Bug 1631676 - Part 1: add cookie behavior pref getter; r=baku

Differential Revision: https://phabricator.services.mozilla.com/D74049

netwerk/cookie/CookieService.cpp

@@ -30,6 +30,20 @@
 
 using namespace mozilla::dom;
 
+// static
+uint32_t nsICookieManager::GetCookieBehavior() {
+  bool isFirstPartyIsolated = OriginAttributes::IsFirstPartyEnabled();
+  uint32_t cookieBehavior =
+      mozilla::StaticPrefs::network_cookie_cookieBehavior();
+
+  if (isFirstPartyIsolated &&
+      cookieBehavior ==
+          nsICookieService::BEHAVIOR_REJECT_TRACKER_AND_PARTITION_FOREIGN) {
+    cookieBehavior = nsICookieService::BEHAVIOR_REJECT_TRACKER;
+  }
+  return cookieBehavior;
+}
+
 namespace mozilla {
 namespace net {
 
@@ -249,6 +263,13 @@ CookieService::Observe(nsISupports* /*aSubject*/, const char* aTopic,
   return NS_OK;
 }
 
+NS_IMETHODIMP
+CookieService::GetCookieBehavior(uint32_t* aCookieBehavior) {
+  NS_ENSURE_ARG_POINTER(aCookieBehavior);
+  *aCookieBehavior = nsICookieManager::GetCookieBehavior();
+  return NS_OK;
+}
+
 NS_IMETHODIMP
 CookieService::GetCookieStringForPrincipal(nsIPrincipal* aPrincipal,
                                            nsACString& aCookie) {

netwerk/cookie/nsICookieManager.idl

@@ -46,6 +46,14 @@ interface nsICookieManager : nsISupports
    */
   readonly attribute Array<nsICookie> sessionCookies;
 
+  /**
+   * Returns current effective value of the "network.cookie.cookieBehavior".
+   */
+  readonly attribute uint32_t cookieBehavior;
+  %{C++
+    static uint32_t GetCookieBehavior();
+  %}
+
   /**
    * Called to remove an individual cookie from the cookie list, specified
    * by host, name, and path. If the cookie cannot be found, no exception

toolkit/components/antitracking/test/xpcshell/test_cookie_behavior.js

@@ -0,0 +1,40 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// Note: This test may cause intermittents if run at exactly midnight.
+
+"use strict";
+
+const PREF_FPI = "privacy.firstparty.isolate";
+const PREF_COOKIE_BEHAVIOR = "network.cookie.cookieBehavior";
+
+registerCleanupFunction(() => {
+  Services.prefs.clearUserPref(PREF_FPI);
+  Services.prefs.clearUserPref(PREF_COOKIE_BEHAVIOR);
+});
+
+add_task(function test_FPI_off() {
+  Services.prefs.setBoolPref(PREF_FPI, false);
+
+  for (let i = 0; i <= Ci.nsICookieService.BEHAVIOR_LAST; ++i) {
+    Services.prefs.setIntPref(PREF_COOKIE_BEHAVIOR, i);
+    equal(Services.prefs.getIntPref(PREF_COOKIE_BEHAVIOR), i);
+    equal(Services.cookies.cookieBehavior, i);
+  }
+});
+
+add_task(function test_FPI_on() {
+  Services.prefs.setBoolPref(PREF_FPI, true);
+
+  for (let i = 0; i <= Ci.nsICookieService.BEHAVIOR_LAST; ++i) {
+    Services.prefs.setIntPref(PREF_COOKIE_BEHAVIOR, i);
+    equal(Services.prefs.getIntPref(PREF_COOKIE_BEHAVIOR), i);
+    equal(
+      Services.cookies.cookieBehavior,
+      i == Ci.nsICookieService.BEHAVIOR_REJECT_TRACKER_AND_PARTITION_FOREIGN
+        ? Ci.nsICookieService.BEHAVIOR_REJECT_TRACKER
+        : i
+    );
+  }
+});

toolkit/components/antitracking/test/xpcshell/xpcshell.ini

@@ -1,6 +1,7 @@
 [DEFAULT]
 head = head.js ../../../../components/url-classifier/tests/unit/head_urlclassifier.js
 
+[test_cookie_behavior.js]
 [test_purge_trackers.js]
 [test_tracking_db_service.js]
 [test_rejectForeignAllowList.js]