add skip secondary authorization option for public oauth2 clients

models/auth/oauth2.go

@@ -37,10 +37,11 @@ type OAuth2Application struct {
 	// https://datatracker.ietf.org/doc/html/rfc6749#section-2.1
 	// "Authorization servers MUST record the client type in the client registration details"
 	// https://datatracker.ietf.org/doc/html/rfc8252#section-8.4
-	ConfidentialClient bool               `xorm:"NOT NULL DEFAULT TRUE"`
-	RedirectURIs       []string           `xorm:"redirect_uris JSON TEXT"`
-	CreatedUnix        timeutil.TimeStamp `xorm:"INDEX created"`
-	UpdatedUnix        timeutil.TimeStamp `xorm:"INDEX updated"`
+	ConfidentialClient         bool               `xorm:"NOT NULL DEFAULT TRUE"`
+	SkipSecondaryAuthorization bool               `xorm:"NOT NULL DEFAULT FALSE"`
+	RedirectURIs               []string           `xorm:"redirect_uris JSON TEXT"`
+	CreatedUnix                timeutil.TimeStamp `xorm:"INDEX created"`
+	UpdatedUnix                timeutil.TimeStamp `xorm:"INDEX updated"`
 }
 
 func init() {
@@ -251,21 +252,23 @@ func GetOAuth2ApplicationByID(ctx context.Context, id int64) (app *OAuth2Applica
 
 // CreateOAuth2ApplicationOptions holds options to create an oauth2 application
 type CreateOAuth2ApplicationOptions struct {
-	Name               string
-	UserID             int64
-	ConfidentialClient bool
-	RedirectURIs       []string
+	Name                       string
+	UserID                     int64
+	ConfidentialClient         bool
+	SkipSecondaryAuthorization bool
+	RedirectURIs               []string
 }
 
 // CreateOAuth2Application inserts a new oauth2 application
 func CreateOAuth2Application(ctx context.Context, opts CreateOAuth2ApplicationOptions) (*OAuth2Application, error) {
 	clientID := uuid.New().String()
 	app := &OAuth2Application{
-		UID:                opts.UserID,
-		Name:               opts.Name,
-		ClientID:           clientID,
-		RedirectURIs:       opts.RedirectURIs,
-		ConfidentialClient: opts.ConfidentialClient,
+		UID:                        opts.UserID,
+		Name:                       opts.Name,
+		ClientID:                   clientID,
+		RedirectURIs:               opts.RedirectURIs,
+		ConfidentialClient:         opts.ConfidentialClient,
+		SkipSecondaryAuthorization: opts.SkipSecondaryAuthorization,
 	}
 	if err := db.Insert(ctx, app); err != nil {
 		return nil, err
@@ -275,11 +278,12 @@ func CreateOAuth2Application(ctx context.Context, opts CreateOAuth2ApplicationOp
 
 // UpdateOAuth2ApplicationOptions holds options to update an oauth2 application
 type UpdateOAuth2ApplicationOptions struct {
-	ID                 int64
-	Name               string
-	UserID             int64
-	ConfidentialClient bool
-	RedirectURIs       []string
+	ID                         int64
+	Name                       string
+	UserID                     int64
+	ConfidentialClient         bool
+	SkipSecondaryAuthorization bool
+	RedirectURIs               []string
 }
 
 // UpdateOAuth2Application updates an oauth2 application
@@ -305,6 +309,7 @@ func UpdateOAuth2Application(ctx context.Context, opts UpdateOAuth2ApplicationOp
 	app.Name = opts.Name
 	app.RedirectURIs = opts.RedirectURIs
 	app.ConfidentialClient = opts.ConfidentialClient
+	app.SkipSecondaryAuthorization = opts.SkipSecondaryAuthorization
 
 	if err = updateOAuth2Application(ctx, app); err != nil {
 		return nil, err
@@ -315,7 +320,7 @@ func UpdateOAuth2Application(ctx context.Context, opts UpdateOAuth2ApplicationOp
 }
 
 func updateOAuth2Application(ctx context.Context, app *OAuth2Application) error {
-	if _, err := db.GetEngine(ctx).ID(app.ID).UseBool("confidential_client").Update(app); err != nil {
+	if _, err := db.GetEngine(ctx).ID(app.ID).UseBool("confidential_client", "skip_secondary_authorization").Update(app); err != nil {
 		return err
 	}
 	return nil

models/migrations/migrations.go

@@ -591,6 +591,8 @@ var migrations = []Migration{
 
 	// v299 -> v300
 	NewMigration("Add content version to issue and comment table", v1_23.AddContentVersionToIssueAndComment),
+	// v300 -> v301
+	NewMigration("Add skip_secondary_authorization option to oauth2 application table", v1_23.AddSkipSecondaryAuthColumnToOAuth2ApplicationTable),
 }
 
