Bug 1729640 - P4. Setting high-value permission for sites that are considered is logged in. r=farre,sfoster,tgiles

Sites that match the following heuristic are considered high-value:
1. Sites that have a password stored in the password manager
2. Sites that we detect that users submit a form with a password

This patch adds LoginDetectionService to detect login attempts.
When LoginDetectionService finds a site that matches any of the above
heuristics, it adds the corresponding high-value permission to the
permission manager.

Differential Revision: https://phabricator.services.mozilla.com/D127105

browser/components/BrowserGlue.jsm

@@ -2673,6 +2673,16 @@ BrowserGlue.prototype = {
         },
       },
 
+      // Login detection service is used in fission to identify high value sites.
+      {
+        task: () => {
+          let loginDetection = Cc[
+            "@mozilla.org/login-detection-service;1"
+          ].createInstance(Ci.nsILoginDetectionService);
+          loginDetection.init();
+        },
+      },
+
       // WebDriver components (Remote Agent and Marionette) need to be
       // initialized as very last step.
       {

dom/ipc/LoginDetectionService.cpp

@@ -0,0 +1,137 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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/. */
+
+#include "LoginDetectionService.h"
+
+#include "nsILoginInfo.h"
+#include "nsILoginManager.h"
+#include "nsIObserver.h"
+#include "nsIXULRuntime.h"
+#include "nsServiceManagerUtils.h"
+#include "nsXULAppAPI.h"
+
+#include "mozilla/ClearOnShutdown.h"
+#include "mozilla/StaticPrefs_fission.h"
+#include "mozilla/dom/ProcessIsolation.h"
+
+namespace mozilla::dom {
+
+static StaticRefPtr<LoginDetectionService> gLoginDetectionService;
+
+namespace {
+
+void OnFissionPrefsChange(const char* aPrefName, void* aData) {
+  MOZ_ASSERT(gLoginDetectionService);
+
+  gLoginDetectionService->MaybeStartMonitoring();
+}
+
+}  // namespace
+
+NS_IMPL_ISUPPORTS(LoginDetectionService, nsILoginDetectionService,
+                  nsILoginSearchCallback, nsIObserver, nsISupportsWeakReference)
+
+// static
+already_AddRefed<LoginDetectionService> LoginDetectionService::GetSingleton() {
+  if (gLoginDetectionService) {
+    return do_AddRef(gLoginDetectionService);
+  }
+
+  gLoginDetectionService = new LoginDetectionService();
+  ClearOnShutdown(&gLoginDetectionService);
+
+  return do_AddRef(gLoginDetectionService);
+}
+
+LoginDetectionService::~LoginDetectionService() { UnregisterObserver(); }
+
+void LoginDetectionService::MaybeStartMonitoring() {
+  if (IsIsolateHighValueSiteEnabled()) {
+    // We want to isolate sites with a saved password, so fetch saved logins
+    // from the password manager, and then add the 'HighValue' permission.
+
+    // Note that we don't monitor whether a login is added or removed after
+    // logins are fetched. For adding logins, this will be covered by form
+    // submission detection heuristic. As for removing logins, it doesn't
+    // provide security benefit just to NOT isolate the removed site. The site
+    // will not be isolated when its permission expired.
+    FetchLogins();
+
+    if (!mObs) {
+      mObs = mozilla::services::GetObserverService();
+      mObs->AddObserver(this, "passwordmgr-form-submission-detected", false);
+    }
+  } else {
+    UnregisterObserver();
+  }
+}
+
+void LoginDetectionService::FetchLogins() {
+  nsresult rv;
+  nsCOMPtr<nsILoginManager> loginManager =
+      do_GetService(NS_LOGINMANAGER_CONTRACTID, &rv);
+  if (NS_WARN_IF(!loginManager)) {
+    return;
+  }
+
+  Unused << loginManager->GetAllLoginsWithCallbackAsync(this);
+}
+
+void LoginDetectionService::UnregisterObserver() {
+  if (mObs) {
+    mObs->RemoveObserver(this, "passwordmgr-form-submission-detected");
+    mObs = nullptr;
+  }
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// nsILoginDetectionService implementation
+NS_IMETHODIMP LoginDetectionService::Init() {
+  if (XRE_IsContentProcess()) {
+    return NS_OK;
+  }
+
+  Preferences::RegisterCallback(OnFissionPrefsChange, "fission.autostart");
+  Preferences::RegisterCallback(OnFissionPrefsChange,
+                                "fission.webContentIsolationStrategy");
+
+  MaybeStartMonitoring();
+
+  return NS_OK;
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// nsILoginSearchObserver implementation
+NS_IMETHODIMP
+LoginDetectionService::OnSearchComplete(
+    const nsTArray<RefPtr<nsILoginInfo>>& aLogins) {
+  // Add all origins with saved passwords to the permission manager.
+  for (const auto& login : aLogins) {
+    nsString origin;
+    login->GetOrigin(origin);
+
+    AddHighValuePermission(NS_ConvertUTF16toUTF8(origin),
+                           mozilla::dom::kHighValueHasSavedLoginPermission);
+  }
+
+  return NS_OK;
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// nsIObserver implementation
+NS_IMETHODIMP
+LoginDetectionService::Observe(nsISupports* aSubject, const char* aTopic,
+                               const char16_t* aData) {
+  if ("passwordmgr-form-submission-detected"_ns.Equals(aTopic)) {
+    nsDependentString origin(aData);
+    AddHighValuePermission(NS_ConvertUTF16toUTF8(origin),
+                           mozilla::dom::kHighValueIsLoggedInPermission);
+  }
+
+  return NS_OK;
+}
+
+}  // namespace mozilla::dom

