Question

我有一个ASP.NET Core 3.1项目，例如以下示例：Sign-in a user with the Microsoft Identity Platform in a WPF Desktop application and call an ASP.NET Core Web API。

我正在使用Identity web 1.0版和Azure AD单租户应用程序。

由于我只请求一个应用程序令牌，而不是一个用户令牌，所以我编辑了清单，添加了appRoles：

[... more json ...]
"appId": "<guid>",
"appRoles": [
    {
        "allowedMemberTypes": [
            "Application"
        ],
        "description": "Accesses the application.",
        "displayName": "access_as_application",
        "id": "<unique guid>",
        "isEnabled": true,
        "lang": null,
        "origin": "Application",
        "value": "access_as_application"
    }
],
"oauth2AllowUrlPathMatching": false,
[... more json ...]

我还启用了idtyp访问令牌声明，以指定这是一个应用程序令牌。

[... more json ...]
"optionalClaims": {
    "idToken": [],
    "accessToken": [
        {
            "name": "idtyp",
            "source": null,
            "essential": false,
            "additionalProperties": []
        }
    ],
    "saml2Token": []
[... more json ...]

以下请求是由邮递员提出的。请注意/.default与范围的使用，在文档中有关client credentials grant flow提到了作用域。

POST /{tenant_id}/oauth2/v2.0/token HTTP/1.1
Host: login.microsoftonline.com
Content-Type: application/x-www-form-urlencoded

scope=api%3A%2F%2{client_id}%2F.default
&client_id={client_id}
&grant_type=client_credentials
&client_secret={secret_key}

请求返回一个access_token，可以用jwt.ms查看，并且看起来像这样，出于安全原因，实际数据已由占位符替换。：

{
  "typ": "JWT",
  "alg": "RS256",
  "x5t": "[...]",
  "kid": "[...]"
}.{
  "aud": "api://<client_id>",
  "iss": "https://sts.windows.net/<tenant_id>/",
  "iat": 1601803439,
  "nbf": 1601803439,
  "exp": 1601807339,
  "aio": "[...]==",
  "appid": "<app id>",
  "appidacr": "1",
  "idp": "https://sts.windows.net/<tenant_id>/",
  "idtyp": "app",
  "oid": "<guid>",
  "rh": "[..].",
  "roles": [
    "access_as_application"
  ],
  "sub": "<guid>",
  "tid": "<guid>",
  "uti": "[...]",
  "ver": "1.0"
}

我注意到上面的令牌不包含scp。这似乎是正确的，因为这是应用程序令牌而不是用户令牌。相反，它包括“ roles”作为应用程序令牌的适当名称。

access_token现在可以用作Postman Get中的载体：

GET /api/myapi
Host: https://localhost:5001
Authorization: Bearer {access_token}

对此请求的响应为500 internal error。即出了点问题。 access_token看起来像是一个应用程序令牌，因此错误似乎出在ASP.NET Core 3.1控制器端。

ASP.NET Core 3.1。托管自定义API的项目有一个startup.cs，其中包含以下代码：

services.AddMicrosoftIdentityWebApiAuthentication(Configuration);

// This is added for the sole purpose to highlight the origin of the exception.
services.Configure<JwtBearerOptions>(JwtBearerDefaults.AuthenticationScheme, options =>
{
    var existingOnTokenValidatedHandler = options.Events.OnTokenValidated;
    
    options.Events.OnTokenValidated = async context =>
    {
        if (context.Principal.Claims.All(x => x.Type != ClaimConstants.Scope)
            && context.Principal.Claims.All(y => y.Type != ClaimConstants.Scp)
            && context.Principal.Claims.All(y => y.Type != ClaimConstants.Roles))
        {
            // This where the exception originates from:
            throw new UnauthorizedAccessException("Neither scope or roles claim was found in the bearer token.");
        }
    };
});

该项目的appsettings.json包括：

"AzureAD": {
    "Instance": "https://login.microsoftonline.com/",
    "Domain": "mydomain.onmicrosoft.com",
    "ClientId": "<client_id>",
    "TenantId": "<tenant_id>",
    "Audience": "api://<client_id>"
},

...，控制器如下所示：

[Authorize]
[Route("api/[controller]")]
public class MyApiController : Controller
{
    [HttpGet]
    public async Task<string> Get()
    {
        return "Hello world!";
    }
}

