ssl - Kestel (.NET Core 3.1) 是否支持 md5RSA 证书？

Question

我一直在尝试运行一个简单的 HTTPS 安全 Kestrel 服务，该服务使用已安装的自签名根证书(来自第 3 方)验证客户端。我正在努力寻找客户端证书的具体问题以及服务反弹连接的原因。有人可以明确回答 .NET Core 3.1 中的 Kestrel 在运行 OpenSSL 1.0.2k-fips 2017 年 1 月 26 日的 Linux 机器上不再接受具有 md5RSA 签名算法的根证书吗？

我一直无法找到任何方法从 Kestrel 中找到更具体的内容。
我在 program.cs 中添加了以下内容以提供帮助:

    private static bool ClientCertificateValidation(X509Certificate2 clientCertificate, X509Chain chain, SslPolicyErrors sslPolicyErrors)
        {
            StringBuilder sb = new StringBuilder();
            int certNumber = 0;
            foreach (X509ChainElement element in chain.ChainElements)
            {
                certNumber++;
                var errors = element.ChainElementStatus;
                List<string> errorList = new List<string>();
                foreach(var cError in errors)
                {
                    errorList.Add(cError.StatusInformation);
                }
                sb.AppendLine("Certificate #" + certNumber + ": (" + string.Join(",", errorList.ToArray())  + ")");
                sb.AppendLine("  Subject: " + element.Certificate.Subject);
                sb.AppendLine("  Issuer: " + element.Certificate.Issuer);
                sb.AppendLine("  Serial #: " + element.Certificate.SerialNumber);
                sb.AppendLine("  Thumbprint: " + element.Certificate.Thumbprint);
                sb.AppendLine("  Valid Dates: " + element.Certificate.NotBefore.ToString() + " to " + element.Certificate.NotAfter.ToString());
                sb.AppendLine("  Signature Algorithm: " + element.Certificate.SignatureAlgorithm.FriendlyName);
                sb.AppendLine("  Version: " + element.Certificate.Version);
                sb.AppendLine("  Encoded Certificate: " + Convert.ToBase64String(element.Certificate.Export(X509ContentType.Cert)));
            }

            Console.WriteLine(sb.ToString());

                if (sslPolicyErrors.HasFlag(SslPolicyErrors.None))
            {
                Console.WriteLine($"***************** NO POLICY ERRORS! **********************");
                return true;
            }
            return false;    
        }

通过以下方式调用它:

 public static IHostBuilder CreateHostBuilder(string[] args) =>
            Host.CreateDefaultBuilder(args)
            .UseSerilog()
            .ConfigureWebHostDefaults(webBuilder =>
            {
                webBuilder.UseStartup<Startup>();
                webBuilder.ConfigureKestrel(options =>
                {
                    options.ConfigureHttpsDefaults(
                        httpsOptions =>
                        {
                            httpsOptions.ClientCertificateMode = ClientCertificateMode.RequireCertificate;
                            httpsOptions.SslProtocols = SslProtocols.Tls12;
                            httpsOptions.ClientCertificateValidation =ClientCertificateValidation;
                        });
                });
            });

但真正的“证书签名失败”让我没什么可继续的。运行 openssl verify - 结果还可以……那么 Kestrel 在做什么？
提前致谢
更新:
自签名(第 3 方)证书安装在服务器上以验证第 3 方的客户端。提到的命令确实返回错误，但由于证书是由第 3 方提供的，我不确定它有什么问题？

Answer 1

好的，所以 dotnet 和 openssl 都同意签名无效。尽管我看不到重现此问题的实用方法，但“未知摘要”(而不是“错误填充”或“超出范围”)表明签名实际上是由发行人创建的(即没有损坏的数据或签名，或者错误的 key )但签名者做错了。尝试以下过程(我使用了自己的证书，因为您的证书太私密，任何人都看不到):

