.net - 错误 : Could not create SSL/TLS secure channel Windows 8

Question

升级到 Windows 8 后，我在使用以前工作的 Web 服务调用时遇到问题。我已经在两台 Windows 8.1 机器和一台 Windows 8 机器上验证了以下代码失败，但它在 Windows 7 和 Windows Server 2008 R2 上运行没有错误。

var uriString = "https://secure.unitedmileageplus.com/";

HttpWebRequest request = (HttpWebRequest)WebRequest.Create(uriString);

try {
    using(WebResponse response = request.GetResponse()) {
        response.Dump();
    }
}
catch(Exception e) {
    e.Dump();
}

WebException The request was aborted: Could not create SSL/TLS secure channel.

它似乎已本地化到此端点，因为我能够成功地对其他 URL 进行 SSL 调用。我已经完成了一些 Wireshark 嗅探，但不知道要寻找什么，这没什么帮助。如果您希望我也提供这些日志，请告诉我。

Answer 1

WebRequest 默认将 TLS/SSL 版本设置为 TLS 1.0。您可以使用 ServicePointManager.SecurityProtocol 将其设置回 SSL 3.0。例如:

static void Main(string[] args)
{
    var uriString = "https://secure.unitedmileageplus.com/";

    HttpWebRequest request = (HttpWebRequest)WebRequest.Create(uriString);

    ServicePointManager.ServerCertificateValidationCallback =
        new RemoteCertificateValidationCallback(AcceptAllCertifications);

    ServicePointManager.SecurityProtocol = SecurityProtocolType.Ssl3;

    try
    {
        using (WebResponse response = request.GetResponse())
        {
            Debug.WriteLine(response);
        }
    }
    catch (Exception e)
    {
        Debug.WriteLine(e);
    }
}

public static bool AcceptAllCertifications(
    object sender,
    System.Security.Cryptography.X509Certificates.X509Certificate certification,
    System.Security.Cryptography.X509Certificates.X509Chain chain,
    SslPolicyErrors sslPolicyErrors)
{
    return true;
}