Issue with eboot modding OGP/COP

[MimounEH]

Hi, i wanted to create a modded EBOOT for a game, i used netcheat to find the offset and i found the original adress with ps3 debugger, but now i have 2 questions/problems:

How i know the length of the OGP, for example, it can be: B13F05742F800000419E0014C01F0 or B13F05742F800 and the second question is, how i calculate the COP? if i want infinite ammo how i can calculate it? Thanks you and sorry for my broken english.

 

[stinger1011]

Depending on which alteration your attempting to apply, memory address or assembly code insertion(in example changing the script function where say the code subtracts money from your current monies to the monies after the transaction to null out that subtraction function ergo eliminating the subtraction from transactions). For assembly I think you'll need a hex to PPC instruction converter to get a hex string aka cop for what your intented modification will be. So if you nop out an instruction it will be different than say just modifying the stored values in memory at x offset which only would require you find the type 1 byte 2 byte float etc and change the value following the value type guidelines if one byte the you'll only need modify 2 bits of memory at the found address of whatever value you searched for. If a value is padded with zero bits the value you write may be somthin 1ike this 000000FF or 255 in dec, others may require you to pad the value differently for example sonic adventure the values are stored for rings and lives in memory 00XX0000 so if you apply the value 000000FF it will appear in game as you don't have any of whatever item ammo money cuz you wrote zeros over the actual value XX, so you would need to adjust your padding on that 8bit hexideimal number to say 00FF000000. I give sonic adventure as an example as the current netcheat codes are all 000000XX when the game uses the layout 00XX0000 for rings lives etc. I had to fix these values after peeking at the cheats address to see the change in value as I collected stuff to know where I needed to put my modified XX in order for the game to actually recognize the modified values.

 

[stinger1011]

Essentially if you already have the ogp cop for your intended cheat all you need to do is use true ancestors or a likewise tool, decrype the eboot.bin to eboot.elf open the elf in a hex editor search for a hex string in all directions for the ogp, if found overwrite the ogp with cop, repeat for all desired cheats, save the modified elf go back to true ancestors and encrypt the elf to a bin, if it's a psn game use the npdrm option otherwise your game won't launch.