feat: add better error handling to prevent crashes when creating shar…

…edPreferences (#1267)

* feat: update sharedPreferences creation to properly handle creation errors gracefully

* feat: add extra error handling while using getSharedPreferences() method

* feat: add better error handling to prevent app crashes

* fix: update linting

* fix: update getSharedPreferences() implementation to create the masterKey internally

* fix: remove generated gradele files

* fix: refactor TEKStamper logic to reduce try-catch nesting

* fix: refactor TEKStamper logic to reduce try-catch nesting

* fix: fix linting

* fix: change exception variables

account-kit/rn-signer/android/src/main/java/com/accountkit/reactnativesigner/core/TEKStamper.kt

@@ -1,6 +1,7 @@
 package com.accountkit.reactnativesigner.core
 
 import android.content.Context
+import android.content.SharedPreferences
 import androidx.security.crypto.EncryptedSharedPreferences
 import androidx.security.crypto.MasterKey
 import com.accountkit.reactnativesigner.core.errors.NoInjectedBundleException
@@ -19,6 +20,8 @@ import java.nio.ByteBuffer
 import java.security.KeyFactory
 import java.security.Security
 import java.security.Signature
+import java.security.KeyStore
+import java.security.KeyStoreException
 
 @Serializable
 data class ApiStamp(val publicKey: String, val scheme: String, val signature: String)
@@ -27,6 +30,8 @@ data class Stamp(val stampHeaderName: String, val stampHeaderValue: String)
 
 private const val BUNDLE_PRIVATE_KEY = "BUNDLE_PRIVATE_KEY"
 private const val BUNDLE_PUBLIC_KEY = "BUNDLE_PUBLIC_KEY"
+private const val MASTER_KEY_ALIAS = "tek_master_key"
+private const val ENCRYPTED_SHARED_PREFERENCES_FILENAME = "tek_stamper_shared_prefs"
 
 class TEKStamper(context: Context) {
     // This is how the docs for EncryptedSharedPreferences recommend creating this setup
@@ -36,12 +41,6 @@ class TEKStamper(context: Context) {
     //
     // we should explore the best practices on how to do this once we reach a phase of further
     // cleanup
-    private val masterKey =
-        MasterKey.Builder(context.applicationContext)
-            .setKeyScheme(MasterKey.KeyScheme.AES256_GCM)
-            // requires that the phone be unlocked
-            .setUserAuthenticationRequired(false)
-            .build()
 
     /**
      * We are using EncryptedSharedPreferences to store 2 pieces of data
@@ -64,29 +63,35 @@ class TEKStamper(context: Context) {
      *
      * The open question is if the storage of the decrypted private key is secure enough though
      */
-    private val sharedPreferences =
-        EncryptedSharedPreferences.create(
-            context,
-            "tek_stamper_shared_prefs",
-            masterKey,
-            EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
-            EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM
-        )
+
 
-    private val tekManager = HpkeTEKManager(sharedPreferences)
 
-    init {
-        TinkConfig.register()
+
+
 
-        if (Security.getProvider(BouncyCastleProvider.PROVIDER_NAME).javaClass !=
-            BouncyCastleProvider::class.java
-        ) {
-            Security.removeProvider(BouncyCastleProvider.PROVIDER_NAME)
-        }
-
-        if (Security.getProvider(BouncyCastleProvider.PROVIDER_NAME) == null) {
-            Security.addProvider(BouncyCastleProvider())
+    private lateinit var tekManager: HpkeTEKManager
+    private lateinit var sharedPreferences: SharedPreferences
+
+    init {
+        try { 
+            TinkConfig.register()
+
+            sharedPreferences = getSharedPreferences(context)
+            tekManager = HpkeTEKManager(sharedPreferences)
+
+            if (Security.getProvider(BouncyCastleProvider.PROVIDER_NAME).javaClass !=
+                BouncyCastleProvider::class.java
+            ) {
+                Security.removeProvider(BouncyCastleProvider.PROVIDER_NAME)
+            }
+
+            if (Security.getProvider(BouncyCastleProvider.PROVIDER_NAME) == null) {
+                Security.addProvider(BouncyCastleProvider())
+            }
+        } catch (e: Exception){
+            throw RuntimeException("Error creating master key", e)
         }
+
     }
 
