~azzar1/unity/add-show-desktop-key

#!/usr/bin/python

# IVLE - Informatics Virtual Learning Environment

# Copyright (C) 2009 The University of Melbourne

#

# This program is free software; you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation; either version 2 of the License, or

# (at your option) any later version.

#

# This program is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

# GNU General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with this program; if not, write to the Free Software

# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

import optparse

import os

import stat

import sys

import shutil

import ivle.config

import ivle.jailbuilder.debian

class UnsafeJail(Exception):

    pass

usage = """usage: %prog [options]

(requires root)

Builds or updates the base IVLE jail."""

# Requires root

if os.getuid() != 0:

    print >> sys.stderr, "This script requires root privileges to run"

    sys.exit(1)

conf = ivle.config.Config()

build_path = conf['paths']['jails']['template_build']

# Parse arguments

parser = optparse.OptionParser(usage)

parser.add_option("-r", "--recreate",

    action="store_true", dest="recreate",

    help='''Completely recreate the jail - don't just update its IVLE code.

Be warned, this may download hundreds of megabytes!''')

parser.add_option("-u", "--upgrade",

    action="store_true", dest="upgrade",

    help='''Apply any package updates in the jail.''')

parser.add_option("-m", "--mirror",

    action="store", dest="apt_mirror",

    help="Sets the apt mirror.", default=conf['jail']['mirror'])

parser.add_option("--python-site-packages",

    action="store", dest="python_site_packages",

    help="Path to Python site packages directory inside the jail.",

    default=None)

(options, args) = parser.parse_args(sys.argv)

if os.geteuid() != 0:

    print >> sys.stderr, "Must be root to run buildjail."

    sys.exit(1)

if not options.recreate and not os.path.exists(build_path):

    print >> sys.stderr, "No jail exists -- please rerun with -r."

    sys.exit(1)

if (options.python_site_packages is not None and

    options.python_site_packages[:1] not in (os.path.sep, os.path.altsep)):

    print >> sys.stderr, "python-site-packages must be an absolute path."

    sys.exit(1)

if options.recreate:

    options.upgrade = True

    # Create the jail and its subdirectories

    # Note: Other subdirs will be made by copying files

    if options.apt_mirror is not None:

        os.environ['MIRROR'] = options.apt_mirror

    os.system('rm -rf --one-file-system ' + build_path)

    ivle.jailbuilder.debian.debootstrap_create_jail(conf['jail']['suite'],

              build_path, mirror=options.apt_mirror)

    ivle.jailbuilder.debian.apt_update_cache(build_path)

    # Minimal required packages

    ivle.jailbuilder.debian.apt_install(build_path,

            ['python2.5', 'python-cjson', 'python-svn', 'python-configobj'])

    ivle.jailbuilder.debian.apt_clean(build_path)

if options.upgrade:

    # Run apt-get update, apt-get upgrade and apt-get clean.

    ivle.jailbuilder.debian.mangle_sources_list(build_path, clobber=True)

    ivle.jailbuilder.debian.mangle_sources_list(build_path, lines=[

            'deb %s %s%s %s' % (options.apt_mirror, conf['jail']['suite'],

                                pocket, ' '.join(['main', 'universe']))

            for pocket in ('', '-updates', '-security')])

    # Add any extra site apt sources.

    if conf['jail']['extra_sources']:

        ivle.jailbuilder.debian.mangle_sources_list(build_path,

                  conf['jail']['extra_sources'])

    # Add any extra site apt keys.

    if conf['jail']['extra_keys']:

        ivle.jailbuilder.debian.apt_add_key(build_path,

                                            conf['jail']['extra_keys'])

    ivle.jailbuilder.debian.apt_update_cache(build_path)

    ivle.jailbuilder.debian.apt_upgrade(build_path)

    # Install any extra site packages.

    if conf['jail']['extra_packages']:

        ivle.jailbuilder.debian.apt_install(build_path,

                  conf['jail']['extra_packages'])

    ivle.jailbuilder.debian.apt_clean(build_path)

