diff --git a/plugins/connection/libvirt_lxc.py b/plugins/connection/libvirt_lxc.py new file mode 100644 index 0000000000..4ad0b3eacb --- /dev/null +++ b/plugins/connection/libvirt_lxc.py @@ -0,0 +1,181 @@ +# 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 + options: + remote_addr: + description: + - Container identifier + default: The set user as Libvirt LXC 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 +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 + default_user = 'root' + has_tty = False + + 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 Exception: + 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 Exception: + 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