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Wario64
works for Gamestop (lol)
(08-28-2011, 06:46 PM)
Looks like X360 Slim models are finally hacked. I guess that new disc format is kinda pointless now, eh? At least now this opens up homebrew to pretty much anyone that feels like dwelving into it without having to find an old X360 model.

http://www.youtube.com/watch?v=JyYdL4L6vwE


Explanation of the hack that you'll probably won't understand:

**********************************
* The Xbox 360 reset glitch hack *
**********************************

Introduction / some important facts
===================================

tmbinc said it himself, software based approaches of running unsigned code on the 360 mostly don't work, it was designed to be secure from a software point of view.

The processor starts running code from ROM (1bl) , which then starts loading a RSA signed and RC4 crypted piece of code from NAND (CB).

CB then initialises the processor security engine, its task will be to do real time encryption and hash check of physical DRAM memory. From what we found, it's using AES128 for crypto and strong (Toeplitz ?) hashing. The crypto is different each boot because it is seeded at least from:
- A hash of the entire fuseset.
- The timebase counter value.
- A truly random value that comes from the hardware random number generator the processor embeds. on fats, that RNG could be electronically deactivated, but there's a check for "apparent randomness" (merely a count of 1 bits) in CB, it just waits for a seemingly proper random number.

CB can then run some kind of simple bytecode based software engine whose task will mainly be to initialise DRAM, CB can then load the next bootloader (CD) from NAND into it, and run it.

Basically, CD will load a base kernel from NAND, patch it and run it.

That kernel contains a small privileged piece of code (hypervisor), when the console runs, this is the only code that would have enough rights to run unsigned code.
In kernel versions 4532/4548, a critical flaw in it appeared, and all known 360 hacks needed to run one of those kernels and exploit that flaw to run unsigned code.
On current 360s, CD contains a hash of those 2 kernels and will stop the boot process if you try to load them.
The hypervisor is a relatively small piece of code to check for flaws and apparently no newer ones has any flaws that could allow running unsigned code.

On the other hand, tmbinc said the 360 wasn't designed to withstand certain hardware attacks such as the timing attack and "glitching".

Glitching here is basically the process of triggering processor bugs by electronical means.

This is the way we used to be able to run unsigned code.

The reset glitch in a few words
===============================

We found that by sending a tiny reset pulse to the processor while it is slowed down does not reset it but instead changes the way the code runs, it seems it's very efficient at making bootloaders memcmp functions always return "no differences". memcmp is often used to check the next bootloader SHA hash against a stored one, allowing it to run if they are the same. So we can put a bootloader that would fail hash check in NAND, glitch the previous one and that bootloader will run, allowing almost any code to run.

Details for the fat hack
========================

On fats, the bootloader we glitch is CB, so we can run the CD we want.

cjak found that by asserting the CPU_PLL_BYPASS signal, the CPU clock is slowed down a lot, there's a test point on the motherboard that's a fraction of CPU speed, it's 200Mhz when the dash runs, 66.6Mhz when the console boots, and 520Khz when that signal is asserted.

So it goes like that:
- We assert CPU_PLL_BYPASS around POST code 36 (hex).
- We wait for POST 39 start (POST 39 is the memcmp between stored hash and image hash), and start a counter.
- When that counter has reached a precise value (it's often around 62% of entire POST 39 length), we send a 100ns pulse on CPU_RESET.
- We wait some time and then we deassert CPU_PLL_BYPASS.
- The cpu speed goes back to normal, and with a bit of luck, instead of getting POST error AD, the boot process continues and CB runs our custom CD.

The NAND contains a zero-paired CB, our payload in a custom CD, and a modified SMC image.
A glitch being unreliable by nature, we use a modified SMC image that reboots infinitely (ie stock images reboot 5 times and then go RROD) until the console has booted properly.
In most cases, the glitch succeeds in less than 30 seconds from power on that way.

