ShaYmez/DMRlink
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity
2e0f29fc97
DMRlink/ipsc.py
Cort Buffington 2e0f29fc97 Peer Validation - In Progress 
Mostly done.. must find a way to allow master registration and
reception of peer list BEFORE validating incoming messages to the peer
list -- chicken and egg problem. Easily solved, but needs an EFFICIENT
solution since EVERY PACKET will be passed through this test.
2013-07-30 10:52:10 -05:00

436 lines
18 KiB
Python
Raw Blame History

from __future__ import print_function
from twisted.internet.protocol import DatagramProtocol
from twisted.internet import reactor
from twisted.internet import task
import sys
import argparse
import binascii
import hmac
import hashlib
import socket
#from logging.config import dictConfig
#import logging
#************************************************
# IMPORTING OTHER FILES - '#include'
#************************************************
# Import system logger configuration
#
try:
from ipsc_logger import logger
except ImportError:
sys.exit('System logger configuraiton not found or invalid')
# Import configuration and informational data structures
#
try:
from my_ipsc_config import NETWORK
except ImportError:
sys.exit('Configuration file not found, or not valid formatting')
# Import IPSC message types and version information
#
try:
from ipsc_message_types import *
except ImportError:
sys.exit('IPSC message types file not found or invalid')
# Import IPSC flag mask values
#
try:
from ipsc_mask import *
except ImportError:
sys.exit('IPSC mask values file not found or invalid')
#************************************************
# GLOBALLY SCOPED FUNCTIONS
#************************************************
# Remove the hash from a paket and return the payload
#
def strip_hash(_data):
return _data[:-10]
# Determine if the provided peer ID is valid for the provided network
#
def valid_peer(_network, _peerid):
print(' %s' % binascii.b2a_hex(_peerid))
for peer in NETWORK[_network]['PEERS']:
print(binascii.b2a_hex(peer['RADIO_ID']))
if peer['RADIO_ID'] == _peerid:
return True
return True #MUST BE FIXED!!!!!! should return false, but there are other issues right now...
# Determine if the provided master ID is valid for the provided network
#
def valid_master(_network, _peerid):
if NETWORK[_network]['MASTER']['RADIO_ID'] == _peerid:
return True
else:
return False
# Take a packet to be SENT, calcualte auth hash and return the whole thing
#
def hashed_packet(_key, _data):
hash = binascii.a2b_hex((hmac.new(_key,_data,hashlib.sha1)).hexdigest()[:20])
return (_data + hash)
# Take a RECEIVED packet, calculate the auth hash and verify authenticity
#
def validate_auth(_key, _data):
_log = logger.debug
_payload = _data[:-10]
_hash = _data[-10:]
_chk_hash = binascii.a2b_hex((hmac.new(_key,_payload,hashlib.sha1)).hexdigest()[:20])
if _chk_hash == _hash:
_log(' AUTH: Valid - Payload: %s, Hash: %s', binascii.b2a_hex(_payload), binascii.b2a_hex(_hash))
return True
else:
_log(' AUTH: Invalid - Payload: %s, Hash: %s', binascii.b2a_hex(_payload), binascii.b2a_hex(_hash))
return False
# Take a recieved peer list and the network it belongs to, process and populate the
# data structure in my_ipsc_config with the results.
#
def process_peer_list(_data, _network):
_log = logger.debug
NETWORK[_network]['MASTER']['STATUS']['PEER-LIST'] = True
_num_peers = int(str(int(binascii.b2a_hex(_data[5:7]), 16))[1:])
NETWORK[_network]['LOCAL']['NUM_PEERS'] = _num_peers
_log('<<- (%s) The Peer List has been Received from Master\n%s \
There are %s peers in this IPSC Network', _network, (' '*(len(_network)+7)), _num_peers)
del NETWORK[_network]['PEERS'][:]
for i in range(7, (_num_peers*11)+7, 11):
hex_radio_id = (_data[i:i+4])
hex_address = (_data[i+4:i+8])
hex_port = (_data[i+8:i+10])
hex_mode = (_data[i+10:i+11])
decoded_mode = mode_decode(hex_mode)
NETWORK[_network]['PEERS'].append({
'RADIO_ID': hex_radio_id,
'IP': socket.inet_ntoa(hex_address),
'PORT': int(binascii.b2a_hex(hex_port), 16),
'MODE': hex_mode,
'PEER_OPER': decoded_mode[0],
'PEER_MODE': decoded_mode[1],
'TS1_LINK': decoded_mode[2],
'TS2_LINK': decoded_mode[3],
'STATUS': {'CONNECTED': False, 'KEEP_ALIVES_SENT': 0, 'KEEP_ALIVES_MISSED': 0, 'KEEP_ALIVES_OUTSTANDING': 0}
})
# Given a mode byte, decode the functions and return a tuple of results
#
def mode_decode(_mode):
_log = logger.debug
_mode = int(binascii.b2a_hex(_mode), 16)
link_op = _mode & PEER_OP_MSK
link_mode = _mode & PEER_MODE_MSK
ts1 = _mode & IPSC_TS1_MSK
ts2 = _mode & IPSC_TS2_MSK
# Determine whether or not the peer is operational
if link_op == 0b01000000:
_peer_op = True
elif link_op == 0b00000000:
_peer_op = False
else:
_peer_op = False
# Determine the operational mode of the peer
if link_mode == 0b00000000:
_peer_mode = 'NO_RADIO'
elif link_mode == 0b00010000:
_peer_mode = 'ANALOG'
elif link_mode == 0b00100000:
_peer_mode = 'DIGITAL'
else:
_peer_node = 'NO_RADIO'
# Determine whether or not timeslot 1 is linked
if ts1 == 0b00001000:
_ts1 = True
else:
_ts1 = False
# Determine whether or not timeslot 2 is linked
if ts2 == 0b00000010:
_ts2 = True
else:
