Add password change feature.

4 files changed, 246 insertions, 58 deletions

diff --git a/src/leap/bitmask/crypto/srpauth.py b/src/leap/bitmask/crypto/srpauth.py
index 7b91205f..41ce130a 100644
--- a/src/leap/bitmask/crypto/srpauth.py
+++ b/src/leap/bitmask/crypto/srpauth.py
@@ -134,6 +134,8 @@ class SRPAuth(QtCore.QObject):
         A_KEY = "A"
         CLIENT_AUTH_KEY = "client_auth"
         SESSION_ID_KEY = "_session_id"
+        USER_VERIFIER_KEY = 'user[password_verifier]'
+        USER_SALT_KEY = 'user[password_salt]'
 
         def __init__(self, provider_config):
             """
@@ -169,6 +171,10 @@ class SRPAuth(QtCore.QObject):
             self._srp_user = None
             self._srp_a = None
 
+            # User credentials stored for password changing checks
+            self._username = None
+            self._password = None
+
         def _safe_unhexlify(self, val):
             """
             Rounds the val to a multiple of 2 and returns the
@@ -438,6 +444,51 @@ class SRPAuth(QtCore.QObject):
         def _threader(self, cb, res, *args, **kwargs):
             return threads.deferToThread(cb, res, *args, **kwargs)
 
+        def change_password(self, current_password, new_password):
+            """
+            Changes the password for the currently logged user if the current
+            password match.
+            It requires to be authenticated.
+
+            Might raise:
+                SRPAuthBadPassword
+                requests.exceptions.HTTPError
+
+            :param current_password: the current password for the logged user.
+            :type current_password: str
+            :param new_password: the new password for the user
+            :type new_password: str
+            """
+            leap_assert(self.get_uid() is not None)
+
+            if current_password != self._password:
+                raise SRPAuthBadPassword
+
+            url = "%s/%s/users/%s.json" % (
+                self._provider_config.get_api_uri(),
+                self._provider_config.get_api_version(),
+                self.get_uid())
+
+            salt, verifier = self._srp.create_salted_verification_key(
+                self._username, new_password, self._hashfun, self._ng)
+
+            cookies = {self.SESSION_ID_KEY: self.get_session_id()}
+            user_data = {
+                self.USER_VERIFIER_KEY: binascii.hexlify(verifier),
+                self.USER_SALT_KEY: binascii.hexlify(salt)
+            }
+
+            change_password = self._session.put(
+                url, data=user_data,
+                verify=self._provider_config.get_ca_cert_path(),
+                cookies=cookies,
+                timeout=REQUEST_TIMEOUT)
+
+            # In case of non 2xx it raises HTTPError
+            change_password.raise_for_status()
+
+            self._password = new_password
+
         def authenticate(self, username, password):
             """
             Executes the whole authentication process for a user
@@ -454,6 +505,10 @@ class SRPAuth(QtCore.QObject):
             """
             leap_assert(self.get_session_id() is None, "Already logged in")
 
+            # User credentials stored for password changing checks
+            self._username = username.lower()
+            self._password = password
+
             d = threads.deferToThread(self._authentication_preprocessing,
                                       username=username,
                                       password=password)
@@ -565,6 +620,33 @@ class SRPAuth(QtCore.QObject):
         d.addErrback(self._errback)
         return d
 
+    def change_password(self, current_password, new_password):
+        """
+        Changes the user's password.
+
+        :param current_password: the current password of the user.
+        :type current_password: str
+        :param new_password: the new password for the user.
+        :type new_password: str
+
+        :returns: a defer to interact with.
+        :rtype: twisted.internet.defer.Deferred
+        """
+        d = threads.deferToThread(
+            self.__instance.change_password, current_password, new_password)
+        return d
+
+    def get_username(self):
+        """
+        Returns the username of the currently authenticated user or None if
+        no user is logged.
+
+        :rtype: str or None
+        """
+        if self.get_uid() is None:
+            return None
+        return self.__instance._username
+
     def _gui_notify(self, _):
         """
         Callback that notifies the UI with the proper signal.
diff --git a/src/leap/bitmask/gui/mainwindow.py b/src/leap/bitmask/gui/mainwindow.py
index 5447d993..c832887a 100644
--- a/src/leap/bitmask/gui/mainwindow.py
+++ b/src/leap/bitmask/gui/mainwindow.py
@@ -288,6 +288,10 @@ class MainWindow(QtGui.QMainWindow):
 
