# (c) 2016 Red Hat Inc. # (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: Ansible Networking Team connection: network_cli short_description: Use network_cli to run command on network appliances description: - This connection plugin provides a connection to remote devices over the SSH and implements a CLI shell. This connection plugin is typically used by network devices for sending and receiving CLi commands to network devices. version_added: "2.3" options: host: description: - Specifies the remote device FQDN or IP address to establish the SSH connection to. default: inventory_hostname vars: - name: ansible_host port: type: int description: - Specifies the port on the remote device to listening for connections when establishing the SSH connection. default: 22 ini: - section: defaults key: remote_port env: - name: ANSIBLE_REMOTE_PORT vars: - name: ansible_port network_os: description: - Configures the device platform network operating system. This value is used to load the correct terminal and cliconf plugins to communicate with the remote device vars: - name: ansible_network_os remote_user: description: - The username used to authenticate to the remote device when the SSH connection is first established. If the remote_user is not specified, the connection will use the username of the logged in user. - Can be configured form the CLI via the C(--user) or C(-u) options ini: - section: defaults key: remote_user env: - name: ANSIBLE_REMOTE_USER vars: - name: ansible_user password: description: - Configures the user password used to authenticate to the remote device when first establishing the SSH connection. vars: - name: ansible_pass private_key_file: description: - The private SSH key or certificate file used to to authenticate to the remote device when first establishing the SSH connection. ini: section: defaults key: private_key_file env: - name: ANSIBLE_PRIVATE_KEY_FILE vars: - name: ansible_private_key_file timeout: type: int description: - Sets the connection time, in seconds, for the communicating with the remote device. This timeout is used as the default timeout value for commands when issuing a command to the network CLI. If the command does not return in timeout seconds, the an error is generated. default: 120 become: type: boolean description: - The become option will instruct the CLI session to attempt privilege escalation on platforms that support it. Normally this means transitioning from user mode to C(enable) mode in the CLI session. If become is set to True and the remote device does not support privilege escalation or the privilege has already been elevated, then this option is silently ignored - Can be configured form the CLI via the C(--become) or C(-b) options default: False ini: section: privilege_escalation key: become env: - name: ANSIBLE_BECOME vars: - name: ansible_become become_method: description: - This option allows the become method to be specified in for handling privilege escalation. Typically the become_method value is set to C(enable) but could be defined as other values. default: sudo ini: section: privilege_escalation key: become_method env: - name: ANSIBLE_BECOME_METHOD vars: - name: ansible_become_method host_key_auto_add: type: boolean description: - By default, Ansible will prompt the user before adding SSH keys to the known hosts file. Since persistent connections such as network_cli run in background processes, the user will never be prompted. By enabling this option, unknown host keys will automatically be added to the known hosts file. - Be sure to fully understand the security implications of enabling this option on production systems as it could create a security vulnerability. default: False ini: section: paramiko_connection key: host_key_auto_add env: - name: ANSIBLE_HOST_KEY_AUTO_ADD persistent_connect_timeout: type: int description: - Configures, in seconds, the amount of time to wait when trying to initially establish a persistent connection. If this value expires before the connection to the remote device is completed, the connection will fail default: 30 ini: section: persistent_connection key: persistent_connect_timeout env: - name: ANSIBLE_PERSISTENT_CONNECT_TIMEOUT persistent_command_timeout: type: int description: - Configures, in seconds, the amount of time to wait for a command to return from the remote device. If this timer is exceeded before the command returns, the connection plugin will raise an exception and close default: 10 ini: section: persistent_connection key: persistent_command_timeout env: - name: ANSIBLE_PERSISTENT_COMMAND_TIMEOUT """ import json import logging import re import os import socket import traceback from ansible import constants as C from ansible.errors import AnsibleConnectionFailure from ansible.module_utils.six import BytesIO, PY3 from ansible.module_utils.six.moves import cPickle from ansible.module_utils._text import to_bytes, to_text from ansible.playbook.play_context import PlayContext from ansible.plugins.loader import cliconf_loader, terminal_loader, connection_loader from ansible.plugins.connection import ConnectionBase from ansible.utils.path import unfrackpath try: from __main__ import display except ImportError: from ansible.utils.display import Display display = Display() class Connection(ConnectionBase): ''' CLI (shell) SSH connections on Paramiko ''' transport = 'network_cli' has_pipelining = True force_persistence = True def __init__(self, play_context, new_stdin, *args, **kwargs): super(Connection, self).