// Copyright (c) 2012 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/native_backend_gnome_x.h"

#include <dlfcn.h>
#include <gnome-keyring.h>

#include <map>
#include <string>
#include <vector>

#include "base/basictypes.h"
#include "base/logging.h"
#include "base/memory/scoped_ptr.h"
#include "base/metrics/histogram.h"
#include "base/strings/string_number_conversions.h"
#include "base/strings/string_piece.h"
#include "base/strings/string_util.h"
#include "base/strings/stringprintf.h"
#include "base/strings/utf_string_conversions.h"
#include "base/synchronization/waitable_event.h"
#include "base/time/time.h"
#include "components/autofill/core/common/password_form.h"
#include "components/password_manager/core/browser/psl_matching_helper.h"
#include "content/public/browser/browser_thread.h"

using autofill::PasswordForm;
using base::UTF8ToUTF16;
using base::UTF16ToUTF8;
using content::BrowserThread;
using password_manager::PSLMatchingHelper;

#define GNOME_KEYRING_DEFINE_POINTER(name) \
  typeof(&::gnome_keyring_##name) GnomeKeyringLoader::gnome_keyring_##name;
GNOME_KEYRING_FOR_EACH_FUNC(GNOME_KEYRING_DEFINE_POINTER)
#undef GNOME_KEYRING_DEFINE_POINTER

bool GnomeKeyringLoader::keyring_loaded = false;

#if defined(DLOPEN_GNOME_KEYRING)

#define GNOME_KEYRING_FUNCTION_INFO(name) \
  {"gnome_keyring_"#name, reinterpret_cast<void**>(&gnome_keyring_##name)},
const GnomeKeyringLoader::FunctionInfo GnomeKeyringLoader::functions[] = {
  GNOME_KEYRING_FOR_EACH_FUNC(GNOME_KEYRING_FUNCTION_INFO)
  {NULL, NULL}
};
#undef GNOME_KEYRING_FUNCTION_INFO

/* Load the library and initialize the function pointers. */
bool GnomeKeyringLoader::LoadGnomeKeyring() {
  if (keyring_loaded)
    return true;

  void* handle = dlopen("libgnome-keyring.so.0", RTLD_NOW | RTLD_GLOBAL);
  if (!handle) {
    // We wanted to use GNOME Keyring, but we couldn't load it. Warn, because
    // either the user asked for this, or we autodetected it incorrectly. (Or
    // the system has broken libraries, which is also good to warn about.)
    LOG(WARNING) << "Could not load libgnome-keyring.so.0: " << dlerror();
    return false;
  }

  for (size_t i = 0; functions[i].name; ++i) {
    dlerror();
    *functions[i].pointer = dlsym(handle, functions[i].name);
    const char* error = dlerror();
    if (error) {
      LOG(ERROR) << "Unable to load symbol "
                 << functions[i].name << ": " << error;
      dlclose(handle);
      return false;
    }
  }

  keyring_loaded = true;
  // We leak the library handle. That's OK: this function is called only once.
  return true;
}

#else  // defined(DLOPEN_GNOME_KEYRING)

bool GnomeKeyringLoader::LoadGnomeKeyring() {
  if (keyring_loaded)
    return true;
#define GNOME_KEYRING_ASSIGN_POINTER(name) \
  gnome_keyring_##name = &::gnome_keyring_##name;
  GNOME_KEYRING_FOR_EACH_FUNC(GNOME_KEYRING_ASSIGN_POINTER)
#undef GNOME_KEYRING_ASSIGN_POINTER
  keyring_loaded = true;
  return true;
}

#endif  // defined(DLOPEN_GNOME_KEYRING)

namespace {

const char kGnomeKeyringAppString[] = "chrome";