         ################################# end Qt Signals connection ########
 
+        # Enable the password change when soledad is ready
+        self.soledad_ready.connect(
+            partial(self.ui.btnPreferences.setEnabled, True))
+
         init_platform()
 
         self._wizard = None
@@ -415,11 +419,7 @@ class MainWindow(QtGui.QMainWindow):
 
         Displays the preferences window.
         """
-        preferences = self._preferences_window
-        if preferences is None:
-            preferences = PreferencesWindow(self, self._srp_auth)
-
-        preferences.show()
+        PreferencesWindow(self, self._srp_auth, self._soledad).show()
 
     def _uncheck_logger_button(self):
         """
@@ -943,7 +943,6 @@ class MainWindow(QtGui.QMainWindow):
             # panel
             QtCore.QTimer.singleShot(1000, self._switch_to_status)
             self._login_defer = None
-            self.ui.btnPreferences.setEnabled(True)
         else:
             self._login_widget.set_enabled(True)
 
diff --git a/src/leap/bitmask/gui/preferenceswindow.py b/src/leap/bitmask/gui/preferenceswindow.py
index 5f8dd5cc..67448768 100644
--- a/src/leap/bitmask/gui/preferenceswindow.py
+++ b/src/leap/bitmask/gui/preferenceswindow.py
@@ -16,13 +16,15 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 """
-Preferences log window
+Preferences window
 """
 import logging
 
+from functools import partial
 from PySide import QtGui
 
 from leap.bitmask.gui.ui_preferences import Ui_Preferences
+from leap.soledad.client import NoStorageSecret
 from leap.bitmask.crypto.srpauth import SRPAuthBadPassword
 
 logger = logging.getLogger(__name__)
@@ -32,9 +34,163 @@ class PreferencesWindow(QtGui.QDialog):
     """
     Window that displays the preferences.
     """
-    def __init__(self, parent):
+
+    WEAK_PASSWORDS = ("123456", "qweasd", "qwerty", "password")
+
+    def __init__(self, parent, srp_auth, soledad):
+        """
+        :param parent: parent object of the PreferencesWindow.
+        :parent type: QWidget
+        :param srp_auth: SRPAuth object configured in the main app.
+        :type srp_auth: SRPAuth
+        :param soledad: Soledad object configured in the main app.
+        :type soledad: Soledad
+        """
         QtGui.QDialog.__init__(self, parent)
 
