Question

我有许多ASP.NET网站和一个使用相同代码“登录”到第三方网站的网络服务。这包括基本上使用WebRequest使用我的凭据对网站的登录页面执行HTTP POST，将结果cookie存储在CookieContainer中，并在任何后续WebRequests中使用该CookieContainer来授权我的网站访问第三方网站上的页面。 / p>

代码基本如下：

    public LoginResults Login()
    {
        // Create the webrequest
        var request = CreateInitialWebRequest(LOGIN_URL);
        request.AllowAutoRedirect = false;

        // Set the cookiecontainer, which will be filled with the authentication cookies
        this.cookieContainer = new CookieContainer();
        request.CookieContainer = this.cookieContainer;

        // Set the username and pw in a HTTP POST call
        SetPostContent(request, string.Format(LOGIN_PARAMETERS, this.Username, this.Password));

        // Read the response
        using (var httpWebResponse = (HttpWebResponse)request.GetResponse())
        {
            using (var responseStream = httpWebResponse.GetResponseStream())
            {
                 // Omitted:
                 // read response and determine if login was successful
            } 
        }
    }

    private HttpWebRequest CreateInitialWebRequest(string uri)
    {
        var request = (HttpWebRequest)WebRequest.Create(uri);
        ServicePointManager.ServerCertificateValidationCallback = delegate { return true; };
        return request;
    }

    private HttpWebRequest CreateWebRequest(string uri)
    {
        var request = this.CreateInitialWebRequest(uri);
        request.CookieContainer = cookieContainer;
        request.Accept = "image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, application/x-ms-application, application/vnd.ms-xpsdocument, application/xaml+xml, application/x-ms-xbap, application/x-shockwave-flash, */*";
        request.UserAgent = "User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0; SLCC1; .NET CLR 2.0.50727; Media Center PC 5.0; .NET CLR 3.0.04506; .NET CLR 3.5.21022)";
        request.Method = "GET";
        request.Timeout = 10000; // 10 sec
        return request;
    }

    private static void SetPostContent(HttpWebRequest req, string postData)
    {
        req.Method = "POST";
        byte[] bytes = new ASCIIEncoding().GetBytes(postData);
        req.ContentType = "application/x-www-form-urlencoded";
        req.ContentLength = (long)bytes.Length;
        ((WebRequest)req).GetRequestStream().Write(bytes, 0, bytes.Length);
        ((WebRequest)req).GetRequestStream().Close();
    }

此代码已经工作了很长时间（几个月，超过半年）。从本周末开始，它已经开始失败（我估计有90％的时间，但不是100％的时间）。我一直看到的错误是： System.Net.WebException：底层连接已关闭：发送时发生意外错误。 ---＆GT; System.IO.IOException：由于意外的数据包格式，握手失败。 堆栈跟踪如下：

System.Net.WebException: The underlying connection was closed: An unexpected error occurred on a send. ---> System.IO.IOException: The handshake failed due to an unexpected packet format.
at System.Net.Security.SslState.StartReadFrame(Byte[] buffer, Int32 readBytes, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.StartReceiveBlob(Byte[] buffer, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.CheckCompletionBeforeNextReceive(ProtocolToken message, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.StartSendBlob(Byte[] incoming, Int32 count, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.ForceAuthentication(Boolean receiveFirst, Byte[] buffer, AsyncProtocolRequest asyncRequest)
at System.Net.Security.SslState.ProcessAuthentication(LazyAsyncResult lazyResult)
at System.Net.TlsStream.CallProcessAuthentication(Object state)
at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Net.TlsStream.ProcessAuthentication(LazyAsyncResult result)
at System.Net.TlsStream.Write(Byte[] buffer, Int32 offset, Int32 size)
at System.Net.PooledStream.Write(Byte[] buffer, Int32 offset, Int32 size)
at System.Net.ConnectStream.WriteHeaders(Boolean async)
--- End of inner exception stack trace ---
at System.Net.HttpWebRequest.GetRequestStream(TransportContext& context)
at System.Net.HttpWebRequest.GetRequestStream()
at iRacingForumService.HttpPost.SetPostContent(HttpWebRequest req, String postData)
at iRacingForumService.HttpPost.Login()

当我谷歌这个错误时，我一直看到的唯一解决方案是禁用WebRequest的KeepAlive属性和/或将ProtocolVersion设置为HttpVersion10。我尝试过（两种可能的组合）并没有任何帮助。

错误并不总是出现，但是当它出现时我可以继续尝试我喜欢的一切，我会一次又一次地一次又一次地得到错误。如果我离开它几分钟然后再试一次，我有可能它会起作用（一旦它发生，它会继续工作一段时间）。

奇怪的是，我没有改变任何东西;这段代码已运行数月没有问题。完全有可能第三方网站改变了一些东西，和/或我的网站托管服务提供商改变了一些东西。但是，万一我可以采取措施来解决这个问题，我想问一下我做错了什么。

我可以联系第三方网站（可能不会得到回复）或我的网站主办，但我需要更好地了解到底出了什么问题，因为只是向他们抛出这个错误可能无法帮助他们。 / p>

那么，有什么我可以做的，或者有充分的理由让我突然在我的所有网站上看到这个错误（他们都连接到同一个第三方网站）？

由于

Answer 1

由于间歇性地发生这种情况，您可能需要联系服务器管理员并了解最新情况。由于负载，配置错误或其他一些网络问题，服务器可能会拒绝或关闭连接。

由于意外的数据包格式，WebRequest握手失败

1 个答案: