swfdec/swfdec_sandbox.c

   1 /* Swfdec
   2  * Copyright (C) 2007 Benjamin Otte <otte@gnome.org>
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor,
  17  * Boston, MA  02110-1301  USA
  18  */
  19
  20 #ifdef HAVE_CONFIG_H
  21 #include "config.h"
  22 #endif
  23
  24 #include "swfdec_sandbox.h"
  25 #include "swfdec_as_internal.h"
  26 #include "swfdec_debug.h"
  27 #include "swfdec_initialize.h"
  28 #include "swfdec_internal.h"
  29 #include "swfdec_player_internal.h"
  30
  31 /*** GTK-DOC ***/
  32
  33 /**
  34  * SECTION:SwfdecSandbox
  35  * @title: SwfdecSandbox
  36  * @short_description: global object used for security
  37  *
  38  * The SwfdecSandbox object is a garbage-collected script object that does two
  39  * things. The simple thing is its use as the global object while code is
  40  * executed in a #SwfdecPlayer. So you can always assume that the global object
  41  * is a #SwfdecSandbox. The second task it fulfills is acting as the security
  42  * mechanism used by native functions to determine if a given action should be
  43  * allowed or not. This is easy, because script functions can always refer to
  44  * it as the global object.
  45  */
  46
  47 G_DEFINE_TYPE (SwfdecSandbox, swfdec_sandbox, SWFDEC_TYPE_AS_OBJECT)
  48
  49 static void
  50 swfdec_sandbox_mark (SwfdecGcObject *object)
  51 {
  52   SwfdecSandbox *sandbox = SWFDEC_SANDBOX (object);
  53
  54   swfdec_gc_object_mark (sandbox->Function);
  55   swfdec_gc_object_mark (sandbox->Function_prototype);
  56   swfdec_gc_object_mark (sandbox->Object);
  57   swfdec_gc_object_mark (sandbox->Object_prototype);
  58   swfdec_gc_object_mark (sandbox->MovieClip);
  59   swfdec_gc_object_mark (sandbox->Video);
  60
  61   SWFDEC_GC_OBJECT_CLASS (swfdec_sandbox_parent_class)->mark (object);
  62 }
  63
  64 static void
  65 swfdec_sandbox_dispose (GObject *object)
  66 {
  67   SwfdecSandbox *sandbox = SWFDEC_SANDBOX (object);
  68
  69   swfdec_url_free (sandbox->url);
  70
  71   G_OBJECT_CLASS (swfdec_sandbox_parent_class)->dispose (object);
  72 }
  73
  74 static void
  75 swfdec_sandbox_class_init (SwfdecSandboxClass *klass)
  76 {
  77   GObjectClass *object_class = G_OBJECT_CLASS (klass);
  78   SwfdecGcObjectClass *gc_class = SWFDEC_GC_OBJECT_CLASS (klass);
  79
  80   object_class->dispose = swfdec_sandbox_dispose;
  81
  82   gc_class->mark = swfdec_sandbox_mark;
  83 }
  84
  85 static void
  86 swfdec_sandbox_init (SwfdecSandbox *sandbox)
  87 {
  88   sandbox->type = SWFDEC_SANDBOX_NONE;
  89 }
  90
  91 static void
  92 swfdec_sandbox_initialize (SwfdecSandbox *sandbox, guint version)
  93 {
  94   SwfdecAsContext *context = swfdec_gc_object_get_context (sandbox);
  95   SwfdecPlayer *player = SWFDEC_PLAYER (context);
  96
  97   swfdec_sandbox_use (sandbox);
  98   if (context->state == SWFDEC_AS_CONTEXT_RUNNING)
  99     context->state = SWFDEC_AS_CONTEXT_NEW;
 100   swfdec_as_context_startup (context);
 101   /* reset state for initialization */
 102   /* FIXME: have a better way to do this */
 103   context->state = SWFDEC_AS_CONTEXT_NEW;
 104   swfdec_sprite_movie_init_context (player);
 105   swfdec_video_movie_init_context (player);
 106   swfdec_net_stream_init_context (player);
 107
 108   swfdec_as_context_run_init_script (context, swfdec_initialize,
 109       sizeof (swfdec_initialize), version);
 110
 111   sandbox->Function = context->Function;
 112   sandbox->Function_prototype = context->Function_prototype;
 113   sandbox->Object = context->Object;
 114   sandbox->Object_prototype = context->Object_prototype;
 115
 116   if (context->state == SWFDEC_AS_CONTEXT_NEW)
 117     context->state = SWFDEC_AS_CONTEXT_RUNNING;
 118   swfdec_sandbox_unuse (sandbox);
 119 }
 120
 121 /**
 122  * swfdec_sandbox_set_allow_network:
 123  * @sandbox: a #SwfdecSandbox
 124  * @network: %TRUE if network access is possible
 125  *
 126  * Checks if the given sandbox may be loaded and if so initializes its type.
