X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=lxcsu;h=85b1ff72826c38d005845c67ef5895a530c424fb;hb=df40f9604c78752536de9314f1f03744531d7915;hp=11f1cce478d736010621c3872dbb0f6f1d8eacaa;hpb=95a418bb1b3a3f1a7343d8186d2b99937e9aff0d;p=lxc-userspace.git diff --git a/lxcsu b/lxcsu index 11f1cce..85b1ff7 100755 --- a/lxcsu +++ b/lxcsu @@ -7,134 +7,9 @@ import pdb from argparse import ArgumentParser -drop_capabilities='cap_sys_admin,cap_sys_boot,cap_sys_module' - # can set to True here, but also use the -d option debug = False -#################### should go into a separate libvirtsystemd.py -# but we want to keep packaging simple for now - -# reproducing libvirt's systemd-oriented escaping mechanism -# http://code.metager.de/source/xref/lib/virt/src/util/virsystemd.c -# (see original code at the end of this file) - -def virSystemdEscapeName (name): - result='' - def ESCAPE(c,s): - # replace hex's output '0x..' into '\x..' - return s+hex(ord(c)).replace('0','\\',1) - VALID_CHARS = \ - "0123456789" + \ - "abcdefghijklmnopqrstuvwxyz" + \ - "ABCDEFGHIJKLMNOPQRSTUVWXYZ" + \ - ":-_.\\" - for c in name: - if c=='/': - result += '-' - elif c in '-\\' or c not in VALID_CHARS: - result=ESCAPE(c,result) - else: - result += c - return result - -#35static void virSystemdEscapeName(virBufferPtr buf, -#36 const char *name) -#37{ -#38 static const char hextable[16] = "0123456789abcdef"; -#39 -#40#define ESCAPE(c) \ -#41 do { \ -#42 virBufferAddChar(buf, '\\'); \ -#43 virBufferAddChar(buf, 'x'); \ -#44 virBufferAddChar(buf, hextable[(c >> 4) & 15]); \ -#45 virBufferAddChar(buf, hextable[c & 15]); \ -#46 } while (0) -#47 -#48#define VALID_CHARS \ -#49 "0123456789" \ -#50 "abcdefghijklmnopqrstuvwxyz" \ -#51 "ABCDEFGHIJKLMNOPQRSTUVWXYZ" \ -#52 ":-_.\\" -#53 -#54 if (*name == '.') { -#55 ESCAPE(*name); -#56 name++; -#57 } -#58 -#59 while (*name) { -#60 if (*name == '/') -#61 virBufferAddChar(buf, '-'); -#62 else if (*name == '-' || -#63 *name == '\\' || -#64 !strchr(VALID_CHARS, *name)) -#65 ESCAPE(*name); -#66 else -#67 virBufferAddChar(buf, *name); -#68 name++; -#69 } -#70 -#71#undef ESCAPE -#72#undef VALID_CHARS -#73} - -def virSystemdMakeScopeName (name, drivername, partition): - result='' - result += virSystemdEscapeName (partition) - result += '-' - result += virSystemdEscapeName (drivername) - result += '\\x2d' - result += virSystemdEscapeName (name) - result += '.scope' - return result - -#76char *virSystemdMakeScopeName(const char *name, -#77 const char *drivername, -#78 const char *partition) -#79{ -#80 virBuffer buf = VIR_BUFFER_INITIALIZER; -#81 -#82 if (*partition == '/') -#83 partition++; -#84 -#85 virSystemdEscapeName(&buf, partition); -#86 virBufferAddChar(&buf, '-'); -#87 virSystemdEscapeName(&buf, drivername); -#88 virBufferAddLit(&buf, "\\x2d"); -#89 virSystemdEscapeName(&buf, name); -#90 virBufferAddLit(&buf, ".scope"); -#91 -#92 if (virBufferError(&buf)) { -#93 virReportOOMError(); -#94 return NULL; -#95 } -#96 -#97 return virBufferContentAndReset(&buf); -#98} - -### our own additions -import os.path -def find_first_dir (candidates): - for candidate in candidates: - if os.path.isdir(candidate): return candidate - raise Exception,"Cannot find valid dir among %s"%'\n'.join(candidates) - -def find_sysfs_scope (subsystem, slice_name): - subsystem1=subsystem - subsystem2=subsystem - if subsystem=='cpuacct': - subsystem2='cpu,cpuacct' - candidates = [ - # for f16 and our locally brewed libvirt 1.0.4 - "/sys/fs/cgroup/%s/libvirt/lxc/%s"%(subsystem1, slice_name), - # f20 and libvirt 1.1.3 - "/sys/fs/cgroup/%s/machine.slice/%s"%(subsystem2, - virSystemdMakeScopeName(slice_name,'lxc','machine')), - ] - return find_first_dir (candidates) - -#################### end of libvirtsystemd.py - 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])] @@ -170,13 +45,13 @@ def umount(fs_dir, opts=''): def main (): parser = ArgumentParser() parser.add_argument("-n", "--nonet", - action="store_true", dest="netns", default=False, + action="store_true", dest="no_netns", default=False, help="Don't enter network namespace") parser.add_argument("-m", "--nomnt", - action="store_true", dest="mntns", default=False, + action="store_true", dest="no_mntns", default=False, help="Don't enter mount namespace") parser.add_argument("-p", "--nopid", - action="store_true", dest="pidns", default=False, + action="store_true", dest="no_pidns", default=False, help="Don't