mitogen/ansible_mitogen/connection.py

834 lines
28 KiB
Python

# Copyright 2017, David Wilson
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#
# 1. Redistributions of source code must retain the above copyright notice,
# this list of conditions and the following disclaimer.
#
# 2. Redistributions in binary form must reproduce the above copyright notice,
# this list of conditions and the following disclaimer in the documentation
# and/or other materials provided with the distribution.
#
# 3. Neither the name of the copyright holder nor the names of its contributors
# may be used to endorse or promote products derived from this software without
# specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
# POSSIBILITY OF SUCH DAMAGE.
from __future__ import absolute_import
from __future__ import unicode_literals
import logging
import os
import shlex
import stat
import time
import jinja2.runtime
import ansible.constants as C
import ansible.errors
import ansible.plugins.connection
import ansible.utils.shlex
import mitogen.unix
import mitogen.utils
import ansible_mitogen.parsing
import ansible_mitogen.process
import ansible_mitogen.services
import ansible_mitogen.target
LOG = logging.getLogger(__name__)
def optional_secret(value):
"""
Wrap `value` in :class:`mitogen.core.Secret` if it is not :data:`None`,
otherwise return :data:`None`.
"""
if value is not None:
return mitogen.core.Secret(value)
def parse_python_path(s):
"""
Given the string set for ansible_python_interpeter, parse it using shell
syntax and return an appropriate argument vector.
"""
if s:
return ansible.utils.shlex.shlex_split(s)
def _connect_local(spec):
"""
Return ContextService arguments for a local connection.
"""
return {
'method': 'local',
'kwargs': {
'python_path': spec['python_path'],
}
}
def _connect_ssh(spec):
"""
Return ContextService arguments for an SSH connection.
"""
if C.HOST_KEY_CHECKING:
check_host_keys = 'enforce'
else:
check_host_keys = 'ignore'
return {
'method': 'ssh',
'kwargs': {
'check_host_keys': check_host_keys,
'hostname': spec['remote_addr'],
'username': spec['remote_user'],
'password': optional_secret(spec['password']),
'port': spec['port'],
'python_path': spec['python_path'],
'identity_file': spec['private_key_file'],
'ssh_path': spec['ssh_executable'],
'connect_timeout': spec['ansible_ssh_timeout'],
'ssh_args': spec['ssh_args'],
'ssh_debug_level': spec['mitogen_ssh_debug_level'],
}
}
def _connect_docker(spec):
"""
Return ContextService arguments for a Docker connection.
"""
return {
'method': 'docker',
'kwargs': {
'username': spec['remote_user'],
'container': spec['remote_addr'],
'python_path': spec['python_path'],
'connect_timeout': spec['ansible_ssh_timeout'] or spec['timeout'],
}
}
def _connect_jail(spec):
"""
Return ContextService arguments for a FreeBSD jail connection.
"""
return {
'method': 'jail',
'kwargs': {
'username': spec['remote_user'],
'container': spec['remote_addr'],
'python_path': spec['python_path'],
'connect_timeout': spec['ansible_ssh_timeout'] or spec['timeout'],
}
}
def _connect_lxc(spec):
"""
Return ContextService arguments for an LXC Classic container connection.
"""
return {
'method': 'lxc',
'kwargs': {
'container': spec['remote_addr'],
'python_path': spec['python_path'],
'connect_timeout': spec['ansible_ssh_timeout'] or spec['timeout'],
}
}
def _connect_lxd(spec):
"""
Return ContextService arguments for an LXD container connection.
"""
return {
'method': 'lxd',
'kwargs': {
'container': spec['remote_addr'],
'python_path': spec['python_path'],
'connect_timeout': spec['ansible_ssh_timeout'] or spec['timeout'],
}
}
def _connect_machinectl(spec):
"""
Return ContextService arguments for a machinectl connection.
