def cksum(self, ip, data="", nx=0):
"""Calculate checksum over TCP v6 segment outside of a chain."""
total = 0
p6 = pseudoipv6()
p6.src = ip.src
p6.dst = ip.dst
p6.length = len(self.getbytes()) + len(data)
if nx:
p6.next_header = nx
else:
p6.next_header = ip.next_header
pkt = p6.getbytes() + self.getbytes() + data
return ipv4.ipv4_cksum(pkt)
def cksum(self, ip, data = "", nx = 0):
"""Calculate checksum over TCP v6 segment outside of a chain."""
total = 0
p6 = pseudoipv6()
p6.src = ip.src
p6.dst = ip.dst
p6.length = len(self.getbytes()) + len (data)
if nx:
p6.next_header = nx
else:
p6.next_header = ip.next_header
pkt = p6.getbytes() + self.getbytes() + data
return ipv4.ipv4_cksum(pkt)
def calc_checksum(self):
"""Calculate and store the checksum for this TCP v6 segment.
The packet must be part of a chain.
To do this we need to use an overlay, and copy some
header fields from the encapsulating IPv6 header."""
self.checksum = 0
if self._head is not None:
payload = self._head.collate_following(self)
ip6 = self._head.find_preceding(self, pcs.packets.ipv6)
assert ip6 is not None, "No preceding IPv6 header."
pip6 = pseudoipv6()
pip6.src = ip.src
pip6.dst = ip.dst
pip6.next_header = ip6.next_header
pip6.length = len(self.getbytes()) + len(payload)
tmpbytes = pip6.getbytes() + self.getbytes() + payload
else:
tmpbytes = self.bytes
self.checksum = ipv4.ipv4_cksum(tmpbytes)
def calc_checksum(self):
"""Calculate and store the checksum for this TCP v6 segment.
The packet must be part of a chain.
To do this we need to use an overlay, and copy some
header fields from the encapsulating IPv6 header."""
self.checksum = 0
if self._head is not None:
payload = self._head.collate_following(self)
ip6 = self._head.find_preceding(self, pcs.packets.ipv6)
assert ip6 is not None, "No preceding IPv6 header."
pip6 = pseudoipv6()
pip6.src = ip.src
pip6.dst = ip.dst
pip6.next_header = ip6.next_header
pip6.length = len(self.getbytes()) + len(payload)
tmpbytes = pip6.getbytes() + self.getbytes() + payload
else:
tmpbytes = self.bytes
self.checksum = ipv4.ipv4_cksum(tmpbytes)
