mobile-security

# Mobile Game Security ## Overview This skill covers mobile security resources from the awesome-game-security collection, focusing on Android and iOS game security research, reverse engineering, and protection bypass techniques. ## README Coverage - `Cheat > Magisk` - `Cheat > Xposed` - `Cheat > Frida` - `Cheat > Hook ART(android)` - `Cheat > Hook syscall(android)` - `Cheat > Android Terminal Emulator` - `Cheat > Android File Explorer` - `Cheat > Android Memory Explorer` - `Cheat > Android Application CVE` - `Cheat > Android Kernel CVE` - `Cheat > Android Bootloader Bypass` - `Cheat > IoT / Smart devices` - `Cheat > Android ROM` - `Cheat > Android Device Trees` - `Cheat > Android Kernel Source` - `Cheat > Android Root` - `Cheat > Android Kernel driver development` - `Cheat > Android Kernel Explorer` - `Cheat > Android Kernel Driver` - `Cheat > Android Network Explorer` - `Cheat > Android memory loading` - `Cheat > IOS jailbreak` - `Cheat > IOS Memory Explorer` - `Cheat > IOS File Explorer` - `Cheat > IOS App Packaging` - `Cheat > Injection:Android` - `Cheat > Injection:IOS` - `Anti Cheat > Detection:Android root` - `Anti Cheat > Detection:Magisk` - `Anti Cheat > Detection:Frida` - `Some Tricks > Android` - `Android Emulator` - `IOS Emulator` ## Android Security ### APK Analysis #### Tools - **apktool**: Decompile/recompile APKs - **jadx**: DEX to Java decompiler - **APKiD**: Identify packers/protectors - **Frida**: Dynamic instrumentation - **APKLab**: VS Code integration #### Workflow ```bash # Decompile APK apktool d game.apk # Analyze DEX files jadx -d output game.apk # Identify protection apkid game.apk ``` ### Native Library Analysis #### IL2CPP Games (Unity) ``` 1. Extract libil2cpp.so from APK 2. Use IL2CPP Dumper to generate headers 3. Analyze with IDA/Ghidra 4. Hook using Frida or native hooks ``` #### Native Games ``` 1. Identify target libraries (.so files) 2. Analyze with reverse engineering tools 3. Pattern scan for functions 4. Apply hooks/patches ``` ### Memory Manipulation #### Tools - **GameGuardian**: Memory editor - **Cheat Engine (ceserver)**: Remote debugging - **Custom memory tools**: Direct /proc/pid/mem access #### Access Methods ```c // Via /proc filesystem int fd = open("/proc/pid/mem", O_RDWR); pread64(fd, buffer, size, address); pwrite64(fd, buffer, size, address); ``` ### Hooking Frameworks #### Frida ```javascript // Basic function hook Interceptor.attach(Module.findExportByName("libgame.so", "function_name"), { onEnter: function(args) { console.log("Called with: " + args[0]); }, onLeave: function(retval) { retval.replace(0); } }); ``` #### Native Hooks - **Substrate**: Inline hooking framework - **And64InlineHook**: ARM64 inline hooks - **xHook**: PLT hook library - **Dobby**: Multi-platform hook framework ### Modern Root Solutions #### KernelSU ``` - Kernel-based root solution, works at kernel level (no /system modification) - Module system compatible with Magisk modules via KSU module API - Stealth advantage: no su binary on filesystem, harder to detect - Requires custom kernel or GKI (Generic Kernel Image) patching - APatch: newer alternative, patches boot.img with KernelPatch ``` #### APatch ``` - Patches Android kernel at boot via KernelPatch - No need for custom kernel source (works on stock GKI kernels) - Module support similar to Magisk/KernelSU - Root process runs within kernel context ``` #### Root Solution Comparison ``` | Solution | Level | Stealth | GKI Support | Module System | |-----------|-------------|---------|-------------|---------------| | Magisk | User/Init | Medium | Yes | Mature | | KernelSU | Kernel | High | Yes | Growing | | APatch | Kernel | High | Yes | Growing | ``` ### Managed Dynamic Instrumentation on Rooted Android ``` Methodology (KSU/Magisk module + single binary engine): - Package injector + loader + agent into one ARM64 binary to reduce footprint and version mismatch risk - Expose a local HTTP RPC control plane (127.0.0.1:<port>) for low-latency script management, session listing, and function calls - Keep boot path safe: do NOT start instrumentation engine in post-fs-data/service early stage; use delayed manual start after boot_completed