"""
return _connect_setns(dict(spec, mitogen_kind='machinectl'))
def _connect_setns(spec):
"""
Return ContextService arguments for a mitogen_setns connection.
"""
return {
'method': 'setns',
'kwargs': {
'container': spec['remote_addr'],
'username': spec['remote_user'],
'python_path': spec['python_path'],
'kind': spec['mitogen_kind'],
'docker_path': spec['mitogen_docker_path'],
'lxc_info_path': spec['mitogen_lxc_info_path'],
'machinectl_path': spec['mitogen_machinectl_path'],
}
}
def _connect_su(spec):
"""
Return ContextService arguments for su as a become method.
"""
return {
'method': 'su',
'enable_lru': True,
'kwargs': {
'username': spec['become_user'],
'password': optional_secret(spec['become_pass']),
'python_path': spec['python_path'],
'su_path': spec['become_exe'],
'connect_timeout': spec['timeout'],
}
}
def _connect_sudo(spec):
"""
Return ContextService arguments for sudo as a become method.
"""
return {
'method': 'sudo',
'enable_lru': True,
'kwargs': {
'username': spec['become_user'],
'password': optional_secret(spec['become_pass']),
'python_path': spec['python_path'],
'sudo_path': spec['become_exe'],
'connect_timeout': spec['timeout'],
'sudo_args': spec['sudo_args'],
}
}
def _connect_doas(spec):
"""
Return ContextService arguments for doas as a become method.
"""
return {
'method': 'doas',
'enable_lru': True,
'kwargs': {
'username': spec['become_user'],
'password': optional_secret(spec['become_pass']),
'python_path': spec['python_path'],
'doas_path': spec['become_exe'],
'connect_timeout': spec['timeout'],
}
}
def _connect_mitogen_su(spec):
"""
Return ContextService arguments for su as a first class connection.
"""
return {
'method': 'su',
'kwargs': {
'username': spec['remote_user'],
'password': optional_secret(spec['password']),
'python_path': spec['python_path'],
'su_path': spec['become_exe'],
'connect_timeout': spec['timeout'],
}
}
def _connect_mitogen_sudo(spec):
"""
Return ContextService arguments for sudo as a first class connection.
"""
return {
'method': 'sudo',
'kwargs': {
'username': spec['remote_user'],
'password': optional_secret(spec['password']),
'python_path': spec['python_path'],
'sudo_path': spec['become_exe'],
'connect_timeout': spec['timeout'],
'sudo_args': spec['sudo_args'],
}
}
def _connect_mitogen_doas(spec):
"""
Return ContextService arguments for doas as a first class connection.
"""
return {
'method': 'doas',
'kwargs': {
'username': spec['remote_user'],
'password': optional_secret(spec['password']),
'python_path': spec['python_path'],
'doas_path': spec['become_exe'],
'connect_timeout': spec['timeout'],
}
}
#: Mapping of connection method names to functions invoked as `func(spec)`
#: generating ContextService keyword arguments matching a connection
#: specification.
CONNECTION_METHOD = {
'docker': _connect_docker,
'jail': _connect_jail,
'local': _connect_local,
'lxc': _connect_lxc,
'lxd': _connect_lxd,
'machinectl': _connect_machinectl,
'setns': _connect_setns,
'ssh': _connect_ssh,
'su': _connect_su,
'sudo': _connect_sudo,
'doas': _connect_doas,
'mitogen_su': _connect_mitogen_su,
'mitogen_sudo': _connect_mitogen_sudo,
'mitogen_doas': _connect_mitogen_doas,
}
def config_from_play_context(transport, inventory_name, connection):
"""
Return a dict representing all important connection configuration, allowing
the same functions to work regardless of whether configuration came from
play_context (direct connection) or host vars (mitogen_via=).
