core/usr/local/opnsense/service/modules/processhandler.py
2014-12-08 15:36:19 +01:00

333 lines
13 KiB
Python

"""
Copyright (c) 2014 Ad Schellevis
part of opnSense (https://www.opnsense.org/)
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
1. Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.
--------------------------------------------------------------------------------------
package : check_reload_status
function: unix domain socket process worker process
"""
__author__ = 'Ad Schellevis'
import os
import subprocess
import socket
import traceback
import syslog
import threading
import ConfigParser
import glob
import time
class Handler(object):
""" Main handler class, opens unix domain socket and starts listening
- New connections are handed over to a HandlerClient type object in a new thread
- All possible actions are stored in 1 ActionHandler type object and parsed to every client for script execution
processflow:
Handler ( waits for client )
-> new client is send to HandlerClient
-> execute ActionHandler command
<- send back result string
"""
def __init__(self,socket_filename,config_path,simulation_mode=False):
""" Constructor
:param socket_filename: filename of unix domain socket to use
:param config_path: location of configuration files
:param emulate: emulation mode, do not start actual (script) commands
:return: object
"""
self.socket_filename = socket_filename
self.config_path = config_path
self.simulation_mode =simulation_mode
def run(self):
""" Run process handler
:return:
"""
while True:
try:
# open action handler
actHandler = ActionHandler(config_path=self.config_path)
# remove previous socket ( if exists )
try:
os.unlink(self.socket_filename)
except OSError:
if os.path.exists(self.socket_filename):
raise
sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
sock.bind(self.socket_filename)
os.chmod(self.socket_filename,0o666)
sock.listen(30)
while True:
# wait for a connection to arrive
connection, client_address = sock.accept()
# spawn a client connection
cmd_thread = HandlerClient(connection=connection,
client_address=client_address,
action_handler=actHandler,
simulation_mode=self.simulation_mode)
cmd_thread.start()
except KeyboardInterrupt:
# exit on <ctrl><c>
raise
except:
# something went wrong... send traceback to syslog, restart listener (wait for a short time)
print (traceback.format_exc())
syslog.syslog(syslog.LOG_ERR, 'Handler died on %s'%traceback.format_exc())
time.sleep(1)
class HandlerClient(threading.Thread):
""" Handle commands via specified socket connection
"""
def __init__ (self,connection,client_address,action_handler,simulation_mode=False):
"""
:param connection: socket connection object
:param client_address: client address ( from socket accept )
:param action_handler: action handler object
:param emulate: Emulation mode, do not start actual (script) commands
:return: None
"""
threading.Thread.__init__(self)
self.connection = connection
self.client_address = client_address
self.action_handler = action_handler
self.simulation_mode = simulation_mode
def run(self):
""" handle single action ( read data, execute command, send response )
:return: None
"""
try:
# receive command, maximum data length is 4k... longer messages will be truncated
data = self.connection.recv(4096)
# map command to action
data_parts = data.strip().split(' ')
if len(data_parts) == 0 or len(data_parts[0]) == 0:
# no data found
self.connection.sendall('no data\n')
else:
exec_command = data_parts[0]
if len(data_parts) > 1:
exec_action = data_parts[1]
else:
exec_action = None
if len(data_parts) >2:
exec_params = data_parts[2:]
else:
exec_params = None
# execute requested action
if self.simulation_mode:
self.action_handler.showAction(exec_command,exec_action,exec_params)
result='OK'
else:
result = self.action_handler.execute(exec_command,exec_action,exec_params)
# send response back to client( including trailing enter )
self.connection.sendall('%s\n'%result)
except:
print (traceback.format_exc())
syslog.syslog(syslog.LOG_ERR,'unable to sendback response, message was %s'%traceback.format_exc())
finally:
self.connection.close()
class Action(object):
""" Action class, handles actual system calls. set command, parameters (template) type and log message
"""
def __init__(self):
""" setup default properties
:return:
"""
self.command = None
self.parameters = None
self.type = None
self.message = None
self._parameter_start_pos = 0
def setParameterStartPos(self,pos):
"""
:param pos: start position of parameter list
:return: position
"""
self._parameter_start_pos = pos
def getParameterStartPos(self):
""" getter for _parameter_start_pos
:return: start position of parameter list ( first argument can be part of action to start )
"""
return self._parameter_start_pos
def execute(self,parameters):
""" execute an action
:param parameters: list of parameters
:return:
"""
# validate input
if self.type == None:
return 'No action type'
elif self.type.lower() == 'script':
if self.command == None:
return 'No command'
try:
script_command = self.command
if self.parameters != None and type(self.parameters) == str:
script_command = '%s %s'%(script_command,self.parameters)
if script_command.find('%s') > -1 and len(parameters) > 0:
# use command execution parameters in action parameter template
script_command = script_command % tuple(parameters[0:script_command.count('%s')])
# execute script command
if self.message != None:
if self.message.count('%s') > 0 and parameters != None and len(parameters) > 0:
syslog.syslog(syslog.LOG_NOTICE,self.message % tuple(parameters[0:self.message.count('%s')]) )
else:
syslog.syslog(syslog.LOG_NOTICE,self.message)
exit_status = subprocess.call(script_command, shell=True)
except:
print traceback.format_exc()
# todo log traceback on exception
return 'Execute error'
# send response
if exit_status == 0 :
return 'OK'
else:
return 'Error (%d)'%exit_status
return 'Unknown action type'
class ActionHandler(object):
""" Start/stop services and functions using configuration data definced in conf/actions_<topic>.conf
"""
def __init__(self,config_path):
""" Initialize action handler to start system functions
:param config_path: full path of configuration data
:return:
"""
self.config_path = config_path
self.action_map = {}
self.load_config()
def load_config(self):
""" load action configuration from config files into local dictionary
:return: None
"""
self.action_map = {}
for config_filename in glob.glob('%s/actions_*.conf'%(self.config_path)):
# traverse config directory and open all filenames starting with actions_
cnf=ConfigParser.RawConfigParser()
cnf.read(config_filename)
topic_map = {}
for section in cnf.sections():
# map configuration data on object
action_obj = Action()
for act_prop in cnf.items(section):
setattr(action_obj,act_prop[0],act_prop[1])
if section.find('.') > -1:
# at this moment we only support 2 levels of actions ( 3 if you count topic as well )
for alias in section.split('.')[0].split('|'):
if topic_map.has_key(alias) == False:
topic_map[alias] = {}
topic_map[alias][section.split('.')[1]] = action_obj
else:
for alias in section.split('|'):
topic_map[alias] = action_obj
self.action_map[config_filename.split('actions_')[-1].split('.')[0]] = topic_map
def findAction(self,command,action,parameters):
""" find action object
:param command: command/topic for example interface
:param action: action to run ( for example linkup )
:param parameters: the parameters to supply
:return: action object or None if not found
"""
action_obj = None
if self.action_map.has_key(command):
if self.action_map[command].has_key(action):
if type(self.action_map[command][action]) == dict:
if len(parameters) > 0 and self.action_map[command][action].has_key(parameters[0]) == True:
# 3 level action ( "interface linkup start" for example )
if isinstance(self.action_map[command][action][parameters[0]],Action):
action_obj = self.action_map[command][action][parameters[0]]
action_obj.setParameterStartPos(1)
elif isinstance(self.action_map[command][action],Action):
action_obj = self.action_map[command][action]
return action_obj
def execute(self,command,action,parameters):
""" execute configuration defined action
:param command: command/topic for example interface
:param action: action to run ( for example linkup )
:param parameters: the parameters to supply
:return: OK on success, else error code
"""
action_params = []
action_obj = self.findAction(command,action,parameters)
if action_obj != None:
if parameters != None and len(parameters) > action_obj.getParameterStartPos():
action_params = parameters[action_obj.getParameterStartPos():]
return '%s\n'%action_obj.execute(action_params)
return 'Action not found\n'
def showAction(self,command,action,parameters):
""" debug/simulation mode: show action information
:return:
"""
action_obj = self.findAction(command,action,parameters)
print ('---------------------------------------------------------------------')
print ('execute %s.%s with parameters : %s '%(command,action,parameters) )
print ('action object %s (%s)' % (action_obj,action_obj.command) )
print ('---------------------------------------------------------------------')