#!/usr/bin/python # -*- coding: utf-8 -*- # (c) 2012, David "DaviXX" CHANIAL # (c) 2014, James Tanner # # 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 . # DOCUMENTATION = ''' --- module: sysctl short_description: Manage entries in sysctl.conf. description: - This module manipulates sysctl entries and optionally performs a C(/sbin/sysctl -p) after changing them. version_added: "1.0" options: name: description: - The dot-separated path (aka I(key)) specifying the sysctl variable. required: true default: null aliases: [ 'key' ] value: description: - Desired value of the sysctl key. required: false default: null aliases: [ 'val' ] state: description: - Whether the entry should be present or absent in the sysctl file. choices: [ "present", "absent" ] default: present reload: description: - If C(yes), performs a I(/sbin/sysctl -p) if the C(sysctl_file) is updated. If C(no), does not reload I(sysctl) even if the C(sysctl_file) is updated. choices: [ "yes", "no" ] default: "yes" sysctl_file: description: - Specifies the absolute path to C(sysctl.conf), if not C(/etc/sysctl.conf). required: false default: /etc/sysctl.conf sysctl_set: description: - Verify token value with the sysctl command and set with -w if necessary choices: [ "yes", "no" ] required: false version_added: 1.5 default: False notes: [] requirements: [] author: David "DaviXX" CHANIAL ''' EXAMPLES = ''' # Set vm.swappiness to 5 in /etc/sysctl.conf - sysctl: name=vm.swappiness value=5 state=present # Remove kernel.panic entry from /etc/sysctl.conf - sysctl: name=kernel.panic state=absent sysctl_file=/etc/sysctl.conf # Set kernel.panic to 3 in /tmp/test_sysctl.conf - sysctl: name=kernel.panic value=3 sysctl_file=/tmp/test_sysctl.conf reload=no # Set ip fowarding on in /proc and do not reload the sysctl file - sysctl: name="net.ipv4.ip_forward" value=1 sysctl_set=yes # Set ip forwarding on in /proc and in the sysctl file and reload if necessary - sysctl: name="net.ipv4.ip_forward" value=1 sysctl_set=yes state=present reload=yes ''' # ============================================================== import os import tempfile import re class SysctlModule(object): def __init__(self, module): self.module = module self.args = self.module.params self.sysctl_cmd = self.module.get_bin_path('sysctl', required=True) self.sysctl_file = self.args['sysctl_file'] self.proc_value = None # current token value in proc fs self.file_value = None # current token value in file self.file_lines = [] # all lines in the file self.file_values = {} # dict of token values self.changed = False # will change occur self.set_proc = False # does sysctl need to set value self.write_file = False # does the sysctl file need to be reloaded self.process() # ============================================================== # LOGIC # ============================================================== def process(self): # Whitespace is bad self.args['name'] = self.args['name'].strip() if self.args['value'] is not None: self.args['value'] = self.args['value'].strip() else: self.args['value'] = "" thisname = self.args['name'] # get the current proc fs value self.proc_value = self.get_token_curr_value(thisname) # get the currect sysctl file value self.read_sysctl_file() if thisname not in self.file_values: self.file_values[thisname] = None # update file contents with desired token/value self.fix_lines() # what do we need to do now? if self.file_values[thisname] is None and self.args['state'] == "present": self.changed = True self.write_file = True elif self.file_values[thisname] != self.args['value']: self.changed = True self.write_file = True if self.args['sysctl_set']: if self.proc_value is None: self.changed = True elif not self._values_is_equal(self.proc_value, self.args['value']): self.changed = True self.set_proc = True # Do the work if not self.module.check_mode: if self.write_file: self.write_sysctl() if self.write_file and self.args['reload']: self.reload_sysctl() if self.set_proc: self.set_token_value(self.args['name'], self.args['value']) def _values_is_equal(self, a, b): """Expects two string values. It will split the string by whitespace and compare each value. It will return True if both lists are the same, contain the same elements and the same order.""" if a is None or b is None: return False a = a.split() b = b.split() if len(a) != len(b): return False return len([i for i, j in zip(a, b) if i == j]) == len(a) # ============================================================== # SYSCTL COMMAND MANAGEMENT # ============================================================== # Use the sysctl command to find the current value def get_token_curr_value(self, token): thiscmd = "%s -e -n %s" % (self.sysctl_cmd, token) rc,out,err = self.module.run_command(thiscmd) if rc != 0: return None else: return out # Use the sysctl command to set the current value def set_token_value(self, token, value): if len(value.split()) > 0: value = '"' + value + '"' thiscmd = "%s -w %s=%s" % (self.sysctl_cmd, token, value) rc,out,err = self.module.run_command(thiscmd) if rc != 0: self.module.fail_json(msg='setting %s failed: %s' % (token, out + err)) else: return rc # Run sysctl -p def reload_sysctl(self): # do it if get_platform().lower() == 'freebsd': # freebsd doesn't support -p, so reload the sysctl service rc,out,err = self.module.run_command('/etc/rc.d/sysctl reload') else: # system supports reloading via the -p flag to sysctl, so we'll use that rc,out,err = self.module.run_command([self.sysctl_cmd, '-p', self.sysctl_file]) if rc != 0: self.module.fail_json(msg="Failed to reload sysctl: %s" % str(out) + str(err)) # ============================================================== # SYSCTL FILE MANAGEMENT # ============================================================== # Get the token value from the sysctl file def read_sysctl_file(self): lines = open(self.sysctl_file, "r").readlines() for line in lines: line = line.strip() self.file_lines.append(line) # don't split empty lines or comments if not line or line.startswith("#"): continue k, v = line.split('=',1) k = k.strip() v = v.strip() self.file_values[k] = v.strip() # Fix the value in the sysctl file content def fix_lines(self): checked = [] self.fixed_lines = [] for line in self.file_lines: if not line.strip() or line.strip().startswith("#"): self.fixed_lines.append(line) continue tmpline = line.strip() k, v = line.split('=',1) k = k.strip() v = v.strip() if k not in checked: checked.append(k) if k == self.args['name']: if self.args['state'] == "present": new_line = "%s = %s\n" % (k, self.args['value']) self.fixed_lines.append(new_line) else: new_line = "%s = %s\n" % (k, v) self.fixed_lines.append(new_line) if self.args['name'] not in checked and self.args['state'] == "present": new_line = "%s = %s\n" % (self.args['name'], self.args['value']) self.fixed_lines.append(new_line) # Completely rewrite the sysctl file def write_sysctl(self): # open a tmp file fd, tmp_path = tempfile.mkstemp('.conf', '.ansible_m_sysctl_', os.path.dirname(self.sysctl_file)) f = open(tmp_path,"w") try: for l in self.fixed_lines: f.write(l.strip() + "\n") except IOError, e: self.module.fail_json(msg="Failed to write to file %s: %s" % (tmp_path, str(e))) f.flush() f.close() # replace the real one self.module.atomic_move(tmp_path, self.sysctl_file) # ============================================================== # main def main(): # defining module module = AnsibleModule( argument_spec = dict( name = dict(aliases=['key'], required=True), value = dict(aliases=['val'], required=False), state = dict(default='present', choices=['present', 'absent']), reload = dict(default=True, type='bool'), sysctl_set = dict(default=False, type='bool'), sysctl_file = dict(default='/etc/sysctl.conf') ), supports_check_mode=True ) result = SysctlModule(module) module.exit_json(changed=result.changed) sys.exit(0) # import module snippets from ansible.module_utils.basic import * main()