Clean Obsolete HTTP Data from the Password Store

chrome/browser/password_manager/password_manager_util.cc

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/password_manager/password_manager_util.h"
+
+#include <algorithm>
+#include <iterator>
+#include <memory>
+#include <tuple>
+#include <vector>
+
+#include "base/bind.h"
+#include "base/bind_helpers.h"
+#include "base/logging.h"
+#include "base/macros.h"
+#include "base/stl_util.h"
+#include "chrome/browser/password_manager/password_store_factory.h"
+#include "chrome/browser/profiles/profile.h"
+#include "components/autofill/core/common/password_form.h"
+#include "components/keyed_service/core/service_access_type.h"
+#include "components/password_manager/core/browser/password_store.h"
+#include "components/password_manager/core/browser/password_store_consumer.h"
+#include "components/password_manager/core/browser/statistics_table.h"
+#include "components/password_manager/core/common/password_manager_pref_names.h"
+#include "components/prefs/pref_service.h"
+#include "content/public/browser/browser_thread.h"
+#include "net/http/transport_security_state.h"
+#include "net/url_request/url_request_context.h"
+#include "net/url_request/url_request_context_getter.h"
+#include "url/gurl.h"
+
+using autofill::PasswordForm;
+using password_manager::InteractionsStats;
+using password_manager::PasswordStore;
+
+namespace password_manager_util {
+
+namespace {
+
+// Utility function that checks whether HSTS is enabled for a given host.
+// This requires to be passed a URLRequestContextGetter and needs to be called
+// on the IO thread.
+bool IsHSTSActiveForHostAndRequestContext(
+    const GURL& origin,
+    const scoped_refptr<net::URLRequestContextGetter>& request_context) {
+  DCHECK_CURRENTLY_ON(content::BrowserThread::IO);
+  if (!origin.is_valid())
+    return false;
+
+  net::TransportSecurityState* security_state =
+      request_context->GetURLRequestContext()->transport_security_state();
+
+  if (!security_state)
+    return false;
+
+  return security_state->ShouldUpgradeToSSL(origin.host());
+}
+
+// Utility function that moves all elements from a specified iterator into a new
+// vector and returns it. The moved elements are deleted from the original
+// vector.
+std::vector<std::unique_ptr<PasswordForm>> SplitFormsFrom(
+    std::vector<std::unique_ptr<PasswordForm>>::iterator from,
+    std::vector<std::unique_ptr<PasswordForm>>* forms) {
+  const auto end_forms = std::end(*forms);
+  std::vector<std::unique_ptr<PasswordForm>> result;
+  result.reserve(std::distance(from, end_forms));
+  std::move(from, end_forms, std::back_inserter(result));
+  forms->erase(from, end_forms);
+  return result;
+}
+
+void RemoveLoginIfHSTS(const scoped_refptr<PasswordStore>& store,
+                       const PasswordForm& form,
+                       bool is_hsts) {
+  if (is_hsts)
+    store->RemoveLogin(form);
+}
+
+void RemoveSiteStatsIfHSTS(const scoped_refptr<PasswordStore>& store,
+                           const InteractionsStats& stats,
+                           bool is_hsts) {
+  if (is_hsts)
+    store->RemoveSiteStats(stats.origin_domain);
+}
+
+// This class removes obsolete HTTP data from a password store. HTTP data is
+// obsolete, if the corresponding host migrated to HTTPS and has HSTS enabled.
+class ObsoleteHttpCleaner : public password_manager::PasswordStoreConsumer {
+ public:
+  // Constructing a ObsoleteHttpCleaner will result in issuing the clean up
+  // tasks already.
+  explicit ObsoleteHttpCleaner(Profile* profile);
+  ~ObsoleteHttpCleaner() override;
+
+  // PasswordStoreConsumer:
+  // This will be called for both autofillable logins as well as blacklisted
+  // logins. Blacklisted logins are removed iff the scheme is HTTP and HSTS is
+  // enabled for the host.
+  // Autofillable logins are removed iff the scheme is HTTP and there exists
+  // another HTTPS login with active HSTS that has the same host as well as the
+  // same username and password.
+  void OnGetPasswordStoreResults(
+      std::vector<std::unique_ptr<PasswordForm>> results) override;
+
+  // This will remove all stats for HTTP sites for which HSTS is active.
+  void OnGetSiteStatistics(std::vector<InteractionsStats> stats) override;
+
+  Profile* profile() { return profile_; }
+
+  // Returns the PasswordStore associated with |profile_|.
+  PasswordStore* GetPasswordStore() const;
+
+ private:
+  Profile* profile_;
+
+  DISALLOW_COPY_AND_ASSIGN(ObsoleteHttpCleaner);
+};
+
+ObsoleteHttpCleaner::ObsoleteHttpCleaner(Profile* profile) : profile_(profile) {
+  DCHECK(profile_);
+  GetPasswordStore()->GetBlacklistLogins(this);
+  GetPasswordStore()->GetAutofillableLogins(this);
+  GetPasswordStore()->GetAllSiteStats(this);
+}
+
