X-Git-Url: http://git.onelab.eu/?p=nodemanager.git;a=blobdiff_plain;f=tools.py;h=1cef74699ecbe58cac5b2d7cbc69e4d321ae82ba;hp=22895c4da311b7f3b2fb84a9aefd05f6f630a351;hb=ccc7b9c4b76a89faad66867b00d16ac45333b6de;hpb=030819db61f9c6316f1d44d7c3e3486348ae49cc diff --git a/tools.py b/tools.py index 22895c4..1cef746 100644 --- a/tools.py +++ b/tools.py @@ -1,5 +1,4 @@ -# $Id$ -# $URL$ +# -*- python-indent: 4 -*- """A few things that didn't seem to fit anywhere else.""" @@ -10,6 +9,9 @@ import fcntl import errno import threading import subprocess +import shutil +import sys +import signal import logger @@ -60,7 +62,7 @@ def daemon(): os.setsid() if os.fork() != 0: os._exit(0) os.chdir('/') - os.umask(0) + os.umask(0022) devnull = os.open(os.devnull, os.O_RDWR) os.dup2(devnull, 0) # xxx fixme - this is just to make sure that nothing gets stupidly lost - should use devnull @@ -69,7 +71,14 @@ def daemon(): os.dup2(crashlog, 2) def fork_as(su, function, *args): - """fork(), cd / to avoid keeping unused directories open, close all nonstandard file descriptors (to avoid capturing open sockets), fork() again (to avoid zombies) and call with arguments in the grandchild process. If is not None, set our group and user ids appropriately in the child process.""" + """ +fork(), cd / to avoid keeping unused directories open, +close all nonstandard file descriptors (to avoid capturing open sockets), +fork() again (to avoid zombies) and call +with arguments in the grandchild process. +If is not None, set our group and user ids + appropriately in the child process. + """ child_pid = os.fork() if child_pid == 0: try: @@ -91,9 +100,11 @@ def fork_as(su, function, *args): #################### # manage files def pid_file(): - """We use a pid file to ensure that only one copy of NM is running at a given time. + """ +We use a pid file to ensure that only one copy of NM is running at a given time. If successful, this function will write a pid file containing the pid of the current process. -The return value is the pid of the other running process, or None otherwise.""" +The return value is the pid of the other running process, or None otherwise. + """ other_pid = None if os.access(PID_FILE, os.F_OK): # check for a pid file handle = open(PID_FILE) # pid file exists, read it @@ -110,8 +121,11 @@ The return value is the pid of the other running process, or None otherwise.""" return other_pid def write_file(filename, do_write, **kw_args): - """Write file atomically by opening a temporary file, using to write that file, and then renaming the temporary file.""" - os.rename(write_temp_file(do_write, **kw_args), filename) + """ +Write file atomically by opening a temporary file, +using to write that file, and then renaming the temporary file. + """ + shutil.move(write_temp_file(do_write, **kw_args), filename) def write_temp_file(do_write, mode=None, uidgid=None): fd, temporary_filename = tempfile.mkstemp() @@ -122,13 +136,16 @@ def write_temp_file(do_write, mode=None, uidgid=None): finally: f.close() return temporary_filename -# replace a target file with a new contents - checks for changes -# can handle chmod if requested -# can also remove resulting file if contents are void, if requested -# performs atomically: -# writes in a tmp file, which is then renamed (from sliverauth originally) -# returns True if a change occurred, or the file is deleted def replace_file_with_string (target, new_contents, chmod=None, remove_if_empty=False): + """ +Replace a target file with a new contents +checks for changes: does not do anything if previous state was already right +can handle chmod if requested +can also remove resulting file if contents are void, if requested +performs atomically: +writes in a tmp file, which is then renamed (from sliverauth originally) +returns True if a change occurred, or the file is deleted + """ try: current=file(target).read() except: @@ -148,11 +165,10 @@ def replace_file_with_string (target, new_contents, chmod=None, remove_if_empty= os.close(fd) if os.path.exists(target): os.unlink(target) - os.rename(name,target) + shutil.move(name,target) if chmod: os.chmod(target,chmod) return True - #################### # utilities functions to get (cached) information from the node @@ -193,3 +209,324 @@ class NMLock: def release(self): logger.log("tools: Lock released.", 2) fcntl.lockf(self.fd, fcntl.LOCK_UN) + +#################### +# Utilities for getting the IP address of a LXC/Openvswitch slice. Do this by +# running ifconfig inside of the slice's context. + +def get_sliver_process(slice_name, process_cmdline): + """ + Utility function to find a process inside of an LXC sliver. Returns + (cgroup_fn, pid). cgroup_fn is the filename of the cgroup file for + the process, for example /proc/2592/cgroup. Pid is the process id of + the process. If the process is not found then (None, None) is returned. + """ + try: + cmd = 'grep %s /proc/*/cgroup | grep freezer'%slice_name + output = os.popen(cmd).readlines() + except: + # the slice couldn't be found + logger.log("get_sliver_process: couldn't find slice %s" % slice_name) + return (None, None) + + cgroup_fn = None + pid = None + for e in output: + try: + l = e.rstrip() + path = l.split(':')[0] + comp = l.rsplit(':')[-1] + slice_name_check = comp.rsplit('/')[-1] + # the lines below were added by Guilherme + # due to the ipv6 plugin requirements (LXC) + virt=get_node_virt() + if virt=='lxc': + slice_name_check = slice_name_check.rsplit('.')