    # Configure locales to allow en_US.UTF-8 (which IVLE uses)

    ivle.jailbuilder.debian._execute_in_chroot(build_path,

        ['locale-gen', 'en_US.UTF-8'])

if conf['jail']['devmode']:

    # Copy all console and operating system files into the jail

    services_path = os.path.join(conf['paths']['share'], 'services')

    jail_services_path = os.path.join(build_path, services_path[1:])

    if os.path.exists(jail_services_path):

        shutil.rmtree(jail_services_path)

    shutil.copytree(services_path, jail_services_path)

    # Also copy the IVLE lib directory into the jail

    # This is necessary for running certain services

    # ivle_site_packages is the IVLE install location outside the jail

    ivle_site_packages = os.path.dirname(ivle.__file__)

    if options.python_site_packages is None:

        # Get the site packages from the IVLE install location *OUTSIDE* the

        # jail. Warning! This only works if you have the same Python site

        # packages directory inside and out (ie. same Python version).

        # If not, you should use --python-site-packages.

        jail_site_packages = os.path.join(build_path, ivle_site_packages[1:])

    else:

        # User-specified site packages

        jail_site_packages = os.path.join(build_path,

                                options.python_site_packages[1:], "ivle")

    if os.path.exists(jail_site_packages):

        shutil.rmtree(jail_site_packages)

    shutil.copytree(ivle_site_packages, jail_site_packages)

    # And finally copy in /etc/hosts, /etc/resolv.conf and /etc/hostname,

    # so name resolution is less unlikely to work.

    shutil.copy(

        '/etc/resolv.conf', os.path.join(build_path, 'etc/resolv.conf'))

    shutil.copy('/etc/hosts', os.path.join(build_path, 'etc/hosts'))

    shutil.copy('/etc/hostname', os.path.join(build_path, 'etc/hostname'))

# Make /tmp and /var/lock un-world-writable. /tmp will be mounted over,

# and /var/{lock,tmp} should die.

for path in ('tmp', 'var/lock', 'var/tmp'):

    path = os.path.join(build_path, path)

    os.chmod(path, os.stat(path).st_mode & ~stat.S_IWOTH)

# Verify that nothing in the jail is world-writable.

# We don't want students to write into places that others can see.

try:

    for path, dirs, files in os.walk(build_path):

        for dname in dirs:

            d = os.path.join(path, dname)

            if os.path.islink(d):

                continue

            if os.stat(d).st_mode & stat.S_IWOTH:

                raise UnsafeJail(d)

        for fname in files:

            f = os.path.join(path, fname)

            if os.path.islink(f):

                continue

            if os.stat(f).st_mode & stat.S_IWOTH:

                if (os.path.dirname(f) == os.path.join(build_path, 'dev') and

                    os.path.basename(f) in ('ptmx', 'null', 'tty', 'full', 'zero',

                                            'random', 'urandom')

                    ):

                    continue

                raise UnsafeJail(f)

except UnsafeJail, e:

    print >> sys.stderr,"""Error: Jail contains world writable path: '%s'.

This is a security vulnerability as jail template contents are shared between 

users. Please either make this path world unwriteable or remove it from the 

jail."""%str(e)

    sys.exit(1)

# Copy jail template build to actual jail template

template_path = conf['paths']['jails']['template']

if os.spawnvp(os.P_WAIT, 'rsync', ['rsync', '-a', '--delete',

              build_path + '/', template_path]) != 0:

    print >> sys.stderr, "Jail copying failed."

    sys.exit(1)

# Now mangle things a bit, so we can bind-mount the user bits in.

# /etc/passwd and /etc/ivle/ivle.conf need to be symlinks to somewhere in /home

os.rename(os.path.join(template_path, 'etc/passwd'),

          os.path.join(template_path, 'home/.passwd')

          )

os.symlink('../home/.passwd', os.path.join(template_path, 'etc/passwd'))

os.makedirs(os.path.join(template_path, "etc/ivle"))

os.symlink('../../home/.ivle.conf',

           os.path.join(template_path, "etc/ivle/ivle.conf"))