/// <summary>
/// Reads a packet from a stream.
/// </summary>
/// <param name="stream"> The stream. </param>
/// <returns> </returns>
internal static async Task<Frame> FromStream(Stream stream)
{
//read header
int read = 0;
var header = new byte[8];
while (read < 8)
read += await stream.ReadAsync(header, read, 8 - read).ConfigureAwait(false);
//get length
if (BitConverter.IsLittleEndian) Array.Reverse(header, 4, 4);
int length = BitConverter.ToInt32(header, 4);
Frame frame;
switch ((FrameOpcode)header[3])
{
case FrameOpcode.Error:
frame = new ErrorFrame();
break;
case FrameOpcode.Ready:
frame = new ReadyFrame();
break;
case FrameOpcode.Authenticate:
frame = new AuthenticateFrame();
break;
case FrameOpcode.Supported:
frame = new SupportedFrame();
break;
case FrameOpcode.Result:
frame = new ResultFrame();
break;
case FrameOpcode.Event:
frame = new EventFrame();
break;
default:
throw new ProtocolException(0, "Unexpected OpCode received.");
}
frame.Version = (FrameVersion)header[0];
frame.Flags = (FrameFlags)header[1];
frame.Stream = unchecked((sbyte)header[2]);
frame.OpCode = (FrameOpcode)header[3];
frame.Length = length;
//wrap the stream in a window, that will be completely read when disposed
var reader = new FrameReader(stream, length);
frame.Reader = reader;
//decompress the contents of the frame (implicity loads the entire frame body!)
if (frame.Flags.HasFlag(FrameFlags.Compression))
await reader.DecompressAsync();
//read tracing id if set
if (frame.Flags.HasFlag(FrameFlags.Tracing))
frame.TracingId = await reader.ReadUuidAsync().ConfigureAwait(false);
await frame.InitializeAsync().ConfigureAwait(false);
return frame;
}
/// <summary>
/// Authenticates the connection.
/// </summary>
/// <param name="auth">The authentication request from the server.</param>
/// <param name="logger">The logger.</param>
/// <returns></returns>
/// <exception cref="AuthenticationException">
/// Unsupported Authenticator: + auth.Authenticator;null
/// or
/// Authentication failed, SASL Challenge was rejected by client
/// or
/// Authentication failed, Authenticator rejected SASL result
/// or
/// Expected a Authentication Challenge from Server!
/// or
/// No credentials provided in configuration
/// or
/// Authentication failed: Ready frame not received
/// </exception>
private async Task AuthenticateAsync(AuthenticateFrame auth, Logger logger)
{
logger.LogVerbose("Authentication requested, attempting to provide credentials");
//dispose AuthenticateFrame
auth.Dispose();
if (auth.ProtocolVersion >= 2)
{
//protocol version2: use SASL AuthResponse to authenticate
//get an AuthenticatorFactory
IAuthenticatorFactory factory =
Loader.Extensions.AuthenticationFactories.FirstOrDefault(
f => f.Name.Equals(auth.Authenticator, StringComparison.OrdinalIgnoreCase));
if (factory == null)
throw new AuthenticationException(auth.ProtocolVersion, "Unsupported Authenticator: " + auth.Authenticator);
logger.LogVerbose("Attempting authentication for scheme {0}", factory.Name);
//grab an authenticator instance
IAuthenticator authenticator = factory.CreateAuthenticator(_config);
//start authentication loop
byte[] saslChallenge = null;
while (true)
{
//check for challenge
byte[] saslResponse;
if (!authenticator.Authenticate(auth.ProtocolVersion, saslChallenge, out saslResponse))
{
throw new AuthenticationException(auth.ProtocolVersion, "Authentication failed, SASL Challenge was rejected by client");
}
//send response
var cred = new AuthResponseFrame(saslResponse);
var authResponse =
await
SendRequestAsyncInternal(cred, logger, 1, CancellationToken.None).AutoConfigureAwait();
//dispose authResponse (makes sure all is read)
authResponse.Dispose();
//check for success
var success = authResponse as AuthSuccessFrame;
if (success != null)
{
if (!authenticator.Authenticate(auth.ProtocolVersion, success.SaslResult))
{
throw new AuthenticationException(authResponse.ProtocolVersion, "Authentication failed, Authenticator rejected SASL result", authResponse.TracingId);
}
//yeah, authenticated, break from the authentication loop
break;
}
//no success yet, lets try next round
var challenge = authResponse as AuthChallengeFrame;
if (challenge == null)
{
throw new AuthenticationException(authResponse.ProtocolVersion, "Expected a Authentication Challenge from Server!", authResponse.TracingId);
}
saslChallenge = challenge.SaslChallenge;
}
}
else
{
//protocol version1: use Credentials to authenticate
//check if _username is actually set
if (_config.Username == null || _config.Password == null)
throw new AuthenticationException(auth.ProtocolVersion, "No credentials provided in configuration");
var cred = new CredentialsFrame(_config.Username, _config.Password);
var authResponse =
await
SendRequestAsyncInternal(cred, logger, 1, CancellationToken.None).AutoConfigureAwait();
//dispose authResponse (makes sure all is read)
authResponse.Dispose();
if (!(authResponse is ReadyFrame))
{
throw new AuthenticationException(authResponse.ProtocolVersion, "Authentication failed: Ready frame not received", authResponse.TracingId);
}
}
}
/// <summary>
/// Reads a packet from a stream.
