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Initial commit: FileRedirect dylib for iOS game modding
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‎.github/workflows/build.yml‎

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name: Build FileRedirect.dylib
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on:
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push:
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branches: [ main, master ]
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pull_request:
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branches: [ main, master ]
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# Allow manual trigger from the Actions tab
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workflow_dispatch:
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jobs:
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build:
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runs-on: macos-14 # Apple Silicon runner (has Xcode 15+)
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steps:
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- name: Checkout code
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uses: actions/checkout@v4
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- name: Show Xcode version
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run: xcodebuild -version
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- name: Show iOS SDK path
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run: xcrun --sdk iphoneos --show-sdk-path
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- name: Build dylib
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run: make
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working-directory: .
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- name: Verify output
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run: |
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ls -la FileRedirect.dylib
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file FileRedirect.dylib
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otool -l FileRedirect.dylib | head -40
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- name: Upload dylib artifact
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uses: actions/upload-artifact@v4
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with:
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name: FileRedirect-dylib
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path: FileRedirect.dylib
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retention-days: 90

‎Makefile‎

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# FileRedirectDylib Makefile
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#
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# Build a dylib for iOS arm64 using Xcode's clang.
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# Requires macOS with Xcode (or Xcode Command Line Tools) + iOS SDK.
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#
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# Usage:
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# make — build FileRedirect.dylib
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# make clean — remove build artifacts
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#
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# If your iOS SDK path differs, override it:
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# make SDK=/path/to/iPhoneOS.sdk
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# --- Configuration ---
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CC = xcrun -sdk iphoneos clang
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SDK ?= $(shell xcrun --sdk iphoneos --show-sdk-path)
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ARCH = arm64
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MIN_IOS = 12.0
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TARGET = FileRedirect.dylib
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SOURCES = tweak.m fishhook.c
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OBJECTS = tweak.o fishhook.o
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CFLAGS = -arch $(ARCH) \
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-isysroot $(SDK) \
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-miphoneos-version-min=$(MIN_IOS) \
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-fobjc-arc \
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-fmodules \
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-Wall
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LDFLAGS = -arch $(ARCH) \
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-isysroot $(SDK) \
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-miphoneos-version-min=$(MIN_IOS) \
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-dynamiclib \
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-framework Foundation \
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-install_name @executable_path/$(TARGET)
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# --- Targets ---
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all: $(TARGET)
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$(TARGET): $(OBJECTS)
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$(CC) $(LDFLAGS) -o $@ $^
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@echo "✅ Built $(TARGET) for iOS $(ARCH)"
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tweak.o: tweak.m fishhook.h
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$(CC) $(CFLAGS) -c tweak.m -o tweak.o
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fishhook.o: fishhook.c fishhook.h
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$(CC) $(CFLAGS) -c fishhook.c -o fishhook.o
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clean:
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rm -f $(OBJECTS) $(TARGET)
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@echo "🧹 Cleaned build artifacts"
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.PHONY: all clean

