Add test cases for redirected responses

Regression tests for issue #12744 and PR #19028

test/unit/api_spec.js

@@ -32,6 +32,7 @@ import {
   buildGetDocumentParams,
   CMAP_URL,
   DefaultFileReaderFactory,
+  getCrossOriginHostname,
   TEST_PDFS_PATH,
   TestPdfsServer,
 } from "./test_utils.js";
@@ -2977,17 +2978,14 @@ describe("api", function () {
       let loadingTask;
       function _checkCanLoad(expectSuccess, filename, options) {
         if (isNodeJS) {
+          // We can simulate cross-origin requests, but since Node.js does not
+          // enforce the Same Origin Policy, requests are expected to be allowed
+          // independently of withCredentials.
           pending("Cannot simulate cross-origin requests in Node.js");
         }
         const params = buildGetDocumentParams(filename, options);
         const url = new URL(params.url);
-        if (url.hostname === "localhost") {
-          url.hostname = "127.0.0.1";
-        } else if (params.url.hostname === "127.0.0.1") {
-          url.hostname = "localhost";
-        } else {
-          pending("Can only run cross-origin test on localhost!");
-        }
+        url.hostname = getCrossOriginHostname(url.hostname);
         params.url = url.href;
         loadingTask = getDocument(params);
         return loadingTask.promise

test/unit/common_pdfstream_tests.js

@@ -0,0 +1,90 @@
+/* Copyright 2024 Mozilla Foundation
+ *
+ * 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 { AbortException, isNodeJS } from "../../src/shared/util.js";
+import { getCrossOriginHostname, TestPdfsServer } from "./test_utils.js";
+
+// Common tests to verify behavior across implementations of the IPDFStream
+// interface:
+// - PDFNetworkStream by network_spec.js
+// - PDFFetchStream by fetch_stream_spec.js
+async function testCrossOriginRedirects({
+  PDFStreamClass,
+  redirectIfRange,
+  testRangeReader,
+}) {
+  const basicApiUrl = TestPdfsServer.resolveURL("basicapi.pdf").href;
+  const basicApiFileLength = 105779;
+
+  const rangeSize = 32768;
+  const stream = new PDFStreamClass({
+    url: getCrossOriginUrlWithRedirects(basicApiUrl, redirectIfRange),
+    length: basicApiFileLength,
+    rangeChunkSize: rangeSize,
+    disableStream: true,
+    disableRange: false,
+  });
+
+  const fullReader = stream.getFullReader();
+
+  await fullReader.headersReady;
+  // Sanity check: We can only test range requests if supported:
+  expect(fullReader.isRangeSupported).toEqual(true);
+  // ^ When range requests are supported (and streaming is disabled), the full
+  // initial request is aborted and we do not need to call fullReader.cancel().
+
+  const rangeReader = stream.getRangeReader(
+    basicApiFileLength - rangeSize,
+    basicApiFileLength
+  );
+
+  try {
+    await testRangeReader(rangeReader);
+  } finally {
+    rangeReader.cancel(new AbortException("Don't need rangeReader"));
+  }
+}
+
+/**
+ * @param {string} testserverUrl - A URL handled that supports CORS and
+ *   redirects (see crossOriginHandler and redirectHandler in webserver.mjs).
+ * @param {boolean} redirectIfRange - Whether Range requests should be
+ *   redirected to a different origin compared to the initial request.
+ * @returns {string} A URL that will be redirected by the server.
+ */
+function getCrossOriginUrlWithRedirects(testserverUrl, redirectIfRange) {
+  const url = new URL(testserverUrl);
+  if (!isNodeJS) {
+    // The responses are going to be cross-origin. In Node.js, fetch() allows
+    // cross-origin requests for any request, but in browser environments we
+    // need to enable CORS.
+    // This option depends on crossOriginHandler in webserver.mjs.
+    url.searchParams.set("cors", "withoutCredentials");
+  }
+
+  // This redirect options depend on redirectHandler in webserver.mjs.
+
+  // We will change the host to a cross-origin domain so that the initial
+  // request will be cross-origin. Set "redirectToHost" to the original host
+  // to force a cross-origin redirect (relative to the initial URL).
+  url.searchParams.set("redirectToHost", url.hostname);
+  url.hostname = getCrossOriginHostname(url.hostname);
+  if (redirectIfRange) {
+    url.searchParams.set("redirectIfRange", "1");
+  }
+  return url.href;
+}
+
+export { testCrossOriginRedirects };

