Aplikasi desktop yang memanggil API web: Memperoleh token menggunakan nama pengguna dan kata sandi

Di aplikasi desktop, Anda dapat menggunakan alur nama pengguna dan kata sandi, juga dikenal sebagai Info Masuk Kata Sandi Pemilik Sumber Daya (ROPC), untuk memperoleh token secara diam-diam.

Peringatan

Alur nama pengguna dan kata sandi tidak disarankan karena aplikasi akan meminta kata sandi pengguna secara langsung, yang merupakan pola yang tidak aman. Untuk informasi selengkapnya tentang risiko dan tantangan yang ditimbulkan alur ROPC, lihat "Apa solusi untuk masalah kata sandi yang berkembang?.

Selain itu, dengan menggunakan nama pengguna dan kata sandi, pengembang menyerahkan sejumlah hal, termasuk:

  • Prinsip inti identitas modern - Kata sandi bisa di-phish dan diputar ulang karena rahasia bersama dapat dicegat.
  • Autentikasi multifaktor (MFA) - Pengguna tidak dapat masuk karena tidak ada interaksi.
  • Kemampuan akses menyeluruh (SSO).

Alur nama pengguna dan kata sandi juga memiliki batasan berikut:

  • Alur nama pengguna dan kata sandi tidak kompatibel dengan Akses Bersyar dan autentikasi multifaktor. Jika aplikasi Anda berjalan di penyewa Microsoft Entra tempat admin memerlukan autentikasi multifaktor, seperti yang dilakukan sebagian besar organisasi, Anda tidak dapat menggunakan alur ini.
  • Ini hanya berfungsi untuk akun kerja dan sekolah, bukan Akun Microsoft pribadi.
  • Alur tersedia di desktop .NET dan .NET, tetapi tidak di UWP.

Menggunakan nama pengguna dan kata sandi berguna dalam beberapa kasus, seperti skenario Azure DevOps. Namun, jika Anda ingin menggunakan nama pengguna dan kata sandi dalam skenario interaktif di mana Anda menyediakan UI Anda sendiri, pertimbangkan untuk menjauh darinya.

Alur yang disukai untuk memperoleh token secara diam-diam di Windows adalah menggunakan broker autentikasi Windows. Atau, pengembang juga dapat menggunakan alur Kode perangkat pada perangkat tanpa akses ke browser web.

Jika Anda membangun aplikasi desktop yang memasukkan pengguna dengan identitas sosial menggunakan alur Info Masuk Kata Sandi Pemilik Sumber Daya (ROPC), lihat cara memasukkan pengguna dengan identitas sosial dengan menggunakan Azure AD B2C

Menggunakan alur ROPC

IPublicClientApplicationberisi metode AcquireTokenByUsernamePassword.

Contoh berikut menyajikan kasus yang disederhanakan.

static async Task GetATokenForGraph()
{
 string authority = "https://login.microsoftonline.com/contoso.com";
 string[] scopes = new string[] { "user.read" };
 IPublicClientApplication app;
 app = PublicClientApplicationBuilder.Create(clientId)
       .WithAuthority(authority)
       .Build();
 var accounts = await app.GetAccountsAsync();

 AuthenticationResult result = null;
 if (accounts.Any())
 {
  result = await app.AcquireTokenSilent(scopes, accounts.FirstOrDefault())
                    .ExecuteAsync();
 }
 else
 {
  try
  {
   var securePassword = new SecureString();
   foreach (char c in "dummy")        // you should fetch the password
    securePassword.AppendChar(c);  // keystroke by keystroke

   result = await app.AcquireTokenByUsernamePassword(scopes,
                                                    "joe@contoso.com",
                                                     securePassword)
                      .ExecuteAsync();
  }
  catch(MsalException)
  {
   // See details below
  }
 }
 Console.WriteLine(result.Account.Username);
}

Contoh berikut menyajikan kasus terbaru, dengan penjelasan tentang jenis pengecualian yang bisa Anda dapatkan dan mitigasinya.

static async Task GetATokenForGraph()
{
 string authority = "https://login.microsoftonline.com/contoso.com";
 string[] scopes = new string[] { "user.read" };
 IPublicClientApplication app;
 app = PublicClientApplicationBuilder.Create(clientId)
                                   .WithAuthority(authority)
                                   .Build();
 var accounts = await app.GetAccountsAsync();

 AuthenticationResult result = null;
 if (accounts.Any())
 {
  result = await app.AcquireTokenSilent(scopes, accounts.FirstOrDefault())
                    .ExecuteAsync();
 }
 else
 {
  try
  {
   var securePassword = new SecureString();
   foreach (char c in "dummy")        // you should fetch the password keystroke
    securePassword.AppendChar(c);  // by keystroke

   result = await app.AcquireTokenByUsernamePassword(scopes,
                                                    "joe@contoso.com",
                                                    securePassword)
                    .ExecuteAsync();
  }
  catch (MsalUiRequiredException ex) when (ex.Message.Contains("AADSTS65001"))
  {
   // Here are the kind of error messages you could have, and possible mitigations

   // ------------------------------------------------------------------------
   // MsalUiRequiredException: AADSTS65001: The user or administrator has not consented to use the application
   // with ID '{appId}' named '{appName}'. Send an interactive authorization request for this user and resource.

