# coding=utf-8
# Copyright 2014 International Business Machines Corporation
# All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
"""
Ironic console utilities.
"""
import errno
import fcntl
import ipaddress
import os
import signal
import socket
import subprocess
import time
from oslo_concurrency import lockutils
from oslo_log import log as logging
from oslo_service import loopingcall
from oslo_utils import fileutils
import psutil
from ironic.common import exception
from ironic.common.i18n import _
from ironic.common import utils
from ironic.conf import CONF
LOG = logging.getLogger(__name__)
ALLOCATED_PORTS = set() # in-memory set of already allocated ports
SERIAL_LOCK = 'ironic-console-lock'
def _get_console_pid_dir():
"""Return the directory for the pid file."""
return CONF.console.terminal_pid_dir or CONF.tempdir
def _ensure_console_pid_dir_exists():
"""Ensure that the console PID directory exists
Checks that the directory for the console PID file exists
and if not, creates it.
:raises: ConsoleError if the directory doesn't exist and cannot be created
"""
dir = _get_console_pid_dir()
if not os.path.exists(dir):
try:
os.makedirs(dir)
except OSError as exc:
msg = (_("Cannot create directory '%(path)s' for console PID file."
" Reason: %(reason)s.") % {'path': dir, 'reason': exc})
LOG.error(msg)
raise exception.ConsoleError(message=msg)
def _get_console_pid_file(node_uuid):
"""Generate the pid file name to hold the terminal process id."""
pid_dir = _get_console_pid_dir()
name = "%s.pid" % node_uuid
path = os.path.join(pid_dir, name)
return path
def _get_console_pid(node_uuid):
"""Get the terminal process id from pid file."""
pid_path = _get_console_pid_file(node_uuid)
try:
with open(pid_path, 'r') as f:
pid_str = f.readline()
return int(pid_str)
except (IOError, ValueError, FileNotFoundError):
raise exception.NoConsolePid(pid_path=pid_path)
def _stop_console(node_uuid):
"""Close the serial console for a node
Kills the console process and deletes the PID file.
:param node_uuid: the UUID of the node
:raises: NoConsolePid if no console PID was found
:raises: ConsoleError if unable to stop the console process
"""
try:
console_pid = _get_console_pid(node_uuid)
os.kill(console_pid, signal.SIGTERM)
# make sure the process gets killed hard if required
attempt = 0
max_attempts = CONF.console.kill_timeout // 0.2
while attempt < max_attempts:
if psutil.pid_exists(console_pid):
if attempt == max_attempts - 1:
os.kill(console_pid, signal.SIGKILL)
LOG.debug("Waiting for the console process with PID %(pid)s "
"to exit. Node: %(node)s.",
{'pid': console_pid, 'node': node_uuid})
time.sleep(0.2)
attempt += 1
else:
break
except OSError as exc:
if exc.errno != errno.ESRCH:
msg = (_("Could not stop the console for node '%(node)s'. "
"Reason: %(err)s.") % {'node': node_uuid, 'err': exc})
raise exception.ConsoleError(message=msg)
else:
LOG.warning("Console process for node %s is not running "
"but pid file exists.", node_uuid)
finally:
utils.unlink_without_raise(_get_console_pid_file(node_uuid))
[docs]
def make_persistent_password_file(path, password):
"""Writes a file containing a password until deleted."""
try:
fileutils.delete_if_exists(path)
with open(path, 'wb') as file:
os.chmod(path, 0o600)
file.write(password.encode())
return path
except Exception as e:
fileutils.delete_if_exists(path)
raise exception.PasswordFileFailedToCreate(error=e)
def _get_port_range():
config_range = CONF.console.port_range
start, stop = map(int, config_range.split(':'))
if start >= stop:
msg = _("[console]port_range should be in the "
"format <start>:<stop> and start < stop")
raise exception.InvalidParameterValue(msg)
return start, stop
def _verify_port(port, host=None):
"""Check whether specified port is in use."""
ip_version = None
if host is not None:
try:
ip_version = ipaddress.ip_address(host).version
except ValueError:
# Assume it's a hostname
pass
else:
host = CONF.host
if ip_version == 6:
s = socket.socket(socket.AF_INET6)
else:
s = socket.socket()
try:
s.bind((host, port))
except socket.error:
raise exception.Conflict()
finally:
s.close()
[docs]
@lockutils.synchronized(SERIAL_LOCK)
def acquire_port(host=None):
"""Returns a free TCP port on current host.
