patch-porter

A simple .pchtxt porting tool.

Usage

1. Install Node.js, then install patch-porter using npm:

   npm install -g patch-porter

2. Port your pchtxt:

   patch-porter --from=mainA --to=mainB --input=A.pchtxt --output=B.pchtxt

   • --comment: Add ported address as comment to the output file
   • --arch=arm64: Set the processor architecture for the NSO file (arm/arm64/none), default: arm64

3. Done!

Tips

• Please keep @flag offset_shift ... in your pchtxt to help patch-porter finding the correct address

• If your pchtxt doesn't have @flag offset_shift 0x100, it means that the addresses in your pchtxt are not based on the NSO header offset.
  In this case, you need to decompress your NSO file using hactool, and disable NSO mode in patch-porter (--no-nso).

  hactool -t nso --uncompressed mainA.raw mainA
  hactool -t nso --uncompressed mainB.raw mainB
  patch-porter --from=mainA.raw --to=mainB.raw --input=A.pchtxt --output=B.pchtxt --no-nso

• After porting, search for [x] in new pchtxt to find errors

• patch-porter will automatically update assembly code for b and bl instructions, but some patches may still require manual updates

Use in Node.js

import { promises as fs } from 'fs'
import { portPchtxt } from 'patch-porter'

let fileA = await fs.readFile('mainA')
let fileB = await fs.readFile('mainB')
let pchtxtA = await fs.readFile('A.pchtxt', 'utf8')

let pchtxtB = await portPchtxt(fileA, fileB, pchtxtA)

await fs.writeFile('B.pchtxt', pchtxtB)

Credits

• disasm-web
• capstone
• keystone
• IPSwitch