X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=lxcsu-internal;fp=lxcsu-internal;h=2e16c03a2ceb121a4f0bcc8c3051b9429d15df9e;hb=e0abda420d460dc1a717193b2eabc564bd81feb1;hp=e30358351fe4705ef0cd621cd2bae11e8315d84c;hpb=5644df40218b4c1c14ae96a3edca458586b3e9dc;p=lxc-userspace.git diff --git a/lxcsu-internal b/lxcsu-internal deleted file mode 100755 index e303583..0000000 --- a/lxcsu-internal +++ /dev/null @@ -1,225 +0,0 @@ -#!/usr/bin/python - - -import setns -import os - -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() - 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 output) - -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="*") - - args = parser.parse_args() - slice_name=args.slice_name - # support for either setting debug at the top of this file, or on the command-line - if args.debug: - global debug - debug=True - - 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') or (cmdline.startswith("init [")): - slice_spec = slice_path - arch = getarch('/proc/%s/exe'%pid) - 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' - - # Set sysctls specific to slice - sysctl_dir = '/etc/planetlab/vsys-attributes/%s'%slice_name - if (os.access(sysctl_dir,0)): - entries = os.listdir(sysctl_dir) - for e in entries: - prefix = 'vsys_sysctl.' - if (e.startswith(prefix)): - sysctl_file = '/'.join([sysctl_dir,e]) - sysctl_name = e[len(prefix):] - sysctl_val = open(sysctl_file).read() - os.system('sysctl -w %s=%s'%(sysctl_name,sysctl_val)) - - # 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 args.pidns): - setns.chcontext('/proc/%s/ns/pid'%pid) - - if (not args.netns): - setns.chcontext('/proc/%s/ns/net'%pid) - - if (not args.mntns): - setns.chcontext('/proc/%s/ns/mnt'%pid) - - - - proc_mounted = False - if (not os.access('/proc/self',0)): - proc_mounted = True - 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() - - # capsh has a --user option starting with f14 - # so if only for f12 we need to fake this one - # - # capsh.c does essentially the following when invoked with --user: - # pwd = getpwnam(user); ... - # ngroups = MAX_GROUPS; - # status = getgrouplist(user, pwd->pw_gid, groups, &ngroups); ... - # status = setgroups(ngroups, groups); ... - # status = setgid(pwd->pw_gid); ... - # status = setuid(pwd->pw_uid); ... - # however we cannot simulate that ourselves because if we did in this process then - # capsh could not be allowed to mess with caps any more - - def getuid (slicename): - import pwd - try: - return pwd.getpwnam(slicename).pw_uid - except: - return - - if (pid == 0): - cap_arg = '--drop='+drop_capabilities - - if (not args.root): - uid = getuid (slice_name) - if not uid: - print "lxcsu-internal could not spot %s in /etc/passwd - exiting"%slice_name - exit(1) - exec_args = [arch,'/usr/sbin/capsh',cap_arg,'--uid=%s'%uid,'--','--login',]+args.command_to_run -# once we can drop f12, it would be nicer to instead go for -# exec_args = [arch,'/usr/sbin/capsh',cap_arg,'--user=%s'%slice_name,'--','--login',]+args.command_to_run - else: - exec_args = [arch,'/usr/sbin/capsh','--','--login']+args.command_to_run - - os.environ['SHELL'] = '/bin/sh' - os.environ['HOME'] = '/home/%s'%slice_name - os.environ['LD_PRELOAD'] = '/etc/planetlab/lib/bind_public.so' - os.chdir("/home/%s"%(slice_name)) - if debug: print 'lxcsu-internal:execv:','/usr/bin/setarch',exec_args - os.execv('/usr/bin/setarch',exec_args) - else: - setns.proc_umount() - _,status = os.waitpid(pid,0) - exit(os.WEXITSTATUS(status)) - -if __name__ == '__main__': - main() diff --git a/lxcsu-internal b/lxcsu-internal new file mode 120000 index 0000000..2e16c03 --- /dev/null +++ b/lxcsu-internal @@ -0,0 +1 @@ +lxcsu \ No newline at end of file