// Convert the attributes of a given keyring entry into a new PasswordForm.
// Note: does *not* get the actual password, as that is not a key attribute!
// Returns NULL if the attributes are for the wrong application.
scoped_ptr<PasswordForm> FormFromAttributes(GnomeKeyringAttributeList* attrs) {
  // Read the string and int attributes into the appropriate map.
  std::map<std::string, std::string> string_attr_map;
  std::map<std::string, uint32_t> uint_attr_map;
  for (guint i = 0; i < attrs->len; ++i) {
    GnomeKeyringAttribute attr = gnome_keyring_attribute_list_index(attrs, i);
    if (attr.type == GNOME_KEYRING_ATTRIBUTE_TYPE_STRING)
      string_attr_map[attr.name] = attr.value.string;
    else if (attr.type == GNOME_KEYRING_ATTRIBUTE_TYPE_UINT32)
      uint_attr_map[attr.name] = attr.value.integer;
  }
  // Check to make sure this is a password we care about.
  const std::string& app_value = string_attr_map["application"];
  if (!base::StringPiece(app_value).starts_with(kGnomeKeyringAppString))
    return scoped_ptr<PasswordForm>();

  scoped_ptr<PasswordForm> form(new PasswordForm());
  form->origin = GURL(string_attr_map["origin_url"]);
  form->action = GURL(string_attr_map["action_url"]);
  form->username_element = UTF8ToUTF16(string_attr_map["username_element"]);
  form->username_value = UTF8ToUTF16(string_attr_map["username_value"]);
  form->password_element = UTF8ToUTF16(string_attr_map["password_element"]);
  form->submit_element = UTF8ToUTF16(string_attr_map["submit_element"]);
  form->signon_realm = string_attr_map["signon_realm"];
  form->ssl_valid = uint_attr_map["ssl_valid"];
  form->preferred = uint_attr_map["preferred"];
  int64 date_created = 0;
  bool date_ok = base::StringToInt64(string_attr_map["date_created"],
                                     &date_created);
  DCHECK(date_ok);
  form->date_created = base::Time::FromTimeT(date_created);
  form->blacklisted_by_user = uint_attr_map["blacklisted_by_user"];
  form->type = static_cast<PasswordForm::Type>(uint_attr_map["type"]);
  form->times_used = uint_attr_map["times_used"];
  form->scheme = static_cast<PasswordForm::Scheme>(uint_attr_map["scheme"]);
  int64 date_synced = 0;
  base::StringToInt64(string_attr_map["date_synced"], &date_synced);
  form->date_synced = base::Time::FromInternalValue(date_synced);

  return form.Pass();
}

// Parse all the results from the given GList into a PasswordFormList, and free
// the GList. PasswordForms are allocated on the heap, and should be deleted by
// the consumer. If not NULL, |lookup_form| is used to filter out results --
// only credentials with signon realms passing the PSL matching (done by
// |helper|) against |lookup_form->signon_realm| will be kept. PSL matched
// results get their signon_realm, origin, and action rewritten to those of
// |lookup_form_|, with the original signon_realm saved into the result's
// original_signon_realm data member.
void ConvertFormList(GList* found,
                     const PasswordForm* lookup_form,
                     const PSLMatchingHelper& helper,
                     NativeBackendGnome::PasswordFormList* forms) {
  PSLMatchingHelper::PSLDomainMatchMetric psl_domain_match_metric =
      PSLMatchingHelper::PSL_DOMAIN_MATCH_NONE;
  for (GList* element = g_list_first(found); element != NULL;
       element = g_list_next(element)) {
    GnomeKeyringFound* data = static_cast<GnomeKeyringFound*>(element->data);
    GnomeKeyringAttributeList* attrs = data->attributes;

