community.general/lib/ansible/plugins/connections/ssh.py

501 lines
20 KiB
Python

# (c) 2012, Michael DeHaan <michael.dehaan@gmail.com>
#
# This file is part of Ansible
#
# Ansible is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Ansible is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Ansible. If not, see <http://www.gnu.org/licenses/>.
#
from __future__ import (absolute_import, division, print_function)
__metaclass__ = type
import gettext
import fcntl
import hmac
import os
import pipes
import pty
import pwd
import random
import re
import select
import shlex
import subprocess
import time
from hashlib import sha1
from ansible import constants as C
from ansible.errors import AnsibleError, AnsibleConnectionFailure, AnsibleFileNotFound
from ansible.plugins.connections import ConnectionBase
from ansible.utils.debug import debug
class Connection(ConnectionBase):
''' ssh based connections '''
become_methods = frozenset(C.BECOME_METHODS).difference(['runas'])
def __init__(self, *args, **kwargs):
# SSH connection specific init stuff
self._common_args = []
self.HASHED_KEY_MAGIC = "|1|"
self._has_pipelining = True
# FIXME: move the lockfile locations to ActionBase?
#fcntl.lockf(self.runner.process_lockfile, fcntl.LOCK_EX)
#self.cp_dir = utils.prepare_writeable_dir('$HOME/.ansible/cp',mode=0700)
self._cp_dir = '/tmp'
#fcntl.lockf(self.runner.process_lockfile, fcntl.LOCK_UN)
super(Connection, self).__init__(*args, **kwargs)
# FIXME: make this work, should be set from connection info
self._ipv6 = False
self.host = self._connection_info.remote_addr
if self._ipv6:
self.host = '[%s]' % self.host
@property
def transport(self):
''' used to identify this connection object from other classes '''
return 'ssh'
def _connect(self):
''' connect to the remote host '''
self._display.vvv("ESTABLISH SSH CONNECTION FOR USER: {0}".format(self._connection_info.remote_user), host=self._connection_info.remote_addr)
if self._connected:
return self
extra_args = C.ANSIBLE_SSH_ARGS
if extra_args is not None:
# make sure there is no empty string added as this can produce weird errors
self._common_args += [x.strip() for x in shlex.split(extra_args) if x.strip()]
else:
self._common_args += (
"-o", "ControlMaster=auto",
"-o", "ControlPersist=60s",
"-o", "ControlPath=\"{0}\"".format(C.ANSIBLE_SSH_CONTROL_PATH % dict(directory=self._cp_dir)),
)
cp_in_use = False
cp_path_set = False
for arg in self._common_args:
if "ControlPersist" in arg:
cp_in_use = True
if "ControlPath" in arg:
cp_path_set = True
if cp_in_use and not cp_path_set:
self._common_args += ("-o", "ControlPath=\"{0}\"".format(
C.ANSIBLE_SSH_CONTROL_PATH % dict(directory=self._cp_dir))
)
if not C.HOST_KEY_CHECKING:
self._common_args += ("-o", "StrictHostKeyChecking=no")
if self._connection_info.port is not None:
self._common_args += ("-o", "Port={0}".format(self._connection_info.port))
if self._connection_info.private_key_file is not None:
self._common_args += ("-o", "IdentityFile=\"{0}\"".format(os.path.expanduser(self._connection_info.private_key_file)))
if self._connection_info.password:
self._common_args += ("-o", "GSSAPIAuthentication=no",
"-o", "PubkeyAuthentication=no")
else:
self._common_args += ("-o", "KbdInteractiveAuthentication=no",
"-o", "PreferredAuthentications=gssapi-with-mic,gssapi-keyex,hostbased,publickey",
"-o", "PasswordAuthentication=no")
if self._connection_info.remote_user is not None and self._connection_info.remote_user != pwd.getpwuid(os.geteuid())[0]:
self._common_args += ("-o", "User={0}".format(self._connection_info.remote_user))
self._common_args += ("-o", "ConnectTimeout={0}".format(self._connection_info.timeout))
self._connected = True
return self
def _run(self, cmd, indata):
if indata:
# do not use pseudo-pty
p = subprocess.Popen(cmd, stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
stdin = p.stdin
else:
# try to use upseudo-pty
try:
# Make sure stdin is a proper (pseudo) pty to avoid: tcgetattr errors
master, slave = pty.openpty()
p = subprocess.Popen(cmd, stdin=slave, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