test/unit/fetch_stream_spec.js

@@ -15,6 +15,7 @@
 
 import { AbortException } from "../../src/shared/util.js";
 import { PDFFetchStream } from "../../src/display/fetch_stream.js";
+import { testCrossOriginRedirects } from "./common_pdfstream_tests.js";
 import { TestPdfsServer } from "./test_utils.js";
 
 describe("fetch_stream", function () {
@@ -116,4 +117,33 @@ describe("fetch_stream", function () {
     expect(result1.value).toEqual(rangeSize);
     expect(result2.value).toEqual(tailSize);
   });
+
+  describe("Redirects", function () {
+    it("redirects allowed if all responses are same-origin", async function () {
+      await testCrossOriginRedirects({
+        PDFStreamClass: PDFFetchStream,
+        redirectIfRange: false,
+        async testRangeReader(rangeReader) {
+          await expectAsync(rangeReader.read()).toBeResolved();
+        },
+      });
+    });
+
+    it("redirects blocked if any response is cross-origin", async function () {
+      await testCrossOriginRedirects({
+        PDFStreamClass: PDFFetchStream,
+        redirectIfRange: true,
+        async testRangeReader(rangeReader) {
+          // When read (sync), error should be reported.
+          await expectAsync(rangeReader.read()).toBeRejectedWithError(
+            /^Expected range response-origin "http:.*" to match "http:.*"\.$/
+          );
+          // When read again (async), error should be consistent.
+          await expectAsync(rangeReader.read()).toBeRejectedWithError(
+            /^Expected range response-origin "http:.*" to match "http:.*"\.$/
+          );
+        },
+      });
+    });
+  });
 });

test/unit/network_spec.js

@@ -15,6 +15,8 @@
 
 import { AbortException } from "../../src/shared/util.js";
 import { PDFNetworkStream } from "../../src/display/network.js";
+import { testCrossOriginRedirects } from "./common_pdfstream_tests.js";
+import { TestPdfsServer } from "./test_utils.js";
 
 describe("network", function () {
   const pdf1 = new URL("../pdfs/tracemonkey.pdf", window.location).href;
@@ -115,4 +117,41 @@ describe("network", function () {
     expect(isRangeSupported).toEqual(true);
     expect(fullReaderCancelled).toEqual(true);
   });
+
+  describe("Redirects", function () {
+    beforeAll(async function () {
+      await TestPdfsServer.ensureStarted();
+    });
+
+    afterAll(async function () {
+      await TestPdfsServer.ensureStopped();
+    });
+
+    it("redirects allowed if all responses are same-origin", async function () {
+      await testCrossOriginRedirects({
+        PDFStreamClass: PDFNetworkStream,
+        redirectIfRange: false,
+        async testRangeReader(rangeReader) {
+          await expectAsync(rangeReader.read()).toBeResolved();
+        },
+      });
+    });
+
+    it("redirects blocked if any response is cross-origin", async function () {
+      await testCrossOriginRedirects({
+        PDFStreamClass: PDFNetworkStream,
+        redirectIfRange: true,
+        async testRangeReader(rangeReader) {
+          // When read (sync), error should be reported.
+          await expectAsync(rangeReader.read()).toBeRejectedWithError(
+            /^Expected range response-origin "http:.*" to match "http:.*"\.$/
+          );
+          // When read again (async), error should be consistent.
+          await expectAsync(rangeReader.read()).toBeRejectedWithError(
+            /^Expected range response-origin "http:.*" to match "http:.*"\.$/
+          );
+        },
+      });
+    });
+  });
 });

test/unit/test_utils.js

@@ -51,6 +51,22 @@ function buildGetDocumentParams(filename, options) {
   return params;
 }
 