_ts2 = False
# Return a tuple with the decoded values
return _peer_op, _peer_mode, _ts1, _ts2
# Gratuituous print-out of the peer list.. Pretty much debug stuff.
#
def print_peer_list(_network):
_log = logger.info
if not NETWORK[_network]['PEERS']:
_log('\tNo peer list yet for: %s', _network)
return
_log('\tPeer List for: %s', _network)
for dictionary in NETWORK[_network]['PEERS']:
_log('\tIP Address: %s:%s', dictionary['IP'], dictionary['PORT'])
_log('\tRADIO ID: %s ', int(binascii.b2a_hex(dictionary['RADIO_ID']), 16))
_log('\tIPSC Mode:')
_log('\t\tPeer Operational: %s', dictionary['PEER_OPER'])
_log('\t\tPeer Mode: %s', dictionary['PEER_MODE'])
_log('\t\tPeer TS1 Linked: %s', dictionary['TS1_LINK'])
_log('\t\tPeer TS2 Linked: %s', dictionary['TS2_LINK'])
_log('\tConnection Status: %s', dictionary['STATUS']['CONNECTED'])
_log('\tKeepAlives Sent: %s', dictionary['STATUS']['KEEP_ALIVES_SENT'])
_log('\tKeepAlives Outstanding: %s', dictionary['STATUS']['KEEP_ALIVES_OUTSTANDING'])
_log('\tKeepAlives Missed: %s', dictionary['STATUS']['KEEP_ALIVES_MISSED'])
_log('\n')
#************************************************
#******** ***********
#******** IPSC Network 'Engine' ***********
#******** ***********
#************************************************
#************************************************
# INITIAL SETUP of IPSC INSTANCE
#************************************************
class IPSC(DatagramProtocol):
# Modify the initializer to set up our environment and build the packets
# we need to maitain connections
#
def __init__(self, *args, **kwargs):
if len(args) == 1:
# Housekeeping: create references to the configuration and status data for this IPSC instance.
# Some configuration objects that are used frequently and have lengthy names are shortened
# such as (self._master_sock) expands to (self._config['MASTER']['IP'], self._config['MASTER']['PORT'])
#
self._network = args[0]
self._config = NETWORK[self._network]
#
self._local = self._config['LOCAL']
self._local_stat = self._local['STATUS']
self._local_id = self._local['RADIO_ID']
#
self._master = self._config['MASTER']
self._master_stat = self._master['STATUS']
self._master_sock = self._master['IP'], self._master['PORT']
#
self._peers = self._config['PEERS']
args = ()
# Packet 'constructors' - builds the necessary control packets for this IPSC instance
#
self.TS_FLAGS = (self._local['MODE'] + self._local['FLAGS'])
self.MASTER_REG_REQ_PKT = (MASTER_REG_REQ + self._local_id + self.TS_FLAGS + IPSC_VER)
self.MASTER_ALIVE_PKT = (MASTER_ALIVE_REQ + self._local_id + self.TS_FLAGS + IPSC_VER)
self.PEER_LIST_REQ_PKT = (PEER_LIST_REQ + self._local_id)
self.PEER_REG_REQ_PKT = (PEER_REG_REQ + self._local_id + IPSC_VER)
self.PEER_REG_REPLY_PKT = (PEER_REG_REPLY + self._local_id + IPSC_VER)
self.PEER_ALIVE_REQ_PKT = (PEER_ALIVE_REQ + self._local_id + self.TS_FLAGS)
self.PEER_ALIVE_REPLY_PKT = (PEER_ALIVE_REPLY + self._local_id + self.TS_FLAGS)
self._peer_list_new = False
else:
