diff options
Diffstat (limited to 'scripts/lib/mic/chroot.py')
| -rw-r--r-- | scripts/lib/mic/chroot.py | 343 |
1 files changed, 343 insertions, 0 deletions
diff --git a/scripts/lib/mic/chroot.py b/scripts/lib/mic/chroot.py new file mode 100644 index 0000000000..99fb9a2c17 --- /dev/null +++ b/scripts/lib/mic/chroot.py @@ -0,0 +1,343 @@ +#!/usr/bin/python -tt +# +# Copyright (c) 2009, 2010, 2011 Intel, Inc. +# +# 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; version 2 of the License +# +# 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., 59 +# Temple Place - Suite 330, Boston, MA 02111-1307, USA. + +from __future__ import with_statement +import os +import shutil +import subprocess + +from mic import msger +from mic.conf import configmgr +from mic.utils import misc, errors, runner, fs_related + +chroot_lockfd = -1 +chroot_lock = "" +BIND_MOUNTS = ( + "/proc", + "/proc/sys/fs/binfmt_misc", + "/sys", + "/dev", + "/dev/pts", + "/dev/shm", + "/var/lib/dbus", + "/var/run/dbus", + "/var/lock", + ) + +def cleanup_after_chroot(targettype,imgmount,tmpdir,tmpmnt): + if imgmount and targettype == "img": + imgmount.cleanup() + + if tmpdir: + shutil.rmtree(tmpdir, ignore_errors = True) + + if tmpmnt: + shutil.rmtree(tmpmnt, ignore_errors = True) + +def check_bind_mounts(chrootdir, bindmounts): + chrootmounts = [] + for mount in bindmounts.split(";"): + if not mount: + continue + + srcdst = mount.split(":") + if len(srcdst) == 1: + srcdst.append("none") + + if not os.path.isdir(srcdst[0]): + return False + + if srcdst[1] == "" or srcdst[1] == "none": + srcdst[1] = None + + if srcdst[0] in BIND_MOUNTS or srcdst[0] == '/': + continue + + if chrootdir: + if not srcdst[1]: + srcdst[1] = os.path.abspath(os.path.expanduser(srcdst[0])) + else: + srcdst[1] = os.path.abspath(os.path.expanduser(srcdst[1])) + + tmpdir = chrootdir + "/" + srcdst[1] + if os.path.isdir(tmpdir): + msger.warning("Warning: dir %s has existed." % tmpdir) + + return True + +def cleanup_mounts(chrootdir): + umountcmd = misc.find_binary_path("umount") + abs_chrootdir = os.path.abspath(chrootdir) + mounts = open('/proc/mounts').readlines() + for line in reversed(mounts): + if abs_chrootdir not in line: + continue + + point = line.split()[1] + + # '/' to avoid common name prefix + if abs_chrootdir == point or point.startswith(abs_chrootdir + '/'): + args = [ umountcmd, "-l", point ] + ret = runner.quiet(args) + if ret != 0: + msger.warning("failed to unmount %s" % point) + + return 0 + +def setup_chrootenv(chrootdir, bindmounts = None, mountparent = True): + global chroot_lockfd, chroot_lock + + def get_bind_mounts(chrootdir, bindmounts, mountparent = True): + chrootmounts = [] + if bindmounts in ("", None): + bindmounts = "" + + for mount in bindmounts.split(";"): + if not mount: + continue + + srcdst = mount.split(":") + srcdst[0] = os.path.abspath(os.path.expanduser(srcdst[0])) + if len(srcdst) == 1: + srcdst.append("none") + + # if some bindmount is not existed, but it's created inside + # chroot, this is not expected + if not os.path.exists(srcdst[0]): + os.makedirs(srcdst[0]) + + if not os.path.isdir(srcdst[0]): + continue + + if srcdst[0] in BIND_MOUNTS or srcdst[0] == '/': + msger.verbose("%s will be mounted by default." % srcdst[0]) + continue + + if srcdst[1] == "" or srcdst[1] == "none": + srcdst[1] = None + else: + srcdst[1] = os.path.abspath(os.path.expanduser(srcdst[1])) + if os.path.isdir(chrootdir + "/" + srcdst[1]): + msger.warning("%s has existed in %s , skip it."\ + % (srcdst[1], chrootdir)) + continue + + chrootmounts.append(fs_related.BindChrootMount(srcdst[0], + chrootdir, + srcdst[1])) + + """Default bind mounts""" + for pt in BIND_MOUNTS: + if not os.path.exists(pt): + continue + chrootmounts.append(fs_related.BindChrootMount(pt, + chrootdir, + None)) + + if mountparent: + chrootmounts.append(fs_related.BindChrootMount("/", + chrootdir, + "/parentroot", + "ro")) + + for kernel in os.listdir("/lib/modules"): + chrootmounts.append(fs_related.BindChrootMount( + "/lib/modules/"+kernel, + chrootdir, + None, + "ro")) + + return chrootmounts + + def bind_mount(chrootmounts): + for b in chrootmounts: + msger.verbose("bind_mount: %s -> %s" % (b.src, b.dest)) + b.mount() + + def setup_resolv(chrootdir): + try: + shutil.copyfile("/etc/resolv.conf", chrootdir + "/etc/resolv.conf") + except: + pass + + globalmounts = get_bind_mounts(chrootdir, bindmounts, mountparent) + bind_mount(globalmounts) + + setup_resolv(chrootdir) + + mtab = "/etc/mtab" + dstmtab = chrootdir + mtab + if not os.path.islink(dstmtab): + shutil.copyfile(mtab, dstmtab) + + chroot_lock = os.path.join(chrootdir, ".chroot.lock") + chroot_lockfd = open(chroot_lock, "w") + + return globalmounts + +def cleanup_chrootenv(chrootdir, bindmounts=None, globalmounts=()): + global chroot_lockfd, chroot_lock + + def bind_unmount(chrootmounts): + for b in reversed(chrootmounts): + msger.verbose("bind_unmount: %s -> %s" % (b.src, b.dest)) + b.unmount() + + def cleanup_resolv(chrootdir): + try: + fd = open(chrootdir + "/etc/resolv.conf", "w") + fd.truncate(0) + fd.close() + except: + pass + + def kill_processes(chrootdir): + import glob + for fp in glob.glob("/proc/*/root"): + try: + if os.readlink(fp) == chrootdir: + pid = int(fp.split("/")[2]) + os.kill(pid, 9) + except: + pass + + def cleanup_mountdir(chrootdir, bindmounts): + if bindmounts == "" or bindmounts == None: + return + chrootmounts = [] + for mount in bindmounts.split(";"): + if not mount: + continue + + srcdst = mount.split(":") + + if len(srcdst) == 1: + srcdst.append("none") + + if srcdst[0] == "/": + continue + + if srcdst[1] == "" or srcdst[1] == "none": + srcdst[1] = srcdst[0] + + srcdst[1] = os.path.abspath(os.path.expanduser(srcdst[1])) + tmpdir = chrootdir + "/" + srcdst[1] + if os.path.isdir(tmpdir): + if len(os.listdir(tmpdir)) == 0: + shutil.rmtree(tmpdir, ignore_errors = True) + else: + msger.warning("Warning: dir %s isn't empty." % tmpdir) + + chroot_lockfd.close() + bind_unmount(globalmounts) + + if not fs_related.my_fuser(chroot_lock): + tmpdir = chrootdir + "/parentroot" + if os.path.exists(tmpdir) and len(os.listdir(tmpdir)) == 0: + shutil.rmtree(tmpdir, ignore_errors = True) + + cleanup_resolv(chrootdir) + + if os.path.exists(chrootdir + "/etc/mtab"): + os.unlink(chrootdir + "/etc/mtab") + + kill_processes(chrootdir) + + cleanup_mountdir(chrootdir, bindmounts) + +def chroot(chrootdir, bindmounts = None, execute = "/bin/bash"): + def mychroot(): + os.chroot(chrootdir) + os.chdir("/") + + if configmgr.chroot['saveto']: + savefs = True + saveto = configmgr.chroot['saveto'] + wrnmsg = "Can't save chroot fs for dir %s exists" % saveto + if saveto == chrootdir: + savefs = False + wrnmsg = "Dir %s is being used to chroot" % saveto + elif os.path.exists(saveto): + if msger.ask("Dir %s already exists, cleanup and continue?" % + saveto): + shutil.rmtree(saveto, ignore_errors = True) + savefs = True + else: + savefs = False + + if savefs: + msger.info("Saving image to directory %s" % saveto) + fs_related.makedirs(os.path.dirname(os.path.abspath(saveto))) + runner.quiet("cp -af %s %s" % (chrootdir, saveto)) + devs = ['dev/fd', + 'dev/stdin', + 'dev/stdout', + 'dev/stderr', + 'etc/mtab'] + ignlst = [os.path.join(saveto, x) for x in devs] + map(os.unlink, filter(os.path.exists, ignlst)) + else: + msger.warning(wrnmsg) + + dev_null = os.open("/dev/null", os.O_WRONLY) + files_to_check = ["/bin/bash", "/sbin/init"] + + architecture_found = False + + """ Register statically-linked qemu-arm if it is an ARM fs """ + qemu_emulator = None + + for ftc in files_to_check: + ftc = "%s/%s" % (chrootdir,ftc) + + # Return code of 'file' is "almost always" 0 based on some man pages + # so we need to check the file existance first. + if not os.path.exists(ftc): + continue + + for line in runner.outs(['file', ftc]).splitlines(): + if 'ARM' in line: + qemu_emulator = misc.setup_qemu_emulator(chrootdir, "arm") + architecture_found = True + break + + if 'Intel' in line: + architecture_found = True + break + + if architecture_found: + break + + os.close(dev_null) + if not architecture_found: + raise errors.CreatorError("Failed to get architecture from any of the " + "following files %s from chroot." \ + % files_to_check) + + try: + msger.info("Launching shell. Exit to continue.\n" + "----------------------------------") + globalmounts = setup_chrootenv(chrootdir, bindmounts) + subprocess.call(execute, preexec_fn = mychroot, shell=True) + + except OSError, err: + raise errors.CreatorError("chroot err: %s" % str(err)) + + finally: + cleanup_chrootenv(chrootdir, bindmounts, globalmounts) + if qemu_emulator: + os.unlink(chrootdir + qemu_emulator) |