ansible/library/system/authorized_key
kustodian a7839208c7 Updated authorized_key module documentation regarding manage_dir
Added a warning in the documentation about manage_dir when selecting an alternate directory for authorized_keys
2014-01-29 23:39:43 +01:00

423 lines
14 KiB
Python

#!/usr/bin/python
# -*- coding: utf-8 -*-
"""
Ansible module to add authorized_keys for ssh logins.
(c) 2012, Brad Olson <brado@movedbylight.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/>.
"""
DOCUMENTATION = '''
---
module: authorized_key
short_description: Adds or removes an SSH authorized key
description:
- Adds or removes an SSH authorized key for a user from a remote host.
version_added: "0.5"
options:
user:
description:
- The username on the remote host whose authorized_keys file will be modified
required: true
default: null
aliases: []
key:
description:
- The SSH public key, as a string
required: true
default: null
path:
description:
- Alternate path to the authorized_keys file
required: false
default: "(homedir)+/.ssh/authorized_keys"
version_added: "1.2"
manage_dir:
description:
- Whether this module should manage the directory of the authorized_keys file. Make sure to set C(manage_dir=no) if you are using an alternate directory for authorized_keys set with C(path), since you could lock yourself out of SSH access. See the example below.
required: false
choices: [ "yes", "no" ]
default: "yes"
version_added: "1.2"
state:
description:
- Whether the given key (with the given key_options) should or should not be in the file
required: false
choices: [ "present", "absent" ]
default: "present"
key_options:
description:
- A string of ssh key options to be prepended to the key in the authorized_keys file
required: false
default: null
version_added: "1.4"
description:
- "Adds or removes authorized keys for particular user accounts"
author: Brad Olson
'''
EXAMPLES = '''
# Example using key data from a local file on the management machine
- authorized_key: user=charlie key="{{ lookup('file', '/home/charlie/.ssh/id_rsa.pub') }}"
# Using alternate directory locations:
- authorized_key: user=charlie
key="{{ lookup('file', '/home/charlie/.ssh/id_rsa.pub') }}"
path='/etc/ssh/authorized_keys/charlie'
manage_dir=no
# Using with_file
- name: Set up authorized_keys for the deploy user
authorized_key: user=deploy
key="{{ item }}"
with_file:
- public_keys/doe-jane
- public_keys/doe-john
# Using key_options:
- authorized_key: user=charlie
key="{{ lookup('file', '/home/charlie/.ssh/id_rsa.pub') }}"
key_options='no-port-forwarding,host="10.0.1.1"'
'''
# Makes sure the public key line is present or absent in the user's .ssh/authorized_keys.
#
# Arguments
# =========
# user = username
# key = line to add to authorized_keys for user
# path = path to the user's authorized_keys file (default: ~/.ssh/authorized_keys)
# manage_dir = whether to create, and control ownership of the directory (default: true)
# state = absent|present (default: present)
#
# see example in examples/playbooks
import sys
import os
import pwd
import os.path
import tempfile
import re
import shlex
class keydict(dict):
""" a dictionary that maintains the order of keys as they are added """
# http://stackoverflow.com/questions/2328235/pythonextend-the-dict-class
def __init__(self, *args, **kw):
super(keydict,self).__init__(*args, **kw)
self.itemlist = super(keydict,self).keys()
def __setitem__(self, key, value):
self.itemlist.append(key)
super(keydict,self).__setitem__(key, value)
def __iter__(self):
return iter(self.itemlist)
def keys(self):
return self.itemlist
def values(self):
return [self[key] for key in self]
def itervalues(self):
return (self[key] for key in self)
def keyfile(module, user, write=False, path=None, manage_dir=True):
"""
Calculate name of authorized keys file, optionally creating the
directories and file, properly setting permissions.
:param str user: name of user in passwd file
:param bool write: if True, write changes to authorized_keys file (creating directories if needed)
:param str path: if not None, use provided path rather than default of '~user/.ssh/authorized_keys'
:param bool manage_dir: if True, create and set ownership of the parent dir of the authorized_keys file
:return: full path string to authorized_keys for user
"""
try:
user_entry = pwd.getpwnam(user)
except KeyError, e:
module.fail_json(msg="Failed to lookup user %s: %s" % (user, str(e)))
if path is None:
homedir = user_entry.pw_dir
sshdir = os.path.join(homedir, ".ssh")
keysfile = os.path.join(sshdir, "authorized_keys")
else:
sshdir = os.path.dirname(path)
keysfile = path
if not write:
return keysfile
uid = user_entry.pw_uid
gid = user_entry.pw_gid
if manage_dir in BOOLEANS_TRUE:
if not os.path.exists(sshdir):
os.mkdir(sshdir, 0700)
if module.selinux_enabled():
module.set_default_selinux_context(sshdir, False)
os.chown(sshdir, uid, gid)
os.chmod(sshdir, 0700)
if not os.path.exists(keysfile):
basedir = os.path.dirname(keysfile)
if not os.path.exists(basedir):
os.makedirs(basedir)
try:
f = open(keysfile, "w") #touches file so we can set ownership and perms
finally:
f.close()
if module.selinux_enabled():
module.set_default_selinux_context(keysfile, False)
try:
os.chown(keysfile, uid, gid)
os.chmod(keysfile, 0600)
except OSError:
pass
return keysfile
def parseoptions(module, options):
'''
reads a string containing ssh-key options
and returns a dictionary of those options
'''
options_dict = keydict() #ordered dict
if options:
token_exp = [
# matches separator
(r',+', False),
# matches option with value, e.g. from="x,y"
(r'([a-z0-9-]+)="((?:[^"\\]|\\.)*)"', True),
# matches single option, e.g. no-agent-forwarding
(r'[a-z0-9-]+', True)
]
pos = 0
while pos < len(options):
match = None
for pattern, is_valid_option in token_exp:
regex = re.compile(pattern, re.IGNORECASE)
match = regex.match(options, pos)
if match:
text = match.group(0)
if is_valid_option:
if len(match.groups()) == 2:
options_dict[match.group(1)] = match.group(2)
else:
options_dict[text] = None
break
if not match:
module.fail_json(msg="invalid option string: %s" % options)
else:
pos = match.end(0)
return options_dict
def parsekey(module, raw_key):
'''
parses a key, which may or may not contain a list
of ssh-key options at the beginning
'''
VALID_SSH2_KEY_TYPES = [
'ecdsa-sha2-nistp256',
'ecdsa-sha2-nistp384',
'ecdsa-sha2-nistp521',
'ssh-dss',
'ssh-rsa',
]
options = None # connection options
key = None # encrypted key string
key_type = None # type of ssh key
type_index = None # index of keytype in key string|list
# remove comment yaml escapes
raw_key = raw_key.replace('\#', '#')
# split key safely
lex = shlex.shlex(raw_key)
lex.quotes = ["'", '"']
lex.commenters = '' #keep comment hashes
lex.whitespace_split = True
key_parts = list(lex)
for i in range(0, len(key_parts)):
if key_parts[i] in VALID_SSH2_KEY_TYPES:
type_index = i
key_type = key_parts[i]
break
# check for options
if type_index is None:
return None
elif type_index > 0:
options = " ".join(key_parts[:type_index])
# parse the options (if any)
options = parseoptions(module, options)
# get key after the type index
key = key_parts[(type_index + 1)]
# set comment to everything after the key
if len(key_parts) > (type_index + 1):
comment = " ".join(key_parts[(type_index + 2):])
return (key, key_type, options, comment)
def readkeys(module, filename):
if not os.path.isfile(filename):
return {}
keys = {}
f = open(filename)
for line in f.readlines():
key_data = parsekey(module, line)
if key_data:
# use key as identifier
keys[key_data[0]] = key_data
else:
# for an invalid line, just append the line
# to the array so it will be re-output later
keys[line] = line
f.close()
return keys
def writekeys(module, filename, keys):
fd, tmp_path = tempfile.mkstemp('', 'tmp', os.path.dirname(filename))
f = open(tmp_path,"w")
try:
for index, key in keys.items():
try:
(keyhash,type,options,comment) = key
option_str = ""
if options:
option_strings = []
for option_key in options.keys():
if options[option_key]:
option_strings.append("%s=\"%s\"" % (option_key, options[option_key]))
else:
option_strings.append("%s" % option_key)
option_str = ",".join(option_strings)
option_str += " "
key_line = "%s%s %s %s\n" % (option_str, type, keyhash, comment)
except:
key_line = key
f.writelines(key_line)
except IOError, e:
module.fail_json(msg="Failed to write to file %s: %s" % (tmp_path, str(e)))
f.close()
module.atomic_move(tmp_path, filename)
def enforce_state(module, params):
"""
Add or remove key.
"""
user = params["user"]
key = params["key"]
path = params.get("path", None)
manage_dir = params.get("manage_dir", True)
state = params.get("state", "present")
key_options = params.get("key_options", None)
# extract indivial keys into an array, skipping blank lines and comments
key = [s for s in key.splitlines() if s and not s.startswith('#')]
# check current state -- just get the filename, don't create file
do_write = False
params["keyfile"] = keyfile(module, user, do_write, path, manage_dir)
existing_keys = readkeys(module, params["keyfile"])
# Check our new keys, if any of them exist we'll continue.
for new_key in key:
parsed_new_key = parsekey(module, new_key)
if key_options is not None:
parsed_options = parseoptions(module, key_options)
parsed_new_key = (parsed_new_key[0], parsed_new_key[1], parsed_options, parsed_new_key[3])
if not parsed_new_key:
module.fail_json(msg="invalid key specified: %s" % new_key)
present = False
matched = False
non_matching_keys = []
if parsed_new_key[0] in existing_keys:
present = True
# Then we check if everything matches, including
# the key type and options. If not, we append this
# existing key to the non-matching list
# We only want it to match everything when the state
# is present
if parsed_new_key != existing_keys[parsed_new_key[0]] and state == "present":
non_matching_keys.append(existing_keys[parsed_new_key[0]])
else:
matched = True
# handle idempotent state=present
if state=="present":
if len(non_matching_keys) > 0:
for non_matching_key in non_matching_keys:
if non_matching_key[0] in existing_keys:
del existing_keys[non_matching_key[0]]
do_write = True
if not matched:
existing_keys[parsed_new_key[0]] = parsed_new_key
do_write = True
elif state=="absent":
if not matched:
continue
del existing_keys[parsed_new_key[0]]
do_write = True
if do_write:
writekeys(module, keyfile(module, user, do_write, path, manage_dir), existing_keys)
params['changed'] = True
return params
def main():
module = AnsibleModule(
argument_spec = dict(
user = dict(required=True, type='str'),
key = dict(required=True, type='str'),
path = dict(required=False, type='str'),
manage_dir = dict(required=False, type='bool', default=True),
state = dict(default='present', choices=['absent','present']),
key_options = dict(required=False, type='str'),
unique = dict(default=False, type='bool'),
)
)
results = enforce_state(module, module.params)
module.exit_json(**results)
# import module snippets
from ansible.module_utils.basic import *
main()