# If we didn't get called correctly, log it!
#
logger.error('(%s) Unexpected arguments found.', self._network)
# This is called by REACTOR when it starts, We use it to set up the timed
# loop for each instance of the IPSC engine
#
def startProtocol(self):
# Timed loop for IPSC connection establishment and maintenance
# Others could be added later for things like updating a Web
# page, etc....
#
self._call = task.LoopingCall(self.timed_loop)
self._loop = self._call.start(self._local['ALIVE_TIMER'])
#************************************************
# FUNCTIONS FOR IPSC Network Engine
#************************************************
#************************************************
# TIMED LOOP - MY CONNECTION MAINTENANCE
#************************************************
def timed_loop(self):
logger.debug('timed loop started') # temporary debugging to make sure this part runs
print_peer_list(self._network)
_master_connected = self._master_stat['CONNECTED']
_peer_list_rx = self._master_stat['PEER-LIST']
if (_master_connected == False):
reg_packet = hashed_packet(self._local['AUTH_KEY'], self.MASTER_REG_REQ_PKT)
self.transport.write(reg_packet, (self._master_sock))
logger.debug('->> (%s) Master Registration Request To:%s From:%s', self._network, self._master_sock, binascii.b2a_hex(self._local_id))
elif (_master_connected == True):
master_alive_packet = hashed_packet(self._local['AUTH_KEY'], self.MASTER_ALIVE_PKT)
self.transport.write(master_alive_packet, (self._master_sock))
logger.debug('->> (%s) Master Keep-alive %s Sent To:%s', self._network, self._master_stat['KEEP_ALIVES_SENT'], self._master_sock)
self._master_stat['KEEP_ALIVES_SENT'] += 1
if (self._master_stat['KEEP_ALIVES_OUTSTANDING']) > 0:
self._master_stat['KEEP_ALIVES_MISSED'] += 1
if self._master_stat['KEEP_ALIVES_OUTSTANDING'] >= self._local['MAX_MISSED']:
self._master_stat['CONNECTED'] = False
logger.error('Maximum Master Keep-Alives Missed -- De-registering the Master')
else:
logger.error('->> (%s) Master in UNKOWN STATE:%s:%s', self._network, self._master_sock)
if ((_master_connected == True) and (_peer_list_rx == False)):
peer_list_req_packet = hashed_packet(self._local['AUTH_KEY'], self.PEER_LIST_REQ_PKT)
self.transport.write(peer_list_req_packet, (self._master_sock))
logger.debug('->> (%s) List Reqested from Master:%s', self._network, self._master_sock)
# Logic problems in the next if.... bad ones. Fix them.
if (_peer_list_rx == True):
for peer in (self._peers):
if (peer['RADIO_ID'] == self._local_id): # We are in the peer-list, but don't need to talk to ourselves
continue
if peer['STATUS']['CONNECTED'] == False:
peer_reg_packet = hashed_packet(self._local['AUTH_KEY'], self.PEER_REG_REQ_PKT)
self.transport.write(peer_reg_packet, (peer['IP'], peer['PORT']))
logger.debug('->> (%s) Peer Registration Request To:%s:%s From:%s', self._network, peer['IP'], peer['PORT'], binascii.b2a_hex(self._local_id))
elif peer['STATUS']['CONNECTED'] == True:
peer_alive_req_packet = hashed_packet(self._local['AUTH_KEY'], self.PEER_ALIVE_REQ_PKT)
self.transport.write(peer_alive_req_packet, (peer['IP'], peer['PORT']))
logger.debug('->> (%s) Peer Keep-Alive Request To:%s:%s From:%s', self._network, peer['IP'], peer['PORT'], binascii.b2a_hex(self._local_id))
peer['STATUS']['KEEP_ALIVES_SENT'] += 1
if peer['STATUS']['KEEP_ALIVES_OUTSTANDING'] > 0:
peer['STATUS']['KEEP_ALIVES_MISSED'] += 1
if peer['STATUS']['KEEP_ALIVES_OUTSTANDING'] >= self._local['MAX_MISSED']:
peer['STATUS']['CONNECTED'] = False
logger.error('Maximum Peer Keep-Alives Missed -- De-registering the Peer')
logger.debug('(%s) timed loop finished', self._network) # temporary debugging to make sure this part runs
