JingMatrixandGitHub
bfc15cba62
This commit introduces a hierarchical configuration system for the security patch levels reported in attestations, allowing for both global defaults and per-package overrides. The `security_patch.txt` file is enhanced to support this new syntax. Settings at the top of the file act as a global default, which can be overridden for specific applications by defining settings under a `[package.name]` section.
137 lines
7.1 KiB
Markdown
137 lines
7.1 KiB
Markdown
# TEESimulator – A Full TEE Emulation Framework
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**TEESimulator** is a system module designed to create a complete, software-based simulation of a hardware-backed Trusted Execution Environment ([TEE](https://source.android.com/docs/security/features/trusty)) for [Key Attestation](https://developer.android.com/privacy-and-security/security-key-attestation).
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The project's goal is to move beyond simple certificate patching and build a robust framework that can create and manage virtual, self-consistent cryptographic keys.
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## ✨ Core Principles
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* **Bypass Hardware-Backed Attestation:** The primary goal of this project is to defeat Key Attestation, a security mechanism that allows apps to verify that they are running on a secure, unmodified device. This module provides the tools to bypass these checks on rooted or modified devices.
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* **Stateful Emulation:** Instead of patching responses from the real TEE, the ultimate goal is to create and manage virtual keys entirely in a simulated software environment. Any request concerning a virtual key will be handled by the simulator, ensuring perfect consistency without ever touching the real hardware.
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* **Architectural Interception:** By hooking low-level Binder IPC calls to the Keystore, the framework can transparently redirect requests for virtual keys to the software-based simulator, while allowing requests for real keys to pass through to the hardware TEE.
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* **100% FOSS:** Licensed under GPLv3, ensuring it stays free, auditable, and compliant with open-source laws.
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## 📱 Requirements
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- Android 10 or above
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## 📦 Installation & Configuration
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1. Flash this module via (Magisk / KernelSU / APatch) and reboot. It will replace [TrickyStore](https://github.com/5ec1cff/TrickyStore), [TrickyStoreOSS](https://github.com/beakthoven/TrickyStoreOSS) and their forks.
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2. (Optional) Place a hardware-backed `keybox.xml` at `/data/adb/tricky_store/keybox.xml`. This provides the cryptographic "root of trust" for the simulator.
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3. (Optional) Customize target packages in `/data/adb/tricky_store/target.txt`.
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4. (Optional) Customize the simulated security patch level in `/data/adb/tricky_store/security_patch.txt`.
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5. Enjoy!
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**All configuration files are monitored and will take effect immediately upon saving.**
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### The `keybox.xml` Root of Trust
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This file provides the master cryptographic identity for the simulator. It contains a private key and a valid, hardware-backed certificate chain from a real device. The simulator uses this to sign the virtual certificates it generates, making them appear legitimate to verifiers.
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```xml
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<?xml version="1.0"?>
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<AndroidAttestation>
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<Keybox DeviceID="...">
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<Key algorithm="ecdsa|rsa">
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<PrivateKey format="pem">...</PrivateKey>
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<CertificateChain>...</CertificateChain>
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</Key>
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</Keybox>
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</AndroidAttestation>
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```
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### Mode and Keybox Configuration (`target.txt`)
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TEESimulator currently operates in two primary modes as it transitions towards full emulation.
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You can control the simulation mode and the specific keybox.xml file used on a per-package basis.
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#### Mode Suffixes
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* **`!` → Force Generation Mode:** Creates a complete, software-based virtual key. This is the foundation of the full TEE simulation.
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* **`?` → Force Leaf Hacking Mode:** A legacy mode where a real TEE key is generated, but its attestation certificate is intercepted and modified.
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* **No symbol → Automatic Mode:** The module selects the most appropriate mode for the device.
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#### Multi-Keybox Configuration
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You can specify different keybox files for different groups of applications. This is done by adding a line with the filename in square brackets (e.g., [demo_keybox.xml]).
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All applications listed after this line will use the specified keybox file, until a new keybox is declared. Applications listed before any custom keybox declaration will use the default `keybox.xml`.
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For example:
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```
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# These two apps will use the default /data/adb/tricky_store/keybox.xml
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com.google.android.gms!
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io.github.vvb2060.keyattestation?
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# Switch to a different keybox for the following apps.
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# The file must be located at /data/adb/tricky_store/aosp_keybox.xml
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[aosp_keybox.xml]
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com.google.android.gsf
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# Switch again to another keybox.
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# The file must be located at /data/adb/tricky_store/demo_keybox.xml
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[demo_keybox.xml]
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org.matrix.demo
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```
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### Security Patch Level (`security_patch.txt`)
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This file allows you to configure the `osPatchLevel`, `vendorPatchLevel`, and `bootPatchLevel` that the simulator will report in its patched or forged attestation certificates.
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**Note:** This only affects the Key Attestation data generated by the simulator. It does not change the actual system properties of your device.
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#### Global and Per-Package Configuration
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You can set a global patch level that applies to all applications, and you can also override these settings for specific packages. The syntax is hierarchical:
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* Settings defined at the top of the file, before any `[package.name]` line, are **global** and serve as the default for all apps.
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* To create a specific configuration for an application, add its package name in square brackets (e.g., `[com.google.android.gms]`). All settings following this line will apply *only* to that package until a new package context is declared.
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#### Configuration Keys and Values
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You can specify the patch level for the following components using a `key=value` format:
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* `system`: The main OS patch level.
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* `vendor`: The vendor patch level.
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* `boot`: The boot/kernel patch level.
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* `all`: A convenient shorthand to set the same date for `system`, `vendor`, and `boot` simultaneously. Any individual key can still be used to override the value set by `all`.
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Dates should be provided in `YYYY-MM-DD` format (e.g., `2025-11-05`).
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#### Special Keywords
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In addition to date values, two special keywords provide advanced control:
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* **`no`**: This keyword instructs the simulator to **completely omit** the corresponding patch level tag from the generated attestation.
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* **`device_default`**: This keyword forces the simulator to fall back and use the device's **real hardware value** for that specific patch level. This is essential for creating exceptions to a global override or an `all` rule.
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#### Example Configuration
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This example demonstrates how to combine global settings, per-package overrides, and special keywords for fine-grained control.
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```
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# --- Global Configuration ---
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# This is the default for all apps unless specified otherwise.
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# - Forge a recent system patch level.
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# - Use the device's real vendor patch level.
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# - Do not report a boot patch level at all.
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system=2025-11-05
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vendor=device_default
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boot=no
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# --- Per-Package Override for Google Play Services ---
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# This app will report an older, specific date for its system patch.
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# It will inherit the global settings for vendor (device_default) and boot (no).
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[com.google.android.gms]
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system=2024-10-01
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# --- Per-Package Override for a Demo App ---
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# This app gets a completely custom configuration.
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[org.matrix.demo]
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# Set a base date for all patch levels...
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all=2025-09-15
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# ...but make an exception: use the real boot patch level instead of the one from 'all'.
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boot=device_default
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```
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