    scoped_ptr<PasswordForm> form(FormFromAttributes(attrs));
    if (form) {
      if (lookup_form && form->signon_realm != lookup_form->signon_realm) {
        // This is not an exact match, we try PSL matching.
        if (lookup_form->scheme != PasswordForm::SCHEME_HTML ||
            form->scheme != PasswordForm::SCHEME_HTML ||
            !(PSLMatchingHelper::IsPublicSuffixDomainMatch(
                lookup_form->signon_realm, form->signon_realm))) {
          continue;
        }
        psl_domain_match_metric = PSLMatchingHelper::PSL_DOMAIN_MATCH_FOUND;
        form->original_signon_realm = form->signon_realm;
        form->signon_realm = lookup_form->signon_realm;
        form->origin = lookup_form->origin;
        form->action = lookup_form->action;
      }
      if (data->secret) {
        form->password_value = UTF8ToUTF16(data->secret);
      } else {
        LOG(WARNING) << "Unable to access password from list element!";
      }
      forms->push_back(form.release());
    } else {
      LOG(WARNING) << "Could not initialize PasswordForm from attributes!";
    }
  }
  if (lookup_form) {
    UMA_HISTOGRAM_ENUMERATION(
        "PasswordManager.PslDomainMatchTriggering",
        helper.IsMatchingEnabled()
            ? psl_domain_match_metric
            : PSLMatchingHelper::PSL_DOMAIN_MATCH_DISABLED,
        PSLMatchingHelper::PSL_DOMAIN_MATCH_COUNT);
  }
}

// Schema is analagous to the fields in PasswordForm.
// TODO(gcasto): Adding 'form_data' would be nice, but we would need to
// serialize in a way that is guaranteed to not have any embedded NULLs. Pickle
// doesn't make this guarantee, so we just don't serialize this field. Since
// it's only used to crowd source data collection it doesn't matter that much
// if it's not available on this platform.
const GnomeKeyringPasswordSchema kGnomeSchema = {
  GNOME_KEYRING_ITEM_GENERIC_SECRET, {
    { "origin_url", GNOME_KEYRING_ATTRIBUTE_TYPE_STRING },
    { "action_url", GNOME_KEYRING_ATTRIBUTE_TYPE_STRING },
    { "username_element", GNOME_KEYRING_ATTRIBUTE_TYPE_STRING },
    { "username_value", GNOME_KEYRING_ATTRIBUTE_TYPE_STRING },
    { "password_element", GNOME_KEYRING_ATTRIBUTE_TYPE_STRING },
    { "submit_element", GNOME_KEYRING_ATTRIBUTE_TYPE_STRING },
    { "signon_realm", GNOME_KEYRING_ATTRIBUTE_TYPE_STRING },
    { "ssl_valid", GNOME_KEYRING_ATTRIBUTE_TYPE_UINT32 },
    { "preferred", GNOME_KEYRING_ATTRIBUTE_TYPE_UINT32 },
    { "date_created", GNOME_KEYRING_ATTRIBUTE_TYPE_STRING },
    { "blacklisted_by_user", GNOME_KEYRING_ATTRIBUTE_TYPE_UINT32 },
    { "scheme", GNOME_KEYRING_ATTRIBUTE_TYPE_UINT32 },
    { "type", GNOME_KEYRING_ATTRIBUTE_TYPE_UINT32 },
    { "times_used", GNOME_KEYRING_ATTRIBUTE_TYPE_UINT32 },
    { "date_synced", GNOME_KEYRING_ATTRIBUTE_TYPE_STRING },
    // This field is always "chrome" so that we can search for it.
    { "application", GNOME_KEYRING_ATTRIBUTE_TYPE_STRING },
    { NULL }
  }
};

// Sadly, PasswordStore goes to great lengths to switch from the originally
// calling thread to the DB thread, and to provide an asynchronous API to
// callers while using a synchronous (virtual) API provided by subclasses like
// PasswordStoreX -- but GNOME Keyring really wants to be on the GLib main
// thread, which is the UI thread to us. So we end up having to switch threads
// again, possibly back to the very same thread (in case the UI thread is the
// caller, e.g. in the password management UI), and *block* the DB thread
// waiting for a response from the UI thread to provide the synchronous API
// PasswordStore expects of us. (It will then in turn switch back to the
// original caller to send the asynchronous reply to the original request.)