to avoid zygote/module startup contention Injection modes: - Attach: ptrace into running process, inject bootstrap shellcode, resolve libc symbols, dlopen agent, then run JS - Spawn: zygote-hijack path to pause child at fork and inject before app initialization (covers Application.onCreate / class init) - Watch-SO: eBPF-based dlopen monitor that triggers injection when target native library is loaded Stealth tiers: - NORMAL: direct RWX patching (fastest, easiest to detect) - WXSHADOW: shadow-page patching to reduce /proc memory visibility - RECOMP: function recompile/relocation with minimal inline patch Operational pattern: - Lifecycle commands: start/stop/restart/status - Analysis mode: temporarily disable conflicting zygisk modules, reboot, instrument, then restore and reboot back to normal mode - Troubleshooting-first logging: keep manager and engine logs separate ``` ### Root Detection Bypass #### Common Checks ``` - /system/bin/su existence - /system/xbin/su existence - Build.TAGS contains "test-keys" - ro.build.selinux property - Magisk files/folders - Package manager checks ``` #### Bypass Methods - **Magisk DenyList / Shamiko**: Modern root hiding (replaces MagiskHide) - **LSPosed/EdXposed**: Xposed framework hooks - **Frida scripts**: Hook detection functions - **APK patching**: Remove detection code - **KernelSU SU isolation**: Process-level root visibility control ### Zygisk Modules ```cpp // Zygisk module structure class Module : public zygisk::ModuleBase { void onLoad(zygisk::Api *api, JNIEnv *env) override { this->api = api; this->env = env; } void preAppSpecialize(zygisk::AppSpecializeArgs *args) override { // Before app loads } void postAppSpecialize(const zygisk::AppSpecializeArgs *args) override { // After app loads - inject here } }; ``` ### Android Protections #### Common Protectors - **Tencent ACE**: Chinese market protection - **AppSealing**: Commercial protection - **DexGuard/ProGuard**: Obfuscation - **Arxan**: Enterprise protection ## iOS Security ### Analysis Tools - **Hopper**: Disassembler - **IDA Pro**: Industry standard - **class-dump**: Objective-C header extraction - **Frida**: Dynamic instrumentation - **Clutch/dumpdecrypted**: App decryption ### Jailbreak Tools - **H5GG**: iOS cheat engine - **Flex**: Runtime patching - **Cycript**: Runtime manipulation - **ceserver-ios**: Cheat Engine for iOS ### Hooking (Jailbroken) ```objc // Using Logos (Theos) %hook TargetClass - (int)targetMethod:(int)arg { int result = %orig; return result * 2; // Modify return } %end ``` ### Non-Jailbreak Techniques - **Sideloading**: Modified IPAs - **Enterprise certificates**: Custom signing - **AltStore**: Self-signing tool ## Unity Mobile Games ### IL2CPP Analysis ``` 1. Locate libil2cpp.so (Android) or UnityFramework (iOS) 2. Find global-metadata.dat 3. Run IL2CPPDumper 4. Generate SDK/headers 5. Hook target functions ``` ### Mono Analysis ``` 1. Extract managed DLLs 2. Decompile with dnSpy/ILSpy 3. Modify and repackage 4. Or hook at runtime ``` ### Common Targets ``` - Currency/coins values - Player stats (health, damage) - Inventory manipulation - Premium unlocks - Ad removal ``` ## Unreal Mobile Games ### Analysis Approach ``` 1. Identify UE version 2. Dump SDK using appropriate tool 3. Locate GObjects, GNames 4. Find target functionality 5. Apply memory patches or hooks ``` ## Overlay Rendering (Android) ### Surface-Based ```cpp // Native surface overlay ANativeWindow* window = ANativeWindow_fromSurface(env, surface); // Render using OpenGL ES or Vulkan ``` ### ImGui Integration - Zygisk + ImGui modules - Surface hijacking - Direct framebuffer access ## Network Analysis ### Tools - **mitmproxy**: MITM proxy - **Charles Proxy**: Traffic analysis - **Frida SSL bypass**: Certificate pinning bypass ### Certificate Pinning Bypass ```javascript // Frida universal SSL bypass Java.perform(function() { var TrustManager = Java.registerClass({ implements: [X509TrustManager], methods: { checkClientTrusted: function() {}, checkServerTrusted: function() {}, getAcceptedIssuers: function() { return []; } } }); // Install custom TrustManager }); ``` ## Anti-Cheat on Mobile ### Common Systems - **Tencent ACE**: