gaasedelen / patching

An Interactive Binary Patching Plugin for IDA Pro

Patching - Interactive Binary Patching for IDA Pro

Overview

Patching assembly code to change the behavior of an existing program is not uncommon in malware analysis, software reverse engineering, and broader domains of security research. This project extends the popular IDA Pro disassembler to create a more robust interactive binary patching workflow designed for rapid iteration.

This project is currently powered by a minor fork of the ubiquitous Keystone Engine, supporting x86/x64 and Arm/Arm64 patching with plans to enable the remaining Keystone architectures in a future release.

Special thanks to Hex-Rays for supporting the development of this plugin.

Releases

• v0.1 -- Initial release

Installation

This plugin requires IDA 7.6 and Python 3. It supports Windows, Linux, and macOS.

Easy Install

Run the following line in the IDA console to automatically install the plugin:

Windows / Linux

import urllib.request as r; exec(r.urlopen('https://github.com/gaasedelen/patching/raw/main/install.py').read())

macOS

import urllib.request as r; exec(r.urlopen('https://github.com/gaasedelen/patching/raw/main/install.py', cafile='/etc/ssl/cert.pem').read())

Manual Install

Alternatively, the plugin can be manually installed by downloading the distributable plugin package for your respective platform from the releases page and unzipping it to your plugins folder.

It is strongly recommended you install this plugin into IDA's user plugin directory:

import ida_diskio, os; print(os.path.join(ida_diskio.get_user_idadir(), "plugins"))

Usage

The patching plugin will automatically load for supported architectures (x86/x64/Arm/Arm64) and inject relevant patching actions into the right click context menu of the IDA disassembly views:

A complete listing of the contextual patching actions are described in the following sections.

Assemble

The main patching dialog can be launched via the Assemble action in the right click context menu. It simulates a basic IDA disassembly view that can be used to edit one or several instructions in rapid succession.

The assembly line is an editable field that can be used to modify instructions in real-time. Pressing enter will commit (patch) the entered instruction into the database.

Your current location (a.k.a your cursor) will always be highlighted in green. Instructions that will be clobbered as a result of your patch / edit will be highlighted in red prior to committing the patch.

Finally, the UP and DOWN arrow keys can be used while still focused on the editable assembly text field to quickly move the cursor up and down the disassembly view without using the mouse.

NOP

The most common patching action is to NOP out one or more instructions. For this reason, the NOP action will always be visible in the right click menu for quick access.

Individual instructions can be NOP'ed, as well as a selected range of instructions.

Force Conditional Jump

Forcing a conditional jump to always execute a 'good' path is another common patching action. The plugin will only show this action when right clicking a conditional jump instruction.

If you never want a conditional jump to be taken, you can just NOP it instead!

Save & Quick Apply

Patches can be saved (applied) to a selected executable via the patching submenu at any time. The quick-apply action makes it even faster to save subsequent patches using the same settings.

The plugin will also make an active effort to retain a backup (.bak) of the original executable which it uses to 'cleanly' apply the current set of database patches during each save.

Revert Patch

Finally, if you are ever unhappy with a patch you can simply right click patched (yellow) blocks of instructions to revert them to their original value.

While it is 'easy' to revert bytes back to their original value, it can be 'hard' to restore analysis to its previous state. Reverting a patch may occasionally require additional human fixups.

Known Bugs

• Further improve ARM / ARM64 / THUMB correctness
• Define 'better' behavior for cpp::like::symbols(...) / IDBs (very sketchy right now)
• Adding / Updating / Modifying / Showing / Warning about Relocation Entries??
• Handle renamed registers (like against dwarf annotated idb)?
• A number of new instructions (circa 2017 and later) are not supported by Keystone
• A few problematic instruction encodings by Keystone

Future Work

Time and motivation permitting, future work may include:

• Enable the remaining major architectures supported by Keystone:
  • PPC32 / PPC64 / MIPS32 / MIPS64 / SPARC / SystemZ
• Multi instruction assembly (eg. xor eax, eax; ret;)
• Multi line assembly (eg. shellcode / asm labels)
• Interactive byte / data / string editing
• Symbol hinting / auto-complete / fuzzy-matching
• Syntax highlighting the editable assembly line
• Better hinting of errors, syntax issues, etc
• NOP / Force Jump from Hex-Rays view (sounds easy, but probably pretty hard!)
• radio button toggle between 'pretty print' mode vs 'raw' mode? or display both?

