docs(release): bump to v4.2 with changelog and update metadata

AIDL methods use codes 1..0x00ffffff. System transactions like
PING_TRANSACTION (0x5f4e4750) fall above that range. Intercepting
pings forces a full JNI round-trip to Java and back, adding enough
latency for timing detectors to flag the ratio (3.85x vs 3.0x
threshold). Early-return for codes above LAST_CALL_TRANSACTION
eliminates this overhead while preserving all AIDL interception.

app/build.gradle.kts

@@ -29,7 +29,7 @@ val gitExecutor = objects.newInstance(GitExecutor::class.java)
 
 val gitCommitCount = gitExecutor.execute("git rev-list HEAD --count", rootDir).toInt()
 val gitCommitHash = gitExecutor.execute("git rev-parse --verify --short HEAD", rootDir)
-val verName = "v4.0"
+val verName = "v4.2"
 
 android {
     namespace = "org.matrix.TEESimulator"

app/src/main/cpp/binder_interceptor.cpp

@@ -358,6 +358,12 @@ void inspectAndRewriteTransaction(binder_transaction_data *txn_data) {
     if (txn_data->data_size > kMaxInterceptableDataSize)
         return;
 
+    // AIDL methods use codes in [FIRST_CALL_TRANSACTION, LAST_CALL_TRANSACTION] (1..0x00ffffff).
+    // System transactions (PING, INTERFACE, DUMP, SHELL_COMMAND) use codes above that range.
+    // Skip those — intercepting a ping adds measurable latency that timing detectors flag.
+    if (txn_data->code > 0x00ffffffu && txn_data->code != intercept::kBackdoorCode)
+        return;
+
     bool hijack = false;
     ThreadTransactionInfo info;
 

app/src/main/java/org/matrix/TEESimulator/interception/keystore/InterceptorUtils.kt

@@ -17,8 +17,8 @@ object InterceptorUtils {
     fun createErrorReply(errorCode: Int): BinderInterceptor.TransactionResult.OverrideReply {
         val parcel = Parcel.obtain().apply {
             writeInt(EX_SERVICE_SPECIFIC)
-            writeInt(errorCode)
             writeString(null)
+            writeInt(errorCode)
         }
         return BinderInterceptor.TransactionResult.OverrideReply(parcel)
     }

app/src/main/java/org/matrix/TEESimulator/interception/keystore/shim/KeyMintSecurityLevelInterceptor.kt

@@ -254,6 +254,18 @@ class KeyMintSecurityLevelInterceptor(
                     return InterceptorUtils.createErrorReply(KEYMINT_INVALID_INPUT_LENGTH)
                 }
 
+                if (params.any { it.tag == Tag.CREATION_DATETIME }) {
+                    SystemLogger.warning("[TX_ID: $txId] Rejecting CREATION_DATETIME in generateKey params")
+                    return InterceptorUtils.createErrorReply(RESPONSE_INVALID_ARGUMENT)
+                }
+
+                if (parsedParams.serial != null || parsedParams.imei != null ||
+                    parsedParams.meid != null || parsedParams.secondImei != null ||
+                    params.any { it.tag == Tag.DEVICE_UNIQUE_ATTESTATION }) {
+                    SystemLogger.warning("[TX_ID: $txId] Rejecting device ID attestation for uid=$callingUid")
+                    return InterceptorUtils.createErrorReply(KEYMINT_CANNOT_ATTEST_IDS)
+                }
+
                 val keyId = KeyIdentifier(callingUid, keyDescriptor.alias)
                 val isAttestKeyRequest = parsedParams.isAttestKey()
 