Chinese games - **NetEase Protection**: NetEase games - **Custom solutions**: Per-game implementations ### Detection Methods ``` - Root/jailbreak detection - Frida detection - Emulator detection - Integrity checks - Debugger detection - Hook detection ``` ### Bypass Strategies ``` 1. Static analysis of detection code 2. Hook detection functions 3. Hide injection footprint 4. Timing attack consideration 5. Clean environment emulation ``` ## eBPF-Based Tools ### Tracing & Hooking ``` - stackplz: eBPF-based stack trace tool for Android - eDBG: eBPF-powered debugger for Android processes - tracee: Aqua Security's eBPF runtime security tool (Linux/Android) - eBPF hooking: attach to tracepoints, kprobes, uprobes without kernel module ``` ### Advantages Over Traditional Approaches ``` - No kernel module compilation required (runs in eBPF VM) - Works on stock GKI kernels with BTF support - Lower detection surface than kernel driver injection - CO-RE (Compile Once, Run Everywhere) portability - Safe: eBPF verifier prevents kernel crashes ``` ## Android Kernel Driver Development ### Development Patterns ``` - Loadable kernel module (LKM) for older kernels - GKI-compatible modules via vendor_dlkm partition - Kernel build scripts: build from AOSP source or vendor BSP - Device Trees: hardware description for board-specific drivers ``` ### Common Use Cases in Game Security ``` - Process memory access: /dev/custom_mem → read/write target process - Syscall hooking: __NR_read, __NR_write interception - Binder hooking: intercept IPC transactions - GPU memory inspection: access GPU buffers directly ``` ### Android Kernel Source ``` - AOSP Common Kernel (ACK): google/common branch - GKI: Generic Kernel Image for Android 12+ - Vendor-specific: Qualcomm (CodeAurora), MediaTek, Samsung Exynos - Build system: build/build.sh or Bazel-based (newer) ``` ## HarmonyOS / OpenHarmony ``` - HarmonyOS (Huawei): abc file format for compiled apps - arkdecompiler: decompile HarmonyOS abc bytecode - OpenHarmony: open-source base, growing ecosystem - Security model differs from Android: distributed capabilities - Reverse engineering challenges: new bytecode VM, different IPC ``` ## Android CVE Research ### Application-Level CVEs ``` - WebView RCE (CVE-based exploit chains) - Intent redirection / deep link abuse - Content provider data leaks - Serialization vulnerabilities (Parcel, Bundle) ``` ### Kernel-Level CVEs ``` - Use-after-free in Binder driver - Privilege escalation via ion/DMA-BUF - GPU driver vulnerabilities (Adreno, Mali, PowerVR) - SELinux policy bypass chains - Reference: Android Security Bulletins (monthly) ``` ## Emulator Considerations ### Android Emulators - **LDPlayer**: Gaming focused - **BlueStacks**: Popular emulator - **NoxPlayer**: Game optimization - **MEmu**: Android gaming ### Emulator Detection ``` - Build.FINGERPRINT checks - Hardware sensor verification - File system characteristics - Performance timing ``` ## Resource Organization The README contains: - Android hooking frameworks - iOS jailbreak tools - Memory manipulation utilities - Root/jailbreak bypass tools - Mobile anti-cheat research - Emulator resources --- ## Data Source **Important**: This skill provides conceptual guidance and overview information. For detailed information use the following sources: ### 1. Project Overview & Resource Index Fetch the main README for the full curated list of repositories, tools, and descriptions: ``` https://raw.githubusercontent.com/gmh5225/awesome-game-security/refs/heads/main/README.md ``` The main README contains thousands of curated links organized by category. When users ask for specific tools, projects, or implementations, retrieve and reference the appropriate sections from this source. ### 2. Repository Code Details (Archive) For detailed repository information (file structure, source code, implementation details), the project maintains a local archive. If a repository has been archived, **always prefer fetching from the archive** over cloning or browsing GitHub directly. **Archive URL format:** ``` https://raw.githubusercontent.com/gmh5225/awesome-game-security/refs/heads/main/archive/{owner}/{repo}.txt ``` **Examples:** ```