dom/ipc/LoginDetectionService.h

@@ -0,0 +1,57 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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/. */
+
+#ifndef mozilla_dom_LoginDetectionService_h
+#define mozilla_dom_LoginDetectionService_h
+
+#include "nsIObserver.h"
+#include "nsIObserverService.h"
+#include "nsILoginDetectionService.h"
+#include "nsILoginManager.h"
+#include "nsWeakReference.h"
+#include "mozilla/Logging.h"
+#include "mozilla/Preferences.h"
+
+namespace mozilla::dom {
+
+/**
+ * Detect whether the user is 'possibly' logged in to a site, and add the
+ * HighValue permission to the permission manager. We say 'possibly' because
+ * the detection is done in a very loose way. For example, for sites that have
+ * an associated login stored in the password manager are considered `logged in`
+ * by the service, which is not always true in terms of whether the users is
+ * really logged in to the site.
+ */
+class LoginDetectionService final : public nsILoginDetectionService,
+                                    public nsILoginSearchCallback,
+                                    public nsIObserver,
+                                    public nsSupportsWeakReference {
+ public:
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSILOGINDETECTIONSERVICE
+  NS_DECL_NSILOGINSEARCHCALLBACK
+  NS_DECL_NSIOBSERVER
+
+  static already_AddRefed<LoginDetectionService> GetSingleton();
+
+  void MaybeStartMonitoring();
+
+ private:
+  LoginDetectionService() = default;
+  virtual ~LoginDetectionService();
+
+  // Fetch saved logins from the password manager.
+  void FetchLogins();
+
+  void RegisterObserver();
+  void UnregisterObserver();
+
+  nsCOMPtr<nsIObserverService> mObs;
+};
+
+}  // namespace mozilla::dom
+
+#endif

dom/ipc/ProcessIsolation.cpp

@@ -955,4 +955,24 @@ void AddHighValuePermission(nsIPrincipal* aResultPrincipal,
       nsIPermissionManager::EXPIRE_TIME, expirationTime);
 }
 
