diff options
| -rw-r--r-- | Lib/rexec.py | 65 |
1 files changed, 53 insertions, 12 deletions
diff --git a/Lib/rexec.py b/Lib/rexec.py index 1dc9917..975bee0 100644 --- a/Lib/rexec.py +++ b/Lib/rexec.py @@ -1,7 +1,7 @@ """Restricted execution facilities. -The class RExec exports methods rexec(), reval(), rexecfile(), and -import_module(), which correspond roughly to the built-in operations +The class RExec exports methods r_exec(), r_eval(), r_execfile(), and +r_import(), which correspond roughly to the built-in operations exec, eval(), execfile() and import, but executing the code in an environment that only exposes those built-in operations that are deemed safe. To this end, a modest collection of 'fake' modules is @@ -14,7 +14,6 @@ variables like ok_builtin_modules or methods like make_sys(). XXX To do: - r_open should allow writing tmp dir - r_exec etc. with explicit globals/locals? (Use rexec("exec ... in ...")?) -- r_reload should reload from same location (that's one for ihooks?) """ @@ -61,10 +60,27 @@ class FileDelegate(FileBase): class RHooks(ihooks.Hooks): - def __init__(self, rexec, verbose=0): + def __init__(self, *args): + # Hacks to support both old and new interfaces: + # old interface was RHooks(rexec[, verbose]) + # new interface is RHooks([verbose]) + verbose = 0 + rexec = None + if args and type(args[-1]) == type(0): + verbose = args[-1] + args = args[:-1] + if args and hasattr(args[0], '__class__'): + rexec = args[0] + args = args[1:] + if args: + raise TypeError, "too many arguments" ihooks.Hooks.__init__(self, verbose) self.rexec = rexec + def set_rexec(self, rexec): + # Called by RExec instance to complete initialization + self.rexec = rexec + def is_builtin(self, name): return self.rexec.is_builtin(name) @@ -76,8 +92,8 @@ class RHooks(ihooks.Hooks): def load_source(self, *args): raise SystemError, "don't use this" def load_compiled(self, *args): raise SystemError, "don't use this" - def load_dynamic(self, *args): - raise ImportError, "import of dynamically loaded modules not allowed" + def load_dynamic(self, name, filename, file): + return self.rexec.load_dynamic(name, filename, file) def add_module(self, name): return self.rexec.add_module(name) @@ -130,11 +146,16 @@ class RExec(ihooks._Verbose): def __init__(self, hooks = None, verbose = 0): ihooks._Verbose.__init__(self, verbose) # XXX There's a circular reference here: - self.hooks = hooks or RHooks(self, verbose) + self.hooks = hooks or RHooks(verbose) + self.hooks.set_rexec(self) self.modules = {} - self.ok_builtin_modules = map(None, filter( - lambda mname: mname in sys.builtin_module_names, - self.ok_builtin_modules)) + self.ok_dynamic_modules = self.ok_builtin_modules + list = [] + for mname in self.ok_builtin_modules: + if mname in sys.builtin_module_names: + list.append(mname) + self.ok_builtin_modules = list + self.set_trusted_path() self.make_builtin() self.make_initial_modules() # make_sys must be last because it adds the already created @@ -143,6 +164,22 @@ class RExec(ihooks._Verbose): self.loader = RModuleLoader(self.hooks, verbose) self.importer = RModuleImporter(self.loader, verbose) + def set_trusted_path(self): + # Set the path from which dynamic modules may be loaded. + # Those dynamic modules must also occur in ok_builtin_modules + self.trusted_path = filter(os.path.isabs, sys.path) + + def load_dynamic(self, name, filename, file): + if name not in self.ok_dynamic_modules: + raise ImportError, "untrusted dynamic module: %s" % name + if sys.modules.has_key(name): + src = sys.modules[key] + else: + import imp + src = imp.load_dynamic(name, filename, file) + dst = self.copy_except(src, []) + return dst + def make_initial_modules(self): self.make_main() self.make_osname() @@ -186,8 +223,12 @@ class RExec(ihooks._Verbose): def copy_except(self, src, exceptions): dst = self.copy_none(src) for name in dir(src): - if name not in exceptions: - setattr(dst, name, getattr(src, name)) + setattr(dst, name, getattr(src, name)) + for name in exceptions: + try: + delattr(dst, name) + except KeyError: + pass return dst def copy_only(self, src, names): |