/// <summary>
/// Verify a request or response
/// </summary>
/// <param name="securityBuffers">Security buffers containing encrypted data.</param>
/// <param name="sentFromClient">True if the token is a request, false is a response</param>
/// <returns>True if verify succeed; otherwise, false.</returns>
private bool Verify(SecurityBuffer[] securityBuffers, bool sentFromClient)
{
KileContext context = sentFromClient ? (KileContext)kileDecoder.serverContext : (KileContext)kileDecoder.clientContext;
KilePdu pdu;
return(KileRole.GssVerifyMicEx(context, securityBuffers, out pdu));
}
/// <summary>
/// Encrypts Message. User decides what SecBuffers are used.
/// </summary>
/// <param name="kileRole">Represents client or server</param>
/// <param name="securityBuffers">The security buffers to encrypt.</param>
/// <exception cref="System.ArgumentException">Thrown when the data or token is not valid.</exception>
internal static void Encrypt(KileRole kileRole, params SecurityBuffer[] securityBuffers)
{
byte[] message = SspiUtility.ConcatenateReadWriteSecurityBuffers(securityBuffers, SecurityBufferType.Data);
byte[] token = SspiUtility.ConcatenateSecurityBuffers(securityBuffers, SecurityBufferType.Token);
if (token.Length == 0)
{
throw new ArgumentException("Token buffer is not valid.");
}
SGN_ALG sgnAlg = GetSgnAlg(kileRole);
KilePdu pdu = kileRole.GssWrap(true, sgnAlg, message);
byte[] cipherData = null;
if (pdu.GetType() == typeof(Token4121))
{
cipherData = pdu.ToBytes();
}
else
{
byte[] allData = pdu.ToBytes();
byte[] paddingData = ((Token1964_4757)pdu).paddingData;
cipherData = ArrayUtility.SubArray(allData, 0, allData.Length - paddingData.Length);
SspiUtility.UpdateSecurityBuffers(securityBuffers, SecurityBufferType.Padding, paddingData);
}
SspiUtility.UpdateSecurityBuffers(securityBuffers, SecurityBufferType.Data,
ArrayUtility.SubArray(cipherData, cipherData.Length - message.Length));
SspiUtility.UpdateSecurityBuffers(securityBuffers, SecurityBufferType.Token,
ArrayUtility.SubArray(cipherData, 0, cipherData.Length - message.Length));
}
/// <summary>
/// Decrypt a request or response
/// </summary>
/// <param name="securityBuffers">Security buffers containing encrypted data.</param>
/// <param name="sentFromClient">True if the token is a request, false is a response</param>
/// <returns>Plain-text data.</returns>
private byte[] Decrypt(SecurityBuffer[] securityBuffers, bool sentFromClient)
{
KileContext context = sentFromClient ? (KileContext)kileDecoder.serverContext : (KileContext)kileDecoder.clientContext;
KileRole.GssUnWrapEx(context, securityBuffers);
return(SspiUtility.ConcatenateReadWriteSecurityBuffers(securityBuffers, SecurityBufferType.Data));
}
/// <summary>
/// This takes the given SecurityBuffer array, signs data part, and updates signature into token part
/// </summary>
/// <param name="kileRole">Represents client or server</param>
/// <param name="securityBuffers">Data to sign and token to update.</param>
/// <exception cref="System.ArgumentException">Thrown when the data or token is not valid.</exception>
internal static void Sign(KileRole kileRole, params SecurityBuffer[] securityBuffers)
{
byte[] token = SspiUtility.ConcatenateReadWriteSecurityBuffers(securityBuffers, SecurityBufferType.Token);
if (token.Length == 0)
{
throw new ArgumentException("No token can be updated for signature.");
}
byte[] message = GetToBeSignedDataFromSecurityBuffers(securityBuffers);
SGN_ALG sgnAlg = GetSgnAlg(kileRole);
KilePdu pdu = kileRole.GssGetMic(sgnAlg, message);
byte[] signature = pdu.ToBytes();
SspiUtility.UpdateSecurityBuffers(securityBuffers, SecurityBufferType.Token, signature);
}
/// <summary>
/// Get SGN_ALG for encryption and sign.
/// </summary>
/// <returns>The SGN_ALG got from context.</returns>
/// <exception cref="System.FormatException">Thrown when the key is not valid.</exception>
private static SGN_ALG GetSgnAlg(KileRole kileRole)
{
EncryptionKey key = kileRole.Context.ContextKey;
if (key == null || key.keytype == null || key.keyvalue == null || key.keyvalue.Value == null)
{
throw new FormatException("Initialization is not complete successfully!");
}
SGN_ALG sgnAlg = SGN_ALG.HMAC;
EncryptionType type = (EncryptionType)key.keytype.Value;
if (type == EncryptionType.DES_CBC_MD5 || type == EncryptionType.DES_CBC_CRC)
{
sgnAlg = SGN_ALG.DES_MAC_MD5;
}
return(sgnAlg);
}
/// <summary>
/// This takes the given byte array, decrypts it, and returns
/// the original, unencrypted byte array.