stdin = os.fdopen(master, 'w', 0)
os.close(slave)
except:
p = subprocess.Popen(cmd, stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
stdin = p.stdin
return (p, stdin)
def _password_cmd(self):
if self._connection_info.password:
try:
p = subprocess.Popen(["sshpass"], stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
p.communicate()
except OSError:
raise AnsibleError("to use the 'ssh' connection type with passwords, you must install the sshpass program")
(self.rfd, self.wfd) = os.pipe()
return ["sshpass", "-d{0}".format(self.rfd)]
return []
def _send_password(self):
if self._connection_info.password:
os.close(self.rfd)
os.write(self.wfd, "{0}\n".format(self._connection_info.password))
os.close(self.wfd)
def _communicate(self, p, stdin, indata, sudoable=True):
fcntl.fcntl(p.stdout, fcntl.F_SETFL, fcntl.fcntl(p.stdout, fcntl.F_GETFL) & ~os.O_NONBLOCK)
fcntl.fcntl(p.stderr, fcntl.F_SETFL, fcntl.fcntl(p.stderr, fcntl.F_GETFL) & ~os.O_NONBLOCK)
# We can't use p.communicate here because the ControlMaster may have stdout open as well
stdout = ''
stderr = ''
rpipes = [p.stdout, p.stderr]
if indata:
try:
stdin.write(indata)
stdin.close()
except:
raise AnsibleConnectionFailure('SSH Error: data could not be sent to the remote host. Make sure this host can be reached over ssh')
# Read stdout/stderr from process
while True:
rfd, wfd, efd = select.select(rpipes, [], rpipes, 1)
# fail early if the become password is wrong
if self._connection_info.become and sudoable:
if self._connection_info.become_pass:
self.check_incorrect_password(stdout)
elif self.check_password_prompt(stdout):
raise AnsibleError('Missing %s password' % self._connection_info.become_method)
if p.stderr in rfd:
dat = os.read(p.stderr.fileno(), 9000)
stderr += dat
if dat == '':
rpipes.remove(p.stderr)
elif p.stdout in rfd:
dat = os.read(p.stdout.fileno(), 9000)
stdout += dat
if dat == '':
rpipes.remove(p.stdout)
# only break out if no pipes are left to read or
# the pipes are completely read and
# the process is terminated
if (not rpipes or not rfd) and p.poll() is not None:
break
# No pipes are left to read but process is not yet terminated
# Only then it is safe to wait for the process to be finished
# NOTE: Actually p.poll() is always None here if rpipes is empty
elif not rpipes and p.poll() == None:
p.wait()
# The process is terminated. Since no pipes to read from are
# left, there is no need to call select() again.
break
# close stdin after process is terminated and stdout/stderr are read
# completely (see also issue #848)
stdin.close()
return (p.returncode, stdout, stderr)
def not_in_host_file(self, host):
if 'USER' in os.environ:
user_host_file = os.path.expandvars("~${USER}/.ssh/known_hosts")
else:
user_host_file = "~/.ssh/known_hosts"
user_host_file = os.path.expanduser(user_host_file)
host_file_list = []
host_file_list.append(user_host_file)
host_file_list.append("/etc/ssh/ssh_known_hosts")
host_file_list.append("/etc/ssh/ssh_known_hosts2")
hfiles_not_found = 0
for hf in host_file_list:
if not os.path.exists(hf):
hfiles_not_found += 1
continue
try:
host_fh = open(hf)
except IOError as e:
hfiles_not_found += 1
continue
else:
data = host_fh.read()
host_fh.close()
for line in data.split("\n"):
if line is None or " " not in line:
continue
tokens = line.split()
if not tokens:
continue
if tokens[0].find(self.HASHED_KEY_MAGIC) == 0:
# this is a hashed known host entry
try:
(kn_salt,kn_host) = tokens[0][len(self.HASHED_KEY_MAGIC):].split("|",2)
hash = hmac.new(kn_salt.decode('base64'), digestmod=sha1)
hash.update(host)
if hash.digest() == kn_host.decode('base64'):
return False
except:
# invalid hashed host key, skip it
continue
else:
# standard host file entry
if host in tokens[0]:
return False
if (hfiles_not_found == len(host_file_list)):
self._display.vvv("EXEC previous known host file not found for {0}".format(host))
return True
def lock_host_keys(self, lock):
if C.HOST_KEY_CHECKING and self.not_in_host_file(self.host):
if lock:
action = fcntl.LOCK_EX
else:
