无法验证 RS256 签名的 JWT

Question

我正在尝试在 dotnet webapi 上与 KeyCloak 一起实现签名的 JWT (RS256)。在应用启动时，我可以看到对 keycloak 的 openid 调用具有预期的响应内容（请求如下所示）。

在此处获取 jwks_url

GET https://localhost:8080/auth/realms/core/.well-known/openid-configuration

从这里获取密钥

GET https://localhost:8080/auth/realms/core/protocol/openid-connect/certs

然后我得到一个带有以下请求的 access_token

POST https://localhost:8080/auth/realms/core/protocol/openid-connect/token
Content-Type: application/x-www-form-urlencoded

grant_type=password&client_id=admin-cli&username=jim&password=foobar

然后我测试以下端点

[ApiController]
[Route("/")]
public class AppController : ControllerBase
{
    [Authorize]
    [HttpGet]
    public OkObjectResult Get()
    {
        return Ok("This is the secured page");
    }
}

带着这个请求

GET https://localhost:5001
Authorization: Bearer MY_TOKEN 

但我总是收到 401

HTTP/1.1 401 Unauthorized
Content-Length: 0
Date: Wed, 18 Nov 2020 17:41:28 GMT
Server: Kestrel
Www-Authenticate: Bearer error="invalid_token", error_description="The signature key was not found"

签名密钥（第三个“块”）确实存在于令牌中。下面是 JWT 验证代码。我错过了什么吗？

public void ConfigureServices(IServiceCollection services)
{
    services.AddControllers();

    var audience = Configuration["Jwt:Audience"];
    var issuer = Configuration["Jwt:Issuer"];
    bool.TryParse(Configuration["Jwt:RequireHttpsMetadata"], out var requireHttpsMetadata);

    IConfigurationManager<OpenIdConnectConfiguration> configurationManager =
        new ConfigurationManager<OpenIdConnectConfiguration>(
            $"{Configuration["Jwt:Authority"]}/auth/realms/core/.well-known/openid-configuration",
            new OpenIdConnectConfigurationRetriever());
    var openIdConfig =
        configurationManager.GetConfigurationAsync(CancellationToken.None).Result;

    services.AddAuthentication(options =>
        {
            options.DefaultAuthenticateScheme = JwtBearerDefaults.AuthenticationScheme;
            options.DefaultChallengeScheme = JwtBearerDefaults.AuthenticationScheme;
            options.DefaultScheme = JwtBearerDefaults.AuthenticationScheme;
        })
        .AddJwtBearer(options =>
        {
            options.SaveToken = true;
            options.RequireHttpsMetadata = requireHttpsMetadata;
            options.TokenValidationParameters.IssuerSigningKeys = openIdConfig.SigningKeys;
            options.TokenValidationParameters = new TokenValidationParameters
            {
                ValidateIssuer = true,
                ValidateAudience = true,
                ValidateLifetime = true,

                ValidIssuer = issuer,
                ValidAudience = audience,
                ValidateIssuerSigningKey = true,
            };
        });
}

Answer 1

由于 JWT 持有签名（又名第三块），我会解释该消息

"The signature key was not found"

签名验证存在问题。

重新检查响应/可访问性

GET https://localhost:8080/auth/realms/core/protocol/openid-connect/certs