+ObsoleteHttpCleaner::~ObsoleteHttpCleaner() = default;
+
+void ObsoleteHttpCleaner::OnGetPasswordStoreResults(
+    std::vector<std::unique_ptr<PasswordForm>> results) {
+  // Non HTTP or HTTPS credentials are ignored.
+  base::EraseIf(results, [](const std::unique_ptr<PasswordForm>& form) {
+    return !form->origin.SchemeIsHTTPOrHTTPS();
+  });
+
+  // Move HTTPS forms into their own container.
+  auto https_forms = SplitFormsFrom(
+      std::partition(std::begin(results), std::end(results),
+                     [](const std::unique_ptr<PasswordForm>& form) {
+                       return form->origin.SchemeIs(url::kHttpScheme);
+                     }),
+      &results);
+
+  // Move blacklisted HTTP forms into their own container.
+  const auto blacklisted_http_forms = SplitFormsFrom(
+      std::partition(std::begin(results), std::end(results),
+                     [](const std::unique_ptr<PasswordForm>& form) {
+                       return !form->blacklisted_by_user;
+                     }),
+      &results);
+
+  // Remove blacklisted HTTP forms from the password store when HSTS is active
+  // for the given host.
+  for (const auto& form : blacklisted_http_forms) {
+    PostHSTSQueryForHostAndProfile(
+        form->origin, profile(),
+        base::Bind(&RemoveLoginIfHSTS, make_scoped_refptr(GetPasswordStore()),
+                   *form));
+  }
+
+  // Return early if there are no non-blacklisted HTTP forms.
+  if (results.empty())
+    return;
+
+  // Sort HTTPS forms according to custom comparison function. Consider two
+  // forms equivalent if they have the same host, as well as the same username
+  // and password.
+  const auto form_cmp = [](const std::unique_ptr<PasswordForm>& lhs,
+                           const std::unique_ptr<PasswordForm>& rhs) {
+    return std::forward_as_tuple(lhs->origin.host_piece(), lhs->username_value,
+                                 lhs->password_value) <
+           std::forward_as_tuple(rhs->origin.host_piece(), rhs->username_value,
+                                 rhs->password_value);
+  };
+
+  std::sort(std::begin(https_forms), std::end(https_forms), form_cmp);
+
+  // Iterate through HTTP forms and remove them from the password store if there
+  // exists an equivalent HTTPS form that has HSTS enabled.
+  for (const auto& form : results) {
+    if (std::binary_search(std::begin(https_forms), std::end(https_forms), form,
+                           form_cmp)) {
+      PostHSTSQueryForHostAndProfile(
+          form->origin, profile(),
+          base::Bind(&RemoveLoginIfHSTS, make_scoped_refptr(GetPasswordStore()),
+                     *form));
+    }
+  }
+}
+
+void ObsoleteHttpCleaner::OnGetSiteStatistics(
+    std::vector<InteractionsStats> stats) {
+  for (const auto& stat : stats) {
+    if (stat.origin_domain.SchemeIs(url::kHttpScheme)) {
+      PostHSTSQueryForHostAndProfile(
+          stat.origin_domain, profile(),
+          base::Bind(&RemoveSiteStatsIfHSTS,
+                     make_scoped_refptr(GetPasswordStore()), stat));
+    }
+  }
+}
+
+PasswordStore* ObsoleteHttpCleaner::GetPasswordStore() const {
+  return PasswordStoreFactory::GetForProfile(profile_,
+                                             ServiceAccessType::EXPLICIT_ACCESS)
+      .get();
+}
+
+void WaitUntilCleaningIsDone(std::unique_ptr<ObsoleteHttpCleaner> cleaner) {
+  // Given the async nature of the cleaning tasks it is non-trivial to determine
+  // when they are all done. In this method we make use of the fact that as long
+  // the cleaning is not completed, weak pointers to the cleaner object exist
+  // (the scheduled, but not yet executed tasks hold them). If the cleaning is
+  // not done yet, this method schedules a task on the password store, which
+  // will be behind the cleaning tasks in the task queue. When the scheduled
+  // task gets executed, this method is called again. Now it is guaranteed that
+  // the initial scheduled cleaning tasks will have been executed, but it might
+  // be the case that they wait for the result of other scheduled tasks (e.g. on
+  // Windows there could be async calls to GetIE7Login). In this case another
+  // round trip of tasks will be scheduled. Finally, when no weak ptrs remain,
+  // this method sets a boolean preference flag and returns.
+  if (cleaner->HasWeakPtrs()) {
+    const auto post_to_ui_thread =
+        [](std::unique_ptr<ObsoleteHttpCleaner> cleaner) {
+          content::BrowserThread::PostTask(
+              content::BrowserThread::UI, FROM_HERE,
+              base::Bind(&WaitUntilCleaningIsDone,
+                         base::Passed(std::move(cleaner))));
+        };
+
+    cleaner->GetPasswordStore()->ScheduleTask(
+        base::Bind(post_to_ui_thread, base::Passed(std::move(cleaner))));