"""
return {
'transport': transport,
'inventory_name': inventory_name,
'remote_addr': connection._play_context.remote_addr,
'remote_user': connection._play_context.remote_user,
'become': connection._play_context.become,
'become_method': connection._play_context.become_method,
'become_user': connection._play_context.become_user,
'become_pass': connection._play_context.become_pass,
'password': connection._play_context.password,
'port': connection._play_context.port,
'python_path': parse_python_path(connection.python_path),
'private_key_file': connection._play_context.private_key_file,
'ssh_executable': connection._play_context.ssh_executable,
'timeout': connection._play_context.timeout,
'ansible_ssh_timeout': connection.ansible_ssh_timeout,
'ssh_args': [
mitogen.core.to_text(term)
for s in (
getattr(connection._play_context, 'ssh_args', ''),
getattr(connection._play_context, 'ssh_common_args', ''),
getattr(connection._play_context, 'ssh_extra_args', '')
)
for term in ansible.utils.shlex.shlex_split(s or '')
],
'become_exe': connection._play_context.become_exe,
'sudo_args': [
mitogen.core.to_text(term)
for s in (
connection._play_context.sudo_flags,
connection._play_context.become_flags
)
for term in ansible.utils.shlex.shlex_split(s or '')
],
'mitogen_via': connection.mitogen_via,
'mitogen_kind': connection.mitogen_kind,
'mitogen_docker_path': connection.mitogen_docker_path,
'mitogen_lxc_info_path': connection.mitogen_lxc_info_path,
'mitogen_machinectl_path': connection.mitogen_machinectl_path,
'mitogen_ssh_debug_level': connection.mitogen_ssh_debug_level,
}
def config_from_hostvars(transport, inventory_name, connection,
hostvars, become_user):
"""
Override config_from_play_context() to take equivalent information from
host vars.
"""
config = config_from_play_context(transport, inventory_name, connection)
hostvars = dict(hostvars)
return dict(config, **{
'remote_addr': hostvars.get('ansible_host', inventory_name),
'become': bool(become_user),
'become_user': become_user,
'become_pass': None,
'remote_user': hostvars.get('ansible_user'), # TODO
'password': (hostvars.get('ansible_ssh_pass') or
hostvars.get('ansible_password')),
'port': hostvars.get('ansible_port'),
'python_path': parse_python_path(hostvars.get('ansible_python_interpreter')),
'private_key_file': (hostvars.get('ansible_ssh_private_key_file') or
hostvars.get('ansible_private_key_file')),
'mitogen_via': hostvars.get('mitogen_via'),
'mitogen_kind': hostvars.get('mitogen_kind'),
'mitogen_docker_path': hostvars.get('mitogen_docker_path'),
'mitogen_lxc_info_path': hostvars.get('mitogen_lxc_info_path'),
'mitogen_machinectl_path': hostvars.get('mitogen_machinctl_path'),
})
class Connection(ansible.plugins.connection.ConnectionBase):
#: mitogen.master.Broker for this worker.
broker = None
#: mitogen.master.Router for this worker.
router = None
#: mitogen.parent.Context representing the parent Context, which is
#: presently always the connection multiplexer process.
parent = None
#: mitogen.parent.Context for the target account on the target, possibly
#: reached via become.
context = None
#: mitogen.parent.Context for the login account on the target. This is
#: always the login account, even when become=True.
login_context = None
#: mitogen.parent.Context connected to the fork parent process in the
#: target user account.
fork_context = None
#: Only sudo, su, and doas are supported for now.
become_methods = ['sudo', 'su', 'doas']
#: Set to 'ansible_python_interpreter' by on_action_run().
python_path = None
#: Set to 'ansible_ssh_timeout' by on_action_run().
ansible_ssh_timeout = None
#: Set to 'mitogen_via' by on_action_run().
mitogen_via = None
#: Set to 'mitogen_kind' by on_action_run().
mitogen_kind = None
#: Set to 'mitogen_docker_path' by on_action_run().
mitogen_docker_path = None
#: Set to 'mitogen_lxc_info_path' by on_action_run().