action = fcntl.LOCK_UN
# lock around the initial SSH connectivity so the user prompt about whether to add
# the host to known hosts is not intermingled with multiprocess output.
# FIXME: move the locations of these lock files, same as init above, these came from runner, probably need to be in task_executor
# fcntl.lockf(self.process_lockfile, action)
# fcntl.lockf(self.output_lockfile, action)
def exec_command(self, *args, **kwargs):
"""
Wrapper around _exec_command to retry in the case of an ssh failure
Will retry if:
* an exception is caught
* ssh returns 255
Will not retry if
* remaining_tries is <2
* retries limit reached
"""
remaining_tries = int(C.ANSIBLE_SSH_RETRIES) + 1
cmd_summary = "%s..." % args[0]
for attempt in xrange(remaining_tries):
try:
return_tuple = self._exec_command(*args, **kwargs)
# 0 = success
# 1-254 = remote command return code
# 255 = failure from the ssh command itself
if return_tuple[0] != 255 or attempt == (remaining_tries - 1):
break
else:
raise AnsibleConnectionFailure("Failed to connect to the host via ssh.")
except (AnsibleConnectionFailure, Exception) as e:
if attempt == remaining_tries - 1:
raise e
else:
pause = 2 ** attempt - 1
if pause > 30:
pause = 30
if isinstance(e, AnsibleConnectionFailure):
msg = "ssh_retry: attempt: %d, ssh return code is 255. cmd (%s), pausing for %d seconds" % (attempt, cmd_summary, pause)
else:
msg = "ssh_retry: attempt: %d, caught exception(%s) from cmd (%s), pausing for %d seconds" % (attempt, e, cmd_summary, pause)
self._display.vv(msg)
time.sleep(pause)
continue
return return_tuple
def _exec_command(self, cmd, tmp_path, in_data=None, sudoable=True):
''' run a command on the remote host '''
super(Connection, self).exec_command(cmd, tmp_path, in_data=in_data, sudoable=sudoable)
ssh_cmd = self._password_cmd()
ssh_cmd += ("ssh", "-C")
if not in_data:
# we can only use tty when we are not pipelining the modules. piping data into /usr/bin/python
# inside a tty automatically invokes the python interactive-mode but the modules are not
# compatible with the interactive-mode ("unexpected indent" mainly because of empty lines)
ssh_cmd.append("-tt")
if self._connection_info.verbosity > 3:
ssh_cmd.append("-vvv")
else:
ssh_cmd.append("-q")
ssh_cmd += self._common_args
if self._ipv6:
ssh_cmd += ['-6']
ssh_cmd.append(self.host)
ssh_cmd.append(cmd)
self._display.vvv("EXEC {0}".format(' '.join(ssh_cmd)), host=self.host)
self.lock_host_keys(True)
# create process
(p, stdin) = self._run(ssh_cmd, in_data)
self._send_password()
no_prompt_out = ''
no_prompt_err = ''
if self._connection_info.prompt:
'''
Several cases are handled for privileges with password
* NOPASSWD (tty & no-tty): detect success_key on stdout
* without NOPASSWD:
* detect prompt on stdout (tty)
* detect prompt on stderr (no-tty)
'''
debug("Handling privilege escalation password prompt.")
if self._connection_info.become and self._connection_info.become_pass:
fcntl.fcntl(p.stdout, fcntl.F_SETFL, fcntl.fcntl(p.stdout, fcntl.F_GETFL) | os.O_NONBLOCK)
fcntl.fcntl(p.stderr, fcntl.F_SETFL, fcntl.fcntl(p.stderr, fcntl.F_GETFL) | os.O_NONBLOCK)
become_output = ''
become_errput = ''
while True:
debug('Waiting for Privilege Escalation input')
if self.check_become_success(become_output) or self.check_password_prompt(become_output):
break
rfd, wfd, efd = select.select([p.stdout, p.stderr], [], [p.stdout], self._connection_info.timeout)
if not rfd:
# timeout. wrap up process communication
stdout, stderr = p.communicate()
raise AnsibleError('Connection error waiting for privilege escalation password prompt: %s' % become_output)
elif p.stderr in rfd:
chunk = p.stderr.read()
become_errput += chunk
self.check_incorrect_password(become_errput)
elif p.stdout in rfd:
chunk = p.stdout.read()
become_output += chunk
if not chunk:
raise AnsibleError('Connection closed waiting for privilege escalation password prompt: %s ' % become_output)
if not self.check_become_success(become_output):
debug("Sending privilege escalation password.")