     fun init(): String {
@@ -196,4 +201,58 @@ class TEKStamper(context: Context) {
             )
         return Pair(compressedPublicKey, privateKey)
     }
+
+    private fun createSharedPreferences(masterKey: MasterKey, context: Context): SharedPreferences {
+        return EncryptedSharedPreferences.create(
+            context,
+            ENCRYPTED_SHARED_PREFERENCES_FILENAME,
+            masterKey,
+            EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
+            EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM
+        )
+    }
+
+    private fun createMasterKey(context: Context): MasterKey {
+         return MasterKey.Builder(context.applicationContext, MASTER_KEY_ALIAS)
+            .setKeyScheme(MasterKey.KeyScheme.AES256_GCM)
+            .setUserAuthenticationRequired(false)
+            .build()
+    }
+
+
+    private fun getSharedPreferences(context: Context): SharedPreferences {
+        try {
+            // Attempt to create or load the EncryptedSharedPreferences file
+            val masterKey = createMasterKey(context)
+
+            return createSharedPreferences(masterKey, context)
+        } catch(e: Exception) {
+            // Log the Exception
+            e.printStackTrace()
+        }
+
+        // An error occured creating or retrieving the Shared Preferences file.
+        // Delete the existing master key and EncryptedSharedPreferences
+
+        // first delete the MasterKey
+        try {
+            val keyStore = KeyStore.getInstance("AndroidKeyStore")
+            keyStore.load(null)
+            keyStore.deleteEntry(MASTER_KEY_ALIAS)
+        } catch (keyStoreDeletionException: Exception) {
+            throw RuntimeException("An error occured deleting the Master Key", keyStoreDeletionException)
+        }
+
+        // attempt to recreate a new EncryptedSharedPreferences file
+        try {
+            // Create a new MasterKey
+            val newMasterKey = createMasterKey(context)
+            context.getSharedPreferences(ENCRYPTED_SHARED_PREFERENCES_FILENAME, Context.MODE_PRIVATE).edit().clear().apply()
+            context.deleteSharedPreferences(ENCRYPTED_SHARED_PREFERENCES_FILENAME)
+
+            return createSharedPreferences(newMasterKey, context)
+        } catch(retryException: Exception) {
+            throw RuntimeException("Couldn't create the required shared preferences file. Ensure you are properly authenticated on this device.", retryException)
+        }
+    }
 }

account-kit/rn-signer/example/metro.config.js

@@ -3,20 +3,46 @@ const { getDefaultConfig } = require("@react-native/metro-config");
 const { getConfig } = require("react-native-builder-bob/metro-config");
 const pkg = require("../package.json");
 
-const root = path.resolve(__dirname, "..");
+const rnSignerRoot = path.resolve(__dirname, "..");
+const projectRoot = __dirname;
 // handles the hoisted modules
 const repoRoot = path.resolve(__dirname, "../../..");
 
+const config = getDefaultConfig(projectRoot);
+
+const monorepoPackages = {
+  "@account-kit/signer": path.resolve(repoRoot, "account-kit/signer"),
+  "@aa-sdk/core": path.resolve(repoRoot, "aa-sdk/core"),
+  "@account-kit/logging": path.resolve(repoRoot, "account-kit/logging"),
+};
+
+config.watchFolders = [
+  projectRoot,
+  rnSignerRoot,
+  ...Object.values(monorepoPackages),
+];
+
+// Let Metro know where to resolve packages and in what order
+config.resolver.nodeModulesPaths = [
+  path.resolve(projectRoot, "node_modules"),
+  path.resolve(rnSignerRoot, "node_modules"),
+  path.resolve(repoRoot, "node_modules"),
+];
+
+// Force Metro to resolve (sub)dependencies only from the `nodeModulesPaths`
+config.resolver.disableHierarchicalLookup = true;
+
+config.resolver.extraNodeModules = {
+  ...config.resolver.extraNodeModules,
+  ...require("node-libs-react-native"),
+  ...monorepoPackages,
+  crypto: require.resolve("crypto-browserify"),
+  stream: require.resolve("stream-browserify"),
+};
+
 /**
  * Metro configuration
  * https://facebook.github.io/metro/docs/configuration
  *
  */
-module.exports = {
-  ...getConfig(getDefaultConfig(__dirname), {
-    root,
-    pkg,
-    project: __dirname,
-  }),
-  watchFolders: [root, repoRoot],
-};
+module.exports = config;