diff --git a/plugins/auth-node/src/oauth/OAuthCookieManager.ts b/plugins/auth-node/src/oauth/OAuthCookieManager.ts new file mode 100644 index 0000000000..5fe2304610 --- /dev/null +++ b/plugins/auth-node/src/oauth/OAuthCookieManager.ts @@ -0,0 +1,127 @@ +/* + * Copyright 2023 The Backstage Authors + * + * 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. + */ + +import { Request, Response } from 'express'; +import { CookieConfigurer } from '../types'; + +const THOUSAND_DAYS_MS = 1000 * 24 * 60 * 60 * 1000; +const TEN_MINUTES_MS = 600 * 1000; + +const defaultCookieConfigurer: CookieConfigurer = ({ + callbackUrl, + providerId, + appOrigin, +}) => { + const { hostname: domain, pathname, protocol } = new URL(callbackUrl); + const secure = protocol === 'https:'; + + // For situations where the auth-backend is running on a + // different domain than the app, we set the SameSite attribute + // to 'none' to allow third-party access to the cookie, but + // only if it's in a secure context (https). + let sameSite: ReturnType['sameSite'] = 'lax'; + if (new URL(appOrigin).hostname !== domain && secure) { + sameSite = 'none'; + } + + // If the provider supports callbackUrls, the pathname will + // contain the complete path to the frame handler so we need + // to slice off the trailing part of the path. + const path = pathname.endsWith(`${providerId}/handler/frame`) + ? pathname.slice(0, -'/handler/frame'.length) + : `${pathname}/${providerId}`; + + return { domain, path, secure, sameSite }; +}; + +/** @internal */ +export class OAuthCookieManager { + private readonly cookieConfigurer: CookieConfigurer; + private readonly nonceCookie: string; + private readonly refreshTokenCookie: string; + private readonly grantedScopeCookie: string; + + constructor( + private readonly options: { + providerId: string; + defaultAppOrigin: string; + baseUrl: string; + callbackUrl: string; + cookieConfigurer?: CookieConfigurer; + }, + ) { + this.cookieConfigurer = options.cookieConfigurer ?? defaultCookieConfigurer; + + this.nonceCookie = `${options.providerId}-nonce`; + this.refreshTokenCookie = `${options.providerId}-refresh-token`; + this.grantedScopeCookie = `${options.providerId}-granted-scope`; + } + + private getConfig(origin?: string, pathSuffix: string = '') { + const cookieConfig = this.cookieConfigurer({ + providerId: this.options.providerId, + baseUrl: this.options.baseUrl, + callbackUrl: this.options.callbackUrl, + appOrigin: origin ?? this.options.defaultAppOrigin, + }); + return { + httpOnly: true, + sameSite: 'lax' as const, + ...cookieConfig, + path: cookieConfig.path + pathSuffix, + }; + } + + setNonce(res: Response, nonce: string, origin?: string) { + res.cookie(this.nonceCookie, nonce, { + maxAge: TEN_MINUTES_MS, + ...this.getConfig(origin, '/handler'), + }); + } + + setRefreshToken(res: Response, refreshToken: string, origin?: string) { + res.cookie(this.refreshTokenCookie, refreshToken, { + maxAge: THOUSAND_DAYS_MS, + ...this.getConfig(origin), + }); + } + + removeRefreshToken(res: Response, origin?: string) { + res.cookie(this.refreshTokenCookie, '', { + maxAge: 0, + ...this.getConfig(origin), + }); + } + + setGrantedScopes(res: Response, scope: string, origin?: string) { + res.cookie(this.grantedScopeCookie, scope, { + maxAge: THOUSAND_DAYS_MS, + ...this.getConfig(origin), + }); + } + + getNonce(req: Request) { + return req.cookies[this.nonceCookie]; + } + + getRefreshToken(req: Request) { + return req.cookies[this.refreshTokenCookie]; + } + + getGrantedScopes(req: Request) { + return req.cookies[this.grantedScopeCookie]; + } +}