stdin.write(self._connection_info.become_pass + '\n')
else:
no_prompt_out = become_output
no_prompt_err = become_errput
(returncode, stdout, stderr) = self._communicate(p, stdin, in_data, sudoable=sudoable)
self.lock_host_keys(False)
controlpersisterror = 'Bad configuration option: ControlPersist' in stderr or 'unknown configuration option: ControlPersist' in stderr
if C.HOST_KEY_CHECKING:
if ssh_cmd[0] == "sshpass" and p.returncode == 6:
raise AnsibleError('Using a SSH password instead of a key is not possible because Host Key checking is enabled and sshpass does not support this. Please add this host\'s fingerprint to your known_hosts file to manage this host.')
if p.returncode != 0 and controlpersisterror:
raise AnsibleError('using -c ssh on certain older ssh versions may not support ControlPersist, set ANSIBLE_SSH_ARGS="" (or ssh_args in [ssh_connection] section of the config file) before running again')
# FIXME: module name isn't in runner
#if p.returncode == 255 and (in_data or self.runner.module_name == 'raw'):
if p.returncode == 255 and in_data:
raise AnsibleConnectionFailure('SSH Error: data could not be sent to the remote host. Make sure this host can be reached over ssh')
return (p.returncode, '', no_prompt_out + stdout, no_prompt_err + stderr)
def put_file(self, in_path, out_path):
''' transfer a file from local to remote '''
super(Connection, self).put_file(in_path, out_path)
self._display.vvv("PUT {0} TO {1}".format(in_path, out_path), host=self.host)
if not os.path.exists(in_path):
raise AnsibleFileNotFound("file or module does not exist: {0}".format(in_path))
cmd = self._password_cmd()
if C.DEFAULT_SCP_IF_SSH:
cmd.append('scp')
cmd.extend(self._common_args)
cmd.extend([in_path, '{0}:{1}'.format(self.host, pipes.quote(out_path))])
indata = None
else:
cmd.append('sftp')
cmd.extend(self._common_args)
cmd.append(self.host)
indata = "put {0} {1}\n".format(pipes.quote(in_path), pipes.quote(out_path))
(p, stdin) = self._run(cmd, indata)
self._send_password()
(returncode, stdout, stderr) = self._communicate(p, stdin, indata)
if returncode != 0:
raise AnsibleError("failed to transfer file to {0}:\n{1}\n{2}".format(out_path, stdout, stderr))
def fetch_file(self, in_path, out_path):
''' fetch a file from remote to local '''
super(Connection, self).fetch_file(in_path, out_path)
self._display.vvv("FETCH {0} TO {1}".format(in_path, out_path), host=self.host)
cmd = self._password_cmd()
if C.DEFAULT_SCP_IF_SSH:
cmd.append('scp')
cmd.extend(self._common_args)
cmd.extend(['{0}:{1}'.format(self.host, in_path), out_path])
indata = None
else:
cmd.append('sftp')
cmd.extend(self._common_args)
cmd.append(self.host)
indata = "get {0} {1}\n".format(in_path, out_path)
p = subprocess.Popen(cmd, stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
self._send_password()
stdout, stderr = p.communicate(indata)
if p.returncode != 0:
raise AnsibleError("failed to transfer file from {0}:\n{1}\n{2}".format(in_path, stdout, stderr))
def close(self):
''' not applicable since we're executing openssh binaries '''
if self._connected:
if 'ControlMaster' in self._common_args:
cmd = ['ssh','-O','stop']
cmd.extend(self._common_args)
cmd.append(self._connection_info.remote_addr)
p = subprocess.Popen(cmd, stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
stdout, stderr = p.communicate()
self._connected = False