// This class represents a call to a GNOME Keyring method. A RunnableMethod
// should be posted to the UI thread to call one of its action methods, and then
// a WaitResult() method should be called to wait for the result. Each instance
// supports only one outstanding method at a time, though multiple instances may
// be used in parallel.
class GKRMethod : public GnomeKeyringLoader {
 public:
  typedef NativeBackendGnome::PasswordFormList PasswordFormList;

  GKRMethod() : event_(false, false), result_(GNOME_KEYRING_RESULT_CANCELLED) {}

  // Action methods. These call gnome_keyring_* functions. Call from UI thread.
  // See GetProfileSpecificAppString() for more information on the app string.
  void AddLogin(const PasswordForm& form, const char* app_string);
  void AddLoginSearch(const PasswordForm& form, const char* app_string);
  void UpdateLoginSearch(const PasswordForm& form, const char* app_string);
  void RemoveLogin(const PasswordForm& form, const char* app_string);
  void GetLogins(const PasswordForm& form, const char* app_string);
  void GetLoginsList(uint32_t blacklisted_by_user, const char* app_string);
  void GetAllLogins(const char* app_string);

  // Use after AddLogin, RemoveLogin.
  GnomeKeyringResult WaitResult();

  // Use after AddLoginSearch, UpdateLoginSearch, GetLogins, GetLoginsList,
  // GetAllLogins.
  GnomeKeyringResult WaitResult(PasswordFormList* forms);

 private:
  struct GnomeKeyringAttributeListFreeDeleter {
    inline void operator()(void* list) const {
      gnome_keyring_attribute_list_free(
          static_cast<GnomeKeyringAttributeList*>(list));
    }
  };

  typedef scoped_ptr<GnomeKeyringAttributeList,
                     GnomeKeyringAttributeListFreeDeleter> ScopedAttributeList;

  // Helper methods to abbreviate Gnome Keyring long API names.
  static void AppendString(ScopedAttributeList* list,
                           const char* name,
                           const char* value);
  static void AppendString(ScopedAttributeList* list,
                           const char* name,
                           const std::string& value);
  static void AppendUint32(ScopedAttributeList* list,
                           const char* name,
                           guint32 value);

  // All these callbacks are called on UI thread.
  static void OnOperationDone(GnomeKeyringResult result, gpointer data);

  static void OnOperationGetList(GnomeKeyringResult result, GList* list,
                                 gpointer data);

  base::WaitableEvent event_;
  GnomeKeyringResult result_;
  NativeBackendGnome::PasswordFormList forms_;
  // If the credential search is specified by a single form and needs to use PSL
  // matching, then the specifying form is stored in |lookup_form_|. If PSL
  // matching is used to find a result, then the results signon realm, origin
  // and action are stored are replaced by those of |lookup_form_|.
  // Additionally, |lookup_form_->signon_realm| is also used to narrow down the
  // found logins to those which indeed PSL-match the look-up. And finally,
  // |lookup_form_| set to NULL means that PSL matching is not required.
  scoped_ptr<PasswordForm> lookup_form_;
  const PSLMatchingHelper helper_;
};

void GKRMethod::AddLogin(const PasswordForm& form, const char* app_string) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  time_t date_created = form.date_created.ToTimeT();
  // If we are asked to save a password with 0 date, use the current time.
  // We don't want to actually save passwords as though on January 1, 1970.
  if (!date_created)
    date_created = time(NULL);
  int64 date_synced = form.date_synced.ToInternalValue();
  gnome_keyring_store_password(
      &kGnomeSchema,
      NULL,  // Default keyring.
      form.origin.spec().c_str(),  // Display name.
      UTF16ToUTF8(form.password_value).c_str(),
      OnOperationDone,
      this,  // data
      NULL,  // destroy_data
      "origin_url", form.origin.spec().c_str(),
      "action_url", form.action.spec().c_str(),
      "username_element", UTF16ToUTF8(form.username_element).c_str(),
      "username_value", UTF16ToUTF8(form.username_value).c_str(),
      "password_element", UTF16ToUTF8(form.password_element).c_str(),
      "submit_element", UTF16ToUTF8(form.submit_element).c_str(),
      "signon_realm", form.signon_realm.c_str(),
      "ssl_valid", form.ssl_valid,
      "preferred", form.preferred,
      "date_created", base::Int64ToString(date_created).c_str(),
      "blacklisted_by_user", form.blacklisted_by_user,
      "type", form.type,
      "times_used", form.times_used,
      "scheme", form.scheme,
      "date_synced", base::Int64ToString(date_synced).c_str(),
      "application", app_string,
      NULL);
}