mitogen_lxc_info_path = None
#: Set to 'mitogen_lxc_info_path' by on_action_run().
mitogen_machinectl_path = None
#: Set to 'mitogen_ssh_debug_level' by on_action_run().
mitogen_ssh_debug_level = None
#: Set to 'inventory_hostname' by on_action_run().
inventory_hostname = None
#: Set to 'hostvars' by on_action_run()
host_vars = None
#: Set to '_loader.get_basedir()' by on_action_run(). Used by mitogen_local
#: to change the working directory to that of the current playbook,
#: matching vanilla Ansible behaviour.
loader_basedir = None
#: Set after connection to the target context's home directory.
home_dir = None
def __init__(self, play_context, new_stdin, **kwargs):
assert ansible_mitogen.process.MuxProcess.unix_listener_path, (
'Mitogen connection types may only be instantiated '
'while the "mitogen" strategy is active.'
)
super(Connection, self).__init__(play_context, new_stdin)
def __del__(self):
"""
Ansible cannot be trusted to always call close() e.g. the synchronize
action constructs a local connection like this. So provide a destructor
in the hopes of catching these cases.
"""
# https://github.com/dw/mitogen/issues/140
self.close()
def on_action_run(self, task_vars, delegate_to_hostname, loader_basedir):
"""
Invoked by ActionModuleMixin to indicate a new task is about to start
executing. We use the opportunity to grab relevant bits from the
task-specific data.
:param dict task_vars:
Task variable dictionary.
:param str delegate_to_hostname:
:data:`None`, or the template-expanded inventory hostname this task
is being delegated to. A similar variable exists on PlayContext
when ``delegate_to:`` is active, however it is unexpanded.
:param str loader_basedir:
Loader base directory; see :attr:`loader_basedir`.
"""
self.ansible_ssh_timeout = task_vars.get('ansible_ssh_timeout',
C.DEFAULT_TIMEOUT)
self.python_path = task_vars.get('ansible_python_interpreter',
'/usr/bin/python')
self.mitogen_via = task_vars.get('mitogen_via')
self.mitogen_kind = task_vars.get('mitogen_kind')
self.mitogen_docker_path = task_vars.get('mitogen_docker_path')
self.mitogen_lxc_info_path = task_vars.get('mitogen_lxc_info_path')
self.mitogen_machinectl_path = task_vars.get('mitogen_machinectl_path')
self.mitogen_ssh_debug_level = task_vars.get('mitogen_ssh_debug_level')
self.inventory_hostname = task_vars['inventory_hostname']
self.host_vars = task_vars['hostvars']
self.delegate_to_hostname = delegate_to_hostname
self.loader_basedir = loader_basedir
self.close(new_task=True)
@property
def homedir(self):
self._connect()
return self.home_dir
@property
def connected(self):
return self.context is not None
def _config_from_via(self, via_spec):
"""
Produce a dict connection specifiction given a string `via_spec`, of
the form `[become_user@]inventory_hostname`.
"""
become_user, _, inventory_name = via_spec.rpartition('@')
via_vars = self.host_vars[inventory_name]
if isinstance(via_vars, jinja2.runtime.Undefined):
raise ansible.errors.AnsibleConnectionFailure(
self.unknown_via_msg % (
self.mitogen_via,
inventory_name,
)
)
return config_from_hostvars(
transport=via_vars.get('ansible_connection', 'ssh'),
inventory_name=inventory_name,
connection=self,
hostvars=via_vars,
become_user=become_user or None,
)
unknown_via_msg = 'mitogen_via=%s of %s specifies an unknown hostname'
via_cycle_msg = 'mitogen_via=%s of %s creates a cycle (%s)'
def _stack_from_config(self, config, stack=(), seen_names=()):
if config['inventory_name'] in seen_names:
raise ansible.errors.AnsibleConnectionFailure(
self.via_cycle_msg % (
config['mitogen_via'],
config['inventory_name'],
' -> '.join(reversed(
seen_names + (config['inventory_name'],)
)),
)
)
if config['mitogen_via']:
stack, seen_names = self._stack_from_config(
self._config_from_via(config['mitogen_via']),
stack=stack,
seen_names=seen_names + (config['inventory_name'],)
)
stack += (CONNECTION_METHOD[config['transport']](config),)
if config['become']:
stack += (CONNECTION_METHOD[config['become_method']](config),)
return stack, seen_names
def _connect_broker(self):
"""
Establish a reference to the Broker, Router and parent context used for
connections.