 // GetCurrentDBVersion returns the current db version

models/migrations/v1_23/v300.go

@@ -0,0 +1,16 @@
+// Copyright 2024 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package v1_23 //nolint
+
+import (
+	"xorm.io/xorm"
+)
+
+// AddSkipSeconderyAuthToOAuth2ApplicationTable: add SkipSecondaryAuthorization column, setting existing rows to false
+func AddSkipSecondaryAuthColumnToOAuth2ApplicationTable(x *xorm.Engine) error {
+	type oauth2Application struct {
+		SkipSecondaryAuthorization bool `xorm:"NOT NULL DEFAULT FALSE"`
+	}
+	return x.Sync(new(oauth2Application))
+}

modules/structs/user_app.go

@@ -31,21 +31,23 @@ type CreateAccessTokenOption struct {
 
 // CreateOAuth2ApplicationOptions holds options to create an oauth2 application
 type CreateOAuth2ApplicationOptions struct {
-	Name               string   `json:"name" binding:"Required"`
-	ConfidentialClient bool     `json:"confidential_client"`
-	RedirectURIs       []string `json:"redirect_uris" binding:"Required"`
+	Name                       string   `json:"name" binding:"Required"`
+	ConfidentialClient         bool     `json:"confidential_client"`
+	SkipSecondaryAuthorization bool     `json:"skip_secondary_authorization"`
+	RedirectURIs               []string `json:"redirect_uris" binding:"Required"`
 }
 
 // OAuth2Application represents an OAuth2 application.
 // swagger:response OAuth2Application
 type OAuth2Application struct {
-	ID                 int64     `json:"id"`
-	Name               string    `json:"name"`
-	ClientID           string    `json:"client_id"`
-	ClientSecret       string    `json:"client_secret"`
-	ConfidentialClient bool      `json:"confidential_client"`
-	RedirectURIs       []string  `json:"redirect_uris"`
-	Created            time.Time `json:"created"`
+	ID                         int64     `json:"id"`
+	Name                       string    `json:"name"`
+	ClientID                   string    `json:"client_id"`
+	ClientSecret               string    `json:"client_secret"`
+	ConfidentialClient         bool      `json:"confidential_client"`
+	SkipSecondaryAuthorization bool      `json:"skip_secondary_authorization"`
+	RedirectURIs               []string  `json:"redirect_uris"`
+	Created                    time.Time `json:"created"`
 }
 
 // OAuth2ApplicationList represents a list of OAuth2 applications.

options/locale/locale_en-US.ini

@@ -911,6 +911,7 @@ create_oauth2_application_success = You have successfully created a new OAuth2 a
 update_oauth2_application_success = You have successfully updated the OAuth2 application.
 oauth2_application_name = Application Name
 oauth2_confidential_client = Confidential Client. Select for apps that keep the secret confidential, such as web apps. Do not select for native apps including desktop and mobile apps.
+oauth2_skip_secondary_authorization = Skip authorization for public client after granting access once. <b>May pose a security risk.</b>
 oauth2_redirect_uris = Redirect URIs. Please use a new line for every URI.
 save_application = Save
 oauth2_client_id = Client ID

routers/api/v1/user/app.go

@@ -223,10 +223,11 @@ func CreateOauth2Application(ctx *context.APIContext) {
 	data := web.GetForm(ctx).(*api.CreateOAuth2ApplicationOptions)
 
 	app, err := auth_model.CreateOAuth2Application(ctx, auth_model.CreateOAuth2ApplicationOptions{
-		Name:               data.Name,
-		UserID:             ctx.Doer.ID,
-		RedirectURIs:       data.RedirectURIs,
-		ConfidentialClient: data.ConfidentialClient,
+		Name:                       data.Name,
+		UserID:                     ctx.Doer.ID,
+		RedirectURIs:               data.RedirectURIs,
+		ConfidentialClient:         data.ConfidentialClient,
+		SkipSecondaryAuthorization: data.SkipSecondaryAuthorization,
 	})
 	if err != nil {
 		ctx.Error(http.StatusBadRequest, "", "error creating oauth2 application")
@@ -381,11 +382,12 @@ func UpdateOauth2Application(ctx *context.APIContext) {
 	data := web.GetForm(ctx).(*api.CreateOAuth2ApplicationOptions)
 
