Trouble compiling the decrypt sample...

movax · Post by **movax** » Wed Jan 03, 2007 3:07 pm

Hey all, I'm in the process of writing a PSX <-> PSP savegame converter (Standalone from CWCheat), and I'm having trouble using the decrypt sample...

I can compile it just fine (using cygwin environment under WinXP), get the .PBP & .SFO, but it will not run on the PSP (Black screen). Removing the portions of the code that depend on the "-lpspsvchnnl" in the Makefile allows it to run (I stuck a test printf("test") at the beginning of the main loop, and it appeared).

PSP was a 1.5 flashed to the 3.02 OE-B (please tell me that doesn't cuase problems...?), and I've been attempting runs under the GAME150 (1.5 fw) folder. Something wrong on the PSP's end, or PC end?

adrahil · Post by **adrahil** » Wed Jan 03, 2007 3:45 pm

Homebrew chnnlsv save game support is broken right now in 3.x

movax · Post by **movax** » Wed Jan 03, 2007 4:04 pm

Broken eh? Leads me to two questions, 1. seems like there are tools that are still using that under 3.xx, and 2. I thought the point of OE-B was to allow homebrew to run under the 1.5 kernel by being placed in the GAME150 directory?

pspwill · Post by **pspwill** » Wed Jan 03, 2007 10:46 pm

Didnt the savedata samples only work on 2.X under eloader?

Fanjita · Post by **Fanjita** » Thu Jan 04, 2007 4:43 am

Correct, the necessary API is only available in VSH mode.

Presumably you could fairly easily load the required module from v1.5-style homebrew if you wanted to, though.

And I seem to recall someone was once going to reverse engineer the ChnnlSv functions and port them to something usable from game mode, but I don't remember who, and I don't believe they ever finished it.

movax · Post by **movax** » Thu Jan 04, 2007 8:49 am

VSH mode? Forgive me, I just got my PSP less than a month ago and am trying to readup all the homebrew tuts I can. :) Got basic text I/O down, inputs & stuff, was hoping to move on now, heh.

Fanjita · Post by **Fanjita** » Thu Jan 04, 2007 11:05 am

The PSP can boot into 3 basic modes : VSH, Updater and Game.

VSH is what is running when the XMB is active, and so it is the mode that exploits based on TIFF etc. end up in.

Game is what the PSP kernel launches UMDs in, and EBOOTs, if you manage to coax it into loading an EBOOT by itself.

The different modes have different sets of modules loaded by default. The decryption sample happens to need the ChnnlSv API, which is loaded (by default) under VSH only. Hence, it won't work outside of the TIFF exploit, without some additional effort.

movax · Post by **movax** » Thu Jan 04, 2007 2:53 pm

Ah, thanks for the clarification/explanations of modes.

Is there a tutorial that lists these different modes, or how to use certain exploits to execute homebrew code?

Fanjita · Post by **Fanjita** » Thu Jan 04, 2007 9:43 pm

Not as far as I know.

For running code via the TIFF exploit, you can grab the TIFF SDK from www.noobz.eu, it does most of the work for you.