"""
if not self.broker:
self.broker = mitogen.master.Broker()
self.router, self.parent = mitogen.unix.connect(
path=ansible_mitogen.process.MuxProcess.unix_listener_path,
broker=self.broker,
)
def _config_from_direct_connection(self):
"""
"""
return config_from_play_context(
transport=self.transport,
inventory_name=self.inventory_hostname,
connection=self
)
def _config_from_delegate_to(self):
return config_from_hostvars(
transport=self._play_context.connection,
inventory_name=self.delegate_to_hostname,
connection=self,
hostvars=self.host_vars[self._play_context.delegate_to],
become_user=(self._play_context.become_user
if self._play_context.become
else None),
)
def _build_stack(self):
"""
Construct a list of dictionaries representing the connection
configuration between the controller and the target. This is
additionally used by the integration tests "mitogen_get_stack" action
to fetch the would-be connection configuration.
"""
if self.delegate_to_hostname is not None:
target_config = self._config_from_delegate_to()
else:
target_config = self._config_from_direct_connection()
stack, _ = self._stack_from_config(target_config)
return stack
def _connect_stack(self, stack):
"""
Pass `stack` to ContextService, requesting a copy of the context object
representing the target. If no connection exists yet, ContextService
will establish it before returning it or throwing an error.
"""
dct = self.parent.call_service(
service_name='ansible_mitogen.services.ContextService',
method_name='get',
stack=mitogen.utils.cast(list(stack)),
)
if dct['msg']:
if dct['method_name'] in self.become_methods:
raise ansible.errors.AnsibleModuleError(dct['msg'])
raise ansible.errors.AnsibleConnectionFailure(dct['msg'])
self.context = dct['context']
if self._play_context.become:
self.login_context = dct['via']
else:
self.login_context = self.context
self.fork_context = dct['init_child_result']['fork_context']
self.home_dir = dct['init_child_result']['home_dir']
def _connect(self):
"""
Establish a connection to the master process's UNIX listener socket,
constructing a mitogen.master.Router to communicate with the master,
and a mitogen.parent.Context to represent it.
Depending on the original transport we should emulate, trigger one of
the _connect_*() service calls defined above to cause the master
process to establish the real connection on our behalf, or return a
reference to the existing one.
"""
if self.connected:
return
self._connect_broker()
stack = self._build_stack()
self._connect_stack(stack)
def close(self, new_task=False):
"""
Arrange for the mitogen.master.Router running in the worker to
gracefully shut down, and wait for shutdown to complete. Safe to call
multiple times.
"""
if self.context:
self.parent.call_service(
service_name='ansible_mitogen.services.ContextService',
method_name='put',
context=self.context
)
self.context = None
self.fork_context = None
self.login_context = None
if self.broker and not new_task:
self.broker.shutdown()
self.broker.join()
self.broker = None
self.router = None
def call_async(self, func, *args, **kwargs):
"""
Start a function call to the target.
:param bool use_login_context:
If present and :data:`True`, send the call to the login account
context rather than the optional become user context.
:returns:
mitogen.core.Receiver that receives the function call result.
"""
self._connect()
if kwargs.pop('use_login_context', None):
call_context = self.login_context
else:
call_context = self.context
return call_context.call_async(func, *args, **kwargs)
def call(self, func, *args, **kwargs):
"""
Start and wait for completion of a function call in the target.
