/// <summary>
/// Encrypts a string of text into a Base64 string using the <see cref="RijndaelManaged" /> algorithm.
/// </summary>
/// <param name="input">The string to encrypt.</param>
public string EncryptString(string input)
{
if (string.IsNullOrEmpty(input))
{
return(input);
}
var data = Encoding.UTF8.GetBytes(input);
var key = EncryptionUtils.GenerateKey(Password, Salt.ToByteArray(), KeyIterations);
var seedBytes = Seed.ToByteArray();
var result = EncryptionUtils.Encrypt(data, key, seedBytes).EncryptedData;
return(Convert.ToBase64String(result));
}
// Client Constructor, username not needed, salt not generated by client
public SRP6(byte[] identityHash, String modulus_N, int generator_g,
String salt, string initialVector = "OFRna73m*aze01xY")
{
InitialVector = initialVector;
Modulus = BigIntegerExtension.Create(modulus_N, 16);
Generator = BigIntegerExtension.Create("" + generator_g, 10);
Multiplier = BigIntegerExtension.Create("3", 10);
Salt = BigIntegerExtension.Create(salt, 16);
// Client-side variables
PrivateKey = BigIntegerExtension.GeneratePseudoPrime(128, 100, new Random());
// g^a (mod N)
PublicKey = this.generator_g.modPow(privateKey, this.modulus_N);
// Server-side variables
SaltedIdentityHash = bytesToBig(Sha1Hash(Salt.ToByteArray(), identityHash));
}
/// <summary>
/// Decrypts the binary data of a Base64 string back into the original text using the <see
/// cref="RijndaelManaged" /> algorithm.
/// </summary>
/// <param name="input">The string to decrypt.</param>
public string DecryptString(string input)
{
if (string.IsNullOrEmpty(input))
{
return(input);
}
var encryptedData = Convert.FromBase64String(input);
var key = EncryptionUtils.GenerateKey(Password, Salt.ToByteArray(), KeyIterations);
var seedBytes = Seed.ToByteArray();
var decryptedData = EncryptionUtils.Decrypt(encryptedData, key, seedBytes);
using (var ms = new MemoryStream(decryptedData))
using (var sr = new StreamReader(ms))
{
return(sr.ReadToEnd());
}
}
public void Write(Stream stream)
{
using (var writer = new BinaryWriter(stream, Encoding.UTF8, true))
{
writer.Write((byte)AuthRequestOpcode.LogonChallenge);
writer.Write((byte)0);
writer.Write((byte)Result);
if (Result == AuthResponse.Success)
{
writer.Write(B.ToByteArray(32));
writer.Write(GLength);
writer.Write(G);
writer.Write(NLength);
writer.Write(N.ToByteArray(NLength));
writer.Write(Salt.ToByteArray(32));
writer.Write(RandomNumber.ToByteArray(16));
writer.Write(SecurityFlags);
}
}
}