$ openssl req -newkey rsa:1024 -keyout 70348834.key -nodes -x509 -md5 -subj /CN=70348834 -out 70348834.crt
Generating a RSA private key
.....+++++
....+++++
writing new private key to '70348834.key'
-----
# RSA-1024 no longer meets standards but this is just for testing
$ openssl verify -check_ss_sig -CAfile 70348834.crt 70348834.crt
70348834.crt: OK
$ openssl asn1parse -i <70348834.crt
    0:d=0  hl=4 l= 514 cons: SEQUENCE
    4:d=1  hl=4 l= 363 cons:  SEQUENCE
    8:d=2  hl=2 l=   3 cons:   cont [ 0 ]
   10:d=3  hl=2 l=   1 prim:    INTEGER           :02
   13:d=2  hl=2 l=  20 prim:   INTEGER           :39163AA0A0B6898D0DF0304F4F8D5649507B4877
   35:d=2  hl=2 l=  13 cons:   SEQUENCE
   37:d=3  hl=2 l=   9 prim:    OBJECT            :md5WithRSAEncryption
   48:d=3  hl=2 l=   0 prim:    NULL
   50:d=2  hl=2 l=  19 cons:   SEQUENCE
   52:d=3  hl=2 l=  17 cons:    SET
   54:d=4  hl=2 l=  15 cons:     SEQUENCE
   56:d=5  hl=2 l=   3 prim:      OBJECT            :commonName
   61:d=5  hl=2 l=   8 prim:      UTF8STRING        :70348834
   71:d=2  hl=2 l=  30 cons:   SEQUENCE
   73:d=3  hl=2 l=  13 prim:    UTCTIME           :211217042113Z
   88:d=3  hl=2 l=  13 prim:    UTCTIME           :220116042113Z
  103:d=2  hl=2 l=  19 cons:   SEQUENCE
  105:d=3  hl=2 l=  17 cons:    SET
  107:d=4  hl=2 l=  15 cons:     SEQUENCE
  109:d=5  hl=2 l=   3 prim:      OBJECT            :commonName
  114:d=5  hl=2 l=   8 prim:      UTF8STRING        :70348834
  124:d=2  hl=3 l= 159 cons:   SEQUENCE
  127:d=3  hl=2 l=  13 cons:    SEQUENCE
  129:d=4  hl=2 l=   9 prim:     OBJECT            :rsaEncryption
  140:d=4  hl=2 l=   0 prim:     NULL
  142:d=3  hl=3 l= 141 prim:    BIT STRING
  286:d=2  hl=2 l=  83 cons:   cont [ 3 ]
  288:d=3  hl=2 l=  81 cons:    SEQUENCE
  290:d=4  hl=2 l=  29 cons:     SEQUENCE
  292:d=5  hl=2 l=   3 prim:      OBJECT            :X509v3 Subject Key Identifier
  297:d=5  hl=2 l=  22 prim:      OCTET STRING      [HEX DUMP]:041438C135B9D18DF0668B0AA31933FE0F947FBEDF84
  321:d=4  hl=2 l=  31 cons:     SEQUENCE
  323:d=5  hl=2 l=   3 prim:      OBJECT            :X509v3 Authority Key Identifier
  328:d=5  hl=2 l=  24 prim:      OCTET STRING      [HEX DUMP]:3016801438C135B9D18DF0668B0AA31933FE0F947FBEDF84
  354:d=4  hl=2 l=  15 cons:     SEQUENCE
  356:d=5  hl=2 l=   3 prim:      OBJECT            :X509v3 Basic Constraints
  361:d=5  hl=2 l=   1 prim:      BOOLEAN           :255
  364:d=5  hl=2 l=   5 prim:      OCTET STRING      [HEX DUMP]:30030101FF
  371:d=1  hl=2 l=  13 cons:  SEQUENCE
  373:d=2  hl=2 l=   9 prim:   OBJECT            :md5WithRSAEncryption
  384:d=2  hl=2 l=   0 prim:   NULL
  386:d=1  hl=3 l= 129 prim:  BIT STRING
# the number before the colon on the last line is the offset of the raw signature
$ openssl asn1parse <70348834.crt -strparse 386 -out 70348834.sig
Error in encoding
139775850254976:error:0D07207B:asn1 encoding routines:ASN1_get_object:header too long:../crypto/asn1/asn1_lib.c:101:
# ignore that error; RSA signature isn't ASN.1, but -strparse still extracts it, see:
$ ls -l 70348834.sig
-rwxrwxrwx 1 dthomps dthomps 128 Dec 16 23:27 70348834.sig
$ openssl rsautl -verify -certin -inkey 70348834.crt -in 70348834.sig -asn1parse
    0:d=0  hl=2 l=  32 cons: SEQUENCE
    2:d=1  hl=2 l=  12 cons:  SEQUENCE
    4:d=2  hl=2 l=   8 prim:   OBJECT            :md5
   14:d=2  hl=2 l=   0 prim:   NULL
   16:d=1  hl=2 l=  16 prim:  OCTET STRING
      0000 - 2b 7c cf 6d c8 0f 53 82-0b 57 64 4d 5a e0 d6 9a   +|.m..S..WdMZ...
# FYI rsautl -verify isn't properly a verify operation in cryptographic terms,
# technically it's only the 'recover' part of verify-with-recovery (only for RSA)

您的“恢复”签名应该看起来像我上面的最后一个 block ，除了 OCTET STRING 中的数据(但它应该仍然是相同的长度，l=16)；如果不向证书颁发者或提供者提示他们给你的证书无效。