[jdoerrie, 2017/03/23 15:42:12]

I briefly talked with Vasilii about this: This would be cleaner if we could call
|PostTaskAndReply| directly on PasswordStore's task runner. However, this is
currently not possible, since |PasswordStore::GetBackgroundTaskRunner| is
protected. Vasilii wasn't sure whether this usecase would be enough of a
justification to make the method public. What do you think, vabr@?

[vasilii, 2017/03/23 17:39:26]

I'm against expanding the public part of PasswordStore given that ScheduleTask
works fine.

+    return;
+  }
+
+  cleaner->profile()->GetPrefs()->SetBoolean(
+      password_manager::prefs::kWasObsoleteHttpDataCleaned, true);
+}
+
+void CleanObsoleteHttpDataForProfile(Profile* profile) {
+  if (!profile->GetPrefs()->GetBoolean(
+          password_manager::prefs::kWasObsoleteHttpDataCleaned)) {
+    WaitUntilCleaningIsDone(base::MakeUnique<ObsoleteHttpCleaner>(profile));
+  }
+}
+
+}  // namespace
+
+void PostHSTSQueryForHostAndProfile(const GURL& origin,
+                                    Profile* profile,
+                                    const HSTSCallback& callback) {
+  content::BrowserThread::PostTaskAndReplyWithResult(
+      content::BrowserThread::IO, FROM_HERE,
+      base::Bind(&IsHSTSActiveForHostAndRequestContext, origin,
+                 make_scoped_refptr(profile->GetRequestContext())),
+      callback);
+}
+
+void DelayCleanObsoleteHttpDataForProfile(Profile* profile,
+                                          int delay_in_seconds) {
+  content::BrowserThread::PostDelayedTask(
+      content::BrowserThread::UI, FROM_HERE,
+      base::Bind(&CleanObsoleteHttpDataForProfile, profile),
+      base::TimeDelta::FromSeconds(delay_in_seconds));
+}
+
+}  // namespace password_manager_util