def decodePhyPayload(msg, AppSKey, DevAddr):
# extract the physical payload from the message
# and convert to hex
char_seq = "phyPayload"
idx = msg.payload.rfind(char_seq) + 13
PHYPayload = msg.payload[idx:-2]
PHYPayload = base64.decodestring(PHYPayload).encode('hex')
# extract the MAC payload
MACPayload = PHYPayload[2:-8]
# decode the MAC payload
DevAddr = flipEndianess(MACPayload[0:8])
FOptsLen = int(MACPayload[9], 16)
FCnt = int(flipEndianess(MACPayload[10:14]), 16)
FRMPayload = MACPayload[14 + 2 * FOptsLen + 2:]
# decrypt the FRM payload
payload = loramac_decrypt(FRMPayload, FCnt, AppSKey, DevAddr)
# convert to hex
payload_int = 0
byte_num = len(payload) - 1
for byte in payload:
payload_int += int(byte) * 2**(8 * byte_num)
byte_num -= 1
print format(payload_int, '#04x')
def lorawan_points_all(request):
''' All LoRaWAN raw points, but try to decrypt them '''
out = {'points': []}
for point in LoRaWANRawPoint.objects.all().order_by('-id')[:1000]:
p = {}
p['id'] = point.id
p['FRMPayload'] = point.FRMPayload
p['FCnt'] = point.FCnt
p['FPort'] = point.FPort
p['DevAddr'] = point.DevAddr
MTypes = (
'Join Request',
'Join Accept',
'Unconfirmed Data Up',
'Unconfirmed Data Down',
'Confirmed Data Up',
'Confirmed Data Down',
'RFU',
'Proprietary',
)
if point.MType:
p['MType_description'] = MTypes[point.MType]
else:
pass
try:
# LoRaWAN spec 1.0; section 4.3.3.1
if point.FPort == 0:
SKey = point.node.lorawan_NwkSKey
p['SKey_used'] = 'NwkSKey'
p['NwkSKey'] = point.node.lorawan_NwkSKey
else:
SKey = point.node.lorawan_AppSKey
p['SKey_used'] = 'AppSKey'
p['AppSKey'] = point.node.lorawan_AppSKey
FRMPayload_decrypted = ""
FRMPayload_decrypted = loramac_decrypt(point.FRMPayload,
point.FCnt, SKey,
point.DevAddr)
p['FRMPayload_decrypted'] = "".join("{:02x}".format(c)
for c in FRMPayload_decrypted)
except Exception as e:
p['error'] = "Unable to decrypt LoRaWAN packet " + str(e)
out['points'].append(p)
pretty_json = json.dumps(out, indent=4)
response = HttpResponse(pretty_json, content_type="application/json")
response['Access-Control-Allow-Origin'] = '*'
return response
def test_loramac_decrypt(self):
key = "271E403DF4225EEF7E90836494A5B345"
dev_addr = "000015E4"
payloads = ((0, "73100b90"), (1, "68d388f0"), (2, "0a12e808"), (3, "e3413bee"))
expected = "cafebabe"
for sequence_counter, payload_hex in payloads:
plaintext_ints = loramac_decrypt(payload_hex, sequence_counter, key, dev_addr)
plaintext_hex = "".join("{:02x}".format(x) for x in plaintext_ints)
self.assertEquals(plaintext_hex, expected)
def test_loramac_decrypt(self):
key = "271E403DF4225EEF7E90836494A5B345"
dev_addr = "000015E4"
payloads = ((0, "73100b90"), (1, "68d388f0"), (2, "0a12e808"),
(3, "e3413bee"))
expected = "cafebabe"
for sequence_counter, payload_hex in payloads:
plaintext_ints = loramac_decrypt(payload_hex, sequence_counter,
key, dev_addr)
plaintext_hex = "".join("{:02x}".format(x) for x in plaintext_ints)
self.assertEquals(plaintext_hex, expected)
def test_loramac_decrypt(self):
key = '271E403DF4225EEF7E90836494A5B345'
dev_addr = '000015E4'
payloads = (
(0, '73100b90'),
(1, '68d388f0'),
(2, '0a12e808'),
(3, 'e3413bee'),
)
expected = 'cafebabe'
for sequence_counter, payload_hex in payloads:
plaintext_ints = loramac_decrypt(payload_hex, sequence_counter, key, dev_addr)
plaintext_hex = ''.join('{:02x}'.format(x) for x in plaintext_ints)
self.assertEquals(plaintext_hex, expected)
from lora.crypto import loramac_decrypt
import base64
x = (base64.b64decode('QESufgGAAAABizI7/Kupf6U='))
payload = x
key = '283EFC8ED5A378712420CE8568A461D3'
sequence_counter = 2
dev_addr = '017EAE44'
print(loramac_decrypt(payload, sequence_counter, key, dev_addr))
#283EFC8ED5A378712420CE8568A461D3
#593AE59422E01E88ED8FF9584B632C89
#514553756667474141414142697a49372f4b75706636553d
#514553756667474141414142697a49372f4b75706636553d
#QESufgGAAAABizI7/Kupf6U=
#247, 28, 213, 236, 58, 52, 99, 66, 128, 157, 71, 44, 18, 145, 99, 223, 147, 159, 88, 182, 186, 204, 168, 255
pprint(d)
info['PHYPayload'] = []
for c in base64.decodestring(d):
info['PHYPayload'].append(ord(c))
info['MIC'] = info['PHYPayload'][-4:]
info['MHDR'] = info['PHYPayload'][0]
info['MACPayload'] = info['PHYPayload'][1:]
info['MACPayload'] = info['MACPayload'][:-4]
info['FPort'] = info['MACPayload'][7]
info['FRMPayload'] = info['MACPayload'][8:]
info['FHDR'] = info['MACPayload'][:7]
info['DevAddr'] = "".join("{:02x}".format(info['FHDR'][c]) for c in range(3,-1,-1))
info['FCnt'] = struct.unpack("<H", "".join(chr(c) for c in info['FHDR'][5:7]))[0]
info['FCtrl'] = info['FHDR'][4]
info['FCtrl_bin'] = bin(info['FCtrl'])
payload = ''.join("{:02x}".format(c) for c in info['FRMPayload'])
if args.verbose:
print("Will try to decode the FRMPayload payload " + payload)
key = '820EB5127B0B98C8CC0B7EE43253E0D1'
out = loramac_decrypt(payload, info['FCnt'], key, info['DevAddr'])
info['decrypted_payload'] = out
if args.verbose:
pprint(info)
def decrypt(self, Appskey):
return loramac_decrypt(self.FRMPayload, self.FCnt, Appskey,
self.DevAddr, 0)
bDevAddr=bytes(_DevAddr)
SDevAddr=DevAddr.decode(encoding="utf-8")
FCTR=frame[10:12]
FCNT=frame[14:16]+frame[12:14]
FPORT=frame[16:18]
Payload = frame[18:-8]
MIC= frame[-8:]
data= loramac_decrypt(Payload,int(FCNT,16),key,SDevAddr)
hexData =""
for x in data:
if(x < 16):
hexData+= '0'
hexData+= hex(x)
else:
hexData+= hex(x)
hexData=hexData.replace('0x','')
#hexData=''.join(hex(x) for x in data).replace('0x','').upper()
print("MHDR: ",MHDR,"\nDevAddr: ",SDevAddr,"\nFCTR: ",FCTR,"\nFCNT: ",FCNT,"\nFPORT: ",FPORT,"\nPayload: ",Payload,"\nMIC: ",MIC)