AzureB2C 身份提供商登录失败：AADB2C99002：用户不存在

Question

我正在尝试 Azure AD B2C，并且我已通过 Azure 门户添加了 Google 和 Microsoft 身份提供商。

当我尝试使用 Microsoft 或 Google IP 登录时，我总是在 OnAuthenticationFailed-Handler 中收到以下错误消息：

AADB2C99002： 用户不存在。请先注册，然后才能登录。

但是，当我使用 Azure B2C 提供的“本地帐户登录”时，一切正常。我的配置中是否缺少某些内容？

以下代码片段显示了我的 OWIN 配置。

   private void ConfigureAuthentication(IAppBuilder app)
    {
        app.SetDefaultSignInAsAuthenticationType(CookieAuthenticationDefaults.AuthenticationType);

        app.UseCookieAuthentication(new CookieAuthenticationOptions());

        OpenIdConnectAuthenticationOptions options = new OpenIdConnectAuthenticationOptions
        {
            // These are standard OpenID Connect parameters, with values pulled from web.config
            ClientId = clientId,
            RedirectUri = redirectUri,
            PostLogoutRedirectUri = redirectUri,
            Notifications = new OpenIdConnectAuthenticationNotifications
            {
                AuthenticationFailed = OnAuthenticationFailed,
                RedirectToIdentityProvider = OnRedirectToIdentityProvider,
                AuthorizationCodeReceived = OnAuthorizationCodeReceived,
                SecurityTokenValidated = context => {
                    return null;
                    }
                },

            Scope = "openid offline_access",

            // The PolicyConfigurationManager takes care of getting the correct Azure AD authentication
            // endpoints from the OpenID Connect metadata endpoint.  It is included in the PolicyAuthHelpers folder.
            ConfigurationManager = new PolicyConfigurationManager(
                String.Format(CultureInfo.InvariantCulture, aadInstance, tenant, "/v2.0", OIDCMetadataSuffix),
                new string[] { SignUpPolicyId, SignInPolicyId, ProfilePolicyId }),

            // This piece is optional - it is used for displaying the user's name in the navigation bar.
            TokenValidationParameters = new System.IdentityModel.Tokens.TokenValidationParameters
            {
                NameClaimType = "name",
            },
        };

        app.UseOpenIdConnectAuthentication(options);
    }

    // This notification can be used to manipulate the OIDC request before it is sent.  Here we use it to send the correct policy.
    private async Task OnRedirectToIdentityProvider(RedirectToIdentityProviderNotification<OpenIdConnectMessage, OpenIdConnectAuthenticationOptions> notification)
    {
        PolicyConfigurationManager mgr = notification.Options.ConfigurationManager as PolicyConfigurationManager;
        if (notification.ProtocolMessage.RequestType == OpenIdConnectRequestType.LogoutRequest)
        {
            OpenIdConnectConfiguration config = await mgr.GetConfigurationByPolicyAsync(CancellationToken.None, notification.OwinContext.Authentication.AuthenticationResponseRevoke.Properties.Dictionary[AzureB2C.PolicyKey]);
            notification.ProtocolMessage.IssuerAddress = config.EndSessionEndpoint;
        }
        else
        {
            OpenIdConnectConfiguration config = await mgr.GetConfigurationByPolicyAsync(CancellationToken.None, notification.OwinContext.Authentication.AuthenticationResponseChallenge.Properties.Dictionary[AzureB2C.PolicyKey]);
            notification.ProtocolMessage.IssuerAddress = config.AuthorizationEndpoint;
        }
    }

    private async Task OnAuthorizationCodeReceived(AuthorizationCodeReceivedNotification notification)
    {
        // The user's objectId is extracted from the claims provided in the id_token, and used to cache tokens in ADAL
        // The authority is constructed by appending your B2C directory's name to "https://login.microsoftonline.com/"
        // The client credential is where you provide your application secret, and is used to authenticate the application to Azure AD
        string userObjectID = notification.AuthenticationTicket.Identity.FindFirst("http://schemas.microsoft.com/identity/claims/objectidentifier").Value;
        string authority = String.Format(CultureInfo.InvariantCulture, aadInstance, tenant, string.Empty, string.Empty);
        ClientCredential credential = new ClientCredential(clientId, clientSecret);

        // We don't care which policy is used to access the TaskService, so let's use the most recent policy
        string mostRecentPolicy = notification.AuthenticationTicket.Identity.FindFirst(AzureB2C.AcrClaimType).Value;

        // The Authentication Context is ADAL's primary class, which represents your connection to your B2C directory
        // ADAL uses an in-memory token cache by default.  In this case, we've extended the default cache to use a simple per-user session cache
        AuthenticationContext authContext = new AuthenticationContext(authority, new NaiveSessionCache(userObjectID));

        // Here you ask for a token using the web app's clientId as the scope, since the web app and service share the same clientId.
        // The token will be stored in the ADAL token cache, for use in our controllers
        AuthenticationResult result = await authContext.AcquireTokenByAuthorizationCodeAsync(notification.Code, new Uri(redirectUri), credential, new string[] { clientId }, mostRecentPolicy);
    }

    // Used for avoiding yellow-screen-of-death
    private Task OnAuthenticationFailed(AuthenticationFailedNotification<OpenIdConnectMessage, OpenIdConnectAuthenticationOptions> notification)
    {
        _log.Error("AuthenticationFailed!\r\nError={0}\r\nErrorDescription={1}\r\n{0}",
            notification.ProtocolMessage.Error,
             notification.ProtocolMessage.ErrorDescription,
            notification.Exception.ToString());

        notification.HandleResponse();
        notification.Response.Redirect("/Home/OpenIdError?message=" + notification.ProtocolMessage.ErrorDescription);
        return Task.FromResult(0);
    }
}

Answer 1

外部身份在登录之前首先需要“注册”。在注册期间，外部身份会链接到B2C。

在注册页面中，您可以询问用户的其他属性，例如客户编号。对于外部身份和Local AccountB2C 中的用户，您都需要此信息，两者之间没有区别。

与在没有 B2C 的情况下添加身份提供商相比，这是不同的行为，在 B2C 中，每次登录都可以正常工作。

编辑：就像康斯坦丁提到的那样，新的组合sign-up or sign-in policy解决了这个问题： https://azure.microsoft.com/en-us/documentation/articles/active-directory-b2c-reference-policies/#create-a-sign-up-或登录策略