Details for the slim hack
=========================

The bootloader we glitch is CB_A, so we can run the CB_B we want.

On slims, we weren't able to find a motherboard track for CPU_PLL_BYPASS.
Our first idea was to remove the 27Mhz master 360 crystal and generate our own clock instead but it was a difficult modification and it didn't yield good results.
We then looked for other ways to slow the CPU clock down and found that the HANA chip had configurable PLL registers for the 100Mhz clock that feeds CPU and GPU differential pairs.
Apparently those registers are written by the SMC through an I2C bus.
I2C bus can be freely accessed, it's even available on a header (J2C3).
So the HANA chip will now become our weapon of choice to slow the CPU down (sorry tmbinc, you can't always be right, it isn't boring and it does sit on an interesting bus

So it goes like that:
- We send an i2c command to the HANA to slow down the CPU at POST code D8 .
- We wait for POST DA start (POST DA is the memcmp between stored hash and image hash), and start a counter.
- When that counter has reached a precise value, we send a 20ns pulse on CPU_RESET.
- We wait some time and then we send an i2c command to the HANA to restore regular CPU clock.
- The cpu speed goes back to normal, and with a bit of luck, instead of getting POST error F2, the boot process continues and CB_A runs our custom CB_B.

When CB_B starts, DRAM isn't initialised so we chose to only apply a few patches to it so that it can run any CD, the patches are:
- Always activate zero-paired mode, so that we can use a modified SMC image.
- Don't decrypt CD, instead expect a plaintext CD in NAND.
- Don't stop the boot process if CD hash isn't good.

CB_B is RC4 crypted, the key comes from the CPU key, so how do we patch CB_B without knowing the CPU key?
RC4 is basically:
crypted = plaintext xor pseudo-random-keystream
So if we know plaintext and crypted, we can get the keystream, and with the keystream, we can encrypt our own code. It goes like that:
guessed-pseudo-random-keystream = crypted xor plaintext
new-crypted = guessed-pseudo-random-keystream xor plaintext-patch
You could think there's a chicken and egg problem, how did we get plaintext in the first place?
Easy: we had plaintext CBs from fat consoles, and we thought the first few bytes of code would be the same as the new CB_B, so we could encrypt a tiny piece of code to dump the CPU key and decrypt CB_B!

The NAND contains CB_A, a patched CB_B, our payload in a custom plaintext CD, and a modified SMC image.
The SMC image is modified to have infinite reboot, and to prevent it from periodically sending I2C commands while we send ours.

Now, maybe you haven't realised yet, but CB_A contains no checks on revocation fuses, so it's an unpatchable hack !

Caveats
=======

Nothing is ever perfect, so there are a few caveats to that hack:
- Even in the glitch we found is pretty reliable (25% success rate per try on average), it can take up to a few minutes to boot to unsigned code.
- That success rate seems to depend on something like the hash of the modified bootloader we want to run (CD for fats and CB_B for slims).
- It requires precise and fast hardware to be able to send the reset pulse.

Our current implementation
==========================

We used a Xilinx CoolRunner II CPLD (xc2c64a) board, because it's fast, precise, updatable, cheap and can work with 2 different voltage levels at the same time.
We use the 48Mhz standby clock from the 360 for the glitch counter. For the slim hack, the counter even runs at 96Mhz (incremented on rising and falling edges of clock)
The cpld code is written in VHDL.
We need it to be aware of the current POST code, our first implementations used the whole 8 bits POST port for this, but we are now able to detect the changes of only 1 POST bit, making wiring easier.

Conclusion
==========

We tried not to include any MS copyrighted code in the released hack tools.
The purpose of this hack is to run Xell and other free software, I (GliGli) did NOT do it to promote piracy or anything related, I just want to be able to do whatever I want with the hardware I bought, including running my own native code on it.

Credits
=======

GliGli, Tiros: Reverse engineering and hack development.
cOz: Reverse engineering, beta testing.
Razkar, tuxuser: beta testing.
cjak, Redline99, SeventhSon, tmbinc, anyone I forgot... : Prior reverse engineering and/or hacking work on the 360.

