def parse(self, raw):
assert isinstance(raw, bytes)
self.raw = raw
dlen = len(raw)
if dlen < gre.MIN_LEN:
self.msg('warning GRE packet data too short to ' +
'parse header: data len %u' % (dlen, ))
return
o = 0
flags, self.type = struct.unpack("!HH", raw[o:o + 4])
o += 4
self.ver = flags & 7
if self.ver != 0:
self.msg('unknown GRE version: %s' % (self.ver, ))
csum_present = (flags & 0x8000) != 0
route_present = (flags & 0x4000) != 0
key_present = (flags & 0x2000) != 0
seq_present = (flags & 0x1000) != 0
self.strict_source_route = (flags & 0x800) != 0
self.recursion = (flags & 0x700) >> 8
offset = None
if csum_present or route_present:
self.csum, self.route_offset = struct.unpack("!HH", raw[o:o + 4])
o += 4
if self.verify_csum:
if checksum(raw) != 0:
self.msg('warning GRE checksum did not match')
return
if key_present:
self.key = struct.unpack("!I", raw[o:o + 4])[0]
o += 4
if seq_present:
self.seq = struct.unpack("!I", raw[o:o + 4])[0]
o += 4
if route_present:
self.routing = []
while True:
af, so, sl = struct.unpack("!HBB", raw[o:o + 4])
o += 4
sd = raw[o:o + sl]
o += sl
self.routing.append((af, so, sl, sd))
if sl == 0: break
self.parsed = True
if self.type == 0x0800:
self.next = ipv4.ipv4(raw=raw[o:])
elif self.type == 0x6558:
self.next = ethernet(raw=raw[o:])
else:
self.next = raw[o:]
def parse(self):
dlen = len(self.arr)
if dlen < self.MIN_LEN:
print '(unreach parse) warning unreachable payload too short to parse header: data len %u' % dlen
return
(self.unused, self.next_mtu) \
= struct.unpack('!HH', self.arr[:self.MIN_LEN])
self.parsed = True
if dlen >= 28:
# xxx We're assuming this is IPv4!
import ipv4
self.next = ipv4.ipv4(arr=self.arr[unreach.MIN_LEN:],prev=self)
else:
self.next = self.arr[unreach.MIN_LEN:].tostring()
def parse(self):
dlen = len(self.arr)
if dlen < self.MIN_LEN:
print '(unreach parse) warning unreachable payload too short to parse header: data len %u' % dlen
return
(self.unused, self.next_mtu) \
= struct.unpack('!HH', self.arr[:self.MIN_LEN])
self.parsed = True
if dlen >= 28:
# xxx We're assuming this is IPv4!
import ipv4
self.next = ipv4.ipv4(arr=self.arr[unreach.MIN_LEN:], prev=self)
else:
self.next = self.arr[unreach.MIN_LEN:].tostring()
def parse (self, raw):
assert isinstance(raw, bytes)
self.raw = raw
dlen = len(raw)
if dlen < self.MIN_LEN:
self.msg('(time_exceeded parse) warning payload too short '
'to parse header: data len %u' % (dlen,))
return
self.unused = struct.unpack('!I', raw[:self.MIN_LEN])[0]
self.parsed = True
if dlen >= 28:
# xxx We're assuming this is IPv4!
import ipv4
self.next = ipv4.ipv4(raw=raw[self.MIN_LEN:],prev=self)
else:
self.next = raw[self.MIN_LEN:]
def parse(self, raw):
assert isinstance(raw, bytes)
self.raw = raw
dlen = len(raw)
if dlen < self.MIN_LEN:
self.msg("(unreach parse) warning unreachable payload too short to parse header: data len %u" % dlen)
return
(self.unused, self.next_mtu) = struct.unpack("!HH", raw[: self.MIN_LEN])
self.parsed = True
if dlen >= 28:
# xxx We're assuming this is IPv4!
import ipv4
self.next = ipv4.ipv4(raw=raw[unreach.MIN_LEN :], prev=self)
else:
self.next = raw[unreach.MIN_LEN :]
def parse(self, raw):
assert isinstance(raw, bytes)
self.raw = raw
dlen = len(raw)
if dlen < self.MIN_LEN:
self.msg('(time_exceeded parse) warning payload too short '
'to parse header: data len %u' % (dlen, ))
return
self.unused = struct.unpack('!I', raw[:self.MIN_LEN])[0]
self.parsed = True
if dlen >= 28:
# xxx We're assuming this is IPv4!
import ipv4
self.next = ipv4.ipv4(raw=raw[self.MIN_LEN:], prev=self)
else:
self.next = raw[self.MIN_LEN:]
def parse(self, raw):
assert isinstance(raw, bytes)
self.raw = raw
dlen = len(raw)
if dlen < self.MIN_LEN:
self.msg('(unreach parse) warning unreachable payload too short '
'to parse header: data len %u' % dlen)
return
(self.unused, self.next_mtu) \
= struct.unpack('!HH', raw[:self.MIN_LEN])
self.parsed = True
if dlen >= 28:
# xxx We're assuming this is IPv4!
import ipv4
self.next = ipv4.ipv4(raw=raw[unreach.MIN_LEN:],prev=self)
else:
self.next = raw[unreach.MIN_LEN:]
