Updated the request header sent to the OIDC endpoint in so it doesn't…

… result in a redirect response when an invalid system access token is provided. (#6019)

* Updated the request header sent to the OIDC endpoint in  so it doesn't result in a redirect response when an invalid system access token is provided.

* Add comment on what X-TFS-FedAuthRedirect does.

sdk/identity/azure-identity/CHANGELOG.md

@@ -8,6 +8,8 @@
 
 ### Bugs Fixed
 
+- Fixed the request sent in `AzurePipelinesCredential` so it doesn't result in a redirect response when an invalid system access token is provided.
+
 ### Other Changes
 
 - Allow certain response headers to be logged in `AzurePipelinesCredential` for diagnostics and include them in the exception message.

sdk/identity/azure-identity/TROUBLESHOOTING.md

@@ -40,7 +40,7 @@ az account get-access-token --output json --resource https://management.core.win
 |---|---|---|
 | AADSTS900023: Specified tenant identifier `<some tenant ID>` is neither a valid DNS name, nor a valid external domain.|The `tenantId` argument to the `AzurePipelinesCredential` constructor is incorrect| Verify the tenant ID. It must identify the tenant of the user-assigned managed identity or service principal configured for the service connection.|
 | No service connection found with identifier `<GUID>` |The `serviceConnectionId` argument to the `AzurePipelinesCredential` constructor is incorrect| Verify the service connection ID. This parameter refers to the `resourceId` of the Azure Service Connection. It can also be found in the query string of the service connection's configuration in Azure DevOps. [Azure Pipelines documentation](https://learn.microsoft.com/azure/devops/pipelines/library/service-endpoints?view=azure-devops&tabs=yaml) has more information about service connections.|
-|302 (Found) response from OIDC endpoint|The `systemAccessToken` argument to the `AzurePipelinesCredential` constructor is incorrect|Check pipeline configuration. This value comes from the predefined variable `System.AccessToken` [as described in Azure Pipelines documentation](https://learn.microsoft.com/azure/devops/pipelines/build/variables?view=azure-devops&tabs=yaml#systemaccesstoken).|
+|401 (Unauthorized) response from OIDC endpoint|The `systemAccessToken` argument to the `AzurePipelinesCredential` constructor is incorrect|Check pipeline configuration. This value comes from the predefined variable `System.AccessToken` [as described in Azure Pipelines documentation](https://learn.microsoft.com/azure/devops/pipelines/build/variables?view=azure-devops&tabs=yaml#systemaccesstoken).|
 |No value for environment variable `SYSTEM_OIDCREQUESTURI` needed by AzurePipelinesCredential. This should be set by Azure Pipelines. AuthenticationException: AzurePipelinesCredential authentication unavailable.|This code is not running inside of the Azure Pipelines environment. You may be running this code locally or on some other environment.|This credential is only designed to run inside the Azure Pipelines environment for the federated identity to work.|
 |AADSTS700016: Application with identifier 'clientId' was not found in the directory 'Microsoft'. 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.|The `<clientId>` provided is invalid|Verify the client ID argument is valid. If the service connection's federated identity was registered via a user-assigned managed identity, the client ID of the managed identity should be provided. If the service connection's federated identity is registered via an app registration, the Application (client) ID from your app registration should be provided.|
 

sdk/identity/azure-identity/src/azure_pipelines_credential.cpp

@@ -115,6 +115,9 @@ Request AzurePipelinesCredential::CreateOidcRequestMessage() const
   request.SetHeader("content-type", "application/json");
   request.SetHeader("authorization", "Bearer " + m_systemAccessToken);
 
+  // Prevents the service from responding with a redirect HTTP status code (useful for automation).
+  request.SetHeader("X-TFS-FedAuthRedirect", "Suppress");
+
   return request;
 }
 

sdk/identity/azure-identity/test/ut/azure_pipelines_credential_test.cpp

@@ -748,7 +748,7 @@ TEST(AzurePipelinesCredential, InvalidServiceConnectionId_LIVEONLY_)
   }
 }
 
-TEST(AzurePipelinesCredential, DISABLED_InvalidSystemAccessToken_LIVEONLY_)
+TEST(AzurePipelinesCredential, InvalidSystemAccessToken_LIVEONLY_)
 {
   std::string tenantId = Environment::GetVariable("AZURESUBSCRIPTION_TENANT_ID");
   std::string clientId = Environment::GetVariable("AZURESUBSCRIPTION_CLIENT_ID");
@@ -777,6 +777,7 @@ TEST(AzurePipelinesCredential, DISABLED_InvalidSystemAccessToken_LIVEONLY_)
   }
   catch (AuthenticationException const& ex)
   {
-    EXPECT_TRUE(std::string(ex.what()).find("302 (Found)") != std::string::npos) << ex.what();
+    EXPECT_TRUE(std::string(ex.what()).find("401 (Unauthorized)") != std::string::npos)
+        << ex.what();
   }
 }