Mr_Brit
Banned
(08-28-2011, 06:54 PM)
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If it's as difficult as JTAGing a fat 360 then it won't have the slightest effect on piracy, also JTAG systems are banned from Xbox live instantly unlike other 360s.
The_Monk
Member
(08-28-2011, 06:54 PM)
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Nobody can stop them. They will always find a way, I guess..
Seraphinianus
Banned
(08-28-2011, 06:56 PM)
But you see, I've invested so much into XBLA, so I am not tempted in the slightest.

because microsoft did a good job of investing in XBL, providing an incentive to not pirate, rather than featureless security firmware updates every day that treat you like a criminal.


and that's how it's done.
AbsoluteZero
Banned
(08-28-2011, 06:59 PM)
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Is the guy in that video intentionally talking like a pedophile?

Edit: Jesus christ, is he really demoing this thing by playing F-Zero X in the video? My Wii does that, no hacking required.

lol
entremet
Member
(08-28-2011, 06:59 PM)
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Cat and mouse game as always.
erpg
GAF parliamentarian
(08-28-2011, 07:01 PM)
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Why the fuck is this guy filming naked?

Wait, a thong?

God, why am I watching this. Cleanse my eyes.
angelfly
Member
(08-28-2011, 07:01 PM)
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Woot region-free 360 for me!
sixteen-bit
Member
(08-28-2011, 07:02 PM)
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Was a matter of time
amrod
Member
(08-28-2011, 07:02 PM)
Sooo...

Advantages of this Hack :

- All the 360 expect the Xenons will be compatible.
- It's unpatchable, in fact the CB is involved so early in the console boot process that it can't be revoked

Drawbacks:

- A chip is needed.
- The boot time varies and it can take up to a few minutes to run unsigned code.
- Even in the glitch we found is pretty reliable (25% success rate per try on average), it can take up to a few minutes to boot to unsigned code
Phonomezer
Banned
(08-28-2011, 07:02 PM)
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Just in time for the new dashboard, lol.
H_Prestige
Banned
(08-28-2011, 07:04 PM)
Why is this guy naked?
filipe
Member
(08-28-2011, 07:04 PM)
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Originally Posted by AbsoluteZero

Is the guy in that video intentionally talking like a pedophile?

Edit: Jesus christ, is he really demoing this thing by playing F-Zero X in the video? My Wii does that, no hacking required.

lol

Stupid edit is stupid. He's running an emulator, running a Nintendo product. On a 360.
Tagg9
(08-28-2011, 07:05 PM)
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So this is also compatible with FAT Xbox 360's? I have an old 360 with a non-working drive that I'd love to use as a media center. However, it was updated after the vulnerable dashboard.
Momo
Banned
(08-28-2011, 07:05 PM)
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Originally Posted by Lyphen

Why the fuck is this guy filming naked?

Wait, a thong?

God, why am I watching this. Cleanse my eyes.

sex sells.
ClovingWestbrook
Banned
(08-28-2011, 07:05 PM)
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This won't have any impact. Anything that requires opening the system up and crossing wires won't really make a dent. Wake me up when its as easy as the Wii, PS3, DS, or PSP.
Drkirby
Corporate Apologist
(08-28-2011, 07:06 PM)
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Was there ever any good homebrew for the system?

Was it possible to make it load games off the HDD without it needing the disc in it? Region bypass?

Originally Posted by filipe

Stupid edit is stupid. He's running an emulator, running a Nintendo product. On a 360.

I can do that on an Emulator on the Wii. Or my PC. Sure, its nice, but the 360 requires far more effort to mod then the other 2 choices listed.
AbsoluteZero
Banned
(08-28-2011, 07:06 PM)
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Originally Posted by filipe

Stupid edit is stupid. He's running an emulator, running a Nintendo product. On a 360.

