/// <summary>
/// Returns <paramref name="data"/> decrypted based on encryption original <paramref name="stringFormat"/>, <paramref name="key"/> and <paramref name="encryptionProvider"/>.
/// </summary>
public static string Decrypt(string data, string key, EncryptionProvider encryptionProvider, StringFormat stringFormat)
{
Argument.IsNotNull(data, "data");
Argument.IsNotNull(key, "key");
var encryptionAlgorithm = GetEncryptionAlgorithm(encryptionProvider);
var dataBytes = Util.StringToBytes(data, stringFormat, defaultEncoding).ToArray();
encryptionAlgorithm.Key = CreateCryptoKey(encryptionAlgorithm, key);
encryptionAlgorithm.IV = CreateCryptoIv(encryptionAlgorithm, DefaultInitializationVector);
var result = new byte[dataBytes.Length];
using (var ms = new MemoryStream(dataBytes, 0, dataBytes.Length))
{
using (var cs = new CryptoStream(ms, encryptionAlgorithm.CreateDecryptor(), CryptoStreamMode.Read))
{
cs.Read(result, 0, dataBytes.Length);
}
}
// Clean trailing zeros.
result = Util.CleanBytes(result).ToArray();
return Util.BytesToTextString(result, defaultEncoding);
}
/// <summary>
/// Returns <paramref name="data"/> encrypted in target <paramref name="stringFormat"/> based on <paramref name="key"/> and <paramref name="encryptionProvider"/>.
/// </summary>
public static string Encrypt(string data, string key, EncryptionProvider encryptionProvider, StringFormat stringFormat)
{
Argument.IsNotNull(data, "data");
Argument.IsNotNull(key, "key");
var encryptionAlgorithm = GetEncryptionAlgorithm(encryptionProvider);
var dataBytes = defaultEncoding.GetBytes(data);
encryptionAlgorithm.Key = CreateCryptoKey(encryptionAlgorithm, key);
encryptionAlgorithm.IV = CreateCryptoIv(encryptionAlgorithm, DefaultInitializationVector);
string result;
using (var ms = new MemoryStream())
{
using (var cs = new CryptoStream(ms, encryptionAlgorithm.CreateEncryptor(), CryptoStreamMode.Write))
{
cs.Write(dataBytes, 0, dataBytes.Length);
}
result = Util.BytesToString(ms.ToArray(), stringFormat);
}
return result;
}
internal static string GetAuthorizationToken(string username, string password)
{
//getting public key
try {
System.Net.ServicePointManager.Expect100Continue = false;
HttpWebRequest request = (HttpWebRequest) WebRequest.Create (auth_key_uri);
HttpWebResponse response = (HttpWebResponse) request.GetResponse ();
XPathNavigator navigator = (new XPathDocument (new StreamReader (
response.GetResponseStream ()))).CreateNavigator ();
string public_key = (string) navigator.Evaluate ("string(/response/key)");
string request_id = (string) navigator.Evaluate ("string(/response/request_id)");
response.Close ();
//encoding
EncryptionProvider encryption_provider = new EncryptionProvider ();
encryption_provider.ImportPublicKey (public_key);
string credentials = String.Format (@"<credentials login=""{0}"" password=""{1}""/>", username, password);
string encoded_credentials = Convert.ToBase64String (encryption_provider.Encrypt
(new UTF8Encoding ().GetBytes (credentials)));
//sending encoded data and receiving authorization token
request = (HttpWebRequest) WebRequest.Create (auth_token_uri);
request.Method = "POST";
request.ContentType = "application/x-www-form-urlencoded";
byte[] parameters = Encoding.UTF8.GetBytes ("request_id=" +
request_id + "&credentials=" + HttpUtility.UrlEncode(encoded_credentials));
Stream request_stream = request.GetRequestStream ();
request_stream.Write (parameters, 0, parameters.Length);
request_stream.Close ();
response = (HttpWebResponse) request.GetResponse ();
navigator = (new XPathDocument (new StreamReader (
response.GetResponseStream ()))).CreateNavigator ();
string token = (string) navigator.Evaluate ("string(/response/token)");
response.Close ();
return token;
} catch (WebException exception) {
HttpWebResponse response = (HttpWebResponse) exception.Response;
if (response != null) {
string response_text;
HttpStatusCode status_code = response.StatusCode;
using (StreamReader reader = new StreamReader (response.GetResponseStream ())) {
response_text = reader.ReadToEnd ();
}
//Process 403 and 400 errors
if (status_code == HttpStatusCode.Forbidden || status_code == HttpStatusCode.BadRequest) {
XmlDocument document = new XmlDocument ();
document.LoadXml (response_text);
XPathNavigator navigator = document.CreateNavigator ();
string error = (string) navigator.Evaluate ("string(//error)");
throw new AuthenticationFailedException (error);
}
}
throw new ConnectionFailedException (exception.Message);
}
}
private static SymmetricAlgorithm GetEncryptionAlgorithm(EncryptionProvider encryptionProvider)
{
switch (encryptionProvider)
{
case EncryptionProvider.Des:
return new DESCryptoServiceProvider();
case EncryptionProvider.Rc2:
return new RC2CryptoServiceProvider();
case EncryptionProvider.Rijndael:
return new RijndaelManaged();
case EncryptionProvider.TripleDes:
return new TripleDESCryptoServiceProvider();
}
throw new InvalidEnumArgumentException(string.Format("Not supported encryption provider: {0}", encryptionProvider));
}
