移除java代码

app/AndroidManifest.xml

@@ -219,16 +219,6 @@
                 <category android:name="android.intent.category.default" />
             </intent-filter>
         </service>
-        <service
-            android:name="com.jc.jcfw.accountmanager.AuthenticatorService"
-            >
-            <intent-filter>
-                <action android:name="android.accounts.AccountAuthenticator" />
-            </intent-filter>
-            <meta-data android:name="android.accounts.AccountAuthenticator"
-                android:resource="@xml/authenticator" />
-        </service>
-
 </application>
     <supports-screens
         android:anyDensity="true"

app/src/com/ctf/games/release/activity/BiometricActivity.kt

@@ -52,14 +52,14 @@ class BiometricActivity : AppCompatActivity() {
           }
           val encryptedData = cryptographyManager!!.encryptData(text, _result.cipher)
           val encryptedString =
-            Base64.encodeToString(encryptedData.ciphertext, Base64.DEFAULT)
+            Base64.encodeToString(encryptedData!!.ciphertext, Base64.DEFAULT)
           val ivString =
             Base64.encodeToString(encryptedData.initializationVector, Base64.DEFAULT)
           Log.i(TAG, "encrypted msg: $encryptedString")
           Log.i(TAG, "encrypted iv: $ivString")
           finish()
         }
-      biometricPrompt.authenticate(promptInfo!!, BiometricPrompt.CryptoObject(cipher))
+      biometricPrompt.authenticate(promptInfo!!, BiometricPrompt.CryptoObject(cipher!!))
     }
   }
 
@@ -84,7 +84,7 @@ class BiometricActivity : AppCompatActivity() {
           Log.i(TAG, "decrypted msg: $decryptedMsg")
           finish()
         }
-      biometricPrompt.authenticate(promptInfo!!, BiometricPrompt.CryptoObject(cipher))
+      biometricPrompt.authenticate(promptInfo!!, BiometricPrompt.CryptoObject(cipher!!))
     }
   }
 

app/src/com/jc/jcfw/accountmanager/Authenticator.java

@@ -1,56 +0,0 @@
-package com.jc.jcfw.accountmanager;
-
-import android.accounts.AbstractAccountAuthenticator;
-import android.accounts.Account;
-import android.accounts.AccountAuthenticatorResponse;
-import android.accounts.NetworkErrorException;
-import android.content.Context;
-import android.os.Bundle;
-
-/**
- * Created by sebastian on 07-03-16.
- */
-public class Authenticator extends AbstractAccountAuthenticator {
-
-  private Context context;
-
-  public Authenticator(Context context) {
-    super(context);
-    this.context = context;
-  }
-
-  @Override
-  public Bundle editProperties(AccountAuthenticatorResponse response, String accountType) {
-    return null;
-  }
-
-  @Override
-  public Bundle addAccount(AccountAuthenticatorResponse response, String accountType, String authTokenType, String[] requiredFeatures, Bundle options) throws NetworkErrorException {
-    return null;
-  }
-
-  @Override
-  public Bundle confirmCredentials(AccountAuthenticatorResponse response, Account account, Bundle options) throws NetworkErrorException {
-    return null;
-  }
-
-  @Override
-  public Bundle getAuthToken(AccountAuthenticatorResponse response, Account account, String authTokenType, Bundle options) throws NetworkErrorException {
-    return null;
-  }
-
-  @Override
-  public String getAuthTokenLabel(String authTokenType) {
-    return authTokenType;
-  }
-
-  @Override
-  public Bundle updateCredentials(AccountAuthenticatorResponse response, Account account, String authTokenType, Bundle options) throws NetworkErrorException {
-    return null;
-  }
-
-  @Override
-  public Bundle hasFeatures(AccountAuthenticatorResponse response, Account account, String[] features) throws NetworkErrorException {
-    return null;
-  }
-}

app/src/com/jc/jcfw/accountmanager/AuthenticatorService.java

@@ -1,19 +0,0 @@
-package com.jc.jcfw.accountmanager;
-
-import android.app.Service;
-import android.content.Intent;
-import android.os.IBinder;
-
-public class AuthenticatorService extends Service {
-  private Authenticator authenticator;
-
-  @Override
-  public void onCreate() {
-    authenticator = new Authenticator(this);
-  }
-
-  @Override
-  public IBinder onBind(Intent intent) {
-    return authenticator.getIBinder();
-  }
-}