 127  * This function should be called on every new sandbox.
 128  *
 129  * Returns: %TRUE if the sandbox initialization could be finished as requested,
 130  *          %FALSE if not and it shouldn't be used.
 131  **/
 132 static gboolean
 133 swfdec_sandbox_set_allow_network (SwfdecSandbox *sandbox, gboolean network)
 134 {
 135   g_return_val_if_fail (SWFDEC_IS_SANDBOX (sandbox), FALSE);
 136
 137   switch (sandbox->type) {
 138     case SWFDEC_SANDBOX_REMOTE:
 139       return TRUE;
 140     case SWFDEC_SANDBOX_LOCAL_FILE:
 141       return !network;
 142     case SWFDEC_SANDBOX_LOCAL_NETWORK:
 143       return network;
 144     case SWFDEC_SANDBOX_LOCAL_TRUSTED:
 145       return TRUE;
 146     case SWFDEC_SANDBOX_NONE:
 147       break;
 148     default:
 149       g_assert_not_reached ();
 150       break;
 151   }
 152
 153   if (swfdec_url_is_local (sandbox->url)) {
 154     sandbox->type = network ? SWFDEC_SANDBOX_LOCAL_NETWORK : SWFDEC_SANDBOX_LOCAL_FILE;
 155   } else {
 156     sandbox->type = SWFDEC_SANDBOX_REMOTE;
 157   }
 158
 159   return TRUE;
 160 }
 161
 162 /**
 163  * swfdec_sandbox_get_for_url:
 164  * @player: a #SwfdecPlayer
 165  * @url: the URL this player refers to
 166  * @flash_version: The Flash version for looking up the sandbox
 167  * @allow_network: %TRUE to allow network access, %FALSE to only allow local
 168  *                 file access. See the documentation of the use_network flag
 169  *                 of the SWF FileAttributes tag for what that means.
 170  *
 171  * Checks if a sandbox is already in use for a given URL and if so, returns it.
 172  * Otherwise a new sandbox is created, initialized and returned.
 173  * Note that the given url must be a HTTP, HTTPS or a FILE url.
 174  *
 175  * Returns: the sandbox corresponding to the given URL or %NULL if no such
 176  *          sandbox is allowed.