Hacking your 360 and possibly bricking it, not to mention the large probability of getting banned from Xbox Live is not worth playing a N64 game that can be had for $10 on the Virtual Console and likely even less in actual cart form.

Try again.
Wario64
works for Gamestop (lol)
(08-28-2011, 07:07 PM)

Originally Posted by Drkirby

Was there ever any good homebrew for the system?

Was it possible to make it load games off the HDD without it needing the disc in it? Region bypass?

Well, there's emulation and XBMC...I'm not sure what else since I don't follow X360 homebrew.

And yes, you can load games off HDD (and even DLC/XBLA) without the disc (I think). That's pretty much the advantage of a JTAG.
angelfly
Member
(08-28-2011, 07:08 PM)
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Originally Posted by Drkirby

Was there ever any good homebrew for the system?

Was it possible to make it load games off the HDD without it needing the disc in it? Region bypass?


I can do that on a PSP. Or have an Emulator on the Wii. Or my PC. Sure, its nice, but the 360 requires far more effort to mod then the other 3 choices listed.

yes to both

edit: beaten
Raide
Member
(08-28-2011, 07:09 PM)
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Just in time for the new dash update, so they can start all their work again.
Funshine
Junior Member
(08-28-2011, 07:09 PM)
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Originally Posted by Lyphen

Why the fuck is this guy filming naked?

Wait, a thong?

God, why am I watching this. Cleanse my eyes.

to me it looked like he was nude in boots but idk
Drkirby
Corporate Apologist
(08-28-2011, 07:10 PM)
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But the 360 still has a max HDD size of 250GB, doesn't it?

Jtag was the one mod that never felt worth it. I had my Wii homebrewed so I can play imports with zero effort. I got a flash card so I could carry around all my DS games on one cart (Though in the end, I found I was fine with just one game at a time, so I never got a DSi compatible card). I modded my PS2 and PSP so I could have lower load times from my games.

At best, it does allow region bypass, but there aren't really any region locked imports that interest me, other then cave shmups that are more then I am willing to play.
Barkley's Justice
Member
(08-28-2011, 07:11 PM)
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good thing for us hackers have the worst taste in music.
Wario64
works for Gamestop (lol)
(08-28-2011, 07:11 PM)

Originally Posted by Drkirby

But the 360 still has a max HDD size of 250GB, doesn't it?

You can use an external HDD, and I think any size.
Barkley's Justice
Member
(08-28-2011, 07:12 PM)
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it also appears he walks by the tv completely nude at 1:10. cause, you know, thats how hackers do.
-MB-
Member
(08-28-2011, 07:12 PM)
-MB-'s Avatar

Originally Posted by Wario64

Well, there's emulation and XBMC...I'm not sure what else since I don't follow X360 homebrew.

And yes, you can load games off HDD (and even DLC/XBLA) without the disc (I think). That's pretty much the advantage of a JTAG.


I doubt there is xbmc, since there is 0 ppc support for it.
Unicorn
Member
(08-28-2011, 07:12 PM)
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Originally Posted by filipe

Stupid edit is stupid. He's running an emulator, running a Nintendo product. On a 360.

But OG xbox did this, 6 years ago.
Drkirby
Corporate Apologist
(08-28-2011, 07:13 PM)
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Originally Posted by Wario64

You can use an external HDD, and I think any size.

Alright. So it is something to think about if I get anther 360. But there are $500~ in things I would rather get first.

1) New Monitor
2) New CPU and Motherboard
Eiji
Member
(08-28-2011, 07:15 PM)
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Time to sell my fat JTAG 360 :D
MThanded
I Was There! Official L Receiver 2/12/2016
(08-28-2011, 07:16 PM)
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uh dude is naked in this video...
angelfly
Member
(08-28-2011, 07:16 PM)
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Originally Posted by Unicorn

But OG xbox did this, 6 years ago.