app/src/com/jc/jcfw/appauth/AuthStateManager.java

@@ -1,150 +0,0 @@
-package com.jc.jcfw.appauth;
-
-import android.content.Context;
-import android.content.SharedPreferences;
-import android.util.Log;
-
-import net.openid.appauth.AuthState;
-import net.openid.appauth.AuthorizationException;
-import net.openid.appauth.AuthorizationResponse;
-import net.openid.appauth.RegistrationResponse;
-import net.openid.appauth.TokenResponse;
-
-import org.json.JSONException;
-
-import java.lang.ref.WeakReference;
-import java.util.concurrent.atomic.AtomicReference;
-import java.util.concurrent.locks.ReentrantLock;
-
-import androidx.annotation.AnyThread;
-import androidx.annotation.NonNull;
-import androidx.annotation.Nullable;
-
-public class AuthStateManager {
-
-  private static final AtomicReference<WeakReference<AuthStateManager>> INSTANCE_REF =
-      new AtomicReference<>(new WeakReference<>(null));
-
-  private static final String TAG = "AuthStateManager";
-
-  private static final String STORE_NAME = "AuthState";
-  private static final String KEY_STATE = "state";
-
-  private final SharedPreferences mPrefs;
-  private final ReentrantLock mPrefsLock;
-  private final AtomicReference<AuthState> mCurrentAuthState;
-
-  @AnyThread
-  public static AuthStateManager getInstance(@NonNull Context context) {
-    AuthStateManager manager = INSTANCE_REF.get().get();
-    if (manager == null) {
-      manager = new AuthStateManager(context.getApplicationContext());
-      INSTANCE_REF.set(new WeakReference<>(manager));
-    }
-
-    return manager;
-  }
-
-  private AuthStateManager(Context context) {
-    mPrefs = context.getSharedPreferences(STORE_NAME, Context.MODE_PRIVATE);
-    mPrefsLock = new ReentrantLock();
-    mCurrentAuthState = new AtomicReference<>();
-  }
-
-  @AnyThread
-  @NonNull
-  public AuthState getCurrent() {
-    if (mCurrentAuthState.get() != null) {
-      return mCurrentAuthState.get();
-    }
-
-    AuthState state = readState();
-    if (mCurrentAuthState.compareAndSet(null, state)) {
-      return state;
-    } else {
-      return mCurrentAuthState.get();
-    }
-  }
-
-  @AnyThread
-  @NonNull
-  public AuthState replace(@NonNull AuthState state) {
-    writeState(state);
-    mCurrentAuthState.set(state);
-    return state;
-  }
-
-  @AnyThread
-  @NonNull
-  public AuthState updateAfterAuthorization(
-      @Nullable AuthorizationResponse response,
-      @Nullable AuthorizationException ex) {
-    AuthState current = getCurrent();
-    current.update(response, ex);
-    return replace(current);
-  }
-
-  @AnyThread
-  @NonNull
-  public AuthState updateAfterTokenResponse(
-      @Nullable TokenResponse response,
-      @Nullable AuthorizationException ex) {
-    AuthState current = getCurrent();
-    current.update(response, ex);
-    return replace(current);
-  }
-
-  @AnyThread
-  @NonNull
-  public AuthState updateAfterRegistration(
-      RegistrationResponse response,
-      AuthorizationException ex) {
-    AuthState current = getCurrent();
-    if (ex != null) {
-      return current;
-    }
-
-    current.update(response);
-    return replace(current);
-  }
-
-  @AnyThread
-  @NonNull
-  private AuthState readState() {
-    mPrefsLock.lock();
-    try {
-      String currentState = mPrefs.getString(KEY_STATE, null);
-      if (currentState == null) {
-        return new AuthState();
-      }
-
-      try {
-        return AuthState.jsonDeserialize(currentState);
-      } catch (JSONException ex) {
-        Log.w(TAG, "Failed to deserialize stored auth state - discarding");
-        return new AuthState();
-      }
-    } finally {
-      mPrefsLock.unlock();
-    }
-  }
-
-  @AnyThread
-  private void writeState(@Nullable AuthState state) {
-    mPrefsLock.lock();
-    try {
-      SharedPreferences.Editor editor = mPrefs.edit();
-      if (state == null) {
-        editor.remove(KEY_STATE);
-      } else {
-        editor.putString(KEY_STATE, state.jsonSerializeString());
-      }
-
-      if (!editor.commit()) {
-        throw new IllegalStateException("Failed to write state to shared prefs");
-      }
-    } finally {
-      mPrefsLock.unlock();
-    }
-  }
-}