 177  **/
 178 SwfdecSandbox *
 179 swfdec_sandbox_get_for_url (SwfdecPlayer *player, const SwfdecURL *url,
 180     guint flash_version, gboolean allow_network)
 181 {
 182   SwfdecPlayerPrivate *priv;
 183   SwfdecSandbox *sandbox;
 184   SwfdecURL *real;
 185   guint as_version;
 186   GSList *walk;
 187
 188   g_return_val_if_fail (SWFDEC_IS_PLAYER (player), NULL);
 189   g_return_val_if_fail (url != NULL, NULL);
 190
 191   priv = player->priv;
 192   real = swfdec_url_new_components (swfdec_url_get_protocol (url),
 193       swfdec_url_get_host (url), swfdec_url_get_port (url), NULL, NULL);
 194   as_version = flash_version < 7 ? 1 : 2;
 195
 196   for (walk = priv->sandboxes; walk; walk = walk->next) {
 197     sandbox = walk->data;
 198     if (sandbox->as_version == as_version &&
 199         swfdec_url_equal (sandbox->url, real))
 200       break;
 201   }
 202
 203   if (walk) {
 204     swfdec_url_free (real);
 205
 206     if (!swfdec_sandbox_set_allow_network (sandbox, allow_network))
 207       return NULL;
 208   } else {
 209     SwfdecAsContext *context = SWFDEC_AS_CONTEXT (player);
 210
 211     sandbox = g_object_new (SWFDEC_TYPE_SANDBOX, "context", context, NULL);
 212     sandbox->url = real;
 213     sandbox->as_version = as_version;
 214     priv->sandboxes = g_slist_append (priv->sandboxes, sandbox);
 215
 216     if (!swfdec_sandbox_set_allow_network (sandbox, allow_network))
 217       return NULL;
 218
 219     swfdec_sandbox_initialize (sandbox, flash_version);
 220   }
 221
 222
 223   return sandbox;
 224 }
 225
 226 /**
 227  * swfdec_sandbox_use:
 228  * @sandbox: the sandbox to use when executing scripts
 229  *
 230  * Sets @sandbox to be used for scripts that are going to be executed next. No
 231  * sandbox may be set yet. You must unset the sandbox with
 232  * swfdec_sandbox_unuse() after calling your script.
 233  **/
 234 void
 235 swfdec_sandbox_use (SwfdecSandbox *sandbox)
 236 {
 237   SwfdecAsContext *context;
 238   SwfdecPlayerPrivate *priv;
 239
 240   g_return_if_fail (SWFDEC_IS_SANDBOX (sandbox));
 241   g_return_if_fail (sandbox->type != SWFDEC_SANDBOX_NONE);
 242   g_return_if_fail (swfdec_gc_object_get_context (sandbox)->global == NULL);
 243
 244   context = swfdec_gc_object_get_context (sandbox);
 245   priv = SWFDEC_PLAYER (context)->priv;
 246   context->global = SWFDEC_AS_OBJECT (sandbox);
 247
 248   context->Function = sandbox->Function;
 249   context->Function_prototype = sandbox->Function_prototype;
 250   context->Object = sandbox->Object;
 251   context->Object_prototype = sandbox->Object_prototype;
 252 }
 253
 254 /**
 255  * swfdec_sandbox_try_use:
 256  * @sandbox: the sandbox to use
 257  *
 258  * Makes sure a sandbox is in use. If no sandbox is in use currently, use the
 259  * given @sandbox. This function is intended for cases where code can be called
 260  * from both inside scripts with a sandbox already set or outside with no
 261  * sandbox in use.
 262  *
 263  * Returns: %TRUE if the new sandbox will be used. You need to call
 264  *          swfdec_sandbox_unuse() afterwards. %FALSE if a sandbox is already in
 265  *          use.
 266  **/
 267 gboolean
 268 swfdec_sandbox_try_use (SwfdecSandbox *sandbox)
 269 {
 270   g_return_val_if_fail (SWFDEC_IS_SANDBOX (sandbox), FALSE);
 271   g_return_val_if_fail (sandbox->type != SWFDEC_SANDBOX_NONE, FALSE);
 272
 273   if (swfdec_gc_object_get_context (sandbox)->global)
 274     return FALSE;
 275
 276   swfdec_sandbox_use (sandbox);
 277   return TRUE;
 278 }
 279
 280 /**
 281  * swfdec_sandbox_unuse:
 282  * @sandbox: a #SwfdecSandbox
 283  *
 284  * Unsets the sandbox as the current sandbox for executing scripts.
 285  **/
 286 void
 287 swfdec_sandbox_unuse (SwfdecSandbox *sandbox)
 288 {
 289   SwfdecAsContext *context;
 290
 291   g_return_if_fail (SWFDEC_IS_SANDBOX (sandbox));
 292   g_return_if_fail (swfdec_gc_object_get_context (sandbox)->global == SWFDEC_AS_OBJECT (sandbox));
 293
 294   context = swfdec_gc_object_get_context (sandbox);
 295   context->global = NULL;
 296   context->Function = NULL;
 297   context->Function_prototype = NULL;
 298   context->Object = NULL;
 299   context->Object_prototype = NULL;
 300 }
 301