The point is that homebrew is running on a slim 360. sheesh
Parallax Scroll
best in Shadow of the Beast
(08-28-2011, 07:17 PM)
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Originally Posted by Wario64

And yes, you can load games off HDD (and even DLC/XBLA) without the disc (I think)

That sure would be nice, but I'm not gonna risk a console/account ban just so I don't have to switch discs.
Ramune
Member
(08-28-2011, 07:18 PM)
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What's the first thing you do when you hack a game console? Play a Nintendo game. Seems like an unwritten rule. Also really glad I'm not watching the video. ^_^;
angelfly
Member
(08-28-2011, 07:19 PM)
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Originally Posted by Parallax Scroll

That sure would be nice, but I'm not gonna risk a console/account ban just so I don't have to switch discs.

region-free is enough for me not to connect to XBL anymore
disappeared
Member
(08-28-2011, 07:19 PM)
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Going from modding the PS3 (ridiculously easy) to this... yeah, I think I'll just leave the little guy alone.
MThanded
I Was There! Official L Receiver 2/12/2016
(08-28-2011, 07:20 PM)
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Also this is a fairly complex hack. Interesting attack though.
Shadow of the BEAST
Banned
(08-28-2011, 07:23 PM)
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you think this will run ps2/wii/gc emulators in the future?
BKK
Member
(08-28-2011, 07:24 PM)

Originally Posted by angelfly

region-free is enough for me not to connect to XBL anymore

Sorry, I don't follow X360 scene too much, but does this mean I can buy a Euro X360 and play Japanese games? I have no interest in paying for XBL anyway, so will happily buy an offline region free X360.
filipe
Member
(08-28-2011, 07:25 PM)
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Originally Posted by AbsoluteZero

Hacking your 360 and possibly bricking it, not to mention the large probability of getting banned from Xbox Live is not worth playing a N64 game that can be had for $10 on the Virtual Console and likely even less in actual cart form.

Try again.

You do understand this is basically a proof of concept right? This is basically their "Hello World".

Try again.
AbsoluteZero
Banned
(08-28-2011, 07:27 PM)
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Originally Posted by filipe

You do understand this is basically a proof of concept right? This is basically their "Hello World".

Try again.

Do something that's going to impress me then. My PC did this back in 1999.

Edit: Just to keep it going:

Try again.
ClovingWestbrook
Banned
(08-28-2011, 07:29 PM)
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Originally Posted by Shadow of the BEAST

you think this will run ps2/wii/gc emulators in the future?

lol.
Zezboob
Member
(08-28-2011, 07:29 PM)
Brilliant.
Massa
Member
(08-28-2011, 07:30 PM)

Originally Posted by AbsoluteZero

Do something that's going to impress me then. My PC did this back in 1999.

Edit: Just to keep it going:

Try again.

I'm sure they'll post an update as soon as they have something to impress you, AbsoluteZero.
Eiji
Member
(08-28-2011, 07:30 PM)
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Hopefully the new matte 250GB Slims will be JTAG'able too.

http://www.eurogamer.net/articles/20...-be-matte-only
Neuromancer
The Mayuh of f'n Bawston
(08-28-2011, 07:41 PM)
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Major Nelson's going to get busted down to Captain for this.
onQ123
Junior Member
(08-28-2011, 07:46 PM)
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Sells are about to go through the roof ,

if they can make the homebrew as good as the 1st Xbox this will be nothing but Win
x-Lundz-x
Member
(08-28-2011, 07:47 PM)
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This really sounds like one if the stupidest things to that I have ever heard of.... Don't see the point.
Dragon
Banned
(08-28-2011, 07:50 PM)
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Originally Posted by AbsoluteZero

Do something that's going to impress me then. My PC did this back in 1999.

Edit: Just to keep it going:

Try again.

Yeah PCs did Wii graphics back in 1999 too. Zing.
Manp
(08-28-2011, 08:06 PM)
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i don't really care about moral arguments, i leave those to others... i'm only amazed by how smart these guys can be

:)

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