client-server CheckSum

Hi, i’v emulate client login and select character, then join into world and in some seconds get disconnect from server. i start investigate and see this packets: c3 08 03 00 5b cf d2 11 c3 08 03 00 30 31 1f ae maybe this is checksum? do you know how to get this/create? this code capture checksum and return to client?

also next packet after is: c1 05 18 16 5f and it’s always the same

thanks.

[sven-n]

Well, when I played this game about 8 years ago, I researched a lot about the mu online protocol and game mechanics. The “mu helper” wasn’t there yet, so I developed some packet based bots 😉

You can find some informations about the client checksum here: http://forum.ragezone.com/f197/main-checksum-dat-generator-422560/ http://forum.ragezone.com/f197/multicore-checksum-dat-generator-662748/

GetIndex reverse function: https://github.com/kessiler/muOnline-season6/blob/1e331e5765e102f44c7af29b6834a6bda96fcc2b/gameServer/gameServer/protocol.cpp#L1402

[Tocher]

launcher saved me, and i connect to my proxy. and now i have interesting things.

GetIndex from 0x1d28 and 0x1d18 is 673 so Checksum 4 bytes must be similar (or i mistake) but sending this two challenge to client from my proxy give me this:

0x1d18 c3 08 03 0c c0 c7 66 98 (decrypted)

0x1d28 c3 08 03 0c a1 ee 74 47 (decrypted)

i think this server have more complicated secure, so i try get full table from 0x0001 to 0xffff and search for algorithm or so)

thx very much for your help! ❤️