+void AddHighValuePermission(const nsACString& aOrigin,
+                            const nsACString& aPermissionType) {
+  nsIScriptSecurityManager* ssm = nsContentUtils::GetSecurityManager();
+  nsCOMPtr<nsIPrincipal> principal;
+  nsresult rv =
+      ssm->CreateContentPrincipalFromOrigin(aOrigin, getter_AddRefs(principal));
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return;
+  }
+
+  AddHighValuePermission(principal, aPermissionType);
+}
+
+bool IsIsolateHighValueSiteEnabled() {
+  return mozilla::FissionAutostart() &&
+         WebContentIsolationStrategy(
+             StaticPrefs::fission_webContentIsolationStrategy()) ==
+             WebContentIsolationStrategy::IsolateHighValue;
+}
+
 }  // namespace mozilla::dom

dom/ipc/ProcessIsolation.h

@@ -13,9 +13,8 @@
 #include "mozilla/dom/RemoteType.h"
 #include "mozilla/dom/SessionHistoryEntry.h"
 #include "nsString.h"
-
-class nsIURI;
-class nsIPrincipal;
+#include "nsIPrincipal.h"
+#include "nsIURI.h"
 
 namespace mozilla::dom {
 
@@ -80,6 +79,15 @@ Result<NavigationIsolationOptions, nsresult> IsolationOptionsForNavigation(
 void AddHighValuePermission(nsIPrincipal* aResultPrincipal,
                             const nsACString& aPermissionType);
 
+void AddHighValuePermission(const nsACString& aOrigin,
+                            const nsACString& aPermissionType);
+
+/**
+ * Returns true when fission is enabled and the
+ * `fission.webContentIsolationStrategy` pref is set to `IsolateHighValue`.
+ */
+bool IsIsolateHighValueSiteEnabled();
+
 }  // namespace mozilla::dom
 
 #endif

dom/ipc/components.conf

@@ -0,0 +1,16 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# 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/.
+
+Classes = [
+    {
+        'cid': '{91fdaa4e-eba4-4ed3-831c-ce05c142822d}',
+        'contract_ids': ['@mozilla.org/login-detection-service;1'],
+        'type': 'mozilla::dom::LoginDetectionService',
+        'singleton': True,
+        'headers': ['/dom/ipc/LoginDetectionService.h'],
+        'constructor': 'mozilla::dom::LoginDetectionService::GetSingleton',
+    },
+]

dom/ipc/moz.build

@@ -13,10 +13,15 @@ XPIDL_SOURCES += [
     "nsIDOMProcessChild.idl",
     "nsIDOMProcessParent.idl",
     "nsIHangReport.idl",
+    "nsILoginDetectionService.idl",
 ]
 
 XPIDL_MODULE = "dom"
 
+XPCOM_MANIFESTS += [
+    "components.conf",
+]
+
 EXTRA_JS_MODULES += [
     "ManifestMessagesChild.jsm",
 ]
@@ -53,6 +58,7 @@ EXPORTS.mozilla.dom += [
     "FilePickerParent.h",
     "InProcessChild.h",
     "InProcessParent.h",
+    "LoginDetectionService.h",
     "MaybeDiscarded.h",
     "MemoryReportRequest.h",
     "NativeThreadId.h",
@@ -106,6 +112,7 @@ UNIFIED_SOURCES += [
     "DocShellMessageUtils.cpp",
     "FilePickerParent.cpp",
     "InProcessImpl.cpp",
+    "LoginDetectionService.cpp",
     "MemMapSnapshot.cpp",
     "MemoryReportRequest.cpp",
     "MMPrinter.cpp",

dom/ipc/nsILoginDetectionService.idl

@@ -0,0 +1,16 @@
+/* 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/. */
+
+#include "nsISupports.idl"
+
+interface nsIURI;
+
+[scriptable, uuid(4c3c9a82-722a-4b0b-9c7d-36ef90135537)]
+interface nsILoginDetectionService : nsISupports
+{
+  /**
+   * called to initialize the login detection service.
+   */
+  void init();
+};