here is what he sad for me it's true.... ( he is an software engineer and has made a reverse engineering of the psp firmware ) i really thing that an upgrade software at this moment is impossible ...

Mr.A - MaxConsole.net:

Recently we have all been exposed to a large amount of hype and rumors relating to attempts to downgrade PSP's firmware for the purpose of using homebrew software. Two groups in particular, WAB and PSP-DEV have been claiming that they have a downgrader working but as yet all we have seen from either of these groups are a bunch of faked videos - no actual information or anything else which might suggest that they actually do have something working.

I have quite a bit of experience with reverse engineering etc and have personally examined the PSP firmware upgrade procedure by decrypting the updater executable and accompanying data file so I know how it all works. If either WAB or PSP-DEV had the skills to do this then they would probably never have claimed that they could downgrade the firmware since they would know exactly what is involved and that its not possible through software alone. I will try to explain how this all works without getting too technical..

As you know, the PSP upgrades come in the form of EBOOT.PBP archive files. The archives contain the encrypted upgrade executable (DATA.PSP), the encrypted data file (DATA.PSAR) and some other information such as the firmware version which is contained in the PARAM.SFO file. The PARAM.SFO file has been the focus of many downgrade attempts, but all these attempts have been in vain. While the PSP OS does indeed use this file to get the firmware version which will be upgraded to, even if you can bypass this first check and actually get a updater running (say 1.50 updater on 1.52 system) you will still not be able to downgrade.

This is because there is yet another check inside the update executable. The version information for the firmware which will be updated to is stored alongwith the rest of the upgrade data in the DATA.PSAR file. Once you start the upgrade the version information from the DATA.PSAR file is compared with the version of the firmware your PSP is currently running. If your PSP is running a more recent version than is contained in the DATA.PSAR file then you will receive an error.
Currently it is not possible for us to encrypt our own DATA.PSAR files or executable files. So we cannot simply edit the version information in the PSAR and we cannot simply patch out the check in the updater executable. I bet now some of you are thinking why dont you just change the firmware on your PSP so its reported as 1.00, then the upgrade will work!. In order to change the firmware version you will need to be able to execute unsigned code, if this was possible then a downgrade might not even be needed at all.

I dont see a working downgrade method appearing any time soon, especially with everybody going about it the wrong way! WAB dont seem to know what they are doing and they probably think that since you guys dont know either they can feed you crap. I just hope after reading this you are a bit more educated on the subject and now the lies they feed wont stick or continue giving people false hope for something which will most probably never come (at least not from these kids ala WAB).

Yoshiro get angry with Mr.A cause he explain to people thaat doesn't know anything about PSP that the downgrade is a fake !

Here the YOshiro and Mr.A reply from MAxConsole.net:

Today, 02:31 AM
Mr-A
Registered User Registered: Sep 2005
Posts: 1

Quote:
Originally Posted by Yoshihiro
Hi all i give my answer to Mr-A XD . and that it's my old work from august but i think that can help you Mr-A for your downgrader Muhahahha.

Ok, so u wanna know what i know and where i am in this fucking project?
im gonna try to explain u a little bit but i can't give u all the informations
as some lamerz try to get WAB Brains as they dont have one...
I publish those informations as with them u can't do anything exvcept trying
to work on a Downgrader with more clues then now...

Well, for those who want to know if the WAB Downgrader works, just look at
our vidz on wab.com...
WE ARE NOT A FAKE TEAM WITH FAKEZ BRAINZ AND FAKEZ FILEZ !
Just look at what we have ALREADY done ... which team could say :
I've done more than WAB? ...

Everything is in this File :
X:/PSP/GAME/UPDATE/EBOOT.PBP

1st :
The EBOOT.PBP in the folder X:/PSP/GAME/UPDATE/ is detect by
the File : game_plugin.prx and is verifyed in the param.sfo
of the UPDATE_VER if it's superior of the one contain into
the PSP. If so, the File is launch.

2nd :
The EBOOT.PBP is launch, and the PSP extract the ELF encrypted
of the EBOOT and verify if it's validate by the loadexec.prx.

3rd :
Then, during the Black Screen, the PSP load another PRX :
update_plugin.prx which is the PSP OS Updater. So the ELF
of the EBOOT.PBP is a PRX and NOT an Exe file as many people
believe...

4th :
When it is launch, the PSP accept to uncompress the PSAR and
test the validation of each file he extract into the RAM 1 by 1.
If there is no error, then it check again the entire EBOOT.PBP
and extract one more time the ELF and look if it has been
modified. If everything is ok, then he accept the Update .

SO AS U COULD SEE, IT'S NOT THAT EASY TO MAKE A DOWNGRADER
AND SONY REALLY ROX BUT AS U KNOW, ALL COMPUTERS DATAS COULD
BE HACK AND ...

Just keep the faith into our cool Team. We've always done what
we said so just believe us, not the rumors or others lamerz... for all other i cant give anything more About all check sorry . way our downgrader and forget all fakes

..:::Yoshihiro::..


:::::::::::::::::::::::::::::::::::MR.A Reply ::::::::::::::::::::::::::::::


Why are you telling me things I already know? I know exactly how the upgrader gets loaded by the vsh, I know how the executable validation and decryption works, and I know how the upgrader works and how it decrypts and processes the PSAR file. As I explained in my article I didnt want to go into too much detail for the sake of the readers, just get to the point. Speaking of getting to the point - you seem to have completely missed it! Instead of actually properly responding to my article you just spout random bits of information which are not really even relevant in an attempt to make yourself look leet. It might work for some, but not me Why didnt you tell us how you plan to modify either the PRX or PSAR file and then re-encrypt so it will run on a 1.51+ PSP? Thats what you need to do but thats what you will NEVER manage to accomplish

Let me point a few things out for you, Yoshi. Without some sort of exploit a 1.51+ PSP will ONLY run properly signed and encrypted code. ONLY Sony can properly sign and encrypt data and you will never be able to do this. So I fail to see why you are so optimistic, since without being able to run unsigned code you will never have a working downgrader. Even if an exploit is found it will quickly be fixed so the battle really cannot be won until such time as a hardware mod appears.


