From 5674a5bf3977aefa5f4acc811ea32e2f2326f3de Mon Sep 17 00:00:00 2001 From: =?utf8?q?St=C3=A9phane=20Graber?= Date: Tue, 4 Mar 2014 13:20:10 -0500 Subject: [PATCH] lxc-ls: Fix support of --nesting for unpriv MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit This reworks the way lxc-ls works in nesting mode. In the past it'd use attach_wait's subprocess function to call itself in the container's namespace, carefully only attaching to the namespaces it needed. This works great for system containers but not so much as soon as you also need to attach to userns. Instead this fix moves all of the container listing code into a get_containers function (hence the massive diff, sorry), this function is then called recursively. For running containers, the function is called through attach_wait inside the container's namespace, for stopped container, the function is simply called recursively with a base path (container's rootfs) in an attempt to find containers that way. Communication between the parent lxc-ls and the child lxc-ls is done through a temporary fd and serialized state using json (similar to what was done using stdout in the previous implementation). As get_global_config_item unfortunately caches the values, there's no easy way to figure out what the lxcpath should be for a root container when running as non-root, so just use @LXCPATH@ for now and have python do the parsing itself. As a result, the following things now work as expected: - listing nested unprivileged containers (root containers inside unpriv) - listing nested containers when they're not running - filtering containers in nesting mode (only the first level is filtered) - copy with invalid config (used to traceback) Signed-off-by: Stéphane Graber Acked-by: Serge E. Hallyn --- configure.ac | 1 + src/lxc/{lxc-ls => lxc-ls.in} | 357 +++++++++++++++++++--------------- 2 files changed, 205 insertions(+), 153 deletions(-) rename src/lxc/{lxc-ls => lxc-ls.in} (53%) diff --git a/configure.ac b/configure.ac index 47e3869c4..e35284038 100644 --- a/configure.ac +++ b/configure.ac @@ -696,6 +696,7 @@ AC_CONFIG_FILES([ src/Makefile src/lxc/Makefile src/lxc/lxc-checkconfig + src/lxc/lxc-ls src/lxc/lxc-start-ephemeral src/lxc/legacy/lxc-ls src/lxc/lxc.functions diff --git a/src/lxc/lxc-ls b/src/lxc/lxc-ls.in similarity index 53% rename from src/lxc/lxc-ls rename to src/lxc/lxc-ls.in index 065b3e826..0f8139115 100755 --- a/src/lxc/lxc-ls +++ b/src/lxc/lxc-ls.in @@ -31,12 +31,17 @@ import json import lxc import os import re +import shutil import tempfile import sys _ = gettext.gettext gettext.textdomain("lxc-ls") +# Constants +LXCPATH = "@LXCPATH@" +RUNTIME_PATH = "@RUNTIME_PATH@" + # Functions used later on def batch(iterable, cols=1): @@ -54,7 +59,7 @@ def batch(iterable, cols=1): yield fields -def getTerminalSize(): +def get_terminal_size(): import os env = os.environ @@ -84,27 +89,17 @@ def getTerminalSize(): return int(cr[1]), int(cr[0]) -def getSubContainers(container): - with open(os.devnull, "w") as fd: - fdnum, path = tempfile.mkstemp() - os.remove(path) - - fd = os.fdopen(fdnum) +def get_root_path(path): + lxc_path = LXCPATH + global_conf = "%s/etc/lxc/lxc.conf" % path + if os.path.exists(global_conf): + with open(global_conf, "r") as fd: + for line in fd: + if line.startswith("lxc.lxcpath"): + lxc_path = line.split("=")[-1].strip() + break + return lxc_path - container.attach_wait( - lxc.attach_run_command, [sys.argv[0], "--nesting"], - attach_flags=(lxc.LXC_ATTACH_REMOUNT_PROC_SYS), - namespaces=(lxc.CLONE_NEWNET + lxc.CLONE_NEWPID), - extra_env_vars=["NESTED=/proc/1/root/%s" % - lxc.default_config_path], - stdout=fd) - - fd.seek(0) - out = fd.read() - fd.close() - if out: - return json.loads(out) - return None # Constants FIELDS = ("name", "state", "ipv4", "ipv6", "autostart", "pid", @@ -158,11 +153,6 @@ if args.active: if not sys.stdout.isatty(): args.one = True -# Set the lookup path for the containers -# This value will contain the full path for a nested containers -# use args.lxcpath if you need the value relative to the container -nest_lxcpath = os.environ.get('NESTED', args.lxcpath) - # Turn args.fancy_format into a list args.fancy_format = args.fancy_format.strip().split(",") @@ -193,141 +183,202 @@ if args.nesting: parser.error(_("Showing nested containers requires setns to the " "PID namespace which your kernel doesn't support.")) +# Set the actual lxcpath value +if not args.lxcpath: + args.lxcpath = lxc.default_config_path + + # List of containers, stored as dictionaries -containers = [] -for container_name in lxc.list_containers(config_path=nest_lxcpath): - entry = {} - entry['name'] = container_name - - # Apply filter - if args.filter and not re.match(args.filter, container_name): - continue - - # Return before grabbing the object (non-root) - if not args.state and not args.fancy and not args.nesting: - containers.append(entry) - continue - - container = lxc.Container(container_name, args.lxcpath) - - if 'NESTED' in os.environ: - container.load_config(os.path.join(nest_lxcpath, container_name, - "config")) - - if container.controllable: - state = container.state - else: - state = 'UNKNOWN' - - # Filter by status - if args.state and state not in args.state: - continue - - # Nothing more is needed if we're not printing some fancy output - if not args.fancy and not args.nesting: - containers.append(entry) - continue - - # Some extra field we may want - if 'state' in args.fancy_format or args.nesting: - entry['state'] = state - - if 'pid' in args.fancy_format or args.nesting: - entry['pid'] = "-" - if state == 'UNKNOWN': - entry['pid'] = state - elif container.init_pid != -1: - entry['pid'] = str(container.init_pid) - - if 'autostart' in args.fancy_format or args.nesting: - entry['autostart'] = "NO" - try: - if container.get_config_item("lxc.start.auto") == "1": - entry['autostart'] = "YES" +def get_containers(fd=None, base="/", root=False): + containers = [] - groups = container.get_config_item("lxc.group") - if len(groups) > 0: - entry['autostart'] = "YES (%s)" % ", ".join(groups) - except KeyError: - pass + paths = [args.lxcpath] - if 'memory' in args.fancy_format or \ - 'ram' in args.fancy_format or \ - 'swap' in args.fancy_format: + if not root: + paths.append(get_root_path(base)) - if container.running: - try: - memory_total = int(container.get_cgroup_item( - "memory.usage_in_bytes")) - except: - memory_total = 0 + # Generate a unique list of valid paths + paths = set([os.path.normpath("%s/%s" % (base, path)) for path in paths]) + + for path in paths: + if not os.access(path, os.R_OK): + continue + + for container_name in lxc.list_containers(config_path=path): + entry = {} + entry['name'] = container_name + + # Apply filter + if root and args.filter and \ + not re.match(args.filter, container_name): + continue + + # Return before grabbing the object (non-root) + if not args.state and not args.fancy and not args.nesting: + containers.append(entry) + continue try: - memory_swap = int(container.get_cgroup_item( - "memory.memsw.usage_in_bytes")) + container = lxc.Container(container_name, path) except: - memory_swap = 0 - else: - memory_total = 0 - memory_swap = 0 - - if 'memory' in args.fancy_format: - if container.running: - entry['memory'] = "%sMB" % round(memory_total / 1048576, 2) - else: - entry['memory'] = "-" - - if 'ram' in args.fancy_format: - if container.running: - entry['ram'] = "%sMB" % round( - (memory_total - memory_swap) / 1048576, 2) - else: - entry['ram'] = "-" - - if 'swap' in args.fancy_format: - if container.running: - entry['swap'] = "%sMB" % round(memory_swap / 1048576, 2) - else: - entry['swap'] = "-" - - # Get the IPs - for family, protocol in {'inet': 'ipv4', 'inet6': 'ipv6'}.items(): - if protocol in args.fancy_format or args.nesting: - entry[protocol] = "-" - - if state == 'UNKNOWN': - entry[protocol] = state continue - if container.running: - if not SUPPORT_SETNS_NET: - entry[protocol] = 'UNKNOWN' - continue - - ips = container.get_ips(family=family) - if ips: - entry[protocol] = ", ".join(ips) - - # Append the container - containers.append(entry) - - # Nested containers - if args.nesting and container.state == "RUNNING": - sub = getSubContainers(container) - if sub: - for entry in sub: - if 'nesting_parent' not in entry: - entry['nesting_parent'] = [] - entry['nesting_parent'].insert(0, container_name) - entry['nesting_real_name'] = entry.get('nesting_real_name', - entry['name']) - entry['name'] = "%s/%s" % (container_name, entry['name']) - containers += sub - -# Deal with json output: -if 'NESTED' in os.environ: - print(json.dumps(containers)) - sys.exit(0) + if container.controllable: + state = container.state + else: + state = 'UNKNOWN' + + # Filter by status + if args.state and state not in args.state: + continue + + # Nothing more is needed if we're not printing some fancy output + if not args.fancy and not args.nesting: + containers.append(entry) + continue + + # Some extra field we may want + if 'state' in args.fancy_format or args.nesting: + entry['state'] = state + + if 'pid' in args.fancy_format or args.nesting: + entry['pid'] = "-" + if state == 'UNKNOWN': + entry['pid'] = state + elif container.init_pid != -1: + entry['pid'] = str(container.init_pid) + + if 'autostart' in args.fancy_format or args.nesting: + entry['autostart'] = "NO" + try: + if container.get_config_item("lxc.start.auto") == "1": + entry['autostart'] = "YES" + + groups = container.get_config_item("lxc.group") + if len(groups) > 0: + entry['autostart'] = "YES (%s)" % ", ".join(groups) + except KeyError: + pass + + if 'memory' in args.fancy_format or \ + 'ram' in args.fancy_format or \ + 'swap' in args.fancy_format: + + if container.running: + try: + memory_total = int(container.get_cgroup_item( + "memory.usage_in_bytes")) + except: + memory_total = 0 + + try: + memory_swap = int(container.get_cgroup_item( + "memory.memsw.usage_in_bytes")) + except: + memory_swap = 0 + else: + memory_total = 0 + memory_swap = 0 + + if 'memory' in args.fancy_format: + if container.running: + entry['memory'] = "%sMB" % round(memory_total / 1048576, 2) + else: + entry['memory'] = "-" + + if 'ram' in args.fancy_format: + if container.running: + entry['ram'] = "%sMB" % round( + (memory_total - memory_swap) / 1048576, 2) + else: + entry['ram'] = "-" + + if 'swap' in args.fancy_format: + if container.running: + entry['swap'] = "%sMB" % round(memory_swap / 1048576, 2) + else: + entry['swap'] = "-" + + # Get the IPs + for family, protocol in {'inet': 'ipv4', 'inet6': 'ipv6'}.items(): + if protocol in args.fancy_format or args.nesting: + entry[protocol] = "-" + + if state == 'UNKNOWN': + entry[protocol] = state + continue + + if container.running: + if not SUPPORT_SETNS_NET: + entry[protocol] = 'UNKNOWN' + continue + + ips = container.get_ips(family=family) + if ips: + entry[protocol] = ", ".join(ips) + + # Nested containers + if args.nesting: + if container.running: + # Recursive call in container namespace + temp_fd, temp_file = tempfile.mkstemp() + os.remove(temp_file) + + container.attach_wait(get_containers, temp_fd, + attach_flags=0) + + json_file = os.fdopen(temp_fd, "r") + json_file.seek(0) + + try: + sub_containers = json.loads(json_file.read()) + except: + sub_containers = [] + + json_file.close() + else: + def clear_lock(): + try: + lock_path = "%s/lock/lxc/%s/%s" % (RUNTIME_PATH, + path, + entry['name']) + if os.path.exists(lock_path): + if os.path.isdir(lock_path): + shutil.rmtree(lock_path) + else: + os.remove(lock_path) + except: + pass + + clear_lock() + + # Recursive call using container rootfs + sub_containers = get_containers( + base="%s/%s" % ( + base, container.get_config_item("lxc.rootfs"))) + + clear_lock() + + for sub in sub_containers: + if 'nesting_parent' not in sub: + sub['nesting_parent'] = [] + sub['nesting_parent'].insert(0, entry['name']) + sub['nesting_real_name'] = sub.get('nesting_real_name', + sub['name']) + sub['name'] = "%s/%s" % (entry['name'], sub['name']) + containers.append(sub) + + # Append the container + containers.append(entry) + + if fd: + json_file = os.fdopen(fd, "w+") + json_file.write(json.dumps(containers)) + return + + return containers + +containers = get_containers(root=True) # Print the list ## Standard list with one entry per line @@ -348,7 +399,7 @@ if not args.fancy and not args.one: container_names.append(container['name']) # Figure out how many we can put per line - width = getTerminalSize()[0] + width = get_terminal_size()[0] entries = int(width / (field_maxlength + 2)) if entries == 0: -- 2.39.5