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_RELAY)
  48
  49 static void
  50 swfdec_sandbox_dispose (GObject *object)
  51 {
  52   SwfdecSandbox *sandbox = SWFDEC_SANDBOX (object);
  53
  54   swfdec_url_free (sandbox->url);
  55
  56   G_OBJECT_CLASS (swfdec_sandbox_parent_class)->dispose (object);
  57 }
  58
  59 static void
  60 swfdec_sandbox_class_init (SwfdecSandboxClass *klass)
  61 {
  62   GObjectClass *object_class = G_OBJECT_CLASS (klass);
  63
  64   object_class->dispose = swfdec_sandbox_dispose;
  65 }
  66
  67 static void
  68 swfdec_sandbox_init (SwfdecSandbox *sandbox)
  69 {
  70   sandbox->type = SWFDEC_SANDBOX_NONE;
  71 }
  72
  73 static void
  74 swfdec_sandbox_initialize (SwfdecSandbox *sandbox, guint version)
  75 {
  76   SwfdecAsContext *context = swfdec_gc_object_get_context (sandbox);
  77   SwfdecPlayer *player = SWFDEC_PLAYER (context);
  78
  79   swfdec_sandbox_use (sandbox);
  80   if (context->state == SWFDEC_AS_CONTEXT_RUNNING)
  81     context->state = SWFDEC_AS_CONTEXT_NEW;
  82   swfdec_as_context_startup (context);
  83   /* reset state for initialization */
  84   /* FIXME: have a better way to do this */
  85   context->state = SWFDEC_AS_CONTEXT_NEW;
  86   swfdec_net_stream_init_context (player);
  87
  88   swfdec_as_context_run_init_script (context, swfdec_initialize,
  89       sizeof (swfdec_initialize), version);
  90
  91   if (context->state == SWFDEC_AS_CONTEXT_NEW)
  92     context->state = SWFDEC_AS_CONTEXT_RUNNING;
  93   swfdec_sandbox_unuse (sandbox);
  94 }
  95
  96 /**
  97  * swfdec_sandbox_set_allow_network:
  98  * @sandbox: a #SwfdecSandbox
  99  * @network: %TRUE if network access is possible
 100  *
 101  * Checks if the given sandbox may be loaded and if so initializes its type.
 102  * This function should be called on every new sandbox.
 103  *
 104  * Returns: %TRUE if the sandbox initialization could be finished as requested,
 105  *          %FALSE if not and it shouldn't be used.
 106  **/
 107 static gboolean
 108 swfdec_sandbox_set_allow_network (SwfdecSandbox *sandbox, gboolean network)
 109 {
 110   g_return_val_if_fail (SWFDEC_IS_SANDBOX (sandbox), FALSE);
 111
 112   switch (sandbox->type) {
 113     case SWFDEC_SANDBOX_REMOTE:
 114       return TRUE;
 115     case SWFDEC_SANDBOX_LOCAL_FILE:
 116       return !network;
 117     case SWFDEC_SANDBOX_LOCAL_NETWORK:
 118       return network;
 119     case SWFDEC_SANDBOX_LOCAL_TRUSTED:
 120       return TRUE;
 121     case SWFDEC_SANDBOX_NONE:
 122       break;
 123     default:
 124       g_assert_not_reached ();
 125       break;
 126   }
 127
 128   if (swfdec_url_is_local (sandbox->url)) {
 129     sandbox->type = network ? SWFDEC_SANDBOX_LOCAL_NETWORK : SWFDEC_SANDBOX_LOCAL_FILE;
 130   } else {
 131     sandbox->type = SWFDEC_SANDBOX_REMOTE;
 132   }
 133
 134   return TRUE;
 135 }
 136
 137 /**
 138  * swfdec_sandbox_get_for_url:
 139  * @player: a #SwfdecPlayer
 140  * @url: the URL this player refers to
 141  * @flash_version: The Flash version for looking up the sandbox
 142  * @allow_network: %TRUE to allow network access, %FALSE to only allow local
 143  *                 file access. See the documentation of the use_network flag
 144  *                 of the SWF FileAttributes tag for what that means.
 145  *
 146  * Checks if a sandbox is already in use for a given URL and if so, returns it.
 147  * Otherwise a new sandbox is created, initialized and returned.
 148  * Note that the given url must be a HTTP, HTTPS or a FILE url.
 149  *
 150  * Returns: the sandbox corresponding to the given URL or %NULL if no such
 151  *          sandbox is allowed.