@@ -515,6 +527,8 @@ class KeyMintSecurityLevelInterceptor(
         // Binder buffer is ~1MB; 256KB provides 4x safety margin for transaction overhead
         private const val MAX_ALIAS_LENGTH = 256 * 1024
         private const val KEYMINT_INVALID_INPUT_LENGTH = -21
+        private const val RESPONSE_INVALID_ARGUMENT = 20
+        private const val KEYMINT_CANNOT_ATTEST_IDS = -66
         private const val MAX_CONCURRENT_HW_KEYGEN_PER_UID = 2
         // Sliding window: max hardware keygen permits per UID within the burst window
         private const val MAX_HW_KEYGEN_PER_WINDOW = 2

app/src/main/java/org/matrix/TEESimulator/pki/CertificateGenerator.kt

@@ -213,7 +213,7 @@ object CertificateGenerator {
         uid: Int,
         securityLevel: Int,
     ): Certificate {
-        val subject = params.certificateSubject ?: X500Name("CN=Android KeyStore Key")
+        val subject = params.certificateSubject ?: X500Name("CN=Android Keystore Key")
         val leafNotAfter =
             (signingKeyPair.public as? X509Certificate)?.notAfter
                 ?: Date(System.currentTimeMillis() + 31536000000L)

app/src/main/java/org/matrix/TEESimulator/util/AndroidDeviceUtils.kt

@@ -91,27 +91,33 @@ object AndroidDeviceUtils {
         attestationValueProvider: () -> ByteArray?,
         expectedSize: Int,
     ): ByteArray {
-        // 1. Attempt to get the value from the system property.
         getProperty(propertyName, expectedSize)?.let {
             SystemLogger.debug("Using $propertyName from system property: ${it.toHex()}")
+            persistToFile(propertyName, it)
             return it
         }
 
-        // 2. Fallback to the value from a cached TEE attestation.
         try {
             attestationValueProvider()?.let {
                 SystemLogger.debug("Using $propertyName from TEE attestation: ${it.toHex()}")
-                setProperty(propertyName, it) // Persist for consistency
+                setProperty(propertyName, it)
+                persistToFile(propertyName, it)
                 return it
             }
         } catch (e: Exception) {
             SystemLogger.error("Failed to get $propertyName from attestation.", e)
         }
 
-        // 3. As a final fallback, generate a random value.
+        readFromFile(propertyName, expectedSize)?.let {
+            SystemLogger.debug("Using $propertyName from persistent file: ${it.toHex()}")
+            setProperty(propertyName, it)
+            return it
+        }
+
         return generateRandomBytes(expectedSize).also {
             SystemLogger.debug("Using randomly generated $propertyName: ${it.toHex()}")
             setProperty(propertyName, it)
+            persistToFile(propertyName, it)
         }
     }
 
@@ -158,10 +164,37 @@ object AndroidDeviceUtils {
         }
     }
 
-    /** Generates a cryptographically random byte array of a specified length. */
     private fun generateRandomBytes(size: Int): ByteArray =
         ByteArray(size).also { ThreadLocalRandom.current().nextBytes(it) }
 
+    private val PERSIST_DIR = File("/data/adb/tricky_store")
+
+    private fun fileForProperty(propertyName: String): File = when (propertyName) {
+        "ro.boot.vbmeta.digest" -> File(PERSIST_DIR, "boot_hash.bin")
+        "ro.boot.vbmeta.public_key_digest" -> File(PERSIST_DIR, "boot_key.bin")
+        else -> File(PERSIST_DIR, "${propertyName.replace('.', '_')}.bin")
+    }
+
+    private fun persistToFile(propertyName: String, bytes: ByteArray) {
+        try {
+            fileForProperty(propertyName).writeBytes(bytes)
+        } catch (e: Exception) {
+            SystemLogger.error("Failed to persist $propertyName to file.", e)
+        }
+    }
+
+    private fun readFromFile(propertyName: String, expectedSize: Int): ByteArray? {
+        return try {
+            val file = fileForProperty(propertyName)
+            if (!file.exists()) return null
+            val bytes = file.readBytes()
+            if (bytes.size == expectedSize) bytes else null
+        } catch (e: Exception) {
+            SystemLogger.error("Failed to read $propertyName from file.", e)
+            null
+        }
+    }
+
     // --- Patch Level Properties ---
 
