ansible/library/system/capabilities

187 lines
6.8 KiB
Python

#!/usr/bin/python
# -*- coding: utf-8 -*-
# (c) 2014, Nate Coraor <nate@bx.psu.edu>
#
# 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: capabilities
short_description: Manage Linux capabilities
description:
- This module manipulates files' priviliges using the Linux capabilities(7) system.
version_added: "1.0"
options:
path:
description:
- Specifies the path to the file to be managed.
required: true
default: null
capability:
description:
- Desired capability to set (with operator and flags, if state is C(present)) or remove (if state is C(absent))
required: true
default: null
aliases: [ 'cap' ]
state:
description:
- Whether the entry should be present or absent in the file's capabilities.
choices: [ "present", "absent" ]
default: present
notes:
- The capabilities system will automatically transform operators and flags
into the effective set, so (for example, cap_foo=ep will probably become
cap_foo+ep). This module does not attempt to determine the final operator
and flags to compare, so you will want to ensure that your capabilities
argument matches the final capabilities.
requirements: []
author: Nate Coraor <nate@bx.psu.edu>
'''
EXAMPLES = '''
# Set cap_sys_chroot+ep on /foo
- capabilities: path=/foo capability=cap_sys_chroot+ep state=present
# Remove cap_net_bind_service from /bar
- capabilities: path=/bar capability=cap_net_bind_service state=absent
'''
OPS = ( '=', '-', '+' )
# ==============================================================
import os
import tempfile
import re
class CapabilitiesModule(object):
platform = 'Linux'
distribution = None
def __init__(self, module):
self.module = module
self.path = module.params['path'].strip()
self.capability = module.params['capability'].strip().lower()
self.state = module.params['state']
self.getcap_cmd = module.get_bin_path('getcap', required=True)
self.setcap_cmd = module.get_bin_path('setcap', required=True)
self.capability_tup = self._parse_cap(self.capability, op_required=self.state=='present')
self.run()
def run(self):
current = self.getcap(self.path)
caps = [ cap[0] for cap in current ]
if self.state == 'present' and self.capability_tup not in current:
# need to add capability
if self.module.check_mode:
self.module.exit_json(changed=True, msg='capabilities changed')
else:
# remove from current cap list if it's already set (but op/flags differ)
current = filter(lambda x: x[0] != self.capability_tup[0], current)
# add new cap with correct op/flags
current.append( self.capability_tup )
self.module.exit_json(changed=True, state=self.state, msg='capabilities changed', stdout=self.setcap(self.path, current))
elif self.state == 'absent' and self.capability_tup[0] in caps:
# need to remove capability
if self.module.check_mode:
self.module.exit_json(changed=True, msg='capabilities changed')
else:
# remove from current cap list and then set current list
current = filter(lambda x: x[0] != self.capability_tup[0], current)
self.module.exit_json(changed=True, state=self.state, msg='capabilities changed', stdout=self.setcap(self.path, current))
self.module.exit_json(changed=False, state=self.state)
def getcap(self, path):
rval = []
cmd = "%s -v %s" % (self.getcap_cmd, path)
rc, stdout, stderr = self.module.run_command(cmd)
# If file xattrs are set but no caps are set the output will be:
# '/foo ='
# If file xattrs are unset the output will be:
# '/foo'
# If the file does not eixst the output will be (with rc == 0...):
# '/foo (No such file or directory)'
if rc != 0 or (stdout.strip() != path and stdout.count(' =') != 1):
self.module.fail_json(msg="Unable to get capabilities of %s" % path, stdout=stdout.strip(), stderr=stderr)
if stdout.strip() != path:
caps = stdout.split(' =')[1].strip().split()
for cap in caps:
cap = cap.lower()
# getcap condenses capabilities with the same op/flags into a
# comma-separated list, so we have to parse that
if ',' in cap:
cap_group = cap.split(',')
cap_group[-1], op, flags = self._parse_cap(cap_group[-1])
for subcap in cap_group:
rval.append( ( subcap, op, flags ) )
else:
rval.append(self._parse_cap(cap))
return rval
def setcap(self, path, caps):
caps = ' '.join([ ''.join(cap) for cap in caps ])
cmd = "%s '%s' %s" % (self.setcap_cmd, caps, path)
rc, stdout, stderr = self.module.run_command(cmd)
if rc != 0:
self.module.fail_json(msg="Unable to set capabilities of %s" % path, stdout=stdout, stderr=stderr)
else:
return stdout
def _parse_cap(self, cap, op_required=True):
opind = -1
try:
i = 0
while opind == -1:
opind = cap.find(OPS[i])
i += 1
except:
if op_required:
self.module.fail_json(msg="Couldn't find operator (one of: %s)" % str(OPS))
else:
return (cap, None, None)
op = cap[opind]
cap, flags = cap.split(op)
return (cap, op, flags)
# ==============================================================
# main
def main():
# defining module
module = AnsibleModule(
argument_spec = dict(
path = dict(aliases=['key'], required=True),
capability = dict(aliases=['cap'], required=True),
state = dict(default='present', choices=['present', 'absent']),
),
supports_check_mode=True
)
CapabilitiesModule(module)
sys.exit(0)
# import module snippets
from ansible.module_utils.basic import *
main()