/// </summary>
/// <param name="kileRole">Represents client or server</param>
/// <param name="securityBuffers">The security buffers to decrypt.</param>
/// <exception cref="System.ArgumentException">Thrown when the data or token is not valid.</exception>
internal static bool Decrypt(KileRole kileRole, params SecurityBuffer[] securityBuffers)
{
KilePdu pdu = kileRole.GssUnWrapEx(securityBuffers);
byte[] decryptedMessage = null;
if (pdu.GetType() == typeof(Token4121))
{
decryptedMessage = ((Token4121)pdu).Data;
}
else if (pdu.GetType() == typeof(Token1964_4757))
{
Token1964_4757 tokenData = (Token1964_4757)pdu;
decryptedMessage = tokenData.Data;
SspiUtility.UpdateSecurityBuffers(securityBuffers, SecurityBufferType.Padding, tokenData.paddingData);
}
// else do nothing
return(true);
}
/// <summary>
/// Decrypt a request or response
/// </summary>
/// <param name="token">A token containing encrypted data.</param>
/// <param name="sentFromClient">True if the token is a request, false is a response</param>
/// <returns>Plain-text data.</returns>
private byte[] Decrypt(byte[] token, bool sentFromClient)
{
KileContext context = sentFromClient ? (KileContext)kileDecoder.serverContext : (KileContext)kileDecoder.clientContext;
KilePdu pdu = KileRole.GssUnWrap(context, token);
Token4121 token4121Pdu = pdu as Token4121;
if (token4121Pdu != null)
{
return(token4121Pdu.Data);
}
Token1964_4757 token1964or4757Pdu = pdu as Token1964_4757;
if (token1964or4757Pdu != null)
{
return(token1964or4757Pdu.Data);
}
throw new InvalidOperationException("Token type is not supported.");
}
/// <summary>
/// Create a KileDecrypter instance.
/// User should call following methods in sequence to initialize: AsExchange, TgsExchange and ApExchange.
/// After exchanges are done, call DecryptRequest or DecryptResponse from first encrypted message to last.
/// Do not skip any request or response.
/// </summary>
/// <param name="domain">
/// The realm part of the client's principal identifier.
/// This argument cannot be null.
/// </param>
/// <param name="cName">
/// The account to logon the remote machine. Either user account or computer account.
/// This argument cannot be null.
/// </param>
/// <param name="password">
/// The password of the user.
/// This argument cannot be null.
/// </param>
/// <param name="accountType">
/// The type of the logon account. User or Computer.
/// </param>
/// <param name="connectionType">
/// The connection type, TCP or UDP.
/// </param>
/// <exception cref="System.ArgumentNullException">
/// Thrown when any parameter is null.
/// </exception>
public KileDecrypter(
string domain,
string cName,
string password,
KileAccountType accountType,
KileConnectionType connectionType)
{
if (domain == null)
{
throw new ArgumentNullException(nameof(domain));
}
if (cName == null)
{
throw new ArgumentNullException(nameof(cName));
}
if (password == null)
{
throw new ArgumentNullException(nameof(password));
}
kileDecoder = new KileDecoder();
kileDecoder.connectionType = connectionType;
string salt = KileRole.GenerateSalt(domain, cName, accountType);
kileDecoder.clientContext = new KileClientContext();
kileDecoder.clientContext.Password = password;
kileDecoder.clientContext.TransportType = connectionType;
kileDecoder.clientContext.Salt = salt;
kileDecoder.serverContext = new KileServerContext();
kileDecoder.serverContext.TransportType = connectionType;
kileDecoder.serverContext.Salt = salt;
kileDecoder.serverContextList = new Dictionary <KileConnection, KileServerContext>(new KileServerContextComparer());
kileDecoder.serverContextList.Add(new KileConnection(FAKE_ENDPOINT), kileDecoder.serverContext);
}
/// <summary>
/// This takes the given byte array and verifies it using the SSPI VerifySignature method.
/// </summary>
/// <param name="kileRole">Represents client or server</param>
/// <param name="securityBuffers">Data and token to verify</param>
/// <returns>Success if true, Fail if false</returns>
/// <exception cref="System.ArgumentException">Thrown when the data or token is not valid.</exception>
internal static bool Verify(KileRole kileRole, params SecurityBuffer[] securityBuffers)
{
KilePdu pdu;
return(kileRole.GssVerifyMicEx(securityBuffers, out pdu));
}