void GKRMethod::AddLoginSearch(const PasswordForm& form,
                               const char* app_string) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  lookup_form_.reset(NULL);
  // Search GNOME Keyring for matching passwords to update.
  ScopedAttributeList attrs(gnome_keyring_attribute_list_new());
  AppendString(&attrs, "origin_url", form.origin.spec());
  AppendString(&attrs, "username_element", UTF16ToUTF8(form.username_element));
  AppendString(&attrs, "username_value", UTF16ToUTF8(form.username_value));
  AppendString(&attrs, "password_element", UTF16ToUTF8(form.password_element));
  AppendString(&attrs, "submit_element", UTF16ToUTF8(form.submit_element));
  AppendString(&attrs, "signon_realm", form.signon_realm);
  AppendString(&attrs, "application", app_string);
  gnome_keyring_find_items(GNOME_KEYRING_ITEM_GENERIC_SECRET,
                           attrs.get(),
                           OnOperationGetList,
                           /*data=*/this,
                           /*destroy_data=*/NULL);
}

void GKRMethod::UpdateLoginSearch(const PasswordForm& form,
                                  const char* app_string) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  lookup_form_.reset(NULL);
  // Search GNOME Keyring for matching passwords to update.
  ScopedAttributeList attrs(gnome_keyring_attribute_list_new());
  AppendString(&attrs, "origin_url", form.origin.spec());
  AppendString(&attrs, "username_element", UTF16ToUTF8(form.username_element));
  AppendString(&attrs, "username_value", UTF16ToUTF8(form.username_value));
  AppendString(&attrs, "password_element", UTF16ToUTF8(form.password_element));
  AppendString(&attrs, "signon_realm", form.signon_realm);
  AppendString(&attrs, "application", app_string);
  gnome_keyring_find_items(GNOME_KEYRING_ITEM_GENERIC_SECRET,
                           attrs.get(),
                           OnOperationGetList,
                           /*data=*/this,
                           /*destroy_data=*/NULL);
}

void GKRMethod::RemoveLogin(const PasswordForm& form, const char* app_string) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  // We find forms using the same fields as LoginDatabase::RemoveLogin().
  gnome_keyring_delete_password(
      &kGnomeSchema,
      OnOperationDone,
      this,  // data
      NULL,  // destroy_data
      "origin_url", form.origin.spec().c_str(),
      "action_url", form.action.spec().c_str(),
      "username_element", UTF16ToUTF8(form.username_element).c_str(),
      "username_value", UTF16ToUTF8(form.username_value).c_str(),
      "password_element", UTF16ToUTF8(form.password_element).c_str(),
      "submit_element", UTF16ToUTF8(form.submit_element).c_str(),
      "signon_realm", form.signon_realm.c_str(),
      "application", app_string,
      NULL);
}

void GKRMethod::GetLogins(const PasswordForm& form, const char* app_string) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  lookup_form_.reset(new PasswordForm(form));
  // Search GNOME Keyring for matching passwords.
  ScopedAttributeList attrs(gnome_keyring_attribute_list_new());
  if (!helper_.ShouldPSLDomainMatchingApply(
           PSLMatchingHelper::GetRegistryControlledDomain(
               GURL(form.signon_realm)))) {
    AppendString(&attrs, "signon_realm", form.signon_realm);
  }
  AppendString(&attrs, "application", app_string);
  gnome_keyring_find_items(GNOME_KEYRING_ITEM_GENERIC_SECRET,
                           attrs.get(),
                           OnOperationGetList,
                           /*data=*/this,
                           /*destroy_data=*/NULL);
}

void GKRMethod::GetLoginsList(uint32_t blacklisted_by_user,
                              const char* app_string) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  lookup_form_.reset(NULL);
  // Search GNOME Keyring for matching passwords.
  ScopedAttributeList attrs(gnome_keyring_attribute_list_new());
  AppendUint32(&attrs, "blacklisted_by_user", blacklisted_by_user);
  AppendString(&attrs, "application", app_string);
  gnome_keyring_find_items(GNOME_KEYRING_ITEM_GENERIC_SECRET,
                           attrs.get(),
                           OnOperationGetList,
                           /*data=*/this,
                           /*destroy_data=*/NULL);
}

