Bug 1927219 - Set consistent opener policy for printing. r=nika

Differential Revision: https://phabricator.services.mozilla.com/D226964

docshell/base/BrowsingContext.cpp

@@ -420,6 +420,10 @@ already_AddRefed<BrowsingContext> BrowsingContext::CreateDetached(
         topPolicy == nsILoadInfo::OPENER_POLICY_UNSAFE_NONE ||
         topPolicy == nsILoadInfo::OPENER_POLICY_SAME_ORIGIN_ALLOW_POPUPS ||
         aOptions.isForPrinting);
+    if (aOptions.isForPrinting) {
+      // Ensure our opener policy is consistent for printing for our top.
+      fields.Get<IDX_OpenerPolicy>() = topPolicy;
+    }
   } else if (!aParent && group->IsPotentiallyCrossOriginIsolated()) {
     // If we're creating a brand-new toplevel BC in a potentially cross-origin
     // isolated group, it should start out with a strict opener policy.

testing/mochitest/document-builder.sjs

@@ -69,17 +69,19 @@ async function handleRequest(request, response) {
     });
   }
 
-  response.setHeader("Cache-Control", "no-cache", false);
-  if (html) {
-    response.setHeader("Content-Type", "text/html", false);
-
+  function setHeaders() {
     if (queryString.has("headers")) {
       for (const header of queryString.getAll("headers")) {
         const [key, value] = header.split(":");
         response.setHeader(key, value, false);
       }
     }
+  }
 
+  response.setHeader("Cache-Control", "no-cache", false);
+  if (html) {
+    response.setHeader("Content-Type", "text/html", false);
+    setHeaders();
     response.write(html);
   } else {
     const path = queryString.get("file");
@@ -89,6 +91,7 @@ async function handleRequest(request, response) {
       path.endsWith(".xhtml") ? "application/xhtml+xml" : "text/html",
       false
     );
+    setHeaders();
     // This is a hack to set the correct id for the content document that is to be
     // loaded in the iframe.
     response.write(doc.replace(`id="body"`, `id="default-iframe-body-id"`));

toolkit/components/printing/tests/browser.toml

@@ -43,8 +43,7 @@ support-files = ["file_link_modulepreload.html"]
 
 ["browser_print_coop.js"]
 support-files = [
-  "file_coop_header.html",
-  "file_coop_header.html^headers^",
+  "file_print_coop_helper.html",
 ]
 
 ["browser_print_copies.js"]

toolkit/components/printing/tests/browser_print_coop.js

@@ -13,23 +13,29 @@ const TEST_PATH_SITE = getRootDirectory(gTestPath).replace(
   "https://test1.example.com"
 );
 
-// Verify if the page with a COOP header can be used for printing preview.
-add_task(async function test_print_coop_basic() {
-  await PrintHelper.withTestPage(async helper => {
-    await helper.startPrint();
-    ok(true, "We did not crash.");
-    await helper.closeDialog();
-  }, "file_coop_header.html");
-});
+const COOP_HELPER_FILE =
+  getRootDirectory(gTestPath).replace("chrome://mochitests/content/", "") +
+  "file_print_coop_helper.html";
 
-add_task(async function test_window_print_coop() {
-  for (const base of [TEST_PATH, TEST_PATH_SITE]) {
-    for (const query of [
+async function test_print_flags_with_headers(headers, expectIsolated) {
+  let params = new URLSearchParams({
+    file: COOP_HELPER_FILE,
+  });
+  for (let header of headers) {
+    params.append("headers", header);
+  }
+  for (const origin of ["https://example.com", "https://test1.example.com"]) {
+    for (const hash of [
       "print",
       "print-same-origin-frame",
+      "print-same-origin-frame-srcdoc",
       "print-cross-origin-frame",
     ]) {
-      const url = `${base}file_coop_header.html?${query}`;
+      if (expectIsolated && hash == "print-cross-origin-frame") {
+        // The iframe wouldn't load.
+        continue;
+      }
+      let url = `${origin}/document-builder.sjs?${params}#${hash}`;
       info(`Testing ${url}`);
       is(
         document.querySelector(".printPreviewBrowser"),
@@ -47,7 +53,28 @@ add_task(async function test_window_print_coop() {
 
         ok(true, "Shouldn't crash");
         gBrowser.getTabDialogBox(browser).abortAllDialogs();
+        let isolated = await SpecialPowers.spawn(browser, [], () => {
+          return content.crossOriginIsolated;
+        });
+        is(isolated, expectIsolated, "Expected isolation");
       });
     }
   }
+}
+
+add_task(async function test_window_print_coop() {
+  return test_print_flags_with_headers(
+    ["Cross-Origin-Opener-Policy: same-origin"],
+    /* expectIsolated = */ false
+  );
+});
+
+add_task(async function test_window_print_coep() {
+  return test_print_flags_with_headers(
+    [
+      "Cross-Origin-Opener-Policy: same-origin",
+      "Cross-Origin-Embedder-Policy: require-corp",
+    ],
+    /* expectIsolated = */ true
+  );
 });

toolkit/components/printing/tests/file_coop_header.html

@@ -1,20 +0,0 @@
-<!DOCTYPE html>
-<meta charset="utf-8">
-<p>Hello world</p>
-<iframe id="iframe"></iframe>
-<script>
-onload = function() {
-  let iframe = document.getElementById("iframe");
-  switch (location.search) {
-    case "?print":
-      window.print();
-      break;
-    case "?print-same-origin-frame":
-      iframe.src = `/document-builder.sjs?html=Hello<script>print()<\/script>`;
-      break;
-    case "?print-cross-origin-frame":
-      iframe.src = `https://example.org/document-builder.sjs?html=Hello<script>print()<\/script>`;
-      break;
-  }
-}
-</script>

toolkit/components/printing/tests/file_coop_header.html^headers^

@@ -1 +0,0 @@
-Cross-Origin-Opener-Policy: same-origin

toolkit/components/printing/tests/file_print_coop_helper.html

@@ -0,0 +1,27 @@
+<!DOCTYPE html>
+<meta charset="utf-8">
+<p>Hello world</p>
+<iframe id="iframe"></iframe>
+<script>
+onload = function() {
+  let iframe = document.getElementById("iframe");
+  switch (location.hash) {
+    case "#print":
+      window.print();
+      break;
+    case "#print-same-origin-frame": {
+      let params = new URLSearchParams(location.search);
+      params.delete("file");
+      params.set("html", "Hello<script>print()<\/script>");
+      iframe.src = `/document-builder.sjs?${params}`;
+      break;
+    }
+    case "#print-same-origin-frame-srcdoc":
+      iframe.srcdoc = `Hello<script>print()<\/script>`;
+      break;
+    case "#print-cross-origin-frame":
+      iframe.src = `https://example.org/document-builder.sjs?html=Hello<script>print()<\/script>`;
+      break;
+  }
+}
+</script>