 152  **/
 153 SwfdecSandbox *
 154 swfdec_sandbox_get_for_url (SwfdecPlayer *player, const SwfdecURL *url,
 155     guint flash_version, gboolean allow_network)
 156 {
 157   SwfdecPlayerPrivate *priv;
 158   SwfdecSandbox *sandbox;
 159   SwfdecURL *real;
 160   guint as_version;
 161   GSList *walk;
 162
 163   g_return_val_if_fail (SWFDEC_IS_PLAYER (player), NULL);
 164   g_return_val_if_fail (url != NULL, NULL);
 165
 166   priv = player->priv;
 167   real = swfdec_url_new_components (swfdec_url_get_protocol (url),
 168       swfdec_url_get_host (url), swfdec_url_get_port (url), NULL, NULL);
 169   as_version = flash_version < 7 ? 1 : 2;
 170
 171   for (walk = priv->sandboxes; walk; walk = walk->next) {
 172     sandbox = walk->data;
 173     if (sandbox->as_version == as_version &&
 174         swfdec_url_equal (sandbox->url, real))
 175       break;
 176   }
 177
 178   if (walk) {
 179     swfdec_url_free (real);
 180
 181     if (!swfdec_sandbox_set_allow_network (sandbox, allow_network))
 182       return NULL;
 183   } else {
 184     SwfdecAsContext *context = SWFDEC_AS_CONTEXT (player);
 185     SwfdecAsObject *object;
 186
 187     sandbox = g_object_new (SWFDEC_TYPE_SANDBOX, "context", context, NULL);
 188     sandbox->url = real;
 189     sandbox->as_version = as_version;
 190     priv->sandboxes = g_slist_append (priv->sandboxes, sandbox);
 191
 192     if (!swfdec_sandbox_set_allow_network (sandbox, allow_network))
 193       return NULL;
 194
 195     object = swfdec_as_object_new_empty (context);
 196     swfdec_as_object_set_relay (object, SWFDEC_AS_RELAY (sandbox));
 197
 198     swfdec_sandbox_initialize (sandbox, flash_version);
 199   }
 200
 201   return sandbox;
 202 }
 203
 204 /**
 205  * swfdec_sandbox_get:
 206  * @player: a SwfdecPlayer
 207  *
 208  * Gets the currently in-use sandbox.
 209  *
 210  * Returns: A #SwfdecSandbox
 211  **/
 212 SwfdecSandbox *
 213 swfdec_sandbox_get (SwfdecPlayer *player)
 214 {
 215   g_return_val_if_fail (SWFDEC_IS_PLAYER (player), NULL);
 216   g_return_val_if_fail (SWFDEC_AS_CONTEXT (player)->global != NULL, NULL);
 217   g_return_val_if_fail (SWFDEC_IS_SANDBOX (SWFDEC_AS_CONTEXT (player)->global->relay), NULL);
 218
 219   return SWFDEC_SANDBOX (SWFDEC_AS_CONTEXT (player)->global->relay);
 220 }
 221
 222 /**
 223  * swfdec_sandbox_use:
 224  * @sandbox: the sandbox to use when executing scripts
 225  *
 226  * Sets @sandbox to be used for scripts that are going to be executed next. No
 227  * sandbox may be set yet. You must unset the sandbox with
 228  * swfdec_sandbox_unuse() after calling your script.
 229  **/
 230 void
 231 swfdec_sandbox_use (SwfdecSandbox *sandbox)
 232 {
 233   SwfdecAsContext *context;
 234   SwfdecPlayerPrivate *priv;
 235
 236   g_return_if_fail (SWFDEC_IS_SANDBOX (sandbox));
 237   g_return_if_fail (sandbox->type != SWFDEC_SANDBOX_NONE);
 238   g_return_if_fail (swfdec_gc_object_get_context (sandbox)->global == NULL);
 239
 240   context = swfdec_gc_object_get_context (sandbox);
 241   priv = SWFDEC_PLAYER (context)->priv;
 242   context->global = swfdec_as_relay_get_as_object (SWFDEC_AS_RELAY (sandbox));
 243 }
 244
 245 /**
 246  * swfdec_sandbox_try_use:
 247  * @sandbox: the sandbox to use
 248  *
 249  * Makes sure a sandbox is in use. If no sandbox is in use currently, use the
 250  * given @sandbox. This function is intended for cases where code can be called
 251  * from both inside scripts with a sandbox already set or outside with no
 252  * sandbox in use.
 253  *
 254  * Returns: %TRUE if the new sandbox will be used. You need to call
 255  *          swfdec_sandbox_unuse() afterwards. %FALSE if a sandbox is already in
 256  *          use.
 257  **/
 258 gboolean
 259 swfdec_sandbox_try_use (SwfdecSandbox *sandbox)
 260 {
 261   g_return_val_if_fail (SWFDEC_IS_SANDBOX (sandbox), FALSE);
 262   g_return_val_if_fail (sandbox->type != SWFDEC_SANDBOX_NONE, FALSE);
 263
 264   if (swfdec_gc_object_get_context (sandbox)->global)
 265     return FALSE;
 266
 267   swfdec_sandbox_use (sandbox);
 268   return TRUE;
 269 }
 270
 271 /**
 272  * swfdec_sandbox_unuse:
 273  * @sandbox: a #SwfdecSandbox
 274  *
 275  * Unsets the sandbox as the current sandbox for executing scripts.
 276  **/
 277 void
 278 swfdec_sandbox_unuse (SwfdecSandbox *sandbox)
 279 {
 280   SwfdecAsContext *context;
 281
 282   g_return_if_fail (SWFDEC_IS_SANDBOX (sandbox));
 283   g_return_if_fail (swfdec_gc_object_get_context (sandbox)->global != NULL);
 284   g_return_if_fail (swfdec_gc_object_get_context (sandbox)->global->relay == SWFDEC_AS_RELAY (sandbox));
 285
 286   context = swfdec_gc_object_get_context (sandbox);
 287   context->global = NULL;
 288 }
 289
 290 gboolean
 291 swfdec_sandbox_allow (SwfdecSandbox *sandbox, SwfdecSandbox *other)
 292 {
 293   g_return_val_if_fail (SWFDEC_IS_SANDBOX (sandbox), FALSE);
 294   g_return_val_if_fail (SWFDEC_IS_SANDBOX (other), FALSE);
 295
 296   SWFDEC_FIXME ("implement script sandbox interaction");
 297   return TRUE;
 298 }
 299