app/src/com/jc/jcfw/appauth/AuthStateManager.kt

@@ -0,0 +1,130 @@
+package com.jc.jcfw.appauth
+
+import android.content.Context
+import android.content.SharedPreferences
+import android.util.Log
+import androidx.annotation.AnyThread
+import net.openid.appauth.AuthState
+import net.openid.appauth.AuthorizationException
+import net.openid.appauth.AuthorizationResponse
+import net.openid.appauth.RegistrationResponse
+import net.openid.appauth.TokenResponse
+import org.json.JSONException
+import java.lang.ref.WeakReference
+import java.util.concurrent.atomic.AtomicReference
+import java.util.concurrent.locks.ReentrantLock
+
+class AuthStateManager private constructor(context: Context) {
+  private val mPrefs: SharedPreferences
+  private val mPrefsLock: ReentrantLock
+  private val mCurrentAuthState: AtomicReference<AuthState>
+
+  init {
+    mPrefs = context.getSharedPreferences(STORE_NAME, Context.MODE_PRIVATE)
+    mPrefsLock = ReentrantLock()
+    mCurrentAuthState = AtomicReference()
+  }
+
+  @get:AnyThread
+  val current: AuthState
+    get() {
+      if (mCurrentAuthState.get() != null) {
+        return mCurrentAuthState.get()
+      }
+      val state = readState()
+      return if (mCurrentAuthState.compareAndSet(null, state)) {
+        state
+      } else {
+        mCurrentAuthState.get()
+      }
+    }
+
+  @AnyThread
+  fun replace(state: AuthState): AuthState {
+    writeState(state)
+    mCurrentAuthState.set(state)
+    return state
+  }
+
+  @AnyThread
+  fun updateAfterAuthorization(
+    response: AuthorizationResponse?,
+    ex: AuthorizationException?
+  ): AuthState {
+    val current = current
+    current.update(response, ex)
+    return replace(current)
+  }
+
+  @AnyThread
+  fun updateAfterTokenResponse(
+    response: TokenResponse?,
+    ex: AuthorizationException?
+  ): AuthState {
+    val current = current
+    current.update(response, ex)
+    return replace(current)
+  }
+
+  @AnyThread
+  fun updateAfterRegistration(
+    response: RegistrationResponse?,
+    ex: AuthorizationException?
+  ): AuthState {
+    val current = current
+    if (ex != null) {
+      return current
+    }
+    current.update(response)
+    return replace(current)
+  }
+
+  @AnyThread
+  private fun readState(): AuthState {
+    mPrefsLock.lock()
+    return try {
+      val currentState = mPrefs.getString(KEY_STATE, null)
+        ?: return AuthState()
+      try {
+        AuthState.jsonDeserialize(currentState)
+      } catch (ex: JSONException) {
+        Log.w(TAG, "Failed to deserialize stored auth state - discarding")
+        AuthState()
+      }
+    } finally {
+      mPrefsLock.unlock()
+    }
+  }
+
+  @AnyThread
+  private fun writeState(state: AuthState?) {
+    mPrefsLock.lock()
+    try {
+      val editor = mPrefs.edit()
+      if (state == null) {
+        editor.remove(KEY_STATE)
+      } else {
+        editor.putString(KEY_STATE, state.jsonSerializeString())
+      }
+      check(editor.commit()) { "Failed to write state to shared prefs" }
+    } finally {
+      mPrefsLock.unlock()
+    }
+  }
+
+  companion object {
+    private val INSTANCE_REF = AtomicReference(WeakReference<AuthStateManager?>(null))
+    private const val TAG = "AuthStateManager"
+    private const val STORE_NAME = "AuthState"
+    private const val KEY_STATE = "state"
+    @AnyThread
+    fun getInstance(context: Context): AuthStateManager {
+      var manager = INSTANCE_REF.get().get()
+      if (manager == null) {
+        manager = AuthStateManager(context.applicationContext)
+        INSTANCE_REF.set(WeakReference(manager))
+      }
+      return manager
+    }
+  }
+}

