public static string Decrypt(string password, string data)
{
SJCLBlob ctdata = JsonConvert.DeserializeObject <SJCLBlob>(data);
if (ctdata.Cipher != "aes" || ctdata.Mode != "ccm")
{
throw new InvalidOperationException("Unsupported cipher or mode.");
}
byte[] cipherText = DecodeBase64(ctdata.CipherText);
var derivedMacParameters = DeriveKey(password, ctdata);
var l = FindIVLen(cipherText.Length);
byte[] iv = new byte[l];
Array.Copy((Array)DecodeBase64(ctdata.IV), (Array)iv, (int)l);
var ccmparams = new CcmParameters(derivedMacParameters, ctdata.TagSize, iv, DecodeBase64(ctdata.AuthData));
var ccmMode = new CcmBlockCipher(new AesFastEngine());
ccmMode.Init(false, ccmparams);
var plainBytes = new byte[ccmMode.GetOutputSize(cipherText.Length)];
var res = ccmMode.ProcessBytes(cipherText, 0, cipherText.Length, plainBytes, 0);
ccmMode.DoFinal(plainBytes, res);
return(Encoding.UTF8.GetString(plainBytes));
}
private static KeyParameter DeriveKey(string password, SJCLBlob ctdata)
{
var kdf = new Pkcs5S2Sha256ParametersGenerator();
kdf.Init(Encoding.UTF8.GetBytes(password), DecodeBase64(ctdata.Salt), ctdata.Iterations);
var derivedMacParameters = (KeyParameter)kdf.GenerateDerivedMacParameters(ctdata.KeySize);
return(derivedMacParameters);
}
public static string Encrypt(string password, string data)
{
RNGCryptoServiceProvider rngCsp = new RNGCryptoServiceProvider();
byte[] salt = new byte[8];
rngCsp.GetBytes(salt);
byte[] iv = new byte[16];
rngCsp.GetBytes(iv);
SJCLBlob ctdata = new SJCLBlob()
{
Mode = "ccm",
Cipher = "aes",
AuthData = "",
Iterations = 2000,
KeySize = 256,
TagSize = 64,
Salt = Convert.ToBase64String(salt),
IV = Convert.ToBase64String(iv),
V = 1
};
var key = DeriveKey(password, ctdata);
byte[] rawdata = Encoding.UTF8.GetBytes(data);
var l = FindIVLen(rawdata.Length);
byte[] civ = new byte[l];
Array.Copy((Array)iv, (Array)civ, (int)l);
var ccmparams = new CcmParameters(key, ctdata.TagSize, civ, DecodeBase64(ctdata.AuthData));
var ccmMode = new CcmBlockCipher(new AesFastEngine());
ccmMode.Init(true, ccmparams);
var encBytes = new byte[ccmMode.GetOutputSize(rawdata.Length)];
var res = ccmMode.ProcessBytes(rawdata, 0, rawdata.Length, encBytes, 0);
ccmMode.DoFinal(encBytes, res);
ctdata.CipherText = Convert.ToBase64String(encBytes);
return(JsonConvert.SerializeObject(ctdata));
}
private static KeyParameter DeriveKey(string password, SJCLBlob ctdata)
{
var kdf = new Pkcs5S2Sha256ParametersGenerator();
kdf.Init(Encoding.UTF8.GetBytes(password), DecodeBase64(ctdata.Salt), ctdata.Iterations);
var derivedMacParameters = (KeyParameter) kdf.GenerateDerivedMacParameters(ctdata.KeySize);
return derivedMacParameters;
}
public static string Encrypt(string password, string data)
{
RNGCryptoServiceProvider rngCsp = new RNGCryptoServiceProvider();
byte[] salt = new byte[8];
rngCsp.GetBytes(salt);
byte[] iv = new byte[16];
rngCsp.GetBytes(iv);
SJCLBlob ctdata = new SJCLBlob()
{
Mode = "ccm",
Cipher = "aes",
AuthData = "",
Iterations = 2000,
KeySize = 256,
TagSize = 64,
Salt = Convert.ToBase64String(salt),
IV = Convert.ToBase64String(iv),
V = 1
};
var key = DeriveKey(password, ctdata);
byte[] rawdata = Encoding.UTF8.GetBytes(data);
var l = FindIVLen(rawdata.Length);
byte[] civ = new byte[l];
Array.Copy((Array) iv, (Array) civ, (int) l);
var ccmparams = new CcmParameters(key, ctdata.TagSize, civ, DecodeBase64(ctdata.AuthData));
var ccmMode = new CcmBlockCipher(new AesFastEngine());
ccmMode.Init(true, ccmparams);
var encBytes = new byte[ccmMode.GetOutputSize(rawdata.Length)];
var res = ccmMode.ProcessBytes(rawdata, 0, rawdata.Length, encBytes, 0);
ccmMode.DoFinal(encBytes, res);
ctdata.CipherText = Convert.ToBase64String(encBytes);
return JsonConvert.SerializeObject(ctdata);
}
