public string Decrypt(string encrypted)
{
string res = "";
try
{
if (encrypted == null)
{
return("");
}
if (encrypted.Trim().Length == 0)
{
return("");
}
// base 64 decode
byte[] encryptedBytesWithSalt = Convert.FromBase64String(encrypted);
// extract salt (first 8 bytes of encrypted)
byte[] salt = new byte[8];
byte[] encryptedBytes = new byte[encryptedBytesWithSalt.Length - salt.Length - 8];
Buffer.BlockCopy(encryptedBytesWithSalt, 8, salt, 0, salt.Length);
Buffer.BlockCopy(encryptedBytesWithSalt, salt.Length + 8, encryptedBytes, 0, encryptedBytes.Length);
// get key and iv
byte[] key, iv;
DeriveKeyAndIV(passphrase, salt, out key, out iv);
res = DecryptStringFromBytesAes(encryptedBytes, key, iv);
res = Uri.UnescapeDataString(res);
}
catch (Exception exp)
{
clsEcom common = new clsEcom();
common.Log("Decrypt", exp.Message + "(value=" + encrypted + ")", true, exp);
}
return(res);
}
public bool IsContainsSpecialChars(string val)
{
bool res = false;
try
{
if (val.ToLower().Trim().Contains("'"))
{
return(true);
}
if (val.ToLower().Trim().Contains('"'))
{
return(true);
}
if (val.ToLower().Trim().Contains("&"))
{
return(true);
}
if (val.ToLower().Trim().Contains("--"))
{
return(true);
}
}
catch (Exception exp)
{
clsEcom clsecom = new clsEcom();
clsecom.Log("IsContainsSpecialChars", exp.Message + "(val=" + val + ")", true, exp, false);
}
return(res);
}
public bool AuthToken(string token, string device_id)
{
clsEcomEncryptor enc = new clsEcomEncryptor();
clsEcom clsecom = new clsEcom();
string res = clsecom.get_value(token);
if (res.Trim().Length == 0)
{
return(false);
}
res = enc.Encrypt(res);
if (res.Trim().Length == 0)
{
return(false);
}
string[] splt = res.Split(',');
if (splt.Length != 3)
{
return(false);
}
if (splt[2] != additional_key)
{
return(false);
}
string device_id_token = splt[1];
if (device_id != device_id_token)
{
return(false);
}
DateTime date1 = DateTime.Now;
if (!DateTime.TryParse(splt[0], out date1))
{
return(false);
}
TimeSpan ts = (TimeSpan)(DateTime.Now - date1);
if (ts.TotalDays > 30)
{
return(false);
}
return(true);
}
public string Encrypt(string plainText)
{
string res = "";
try
{
if (plainText == null)
{
return("");
}
if (plainText.Trim().Length == 0)
{
return("");
}
// generate salt
byte[] key, iv;
byte[] salt = new byte[8];
RNGCryptoServiceProvider rng = new RNGCryptoServiceProvider();
rng.GetNonZeroBytes(salt);
DeriveKeyAndIV(passphrase, salt, out key, out iv);
// encrypt bytes
byte[] encryptedBytes = EncryptStringToBytesAes(plainText, key, iv);
// add salt as first 8 bytes
byte[] encryptedBytesWithSalt = new byte[salt.Length + encryptedBytes.Length + 8];
Buffer.BlockCopy(Encoding.ASCII.GetBytes("Salted__"), 0, encryptedBytesWithSalt, 0, 8);
Buffer.BlockCopy(salt, 0, encryptedBytesWithSalt, 8, salt.Length);
Buffer.BlockCopy(encryptedBytes, 0, encryptedBytesWithSalt, salt.Length + 8, encryptedBytes.Length);
// base64 encode
res = Convert.ToBase64String(encryptedBytesWithSalt);
res = Uri.EscapeUriString(res);
}
catch (Exception exp)
{
clsEcom common = new clsEcom();
common.Log("Encrypt", exp.Message + "(value=" + plainText + ")", true, exp);
}
return(res);
}
