fix(interception): harden daemon against binder stress crashes

BinderInterceptor.onTransact now catches Throwable, preventing any
exception on a binder thread from killing the daemon. Adds a global
uncaught exception handler as defense in depth.

Replace Thread.sleep with TeeLatencySimulator (LockSupport.parkNanos +
statistical delay model) for keygen latency, reducing binder thread
blocking. Move GeneratedKeyPersistence.save to a background executor
to avoid disk I/O on binder threads.

Convert force-unwrap parcel reads to safe calls with early returns in
onPreTransact/onPostTransact hot paths. Add -DNDEBUG to native release
builds to compile out verbose logging from the ioctl hook.

Targets G2 (ping overhead) and G10 (stress attestation consistency).

app/src/main/cpp/CMakeLists.txt

@@ -5,6 +5,7 @@ set(CMAKE_CXX_STANDARD 23)
 set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fno-rtti")
 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fno-exceptions")
+set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -DNDEBUG")
 
 # LSPlt configuration
 OPTION(LSPLT_BUILD_SHARED OFF)

app/src/main/java/org/matrix/TEESimulator/App.kt

@@ -33,8 +33,11 @@ object App {
     fun main(args: Array<String>) {
         SystemLogger.info("Welcome to TEESimulator!")
 
+        Thread.setDefaultUncaughtExceptionHandler { thread, throwable ->
+            SystemLogger.error("Uncaught exception on ${thread.name}", throwable)
+        }
+
         try {
-            // Initialize the Android framework environment
             prepareEnvironment()
             // Initialize and start the appropriate keystore interceptors.
             initializeInterceptors()

app/src/main/java/org/matrix/TEESimulator/interception/core/BinderInterceptor.kt

@@ -109,17 +109,17 @@ abstract class BinderInterceptor : Binder() {
      * `handlePostTransact`).
      */
     final override fun onTransact(code: Int, data: Parcel, reply: Parcel?, flags: Int): Boolean {
-        // The native hook prepends a transaction ID to the data parcel.
         val txId = data.readLong()
-        val result =
+        val result = try {
             when (code) {
-                // These codes are defined in the native layer to distinguish hook types.
                 PRE_TRANSACT_CODE -> handlePreTransact(txId, data)
                 POST_TRANSACT_CODE -> handlePostTransact(txId, data)
                 else -> return super.onTransact(code, data, reply, flags)
             }
-
-        // The reply parcel is guaranteed to be non-null for our custom transactions.
+        } catch (e: Throwable) {
+            SystemLogger.error("[TX_ID: $txId] Interceptor exception, falling through to HAL", e)
+            TransactionResult.ContinueAndSkipPost
+        }
         writeResultToReply(result, reply!!)
         return true
     }

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

@@ -22,7 +22,9 @@ import java.security.cert.CertificateFactory
 import java.security.spec.PKCS8EncodedKeySpec
 import java.util.concurrent.ConcurrentHashMap
 import java.util.concurrent.ConcurrentLinkedDeque
+import java.util.concurrent.Executors
 import java.util.concurrent.atomic.AtomicInteger
+import java.util.concurrent.locks.LockSupport
 import org.matrix.TEESimulator.attestation.AttestationBuilder
 import org.matrix.TEESimulator.attestation.AttestationConstants
 import org.matrix.TEESimulator.attestation.AttestationPatcher
@@ -39,6 +41,7 @@ import org.matrix.TEESimulator.pki.KeyBoxManager
 import org.matrix.TEESimulator.pki.NativeCertGen
 import org.matrix.TEESimulator.util.AndroidDeviceUtils
 import org.matrix.TEESimulator.util.AndroidPermissionUtils
+import org.matrix.TEESimulator.util.TeeLatencySimulator
 
 class KeyMintSecurityLevelInterceptor(
     private val original: IKeystoreSecurityLevel,
@@ -82,7 +85,8 @@ class KeyMintSecurityLevelInterceptor(
                 logTransaction(txId, transactionNames[code]!!, callingUid, callingPid)
 
                 data.enforceInterface(IKeystoreSecurityLevel.DESCRIPTOR)
-                val keyDescriptor = data.readTypedObject(KeyDescriptor.CREATOR)!!
+                val keyDescriptor = data.readTypedObject(KeyDescriptor.CREATOR)
+                    ?: return TransactionResult.ContinueAndSkipPost
                 SystemLogger.info(
                     "[TX_ID: $txId] Forward to post-importKey hook for ${keyDescriptor.alias}[${keyDescriptor.nspace}]"
                 )
@@ -161,8 +165,10 @@ class KeyMintSecurityLevelInterceptor(
             logTransaction(txId, "post-${transactionNames[code]!!}", callingUid, callingPid)
 
             data.enforceInterface(IKeystoreSecurityLevel.DESCRIPTOR)
-            val keyDescriptor = data.readTypedObject(KeyDescriptor.CREATOR)!!
-            val params = data.createTypedArray(KeyParameter.CREATOR)!!
+            val keyDescriptor = data.readTypedObject(KeyDescriptor.CREATOR)
+                ?: return TransactionResult.SkipTransaction
+            val params = data.createTypedArray(KeyParameter.CREATOR)
+                ?: return TransactionResult.SkipTransaction
             val parsedParams = KeyMintAttestation(params)
             val forced = data.readBoolean()
             if (forced)
@@ -170,7 +176,8 @@ class KeyMintSecurityLevelInterceptor(
                     "[TX_ID: $txId] Current operation has a very high pruning power."
                 )
             val response: CreateOperationResponse =
-                reply.readTypedObject(CreateOperationResponse.CREATOR)!!
+                reply.readTypedObject(CreateOperationResponse.CREATOR)
+                    ?: return TransactionResult.SkipTransaction
             SystemLogger.verbose(
                 "[TX_ID: $txId] CreateOperationResponse: ${response.iOperation} ${response.operationChallenge}"
             )
@@ -206,8 +213,10 @@ class KeyMintSecurityLevelInterceptor(
 