void GKRMethod::GetAllLogins(const char* app_string) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  lookup_form_.reset(NULL);
  // We need to search for something, otherwise we get no results - so
  // we search for the fixed application string.
  ScopedAttributeList attrs(gnome_keyring_attribute_list_new());
  AppendString(&attrs, "application", app_string);
  gnome_keyring_find_items(GNOME_KEYRING_ITEM_GENERIC_SECRET,
                           attrs.get(),
                           OnOperationGetList,
                           /*data=*/this,
                           /*destroy_data=*/NULL);
}

GnomeKeyringResult GKRMethod::WaitResult() {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::DB));
  event_.Wait();
  return result_;
}

GnomeKeyringResult GKRMethod::WaitResult(PasswordFormList* forms) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::DB));
  event_.Wait();
  if (forms->empty()) {
    // Normal case. Avoid extra allocation by swapping.
    forms->swap(forms_);
  } else {
    // Rare case. Append forms_ to *forms.
    forms->insert(forms->end(), forms_.begin(), forms_.end());
    forms_.clear();
  }
  return result_;
}

// static
void GKRMethod::AppendString(GKRMethod::ScopedAttributeList* list,
                             const char* name,
                             const char* value) {
  gnome_keyring_attribute_list_append_string(list->get(), name, value);
}

// static
void GKRMethod::AppendString(GKRMethod::ScopedAttributeList* list,
                             const char* name,
                             const std::string& value) {
  AppendString(list, name, value.c_str());
}

// static
void GKRMethod::AppendUint32(GKRMethod::ScopedAttributeList* list,
                             const char* name,
                             guint32 value) {
  gnome_keyring_attribute_list_append_uint32(list->get(), name, value);
}

// static
void GKRMethod::OnOperationDone(GnomeKeyringResult result, gpointer data) {
  GKRMethod* method = static_cast<GKRMethod*>(data);
  method->result_ = result;
  method->event_.Signal();
}

// static
void GKRMethod::OnOperationGetList(GnomeKeyringResult result, GList* list,
                                   gpointer data) {
  GKRMethod* method = static_cast<GKRMethod*>(data);
  method->result_ = result;
  method->forms_.clear();
  // |list| will be freed after this callback returns, so convert it now.
  ConvertFormList(
      list, method->lookup_form_.get(), method->helper_, &method->forms_);
  method->lookup_form_.reset(NULL);
  method->event_.Signal();
}

}  // namespace

NativeBackendGnome::NativeBackendGnome(LocalProfileId id)
    : profile_id_(id) {
  app_string_ = GetProfileSpecificAppString();
}

NativeBackendGnome::~NativeBackendGnome() {
}

bool NativeBackendGnome::Init() {
  return LoadGnomeKeyring() && gnome_keyring_is_available();
}

bool NativeBackendGnome::RawAddLogin(const PasswordForm& form) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::DB));
  GKRMethod method;
  BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
                          base::Bind(&GKRMethod::AddLogin,
                                     base::Unretained(&method),
                                     form, app_string_.c_str()));
  GnomeKeyringResult result = method.WaitResult();
  if (result != GNOME_KEYRING_RESULT_OK) {
    LOG(ERROR) << "Keyring save failed: "
               << gnome_keyring_result_to_message(result);
    return false;
  }
  return true;
}

password_manager::PasswordStoreChangeList NativeBackendGnome::AddLogin(
    const PasswordForm& form) {
  // Based on LoginDatabase::AddLogin(), we search for an existing match based
  // on origin_url, username_element, username_value, password_element, submit
  // element, and signon_realm first, remove that, and then add the new entry.
  // We'd add the new one first, and then delete the original, but then the
  // delete might actually delete the newly-added entry!
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::DB));
  GKRMethod method;
  BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
                          base::Bind(&GKRMethod::AddLoginSearch,
                                     base::Unretained(&method),
                                     form, app_string_.c_str()));
  ScopedVector<autofill::PasswordForm> forms;
  GnomeKeyringResult result = method.WaitResult(&forms.get());
  if (result != GNOME_KEYRING_RESULT_OK &&
      result != GNOME_KEYRING_RESULT_NO_MATCH) {
    LOG(ERROR) << "Keyring find failed: "
               << gnome_keyring_result_to_message(result);
    return password_manager::PasswordStoreChangeList();
  }
  password_manager::PasswordStoreChangeList changes;
  if (forms.size() > 0) {
    if (forms.size() > 1) {
      LOG(WARNING) << "Adding login when there are " << forms.size()
                   << " matching logins already! Will replace only the first.";
    }