  Pretty:  mov     [rsp+48h+dwCreationDisposition], 3
     Raw:  mov     [rsp+20h], 3
  

I welcome external contributions, issues, and feature requests. Please make any pull requests to the develop branch of this repository if you would like them to be considered for a future release.

Authors

• Markus Gaasedelen (@gaasedelen)

patching's Issues

problem with assemble

when i try to use assemble i get error

i try on ida 7.6 and 7.7 and get some error
OC-widows10
executable file-arm64 dylib
if you need i can give .dmp file

[Feature request] In-memory patching

First of all, commendations on your great work ! The built-in assembler for IDA was pretty much unusable so the patching had to be done with an external program, making the whole process really tedious (load file in IDA -> debug -> patch in another app -> reload file in IDA -> reanalyze the whole thing -> debug -> rinse and repeat). This finally lets me drop the external app from the workflow and no reloading required, simply awesome !

As far as binary patching goes, it currently works as-is. Finally also the "patched bytes" section actually works since your plugin keeps the backup file, and IDA does not get confused anymore on what is actually patched and what is original.

I have a request though which would make it even better, incorporate the in-memory patching option from (currently defunct and unmaintained, unfortunately) https://github.com/scottmudge/DebugAutoPatch . The "About" section outlines well some of the grievances with the IDA built-in patching system and fixes them. I do not know how non-trivial it would be to add those features to this patcher plugin though

'%' can make IDA crash

env

python 3.9.9
IDA: 7.6

IDA Pro crashes when I type the '%' character in the Assemble window

OSError: [Errno 22] Invalid argument when trying to patch a large chunk

When I tried to patch a large chunk, the patch will fail with OSError: [Errno 22] Invalid argument from https://github.com/gaasedelen/patching/blob/main/plugins/patching/util/ida.py#L101
I am trying to set a range of data to 0

crush in ida pro 7.7

when click this

ida will crush

not working

Traceback (most recent call last):
File "C:\Users/user/AppData/Roaming/Hex-Rays/IDA Pro/plugins\patching\actions.py", line 127, in activate
wid = PatchingController(self.core, get_current_ea(ctx))
File "C:\Users/user/AppData/Roaming/Hex-Rays/IDA Pro/plugins\patching\ui\preview.py", line 47, in init
self.refresh()
File "C:\Users/user/AppData/Roaming/Hex-Rays/IDA Pro/plugins\patching\ui\preview.py", line 223, in refresh
self.select_address(self.address)
File "C:\Users/user/AppData/Roaming/Hex-Rays/IDA Pro/plugins\patching\ui\preview.py", line 68, in select_address
if insn.address != ea:
AttributeError: 'NoneType' object has no attribute 'address'

Can't install the plugin

I tried the easy install command and it gives me the error of "ModuleNotFoundError: No module named '_socket'", so i tried manually installing it by dragging and dropping the patching folder directly inside the ida pro plugins folder along with "patching.py", then i used the manual install command listed in the instructions to install this plugin, next i restarted ida pro to check it out but still doesnt show up when i righ click a function. I have the latest python version which i downloaded straight from the oficial website, i even upgraded the pip, setuptool, six and wheel just in case as i don't have any ideia what is needed or not but still nothing, tried it in both ida pro 7.6 and 7.7.

I am on windows 11 with latest updates, let me know if you need any more info, thanks.

Nice plugin! Please improve the minor details

I want to say this one is so much better than the keypatch plugin.

Can you enlarge the dialog or perhaps calculate the proper width? I'm trying to avoid the horizontal scroll bar, so as long as the calculated width is not bigger than the screen width, I think it will be fine.

Assemble not working in windows 10

Patching cancelled...

Patching cancelled... when try to apply

error when click "Apply patches to..."

