[nanny: 4/15] Add check_policy at server side

[Roberto Majadas <telemaco src gnome org>]

commit b12da15c09bb2666bbd4f1c03c5848ac052d1e37
Author: Roberto Majadas <roberto majadas openshine com>
Date:   Sat Mar 13 16:48:19 2010 +0100

    Add check_policy at server side

 daemon/src/NannyDBus.py |  125 +++++++++++++++++++++++++++++++++++++---------
 1 files changed, 100 insertions(+), 25 deletions(-)
---
diff --git a/daemon/src/NannyDBus.py b/daemon/src/NannyDBus.py
index dd855e9..8bee8fc 100644
--- a/daemon/src/NannyDBus.py
+++ b/daemon/src/NannyDBus.py
@@ -29,6 +29,9 @@ import dbus
 import dbus.service
 import dbus.mainloop.glib
 
+class PermissionDeniedByPolicy(dbus.DBusException):
+    _dbus_error_name = 'org.gnome.nanny.PermissionDeniedByPolicy'
+
 class NannyDBus(dbus.service.Object):
     def __init__ (self, quarterback):
         
@@ -41,6 +44,55 @@ class NannyDBus(dbus.service.Object):
 
         self.quarterback.connect('block-status', self.__UserNotification_cb)
         self.quarterback.connect('update-users-info', self.__UpdateUsersInfo_cb)
+        
+        self.dbus_info = None
+        self.polkit = None
+
+    # Taken from Jockey 0.5.8.
+    def _check_polkit_privilege(self, sender, conn, privilege):
+        '''Verify that sender has a given PolicyKit privilege.
+
+        sender is the sender's (private) D-BUS name, such as ":1:42"
+        (sender_keyword in @dbus.service.methods). conn is
+        the dbus.Connection object (connection_keyword in
+        @dbus.service.methods). privilege is the PolicyKit privilege string.
+
+        This method returns if the caller is privileged, and otherwise throws a
+        PermissionDeniedByPolicy exception.
+        '''
+        if sender is None and conn is None:
+            # called locally, not through D-BUS
+            return
+
+        # get peer PID
+        if self.dbus_info is None:
+            self.dbus_info = dbus.Interface(conn.get_object('org.freedesktop.DBus',
+                '/org/freedesktop/DBus/Bus', False), 'org.freedesktop.DBus')
+        pid = self.dbus_info.GetConnectionUnixProcessID(sender)
+
+        # query PolicyKit
+        if self.polkit is None:
+            self.polkit = dbus.Interface(dbus.SystemBus().get_object(
+                'org.freedesktop.PolicyKit1',
+                '/org/freedesktop/PolicyKit1/Authority', False),
+                'org.freedesktop.PolicyKit1.Authority')
+        try:
+            # we don't need is_challenge return here, since we call with AllowUserInteraction
+            (is_auth, _, details) = self.polkit.CheckAuthorization(
+                    ('unix-process', {'pid': dbus.UInt32(pid, variant_level=1),
+                        'start-time': dbus.UInt64(0, variant_level=1)}),
+                    privilege, {'': ''}, dbus.UInt32(1), '', timeout=600)
+        except dbus.DBusException, e:
+            if e._dbus_error_name == 'org.freedesktop.DBus.Error.ServiceUnknown':
+                # polkitd timed out, connect again
+                self.polkit = None
+                return self._check_polkit_privilege(sender, conn, privilege)
+            else:
+                raise
+
+        if not is_auth:
+            print '_check_polkit_privilege: sender %s on connection %s pid %i is not authorized for %s: %s' % (sender, conn, pid, privilege, str(details))
+            raise PermissionDeniedByPolicy(privilege)
 
     # org.gnome.Nanny
     # --------------------------------------------------------------
@@ -51,12 +103,13 @@ class NannyDBus(dbus.service.Object):
         return self.quarterback.usersmanager.get_users()
 
