Endians problem in TCP checksum field . last 2 byte get swaped .

umitproject · Aug 22, 2011 · 84a7f24 · 84a7f24
1 parent f56752f
commit 84a7f24
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Showing 2 changed files with 4 additions and 2 deletions.
diff --git a/umit/umpa/protocols/TCP.py b/umit/umpa/protocols/TCP.py
@@ -616,7 +616,8 @@ def _post_raw(self, raw_value, bit, protocol_container, protocol_bits):
                     pheader_raw = pheader.get_raw(protocol_container, protocol_bits)[0]
                     cksum |= pheader_raw << offset
                     raw_cksum = _net.in_cksum(cksum)
-                    cksum_cal = ((raw_cksum << 8) | (raw_cksum >> 8)) & 0xFFFF
+                    #cksum_cal = ((raw_cksum << 8) | (raw_cksum >> 8)) & 0xFFFF
+                    cksum_cal = raw_cksum
                     raw_value |= cksum_cal << cksum_rev_offset
                 elif isinstance(proto, IP):
                     pheader = _layer4.PseudoHeader(self.protocol_id, total_length)

diff --git a/umit/umpa/protocols/UDP.py b/umit/umpa/protocols/UDP.py
@@ -386,7 +386,8 @@ def _post_raw(self, raw_value, bit, protocol_container, protocol_bits):
                     pheader_raw = pheader.get_raw(protocol_container, protocol_bits)[0]
                     cksum |= pheader_raw << offset
                     raw_cksum = _net.in_cksum(cksum)
-                    cksum_cal = ((raw_cksum << 8) | (raw_cksum >> 8)) & 0xFFFF
+                    #cksum_cal = ((raw_cksum << 8) | (raw_cksum >> 8)) & 0xFFFF
+                    cksum_cal = raw_cksum
                     raw_value |= cksum_cal << cksum_rev_offset
                 elif isinstance(proto, IP):
                     pheader = _layer4.PseudoHeader(self.protocol_id,self.get_field('_length').fillout())