Setting tag lxctools-0.9-5

[lxc-userspace.git] / lxcsu

diff --git a/lxcsu b/lxcsu
index c076506..d805e7b 100644 (file)
--- a/lxcsu
+++ b/lxcsu
@@ -5,25 +5,29 @@ import setns
 import os
 import sys
 
-#from optparse import OptionParser
+from optparse import OptionParser
 
-drop_capabilities='cap_sys_admin,cap_sys_boot,cap_sys_module'.split(',')
+drop_capabilities='cap_sys_admin,cap_sys_boot,cap_sys_module'
+
+def umount(fs_dir):
+    output = os.popen('/bin/umount %s 2>&1'%fs_dir).read()
+    return ('device is busy' not in fs_dir)
 
-"""
 parser = OptionParser()
-parser.add_option("-n", "--net",
+parser.add_option("-n", "--nonet",
                   action="store_true", dest="netns", default=False,
-                  help="Enter network namespace")
-parser.add_option("-m", "--mnt",
+                  help="Don't enter network namespace")
+parser.add_option("-m", "--nomnt",
                   action="store_true", dest="mntns", default=False,
-                  help="Enter mount namespace")
-parser.add_option("-p", "--pid",
+                  help="Don't enter mount namespace")
+parser.add_option("-p", "--nopid",
                   action="store_true", dest="pidns", default=False,
-                  help="Enter pid namespace")
+                  help="Don't enter pid namespace")
+parser.add_option("-r", "--root",
+                  action="store_true", dest="root", default=False,
+                  help="Enter as root: be careful")
 
 (options, args) = parser.parse_args()
-"""
-args = sys.argv[1:]
 
 try:
        slice_name = args[0]
@@ -69,6 +73,12 @@ 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,
@@ -83,19 +93,44 @@ except:
     print "Error adding task to freezer cgroup. Slice is probably frozen: %s" % slice_name
     exit(1)
 
-r1 = setns.chcontext('/proc/%s/ns/uts'%pid)
-r2 = setns.chcontext('/proc/%s/ns/ipc'%pid)
-r3 = setns.chcontext('/proc/%s/ns/net'%pid)
+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):
+  open('/proc/lxcsu','w').write(pid)
 
-open('/proc/lxcsu','w').write(pid)
-open('/proc/pidsu','w').write(pid)
+if (not options.pidns):
+  open('/proc/pidsu','w').write(pid)
+
+# 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()
 
-cap_args = map(lambda c:'--drop='+c, drop_capabilities)
-    
 if (pid == 0):
-    os.execv('/usr/sbin/capsh',cap_args+['--','--login']+args[1:])
+    cap_arg = '--drop='+drop_capabilities
+    if (not options.root):
+      exec_args = ['/usr/sbin/capsh',cap_arg,'--','--login']+args[1:]
+    else:
+      exec_args = ['/usr/sbin/capsh','--','--login']+args[1:]
+
+
     os.environ['SHELL'] = '/bin/sh'
+    os.execv('/usr/sbin/capsh',exec_args)
 else:
-    os.waitpid(pid,0)
+    _,status = os.waitpid(pid,0)
+    exit(os.WEXITSTATUS(status))