auth-node: add OAuthCookieManager

Signed-off-by: Patrik Oldsberg <poldsberg@gmail.com>
2023-07-22 10:44:55 +02:00
parent 6c7952ee85
commit 93427ba7bc
1 changed files with 127 additions and 0 deletions
@@ -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<CookieConfigurer>['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];
+  }
+}