class BTLE(Packet):
name = "BT4LE"
fields_desc = [
XLEIntField("access_addr", 0x8E89BED6),
LEX3BytesField("crc", None)
]
@staticmethod
def compute_crc(pdu, init=0x555555):
def swapbits(a):
v = 0
if a & 0x80 != 0:
v |= 0x01
if a & 0x40 != 0:
v |= 0x02
if a & 0x20 != 0:
v |= 0x04
if a & 0x10 != 0:
v |= 0x08
if a & 0x08 != 0:
v |= 0x10
if a & 0x04 != 0:
v |= 0x20
if a & 0x02 != 0:
v |= 0x40
if a & 0x01 != 0:
v |= 0x80
return v
state = swapbits(init & 0xff) + (swapbits((init >> 8) & 0xff) << 8) + (
swapbits((init >> 16) & 0xff) << 16) # noqa: E501
lfsr_mask = 0x5a6000
for i in (orb(x) for x in pdu):
for j in range(8):
next_bit = (state ^ i) & 1
i >>= 1
state >>= 1
if next_bit:
state |= 1 << 23
state ^= lfsr_mask
return struct.pack("<L", state)[:-1]
def post_build(self, p, pay):
# Switch payload and CRC
crc = p[-3:]
p = p[:-3] + pay
p += crc if self.crc is not None else self.compute_crc(p[4:])
return p
def post_dissect(self, s):
self.raw_packet_cache = None # Reset packet to allow post_build
return s
def pre_dissect(self, s):
# move crc
return s[:4] + s[-3:] + s[4:-3]
def hashret(self):
return struct.pack("!L", self.access_addr)
class Join_Accept(Packet):
name = "Join_Accept"
dcflist = False
fields_desc = [LEX3BytesField("JoinAppNonce", 0),
LEX3BytesField("NetID", 0),
XLEIntField("DevAddr", 0),
DLsettings,
XByteField("RxDelay", 0),
ConditionalField(StrFixedLenField("CFList", b"\x00" * 16, 16), # noqa: E501
lambda pkt:(Join_Accept.dcflist is True))]
# pylint: disable=R0201
def extract_padding(self, p):
return "", p
def __init__(self, packet=""): # CFList calculated with rest of packet len
if len(packet) > 18:
Join_Accept.dcflist = True
super(Join_Accept, self).__init__(packet)
class BTLE_CONNECT_REQ(Packet):
name = "BTLE connect request"
fields_desc = [
BDAddrField("InitA", None),
BDAddrField("AdvA", None),
# LLDATA
XLEIntField("AA", 0x00),
LEX3BytesField("crc_init", 0x0),
XByteField("win_size", 0x0),
XLEShortField("win_offset", 0x0),
XLEShortField("interval", 0x0),
XLEShortField("latency", 0x0),
XLEShortField("timeout", 0x0),
BTLEChanMapField("chM", 0),
BitField("SCA", 0, 3),
BitField("hop", 0, 5),
]
class PCOMBinaryResponse(PCOMBinary):
name = "PCOM/Binary Response"
fields_desc = [
StrFixedLenField("stx", "/_OPLC", 6),
XByteField("reserved1", 0xfe),
XByteField("id", 0x0),
XByteField("reserved2", 0x1),
LEX3BytesField("reserved3", 0x0),
PCOMBinaryCommandField("command", None),
XByteField("reserved4", 0x0),
StrFixedLenField("commandSpecific", '', 6),
LEFieldLenField("len", 0, length_of="data"),
XLEShortField("headerChksum", None),
StrLenField("data", '', length_from=lambda pkt: pkt.len),
XLEShortField("footerChksum", None),
XByteField("etx", 0x5c)
]
class DevAddrElem(Packet):
name = "DevAddrElem"
fields_desc = [
XByteField("NwkID", 0x0),
LEX3BytesField("NwkAddr", b"\x00" * 3)
]