     fun getPatchLevel(uid: Int): Int {

module/changelog.md

@@ -1,3 +1,35 @@
+## TEESimulator v4.2: Detection Evasion Hardening
+
+Fixes 6 detection vectors flagged by attestation validator apps.
+
+### Attestation Policy Enforcement
+
+Replicate AOSP keystore2's `add_required_parameters()` validation that our software keygen path was bypassing:
+
+- **CREATION_DATETIME** — Reject caller-provided input with `INVALID_ARGUMENT (20)`, matching `security_level.rs:424`. Our cert gen still adds its own timestamp, same as real keystore2.
+- **Device ID attestation** — Reject ATTESTATION_ID_SERIAL, IMEI, MEID, SECOND_IMEI, and DEVICE_UNIQUE_ATTESTATION with `CANNOT_ATTEST_IDS (-66)`. No consumer app has READ_PRIVILEGED_PHONE_STATE.
+- **Error reply format** — Fixed AIDL ServiceSpecificException parcel write order (was errorCode→message, now message→errorCode).
+
+### Certificate Fix
+
+Leaf certificate Subject CN corrected from "Android KeyStore Key" to "Android Keystore Key" (lowercase s), matching AOSP `KeyGenParameterSpec.java:282`. Both Kotlin and Rust paths.
+
+### Binder Timing
+
+Skip interception for system transaction codes (PING, INTERFACE, DUMP) above LAST_CALL_TRANSACTION. Eliminates the JNI round-trip that inflated binder ping ratio to 3.85x (detector threshold: 3.0x).
+
+---
+
+## TEESimulator v4.1: Boot Identity Persistence
+
+Bugfix release. The vbmeta boot key digest was randomizing on every reboot, producing a different RootOfTrust in attestation certificates each boot.
+
+On devices where the kernel doesn't set `ro.boot.vbmeta.public_key_digest`, the fallback chain hit random generation every boot because `resetprop` overrides for `ro.boot.*` props don't survive reboots. Added file-based persistence (`boot_hash.bin`, `boot_key.bin`) between the TEE cache and random fallback. Once determined, boot identity values persist across reboots.
+
+Verified on Redmi 14C: second boot reads from persistent file instead of regenerating.
+
+---
+
 ## TEESimulator v4.0: Native Rust Cert Generation
 
 Major release. Certificate chain generation rebuilt from the ground up in Rust, replacing the BouncyCastle Java path for EC and RSA keys. Hardened against every known detector app.

module/uninstall.sh

@@ -9,3 +9,4 @@ done
 
 rm -rf "$CONFIG_DIR/persistent_keys"
 rm -f "$CONFIG_DIR/tee_status.txt"
+rm -f "$CONFIG_DIR/boot_hash.bin" "$CONFIG_DIR/boot_key.bin"

module/update.json

@@ -1,6 +1,6 @@
 {
-	"version": "v4.0",
+	"version": "v4.2",
-	"versionCode": 90,
+	"versionCode": 98,
-	"zipUrl": "https://github.com/Enginex0/TEESimulator/releases/download/v4.0/TEESimulator-v4.0-Release.zip",
+	"zipUrl": "https://github.com/Enginex0/TEESimulator/releases/download/v4.2/TEESimulator-v4.2-Release.zip",
 	"changelog": "https://raw.githubusercontent.com/Enginex0/TEESimulator/main/module/changelog.md"
 }

native-certgen/src/certbuilder.rs

@@ -51,7 +51,7 @@ fn build_leaf_cert(
     let subject_dn_der = if let Some(ref subject) = params.cert_subject {
         subject.clone()
     } else {
-        encode_simple_cn_dn("Android KeyStore Key")
+        encode_simple_cn_dn("Android Keystore Key")
     };
 
     // Validity