‎README.md‎

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# FileRedirectDylib
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A dylib for iOS that hooks file-access functions so games like **Bully** or **GTA San Andreas** transparently load modded files from `Documents/disk/` instead of the app bundle.
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## How It Works
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On non-jailbroken iOS the `.app` bundle is **read-only**. This dylib doesn't try to write into it. Instead it:
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1. Hooks C functions: `fopen`, `open`, `stat`, `access`
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2. Swizzles ObjC methods: `NSBundle -pathForResource:ofType:`, `NSFileManager -contentsAtPath:`
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3. When the game requests a file from its `.app` bundle, the hook checks if a replacement exists at `Documents/disk/<same relative path>`
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4. If yes → returns the modded file. If no → falls through to the original.
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## File Structure
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```
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FileRedirectDylib/
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├── .github/
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│ └── workflows/
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│ └── build.yml ← GitHub Actions CI (builds on free macOS runner)
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├── tweak.m ← Main hook/swizzle logic
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├── fishhook.h ← Facebook fishhook header
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├── fishhook.c ← Facebook fishhook implementation
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├── Makefile ← Build script
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└── README.md ← This file
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```
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## Building — No Mac Required (GitHub Actions)
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You do NOT need a Mac. GitHub gives you a free macOS build machine.
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### Step-by-step:
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1. **Create a GitHub account** if you don't have one: https://github.com
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2. **Create a new repository** (e.g. `FileRedirectDylib`)
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3. **Upload all files** from this folder to the repo, keeping the folder structure
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(make sure `.github/workflows/build.yml` is included)
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4. **Push / commit** — the build runs automatically
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5. Go to the **Actions** tab in your repo
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6. Click the latest workflow run → click **FileRedirect-dylib** under "Artifacts"
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7. **Download the zip** — it contains `FileRedirect.dylib` ready to inject
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You can also trigger a build manually: Actions tab → "Build FileRedirect.dylib" → "Run workflow".
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### Alternative: Build locally on macOS
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If you do have access to a Mac:
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```bash
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cd FileRedirectDylib
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make
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```
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This produces `FileRedirect.dylib` targeting iOS arm64 (min iOS 12.0).
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**Requirements:**
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- macOS with Xcode or Xcode Command Line Tools
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- iOS SDK (included with Xcode)
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## Injecting into an IPA
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### Option A: Using insert_dylib
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```bash
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# 1. Unzip the IPA
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mkdir payload && cd payload
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unzip ../GameName.ipa
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# 2. Copy dylib into the .app
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cp FileRedirect.dylib Payload/GameName.app/
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# 3. Inject the load command
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insert_dylib --strip-codesig --inplace \
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@executable_path/FileRedirect.dylib \
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Payload/GameName.app/GameName
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# 4. Re-zip as IPA
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zip -r ../GameName-modded.ipa Payload/
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```
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### Option B: Using optool
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```bash
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optool install -c load -p @executable_path/FileRedirect.dylib \
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-t Payload/GameName.app/GameName
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```
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## Re-signing & Sideloading
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After injection, the IPA needs to be re-signed:
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- **iOS App Signer** (macOS GUI) — easiest option
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- **ldid** — `ldid -S Payload/GameName.app/GameName`
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- **codesign** — `codesign -f -s "Apple Development: you@email.com" Payload/GameName.app`
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Then sideload with:
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- **AltStore** / **Sideloadly** / **TrollStore** (if available)
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## Using Mods
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1. Install the modded IPA on your device
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2. Open a file manager (e.g. Files app, or via iTunes File Sharing)
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3. Navigate to the app's `Documents/` folder
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4. Create a `disk/` subfolder if it doesn't exist (the dylib also auto-creates it)
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5. Place your modded files inside `disk/`, mirroring the `.app` bundle structure
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### Example for GTA SA
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If the original file is at:
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```
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GameName.app/texdb/gta3.txd
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```
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Place your modded version at:
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```
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Documents/disk/texdb/gta3.txd
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```
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The dylib will intercept the read and serve your file instead.
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## Debugging
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The dylib logs all redirected file accesses to the device console. View them with:
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```bash
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# Via Xcode → Window → Devices and Simulators → Open Console
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# Or via idevicesyslog:
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idevicesyslog | grep "FileRedirect"
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```
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Look for lines like:
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```
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[FileRedirect] fopen: /var/containers/.../MyApp.app/data/file.dat -> /var/containers/.../Documents/disk/data/file.dat
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```
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To disable logging in production, set `REDIRECT_LOG_ENABLED` to `0` in `tweak.m`.
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## Notes
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- This works on **non-jailbroken** iOS via sideloading
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- The `.app` bundle is never modified at runtime — all redirection is in-memory
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- If a file is NOT in `Documents/disk/`, the original bundle file is used (no breakage)
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- Compatible with **Bully**, **GTA San Andreas**, **GTA III**, **GTA Vice City**, **Max Payne**, and other Rockstar iOS ports

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