Enginex0
684542f4b1
doSoftwareKeyGen's symmetric branch (AES/HMAC/3DES) previously did two things wrong: 1. It accepted attestationKey != null silently and then ignored the reference: the symmetric path never consults attestationKey, so a caller asking for BYO on a symmetric key would have received a key with no certificate chain and no signal that BYO was dropped. Reject early with KEYMINT_INVALID_ARGUMENT matching real KeyMint HAL behavior. 2. The unsupported-algorithm path (e.g. 3DES, which has no JCA mapping in this branch) threw SECURE_HW_COMMUNICATION_FAILED (-49), the same numeric code InterceptorUtils labels as Error::Km(UNSUPPORTED_TAG). That confuses diagnosis since -49 is exactly the symptom the BYO fix series was just chasing. Use KEYMINT_INVALID_ARGUMENT (-38) which is what real KeyMint returns for unsupported algorithms in this context. Surfaced by adversarial audit of 66a8c7f's broadened forceGenerate gate, which now routes any attestationKey != null to software unconditionally.
TEESimulator-RS
Full TEE Emulation for Rooted Android
Note
Fork of JingMatrix/TEESimulator with native Rust certificate generation, key persistence, and AOSP-compliant attestation behavior. For the upstream project, see the original repo.
What It Does
TEESimulator intercepts Binder IPC at the ioctl level inside the keystore2 process and generates entire certificate chains from scratch, signed by your keybox, with correct attestation extensions. Apps that verify hardware attestation see a legitimate device.
This is not TrickyStore. TEESimulator replaces TrickyStore and its forks entirely. It shares the same config paths for drop-in compatibility, but the internals are different: native Rust cert generation, binder-level interception via lsplt, per-UID rate limiting, key persistence, and AOSP-spec attestation behavior.
Requirements
Important
A valid
keybox.xmlis required for hardware-level attestation. Without one, the module generates software-level certificates that won't pass strict hardware checks.
- Android 10+
- Root manager: KernelSU, Magisk, or APatch
keybox.xmlat/data/adb/tricky_store/keybox.xml
Quick Start
- Download the latest ZIP from Releases
- Install via your root manager and reboot
- Place your keybox at
/data/adb/tricky_store/keybox.xml - Configure targets in
/data/adb/tricky_store/target.txt - Verify with Play Integrity or Key Attestation Demo
Architecture
Native Cert Generation — libcertgen.so generates X.509 chains in Rust using ring and manual DER encoding. BouncyCastle fallback for unsupported curves (P-224, P-521, Curve25519).
Binder Interception — PLT hook on ioctl() in libc.so via lsplt inside keystore2. Intercepts generateKey, importKey, and getKeyEntry transactions.
AOSP Compliance — Self-signed certs for non-attested keys (matching ta/src/keys.rs), correct AuthorizationList tag ordering, version-guarded extension fields, authorize_create enforcement.
Key Persistence — Generated keys survive reboots. File-backed with file-level locking.
Rate Limiting — Per-UID hardware keygen cap (2/30s window, 2 concurrent). Overflow falls to software certs.
Configuration
All config files live at /data/adb/tricky_store/ and are hot-reloaded via FileObserver.
target.txt
Controls which apps get intercepted and the simulation mode.
| Suffix | Mode |
|---|---|
! |
Force software key generation |
? |
Force leaf certificate patching (real TEE key, patched cert) |
| (none) | Automatic selection |
Multi-keybox support via [filename.xml] headers:
com.google.android.gms!
io.github.vvb2060.keyattestation?
[aosp_keybox.xml]
com.google.android.gsf
security_patch.txt
Override patch levels reported in attestation certificates. Global defaults at top, per-package overrides with [package.name].
| Key | Scope |
|---|---|
system |
OS patch level |
vendor |
Vendor patch level |
boot |
Boot/kernel patch level |
all |
Sets all three |
Special values: today, YYYY-MM-DD templates, no (omit tag), device_default, prop (read from system property).
system=YYYY-MM-05
vendor=device_default
boot=no
[com.google.android.gms]
system=2025-10-01
Building from Source
Prerequisites: JDK 21, Android SDK/NDK 27, Rust stable with aarch64-linux-android target, cargo-ndk.
git clone --recursive https://github.com/Enginex0/TEESimulator-RS.git
cd TEESimulator-RS
./gradlew zipRelease zipDebug
Output ZIPs in out/. Gradle invokes cargo ndk automatically to cross-compile libcertgen.so.
Push to main or use Actions > Build > Run workflow to trigger CI.
Compatibility
| Root Manager | Status |
|---|---|
| KernelSU | Tested (Action button + lifecycle scripts) |
| Magisk | Supported |
| APatch | Supported |
Community
Credits
- JingMatrix — original TEESimulator and interception architecture
- 5ec1cff — TrickyStore, the project that pioneered keystore interception
- LSPlt — PLT hook library
- ring — Rust cryptography library
- MhmRdd — AOSP compliance work via upstream PR #157
- fatalcoder524 — contributor and collaborator
- huguangares — collaborator and tester