#!/usr/bin/python
-
-import setns
import os
import sys
from argparse import ArgumentParser
-
-drop_capabilities='cap_sys_admin,cap_sys_boot,cap_sys_module'
-
-debug = False
-
-def getarch(f):
- output = os.popen('readelf -h %s 2>&1'%f).readlines()
- if debug: print "readelf output %s lines"%len(output)
- classlines = [x for x in output if ('Class' in x.split(':')[0])]
- line = classlines[0]
- c = line.split(':')[1]
- if ('ELF64' in c):
- return 'x86_64'
- elif ('ELF32' in c):
- return 'i686'
- else:
- raise Exception('Could not determine architecture')
-
-def umount(fs_dir):
- output = os.popen('/bin/umount %s 2>&1'%fs_dir).read()
- return ('device is busy' not in fs_dir)
+LXCSU_INTERNAL='/usr/sbin/lxcsu-internal'
def main ():
parser = ArgumentParser()
- parser.add_argument("-n", "--nonet",
- action="store_true", dest="netns", default=False,
- help="Don't enter network namespace")
- parser.add_argument("-m", "--nomnt",
- action="store_true", dest="mntns", default=False,
- help="Don't enter mount namespace")
- parser.add_argument("-p", "--nopid",
- action="store_true", dest="pidns", default=False,
- help="Don't enter pid namespace")
- parser.add_argument("-r", "--root",
- action="store_true", dest="root", default=False,
- help="Enter as root: be careful")
- parser.add_argument("-d","--debug",
- action='store_true', dest='debug', default=False,
- help="debug option")
parser.add_argument ("slice_name")
parser.add_argument ("command_to_run",nargs="*")
options = parser.parse_args()
slice_name=options.slice_name
- global debug
- debug=options.debug
-
- try:
- cmd = 'grep %s /proc/*/cgroup | grep freezer'%slice_name
- output = os.popen(cmd).readlines()
- if debug: print "output of grep freezer has %s lines"%len(output)
- except:
- print "Error finding slice %s"%slice_name
- exit(1)
-
- slice_spec = None
-
- # provide a default as this is not always properly computed
- arch = None
-
- for e in output:
- try:
- l = e.rstrip()
- path = l.split(':')[0]
- comp = l.rsplit(':')[-1]
- slice_name_check = comp.rsplit('/')[-1]
- if debug: print "dealing with >%s<"%slice_name_check
-
- if (slice_name_check == slice_name):
- if debug: print "found %s"%slice_name
- slice_path = path
- pid = slice_path.split('/')[2]
- cmdline = open('/proc/%s/cmdline'%pid).read().rstrip('\n\x00')
- if (cmdline == '/sbin/init'):
- slice_spec = slice_path
- arch = getarch('/proc/%s/exe'%pid)
- if debug: print "setting arch",arch
- break
- except Exception,e:
- if debug:
- import traceback
- print "BEG lxcsu - ignoring exception"
- traceback.print_exc()
- print "END lxcsu - ignoring exception"
- pass
-
- if (not slice_spec or not pid):
- print "Not started: %s"%slice_name
- exit(1)
-
- if arch is None:
- arch = 'x86_64'
- if debug: print "WARNING: setting arch to default x86_64"
-
- # Enter cgroups
- try:
- for subsystem in ['cpuset','memory','blkio']:
- open('/sys/fs/cgroup/%s/libvirt/lxc/%s/tasks'%(subsystem,slice_name),'w').write(str(os.getpid()))
-
- except:
- print "Error assigning resources: %s"%slice_name
- exit(1)
-
- try:
- open('/sys/fs/cgroup/cpuacct/system/libvirtd.service/libvirt/lxc/%s/tasks'%slice_name,'w').write(str(os.getpid()))
- except:
- print "Error assigning cpuacct: %s" % slice_name
- exit(1)
-
- # If the slice is frozen, then we'll get an EBUSY when trying to write to the task
- # list for the freezer cgroup. Since the user couldn't do anything anyway, it's best
- # in this case to error out the shell. (an alternative would be to un-freeze it,
- # add the task, and re-freeze it)
- try:
- f=open('/sys/fs/cgroup/freezer/libvirt/lxc/%s/tasks'%(slice_name),'w')
- f.write(str(os.getpid()))
- # note: we need to call f.close() explicitly, or we'll get an exception in
- # the object destructor, which will not be caught
- f.close()
- except:
- print "Error adding task to freezer cgroup. Slice is probably frozen: %s" % slice_name
- exit(1)
-
- setns.chcontext('/proc/%s/ns/uts'%pid)
- setns.chcontext('/proc/%s/ns/ipc'%pid)
-
- if (not options.netns):
- setns.chcontext('/proc/%s/ns/net'%pid)
-
- if (not options.mntns):
- setns.chcontext('/proc/%s/ns/mnt'%pid)
-
- if (not options.pidns):
- setns.chcontext('/proc/%s/ns/pid'%pid)
-
- if (not os.access('/proc/self',0)):
- setns.proc_mount()
-
- # cgroups is not yet LXC-safe, so we need to use the course grained access control
- # strategy of unmounting the filesystem
-
- umount_result = True
- for subsystem in ['cpuset','cpu,cpuacct','memory','devices','freezer','net_cls','blkio','perf_event']:
- fs_path = '/sys/fs/cgroup/%s'%subsystem
- if (not umount(fs_path)):
- print "Error disabling cgroup access"
- exit(1)
-
- if (not umount('/sys/fs/cgroup')):
- print "Error disabling cgroup access"
- exit(1)
-
- pid = os.fork()
-
- if (pid == 0):
- cap_arg = '--drop='+drop_capabilities
-
- if (not options.root):
- exec_args = [arch,'/usr/sbin/capsh',cap_arg,'--','--login']+options.command_to_run
- else:
- exec_args = [arch,'/usr/sbin/capsh','--','--login']+options.command_to_run
+ commands = options.command_to_run
- if debug:
- print "exec'ing"
- for arg in exec_args: print ">%s<"%arg
- os.environ['SHELL'] = '/bin/sh'
- os.execv('/usr/bin/setarch',exec_args)
- else:
- _,status = os.waitpid(pid,0)
- exit(os.WEXITSTATUS(status))
+ exec_args = [LXCSU_INTERNAL,slice_name,'--']
+ exec_args+=commands
+ os.execv(LXCSU_INTERNAL,exec_args)
if __name__ == '__main__':
main()
git://git.onelab.eu / lxc-userspace.git / blobdiff