Question

我有一个JWT，它是由我的AWS ALB使用OpenID连接器创建的。我需要在我的C＃应用程序中验证令牌。但是我很难使其正常工作。

AWS在此描述令牌验证：https://docs.aws.amazon.com/elasticloadbalancing/latest/application/listener-authenticate-users.html?icmpid=docs_elbv2_console

它应该分三步工作：

从令牌中获取密钥ID
从a (https://public-keys.auth.elb.' + region + '.amazonaws.com/' + key id)的aws中读取公共密钥
使用密钥解密有效载荷

这是我得到的JWT：

eyJ0eXAiOiJKV1QiLCJraWQiOiJjODE4ZTcxNi01OTAxLTQzOWQtOWFlZC1lYmRmODAyYjZkYTkiLCJhbGciOiJFUzI1NiIsImlzcyI6Imh0dHBzOi8vc2llbWVucy1xYS0wMDA2OS5ldS5hdXRoMC5jb20vIiwiY2xpZW50IjoiMndsS3k0YlRXbGpZWm9KYXZRSVFqVTE3OUprVG4zNDAiLCJzaWduZXIiOiJhcm46YXdzOmVsYXN0aWNsb2FkYmFsYW5jaW5nOmV1LWNlbnRyYWwtMTo0ODU2ODM0ODcxOTY6bG9hZGJhbGFuY2VyL2FwcC9maW5kLXRlc3QtYWxiLzU3YzBmMWYzZjg0YzZjMjEiLCJleHAiOjE1NzU1NDMwMzN9.eyJzdWIiOiJvYXV0aDJ8bWFpbi10ZW5hbnQtb2lkY3xzYW1scHxTaWVtZW5zfFowMDJFSk5VIiwiZ2l2ZW5fbmFtZSI6IlJhcGhhZWwiLCJmYW1pbHlfbmFtZSI6IlNjaG5haXRsIiwibmlja25hbWUiOiJSYXBoYWVsIiwibmFtZSI6IlJhcGhhZWwgU2NobmFpdGwiLCJwaWN0dXJlIjoiaHR0cHM6Ly9zLmdyYXZhdGFyLmNvbS9hdmF0YXIvODkzNWVlY2QzMDc2ZTAyMTQ5ODE2MTZmZjBkZTRkZjI_cz00ODAmcj1wZyZkPWh0dHBzJTNBJTJGJTJGY2RuLmF1dGgwLmNvbSUyRmF2YXRhcnMlMkZyYS5wbmciLCJ1cGRhdGVkX2F0IjoiMjAxOS0xMi0wNVQxMDo0ODozMy4wNjhaIiwiZXhwIjoxNTc1NTQzMDMzLCJpc3MiOiJodHRwczovL3NpZW1lbnMtcWEtMDAwNjkuZXUuYXV0aDAuY29tLyJ9.M39aPefXmaDGzaDd0qHcQHMhvugTVN4i4pyvGJ-7fayewU9vZdtKvSzFF9rVal8GEz7HKTr_auqMw9HemOW yag ==

因此，密钥ID为：c818e716-5901-439d-9aed-ebdf802b6da9

公钥：

-----BEGIN PUBLIC KEY-----
MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAENARdEGaEpfgHph3440UodVsQdqxi
PYz+l1aEcz+Bivr6emXDnor1nET94dbPqYxk+vtUHGkgOb44VPEZUe4ijQ==
-----END PUBLIC KEY-----

我尝试使用以下方法来验证代码：

使用System.IdentityModel.Tokens.Jwt命名空间。但是我无法将公共密钥作为字符串提供给ValidationParameters。我对这个答案https://stackoverflow.com/a/51866939/2250672采用了类似的方法。感觉很复杂并且容易出错。由于整天无法正常工作，我决定继续使用其中一个提供相同功能的nuget软件包。
使用JWT nuget程序包，但不支持AWS ALB使用的算法。
通过以下代码使用Jose.JWT nuget软件包：

Jose.JWT.Decode(__token, publicKeyPem, Jose.JwsAlgorithm.ES256)

