# (c) 2015, Joerg Thalheim # Copyright (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: Joerg Thalheim connection: lxc short_description: Run tasks in lxc containers via lxc python library description: - Run commands or put/fetch files to an existing lxc container using lxc python library version_added: "2.0" options: remote_addr: description: - Container identifier default: inventory_hostname vars: - name: ansible_host - name: ansible_lxc_host executable: default: /bin/sh description: - Shell executable vars: - name: ansible_executable - name: ansible_lxc_executable """ import os import shutil import traceback import select import fcntl import errno HAS_LIBLXC = False try: import lxc as _lxc HAS_LIBLXC = True except ImportError: pass from ansible import constants as C from ansible import errors from ansible.module_utils._text import to_bytes, to_native from ansible.plugins.connection import ConnectionBase class Connection(ConnectionBase): ''' Local lxc based connections ''' transport = 'lxc' has_pipelining = True become_methods = frozenset(C.BECOME_METHODS) default_user = 'root' def __init__(self, play_context, new_stdin, *args, **kwargs): super(Connection, self).__init__(play_context, new_stdin, *args, **kwargs) self.container_name = self._play_context.remote_addr self.container = None def _connect(self): ''' connect to the lxc; nothing to do here ''' super(Connection, self)._connect() if not HAS_LIBLXC: msg = "lxc bindings for python2 are not installed" raise errors.AnsibleError(msg) if self.container: return self._display.vvv("THIS IS A LOCAL LXC DIR", host=self.container_name) self.container = _lxc.Container(self.container_name) if self.container.state == "STOPPED": raise errors.AnsibleError("%s is not running" % self.container_name) def _communicate(self, pid, in_data, stdin, stdout, stderr): buf = {stdout: [], stderr: []} read_fds = [stdout, stderr] if in_data: write_fds = [stdin] else: write_fds = [] while len(read_fds) > 0 or len(write_fds) > 0: try: ready_reads, ready_writes, _ = select.select(read_fds, write_fds, []) except select.error as e: if e.args[0] == errno.EINTR: continue raise for fd in ready_writes: in_data = in_data[os.write(fd, in_data):] if len(in_data) == 0: write_fds.remove(fd) for fd in ready_reads: data = os.read(fd, 32768) if not data: read_fds.remove(fd) buf[fd].append(data) (pid, returncode) = os.waitpid(pid, 0) return returncode, b"".join(buf[stdout]), b"".join(buf[stderr]) def _set_nonblocking(self, fd): flags = fcntl.fcntl(fd, fcntl.F_GETFL) | os.O_NONBLOCK fcntl.fcntl(fd, fcntl.F_SETFL, flags) return fd 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) # python2-lxc needs bytes. python3-lxc needs text. executable = to_native(self._play_context.executable, errors='surrogate_or_strict') local_cmd = [executable, '-c', to_native(cmd, errors='surrogate_or_strict')] read_stdout, write_stdout = None, None read_stderr, write_stderr = None, None read_stdin, write_stdin = None, None try: read_stdout, write_stdout = os.pipe() read_stderr, write_stderr = os.pipe() kwargs = { 'stdout': self._set_nonblocking(write_stdout), 'stderr': self._set_nonblocking(write_stderr), 'env_policy': _lxc.LXC_ATTACH_CLEAR_ENV } if in_data: read_stdin, write_stdin = os.pipe() kwargs['stdin'] = self._set_nonblocking(read_stdin) self._display.vvv("EXEC %s" % (local_cmd), host=self.container_name) pid = self.container.attach(_lxc.attach_run_command, local_cmd, **kwargs) if pid == -1: msg = "failed to attach to container %s" % self.container_name raise errors.AnsibleError(msg) write_stdout = os.close(write_stdout) write_stderr = os.close(write_stderr) if read_stdin: read_stdin = os.close(read_stdin) return self._communicate(pid, in_data, write_stdin, read_stdout, read_stderr) finally: fds = [read_stdout, write_stdout, read_stderr, write_stderr, read_stdin, write_stdin] for fd in fds: if fd: os.close(fd) def put_file(self, in_path, out_path): ''' transfer a file from local to lxc ''' super(Connection, self).put_file(in_path, out_path) self._display.vvv("PUT %s TO %s" % (in_path, out_path), host=self.container_name) in_path = to_bytes(in_path, errors='surrogate_or_strict') out_path = to_bytes(out_path, errors='surrogate_or_strict') if not os.path.exists(in_path): msg = "file or module does not exist: %s" % in_path raise errors.AnsibleFileNotFound(msg) try: src_file = open(in_path, "rb") except IOError: traceback.print_exc() raise errors.AnsibleError("failed to open input file to %s" % in_path) try: def write_file(args): with open(out_path, 'wb+') as dst_file: shutil.copyfileobj(src_file, dst_file) try: self.container.attach_wait(write_file, None) except IOError: traceback.print_exc() msg = "failed to transfer file to %s" % out_path raise errors.AnsibleError(msg) finally: src_file.close() def fetch_file(self, in_path, out_path): ''' fetch a file from lxc to local ''' super(Connection, self).fetch_file(in_path, out_path) self._display.vvv("FETCH %s TO %s" % (in_path, out_path), host=self.container_name) in_path = to_bytes(in_path, errors='surrogate_or_strict') out_path = to_bytes(out_path, errors='surrogate_or_strict') try: dst_file = open(out_path, "wb") except IOError: traceback.print_exc() msg = "failed to open output file %s" % out_path raise errors.AnsibleError(msg) try: def write_file(args): try: with open(in_path, 'rb') as src_file: shutil.copyfileobj(src_file, dst_file) finally: # this is needed in the lxc child process # to flush internal python buffers dst_file.close() try: self.container.attach_wait(write_file, None) except IOError: traceback.print_exc() msg = "failed to transfer file from %s to %s" % (in_path, out_path) raise errors.AnsibleError(msg) finally: dst_file.close() def close(self): ''' terminate the connection; nothing to do here ''' super(Connection, self).close() self._connected = False