    if (RemoveLogin(*forms[0])) {
      changes.push_back(password_manager::PasswordStoreChange(
          password_manager::PasswordStoreChange::REMOVE, *forms[0]));
    }
  }
  if (RawAddLogin(form)) {
    changes.push_back(password_manager::PasswordStoreChange(
        password_manager::PasswordStoreChange::ADD, form));
  }
  return changes;
}

bool NativeBackendGnome::UpdateLogin(
    const PasswordForm& form,
    password_manager::PasswordStoreChangeList* changes) {
  // Based on LoginDatabase::UpdateLogin(), we search for forms to update by
  // origin_url, username_element, username_value, password_element, and
  // signon_realm. We then compare the result to the updated form. If they
  // differ in any of the mutable fields, then we remove the original, and
  // then add the new entry. We'd add the new one first, and then delete the
  // original, but then the delete might actually delete the newly-added entry!
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::DB));
  DCHECK(changes);
  changes->clear();
  GKRMethod method;
  BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
                          base::Bind(&GKRMethod::UpdateLoginSearch,
                                     base::Unretained(&method),
                                     form, app_string_.c_str()));
  ScopedVector<autofill::PasswordForm> forms;
  GnomeKeyringResult result = method.WaitResult(&forms.get());
  if (result != GNOME_KEYRING_RESULT_OK) {
    LOG(ERROR) << "Keyring find failed: "
               << gnome_keyring_result_to_message(result);
    return false;
  }

  bool removed = false;
  for (size_t i = 0; i < forms.size(); ++i) {
    if (*forms[i] != form) {
      RemoveLogin(*forms[i]);
      removed = true;
    }
  }
  if (!removed)
    return true;

  if (RawAddLogin(form)) {
    password_manager::PasswordStoreChange change(
        password_manager::PasswordStoreChange::UPDATE, form);
    changes->push_back(change);
    return true;
  }
  return false;
}

bool NativeBackendGnome::RemoveLogin(const PasswordForm& form) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::DB));
  GKRMethod method;
  BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
                          base::Bind(&GKRMethod::RemoveLogin,
                                     base::Unretained(&method),
                                     form, app_string_.c_str()));
  GnomeKeyringResult result = method.WaitResult();
  if (result != GNOME_KEYRING_RESULT_OK) {
    // Warning, not error, because this can sometimes happen due to the user
    // racing with the daemon to delete the password a second time.
    LOG(WARNING) << "Keyring delete failed: "
                 << gnome_keyring_result_to_message(result);
    return false;
  }
  return true;
}

bool NativeBackendGnome::RemoveLoginsCreatedBetween(
    base::Time delete_begin,
    base::Time delete_end,
    password_manager::PasswordStoreChangeList* changes) {
  return RemoveLoginsBetween(
      delete_begin, delete_end, CREATION_TIMESTAMP, changes);
}

bool NativeBackendGnome::RemoveLoginsSyncedBetween(
    base::Time delete_begin,
    base::Time delete_end,
    password_manager::PasswordStoreChangeList* changes) {
  return RemoveLoginsBetween(delete_begin, delete_end, SYNC_TIMESTAMP, changes);
}

bool NativeBackendGnome::GetLogins(const PasswordForm& form,
                                   PasswordFormList* forms) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::DB));
  GKRMethod method;
  BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
                          base::Bind(&GKRMethod::GetLogins,
                                     base::Unretained(&method),
                                     form, app_string_.c_str()));
  GnomeKeyringResult result = method.WaitResult(forms);
  if (result == GNOME_KEYRING_RESULT_NO_MATCH)
    return true;
  if (result != GNOME_KEYRING_RESULT_OK) {
    LOG(ERROR) << "Keyring find failed: "
               << gnome_keyring_result_to_message(result);
    return false;
  }
  return true;
}