__init__(play_context, new_stdin, *args, **kwargs) self._ssh_shell = None self._matched_prompt = None self._matched_pattern = None self._last_response = None self._history = list() self._play_context = play_context self._local = connection_loader.get('local', play_context, '/dev/null') self._local.set_options() self._terminal = None self._cliconf = None self._ansible_playbook_pid = kwargs.get('ansible_playbook_pid') if self._play_context.verbosity > 3: logging.getLogger('paramiko').setLevel(logging.DEBUG) # reconstruct the socket_path and set instance values accordingly self._update_connection_state() def __getattr__(self, name): try: return self.__dict__[name] except KeyError: if name.startswith('_'): raise AttributeError("'%s' object has no attribute '%s'" % (self.__class__.__name__, name)) return getattr(self._cliconf, name) def get_prompt(self): """Returns the current prompt from the device""" return self._matched_prompt def exec_command(self, cmd, in_data=None, sudoable=True): # this try..except block is just to handle the transition to supporting # network_cli as a toplevel connection. Once connection=local is gone, # this block can be removed as well and all calls passed directly to # the local connection if self._ssh_shell: try: cmd = json.loads(to_text(cmd, errors='surrogate_or_strict')) kwargs = {'command': to_bytes(cmd['command'], errors='surrogate_or_strict')} for key in ('prompt', 'answer', 'sendonly', 'newline', 'prompt_retry_check'): if cmd.get(key) is True or cmd.get(key) is False: kwargs[key] = cmd[key] elif cmd.get(key) is not None: kwargs[key] = to_bytes(cmd[key], errors='surrogate_or_strict') return self.send(**kwargs) except ValueError: cmd = to_bytes(cmd, errors='surrogate_or_strict') return self.send(command=cmd) else: return self._local.exec_command(cmd, in_data, sudoable) def put_file(self, in_path, out_path): return self._local.put_file(in_path, out_path) def fetch_file(self, in_path, out_path): return self._local.fetch_file(in_path, out_path) def update_play_context(self, pc_data): """Updates the play context information for the connection""" pc_data = to_bytes(pc_data) if PY3: pc_data = cPickle.loads(pc_data, encoding='bytes') else: pc_data = cPickle.loads(pc_data) play_context = PlayContext() play_context.deserialize(pc_data) messages = ['updating play_context for connection'] if self._play_context.become is False and play_context.become is True: auth_pass = play_context.become_pass self._terminal.on_become(passwd=auth_pass) messages.append('authorizing connection') elif self._play_context.become is True and not play_context.become: self._terminal.on_unbecome() messages.append('deauthorizing connection') self._play_context = play_context return messages def _connect(self): ''' Connects to the remote device and starts the terminal ''' if self.connected: return self.paramiko_conn = connection_loader.get('paramiko', self._play_context, '/dev/null') self.paramiko_conn.set_options(direct={'look_for_keys': not bool(self._play_context.password and not self._play_context.private_key_file)}) self.paramiko_conn.force_persistence = self.force_persistence ssh = self.paramiko_conn._connect() display.vvvv('ssh connection done, setting terminal', host=self._play_context.remote_addr) self._ssh_shell = ssh.ssh.invoke_shell() self._ssh_shell.settimeout(self._play_context.timeout) network_os = self._play_context.network_os if not network_os: raise AnsibleConnectionFailure( 'Unable to automatically determine host network os. Please ' 'manually configure ansible_network_os value for this host' ) self._terminal = terminal_loader.get(network_os, self) if not self._terminal: raise AnsibleConnectionFailure('network os %s is not supported' % network_os) display.vvvv('loaded terminal plugin for network_os %s' % network_os, host=self._play_context.remote_addr) self._cliconf = cliconf_loader.get(network_os, self) if self._cliconf: display.vvvv('loaded cliconf plugin for network_os %s' % network_os, host=self._play_context.remote_addr) else: display.vvvv('unable to load cliconf for network_os %s' % network_os) self.receive() display.vvvv('firing event: on_open_shell()', host=self._play_context.remote_addr) self._terminal.on_open_shell() if self._play_context.become and self._play_context.become_method == 'enable': display.vvvv('firing event: on_become', host=self._play_context.remote_addr) auth_pass = self._play_context.become_pass self._terminal.on_become(passwd=auth_pass) display.vvvv('ssh connection has completed successfully', host=self._play_context.remote_addr) self._connected = True return self def _update_connection_state(self): ''' Reconstruct the connection socket_path and check if it exists If the socket path exists then the connection is active and set both the _socket_path value to the path and the _connected value to True. If the socket path doesn't exist, leave the socket path value to None and the _connected value to False ''' ssh = connection_loader.get('ssh', class_only=True) cp = ssh._create_control_path(self._play_context.remote_addr, self._play_context.port, self._play_context.remote_user, self._play_context.connection, self._ansible_playbook_pid) tmp_path = unfrackpath(C.PERSISTENT_CONTROL_PATH_DIR) socket_path = unfrackpath(cp % dict(directory=tmp_path)) if os.path.exists(socket_path): self._connected = True self._socket_path = socket_path def reset(self): ''' Reset the connection ''' if self._socket_path: display.vvvv('resetting persistent connection for socket_path %s' % self._socket_path, host=self._play_context.remote_addr) self.close() display.vvvv('reset call on connection instance', host=self._play_context.remote_addr) def close(self): ''' Close the active connection to the device ''' # only close the connection if its connected. if self._connected: display.debug("closing ssh connection to device") if self._ssh_shell: display.debug("firing event: on_close_shell()") self._terminal.on_close_shell() self._ssh_shell.close() self._ssh_shell = None display.debug("cli session is now closed") self._connected = False display.debug("ssh connection has been closed successfully") def receive(self, command=None, prompts=None, answer=None, newline=True, prompt_retry_check=False): ''' Handles receiving of output from command ''' recv = BytesIO() handled = False self._matched_prompt = None self._matched_cmd_prompt = None matched_prompt_window = window_count = 0 while True: data = self._ssh_shell.recv(256) # when a channel stream is closed, received data will be empty if not data: break recv.write(data) offset = recv.tell() - 256 if recv.tell() > 256 else 0 recv.seek(offset) window = self._strip(recv.read()) window_count += 1 if prompts and not handled: handled = self._handle_prompt(window, prompts, answer, newline) matched_prompt_window = window_count elif prompts and handled and prompt_retry_check and matched_prompt_window + 1 == window_count: # check again even when handled, if same prompt repeats in next window # (like in the case of a wrong enable password, etc) indicates # value of answer is wrong, report this as error. if self._handle_prompt(window, prompts, answer, newline, prompt_retry_check): raise AnsibleConnectionFailure("For matched prompt '%s', answer is not valid" % self._matched_cmd_prompt) if self._find_prompt(window): self._last_response = recv.getvalue() resp = self._strip(self._last_response) return self._sanitize(resp, command) def send(self, command, prompt=None, answer=None, newline=True, sendonly=False, prompt_retry_check=False): ''' Sends the command to the device in the opened shell ''' try: self._history.append(command) self._ssh_shell.sendall(b'%s\r' % command) if sendonly: return response = self.receive(command, prompt, answer, newline, prompt_retry_check) return to_text(response, errors='surrogate_or_strict') except (socket.timeout, AttributeError): display.vvvv(traceback.format_exc(), host=self._play_context.remote_addr) raise AnsibleConnectionFailure("timeout trying to send command: %s" % command.strip()) def _strip(self, data): ''' Removes ANSI codes from device response ''' for regex in self._terminal.ansi_re: data = regex.sub(b'', data) return data def _handle_prompt(self, resp, prompts, answer, newline, prompt_retry_check=False): ''' Matches the command prompt and responds :arg resp: Byte string containing the raw response from the remote :arg prompts: Sequence of byte strings that we consider prompts for input :arg answer: Byte string to send back to the remote if we find a prompt. A carriage return is automatically appended to this string. :returns: True if a prompt was found in ``resp``. False otherwise ''' if not isinstance(prompts, list): prompts = [prompts] prompts = [re.compile(r, re.I) for r in prompts] for regex in prompts: match = regex.search(resp) if match: # if prompt_retry_check is enabled to check if same prompt is # repeated don't send answer again. if not prompt_retry_check: self._ssh_shell.sendall(b'%s' % answer) if newline: self._ssh_shell.sendall(b'\r') self._matched_cmd_prompt = match.group() return True return False def _sanitize(self, resp, command=None): ''' Removes elements from the response before returning to the caller ''' cleaned = [] for line in resp.splitlines(): if (command and line.strip() == command.strip()) or self._matched_prompt.strip() in line: continue cleaned.append(line) return b'\n'.join(cleaned).strip() def _find_prompt(self, response): '''Searches the buffered response for a matching command prompt ''' errored_response = None is_error_message = False for regex in self._terminal.terminal_stderr_re: if regex.search(response): is_error_message = True # Check if error response ends with command prompt if not # receive it buffered prompt for regex in self._terminal.terminal_stdout_re: match = regex.search(response) if match: errored_response = response self._matched_pattern = regex.pattern self._matched_prompt = match.group() break if not is_error_message: for regex in self._terminal.terminal_stdout_re: match = regex.search(response) if match: self._matched_pattern = regex.pattern self._matched_prompt = match.group() if not errored_response: return True if errored_response: raise AnsibleConnectionFailure(errored_response) return False