/// <summary>
/// Sends the handshake asynchronous.
/// </summary>
/// <param name="handshake">The handshake.</param>
/// <param name="cancellationToken">The cancellation token.</param>
/// <returns></returns>
public async Task <WebSocketResponseHandshake> SendHandshakeAsync(WebSocketRequestHandshake handshake, CancellationToken cancellationToken)
{
var oldState = Interlocked.CompareExchange(ref _state, WebSocketState.Opening, WebSocketState.Connected);
if (oldState != WebSocketState.Connected)
{
throw new InvalidOperationException(ErrorMessages.InvalidState + _state);
}
var data = handshake.ToString();
await this.SendAsync(data, Encoding.UTF8, cancellationToken);
var responseHeaders = new List <string>();
var line = await _tcp.ReadLineAsync(cancellationToken);
while (!String.IsNullOrEmpty(line))
{
responseHeaders.Add(line);
line = await _tcp.ReadLineAsync(cancellationToken);
}
var response = WebSocketResponseHandshake.Parse(responseHeaders);
if (response.StatusCode != HttpStatusCode.SwitchingProtocols)
{
var versions = response.SecWebSocketVersion;
if (versions != null && !versions.Intersect(Consts.SupportedClientVersions).Any())
{
throw new WebSocketException(WebSocketErrorCode.HandshakeVersionNotSupported);
}
throw new WebSocketException(WebSocketErrorCode.HandshakeInvalidStatusCode);
}
var challenge = Encoding.UTF8.GetBytes(handshake.SecWebSocketKey + Consts.ServerGuid);
var hash = Sha1Digest.ComputeHash(challenge);
var calculatedAccept = Convert.ToBase64String(hash);
if (response.SecWebSocketAccept != calculatedAccept)
{
throw new WebSocketException(WebSocketErrorCode.HandshakeInvalidSecWebSocketAccept);
}
response.RequestMessage = handshake;
Interlocked.Exchange(ref _state, WebSocketState.Open);
return(response);
}
public static WebSocketResponseHandshake Parse(IList <string> responseLines)
{
if (responseLines == null || responseLines.Count < 1)
{
throw new ArgumentException(ErrorMessages.NoHeaderLines, "responseLines");
}
var responseLine = responseLines[0].Split(' ');
if (responseLine.Length < 3)
{
throw new ArgumentException(ErrorMessages.InvalidResponseLine + responseLines[0], "responseLines");
}
var response = new WebSocketResponseHandshake
{
StatusCode = (HttpStatusCode)Convert.ToInt32(responseLine[1]),
ReasonPhrase = string.Join(" ", responseLine.Skip(2)),
Version = new Version(responseLine[0].Substring(5)), // "HTTP/x.x"
};
foreach (var line in responseLines.Skip(1))
{
if (string.IsNullOrEmpty(line))
{
break;
}
var pos = line.IndexOf(':');
if (pos < 0)
{
continue;
}
var key = line.Substring(0, pos).Trim().ToLowerInvariant();
var value = line.Substring(pos + 1).Trim();
var values = value.Split(',').Select(v => v.Trim()).Where(v => v.Length > 0);
if (key == "date")
{
response.Headers.Add(key, value);
}
else if (key.StartsWith("content-") || key == "expires" || key == "last-modified")
{
if (response.Content == null)
{
response.Content = new CustomHttpContent();
}
if (key == "expires")
{
int offset;
if (int.TryParse(value, out offset)) // "0" or "-1"
{
response.Content.Headers.Add(key, DateTime.UtcNow.AddSeconds(offset).ToString("R"));
}
else
{
response.Content.Headers.Add(key, value);
}
}
else
{
response.Content.Headers.Add(key, values);
}
}
else
{
try
{
response.Headers.Add(key, values);
}
catch
{
try
{
response.Headers.Add(key, value);
}
catch (Exception ex)
{
response.LogWarning("Failed to add header '{0}': {1}", key, ex);
}
}
}
}
return(response);
}