出现以下错误：

错误：脚本执行失败。 [ArgumentException] EcdsaUsingSha算法期望密钥为CngKey或ECDsa类型。

如何简单地在C＃中从AWS ALB验证JWT？

Answer 1

公用密钥在https://siemens-qa-00069.eu.auth0.com/.well-known/openid-configuration上不可用。因此，您可以尝试使用手动方法：

    private static ECDsa LoadPublicKey(byte[] key)
    {
        byte[] pubKeyX = key.Skip(27).Take(32).ToArray();
        byte[] pubKeyY = key.Skip(59).Take(32).ToArray();
        return ECDsa.Create(new ECParameters
        {
            Curve = ECCurve.NamedCurves.nistP256,
            Q = new ECPoint
            {
                X = pubKeyX,
                Y = pubKeyY
            }
        });
    }

        string key = "MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAENARdEGaEpfgHph3440UodVsQdqxiPYz+l1aEcz+Bivr6emXDnor1nET94dbPqYxk+vtUHGkgOb44VPEZUe4ijQ==";
        ECDsa ecdsa = LoadPublicKey(Convert.FromBase64String(key));
        string authorizationDomain = "https://siemens-qa-00069.eu.auth0.com/";
        string jwt = "eyJ0eXAiOiJKV1QiLCJraWQiOiJjODE4ZTcxNi01OTAxLTQzOWQtOWFlZC1lYmRmODAyYjZkYTkiLCJhbGciOiJFUzI1NiIsImlzcyI6Imh0dHBzOi8vc2llbWVucy1xYS0wMDA2OS5ldS5hdXRoMC5jb20vIiwiY2xpZW50IjoiMndsS3k0YlRXbGpZWm9KYXZRSVFqVTE3OUprVG4zNDAiLCJzaWduZXIiOiJhcm46YXdzOmVsYXN0aWNsb2FkYmFsYW5jaW5nOmV1LWNlbnRyYWwtMTo0ODU2ODM0ODcxOTY6bG9hZGJhbGFuY2VyL2FwcC9maW5kLXRlc3QtYWxiLzU3YzBmMWYzZjg0YzZjMjEiLCJleHAiOjE1NzU1NDMwMzN9.eyJzdWIiOiJvYXV0aDJ8bWFpbi10ZW5hbnQtb2lkY3xzYW1scHxTaWVtZW5zfFowMDJFSk5VIiwiZ2l2ZW5fbmFtZSI6IlJhcGhhZWwiLCJmYW1pbHlfbmFtZSI6IlNjaG5haXRsIiwibmlja25hbWUiOiJSYXBoYWVsIiwibmFtZSI6IlJhcGhhZWwgU2NobmFpdGwiLCJwaWN0dXJlIjoiaHR0cHM6Ly9zLmdyYXZhdGFyLmNvbS9hdmF0YXIvODkzNWVlY2QzMDc2ZTAyMTQ5ODE2MTZmZjBkZTRkZjI_cz00ODAmcj1wZyZkPWh0dHBzJTNBJTJGJTJGY2RuLmF1dGgwLmNvbSUyRmF2YXRhcnMlMkZyYS5wbmciLCJ1cGRhdGVkX2F0IjoiMjAxOS0xMi0wNVQxMDo0ODozMy4wNjhaIiwiZXhwIjoxNTc1NTQzMDMzLCJpc3MiOiJodHRwczovL3NpZW1lbnMtcWEtMDAwNjkuZXUuYXV0aDAuY29tLyJ9.M39aPefXmaDGzaDd0qHcQHMhvugTVN4i4pyvGJ-7fayewU9vZdtKvSzFF9rVal8GEz7HKTr_auqMw9HemOWyag==";
        TokenValidationParameters tokenValidationParameters = new TokenValidationParameters
        {
            ValidIssuer = authorizationDomain,
            ValidateAudience = false,
            IssuerSigningKey = new ECDsaSecurityKey(ecdsa)
        };
        try
        {
            JwtSecurityTokenHandler jwtSecurityTokenHandler = new JwtSecurityTokenHandler();
            jwtSecurityTokenHandler.ValidateToken(jwt, tokenValidationParameters, out _);
            return true;
        }
        catch (SecurityTokenException)
        {
            return false;
        }

问题是我无法对其进行测试，因为在我的计算机（Windows 10 + .NET Core 2.1）上，我收到此错误：

System.PlatformNotSupportedException：指定的曲线“ nistP256”或其参数对该平台无效。 ---> Internal.Cryptography.CryptoThrowHelper + WindowsCryptographicException：参数不正确

在C＃中使用--- PUBLIC KEY ---验证JWT（ES256）令牌

1 个答案: