DMRlink/bridge.py

# Copyright (c) 2013 Cortney T. Buffington, N0MJS and the K0USY Group. n0mjs@me.com
#
# This work is licensed under the Creative Commons Attribution-ShareAlike
# 3.0 Unported License.To view a copy of this license, visit
# http://creativecommons.org/licenses/by-sa/3.0/ or send a letter to
# Creative Commons, 444 Castro Street, Suite 900, Mountain View,
# California, 94041, USA.

from __future__ import print_function
from twisted.internet.protocol import DatagramProtocol
from twisted.internet import reactor
from twisted.internet import task
from binascii import b2a_hex as h

import binascii
import dmrlink
from dmrlink import IPSC, UnauthIPSC, NETWORK, networks, int_id, send_to_ipsc, dmr_nat, logger

RULES = {
    'K0USY': {
        'GROUP_VOICE': [
            {'SRC_GROUP': b'\x00\x00\x03', 'DST_NET': 'LAWRENCE', 'DST_GROUP': b'\x00\x00\x03'},
            {'SRC_GROUP': b'\x00\x0C\x30', 'DST_NET': 'LAWRENCE', 'DST_GROUP': b'\x00\x0C\x30'},
            {'SRC_GROUP': b'\x00\x0C\x30', 'DST_NET': 'TEST', 'DST_GROUP': b'\x00\x00\xD2'}
        ],
        'PRIVATE_VOICE': [
        ],
        'GROUP_DATA': [            
        ],
        'PRIVATE_DATA': [
        ]
    },
    'LAWRENCE': {
        'GROUP_VOICE': [
            {'SRC_GROUP': b'\x00\x00\x03', 'DST_NET': 'K0USY', 'DST_GROUP': b'\x00\x00\x03'},
            {'SRC_GROUP': b'\x00\x0C\x30', 'DST_NET': 'K0USY', 'DST_GROUP': b'\x00\x0C\x30'},
            {'SRC_GROUP': b'\x00\x0C\x30', 'DST_NET': 'TEST', 'DST_GROUP': b'\x00\x00\xD2'}
        ],
        'PRIVATE_VOICE': [
        ],
        'GROUP_DATA': [            
        ],
        'PRIVATE_DATA': [
        ]
    },
    'TEST': {
        'GROUP_VOICE': [
            {'SRC_GROUP': b'\x00\x00\xD2', 'DST_NET': 'K0USY', 'DST_GROUP': b'\x00\x0C\x30'},
            {'SRC_GROUP': b'\x00\x00\xD2', 'DST_NET': 'LAWRENCE', 'DST_GROUP': b'\x00\x0C\x30'}
        ],
        'PRIVATE_VOICE': [
        ],
        'GROUP_DATA': [            
        ],
        'PRIVATE_DATA': [
        ]
    }
}

class bridgeIPSC(IPSC):
      
    def __init__(self, *args, **kwargs):
        IPSC.__init__(self, *args, **kwargs)
        self.ACTIVE_CALLS = []
        
    #def datagramReceived(self, data, (host, port)):
    #    print(h(data))
        
        
    #************************************************
    #     CALLBACK FUNCTIONS FOR USER PACKET TYPES
    #************************************************
    
    def group_voice(self, _network, _src_sub, _dst_sub, _ts, _end, _peerid, _data):
        for source in RULES[_network]['GROUP_VOICE']:
            # Matching for rules is against the Destination Group in the SOURCE packet (SRC_GROUP)
            if source['SRC_GROUP'] == _dst_sub:
                _tmp_data = _data
                _target = source['DST_NET']
                # Re-Write the IPSC SRC to match the target network's ID
                _tmp_data = _tmp_data.replace(_peerid, NETWORK[_target]['LOCAL']['RADIO_ID'])
                # Re-Write the destinaion Group ID
                _tmp_data = _tmp_data.replace(_dst_sub, source['DST_GROUP'])
                # Calculate and append the authentication hash for the target network... if necessary
                if NETWORK[_target]['LOCAL']['AUTH_ENABLED'] == True:
                    _tmp_data = self.hashed_packet(NETWORK[_target]['LOCAL']['AUTH_KEY'], _tmp_data)
                # Send the packet to all peers in the target IPSC
                send_to_ipsc(_target, _tmp_data)
    
    def private_voice(self, _network, _src_sub, _dst_sub, _ts, _end, _peerid, _data): 
        pass
    
    def group_data(self, _network, _src_sub, _dst_sub, _ts, _end, _peerid, _data):    
        pass
    
    def private_data(self, _network, _src_sub, _dst_sub, _ts, _end, _peerid, _data):    
        pass
        
    def call_ctl_1(self, _network, _data):
        pass
    
    def call_ctl_2(self, _network, _data):
        pass
    
    def call_ctl_3(self, _network, _data):
        pass
    
    def xcmp_xnl(self, _network, _data):
        pass

class bridgeUnauthIPSC(bridgeIPSC):
    
    # There isn't a hash to build, so just return the data
    #
    def hashed_packet(self, _key, _data):
        return _data   
    
    # Remove the hash from a packet and return the payload... except don't
    #
    def strip_hash(self, _data):
        return _data
    
    # Everything is validated, so just return True
    #
    def validate_auth(self, _key, _data):
        return True

if __name__ == '__main__':
    logger.info('DMRlink \'bridge.py\' (c) 2013 N0MJS & the K0USY Group - SYSTEM STARTING...')
    for ipsc_network in NETWORK:
        if (NETWORK[ipsc_network]['LOCAL']['ENABLED']):
            if NETWORK[ipsc_network]['LOCAL']['AUTH_ENABLED'] == True:
                networks[ipsc_network] = bridgeIPSC(ipsc_network)
            else:
                networks[ipsc_network] = bridgeUnauthIPSC(ipsc_network)
            reactor.listenUDP(NETWORK[ipsc_network]['LOCAL']['PORT'], networks[ipsc_network])
    reactor.run()