Find and returns a free TCP port in the range
of 'CONF.console.port_range'.
"""
start, stop = _get_port_range()
for port in range(start, stop):
if port in ALLOCATED_PORTS:
continue
try:
_verify_port(port, host=host)
ALLOCATED_PORTS.add(port)
return port
except exception.Conflict:
pass
raise exception.NoFreeIPMITerminalPorts(host=CONF.host)
[docs]
@lockutils.synchronized(SERIAL_LOCK)
def release_port(port):
"""Release specified TCP port."""
ALLOCATED_PORTS.discard(port)
[docs]
def get_shellinabox_console_url(port):
"""Get a url to access the console via shellinaboxd.
:param port: the terminal port for the node.
"""
console_host = utils.wrap_ipv6(CONF.my_ip)
scheme = 'https' if CONF.console.terminal_cert_dir else 'http'
return '%(scheme)s://%(host)s:%(port)s' % {'scheme': scheme,
'host': console_host,
'port': port}
class _PopenNonblockingPipe(object):
def __init__(self, source):
self._source = source
self._output = b''
self._wait = False
self._finished = False
self._set_async()
def _set_async(self):
flags = fcntl.fcntl(self._source, fcntl.F_GETFL)
fcntl.fcntl(self._source, fcntl.F_SETFL, flags | os.O_NONBLOCK)
def read(self, num_bytes=4096):
if self._finished:
return
try:
if self._wait:
time.sleep(1)
self._wait = False
data = os.read(self._source.fileno(), num_bytes)
self._output += data
if len(data) < num_bytes:
self._wait = True
except OSError:
self._finished = True
@property
def output(self):
return self._output
@property
def finished(self):
return self._finished
[docs]
def start_shellinabox_console(node_uuid, port, console_cmd,
env_variables=None):
"""Open the serial console for a node.
:param node_uuid: the uuid for the node.
:param port: the terminal port for the node.
:param console_cmd: the shell command that gets the console.
:param env_variables: optional dict of environment variables to pass to
the subprocess (e.g. IPMI_PASSWORD for ipmitool -E).
:raises: ConsoleError if the directory for the PID file cannot be created
or an old process cannot be stopped.
:raises: ConsoleSubprocessFailed when invoking the subprocess failed.
"""
# make sure that the old console for this node is stopped
# and the files are cleared
try:
_stop_console(node_uuid)
except exception.NoConsolePid:
pass
_ensure_console_pid_dir_exists()
pid_file = _get_console_pid_file(node_uuid)
# put together the command and arguments for invoking the console
args = []
args.append(CONF.console.terminal)
if CONF.console.terminal_cert_dir:
args.append("-c")
args.append(CONF.console.terminal_cert_dir)
else:
args.append("-t")
args.append("-p")
args.append(str(port))
args.append("--background=%s" % pid_file)
args.append("-s")
args.append(console_cmd)
# run the command as a subprocess
try:
LOG.debug('Running subprocess: %s', ' '.join(args))
# use pipe here to catch the error in case shellinaboxd
# failed to start.
popen_kwargs = {'stdout': subprocess.PIPE, 'stderr': subprocess.PIPE}
if env_variables is not None:
popen_kwargs['env'] = dict(os.environ, **env_variables)
obj = subprocess.Popen(args, **popen_kwargs)
except (OSError, ValueError) as e:
error = _("%(exec_error)s\n"
"Command: %(command)s") % {'exec_error': str(e),
'command': ' '.join(args)}
LOG.warning(error)
raise exception.ConsoleSubprocessFailed(error=error)
error_message = _(
"Timeout or error while waiting for console subprocess to start for "
"node: %(node)s.\nCommand: %(command)s.\n") % {
'node': node_uuid,
'command': ' '.join(args)}
stdout_pipe, stderr_pipe = (
_PopenNonblockingPipe(obj.stdout), _PopenNonblockingPipe(obj.stderr))
def _wait(node_uuid, popen_obj):
locals['returncode'] = popen_obj.poll()
