Upgrading to 2.5 without losing ability to downgrade.

[AzureBlack]

I was thinking of was to do such, and I though that maybe, you could could actually patch the end of an update file (2.5 update) with a file telling the PSP its really 1.0. Therefore, you could still run the 1.5 update and go back. update and go back...Im not sure if this is possible, seeing as im not a coder, but its just a thought. Its kind of a preventative measure, and couldnt be used to downgrade already 2.5 psps, but if successful, could be used for future updates.

[Train]

to tell the psp it has to have a way to execute unsigned files(hack, expliot, you may call it) but until we find an expliot in 2.5 there will be no way to downgrade it

[gracz54]

this is a good idea, but we dont actually know how to haxor the ipl of the psp... whatever it would be, but it has the version number

[Slasher]

Originally Posted by albut35

to tell the psp it has to have a way to execute unsigned files(hack, expliot, you may call it) but until we find an expliot in 2.5 there will be no way to downgrade it

read again, he's saying that if we modify the update to add a thing that makes your psp think its a 1.00 in the eboot, so then you have 2.5, but it thinks its a 1.0 so you could upgrade(downgrade) to 1.5

[Dibblah]

Originally Posted by Slasher

read again, he's saying that if we modify the update to add a thing that makes your psp think its a 1.00 in the eboot, so then you have 2.5, but it thinks its a 1.0 so you could upgrade(downgrade) to 1.5

If you modify the update in any way, it's no longer signed.

[TeamOverload]

yup, it will boot to the update screen, and then just say that the update is corrupt

[st.jimmy]

this is just impossible cuz we cant modify the eboot unless we get the source from sony. VERY unlikely, right there.

[scrubs]

mph is ****in d umb for releasing the exploit on 2.0
if they woulda kept silent and waited till 2.5, maybe the xploit would still be there
but nooooooooooooooooooooo lets brag!

[TeamOverload]

dont flame mph, and 2.5 mite not be out if it wasnt for the exploit. i think they released 2.5 to try and get more people to update instead of use homebrew.

[AzureBlack]

Originally Posted by TeamOverload

dont flame mph, and 2.5 mite not be out if it wasnt for the exploit. i think they released 2.5 to try and get more people to update instead of use homebrew.

Exactly. If MPH kept their mouth shut, 2.5 wouldnt exist, and there wouldnt be a need for another exploit, that and the fact that most people would still be stuck at 2.0 (including myself). There are other thoughts I was having about an exploit...when the PSP is updating and writing over files, does it read the files first? if that were true, we could possible modify one of the files in the PSP (one of the PRXs or something of that sort) so that when we write over it, the PSP reads it, and can be exploited from there...Once again. Im not a coder, so im not aware if this is able to happen or not.

[AzureBlack]

Are there any left over files that an update leaves in the PSP once its done updating? Or files that become useless after updating?

[relkai]

A 2.50 PSP which THINKS it's a 1.00 would be completely useless for future games that require the 2.50 firmware. Ok, we would have the right encryption keys to run the game but if it checks the version of your fooled PSP, you're stuck.

[Darkhaste]

All these things have been considered ever since 1.51 firmware came out. They have been tried and it doesn't work. If anything is changed in the update eboot.pbp the psp will see the file as corrupt as it's no longer signed. When sony sign an eboot it is signed with a cypher that uses the whole file. If so much as one byte changes the encryption will change and the PSP will register it as corrupt.

We can't decrypt the eboots anyway so what's the point?

Also swapping memory sticks with another update eboot does not work either.

[iball®]

Eventually, probably a year from now, SOMEONE will get ahold of the proper software and will have the correct knowledge to create a custom firmware that just flat-out allows ANY CODE, unsigned or not, to be run from ANYTHING (UMD or MS). That's the MAIN problem, period. Sony has all this encryption in place to STOP the running of unsigned code.
Now, about those Yarouze systems....hmmm...could this be Sony's way of saying "sorry" to homebrewers and "fsck you" to pirates? We don't know.
Someone in Japan might just take a PSP "Yarouze" system and code a new eboot loader for 2.5 with it. Of course, their digital "fingerprints" would be all over the signing of that code, but it could happen.

[AzureBlack]

Originally Posted by Darkhaste

All these things have been considered ever since 1.51 firmware came out. They have been tried and it doesn't work. If anything is changed in the update eboot.pbp the psp will see the file as corrupt as it's no longer signed. When sony sign an eboot it is signed with a cypher that uses the whole file. If so much as one byte changes the encryption will change and the PSP will register it as corrupt.

We can't decrypt the eboots anyway so what's the point?

Also swapping memory sticks with another update eboot does not work either.

Dude, llok at my join date, look at my post count, do you THINK im not aware of whats been thought of? I havent heard anyone post what I just said, so please don't try to act like im the novice here k?

[Ha! Ijustfoundmygenesis!]

O my God!

I've been gone so long there has been how many new firmware updates since september? 4 maybe? Sry bout that pretty much unrelated.


Anyways, like 2.0 when it first came out, u will have to wait till a exploit comes out that changes game files to make it compatable. I still think its amazing they got ver 2.0 to run games.


edit: stupid thats not what the guys saying............: Argh:

[Hunterhood2001]

Originally Posted by AzureBlack

Dude, llok at my join date, look at my post count, do you THINK im not aware of whats been thought of? I havent heard anyone post what I just said, so please don't try to act like im the novice here k?

You are thinking of INJECTING some code, while the psp updates itself? My 2cents: the PSP is not checking any file AFTER the check of integrity and firmware ... Therefore it will not allow something to be injected.

And after these posting SONY will be aware of your idea So firmware 3.0 will close the rest of the holes and we are stuck.

I'm fine with that, as i buy the games i play, but i would likt to have the possibility of homebrew on >2.0 firmware ... SONY??? Do you hear me

[NeilR]

Originally Posted by Hunterhood2001

but i would likt to have the possibility of homebrew on >2.0 firmware ... SONY??? Do you hear me

It already can... we have a whole forum section dedicated to 2.0 homebrew.

[AzureBlack]

Originally Posted by Hunterhood2001

You are thinking of INJECTING some code, while the psp updates itself? My 2cents: the PSP is not checking any file AFTER the check of integrity and firmware ... Therefore it will not allow something to be injected.

And after these posting SONY will be aware of your idea So firmware 3.0 will close the rest of the holes and we are stuck.

I'm fine with that, as i buy the games i play, but i would likt to have the possibility of homebrew on >2.0 firmware ... SONY??? Do you hear me

nope, not 3.0 yet, im sure 2.51 and 2.52 wwill come out, boasting "new" features of the PSP system to try and lure more people into upgrading when it really doesnt give you any features you didnt already have.

[tru89x]

you know in all honesty there is no reason for anyone to update to 2.5 because the only reason to would be if you could use that location free player.

[AzureBlack]

Originally Posted by tru89x

you know in all honesty there is no reason for anyone to update to 2.5 because the only reason to would be if you could use that location free player.

We realize that already, but some people get suckered in, that, and eventually v2.5 firmware will be required to run games.

[Mast3r_Shak3]

Yeah, the only good thing sony could put in to make someone want to upgrade is probably flash and quicktime support