byte | |
| return | byte[] | |
public static byte[] Encrypt_OAEP(
RSA rsa,
HashAlgorithm hash,
RandomNumberGenerator rng,
byte[] M)
{
int size = rsa.KeySize / 8;
int maskLen = hash.HashSize / 8;
if (M.Length > size - 2 * maskLen - 2)
{
throw new CryptographicException("message too long");
}
byte[] emptyHash = PKCS1.GetEmptyHash(hash);
int num = size - M.Length - 2 * maskLen - 2;
byte[] array1 = new byte[emptyHash.Length + num + 1 + M.Length];
Buffer.BlockCopy((Array)emptyHash, 0, (Array)array1, 0, emptyHash.Length);
array1[emptyHash.Length + num] = (byte)1;
Buffer.BlockCopy((Array)M, 0, (Array)array1, array1.Length - M.Length, M.Length);
byte[] numArray1 = new byte[maskLen];
rng.GetBytes(numArray1);
byte[] array2_1 = PKCS1.MGF1(hash, numArray1, size - maskLen - 1);
byte[] mgfSeed = PKCS1.xor(array1, array2_1);
byte[] array2_2 = PKCS1.MGF1(hash, mgfSeed, maskLen);
byte[] numArray2 = PKCS1.xor(numArray1, array2_2);
byte[] x = new byte[numArray2.Length + mgfSeed.Length + 1];
Buffer.BlockCopy((Array)numArray2, 0, (Array)x, 1, numArray2.Length);
Buffer.BlockCopy((Array)mgfSeed, 0, (Array)x, numArray2.Length + 1, mgfSeed.Length);
byte[] m = PKCS1.OS2IP(x);
return(PKCS1.I2OSP(PKCS1.RSAEP(rsa, m), size));
}
public static byte[] Encrypt_OAEP(RSA rsa, HashAlgorithm hash, RandomNumberGenerator rng, byte[] M)
{
int num = rsa.KeySize / 8;
int num2 = hash.HashSize / 8;
if (M.Length > num - 2 * num2 - 2)
{
throw new CryptographicException("message too long");
}
byte[] emptyHash = PKCS1.GetEmptyHash(hash);
int num3 = num - M.Length - 2 * num2 - 2;
byte[] array = new byte[emptyHash.Length + num3 + 1 + M.Length];
Buffer.BlockCopy(emptyHash, 0, array, 0, emptyHash.Length);
array[emptyHash.Length + num3] = 1;
Buffer.BlockCopy(M, 0, array, array.Length - M.Length, M.Length);
byte[] array2 = new byte[num2];
rng.GetBytes(array2);
byte[] array3 = PKCS1.MGF1(hash, array2, num - num2 - 1);
byte[] array4 = PKCS1.xor(array, array3);
byte[] array5 = PKCS1.MGF1(hash, array4, num2);
byte[] array6 = PKCS1.xor(array2, array5);
byte[] array7 = new byte[array6.Length + array4.Length + 1];
Buffer.BlockCopy(array6, 0, array7, 1, array6.Length);
Buffer.BlockCopy(array4, 0, array7, array6.Length + 1, array4.Length);
byte[] m = PKCS1.OS2IP(array7);
byte[] x = PKCS1.RSAEP(rsa, m);
return(PKCS1.I2OSP(x, num));
}
public static byte[] Encrypt_v15(RSA rsa, RandomNumberGenerator rng, byte[] M)
{
int size = rsa.KeySize / 8;
if (M.Length > size - 11)
{
throw new CryptographicException("message too long");
}
int count = System.Math.Max(8, size - M.Length - 3);
byte[] data = new byte[count];
rng.GetNonZeroBytes(data);
byte[] x = new byte[size];
x[1] = (byte)2;
Buffer.BlockCopy((Array)data, 0, (Array)x, 2, count);
Buffer.BlockCopy((Array)M, 0, (Array)x, size - M.Length, M.Length);
byte[] m = PKCS1.OS2IP(x);
return(PKCS1.I2OSP(PKCS1.RSAEP(rsa, m), size));
}
public static byte[] Encrypt_v15(RSA rsa, RandomNumberGenerator rng, byte[] M)
{
int num = rsa.KeySize / 8;
if (M.Length > num - 11)
{
throw new CryptographicException("message too long");
}
int num2 = Math.Max(8, num - M.Length - 3);
byte[] array = new byte[num2];
rng.GetNonZeroBytes(array);
byte[] array2 = new byte[num];
array2[1] = 2;
Buffer.BlockCopy(array, 0, array2, 2, num2);
Buffer.BlockCopy(M, 0, array2, num - M.Length, M.Length);
byte[] m = PKCS1.OS2IP(array2);
byte[] x = PKCS1.RSAEP(rsa, m);
return(PKCS1.I2OSP(x, num));
}