   // Mitigation: you need to get user consent first. This can be done either statically (through the portal),
   /// or dynamically (but this requires an interaction with Azure AD, which is not possible with
   // the username/password flow)
   // Statically: in the portal by doing the following in the "API permissions" tab of the application registration:
   // 1. Click "Add a permission" and add all the delegated permissions corresponding to the scopes you want (for instance
   // User.Read and User.ReadBasic.All)
   // 2. Click "Grant/revoke admin consent for <tenant>") and click "yes".
   // Dynamically, if you are not using .NET (which does not have any Web UI) by
   // calling (once only) AcquireTokenInteractive.
   // remember that Username/password is for public client applications that is desktop/mobile applications.
   // If you are using .NET or don't want to call AcquireTokenInteractive, you might want to:
   // - use device code flow (See https://aka.ms/msal-net-device-code-flow)
   // - or suggest the user to navigate to a URL to consent: https://login.microsoftonline.com/common/oauth2/v2.0/authorize?client_id={clientId}&response_type=code&scope=user.read
   // ------------------------------------------------------------------------

   // ------------------------------------------------------------------------
   // ErrorCode: invalid_grant
   // SubError: basic_action
   // MsalUiRequiredException: AADSTS50079: The user is required to use multi-factor authentication.
   // The tenant admin for your organization has chosen to oblige users to perform multi-factor authentication.
   // Mitigation: none for this flow
   // Your application cannot use the Username/Password grant.
   // Like in the previous case, you might want to use an interactive flow (AcquireTokenInteractive()),
   // or Device Code Flow instead.
   // Note this is one of the reason why using username/password is not recommended;
   // ------------------------------------------------------------------------

   // ------------------------------------------------------------------------
   // ex.ErrorCode: invalid_grant
   // subError: null
   // Message = "AADSTS70002: Error validating credentials.
   // AADSTS50126: Invalid username or password
   // In the case of a managed user (user from an Azure AD tenant opposed to a
   // federated user, which would be owned
   // in another IdP through ADFS), the user has entered the wrong password
   // Mitigation: ask the user to re-enter the password
   // ------------------------------------------------------------------------

   // ------------------------------------------------------------------------
   // ex.ErrorCode: invalid_grant
   // subError: null
   // MsalServiceException: ADSTS50034: To sign into this application the account must be added to
   // the {domainName} directory.
   // or The user account does not exist in the {domainName} directory. To sign into this application,
   // the account must be added to the directory.
   // The user was not found in the directory
   // Explanation: wrong username
   // Mitigation: ask the user to re-enter the username.
   // ------------------------------------------------------------------------
  }
  catch (MsalServiceException ex) when (ex.ErrorCode == "invalid_request")
  {
   // ------------------------------------------------------------------------
   // AADSTS90010: The grant type is not supported over the /common or /consumers endpoints.
   // Please use the /organizations or tenant-specific endpoint.
   // you used common.
   // Mitigation: as explained in the message from Azure AD, the authority you use in the application needs
   // to be tenanted or otherwise "organizations". change the
   // "Tenant": property in the appsettings.json to be a GUID (tenant Id), or domain name (contoso.com)
   // if such a domain is registered with your tenant
   // or "organizations", if you want this application to sign-in users in any Work and School accounts.
   // ------------------------------------------------------------------------

  }
  catch (MsalServiceException ex) when (ex.ErrorCode == "unauthorized_client")
  {
   // ------------------------------------------------------------------------
   // AADSTS700016: Application with identifier '{clientId}' was not found in the directory '{domain}'.
   // This can happen if the application has not been installed by the administrator of the tenant or consented
   // to by any user in the tenant.
   // You may have sent your authentication request to the wrong tenant
   // Cause: The clientId in the appsettings.json might be wrong
   // Mitigation: check the clientId and the app registration
   // ------------------------------------------------------------------------
  }
  catch (MsalServiceException ex) when (ex.ErrorCode == "invalid_client")
  {
   // ------------------------------------------------------------------------
   // AADSTS70002: The request body must contain the following parameter: 'client_secret or client_assertion'.
   // Explanation: this can happen if your application was not registered as a public client application in Azure AD
   // Mitigation: in the Azure portal, edit the manifest for your application and set the `allowPublicClient` to `true`
   // ------------------------------------------------------------------------
  }
  catch (MsalServiceException)
  {
   throw;
  }

  catch (MsalClientException ex) when (ex.ErrorCode == "unknown_user_type")
  {
   // Message = "Unsupported User Type 'Unknown'. Please see https://aka.ms/msal-net-up"
   // The user is not recognized as a managed user, or a federated user. Azure AD was not
   // able to identify the IdP that needs to process the user
   throw new ArgumentException("U/P: Wrong username", ex);
  }
  catch (MsalClientException ex) when (ex.ErrorCode == "user_realm_discovery_failed")
  {
   // The user is not recognized as a managed user, or a federated user. Azure AD was not
   // able to identify the IdP that needs to process the user. That's for instance the case
   // if you use a phone number
   throw new ArgumentException("U/P: Wrong username", ex);
  }
  catch (MsalClientException ex) when (ex.ErrorCode == "unknown_user")
  {
   // the username was probably empty
   // ex.Message = "Could not identify the user logged into the OS. See https://aka.ms/msal-net-iwa for details."
   throw new ArgumentException("U/P: Wrong username", ex);
  }
  catch (MsalClientException ex) when (ex.ErrorCode == "parsing_wstrust_response_failed")
  {
   // ------------------------------------------------------------------------
   // In the case of a Federated user (that is owned by a federated IdP, as opposed to a managed user owned in an Azure AD tenant)
   // ID3242: The security token could not be authenticated or authorized.
   // The user does not exist or has entered the wrong password
   // ------------------------------------------------------------------------
  }
 }

 Console.WriteLine(result.Account.Username);
}

Untuk informasi selengkapnya tentang semua pengubah yang dapat diterapkan ke AcquireTokenByUsernamePassword, lihat AcquireTokenByUsernamePasswordParameterBuilder.

Langkah berikutnya

Lanjutkan ke artikel berikutnya dalam skenario ini, yaitu Panggil API web dari aplikasi desktop.