/// </summary>
/// <param name="stream"> The stream. </param>
/// <returns> </returns>
internal static async Task <Frame> FromStream(Stream stream)
{
//read header
int read = 0;
var header = new byte[8];
while (read < 8)
{
read += await stream.ReadAsync(header, read, 8 - read).ConfigureAwait(false);
}
//get length
if (BitConverter.IsLittleEndian)
{
Array.Reverse(header, 4, 4);
}
int length = BitConverter.ToInt32(header, 4);
Frame frame;
switch ((FrameOpcode)header[3])
{
case FrameOpcode.Error:
frame = new ErrorFrame();
break;
case FrameOpcode.Ready:
frame = new ReadyFrame();
break;
case FrameOpcode.Authenticate:
frame = new AuthenticateFrame();
break;
case FrameOpcode.Supported:
frame = new SupportedFrame();
break;
case FrameOpcode.Result:
frame = new ResultFrame();
break;
case FrameOpcode.Event:
frame = new EventFrame();
break;
default:
throw new ProtocolException(0, "Unexpected OpCode received.");
}
frame.Version = (FrameVersion)header[0];
frame.Flags = (FrameFlags)header[1];
frame.Stream = unchecked ((sbyte)header[2]);
frame.OpCode = (FrameOpcode)header[3];
frame.Length = length;
//wrap the stream in a window, that will be completely read when disposed
var reader = new FrameReader(stream, length);
frame.Reader = reader;
//decompress the contents of the frame (implicity loads the entire frame body!)
if (frame.Flags.HasFlag(FrameFlags.Compression))
{
await reader.DecompressAsync();
}
//read tracing id if set
if (frame.Flags.HasFlag(FrameFlags.Tracing))
{
frame.TracingId = await reader.ReadUuidAsync().ConfigureAwait(false);
}
await frame.InitializeAsync().ConfigureAwait(false);
return(frame);
}
/// <summary>
/// Gets the frame from opcode.
/// </summary>
/// <param name="protocolVersion">the version of the cql binary protocol in use</param>
/// <param name="opcode">The opcode.</param>
/// <returns></returns>
/// <exception cref="ProtocolException">Unexpected OpCode received.</exception>
private static Frame GetFrameFromOpcode(byte protocolVersion, FrameOpcode opcode)
{
Frame frame;
switch(opcode)
{
case FrameOpcode.Error:
frame = new ErrorFrame();
break;
case FrameOpcode.Ready:
frame = new ReadyFrame();
break;
case FrameOpcode.Authenticate:
frame = new AuthenticateFrame();
break;
case FrameOpcode.AuthChallenge:
frame = new AuthChallengeFrame();
break;
case FrameOpcode.AuthSuccess:
frame = new AuthSuccessFrame();
break;
case FrameOpcode.Supported:
frame = new SupportedFrame();
break;
case FrameOpcode.Result:
frame = new ResultFrame();
break;
case FrameOpcode.Event:
frame = new EventFrame();
break;
default:
throw new ProtocolException(protocolVersion, 0, string.Format("Unexpected OpCode {0:X} received.", opcode));
}
return frame;
}
