| // Copyright 2024 Google LLC |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| // Package externalaccount provides support for creating workload identity |
| // federation and workforce identity federation token providers that can be used |
| // to access Google Cloud resources from external identity providers. |
| // |
| // # Workload Identity Federation |
| // |
| // Using workload identity federation, your application can access Google Cloud |
| // resources from Amazon Web Services (AWS), Microsoft Azure or any identity |
| // provider that supports OpenID Connect (OIDC) or SAML 2.0. |
| // Traditionally, applications running outside Google Cloud have used service |
| // account keys to access Google Cloud resources. Using identity federation, |
| // you can allow your workload to impersonate a service account. |
| // This lets you access Google Cloud resources directly, eliminating the |
| // maintenance and security burden associated with service account keys. |
| // |
| // Follow the detailed instructions on how to configure Workload Identity |
| // Federation in various platforms: |
| // |
| // - Amazon Web Services (AWS): https://cloud.google.com/iam/docs/workload-identity-federation-with-other-clouds#aws |
| // - Microsoft Azure: https://cloud.google.com/iam/docs/workload-identity-federation-with-other-clouds#azure |
| // - OIDC identity provider: https://cloud.google.com/iam/docs/workload-identity-federation-with-other-providers#oidc |
| // - SAML 2.0 identity provider: https://cloud.google.com/iam/docs/workload-identity-federation-with-other-providers#saml |
| // |
| // For OIDC and SAML providers, the library can retrieve tokens in fours ways: |
| // from a local file location (file-sourced credentials), from a server |
| // (URL-sourced credentials), from a local executable (executable-sourced |
| // credentials), or from a user defined function that returns an OIDC or SAML token. |
| // For file-sourced credentials, a background process needs to be continuously |
| // refreshing the file location with a new OIDC/SAML token prior to expiration. |
| // For tokens with one hour lifetimes, the token needs to be updated in the file |
| // every hour. The token can be stored directly as plain text or in JSON format. |
| // For URL-sourced credentials, a local server needs to host a GET endpoint to |
| // return the OIDC/SAML token. The response can be in plain text or JSON. |
| // Additional required request headers can also be specified. |
| // For executable-sourced credentials, an application needs to be available to |
| // output the OIDC/SAML token and other information in a JSON format. |
| // For more information on how these work (and how to implement |
| // executable-sourced credentials), please check out: |
| // https://cloud.google.com/iam/docs/workload-identity-federation-with-other-providers#create_a_credential_configuration |
| // |
| // To use a custom function to supply the token, define a struct that implements |
| // the [SubjectTokenProvider] interface for OIDC/SAML providers, or one that |
| // implements [AwsSecurityCredentialsProvider] for AWS providers. This can then |
| // be used when building a [Options].The [cloud.google.com/go/auth.Credentials] |
| // created from the options using [NewCredentials] can then be used to access |
| // Google Cloud resources. For instance, you can create a new client from the |
| // [cloud.google.com/go/storage] package and pass in |
| // option.WithTokenProvider(yourTokenProvider)) |
| // |
| // # Workforce Identity Federation |
| // |
| // Workforce identity federation lets you use an external identity provider |
| // (IdP) to authenticate and authorize a workforce—a group of users, such as |
| // employees, partners, and contractors—using IAM, so that the users can access |
| // Google Cloud services. Workforce identity federation extends Google Cloud's |
| // identity capabilities to support syncless, attribute-based single sign on. |
| // |
| // With workforce identity federation, your workforce can access Google Cloud resources |
| // using an external identity provider (IdP) that supports OpenID Connect (OIDC) or |
| // SAML 2.0 such as Azure Active Directory (Azure AD), Active Directory Federation |
| // Services (AD FS), Okta, and others. |
| // |
| // Follow the detailed instructions on how to configure Workload Identity Federation |
| // in various platforms: |
| // |
| // - [Amazon Web Services (AWS)](https://cloud.google.com/iam/docs/workload-identity-federation-with-other-clouds#aws) |
| // - [Azure AD](https://cloud.google.com/iam/docs/workforce-sign-in-azure-ad) |
| // - [Okta](https://cloud.google.com/iam/docs/workforce-sign-in-okta) |
| // - [OIDC identity provider](https://cloud.google.com/iam/docs/configuring-workforce-identity-federation#oidc) |
| // - [SAML 2.0 identity provider](https://cloud.google.com/iam/docs/configuring-workforce-identity-federation#saml) |
| // |
| // For workforce identity federation, the library can retrieve tokens in three ways: |
| // from a local file location (file-sourced credentials), from a server |
| // (URL-sourced credentials), or from a local executable (executable-sourced |
| // credentials). |
| // For file-sourced credentials, a background process needs to be continuously |
| // refreshing the file location with a new OIDC/SAML token prior to expiration. |
| // For tokens with one hour lifetimes, the token needs to be updated in the file |
| // every hour. The token can be stored directly as plain text or in JSON format. |
| // For URL-sourced credentials, a local server needs to host a GET endpoint to |
| // return the OIDC/SAML token. The response can be in plain text or JSON. |
| // Additional required request headers can also be specified. |
| // For executable-sourced credentials, an application needs to be available to |
| // output the OIDC/SAML token and other information in a JSON format. |
| // For more information on how these work (and how to implement |
| // executable-sourced credentials), please check out: |
| // https://cloud.google.com/iam/docs/workforce-obtaining-short-lived-credentials#generate_a_configuration_file_for_non-interactive_sign-in |
| // |
| // # Security considerations |
| // |
| // Note that this library does not perform any validation on the token_url, |
| // token_info_url, or service_account_impersonation_url fields of the credential |
| // configuration. It is not recommended to use a credential configuration that |
| // you did not generate with the gcloud CLI unless you verify that the URL |
| // fields point to a googleapis.com domain. |
| package externalaccount |
