SmokelessRuntimeEFIPatcher/README.md
2022-08-09 22:52:03 +02:00

6.6 KiB
Raw Blame History

SmokelessRuntimeEFIPatcher

These Are tool From "The Vault", that I decided to upload, so expect not fully polished product, or very slow Fixes if any

Discaimer

Use this at your own risk,I wont be responsible for any damage.

Also the code quality and the parsing engine are not that great, but were the best I could come to.

Question and Techinal discussion

You can try to reach me over https://discord.gg/Mj2Zc3jDFW

What is this

This is a simple tool to patch and Inject/Patch EFI modules at runtime, I developed this as I wasn't confortable with SPI flashing, as is not boring and require opening the laptop for every small change, as with AMD you can't flash from the OS a new BIOS, if is not signed...

Why this exist

The real reason why this exist, is that with an update Lenovo removed the Unlock BackDoor LenovoH2O-Unlocker, so after an update I couldn't change some adv option check Unlocking Lenovo H2O Bios I decided to develop a new way to do it....

How this work

When the EFI App is booted up, it look for a file Called SREP_Config.cfg, containing a list of command to execute, then will execute them

Support/Donate

If you want to donate/support please consider supportorting on Patreon

For one one donation, you can subribe for a month to Patreon then after the biilling, unsubsribe; (I might add a paypal in future)

How to use it

  • Download the Latest zip, from the Release Page

  • extract in a USB, such that exist a Folder Called EFI in the USB Root,

  • Create a SREP_Config.cfg and place in the root of the USB

  • boot from the USB

  • ??

  • Profit

SREP_Config Structure

The Config file can containg muliple batch of operation, the syntax is,

Op OpName1
    Argument 1
    Argument 2
    Argument n
Op OpName2
    Argument 1
    Argument 2
    Argument n
End

Op OpName3
    Argument 1
    Argument 2
    Argument n
End

Implemented Operiation

LoadFromFS

Load a EFI File in memory from a EFI partition, set as target

Arguments

* FileName : The Filename to load

LoadFromFV

Load a EFI File in memory from the FV(Firmware Volume)/The BIOS image, set as target

Arguments

* SectionName : The Section to load

Loaded

Target an already loaded Module

Arguments

* Name : The Name of the Loaded App to target

Patch

Patch the previus loaded target

Arguments

* Pattern : provide the Find and Replace a Patterns
* Offset : Provide and offset from the File start, and then the Byte to replace here
* RelNegOffset/RelPosOffset : negative/positive offset from previus Patch operation, and then the Byte to replace here

Exec

Execute the Previus loaded Module

To be Implemted

[ ] Uninstall Protocol
[ ] Lzma compressed object (very common on AMI BIOS)

Example

This is an Example of Loading a simple EFI, and executing it:

Op LoadFromFS APP.efi
Op Exec
End

This is an Example of Loading a simple EFI, replacing by pattern,and executing it

Find and replace AABBCCDDEEFF with AABBCCDDEEEE, find and replace AABBCCDDAABB with AABBCCDDAAAA:

Op LoadFromFS
APP.efi
Op Patch
Pattern
AABBCCDDEEFF
AABBCCDDEEEE
Op Patch
Pattern
AABBCCDDAABB
AABBCCDDAAAA
Op Exec
End

This is an Example of using relative pattern

Find the pattern AABBCCDDEEFF (replace with AABBCCDDEEFF, as we want it's own start address), then write AABBCCDDAAAA, at +50 from the pattern start

Op LoadFromFS
APP.efi
Op Patch
Pattern
AABBCCDDEEFF
AABBCCDDEEFF
Op Patch
RelPosOffset
50
AABBCCDDAAAA
Op Exec
End

Lenovo-BIOS-Unlock

Now a real example on how to use it to patch a Lenovo Legion Bios to Unlock the Advanced menu:

The Target H2O, is very simple in the regard on which form is shown...

in the H2OFormBrowserDxe there is a simple array of struct:

 struct Form
{
    GUID FormGUID;
    uint32_t isShown;
}

struct Form FormList[NO_OF_FORM];

The previus cE! backdoor, was very simple, looked like this:

if(gRS->GetVariable("cE!".....))
    for(int i=0;i<NO_OF_FORM;i++)
    {
        FormList[i].isShown=1;
    }

if the Variable didn't existed default isShow was used...

With this tool we can manually set the isShow Flag so we can replicate that behavoir...

The H2OFormBrowserDxe, is already loaded when we are able to execute SREP, so we can use the Loaded OP....

Let's say that we want to show the CBS Menu , it's guid is {B04535E3-3004-4946-9EB7-149428983053}, so it's hex representation is

E33545B0043046499EB7149428983053

given that is disabled, the complete Form Struct in memory will be

E33545B0043046499EB714942898305300000000

as we appended the 4 byte uint32_t of value 0;

we want to replace this with the 1, the little endian version of a uint32_t is

01 00 00 00

so the replace string is

 E33545B0043046499EB714942898305301000000

So putting all toghether the SREP_Config.cfg file look like

Op Loaded
H2OFormBrowserDxe
Op Patch
Pattern
E33545B0043046499EB714942898305300000000
E33545B0043046499EB714942898305301000000
Op End

Now we have patched the H2OFormBrowserDxe, but the Bios UI will be not loaded as we booted from a USB, but we can force it to load with

Op LoadFromFV
SetupUtilityApp
Op Exec

So the Finall SREP_Config.cfg is:

Op Loaded
H2OFormBrowserDxe
Op Patch
Pattern
E33545B0043046499EB714942898305300000000
E33545B0043046499EB714942898305301000000
Op End

Op LoadFromFV
SetupUtilityApp
Op Exec

Note You can't show the AOD menu with this, as it is not even loaded on non HX, cpu, you can force to load, Patching also AoDSetupDxe, but that's a topic for another day.

You could do the same to show the PBS menu and the Advanced Menu on intel one, if you are lazy you can use the combined one AMD/Intel provided here(I might have forgot to unlock something tbh):

Op Loaded
H2OFormBrowserDxe
Op Patch
Pattern
59B963B8C60E334099C18FD89F04022200000000
59B963B8C60E334099C18FD89F04022201000000
Op Patch
Pattern
E33545B0043046499EB714942898305300000000
E33545B0043046499EB714942898305301000000
Op Patch
Pattern
732871A65F92C64690B4A40F86A0917B00000000
732871A65F92C64690B4A40F86A0917B01000000
Op Patch
Pattern
9E76D4C6487F2A4D98E987ADCCF35CCC00000000
9E76D4C6487F2A4D98E987ADCCF35CCC01000000
Op End

Op LoadFromFV
SetupUtilityApp
Op Exec