Multiplayer ( Structure of UDP Packets )

[diegocn 0]

Hi, first of all, sorry for my bad english...

Iam trying to create a persistent world server for OFP Res.

But in this point, with help of people who devolphed monitoring server and others, I have a basic program with responses from de server.

Example, the packet sent from server to client to list the session on the server:

<table border="0" align="center" width="95%" cellpadding="0" cellspacing="0"><tr><td>Code Sample </td></tr><tr><td id="CODE">178 001 001 008 223 254 052 098 001 000 000 000 001 000 000 000 000 000 000 000 000 000 000 000 172 232 241 255 084 101 115 116 101 032 111 110 032 100 105 101 103 111 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 196 000 000 000 195 000 000 000 068 101 097 116 104 109 097 116 099 104 032 040 049 045 056 032 068 041 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 006 000 000 000 000 000 000 000 000 000 254 008 000 000 000 000 090 016 000 000 082 069 083 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000

The two first bytes are a double integer that represt the size of the packet. The 9 and 10 byte, are a double integer that increase one at each pack. In the 29 byte is the string "teste on diego" that is the name of the player and the name of the machine that server are running.

All ok, BUT wait, the bytes 5, 6, 7 and 8, seems to be a checksum to the packet. The server and client accept and

answer the packet if not modified ( no utility in this ), i need to know the algoritim of the checksum...

Anyone can help-me?!

Thanks very much,

Diego

[zaphar 0]

you may be asking in the wrong area of this forum, most people probably don't know what you're talking about in here. You may want to go to the mod section or something, but I like your idea, I would love to see something like it. I imagine that ofp watch messed around with the same stuff.

[diegocn 0]

Ok, thankyou ;]

Admin, please disconsider the double post...

Diego

[sicilian 0]

I doubt there's anyone who knows about the checksum because then we all were able to modify packets which the checksum should prevent... So don't wait too long for an positive answer.

[crashdome 3]

On top of what sicilian said,

you could just wait for Armed Assault to be released (what is it? in a few months maybe?) and save yourself a whole heap o'work since it will allow for join-in-progress.

In the meantime, check out our campaign missions which allow saving of certain things (like the SP resistance campaign) between missions. (It even saves your loadout between missions) and we didn't do any packet-sniffing

Link to Thread: http://www.flashpoint1985.com/cgi-bin....ar;st=0

You'll find the NEW downloads section here (one in thread is removed):

http://www.sinewsofwar.com/Downloads/tabid/77/Default.aspx