 	app, err := auth_model.UpdateOAuth2Application(ctx, auth_model.UpdateOAuth2ApplicationOptions{
-		Name:               data.Name,
-		UserID:             ctx.Doer.ID,
-		ID:                 appID,
-		RedirectURIs:       data.RedirectURIs,
-		ConfidentialClient: data.ConfidentialClient,
+		Name:                       data.Name,
+		UserID:                     ctx.Doer.ID,
+		ID:                         appID,
+		RedirectURIs:               data.RedirectURIs,
+		ConfidentialClient:         data.ConfidentialClient,
+		SkipSecondaryAuthorization: data.SkipSecondaryAuthorization,
 	})
 	if err != nil {
 		if auth_model.IsErrOauthClientIDInvalid(err) || auth_model.IsErrOAuthApplicationNotFound(err) {

routers/web/auth/oauth.go

@@ -470,9 +470,9 @@ func AuthorizeOAuth(ctx *context.Context) {
 		return
 	}
 
-	// Redirect if user already granted access and the application is confidential.
-	// I.e. always require authorization for public clients as recommended by RFC 6749 Section 10.2
-	if app.ConfidentialClient && grant != nil {
+	// Redirect if user already granted access and the application is confidential or trusted otherwise
+	// I.e. always require authorization for untrusted public clients as recommended by RFC 6749 Section 10.2
+	if (app.ConfidentialClient || app.SkipSecondaryAuthorization) && grant != nil {
 		code, err := grant.GenerateNewAuthorizationCode(ctx, form.RedirectURI, form.CodeChallenge, form.CodeChallengeMethod)
 		if err != nil {
 			handleServerError(ctx, form.State, form.RedirectURI)

routers/web/user/setting/oauth2_common.go

@@ -49,10 +49,11 @@ func (oa *OAuth2CommonHandlers) AddApp(ctx *context.Context) {
 
 	// TODO validate redirect URI
 	app, err := auth.CreateOAuth2Application(ctx, auth.CreateOAuth2ApplicationOptions{
-		Name:               form.Name,
-		RedirectURIs:       util.SplitTrimSpace(form.RedirectURIs, "\n"),
-		UserID:             oa.OwnerID,
-		ConfidentialClient: form.ConfidentialClient,
+		Name:                       form.Name,
+		RedirectURIs:               util.SplitTrimSpace(form.RedirectURIs, "\n"),
+		UserID:                     oa.OwnerID,
+		ConfidentialClient:         form.ConfidentialClient,
+		SkipSecondaryAuthorization: form.SkipSecondaryAuthorization,
 	})
 	if err != nil {
 		ctx.ServerError("CreateOAuth2Application", err)
@@ -102,11 +103,12 @@ func (oa *OAuth2CommonHandlers) EditSave(ctx *context.Context) {
 	// TODO validate redirect URI
 	var err error
 	if ctx.Data["App"], err = auth.UpdateOAuth2Application(ctx, auth.UpdateOAuth2ApplicationOptions{
-		ID:                 ctx.PathParamInt64("id"),
-		Name:               form.Name,
-		RedirectURIs:       util.SplitTrimSpace(form.RedirectURIs, "\n"),
-		UserID:             oa.OwnerID,
-		ConfidentialClient: form.ConfidentialClient,
+		ID:                         ctx.PathParamInt64("id"),
+		Name:                       form.Name,
+		RedirectURIs:               util.SplitTrimSpace(form.RedirectURIs, "\n"),
+		UserID:                     oa.OwnerID,
+		ConfidentialClient:         form.ConfidentialClient,
+		SkipSecondaryAuthorization: form.SkipSecondaryAuthorization,
 	}); err != nil {
 		ctx.ServerError("UpdateOAuth2Application", err)
 		return

services/convert/convert.go

@@ -448,13 +448,14 @@ func ToTopicResponse(topic *repo_model.Topic) *api.TopicResponse {
 // ToOAuth2Application convert from auth.OAuth2Application to api.OAuth2Application
 func ToOAuth2Application(app *auth.OAuth2Application) *api.OAuth2Application {
 	return &api.OAuth2Application{
-		ID:                 app.ID,
-		Name:               app.Name,
-		ClientID:           app.ClientID,
-		ClientSecret:       app.ClientSecret,
-		ConfidentialClient: app.ConfidentialClient,
-		RedirectURIs:       app.RedirectURIs,
-		Created:            app.CreatedUnix.AsTime(),
+		ID:                         app.ID,
+		Name:                       app.Name,
+		ClientID:                   app.ClientID,
+		ClientSecret:               app.ClientSecret,
+		ConfidentialClient:         app.ConfidentialClient,
+		SkipSecondaryAuthorization: app.SkipSecondaryAuthorization,
+		RedirectURIs:               app.RedirectURIs,
+		Created:                    app.CreatedUnix.AsTime(),
 	}
 }
 

services/forms/user_form.go

@@ -365,9 +365,10 @@ func (f *NewAccessTokenForm) GetScope() (auth_model.AccessTokenScope, error) {
 