---------------------------------------------------------------------------------------------
Traceback (most recent call last):
  File "C:\Users/Cirn09/AppData/Roaming/Hex-Rays/IDA Pro/plugins\patching\actions.py", line 148, in activate
    controller = SaveController(self.core)
  File "C:\Users/Cirn09/AppData/Roaming/Hex-Rays/IDA Pro/plugins\patching\ui\save.py", line 30, in __init__
    self.view = SaveDialog(self)
  File "C:\Users/Cirn09/AppData/Roaming/Hex-Rays/IDA Pro/plugins\patching\ui\save_ui.py", line 13, in __init__
    self._ui_init()
  File "C:\Users/Cirn09/AppData/Roaming/Hex-Rays/IDA Pro/plugins\patching\ui\save_ui.py", line 30, in _ui_init
    self.setWindowFlags(self.windowFlags() & remove_flags)
TypeError: unsupported operand type(s) for &: 'WindowFlags' and 'WindowFlags'
Traceback (most recent call last):
  File "C:\Users/Cirn09/AppData/Roaming/Hex-Rays/IDA Pro/plugins\patching\actions.py", line 148, in activate
    controller = SaveController(self.core)
  File "C:\Users/Cirn09/AppData/Roaming/Hex-Rays/IDA Pro/plugins\patching\ui\save.py", line 30, in __init__
    self.view = SaveDialog(self)
  File "C:\Users/Cirn09/AppData/Roaming/Hex-Rays/IDA Pro/plugins\patching\ui\save_ui.py", line 13, in __init__
    self._ui_init()
  File "C:\Users/Cirn09/AppData/Roaming/Hex-Rays/IDA Pro/plugins\patching\ui\save_ui.py", line 30, in _ui_init
    self.setWindowFlags(self.windowFlags() & remove_flags)
TypeError: unsupported operand type(s) for &: 'WindowFlags' and 'WindowFlags'

https://github.com/gaasedelen/patching/blob/main/plugins/patching/ui/save_ui.py#L30

>>> print(self.windowFlags())
<PyQt5.QtCore.Qt.WindowFlags object at 0x000002048BED15B0>
>>> print(remove_flags)
<PyQt5.QtCore.Qt.WindowFlags object at 0x000002048BF7EAB0>

versions info:

• Windows 10
• Python 3.10
• PyQt5 5.15.6
• patching: last release
• Ida 7.6

Revert one patch at a time

The Revert action reverts everything I've edited, can you change this behavior?
It would be better to revert only the selected address range.

need to delete patching.py in plugins dir

Python>import urllib.request as r; exec(r.urlopen('https://github.com/gaasedelen/patching/raw/main/install.py').read())
[] Starting auto installer for 'Patching' plugin...
[] Fetching info from GitHub...
[] Downloading patching_win32.zip...
[] Saving patching_win32.zip to disk...
[] Removing existing plugin...
[] Unzipping patching_win32.zip...
[+] Patching v0.1.2 installed successfully!
[!] Restart IDA to use the updated plugin
install successfully

Then i restart ida,
C:\Users\asdf\AppData\Roaming\Hex-Rays\IDA Pro\plugins\patching.py: No module named 'patching.util'; 'patching' is not a package
Traceback (most recent call last):
File "E:\IDA Pro 7.6\python\3\ida_idaapi.py", line 617, in IDAPython_ExecScript
exec(code, g)
File "C:/Users/asdf/AppData/Roaming/Hex-Rays/IDA Pro/plugins/patching.py", line 42, in
import patching
File "E:\IDA Pro 7.6\plugins\patching.py", line 43, in
from patching.util.python import reload_package
ModuleNotFoundError: No module named 'patching.util'; 'patching' is not a package

Then i try to delete \IDA Pro 7.6\plugins\patching.py, reserve \Users\asdf\AppData\Roaming\Hex-Rays\IDA Pro\plugins\patching.py,
thats works.

Thanks for a great plugin

Great job, what an useful plugin.

this is not really a bug but rather a question, i tried open a request with no sucess.

There is any way to assemble jmp +5 style short jumps for example.

Thanks for your incredible job.

Ricardo

Jump to next line on enter key

In the Assemble dialog, the cursor should jump to the next line when I press the Enter key.
This is a required feature to edit/write multiple assembly code.

Can you add this behavior?

Whether to support script calls to modify the assembly

I want to develop another IDA plugins and call pathcing api in other plugins to modify the assembly code, does patching support this operation?

idasm is A Python Assembler Script Tool for IDA Pro based on "patching"

Dear gaasedelen,
I extract core codes from your ingenious "patching" plugin. Now we can use "patching" as an automatic patching work engine for IDA. Here is the repository link: https://github.com/lyciumlee/idasm .