Quote:
Originally Posted by Yoshihiro
Well, for those who want to know if the WAB Downgrader works, just look at
our vidz on wab.com...
WE ARE NOT A FAKE TEAM WITH FAKEZ BRAINZ AND FAKEZ FILEZ !

You've already admitted that you've never even had a working downgrader on 1.51+ so obviously those videos must be fake. Why would you release fake videos and string people along with your lies? Ah! I know! To collect more donations so you can buy more PSP's and other goodies. Nice.


Quote:
Originally Posted by Yoshihiro
Just look at what we have ALREADY done ... which team could say :
I've done more than WAB?


I really had to laugh when I read this. The size of your ego is fucking amazing. Lets see, what has WAB done for the "scene"? They've released a shitty launcher which required a UMD with the correct PRX modules to be inserted in order for games to work. In essence all this did was a "sceKernelLoadExec" call, not much else. Oh yeah, and some pointless firmware version changer. Wow, you guys rule! What about your V3 ISO loader? Oh, what about your DOWNGRADER?

Its funny to see what WAB thinks that they have done more than the guys at ps2dev.org - the real heroes who are responsible for the birth of PSP homebrew and all the open source libraries and code which WAB uses in their tools. Also lets not forget about the people behind the REAL ISO loaders who all bet WAB to it Open your eyes WAB, you guys havent done shit except cause drama, spread lies and rob poor unsuspecting people of their money.


Quote:
Originally Posted by Yoshihiro
Just keep the faith into our cool Team. We've always done what
we said so just believe us, not the rumors or others lamerz...

Ahem, always done what you said? Do I need to bring up the V3 ISO loader again?

The fact remains - a downgrader will NOT be possible the way WAB are trying to do it. They are going about it the wrong way. It might never be possible at all, for all we know.. its hard to say since so far nobody has been able to get a dump of the 2.0 kernel so we dont know if there are any exploits. The best and possibly only solution will be a hardware mod.. I for one am crossing my fingers that we will see something like this soon. One last thing - considering WAB didnt even have the skills to get an ISO loader working do you really think they will be able to achieve a working downgrader which is much more challenging? Seriously people, direct your hope elsewhere since you arent going to see anything from WAB.

Well props to Mr. A for setting the matter stright. WAB (We Are Bullsh*ter's), need to be called out on this. It would be nothing short of grand if WAB could prove themselvs. Thing is they can't!

If they have all what they need to Hax0r the 1.5x Firmware and there just "pollishing up" there Downgrader for 2.0 Users. Then why does everyone,who where told well before hand NOT TO UPDATE TO 2.0!! Have to continue to wait?

I've said it before and I'll say it again. "Let the 2.0 Useres eat Cake!!" Release the Damned Code for the 1.5x Users then go back and worry about those with 2.0.

Now it was noted that WAB also want to make a Firmware Downgrader that works with every PSP out there! (e.g. 100%), and the main hold up is that it could brick up to 200 out of 1000 PSP's!

So whats that like, 2:8 odds on bricking you PSP, or is more like a 8:2 chance that the Downgrader According to WAB! will work! Hell why oh why can't I get those kinds of Odds playing the Lotto or something!

There is no 100% with this kind of Hack and unfortunatly some Idiots will brick there PSP'S no matter what, Sh*t happens! But, if WAB has something to share besides there questionable Videos, then they need to spit it out!

Kudos to both of you
*bows*

Well, I'm going to get a wireless setup over weekend. If there is no downgrader by then, I'm updating to 2.0

You may get wireless setup witout 2.00

This sucks

But hey, it's still an amazing machine without 'downgraders' etc. !

Just one question though, is there anything of homebrew I cAN do ?? Like games, demo's etc. ?? That's made for 2.0 ?

Im pretty sure demos were going to be released in MS format sometime but who knows when.

And sorry to be anoying, but what's exactly the 'reason' why Homebrew Software 'engineers' can't write software for the PSP 2.0 ?

I mean, it's still a thing that can 'run' games, and games are software so ?

(yes I'm an idiot )

Well.. i don't wanna rub anyone's face in it... but MPH showed u


... didn't they?

if your referring to mr. A then no...he didnt say a downgrader was impossible. he said that going about it the way that WAB proposed wasnt going to happen. he even mentioned 'unless there is some sort of exploit' which is exactly what happened.

sorry if you were talking about something else.

Guess what! there is now a downgrader for psp 2.0 to 1.5 i used this last night and now my uk model 1003 psp is running on 1.5 go to http://WE TRY TO STEAL PSP-SPOT STAFF.WE TRY TO STEAL PSP-SPOT STAFF/ to find out more


at fist i was but i have been told this will work on all countries psp and is fully universal

once again i have no problem with my psp running 1.5 it now does home brew, im off to look for fastloader

HI GUY'S JUST WANTED TO LET YOU KNOW THAT I HAVE SUCCESSFULLY UPGRADED MY PSP-1004K V1.52 TO US V2.0 THEN DOWNGRADED TO JAP V1.50 THE SYSTEM WORKS GREAT AND I CAN NOW PLAY HOMEBREWS.

KUDOS TO MPH AND PROGRAMMERS WHO MADE THIS POSSIBLE.

THANKS