TCP Retransmissions

Ordinarily, you're a terrible place to get code, /prog/, but I must yield.

I'm having trouble with AES encryption increasing on packet retransmissions, so I obviously must detect and discard retransmissions for encryption purposes. Since I'm using WinPcap, I figured that Ethereal would be a good place to go to see how it detects these events. I was wrong.

Example: http://pastebin.com/d165a8f15 ^[1]

I can't tell what the shit is going on with such ugly C code. Any of you have an enterprise-level solution to retransmission detection? Thanks for your time.

¹: As accessed on 4 JAN 09 at 10 PM CST. It will evaporate within 24 hours.

There is difference:
example JMP :
"This instruction is used to deviate the flow of a program without taking into account the actual conditions of the flags or of the data."
exmaple JA Label
"This means that the jump is only done if the CF flag is deactivated or if the ZF flag is deactivated, that is that one of the two be equal to zero."

Which one is faster?