+        self._srp_auth = srp_auth
+        self._soledad = soledad
+
         # Load UI
         self.ui = Ui_Preferences()
         self.ui.setupUi(self)
+        self.ui.lblPasswordChangeStatus.setVisible(False)
+
+        # Connections
+        self.ui.pbChangePassword.clicked.connect(self._change_password)
+
+    def _basic_password_checks(self, username, password, password2):
+        """
+        Performs basic password checks to avoid really easy passwords.
+
+        :param username: username provided at the registrarion form
+        :type username: str
+        :param password: password from the registration form
+        :type password: str
+        :param password2: second password from the registration form
+        :type password: str
+
+        :returns: True and empty message if all the checks pass,
+                  False and an error message otherwise
+        :rtype: tuple(bool, str)
+        """
+        message = None
+
+        if message is None and password != password2:
+            message = self.tr("Passwords don't match")
+
+        if message is None and len(password) < 6:
+            message = self.tr("Password too short")
+
+        if message is None and password in self.WEAK_PASSWORDS:
+            message = self.tr("Password too easy")
+
+        if message is None and username == password:
+            message = self.tr("Password equal to username")
+
+        return message is None, message
+
+    def _set_password_change_status(self, status, error=False, success=False):
+        """
+        Sets the status label for the password change.
+
+        :param status: status message to display, can be HTML
+        :type status: str
+        """
+        if error:
+            status = "<font color='red'><b>%s</b></font>" % (status,)
+        elif success:
+            status = "<font color='green'><b>%s</b></font>" % (status,)
+
+        self.ui.lblPasswordChangeStatus.setVisible(True)
+        self.ui.lblPasswordChangeStatus.setText(status)
+
+    def _set_changing_password(self, disable):
+        """
+        Enables or disables the widgets in the password change group box.
+
+        :param disable: True if the widgets should be disabled and
+                        it displays the status label that shows that is
+                        changing the password.
+                        False if they should be enabled.
+        :type disable: bool
+        """
+        if disable:
+            self._set_password_change_disable(self.tr("Changing password..."))
+
+        self.ui.leCurrentPassword.setEnabled(not disable)
+        self.ui.leNewPassword.setEnabled(not disable)
+        self.ui.leNewPassword2.setEnabled(not disable)
+        self.ui.pbChangePassword.setEnabled(not disable)
+
+    def _change_password(self):
+        """
+        Changes the user's password if the inputboxes are correctly filled.
+        """
+        username = self._srp_auth.get_username()
+        current_password = self.ui.leCurrentPassword.text()
+        new_password = self.ui.leNewPassword.text()
+        new_password2 = self.ui.leNewPassword2.text()
+
+        ok, msg = self._basic_password_checks(
+            username, new_password, new_password2)
+
+        if not ok:
+            self._set_changing_password(False)
+            self._set_password_change_status(msg, error=True)
+            self.ui.leNewPassword.setFocus()
+            return
+
+        self._set_changing_password(True)
+        d = self._srp_auth.change_password(current_password, new_password)
+        d.addCallback(partial(self._change_password_success, new_password))
+        d.addErrback(self._change_password_problem)
+
+    def _change_password_success(self, new_password, _):
+        """
+        Callback used to display a successfully performed action.
+
+        :param new_password: the new password for the user.
+        :type new_password: str.
+        :param _: the returned data from self._srp_auth.change_password
+                  Ignored
+        """
+        logger.debug("SRP password changed successfully.")
+        try:
+            self._soledad.change_passphrase(str(new_password))
+            logger.debug("Soledad password changed successfully.")
+        except NoStorageSecret:
+            logger.debug(
+                "No storage secret for password change in Soledad.")
+
+        self._set_password_change_status(
+            self.tr("Password changed successfully."), success=True)
+        self._clear_inputs()
+        self._set_changing_password(False)
+
+    def _change_password_problem(self, failure):
+        """
+        Errback called if there was a problem with the deferred.
+        Also is used to display an error message.
+
+        :param failure: the cause of the method failed.
+        :type failure: twisted.python.Failure
+        """
+        logger.error("Error changing password: %s", (failure, ))
+        problem = self.tr("There was a problem changing the password.")
+
+        if failure.check(SRPAuthBadPassword):
+            problem = self.tr("You did not enter a correct current password.")
+
+        self._set_password_change_status(problem, error=True)
+
+        self._set_changing_password(False)
+        failure.trap(Exception)
+
+    def _clear_inputs(self):
+        """
+        Clear the contents of the inputs.
+        """
+        self.ui.leCurrentPassword.setText("")
+        self.ui.leNewPassword.setText("")
+        self.ui.leNewPassword2.setText("")
diff --git a/src/leap/bitmask/gui/ui/preferences.ui b/src/leap/bitmask/gui/ui/preferences.ui
index ffca381e..8c63ccad 100644
--- a/src/leap/bitmask/gui/ui/preferences.ui
+++ b/src/leap/bitmask/gui/ui/preferences.ui
@@ -166,54 +166,5 @@
  <resources>
   <include location="../../../../../data/resources/mainwindow.qrc"/>
  </resources>
- <connections>
-  <connection>
-   <sender>leCurrentPassword</sender>
-   <signal>returnPressed()</signal>
-   <receiver>leNewPassword</receiver>
-   <slot>setFocus()</slot>
-   <hints>
-    <hint type="sourcelabel">
-     <x>273</x>
-     <y>113</y>
-    </hint>
-    <hint type="destinationlabel">
-     <x>272</x>
-     <y>135</y>
-    </hint>
-   </hints>
-  </connection>
-  <connection>
-   <sender>leNewPassword</sender>
-   <signal>returnPressed()</signal>
-   <receiver>leNewPassword2</receiver>
-   <slot>setFocus()</slot>
-   <hints>
-    <hint type="sourcelabel">
-     <x>349</x>
-     <y>139</y>
-    </hint>
-    <hint type="destinationlabel">
-     <x>351</x>
-     <y>163</y>
-    </hint>
-   </hints>
-  </connection>
-  <connection>
-   <sender>leNewPassword2</sender>
-   <signal>returnPressed()</signal>
-   <receiver>pbChangePassword</receiver>
-   <slot>setFocus()</slot>
-   <hints>
-    <hint type="sourcelabel">
-     <x>178</x>
-     <y>169</y>
-    </hint>
-    <hint type="destinationlabel">
-     <x>178</x>
-     <y>198</y>
-    </hint>
-   </hints>
-  </connection>
- </connections>
+ <connections/>
 </ui>