     @dbus.service.method("org.gnome.Nanny",
-                         in_signature='sia{sa(ss)}', out_signature='b')
-    def SetBlocks(self, user_id, app_id, blocks):
+                         in_signature='sia{sa(ss)}', out_signature='b',
+                         sender_keyword='sender', connection_keyword='conn')
+    def SetBlocks(self, user_id, app_id, blocks, sender=None, conn=None):
+        self._check_polkit_privilege(sender, conn, 'org.gnome.nanny.admin')
         self.quarterback.set_blocks(str(user_id), int(app_id), blocks)
         return True
 
-
     @dbus.service.method("org.gnome.Nanny",
                          in_signature='si', out_signature='a{sa(ss)}')
     def GetBlocks(self, user_id, app_id) :
@@ -64,8 +117,10 @@ class NannyDBus(dbus.service.Object):
         return ret
 
     @dbus.service.method("org.gnome.Nanny",
-                         in_signature='bs', out_signature='')
-    def SetActiveWCF(self, active, uid):
+                         in_signature='bs', out_signature='',
+                         sender_keyword='sender', connection_keyword='conn')
+    def SetActiveWCF(self, active, uid, sender=None, conn=None):
+        self._check_polkit_privilege(sender, conn, 'org.gnome.nanny.admin')
         self.quarterback.set_wcf(bool(active), str(uid))
 
     @dbus.service.method("org.gnome.Nanny",
@@ -74,8 +129,10 @@ class NannyDBus(dbus.service.Object):
         return self.quarterback.list_wcf_uids()
 
     @dbus.service.method("org.gnome.Nanny",
-                         in_signature='sii', out_signature='')
-    def SetMaxUseTime(self, user_id, app_id, mins):
+                         in_signature='sii', out_signature='',
+                         sender_keyword='sender', connection_keyword='conn')
+    def SetMaxUseTime(self, user_id, app_id, mins, sender=None, conn=None):
+        self._check_polkit_privilege(sender, conn, 'org.gnome.nanny.admin')
         self.quarterback.set_max_use_time(str(user_id), int(app_id), int(mins))
 
     @dbus.service.method("org.gnome.Nanny",
@@ -107,8 +164,10 @@ class NannyDBus(dbus.service.Object):
     # --------------------------------------------------------------
 
     @dbus.service.method("org.gnome.Nanny.WebDatabase",
-                         in_signature='sbsss', out_signature='b')
-    def AddCustomFilter(self, uid, is_black, name, description, regex):
+                         in_signature='sbsss', out_signature='b',
+                         sender_keyword='sender', connection_keyword='conn')
+    def AddCustomFilter(self, uid, is_black, name, description, regex, sender=None, conn=None):
+        self._check_polkit_privilege(sender, conn, 'org.gnome.nanny.admin')
         return self.quarterback.filter_manager.add_custom_filter(str(uid), bool(is_black), unicode(name),
                                                                           unicode(description), unicode(regex))
 
@@ -118,32 +177,42 @@ class NannyDBus(dbus.service.Object):
         return self.quarterback.filter_manager.list_custom_filters(int(uid))
 
     @dbus.service.method("org.gnome.Nanny.WebDatabase",
-                         in_signature='i', out_signature='b')
-    def RemoveCustomFilter(self, list_id):
+                         in_signature='i', out_signature='b',
+                         sender_keyword='sender', connection_keyword='conn')
+    def RemoveCustomFilter(self, list_id, sender=None, conn=None):
+        self._check_polkit_privilege(sender, conn, 'org.gnome.nanny.admin')
         return self.quarterback.filter_manager.remove_custom_filter(int(list_id))
 
     
     @dbus.service.method("org.gnome.Nanny.WebDatabase",
-                         in_signature='isss', out_signature='b')
-    def UpdateCustomFilter(self, list_id, name, description, regex):
+                         in_signature='isss', out_signature='b',
+                         sender_keyword='sender', connection_keyword='conn')
+    def UpdateCustomFilter(self, list_id, name, description, regex, sender=None, conn=None):
+        self._check_polkit_privilege(sender, conn, 'org.gnome.nanny.admin')
         return self.quarterback.filter_manager.update_custom_filter(int(list_id),
                                                                     unicode(name),
                                                                     unicode(description),
                                                                     unicode(regex))
 