+function getCrossOriginHostname(hostname) {
+  if (hostname === "localhost") {
+    // Note: This does not work if localhost is listening on IPv6 only.
+    // As a work-around, visit the IPv6 version at:
+    // http://[::1]:8888/test/unit/unit_test.html?spec=Cross-origin
+    return "127.0.0.1";
+  }
+
+  if (hostname === "127.0.0.1" || hostname === "[::1]") {
+    return "localhost";
+  }
+
+  // FQDN are cross-origin and browsers usually resolve them to the same server.
+  return hostname.endsWith(".") ? hostname.slice(0, -1) : hostname + ".";
+}
+
 class XRefMock {
   constructor(array) {
     this._map = Object.create(null);
@@ -216,6 +232,7 @@ export {
   CMAP_URL,
   createIdFactory,
   DefaultFileReaderFactory,
+  getCrossOriginHostname,
   STANDARD_FONT_DATA_URL,
   TEST_PDFS_PATH,
   TestPdfsServer,

test/webserver.mjs

@@ -52,7 +52,7 @@ class WebServer {
     this.cacheExpirationTime = cacheExpirationTime || 0;
     this.disableRangeRequests = false;
     this.hooks = {
-      GET: [crossOriginHandler],
+      GET: [crossOriginHandler, redirectHandler],
       POST: [],
     };
   }
@@ -308,6 +308,11 @@ class WebServer {
   }
 
   #serveFileRange(response, fileURL, fileSize, start, end) {
+    if (end > fileSize || start > end) {
+      response.writeHead(416);
+      response.end();
+      return;
+    }
     const stream = fs.createReadStream(fileURL, {
       flags: "rs",
       start,
@@ -336,18 +341,65 @@ class WebServer {
 }
 
 // This supports the "Cross-origin" test in test/unit/api_spec.js
-// It is here instead of test.js so that when the test will still complete as
+// and "Redirects" in test/unit/network_spec.js and
+// test/unit/fetch_stream_spec.js via test/unit/common_pdfstream_tests.js.
+// It is here instead of test.mjs so that when the test will still complete as
 // expected if the user does "gulp server" and then visits
 // http://localhost:8888/test/unit/unit_test.html?spec=Cross-origin
 function crossOriginHandler(url, request, response) {
   if (url.pathname === "/test/pdfs/basicapi.pdf") {
-    if (url.searchParams.get("cors") === "withCredentials") {
-      response.setHeader("Access-Control-Allow-Origin", request.headers.origin);
-      response.setHeader("Access-Control-Allow-Credentials", "true");
-    } else if (url.searchParams.get("cors") === "withoutCredentials") {
-      response.setHeader("Access-Control-Allow-Origin", request.headers.origin);
+    if (!url.searchParams.has("cors") || !request.headers.origin) {
+      return;
     }
+    response.setHeader("Access-Control-Allow-Origin", request.headers.origin);
+    if (url.searchParams.get("cors") === "withCredentials") {
+      response.setHeader("Access-Control-Allow-Credentials", "true");
+    } // withoutCredentials does not include Access-Control-Allow-Credentials.
+    response.setHeader(
+      "Access-Control-Expose-Headers",
+      "Accept-Ranges,Content-Range"
+    );
+    response.setHeader("Vary", "Origin");
   }
 }
 
+// This supports the "Redirects" test in test/unit/network_spec.js and
+// test/unit/fetch_stream_spec.js via test/unit/common_pdfstream_tests.js.
+// It is here instead of test.mjs so that when the test will still complete as
+// expected if the user does "gulp server" and then visits
+// http://localhost:8888/test/unit/unit_test.html?spec=Redirects
+function redirectHandler(url, request, response) {
+  const redirectToHost = url.searchParams.get("redirectToHost");
+  if (redirectToHost) {
+    // Chrome may serve byte range requests directly from the cache, potentially
+    // from a full request or a different range, without involving the server.
+    // To prevent this from happening, make sure that the response is never
+    // cached, so that Range requests are never served from the browser cache.
+    response.setHeader("Cache-Control", "no-store,max-age=0");
+
+    if (url.searchParams.get("redirectIfRange") && !request.headers.range) {
+      return false;
+    }
+    try {
+      const newURL = new URL(url);
+      newURL.hostname = redirectToHost;
+      // Delete test-only query parameters to avoid infinite redirects.
+      newURL.searchParams.delete("redirectToHost");
+      newURL.searchParams.delete("redirectIfRange");
+      if (newURL.hostname !== redirectToHost) {
+        throw new Error(`Invalid hostname: ${redirectToHost}`);
+      }
+      response.setHeader("Location", newURL.href);
+    } catch {
+      response.writeHead(500);
+      response.end();
+      return true;
+    }
+    response.writeHead(302);
+    response.end();
+    return true;
+  }
+  return false;
+}
+
 export { WebServer };