Basic menuentry-retrieveing jail

grub-core/commands/configfile.c

@@ -27,28 +27,34 @@
 static grub_err_t
 grub_cmd_source (grub_command_t cmd, int argc, char **args)
 {
-  int new_env;
+  int new_env, jail;
 
   if (argc != 1)
     return grub_error (GRUB_ERR_BAD_ARGUMENT, "file name required");
 
-  new_env = (cmd->name[0] == 'c');
+  jail = (cmd->name[0] == 'j');
+  new_env = (cmd->name[jail ? 5 : 0] == 'c');
 
   if (new_env)
-    {
+    grub_cls ();
-      grub_cls ();
+
-      grub_env_context_open (1);
+  if (new_env && !jail)
-    }
+    grub_env_context_open ();
+  if (jail)
+    grub_env_jail_open (!new_env);
 
   grub_normal_execute (args[0], 1, ! new_env);
 
-  if (new_env)
+  if (new_env && !jail)
     grub_env_context_close ();
+  if (jail)
+    grub_env_jail_close (!new_env);
 
   return 0;
 }
 
 static grub_command_t cmd_configfile, cmd_source, cmd_dot;
+static grub_command_t cmd_jail_source, cmd_jail_configfile;
 
 GRUB_MOD_INIT(configfile)
 {
@@ -60,6 +66,19 @@ GRUB_MOD_INIT(configfile)
 			   N_("FILE"),
 			   N_("Load another config file without changing context.")
 			   );
+
+  cmd_jail_source =
+    grub_register_command ("jail_source", grub_cmd_source,
+			   N_("FILE"),
+			   N_("Load another config file without changing context but take only menuentries.")
+			   );
+
+  cmd_jail_configfile =
+    grub_register_command ("jail_configfile", grub_cmd_source,
+			   N_("FILE"),
+			   N_("Load another config file without changing context but take only menuentries.")
+			   );
+
   cmd_dot =
     grub_register_command (".", grub_cmd_source,
 			   N_("FILE"),
@@ -71,5 +90,7 @@ GRUB_MOD_FINI(configfile)
 {
   grub_unregister_command (cmd_configfile);
   grub_unregister_command (cmd_source);
+  grub_unregister_command (cmd_jail_configfile);
+  grub_unregister_command (cmd_jail_source);
   grub_unregister_command (cmd_dot);
 }

grub-core/commands/menuentry.c

@@ -274,7 +274,8 @@ void
 grub_menu_init (void)
 {
   cmd = grub_register_extcmd ("menuentry", grub_cmd_menuentry,
-			      GRUB_COMMAND_FLAG_BLOCKS,
+			      GRUB_COMMAND_FLAG_BLOCKS
+			      | GRUB_COMMAND_FLAG_UNJAILED,
 			      N_("BLOCK"), N_("Define a menuentry."), options);
 }
 

grub-core/commands/search_wrap.c

@@ -90,7 +90,7 @@ static grub_extcmd_t cmd;
 GRUB_MOD_INIT(search)
 {
   cmd =
-    grub_register_extcmd ("search", grub_cmd_search, 0,
+    grub_register_extcmd ("search", grub_cmd_search, GRUB_COMMAND_FLAG_UNJAILED,
 			  N_("[-f|-l|-u|-s|-n] [--hint HINT [--hint HINT] ...]"
 			     " NAME"),
 			  N_("Search devices by file, filesystem label"

grub-core/commands/test.c

@@ -423,8 +423,10 @@ GRUB_MOD_INIT(test)
 {
   cmd_1 = grub_register_command ("[", grub_cmd_test,
 				 N_("EXPRESSION ]"), N_("Evaluate an expression."));
+  cmd_1->flags |= GRUB_COMMAND_FLAG_UNJAILED;
   cmd_2 = grub_register_command ("test", grub_cmd_test,
 				 N_("EXPRESSION"), N_("Evaluate an expression."));
+  cmd_2->flags |= GRUB_COMMAND_FLAG_UNJAILED;
 }
 
 GRUB_MOD_FINI(test)

grub-core/kern/corecmd.c

@@ -178,9 +178,12 @@ grub_core_cmd_ls (struct grub_command *cmd __attribute__ ((unused)),
 void
 grub_register_core_commands (void)
 {
-  grub_register_command ("set", grub_core_cmd_set,
+  grub_command_t cmd;
-			 N_("[ENVVAR=VALUE]"),
+  cmd = grub_register_command ("set", grub_core_cmd_set,
-			 N_("Set an environment variable."));
+			       N_("[ENVVAR=VALUE]"),
+			       N_("Set an environment variable."));
+  if (cmd)
+    cmd->flags |= GRUB_COMMAND_FLAG_UNJAILED;
   grub_register_command ("unset", grub_core_cmd_unset,
 			 N_("ENVVAR"),
 			 N_("Remove an environment variable."));

grub-core/normal/context.c

@@ -52,8 +52,8 @@ grub_env_set_menu (grub_menu_t nmenu)
   current_menu->menu = nmenu;
 }
 