                 // Cache the newly patched chain to ensure consistency across subsequent API calls.
                 data.enforceInterface(IKeystoreSecurityLevel.DESCRIPTOR)
-                val keyDescriptor = data.readTypedObject(KeyDescriptor.CREATOR)!!
-                val key = metadata.key!!
+                val keyDescriptor = data.readTypedObject(KeyDescriptor.CREATOR)
+                    ?: return TransactionResult.SkipTransaction
+                val key = metadata.key
+                    ?: return TransactionResult.SkipTransaction
                 val keyId = KeyIdentifier(callingUid, keyDescriptor.alias)
                 CertificateHelper.updateCertificateChain(metadata, newChain).getOrThrow()
                 metadata.authorizations =
@@ -547,10 +556,12 @@ class KeyMintSecurityLevelInterceptor(
             }
             generatedKeys[keyId] = GeneratedKeyInfo(null, secretKey, keyDescriptor.nspace, response, parsedParams)
 
-            val elapsedMs = (System.nanoTime() - genStartNanos) / 1_000_000
-            val floor = if (securityLevel == SecurityLevel.STRONGBOX) STRONGBOX_KEYGEN_LATENCY_FLOOR_MS else TEE_LATENCY_FLOOR_MS
-            val delayMs = floor - elapsedMs
-            if (delayMs > 0) Thread.sleep(delayMs)
+            if (securityLevel == SecurityLevel.STRONGBOX) {
+                val delayMs = STRONGBOX_KEYGEN_LATENCY_FLOOR_MS - (System.nanoTime() - genStartNanos) / 1_000_000
+                if (delayMs > 0) LockSupport.parkNanos(delayMs * 1_000_000)
+            } else {
+                TeeLatencySimulator.simulateGenerateKeyDelay(parsedParams.algorithm, System.nanoTime() - genStartNanos)
+            }
 
             return InterceptorUtils.createTypedObjectReply(metadata)
         }
@@ -570,12 +581,14 @@ class KeyMintSecurityLevelInterceptor(
         generatedKeys[keyId] = GeneratedKeyInfo(keyData.first, null, keyDescriptor.nspace, response, parsedParams)
         if (isAttestKeyRequest) attestationKeys.add(keyId)
 
+        val certChainCopy = keyData.second.toList()
+        persistExecutor.execute {
             GeneratedKeyPersistence.save(
                 keyId = keyId,
                 keyPair = keyData.first,
                 nspace = keyDescriptor.nspace,
                 securityLevel = securityLevel,
-            certChain = keyData.second.toList(),
+                certChain = certChainCopy,
                 algorithm = parsedParams.algorithm,
                 keySize = parsedParams.keySize,
                 ecCurve = parsedParams.ecCurve ?: 0,
@@ -583,11 +596,14 @@ class KeyMintSecurityLevelInterceptor(
                 digests = parsedParams.digest,
                 isAttestationKey = isAttestKeyRequest,
             )
+        }
 
-        val elapsedMs = (System.nanoTime() - genStartNanos) / 1_000_000
-        val floor = if (securityLevel == SecurityLevel.STRONGBOX) STRONGBOX_KEYGEN_LATENCY_FLOOR_MS else TEE_LATENCY_FLOOR_MS
-        val delayMs = floor - elapsedMs
-        if (delayMs > 0) Thread.sleep(delayMs)
+        if (securityLevel == SecurityLevel.STRONGBOX) {
+            val delayMs = STRONGBOX_KEYGEN_LATENCY_FLOOR_MS - (System.nanoTime() - genStartNanos) / 1_000_000
+            if (delayMs > 0) LockSupport.parkNanos(delayMs * 1_000_000)
+        } else {
+            TeeLatencySimulator.simulateGenerateKeyDelay(parsedParams.algorithm, System.nanoTime() - genStartNanos)
+        }
 
         return InterceptorUtils.createTypedObjectReply(response.metadata)
     }
@@ -875,6 +891,8 @@ class KeyMintSecurityLevelInterceptor(
                 .associate { field -> (field.get(null) as Int) to field.name.split("_")[1] }
         }
 
+        private val persistExecutor = Executors.newSingleThreadExecutor()
+
         val generatedKeys = ConcurrentHashMap<KeyIdentifier, GeneratedKeyInfo>()
         val teeResponses = ConcurrentHashMap<KeyIdentifier, KeyEntryResponse>()
         val patchedChains = ConcurrentHashMap<KeyIdentifier, Array<Certificate>>()

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

@@ -9,6 +9,7 @@ import android.hardware.security.keymint.KeyPurpose
 import android.hardware.security.keymint.PaddingMode
 import android.hardware.security.keymint.Tag
 import android.os.ServiceSpecificException
+import java.util.concurrent.locks.LockSupport
 import android.system.keystore2.IKeystoreOperation
 import android.system.keystore2.KeyParameters
 import java.security.KeyPair
@@ -275,7 +276,7 @@ class SoftwareOperation(
             if (latencyFloorMs > 0) {
                 val elapsedMs = (System.nanoTime() - startNs) / 1_000_000
                 val delayMs = latencyFloorMs - elapsedMs
-                if (delayMs > 0) Thread.sleep(delayMs)
+                if (delayMs > 0) LockSupport.parkNanos(delayMs * 1_000_000)
             }
             finalized = true
             onFinishCallback?.invoke()