500 internal error的根本原因是引发了此异常：IDW10201: Neither scope or roles claim was found in the bearer token.异常。

更新：

（有关更多详细信息，请参见下面的答案）。

有关“ Implementing Authorization in your Applications with Microsoft identity platform - june 2020”的视频建议，丢失的部分是该标志JwtSecurityTokenHandler.DefaultMapInboundClaims = false;，需要在startup.cs中进行设置-例如：

public void ConfigureServices(IServiceCollection services)
{
    // By default, the claims mapping will map clain names in the old format to accommodate older SAML applications.
    //'http://schemas.microsodt.com/ws/2008/06/identity/clains/role' instead of 'roles'
    // This flag ensures that the ClaimsIdentity claims collection will be build from the claims in the token
    JwtSecurityTokenHandler.DefaultMapInboundClaims = false;
    
    [...more code...]

Answer 1

视频“ Implementing Authorization in your Applications with Microsoft identity platform - june 2020”概述缺少的片段是此标志JwtSecurityTokenHandler.DefaultMapInboundClaims = false;，需要在startup.cs中设置-例如：

public void ConfigureServices(IServiceCollection services)
{
    services.AddMicrosoftIdentityWebApiAuthentication(Configuration);

    // By default, the claims mapping will map claim names in the old format to accommodate older SAML applications.
    //'http://schemas.microsodt.com/ws/2008/06/identity/clains/role' instead of 'roles'
    // This flag ensures that the ClaimsIdentity claims collection will be build from the claims in the token
    JwtSecurityTokenHandler.DefaultMapInboundClaims = false;


    // Notice that this part is different in the video, 
    // however in this context the following seems to be 
    // the correct way of setting the RoleClaimType:
    services.Configure<JwtBearerOptions>(JwtBearerDefaults.AuthenticationScheme, options =>
    {
        // The claim in the Jwt token where App roles are available.
        options.TokenValidationParameters.RoleClaimType = "roles";
    });

    [... more code ...]
}

替代1

还可以在startup.cs中为整个应用设置授权：


services.AddControllers(options =>
{
    var policy = new AuthorizationPolicyBuilder()
        .RequireClaim("roles", "access_as_application")
        .Build();
    options.Filters.Add(new AuthorizeFilter(policy));
});

替代2

也可以使用以下策略：

services.AddAuthorization(config =>
{
    config.AddPolicy("Role", policy => 
        policy.RequireClaim("roles", "access_as_application"));
});

现在此策略可用于类似这样的控制器请求：

[HttpGet]
[Authorize(Policy = "Role")]
public async Task<string> Get()
{
    return "Hello world!";
}

文档中的更多内容：Policy based role checks。

Answer 2

只需将DefaultMapInboundClaims添加到您的API服务配置中

public void ConfigureServices(IServiceCollection services)
{
    JwtSecurityTokenHandler.DefaultMapInboundClaims = false;
}

Answer 3

原因是您正在使用默认范围scope=api%3A%2F%2{client_id}%2F.default发出请求，而默认范围inner class WeatherTask(var location: Location) : AsyncTask<String, Void, String>() {在access_token中不包含范围声明，您应该使用已为ASP.NET Core 3.1 API项目注册的特定范围在Azure门户中公开该API。

Answer 4

如果您计划不使用构建作用域或角色，这可能会有所帮助。您可以使用下面针对Azure B2C的示例启用“访问控制列表”身份验证。这是官方文档的一些链接。

https://github.com/AzureAD/microsoft-identity-web/wiki/web-apis#user-content-web-apis-called-by-daemon-apps-using-client-credential-flow

https://docs.microsoft.com/en-us/dotnet/api/microsoft.identity.web.microsoftidentityoptions.allowwebapitobeauthorizedbyacl?view=azure-dotnet-preview

将以下内容添加到您的广告配置中： "AllowWebApiToBeAuthorizedByACL": true

示例：

"AzureAdB2C": {
    "Instance": "https://xxx.b2clogin.com/",
    "ClientId": "xxxx",
    "Domain": "xxx.onmicrosoft.com",
    "SignUpSignInPolicyId": "xxx",
    "AllowWebApiToBeAuthorizedByACL": true
  },

关于ACL /访问控制列表的含义： ACL：https://en.wikipedia.org/wiki/Access-control_list

IDW10201：在承载令牌中未找到范围或角色声明

4 个答案: