#!/usr/bin/env python

# (C) Copyright 2015 Hewlett Packard Enterprise Development LP

# All Rights Reserved.

#

# Licensed under the Apache License, Version 2.0 (the "License"); you may

# not use this file except in compliance with the License. You may obtain

# a copy of the License at

#

# http://www.apache.org/licenses/LICENSE-2.0

#

# Unless required by applicable law or agreed to in writing, software

# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT

# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the

# License for the specific language governing permissions and limitations

# under the License..

'''

NOTES:

- DHCP-TFTP python daemon. This is a helper daemon

to retrieve the DHCP-TFTP server configs from OVSDB

during bootup and starts the dnsmasq dameon (open source

daemon for DHCP-TFTP functionality). Then it monitors

OVSDB for any config changes related to DHCP-TFTP server

and if there is any it kills dnsmasq daemon and restarts

with new config.

'''

import argparse

import os

import sys

import subprocess

from time import sleep

import signal

import ovs.dirs

from ovs.db import error

from ovs.db import types

import ovs.daemon

import ovs.db.idl

import ovs.unixctl

import ovs.unixctl.server

from ops_eventlog import event_log_init

from ops_eventlog import log_event

import ops_diagdump

# OVS definitions

idl = None

# Tables definitions

SYSTEM_TABLE = 'System'

VRF_TABLE = 'VRF'

DHCP_SERVER_TABLE = 'DHCP_Server'

DHCP_SERVER_RANGE_TABLE = 'DHCPSrv_Range'

DHCP_SERVER_STATIC_HOST_TABLE = 'DHCPSrv_Static_Host'

DHCP_SERVER_OPTION_TABLE = 'DHCPSrv_Option'

DHCP_SERVER_MATCH_TABLE = 'DHCPSrv_Match'

# Columns definitions - System Table

SYSTEM_VRFS = 'vrfs'

SYSTEM_CUR_CFG = 'cur_cfg'

SYSTEM_OTHER_CONFIG = 'other_config'

# Columns definitions - VRF Table

VRF_NAME = 'name'

VRF_DHCP_SERVER = 'dhcp_server'

VRF_OTHER_CONFIG = 'other_config'

# Columns definitions - DHCPSrv_Range Table

DHCP_RANGE_START_IP = 'start_ip_address'

DHCP_RANGE_END_IP = 'end_ip_address'

DHCP_RANGE_TAG = 'tag'

DHCP_RANGE_MODE = 'mode'

DHCP_RANGE_LEASE_DURATION = 'lease_duration'

# Columns definitions - DHCPSrv_Host Table

DHCP_HOST_MAC_ADDRESS = 'mac_address'

DHCP_HOST_TAG = 'tag'

DHCP_HOST_IP_ADDRESS = 'ip_address'

DHCP_HOST_CLIENT_NAME = 'client_hostname'

DHCP_HOST_CLIENT_ID = 'client_id'

# Columns definitions - DHCPSrv_Option Table

DHCP_OPTION_TAG = 'tag'

DHCP_OPTION_NAME = 'option_name'

DHCP_OPTION_NUMBER = 'option_number'

DHCP_OPTION_VALUE = 'option_value'

DHCP_OPTION_IPV6 = 'ipv6'

# Columns definitions - DHCPSrv_Boot Table

DHCP_BOOT_TAG = 'tag'

DHCP_BOOT_FILE_NAME = 'file_name'

# Default DB path

def_db = 'unix:/var/run/openvswitch/db.sock'

# OPS_TODO: Need to pull these from the build env

ovs_schema = '/usr/share/openvswitch/vswitch.ovsschema'

vlog = ovs.vlog.Vlog("dhcp_tftp")

exiting = False

seqno = 0

dnsmasq_process = None

dnsmasq_started = False

dnsmasq_command = None

dhcp_range_config = False

# OPS_TODO: Remove the log facility option before final release

dnsmasq_default_command = ('/usr/bin/dnsmasq --port=0 --user=root '

'--dhcp-script=/usr/bin/dhcp_leases --leasefile-ro '

'--log-facility=/tmp/dnsmasq.log ')

dnsmasq_dhcp_range_option = '--dhcp-range='

dnsmasq_dhcp_host_option = '--dhcp-host='

dnsmasq_dhcp_option_arg = '--dhcp-option='

dnsmasq_dhcp_boot_option = '--dhcp-boot='

def unixctl_exit(conn, unused_argv, unused_aux):

global exiting

exiting = True

conn.reply(None)

# ------------------ db_get_system_status() ----------------

def db_get_system_status(data):

return False

# ------------------ system_is_configured() ----------------

def system_is_configured():

return True

# ------------------ terminate() ----------------

def terminate():

global exiting

# Exiting daemon

exiting = True

# ------- ops_dhcp_tftp_diagnostics_handler() -------

def ops_dhcp_tftp_diagnostics_handler(argv):

return buff

# ------------------ dhcp_tftp_init() ----------------

def dhcp_tftp_init(remote):

idl = ovs.db.idl.Idl(remote, schema_helper)

# ------------------ dhcp_tftp_get_config() ---------

def dhcp_tftp_get_config():

% (dnsmasq_command))

# ------------------ dnsmasq_start_process() ----------

def dnsmasq_start_process():

["dnsmasq_command", dnsmasq_command])

# ------------------ dnsmasq_run() ----------------

def dnsmasq_run():

dnsmasq_started = True

# --------------------- dnsmasq_restart() --------------

def dnsmasq_restart():

dnsmasq_start_process()

# ------------------ main() ----------------

def main():

idl.close()

if __name__ == '__main__':

try:

main()

except SystemExit:

# Let system.exit() calls complete normally

raise

except:

vlog.exception("traceback")

sys.exit(ovs.daemon.RESTART_EXIT_CODE)