# check if the console pid is created and the process is running.
# if it is, then the shellinaboxd is invoked successfully as a daemon.
# otherwise check the error.
if (locals['returncode'] == 0 and os.path.exists(pid_file)
and psutil.pid_exists(_get_console_pid(node_uuid))):
raise loopingcall.LoopingCallDone()
if locals['returncode'] is not None:
watched = (stdout_pipe, stderr_pipe)
while time.time() < expiration and not all(
(i.finished for i in watched)):
for pipe in watched:
pipe.read()
locals['errstr'] = error_message + _(
"Exit code: %(return_code)s.\nStdout: %(stdout)r\n"
"Stderr: %(stderr)r") % {
'return_code': locals['returncode'],
'stdout': stdout_pipe.output, 'stderr': stderr_pipe.output}
raise loopingcall.LoopingCallDone()
if time.time() > expiration:
locals['errstr'] = error_message
raise loopingcall.LoopingCallDone()
locals = {'returncode': None, 'errstr': ''}
expiration = time.time() + CONF.console.subprocess_timeout
timer = loopingcall.FixedIntervalLoopingCall(_wait, node_uuid, obj)
timer.start(interval=CONF.console.subprocess_checking_interval).wait()
if locals['errstr']:
LOG.warning(locals['errstr'])
raise exception.ConsoleSubprocessFailed(error=locals['errstr'])
[docs]
def stop_shellinabox_console(node_uuid):
"""Close the serial console for a node.
:param node_uuid: the UUID of the node
:raises: ConsoleError if unable to stop the console process
"""
try:
_stop_console(node_uuid)
except exception.NoConsolePid:
LOG.warning("No console pid found for node %s while trying to "
"stop shellinabox console.", node_uuid)
[docs]
def get_socat_console_url(port):
"""Get a URL to access the console via socat.
:param port: the terminal port (integer) for the node
:return: an access URL to the socat console of the node
"""
console_host = utils.wrap_ipv6(CONF.console.socat_address)
return 'tcp://%(host)s:%(port)s' % {'host': console_host,
'port': port}
_SOCAT_METACHARACTERS = frozenset(',:!\'"()[]{}\\')
def _escape_socat_console_cmd(console_cmd):
"""Escape socat's metacharacters in an ``EXEC:`` command line.
socat lexes the command line twice, once when parsing the address
specification and again when splitting the ``EXEC:`` command line into
arguments, and each pass consumes one level of escaping. Spaces are left
alone, since they are what the second pass separates arguments at. No
shell is involved anywhere.
Address syntax (separators, quoting, nesting and escaping):
http://www.dest-unreach.org/socat/doc/socat.html#ADDRESS_SPECIFICATIONS
``EXEC:``, whose arguments are separated by single spaces:
http://www.dest-unreach.org/socat/doc/socat.html#ADDRESS_EXEC
:param console_cmd: the command line for socat to execute
:return: the command line with socat's metacharacters escaped
"""
return ''.join('\\' * 3 + char if char in _SOCAT_METACHARACTERS else char
for char in console_cmd)
[docs]
def start_socat_console(node_uuid, port, console_cmd, env_variables=None):
"""Open the serial console for a node.
:param node_uuid: the uuid of the node
:param port: the terminal port for the node
:param console_cmd: the command that will be executed by socat to
establish console to the node. Arguments are separated by single
spaces; socat runs the command directly, without a shell.
:param env_variables: optional dict of environment variables to pass to
the subprocess (e.g. IPMI_PASSWORD for ipmitool -E).