[0] + + if (slice_name_check == slice_name): + slice_path = path + pid = slice_path.split('/')[2] + cmdline = open('/proc/%s/cmdline'%pid).read().rstrip('\n\x00') + if (cmdline == process_cmdline): + cgroup_fn = slice_path + break + except: + break + + if (not cgroup_fn) or (not pid): + logger.log("get_sliver_process: process %s not running in slice %s" % (process_cmdline, slice_name)) + return (None, None) + + return (cgroup_fn, pid) + +################################################### +# Added by Guilherme Sperb Machado +################################################### + +try: + import re + import socket + import fileinput +except: + logger.log("Could not import 're', 'socket', or 'fileinput' python packages.") + +# TODO: is there anything better to do if the "libvirt", "sliver_libvirt", +# and "sliver_lxc" are not in place? +try: + import libvirt + from sliver_libvirt import Sliver_Libvirt + import sliver_lxc +except: + logger.log("Could not import 'sliver_lxc' or 'libvirt' or 'sliver_libvirt'.") +################################################### + +def get_sliver_ifconfig(slice_name, device="eth0"): + """ + return the output of "ifconfig" run from inside the sliver. + + side effects: adds "/usr/sbin" to sys.path + """ + + # See if setns is installed. If it's not then we're probably not running + # LXC. + if not os.path.exists("/usr/sbin/setns.so"): + return None + + # setns is part of lxcsu and is installed to /usr/sbin + if not "/usr/sbin" in sys.path: + sys.path.append("/usr/sbin") + import setns + + (cgroup_fn, pid) = get_sliver_process(slice_name, "/sbin/init") + if (not cgroup_fn) or (not pid): + return None + + path = '/proc/%s/ns/net'%pid + + result = None + try: + setns.chcontext(path) + + args = ["/sbin/ifconfig", device] + sub = subprocess.Popen(args, stderr = subprocess.PIPE, stdout = subprocess.PIPE) + sub.wait() + + if (sub.returncode != 0): + logger.log("get_slice_ifconfig: error in ifconfig: %s" % sub.stderr.read()) + + result = sub.stdout.read() + finally: + setns.chcontext("/proc/1/ns/net") + + return result + +def get_sliver_ip(slice_name): + ifconfig = get_sliver_ifconfig(slice_name) + if not ifconfig: + return None + + for line in ifconfig.split("\n"): + if "inet addr:" in line: + # example: ' inet addr:192.168.122.189 Bcast:192.168.122.255 Mask:255.255.255.0' + parts = line.strip().split() + if len(parts)>=2 and parts[1].startswith("addr:"): + return parts[1].split(":")[1] + + return None + +################################################### +# Author: Guilherme Sperb Machado +################################################### +# Get the slice ipv6 address +# Only for LXC! +################################################### +def get_sliver_ipv6(slice_name): + ifconfig = get_sliver_ifconfig(slice_name) + if not ifconfig: + return None,None + + # example: 'inet6 2001:67c:16dc:1302:5054:ff:fea7:7882 prefixlen 64 scopeid 0x0' + prog = re.compile(r'inet6\s+(.*)\s+prefixlen\s+(\d+)\s+scopeid\s+(.+)') + for line in ifconfig.split("\n"): + search = prog.search(line) + if search: + ipv6addr = search.group(1) + prefixlen = search.group(2) + return (ipv6addr,prefixlen) + return None,None + +################################################### +# Author: Guilherme Sperb Machado +################################################### +# Check if the address is a AF_INET6 family address +################################################### +def is_valid_ipv6(ipv6addr): + try: + socket.inet_pton(socket.AF_INET6, ipv6addr) + except socket.error: + return False + return True + +### this returns the kind of virtualization on the node +# either 'vs' or 'lxc' +# also caches it in /etc/planetlab/virt for next calls +# could be promoted to core nm if need be +virt_stamp="/etc/planetlab/virt" +def get_node_virt (): + try: + return file(virt_stamp).read().strip() + except: + pass + logger.log("Computing virt..") + try: + if subprocess.call ([ 'vserver', '--help' ]) ==0: virt='vs' + else: virt='lxc' + except: + virt='lxc' + with file(virt_stamp,"w") as f: + f.write(virt) + return virt + +### this return True or False to indicate that systemctl is present on that box +# cache result in memory as _has_systemctl +_has_systemctl=None +def has_systemctl (): + global _has_systemctl + if _has_systemctl is None: + _has_systemctl = (subprocess.call([ 'systemctl', '--help' ]) == 0) + return _has_systemctl + +################################################### +# Author: Guilherme Sperb