相关疑难解决方法(0)

我正在尝试编写C#代码,该代码针对用于计算Web应用程序中的销售税的REST服务端点发出Web请求.这是第三方服务,使用SSL进行保护.有两种环境,UAT和生产.运行webrequest的代码如下所示:

...

var req = WebRequest.Create(url) as HttpWebRequest;
req.Method = "POST";
req.ContentType = "application/json";

...

using (var webresponse = req.GetResponse())
{
    using (var responseStream = new StreamReader(webresponse.GetResponseStream()))
    {
        var respJson = responseStream.ReadToEnd();
        calcResult = BuildResponse(calcRequest, respJson, consoleWriteRawReqResponse);
    }
}

return calcResult;

这对UAT环境很好.但是当我在生产环境中运行相同的代码时,我收到错误:

"无法创建SSL/TLS安全通道"

我很能没有问题,从邮差执行这两个请求,没有任何特殊的修改.

这导致我走上了调查这个错误的道路,我找到了很多有用的SO帖子来讨论这个话题,包括:

请求已中止:无法创建SSL/TLS安全通道

尽管设置了ServerCertificateValidationCallback,但无法创建SSL/TLS安全通道

这些帮助指向了我正确的方向,即查看将ServicePointManager.SecurityProtocol设置设置为不同的值,并使用ServicePointManager.ServerCertificateValidationCallback来调查错误.

我玩这些后发现的是以下内容:

• UAT环境调用将使用Ssl3 |的默认设置 Tls(.NET 4.5.2的默认值),而生产环境则不会.
• 只有当我将此设置显式设置为Ssl3时,生产调用才会起作用.

该代码如下所示:

...

var req = WebRequest.Create(url) as HttpWebRequest;
req.Method = "POST";
req.ContentType = "application/json";

...

ServicePointManager.SecurityProtocol = SecurityProtocolType.Ssl3;
ServicePointManager.ServerCertificateValidationCallback …

My question is simple, I have read these two main pages :

• The request was aborted: Could not create SSL/TLS secure channel
• MSDN - Element

But from the first link, it's showing configuration for SecurityProtocol set in global.asax.cs for solving

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

Here, I want this config is set in web.config / app.config, just for making it a little specific for own project not for all asp.net projects... Then I …

希望有人可以帮助解决这个问题.最近我们的机器更新了KB4344167,其中包括.NET 4.7.1的安全更新. 不幸的是,这个更新破坏了我们的代码Webrequest.当我们运行下面的代码时,我们收到此错误:

请求已中止:无法创建SSL/TLS安全通道.

// Create a request for the URL.        
WebRequest request = WebRequest.Create(url);
//specify to use TLS 1.2 as default connection
ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12 | SecurityProtocolType.Tls11 | SecurityProtocolType.Tls;
request.Timeout = int.Parse(configmanager.GetSetting("Webtimeout"));
// Set proxy
request.Proxy = WebRequest.DefaultWebProxy;
request.Proxy.Credentials = CredentialCache.DefaultCredentials;
// Define a cache policy for this request only. 
HttpRequestCachePolicy noCachePolicy = new HttpRequestCachePolicy(HttpRequestCacheLevel.NoCacheNoStore);
request.CachePolicy = noCachePolicy;
ServicePointManager.ServerCertificateValidationCallback = (s, cert, chain, ssl) => true;
// Get the response.
HttpWebResponse response …

在过去的 5 年里，我一直在使用 Azure IoT 远程监控解决方案并使用 Azure AD 身份验证来保护应用程序和 API，从上周六开始，我在登录时收到以下错误（黄色屏幕）：

IDX10803：无法创建从“https://login.microsoftonline.com/{Tenant-ID}/.well-known/openid-configuration”获取配置。

这是我的身份验证相关的启动代码：

public void ConfigureAuth(IAppBuilder app, IConfigurationProvider configProvider)
    {
        string aadClientId = configProvider.GetConfigurationSettingValue("ida.AADClientId");
        string aadInstance = configProvider.GetConfigurationSettingValue("ida.AADInstance");
        string aadTenant = configProvider.GetConfigurationSettingValue("ida.AADTenant");
        string authority = string.Format(CultureInfo.InvariantCulture, aadInstance, aadTenant);

        app.SetDefaultSignInAsAuthenticationType(CookieAuthenticationDefaults.AuthenticationType);

        app.UseCookieAuthentication(new CookieAuthenticationOptions());


        app.UseWindowsAzureActiveDirectoryBearerAuthentication(
            new WindowsAzureActiveDirectoryBearerAuthenticationOptions
            {
                Tenant = ConfigurationManager.AppSettings["ida:Tenant"],
                TokenValidationParameters = new TokenValidationParameters { SaveSigninToken = true, ValidAudience = ConfigurationManager.AppSettings["ida:Audience"] }
            });


        app.UseOpenIdConnectAuthentication(
            new OpenIdConnectAuthenticationOptions
            {
                ClientId = aadClientId,
                Authority = authority,
                TokenValidationParameters = new TokenValidationParameters()
                {
                    ValidateIssuer = false
                },
                Notifications …

我无法绕过生产服务器中的证书验证，因为ServicePointManager.ServerCertificateValidationCallback从未调用过：

ServicePointManager.ServerCertificateValidationCallback = ValidateRemoteCertificate;

...

private bool ValidateRemoteCertificate(
    object sender, X509Certificate cert, X509Chain chain, SslPolicyErrors policyErrors)
{
    LogActionToTable(EntrySeverity.Information, 
        $"ValidateRemoteCertificate() Certificate name: {cert.Subject}");
    return true;
}

当从 Web 应用程序中的方法调用时，该行永远不会执行，奇怪的是它是从单元测试 (NUnit) 中正确调用的。

ServicePointManager
  .ServerCertificateValidationCallback += 
    (sender, cert, chain, sslPolicyErrors) => true;