84 lines
2.7 KiB
Python
84 lines
2.7 KiB
Python
|
|
|
|
# Copyright (C) 2016 Andrew Hamilton. All rights reserved.
|
|
# Licensed under the Artistic License 2.0.
|
|
|
|
import os
|
|
import subprocess
|
|
import tempfile
|
|
|
|
|
|
class OverlayfsMount():
|
|
|
|
def __init__(self, lower_dir, mount_point):
|
|
self.lower_dir = lower_dir
|
|
self.mount_point = mount_point
|
|
self.upper_dir = tempfile.mkdtemp()
|
|
self.work_dir = tempfile.mkdtemp()
|
|
option_string = ("lowerdir=%s,upperdir=%s,workdir=%s" %
|
|
(self.lower_dir, self.upper_dir, self.work_dir))
|
|
subprocess.check_call(["sudo", "mount", "-t", "overlay", "-o",
|
|
option_string, "overlay", self.mount_point],
|
|
stderr=subprocess.PIPE)
|
|
for command in ["chmod", "chown"]:
|
|
subprocess.check_call(["sudo", command, "--reference", lower_dir,
|
|
mount_point])
|
|
|
|
def __repr__(self):
|
|
return "<OverlayfsMount:%r over %r>" % (self.mount_point,
|
|
self.lower_dir)
|
|
|
|
def umount(self):
|
|
subprocess.check_call(["sudo", "umount", "--lazy", self.mount_point])
|
|
subprocess.check_call(["sudo", "rm", "-rf", self.upper_dir,
|
|
self.work_dir])
|
|
|
|
|
|
def _in_chroot(mount_point, command):
|
|
return ["sudo", "chroot", "--userspec=%s" % os.environ["USER"],
|
|
mount_point] + command
|
|
|
|
|
|
_IN_DIRECTORY_SCRIPT = os.path.join(os.path.dirname(__file__), "in-directory")
|
|
|
|
|
|
def _in_directory(directory_path, command):
|
|
return [_IN_DIRECTORY_SCRIPT, directory_path] + command
|
|
|
|
|
|
def _parse_proc_mounts():
|
|
with open("/proc/mounts") as file_:
|
|
for line in file_:
|
|
yield line.split()
|
|
|
|
|
|
def _find_mounts():
|
|
all_mounts = set(part[1] for part in _parse_proc_mounts())
|
|
mount_points = {"/", "/usr", "/bin", "/etc", "/lib", "/dev", "/home",
|
|
"/boot", "/opt", "/run", "/root", "/var"}
|
|
return all_mounts.intersection(mount_points)
|
|
|
|
|
|
class SandboxFs:
|
|
|
|
def __init__(self, mount_point):
|
|
self.mount_point = mount_point
|
|
self.overlay_mounts = []
|
|
|
|
def __repr__(self):
|
|
return "<SandboxFs:%r mounts:%r>" % (self.mount_point,
|
|
len(self.overlay_mounts))
|
|
|
|
def mount(self):
|
|
self.overlay_mounts = [OverlayfsMount(mount_point,
|
|
self.mount_point + mount_point)
|
|
for mount_point in sorted(_find_mounts())]
|
|
|
|
def umount(self):
|
|
for mount in reversed(self.overlay_mounts):
|
|
mount.umount()
|
|
self.overlay_mounts = []
|
|
|
|
def command(self, command, env=None):
|
|
return _in_chroot(self.mount_point,
|
|
_in_directory(os.getcwd(), command))
|