:raises ConsoleError: if the directory for the PID file or the PID file
cannot be created
:raises ConsoleSubprocessFailed: when invoking the subprocess failed
"""
# Make sure that the old console for this node is stopped.
# If no console is running, we may get exception NoConsolePid.
try:
_stop_console(node_uuid)
except exception.NoConsolePid:
pass
_ensure_console_pid_dir_exists()
pid_file = _get_console_pid_file(node_uuid)
# put together the command and arguments for invoking the console
args = ['socat']
# set timeout check for user's connection. If the timeout value
# is not 0, after timeout seconds of inactivity on the client side,
# the connection will be closed.
if CONF.console.terminal_timeout > 0:
args.append('-T%d' % CONF.console.terminal_timeout)
args.append('-L%s' % pid_file)
console_host = CONF.console.socat_address
if ipaddress.ip_address(console_host).version == 6:
arg = ('TCP6-LISTEN:%(port)s,bind=[%(host)s],reuseaddr,fork,'
'max-children=1')
else:
arg = ('TCP4-LISTEN:%(port)s,bind=%(host)s,reuseaddr,fork,'
'max-children=1')
args.append(arg % {'host': console_host,
'port': port})
escaped_cmd = _escape_socat_console_cmd(console_cmd)
args.append('EXEC:"%s",pty,stderr' % escaped_cmd)
# run the command as a subprocess
try:
LOG.debug('Running subprocess: %s', ' '.join(args))
# Use pipe here to catch the error in case socat
# fails to start. Note that socat uses stdout as transferring
# data, so we only capture stderr for checking if it fails.
popen_kwargs = {'stderr': subprocess.PIPE}
if env_variables is not None:
popen_kwargs['env'] = dict(os.environ, **env_variables)
obj = subprocess.Popen(args, **popen_kwargs)
except (OSError, ValueError) as e:
error = _("%(exec_error)s\n"
"Command: %(command)s") % {'exec_error': str(e),
'command': ' '.join(args)}
LOG.exception('Unable to start socat console')
raise exception.ConsoleSubprocessFailed(error=error)
# NOTE: we need to check if socat fails to start here.
# If it starts successfully, it will run in non-daemon mode and
# will not return until the console session is stopped.
def _wait(node_uuid, popen_obj):
wait_state['returncode'] = popen_obj.poll()
# socat runs in non-daemon mode, so it should not return now
if wait_state['returncode'] is None:
# If the pid file is created and the process is running,
# we stop checking it periodically.
if (os.path.exists(pid_file)
and psutil.pid_exists(_get_console_pid(node_uuid))):
raise loopingcall.LoopingCallDone()
else:
# socat returned, it failed to start.
# We get the error (out should be None in this case).
(_out, err) = popen_obj.communicate()
wait_state['errstr'] = _(
"Command: %(command)s.\n"
"Exit code: %(return_code)s.\n"
"Stderr: %(error)r") % {
'command': ' '.join(args),
'return_code': wait_state['returncode'],
'error': err}
LOG.error(wait_state['errstr'])
raise loopingcall.LoopingCallDone()
if time.time() > expiration:
wait_state['errstr'] = (_("Timeout while waiting for console "
"subprocess to start for node %s.") %
node_uuid)
LOG.error(wait_state['errstr'])
raise loopingcall.LoopingCallDone()
wait_state = {'returncode': None, 'errstr': ''}
expiration = time.time() + CONF.console.subprocess_timeout
timer = loopingcall.FixedIntervalLoopingCall(_wait, node_uuid, obj)
timer.start(interval=CONF.console.subprocess_checking_interval).wait()
if wait_state['errstr']:
raise exception.ConsoleSubprocessFailed(error=wait_state['errstr'])
[docs]
def stop_socat_console(node_uuid):
"""Close the serial console for a node.
:param node_uuid: the UUID of the node
:raise ConsoleError: if unable to stop the console process
"""
try:
_stop_console(node_uuid)
except exception.NoConsolePid:
LOG.warning("No console pid found for node %s while trying to "
"stop socat console.", node_uuid)
