强制 HttpWebRequest 发送客户端证书

Question

我有一个 p12 证书，我以这种方式加载它：

X509Certificate2 certificate = new X509Certificate2(certName, password,
        X509KeyStorageFlags.MachineKeySet | X509KeyStorageFlags.PersistKeySet |
        X509KeyStorageFlags.Exportable);

它被正确加载，事实上如果我这样做certificate.PrivateKey.ToXmlString(true); 它会返回一个完整的 xml 而没有错误。 但如果我这样做：

try
{
    X509Chain chain = new X509Chain();
    var chainBuilt = chain.Build(certificate);
    Console.WriteLine("Chain building status: "+ chainBuilt);

    if (chainBuilt == false)
        foreach (X509ChainStatus chainStatus in chain.ChainStatus)
            Console.WriteLine("Chain error: "+ chainStatus.Status);
}
catch (Exception ex)
{
    Console.WriteLine(ex);
}

它写道：

Chain building status: False
Chain error: RevocationStatusUnknown 
Chain error: OfflineRevocation 

所以当我这样做时：

        ServicePointManager.CheckCertificateRevocationList = false;
    ServicePointManager.ServerCertificateValidationCallback = (a, b, c, d) => true;
    ServicePointManager.Expect100Continue = true;
    Console.WriteLine("connessione a:" + host);
    HttpWebRequest req = (HttpWebRequest)WebRequest.Create(host);
    req.PreAuthenticate = true;
    req.AllowAutoRedirect = true;
    req.ClientCertificates.Add(certificate);
    req.Method = "POST";
    req.ContentType = "application/x-www-form-urlencoded";
    string postData = "login-form-type=cert";
    byte[] postBytes = Encoding.UTF8.GetBytes(postData);
    req.ContentLength = postBytes.Length;
    Stream postStream = req.GetRequestStream();
    postStream.Write(postBytes, 0, postBytes.Length);
    postStream.Flush();
    postStream.Close();

    WebResponse resp = req.GetResponse();

服务器说证书未发送/无效。

我的问题是：

• 即使链构建错误，我如何发送证书？
• 还有另一个类发布证书，在发送之前不检查证书验证？

非常感谢。 安东尼诺

Answer 1

我解决了问题，关键是P12文件（作为PFX）包含超过1个证书，因此必须以这种方式加载：

X509Certificate2Collection certificates = new X509Certificate2Collection();
certificates.Import(certName, password, X509KeyStorageFlags.MachineKeySet | X509KeyStorageFlags.PersistKeySet);

并以这种方式添加到HttpWebRequest：request.ClientCertificates = certificates;

感谢大家的支持。

完整的示例代码

string host = @"https://localhost/";
string certName = @"C:\temp\cert.pfx";
string password = @"password";

try
{
    X509Certificate2Collection certificates = new X509Certificate2Collection();
    certificates.Import(certName, password, X509KeyStorageFlags.MachineKeySet | X509KeyStorageFlags.PersistKeySet);

    ServicePointManager.ServerCertificateValidationCallback = (a, b, c, d) => true;
    HttpWebRequest req = (HttpWebRequest)WebRequest.Create(host);
    req.AllowAutoRedirect = true;
    req.ClientCertificates = certificates;
    req.Method = "POST";
    req.ContentType = "application/x-www-form-urlencoded";
    string postData = "login-form-type=cert";
    byte[] postBytes = Encoding.UTF8.GetBytes(postData);
    req.ContentLength = postBytes.Length;

    Stream postStream = req.GetRequestStream();
    postStream.Write(postBytes, 0, postBytes.Length);
    postStream.Flush();
    postStream.Close();
    WebResponse resp = req.GetResponse();

    Stream stream = resp.GetResponseStream();
    using (StreamReader reader = new StreamReader(stream))
    {
        string line = reader.ReadLine();
        while (line != null)
        {
            Console.WriteLine(line);
            line = reader.ReadLine();
        }
    }

    stream.Close();
}
catch(Exception e)
{
    Console.WriteLine(e);
}

Answer 2

我使用您的代码的修改版本创建了一个命令行程序，其中包含从 IE 导出的私钥的 pfx 证书，并且我能够对安全网站进行身份验证并检索受保护的页面：

string host = @"https://localhost/";
string certName = @"C:\temp\cert.pfx";
string password = @"password";

try
{
    X509Certificate2 certificate = new X509Certificate2(certName, password);

    ServicePointManager.CheckCertificateRevocationList = false;
    ServicePointManager.ServerCertificateValidationCallback = (a, b, c, d) => true;
    ServicePointManager.Expect100Continue = true;
    HttpWebRequest req = (HttpWebRequest)WebRequest.Create(host);
    req.PreAuthenticate = true;
    req.AllowAutoRedirect = true;
    req.ClientCertificates.Add(certificate);
    req.Method = "POST";
    req.ContentType = "application/x-www-form-urlencoded";
    string postData = "login-form-type=cert";
    byte[] postBytes = Encoding.UTF8.GetBytes(postData);
    req.ContentLength = postBytes.Length;

    Stream postStream = req.GetRequestStream();
    postStream.Write(postBytes, 0, postBytes.Length);
    postStream.Flush();
    postStream.Close();
    WebResponse resp = req.GetResponse();

    Stream stream = resp.GetResponseStream();
    using (StreamReader reader = new StreamReader(stream))
    {
        string line = reader.ReadLine();
        while (line != null)
        {
            Console.WriteLine(line);
            line = reader.ReadLine();
        }
    }

    stream.Close();
}
catch(Exception e)
{
    Console.WriteLine(e);
}

Answer 3

问题是您将私钥安装到机器存储中，通常不允许将私钥用于不在本地系统帐户下运行或具有显式私钥权限的进程的客户端身份验证。您需要在当前用户存储中安装密钥：

X509Certificate2 certificate = new X509Certificate2(certName, password,
        X509KeyStorageFlags.UserKeySet | X509KeyStorageFlags.PersistKeySet |
        X509KeyStorageFlags.Exportable);

Answer 4

我正在尝试使用自签名证书，其唯一目的是“服务器证书”作为客户端证书，使用以下代码：

        HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create("https://serverurl.com/test/certauth");
        X509Store store = new X509Store(StoreName.My, StoreLocation.LocalMachine);
        store.Open(OpenFlags.ReadWrite);
        var certificate = store.Certificates.Find(X509FindType.FindByThumbprint, "a909502dd82ae41433e6f83886b00d4277a32a7b", true)[0];
        request.ClientCertificates.Add(certificate);
        HttpWebResponse response = (HttpWebResponse)request.GetResponse();

我了解到 .NET Framework 将接受这样的证书作为客户端证书，但 .NET Core 不会（请参阅https://github.com/dotnet/runtime/issues/26531）。

有两种解决方案：

1. 切换到 .NET 框架
2. 生成新的自签名证书，其用途/增强密钥用法 = 客户端证书。然后代码也可以在 Core 中运行。