Thank DiDA for your reply, ( I found this tut http://www.progamercity.net/ghack-tu...rsing-mmo.html useful when decrypt packet)
So I found this code - the encryption method in IDA:
1.NSDataAESDecrypt
2.NSDataAESDecryptwithkey
3.NSSStringAES256
4.NSSStringGMOAES256
5.GMOStringcryptiondecrypt
6.GMODecryptkeypadding
7.GMOSDKRSACCipherkey
8.GMOGAMESDKRSAC
9.Seccdecryptkey
And I think the packet encryption method is one of those above. So there are 2 options for me.
1.Test all the encryption method above to see what make most sense for my packet (but it's complicated)
2.Use GikDbg, and send a packet in to see what they use to decrypt it.
But when I open the GikDbg in window 7 the error 6080 port appear, I try to restart it but still error, Should I run the GikDbg in VMXPLite or not?
(https://iosgods.com/topic/2754-tutorial-how-to-use-gikdbg-lldb-for-windows/ I read the tutorial here but not quite understand it)