Machado +################################################### +# This method was developed to support the ipv6 plugin +# Only for LXC! +################################################### +def reboot_slivers(): + type = 'sliver.LXC' + # connecting to the libvirtd + connLibvirt = Sliver_Libvirt.getConnection(type) + domains = connLibvirt.listAllDomains() + for domain in domains: + try: + domain.destroy() + logger.log("tools: DESTROYED %s" % (domain.name()) ) + domain.create() + logger.log("tools: CREATED %s" % (domain.name()) ) + except: + logger.log("tools: FAILED to reboot %s" % (domain.name()) ) + +################################################### +# Author: Guilherme Sperb Machado +################################################### +# Get the /etc/hosts file path +################################################### +def get_hosts_file_path(slicename): + containerDir = os.path.join(sliver_lxc.Sliver_LXC.CON_BASE_DIR, slicename) + return os.path.join(containerDir, 'etc', 'hosts') + +################################################### +# Author: Guilherme Sperb Machado +################################################### +# Search if there is a specific ipv6 address in the +# /etc/hosts file of a given slice +# If the parameter 'ipv6addr' is None, then search +# for any ipv6 address +################################################### +def search_ipv6addr_hosts(slicename, ipv6addr): + hostsFilePath = get_hosts_file_path(slicename) + found=False + try: + for line in fileinput.input(r'%s' % (hostsFilePath)): + if ipv6addr is not None: + if re.search(r'%s' % (ipv6addr), line): + found=True + else: + search = re.search(r'^(.*)\s+.*$', line) + if search: + ipv6candidate = search.group(1) + ipv6candidatestrip = ipv6candidate.strip() + valid = is_valid_ipv6(ipv6candidatestrip) + if valid: + found=True + fileinput.close() + return found + except: + logger.log("tools: FAILED to search %s in /etc/hosts file of slice=%s" % \ + (ipv6addr, slicename) ) + +################################################### +# Author: Guilherme Sperb Machado +################################################### +# Removes all ipv6 addresses from the /etc/hosts +# file of a given slice +################################################### +def remove_all_ipv6addr_hosts(slicename, node): + hostsFilePath = get_hosts_file_path(slicename) + try: + for line in fileinput.input(r'%s' % (hostsFilePath), inplace=True): + search = re.search(r'^(.*)\s+(%s|%s)$' % (node,'localhost'), line) + if search: + ipv6candidate = search.group(1) + ipv6candidatestrip = ipv6candidate.strip() + valid = is_valid_ipv6(ipv6candidatestrip) + if not valid: + print line, + fileinput.close() + logger.log("tools: REMOVED IPv6 address from /etc/hosts file of slice=%s" % \ + (slicename) ) + except: + logger.log("tools: FAILED to remove the IPv6 address from /etc/hosts file of slice=%s" % \ + (slicename) ) + +################################################### +# Author: Guilherme Sperb Machado +################################################### +# Adds an ipv6 address to the /etc/hosts file within a slice +################################################### +def add_ipv6addr_hosts_line(slicename, node, ipv6addr): + hostsFilePath = get_hosts_file_path(slicename) + logger.log("tools: %s" % (hostsFilePath) ) + # debugging purposes: + #string = "127.0.0.1\tlocalhost\n192.168.100.179\tmyplc-node1-vm.mgmt.local\n" + #string = "127.0.0.1\tlocalhost\n" + try: + with open(hostsFilePath, "a") as file: + file.write(ipv6addr + " " + node + "\n") + file.close() + logger.log("tools: ADDED IPv6 address to /etc/hosts file of slice=%s" % \ + (slicename) ) + except: + logger.log("tools: FAILED to add the IPv6 address to /etc/hosts file of slice=%s" % \ + (slicename) ) + + + +# how to run a command in a slice +# now this is a painful matter +# the problem is with capsh that forces a bash command to be injected in its exec'ed command +# so because lxcsu uses capsh, you cannot exec anything else than bash +# bottom line is, what actually needs to be called is +# vs: vserver exec slicename command and its arguments +# lxc: lxcsu slicename "command and its arguments" +# which, OK, is no big deal as long as the command is simple enough, +# but do not stretch it with arguments that have spaces or need quoting as that will become a nightmare +def command_in_slice (slicename, argv): + virt=get_node_virt() + if virt=='vs': + return [ 'vserver', slicename, 'exec', ] + argv + elif virt=='lxc': + # wrap up argv in a single string for -c + return [ 'lxcsu', slicename, ] + [ " ".join(argv) ] + logger.log("command_in_slice: WARNING: could not find a valid virt") + return argv + +#################### +def init_signals (): + def handler (signum, frame): + logger.log("Received signal %d - exiting"%signum) + os._exit(1) + signal.signal(signal.SIGHUP,handler) + signal.signal(signal.SIGQUIT,handler) + signal.signal(signal.SIGINT,handler) + signal.signal(signal.SIGTERM,handler)