:raises mitogen.core.CallError:
The function call failed.
:returns:
Function return value.
"""
t0 = time.time()
try:
return self.call_async(func, *args, **kwargs).get().unpickle()
finally:
LOG.debug('Call took %d ms: %r', 1000 * (time.time() - t0),
mitogen.parent.CallSpec(func, args, kwargs))
def create_fork_child(self):
"""
Fork a new child off the target context. The actual fork occurs from
the 'virginal fork parent', which does not any Ansible modules prior to
fork, to avoid conflicts resulting from custom module_utils paths.
:returns:
mitogen.core.Context of the new child.
"""
return self.call(ansible_mitogen.target.create_fork_child)
def get_default_cwd(self):
"""
Overridden by connections/mitogen_local.py to emulate behaviour of CWD
being fixed to that of ActionBase._loader.get_basedir().
"""
return None
def get_default_env(self):
"""
Overridden by connections/mitogen_local.py to emulate behaviour of
WorkProcess environment inherited from WorkerProcess.
"""
return None
def exec_command(self, cmd, in_data='', sudoable=True, mitogen_chdir=None):
"""
Implement exec_command() by calling the corresponding
ansible_mitogen.target function in the target.
:param str cmd:
Shell command to execute.
:param bytes in_data:
Data to supply on ``stdin`` of the process.
:returns:
(return code, stdout bytes, stderr bytes)
"""
emulate_tty = (not in_data and sudoable)
rc, stdout, stderr = self.call(
ansible_mitogen.target.exec_command,
cmd=mitogen.utils.cast(cmd),
in_data=mitogen.utils.cast(in_data),
chdir=mitogen_chdir or self.get_default_cwd(),
emulate_tty=emulate_tty,
)
stderr += 'Shared connection to %s closed.%s' % (
self._play_context.remote_addr,
('\r\n' if emulate_tty else '\n'),
)
return rc, stdout, stderr
def fetch_file(self, in_path, out_path):
"""
Implement fetch_file() by calling the corresponding
ansible_mitogen.target function in the target.
:param str in_path:
Remote filesystem path to read.
:param str out_path:
Local filesystem path to write.
"""
output = self.call(ansible_mitogen.target.read_path,
mitogen.utils.cast(in_path))
ansible_mitogen.target.write_path(out_path, output)
def put_data(self, out_path, data, mode=None, utimes=None):
"""
Implement put_file() by caling the corresponding
ansible_mitogen.target function in the target.
:param str out_path:
Remote filesystem path to write.
:param byte data:
File contents to put.
"""
self.call(ansible_mitogen.target.write_path,
mitogen.utils.cast(out_path),
mitogen.core.Blob(data),
mode=mode,
utimes=utimes)
def put_file(self, in_path, out_path):
"""
Implement put_file() by streamily transferring the file via
FileService.
:param str in_path:
Local filesystem path to read.
:param str out_path:
Remote filesystem path to write.
"""
st = os.stat(in_path)
if not stat.S_ISREG(st.st_mode):
raise IOError('%r is not a regular file.' % (in_path,))
# If the file is sufficiently small, just ship it in the argument list
# rather than introducing an extra RTT for the child to request it from
# FileService.
if st.st_size <= 32768:
fp = open(in_path, 'rb')
try:
s = fp.read(32769)
finally:
fp.close()
# Ensure file was not growing during call.
if len(s) == st.st_size:
return self.put_data(out_path, s, mode=st.st_mode,
utimes=(st.st_atime, st.st_mtime))
self.parent.call_service(
service_name='mitogen.service.FileService',
method_name='register',
path=mitogen.utils.cast(in_path)
)
self.call(
ansible_mitogen.target.transfer_file,
context=self.parent,
in_path=in_path,
out_path=out_path
)