 // EditOAuth2ApplicationForm form for editing oauth2 applications
 type EditOAuth2ApplicationForm struct {
-	Name               string `binding:"Required;MaxSize(255)" form:"application_name"`
-	RedirectURIs       string `binding:"Required" form:"redirect_uris"`
-	ConfidentialClient bool   `form:"confidential_client"`
+	Name                       string `binding:"Required;MaxSize(255)" form:"application_name"`
+	RedirectURIs               string `binding:"Required" form:"redirect_uris"`
+	ConfidentialClient         bool   `form:"confidential_client"`
+	SkipSecondaryAuthorization bool   `form:"skip_secondary_authorization"`
 }
 
 // Validate validates the fields

templates/user/settings/applications_oauth2_edit_form.tmpl

@@ -44,7 +44,13 @@
 		<div class="field {{if .Err_ConfidentialClient}}error{{end}}">
 			<div class="ui checkbox">
 				<label>{{ctx.Locale.Tr "settings.oauth2_confidential_client"}}</label>
-				<input type="checkbox" name="confidential_client" {{if .App.ConfidentialClient}}checked{{end}}>
+				<input class="disable-setting" type="checkbox" name="confidential_client" data-target="#skip-secondary-authorization" {{if .App.ConfidentialClient}}checked{{end}}>
+			</div>
+		</div>
+		<div class="field {{if .Err_SkipSecondaryAuthorization}}error{{end}} {{if .App.ConfidentialClient}}disabled{{end}}" id="skip-secondary-authorization">
+			<div class="ui checkbox">
+				<label>{{ctx.Locale.Tr "settings.oauth2_skip_secondary_authorization"}}</label>
+				<input type="checkbox" name="skip_secondary_authorization" {{if .App.SkipSecondaryAuthorization}}checked{{end}}>
 			</div>
 		</div>
 		<button class="ui primary button">

templates/user/settings/applications_oauth2_list.tmpl

@@ -64,7 +64,13 @@
 		<div class="field {{if .Err_ConfidentialClient}}error{{end}}">
 			<div class="ui checkbox">
 				<label>{{ctx.Locale.Tr "settings.oauth2_confidential_client"}}</label>
-				<input type="checkbox" name="confidential_client" checked>
+				<input class="disable-setting" type="checkbox" name="confidential_client" data-target="#skip-secondary-authorization" checked>
+			</div>
+		</div>
+		<div class="field {{if .Err_SkipSecondaryAuthorization}}error{{end}} disabled" id="skip-secondary-authorization">
+			<div class="ui checkbox">
+				<label>{{ctx.Locale.Tr "settings.oauth2_skip_secondary_authorization"}}</label>
+				<input type="checkbox" name="skip_secondary_authorization">
 			</div>
 		</div>
 		<button class="ui primary button">

web_src/js/features/oauth2-settings.js

@@ -0,0 +1,5 @@
+export function initOAuth2SettingsDisableCheckbox() {
+  for (const e of document.querySelectorAll('.disable-setting')) e.addEventListener('change', ({target}) => {
+    document.querySelector(e.getAttribute('data-target')).classList.toggle('disabled', target.checked);
+  });
+}

web_src/js/index.js

@@ -78,6 +78,7 @@ import {initDirAuto} from './modules/dirauto.js';
 import {initRepositorySearch} from './features/repo-search.js';
 import {initColorPickers} from './features/colorpicker.js';
 import {initAdminSelfCheck} from './features/admin/selfcheck.js';
+import {initOAuth2SettingsDisableCheckbox} from './features/oauth2-settings.js';
 import {initGlobalFetchAction} from './features/common-fetch-action.js';
 import {
   initFootLanguageMenu,
@@ -225,5 +226,7 @@ onDomReady(() => {
     initPdfViewer,
     initScopedAccessTokenCategories,
     initColorPickers,
+
+    initOAuth2SettingsDisableCheckbox,
   ]);
 });