     @dbus.service.method("org.gnome.Nanny.WebDatabase",
-                         in_signature='s', out_signature='b')
-    def AddPkgFilter(self, path):
+                         in_signature='s', out_signature='b',
+                         sender_keyword='sender', connection_keyword='conn')
+    def AddPkgFilter(self, path, sender=None, conn=None):
+        self._check_polkit_privilege(sender, conn, 'org.gnome.nanny.admin')
         return self.quarterback.filter_manager.add_pkg_filter(str(path))
 
     @dbus.service.method("org.gnome.Nanny.WebDatabase",
-                         in_signature='s', out_signature='b')
-    def RemovePkgFilter(self, pkg_id):
+                         in_signature='s', out_signature='b',
+                         sender_keyword='sender', connection_keyword='conn')
+    def RemovePkgFilter(self, pkg_id, sender=None, conn=None):
+        self._check_polkit_privilege(sender, conn, 'org.gnome.nanny.admin')
         return self.quarterback.filter_manager.remove_pkg_filter(str(pkg_id))
 
     @dbus.service.method("org.gnome.Nanny.WebDatabase",
-                         in_signature='ss', out_signature='b')
-    def UpdatePkgFilter(self, pkg_id, new_db_path):
+                         in_signature='ss', out_signature='b',
+                         sender_keyword='sender', connection_keyword='conn')
+    def UpdatePkgFilter(self, pkg_id, new_db_path, sender=None, conn=None):
+        self._check_polkit_privilege(sender, conn, 'org.gnome.nanny.admin')
         return self.quarterback.filter_manager.update_pkg_filter(str(pkg_id), str (new_db_path))
     
     @dbus.service.method("org.gnome.Nanny.WebDatabase",
@@ -157,8 +226,10 @@ class NannyDBus(dbus.service.Object):
         return self.quarterback.filter_manager.get_pkg_filter_metadata(str(pkg_id))
 
     @dbus.service.method("org.gnome.Nanny.WebDatabase",
-                         in_signature='sss', out_signature='b')
-    def SetPkgFilterMetadata(self, pkg_id, name, description):
+                         in_signature='sss', out_signature='b',
+                         sender_keyword='sender', connection_keyword='conn')
+    def SetPkgFilterMetadata(self, pkg_id, name, description, sender=None, conn=None):
+        self._check_polkit_privilege(sender, conn, 'org.gnome.nanny.admin')
         return self.quarterback.filter_manager.set_pkg_filter_metadata(str(pkg_id), unicode(name), unicode(description))
 
     @dbus.service.method("org.gnome.Nanny.WebDatabase",
@@ -169,8 +240,10 @@ class NannyDBus(dbus.service.Object):
                                                                               )
 
     @dbus.service.method("org.gnome.Nanny.WebDatabase",
-                         in_signature='ssas', out_signature='b')
-    def SetPkgFilterUserCategories(self, pkg_id, uid, list_categories):
+                         in_signature='ssas', out_signature='b',
+                         sender_keyword='sender', connection_keyword='conn')
+    def SetPkgFilterUserCategories(self, pkg_id, uid, list_categories, sender=None, conn=None):
+        self._check_polkit_privilege(sender, conn, 'org.gnome.nanny.admin')
         list_c = []
         for x in list_categories :
             list_c.append(unicode(x))
@@ -185,8 +258,10 @@ class NannyDBus(dbus.service.Object):
         return self.quarterback.filter_manager.check_domain(uid, domain)
                                                                               
     @dbus.service.method("org.gnome.Nanny.WebDatabase",
-                         in_signature='ssss', out_signature='b')
-    def AddDansGuardianList(self, uid, name, description, list_url):
+                         in_signature='ssss', out_signature='b',
+                         sender_keyword='sender', connection_keyword='conn')
+    def AddDansGuardianList(self, uid, name, description, list_url, sender=None, conn=None):
+        self._check_polkit_privilege(sender, conn, 'org.gnome.nanny.admin')
         return self.quarterback.webcontent_filter.webdb.add_dans_guardian_list(str(uid),
                                                                                unicode(name),
                                                                                unicode(description),