-grub_err_t
+static grub_err_t
-grub_env_context_open (int export)
+grub_env_new_context (int export_all)
 {
   struct grub_env_context *context;
   int i;
@@ -78,23 +78,36 @@ grub_env_context_open (int export)
       struct grub_env_var *var;
 
       for (var = context->prev->vars[i]; var; var = var->next)
-	{
+	if (var->global || export_all)
-	  if (export && var->global)
+	  {
-	    {
+	    if (grub_env_set (var->name, var->value) != GRUB_ERR_NONE)
-	      if (grub_env_set (var->name, var->value) != GRUB_ERR_NONE)
+	      {
-		{
+		grub_env_context_close ();
-		  grub_env_context_close ();
+		return grub_errno;
-		  return grub_errno;
+	      }
-		}
+	    grub_env_export (var->name);
-	      grub_env_export (var->name);
+	    grub_register_variable_hook (var->name, var->read_hook, var->write_hook);
-	      grub_register_variable_hook (var->name, var->read_hook, var->write_hook);
+	  }
-	    }
-	}
     }
 
   return GRUB_ERR_NONE;
 }
 
+grub_err_t
+grub_env_context_open (void)
+{
+  return grub_env_new_context (0);
+}
+
+int grub_jail_level = 0;
+
+grub_err_t
+grub_env_jail_open (int source)
+{
+  grub_jail_level++;
+  return grub_env_new_context (source);
+}
+
 grub_err_t
 grub_env_context_close (void)
 {
@@ -132,6 +145,36 @@ grub_env_context_close (void)
   return GRUB_ERR_NONE;
 }
 
+grub_err_t
+grub_env_jail_close (int source)
+{
+  grub_menu_t menu, menu2;
+  grub_menu_entry_t *last;
+  grub_err_t err;
+
+  if (source)
+    {
+      menu = grub_env_get_menu ();
+      grub_env_unset_menu ();
+    }
+  err = grub_env_context_close ();
+
+  if (source)
+    {
+      menu2 = grub_env_get_menu ();
+      
+      last = &menu2->entry_list;
+      while (*last)
+	last = &(*last)->next;
+      
+      *last = menu->entry_list;
+      menu2->size += menu->size;
+    }
+
+  grub_jail_level--;
+  return err;
+}
+
 grub_err_t
 grub_env_export (const char *name)
 {

grub-core/script/execute.c

@@ -611,8 +611,11 @@ grub_script_execute_cmdline (struct grub_script_cmd *cmd)
   /* Execute the GRUB command or function.  */
   if (grubcmd)
     {
-      if ((grubcmd->flags & GRUB_COMMAND_FLAG_BLOCKS) &&
+      if (grub_jail_level && !(grubcmd->flags & GRUB_COMMAND_FLAG_UNJAILED))
-	  (grubcmd->flags & GRUB_COMMAND_FLAG_EXTCMD))
+	ret = grub_error (GRUB_ERR_JAIL, "%s isn't allowed to execute in jail",
+			  cmdname);
+      else if ((grubcmd->flags & GRUB_COMMAND_FLAG_BLOCKS) &&
+	       (grubcmd->flags & GRUB_COMMAND_FLAG_EXTCMD))
 	ret = grub_extcmd_dispatcher (grubcmd, argc, args, argv.script);
       else
 	ret = (grubcmd->func) (grubcmd, argc, args);

include/grub/command.h

@@ -35,6 +35,8 @@ typedef enum grub_command_flags
     GRUB_COMMAND_ACCEPT_DASH = 0x80,
     /* This command accepts only options preceding direct arguments.  */
     GRUB_COMMAND_OPTIONS_AT_START = 0x100,
+    /* Can be executed in a jail.  */
+    GRUB_COMMAND_FLAG_UNJAILED = 0x200
   } grub_command_flags_t;
 
 struct grub_command;

include/grub/env.h

@@ -51,7 +51,7 @@ grub_err_t EXPORT_FUNC(grub_register_variable_hook) (const char *name,
 						     grub_env_read_hook_t read_hook,
 						     grub_env_write_hook_t write_hook);
 
-grub_err_t grub_env_context_open (int export);
+grub_err_t grub_env_context_open (void);
 grub_err_t grub_env_context_close (void);
 grub_err_t grub_env_export (const char *name);
 
@@ -59,4 +59,11 @@ void grub_env_unset_menu (void);
 grub_menu_t grub_env_get_menu (void);
 void grub_env_set_menu (grub_menu_t nmenu);
 
+grub_err_t
+grub_env_jail_open (int source);
+
+grub_err_t
+grub_env_jail_close (int source);
+
+
 #endif /* ! GRUB_ENV_HEADER */

include/grub/err.h

@@ -54,7 +54,8 @@ typedef enum
     GRUB_ERR_MENU,
     GRUB_ERR_TIMEOUT,
     GRUB_ERR_IO,
-    GRUB_ERR_ACCESS_DENIED
+    GRUB_ERR_ACCESS_DENIED,
+    GRUB_ERR_JAIL
   }
 grub_err_t;
 

include/grub/normal.h

@@ -115,4 +115,6 @@ void grub_normal_reset_more (void);
 
 void grub_xputs_normal (const char *str);
 
+extern int grub_jail_level;
+
 #endif /* ! GRUB_NORMAL_HEADER */