#************************************************
# RECEIVED DATAGRAM - ACT IMMEDIATELY!!!
#************************************************
# Work in progress -- at the very least, notify we have the packet. Ultimately
# call a function or process immediately if only a few actions
#
def datagramReceived(self, data, (host, port)):
logger.debug('received %r from %s:%d', binascii.b2a_hex(data), host, port)
_packettype = data[0:1]
_peerid = data[1:5]
_dec_peerid = int(binascii.b2a_hex(_peerid), 16)
if validate_auth(self._local['AUTH_KEY'], data) == False:
logger.warning('(%s) AuthError: IPSC packet failed authentication. Type %s: Peer ID: %s', self._network, binascii.b2a_hex(_packettype), _dec_peerid)
return
if self._master_stat['CONNECTED'] == True:
if valid_peer(self._network, _peerid) == False or valid_master(self._network, _peerid) == False:
logger.warning('(%s) PeerError: Peer not in peer-list: %s', self._network, _dec_peerid)
return
if (_packettype == PEER_ALIVE_REQ):
logger.debug('<<- (%s) Peer Keep-alive Request From Peer ID %s at:%s:%s', self._network, _dec_peerid, host, port)
peer_alive_reply_packet = hashed_packet(self._local['AUTH_KEY'], self.PEER_ALIVE_REPLY_PKT)
self.transport.write(peer_alive_reply_packet, (host, port))
logger.debug('->> (%s) Peer Keep-alive Reply sent To:%s:%s', self._network, host, port)
elif (_packettype == MASTER_ALIVE_REPLY):
logger.debug('<<- (%s) Master Keep-alive Reply From: %s \t@ IP: %s:%s', self._network, _dec_peerid, host, port)
#### increment keep-alive outstanding here
elif (_packettype == PEER_ALIVE_REPLY):
logger.debug('<<- (%s) Peer Keep-alive Reply From: %s \t@ IP: %s:%s', self._network, _dec_peerid, host, port)
#### increment keep-alive outstanding here
elif (_packettype == MASTER_REG_REQ):
logger.debug('<<- (%s) Master Registration Packet Recieved', self._network)
elif (_packettype == MASTER_REG_REPLY):
self._master['RADIO_ID'] = _peerid
self._master_stat['CONNECTED'] = True
self._master_stat['KEEP_ALIVES_OUTSTANDING'] = 0
logger.debug('<<- (%s) Master Registration Reply From:%s:%s ', self._network, host, port)
elif (_packettype == PEER_REG_REQ):
logger.debug('<<- (%s) Peer Registration Request From Peer ID %s at:%s:%s', self._network, _dec_peerid, host, port)
peer_reg_reply_packet = hashed_packet(self._local['AUTH_KEY'], self.PEER_REG_REPLY_PKT)
self.transport.write(peer_reg_reply_packet, (host, port))
logger.debug('->> (%s) Peer Registration Reply Sent To:%s:%s', self._network, host, port)
elif (_packettype == PEER_REG_REPLY):
logger.debug('<<- (%s) Peer Registration Reply From: %s \t@ IP: %s:%s', self._network, _dec_peerid, host, port)
for peer in self._config['PEERS']:
if peer['RADIO_ID'] == _peerid:
peer['STATUS']['CONNECTED'] = True
elif (_packettype == XCMP_XNL):
logger.debug('<<- (%s) XCMP_XNL From:%s:%s, but we did not indicate XCMP capable!', self._network, host, port)
elif (_packettype == PEER_LIST_REPLY):
process_peer_list(data, self._network)
elif (_packettype == GROUP_VOICE):
logger.debug('<<- (%s) Group Voice Packet From:%s:%s', self._network, host, port)
elif (_packettype == PVT_VOICE):
logger.debug('<<- (%s) Voice Packet From:%s:%s', self._network, host, port)
elif (_packettype == GROUP_DATA):
logger.debug('<<- (%s) Group Data Packet From:%s:%s', self._network, host, port)
elif (_packettype == PVT_DATA):
logger.debug('<<- (%s) Private Data Packet From From:%s:%s', self._network, host, port)
elif (_packettype == RPT_WAKE_UP):
logger.debug('<<- (%s) Repeater Wake-Up Packet From:%s:%s', self._network, host, port)
elif (_packettype == DE_REG_REQ):
logger.debug('<<- (%s) Peer De-Registration Request From:%s:%s', self._network, host, port)
elif (_packettype == DE_REG_REPLY):
logger.debug('<<- (%s) Peer De-Registration Reply From:%s:%s', self._network, host, port)
elif (_packettype in (CALL_CTL_1, CALL_CTL_2, CALL_CTL_3)):
logger.debug('<<- (%s) Call Control Packet From:%s:%s', self._network, host, port)
else:
packet_type = binascii.b2a_hex(_packettype)
logger.error('<<- (%s) Received Unprocessed Type %s From:%s:%s', self._network, packet_type, host, port)
#************************************************
# MAIN PROGRAM LOOP STARTS HERE
#************************************************
if __name__ == '__main__':
for ipsc_network in NETWORK:
if (NETWORK[ipsc_network]['LOCAL']['ENABLED']):
reactor.listenUDP(NETWORK[ipsc_network]['LOCAL']['PORT'], IPSC(ipsc_network))
reactor.run()
Reference in New Issue View Git Blame Copy Permalink