bool NativeBackendGnome::GetAutofillableLogins(PasswordFormList* forms) {
  return GetLoginsList(forms, true);
}

bool NativeBackendGnome::GetBlacklistLogins(PasswordFormList* forms) {
  return GetLoginsList(forms, false);
}

bool NativeBackendGnome::GetLoginsList(PasswordFormList* forms,
                                       bool autofillable) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::DB));

  uint32_t blacklisted_by_user = !autofillable;

  GKRMethod method;
  BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
                          base::Bind(&GKRMethod::GetLoginsList,
                                     base::Unretained(&method),
                                     blacklisted_by_user, app_string_.c_str()));
  GnomeKeyringResult result = method.WaitResult(forms);
  if (result == GNOME_KEYRING_RESULT_NO_MATCH)
    return true;
  if (result != GNOME_KEYRING_RESULT_OK) {
    LOG(ERROR) << "Keyring find failed: "
               << gnome_keyring_result_to_message(result);
    return false;
  }
  return true;
}

bool NativeBackendGnome::GetAllLogins(PasswordFormList* forms) {
  GKRMethod method;
  BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
                          base::Bind(&GKRMethod::GetAllLogins,
                                     base::Unretained(&method),
                                     app_string_.c_str()));
  GnomeKeyringResult result = method.WaitResult(forms);
  if (result == GNOME_KEYRING_RESULT_NO_MATCH)
    return true;
  if (result != GNOME_KEYRING_RESULT_OK) {
    LOG(ERROR) << "Keyring find failed: "
               << gnome_keyring_result_to_message(result);
    return false;
  }
  return true;
}

bool NativeBackendGnome::GetLoginsBetween(base::Time get_begin,
                                          base::Time get_end,
                                          TimestampToCompare date_to_compare,
                                          PasswordFormList* forms) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::DB));
  // We could walk the list and add items as we find them, but it is much
  // easier to build the list and then filter the results.
  PasswordFormList all_forms;
  if (!GetAllLogins(&all_forms))
    return false;

  base::Time autofill::PasswordForm::*date_member =
      date_to_compare == CREATION_TIMESTAMP
          ? &autofill::PasswordForm::date_created
          : &autofill::PasswordForm::date_synced;
  for (size_t i = 0; i < all_forms.size(); ++i) {
    if (get_begin <= all_forms[i]->*date_member &&
        (get_end.is_null() || all_forms[i]->*date_member < get_end)) {
      forms->push_back(all_forms[i]);
    } else {
      delete all_forms[i];
    }
  }

  return true;
}

bool NativeBackendGnome::RemoveLoginsBetween(
    base::Time get_begin,
    base::Time get_end,
    TimestampToCompare date_to_compare,
    password_manager::PasswordStoreChangeList* changes) {
  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::DB));
  DCHECK(changes);
  changes->clear();
  // We could walk the list and delete items as we find them, but it is much
  // easier to build the list and use RemoveLogin() to delete them.
  ScopedVector<autofill::PasswordForm> forms;
  if (!GetLoginsBetween(get_begin, get_end, date_to_compare, &forms.get()))
    return false;

  bool ok = true;
  for (size_t i = 0; i < forms.size(); ++i) {
    if (RemoveLogin(*forms[i])) {
      changes->push_back(password_manager::PasswordStoreChange(
          password_manager::PasswordStoreChange::REMOVE, *forms[i]));
    } else {
      ok = false;
    }
  }
  return ok;
}

std::string NativeBackendGnome::GetProfileSpecificAppString() const {
  // Originally, the application string was always just "chrome" and used only
  // so that we had *something* to search for since GNOME Keyring won't search
  // for nothing. Now we use it to distinguish passwords for different profiles.
  return base::StringPrintf("%s-%d", kGnomeKeyringAppString, profile_id_);
}