enter pid namespace") parser.add_argument("-r", "--root", action="store_true", dest="root", default=False, @@ -225,22 +100,27 @@ def main (): try: cmd = '/usr/bin/virsh --connect lxc:/// domid %s'%slice_name - pidnum = int(os.popen(cmd).read().rstrip()) + # convert to int as a minimal raincheck + driver_pid = int(os.popen(cmd).read().strip()) + # locate the pid for the - expected - single child, that would be the init for that VM + #init_pid = int(open("/proc/%s/task/%s/children"%(driver_pid,driver_pid)).read().strip()) + init_pid = int(os.popen('pgrep -P %s'%driver_pid).readlines()[0].strip()) + # Thierry: I am changing the code below to use child_pid instead of driver_pid + # for the namespace handling features, that I was able to check + # I've left the other ones as they were, i.e. using driver_pid, but I suspect + # they chould be changed as well + except: - print "Error finding slice %s"%slice_name + print "Domain %s not found"%slice_name exit(1) - pid = '%s'%pidnum - if debug: print "Found pidnum",pidnum - cmdline = open('/proc/%s/cmdline'%pidnum).read().rstrip('\n\x00') - arch = getarch('/proc/%s/exe'%pid) - - if (not pid): - print "Not started: %s"%slice_name + if not driver_pid or not init_pid: + print "Domain %s not started"%slice_name exit(1) - if arch is None: - arch = 'x86_64' + if debug: print "Found driver_pid",driver_pid,'and init_pid=',init_pid + # xxx probably init_pid here too + arch = getarch('/proc/%s/exe'%driver_pid) # Set sysctls specific to slice sysctls = [] @@ -255,7 +135,8 @@ def main (): sysctl_val = open(sysctl_file).read() sysctls.append((sysctl_file, sysctl_name, sysctl_val)) - subdirs = get_cgroup_subdirs_for_pid(pid) + # xxx probably init_pid here too + subdirs = get_cgroup_subdirs_for_pid(driver_pid) sysfs_root = '/sys/fs/cgroup' # If the slice is frozen, then we'll get an EBUSY when trying to write to the task @@ -297,21 +178,25 @@ def main (): pass else: if debug: print e - print "Error assigning cgroup %s (%s) for slice %s"%(current_cgroup,pid, slice_name) + print "Error assigning cgroup %s (pid=%s) for slice %s"%(current_cgroup,driver_pid, 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) + def chcontext (path): + retcod = setns.chcontext (path) + if retcod != 0: + print 'WARNING - setns(%s)=>%s (ignored)'%(path,retcod) + return retcod - if (not args.netns): - setns.chcontext('/proc/%s/ns/net'%pid) + # Use init_pid and not driver_pid to locate reference namespaces + ref_ns = "/proc/%s/ns/"%init_pid - if (not args.mntns): - setns.chcontext('/proc/%s/ns/mnt'%pid) + if True: chcontext(ref_ns+'uts') + if True: chcontext(ref_ns+'ipc') + + if (not args.no_pidns): chcontext(ref_ns+'pid') + if (not args.no_netns): chcontext(ref_ns+'net') + if (not args.no_mntns): chcontext(ref_ns+'mnt') proc_mounted = False if (not os.access('/proc/self',0)): @@ -333,6 +218,7 @@ def main (): for subsystem in ['cpuset','cpu,cpuacct','memory','devices','freezer','net_cls','blkio','perf_event','systemd']: fs_path = '/sys/fs/cgroup/%s'%subsystem if (not umount(fs_path,'-l')): + print 'WARNING - umount failed (ignored) with path=',fs_path pass # Leaving these comments for historical reference #print "Error disabling cgroup access" @@ -342,20 +228,7 @@ def main (): 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 + fork_pid = os.fork() def getuid (slicename): import pwd @@ -364,23 +237,22 @@ def main (): except: return - if (pid == 0): - cap_arg = '--drop='+drop_capabilities - + if (fork_pid == 0): if (not args.root): + setns.drop_caps() if (args.nosliceuid): # we still want to drop capabilities, but don't want to switch UIDs - exec_args = [arch,'/usr/sbin/capsh',cap_arg,'--','--login',]+args.command_to_run + exec_args = [arch,'/bin/sh','--login',]+args.command_to_run else: uid = getuid (slice_name) if not uid: print "lxcsu 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 + exec_args = [arch,'/bin/sh','--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 +# 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 + exec_args = [arch,'/bin/sh','--login']+args.command_to_run os.environ['SHELL'] = '/bin/sh' if os.path.exists('/etc/planetlab/lib/bind_public.so'): @@ -392,7 +264,7 @@ def main (): os.execv('/usr/bin/setarch',exec_args) else: setns.proc_umount() - _,status = os.waitpid(pid,0) + _,status = os.waitpid(fork_pid,0) exit(os.WEXITSTATUS(status)) if __name__ == '__main__':