# Based on local.py (c) 2012, Michael DeHaan # Based on chroot.py (c) 2013, Maykel Moya # (c) 2013, Michael Scherer # (c) 2015, Toshio Kuratomi # (c) 2017 Ansible Project # GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt) from __future__ import (absolute_import, division, print_function) __metaclass__ = type DOCUMENTATION = """ author: Michael Scherer connection: libvirt_lxc short_description: Run tasks in lxc containers via libvirt description: - Run commands or put/fetch files to an existing lxc container using libvirt version_added: "2.0" options: remote_addr: description: - Container identifier default: The set user as per docker's configuration vars: - name: ansible_host - name: ansible_libvirt_lxc_host """ import distutils.spawn import os import os.path import subprocess import traceback from ansible import constants as C from ansible.errors import AnsibleError from ansible.module_utils.six.moves import shlex_quote from ansible.module_utils._text import to_bytes from ansible.plugins.connection import ConnectionBase, BUFSIZE try: from __main__ import display except ImportError: from ansible.utils.display import Display display = Display() class Connection(ConnectionBase): ''' Local lxc based connections ''' transport = 'libvirt_lxc' has_pipelining = True # su currently has an undiagnosed issue with calculating the file # checksums (so copy, for instance, doesn't work right) # Have to look into that before re-enabling this become_methods = frozenset(C.BECOME_METHODS).difference(('su',)) default_user = 'root' def __init__(self, play_context, new_stdin, *args, **kwargs): super(Connection, self).__init__(play_context, new_stdin, *args, **kwargs) self.lxc = self._play_context.remote_addr self.virsh = self._search_executable('virsh') self._check_domain(self.lxc) def _search_executable(self, executable): cmd = distutils.spawn.find_executable(executable) if not cmd: raise AnsibleError("%s command not found in PATH") % executable return cmd def _check_domain(self, domain): p = subprocess.Popen([self.virsh, '-q', '-c', 'lxc:///', 'dominfo', to_bytes(domain)], stdout=subprocess.PIPE, stderr=subprocess.PIPE) p.communicate() if p.returncode: raise AnsibleError("%s is not a lxc defined in libvirt" % domain) def _connect(self): ''' connect to the lxc; nothing to do here ''' super(Connection, self)._connect() if not self._connected: display.vvv("THIS IS A LOCAL LXC DIR", host=self.lxc) self._connected = True def _buffered_exec_command(self, cmd, stdin=subprocess.PIPE): ''' run a command on the chroot. This is only needed for implementing put_file() get_file() so that we don't have to read the whole file into memory. compared to exec_command() it looses some niceties like being able to return the process's exit code immediately. ''' executable = C.DEFAULT_EXECUTABLE.split()[0] if C.DEFAULT_EXECUTABLE else '/bin/sh' local_cmd = [self.virsh, '-q', '-c', 'lxc:///', 'lxc-enter-namespace'] if C.DEFAULT_LIBVIRT_LXC_NOSECLABEL: local_cmd += ['--noseclabel'] local_cmd += [self.lxc, '--', executable, '-c', cmd] display.vvv("EXEC %s" % (local_cmd,), host=self.lxc) local_cmd = [to_bytes(i, errors='surrogate_or_strict') for i in local_cmd] p = subprocess.Popen(local_cmd, shell=False, stdin=stdin, stdout=subprocess.PIPE, stderr=subprocess.PIPE) return p def exec_command(self, cmd, in_data=None, sudoable=False): ''' run a command on the chroot ''' super(Connection, self).exec_command(cmd, in_data=in_data, sudoable=sudoable) p = self._buffered_exec_command(cmd) stdout, stderr = p.communicate(in_data) return (p.returncode, stdout, stderr) def _prefix_login_path(self, remote_path): ''' Make sure that we put files into a standard path If a path is relative, then we need to choose where to put it. ssh chooses $HOME but we aren't guaranteed that a home dir will exist in any given chroot. So for now we're choosing "/" instead. This also happens to be the former default. Can revisit using $HOME instead if it's a problem ''' if not remote_path.startswith(os.path.sep): remote_path = os.path.join(os.path.sep, remote_path) return os.path.normpath(remote_path) def put_file(self, in_path, out_path): ''' transfer a file from local to lxc ''' super(Connection, self).put_file(in_path, out_path) display.vvv("PUT %s TO %s" % (in_path, out_path), host=self.lxc) out_path = shlex_quote(self._prefix_login_path(out_path)) try: with open(to_bytes(in_path, errors='surrogate_or_strict'), 'rb') as in_file: if not os.fstat(in_file.fileno()).st_size: count = ' count=0' else: count = '' try: p = self._buffered_exec_command('dd of=%s bs=%s%s' % (out_path, BUFSIZE, count), stdin=in_file) except OSError: raise AnsibleError("chroot connection requires dd command in the chroot") try: stdout, stderr = p.communicate() except: traceback.print_exc() raise AnsibleError("failed to transfer file %s to %s" % (in_path, out_path)) if p.returncode != 0: raise AnsibleError("failed to transfer file %s to %s:\n%s\n%s" % (in_path, out_path, stdout, stderr)) except IOError: raise AnsibleError("file or module does not exist at: %s" % in_path) def fetch_file(self, in_path, out_path): ''' fetch a file from lxc to local ''' super(Connection, self).fetch_file(in_path, out_path) display.vvv("FETCH %s TO %s" % (in_path, out_path), host=self.lxc) in_path = shlex_quote(self._prefix_login_path(in_path)) try: p = self._buffered_exec_command('dd if=%s bs=%s' % (in_path, BUFSIZE)) except OSError: raise AnsibleError("chroot connection requires dd command in the chroot") with open(to_bytes(out_path, errors='surrogate_or_strict'), 'wb+') as out_file: try: chunk = p.stdout.read(BUFSIZE) while chunk: out_file.write(chunk) chunk = p.stdout.read(BUFSIZE) except: traceback.print_exc() raise AnsibleError("failed to transfer file %s to %s" % (in_path, out_path)) stdout, stderr = p.communicate() if p.returncode != 0: raise AnsibleError("failed to transfer file %s to %s:\n%s\n%s" % (in_path, out_path, stdout, stderr)) def close(self): ''' terminate the connection; nothing to do here ''' super(Connection, self).close() self._connected = False