app/src/com/jc/jcfw/appauth/ConnectionBuilderForTesting.java

@@ -1,108 +0,0 @@
-package com.jc.jcfw.appauth;
-
-import android.annotation.SuppressLint;
-import android.net.Uri;
-import android.util.Log;
-
-import net.openid.appauth.Preconditions;
-import net.openid.appauth.connectivity.ConnectionBuilder;
-
-import java.io.IOException;
-import java.net.HttpURLConnection;
-import java.net.URL;
-import java.security.KeyManagementException;
-import java.security.NoSuchAlgorithmException;
-import java.security.cert.X509Certificate;
-import java.util.concurrent.TimeUnit;
-
-import javax.net.ssl.HostnameVerifier;
-import javax.net.ssl.HttpsURLConnection;
-import javax.net.ssl.SSLContext;
-import javax.net.ssl.SSLSession;
-import javax.net.ssl.TrustManager;
-import javax.net.ssl.X509TrustManager;
-
-import androidx.annotation.NonNull;
-import androidx.annotation.Nullable;
-
-public final class ConnectionBuilderForTesting implements ConnectionBuilder {
-
-   public static final ConnectionBuilderForTesting INSTANCE = new ConnectionBuilderForTesting();
-
-   private static final String TAG = "ConnBuilder";
-
-   private static final int CONNECTION_TIMEOUT_MS = (int) TimeUnit.SECONDS.toMillis(15);
-   private static final int READ_TIMEOUT_MS = (int) TimeUnit.SECONDS.toMillis(10);
-
-   private static final String HTTP = "http";
-   private static final String HTTPS = "https";
-
-   @SuppressLint("TrustAllX509TrustManager")
-   private static final TrustManager[] ANY_CERT_MANAGER = new TrustManager[] {
-       new X509TrustManager() {
-          public X509Certificate[] getAcceptedIssuers() {
-             return null;
-          }
-
-          public void checkClientTrusted(X509Certificate[] certs, String authType) {}
-
-          public void checkServerTrusted(X509Certificate[] certs, String authType) {}
-       }
-   };
-
-   @SuppressLint("BadHostnameVerifier")
-   private static final HostnameVerifier ANY_HOSTNAME_VERIFIER = new HostnameVerifier() {
-      public boolean verify(String hostname, SSLSession session) {
-         return true;
-      }
-   };
-
-   @Nullable
-   private static final SSLContext TRUSTING_CONTEXT;
-
-   static {
-      SSLContext context;
-      try {
-         context = SSLContext.getInstance("SSL");
-      } catch (NoSuchAlgorithmException e) {
-         Log.e("ConnBuilder", "Unable to acquire SSL context");
-         context = null;
-      }
-
-      SSLContext initializedContext = null;
-      if (context != null) {
-         try {
-            context.init(null, ANY_CERT_MANAGER, new java.security.SecureRandom());
-            initializedContext = context;
-         } catch (KeyManagementException e) {
-            Log.e(TAG, "Failed to initialize trusting SSL context");
-         }
-      }
-
-      TRUSTING_CONTEXT = initializedContext;
-   }
-
-   private ConnectionBuilderForTesting() {
-      // no need to construct new instances
-   }
-
-   @NonNull
-   @Override
-   public HttpURLConnection openConnection(@NonNull Uri uri) throws IOException {
-      Preconditions.checkNotNull(uri, "url must not be null");
-      Preconditions.checkArgument(HTTP.equals(uri.getScheme()) || HTTPS.equals(uri.getScheme()),
-          "scheme or uri must be http or https");
-      HttpURLConnection conn = (HttpURLConnection) new URL(uri.toString()).openConnection();
-      conn.setConnectTimeout(CONNECTION_TIMEOUT_MS);
-      conn.setReadTimeout(READ_TIMEOUT_MS);
-      conn.setInstanceFollowRedirects(false);
-
-      if (conn instanceof HttpsURLConnection && TRUSTING_CONTEXT != null) {
-         HttpsURLConnection httpsConn = (HttpsURLConnection) conn;
-         httpsConn.setSSLSocketFactory(TRUSTING_CONTEXT.getSocketFactory());
-         httpsConn.setHostnameVerifier(ANY_HOSTNAME_VERIFIER);
-      }
-
-      return conn;
-   }
-}

app/src/com/jc/jcfw/appauth/JConfiguration.java

@@ -1,310 +0,0 @@
-package com.jc.jcfw.appauth;
-
-import android.content.Context;
-import android.content.Intent;
-import android.content.SharedPreferences;
-import android.content.res.Resources;
-import android.net.Uri;
-import android.text.TextUtils;
-
-import com.ctf.games.release.R;
-
-import net.openid.appauth.connectivity.ConnectionBuilder;
-import net.openid.appauth.connectivity.DefaultConnectionBuilder;
-
-import org.json.JSONException;
-import org.json.JSONObject;
-
-import java.io.IOException;
-import java.lang.ref.WeakReference;
-import java.nio.charset.StandardCharsets;
-
-import androidx.annotation.NonNull;
-import androidx.annotation.Nullable;
-import okio.Buffer;
-import okio.BufferedSource;
-import okio.Okio;
-
-public final class JConfiguration {
-
-   private static final String TAG = "Configuration";
-
-   private static final String PREFS_NAME = "config";
-   private static final String KEY_LAST_HASH = "lastHash";
-
-   private static WeakReference<JConfiguration> sInstance = new WeakReference<>(null);
-
-   private final Context mContext;
-   private final SharedPreferences mPrefs;
-   private final Resources mResources;
-
-   private JSONObject mConfigJson;
-   private String mConfigHash;
-   private String mConfigError;
-
-   private String mClientId;
-   private String mScope;
-   private Uri mRedirectUri;
-   private Uri mEndSessionRedirectUri;
-   private Uri mDiscoveryUri;
-   private Uri mAuthEndpointUri;
-   private Uri mTokenEndpointUri;
-   private Uri mEndSessionEndpoint;
-   private Uri mRegistrationEndpointUri;
-   private Uri mUserInfoEndpointUri;
-   private boolean mHttpsRequired;
-
-   public static JConfiguration getInstance(Context context) {
-      JConfiguration config = sInstance.get();
-      if (config == null) {
-         config = new JConfiguration(context);
-         sInstance = new WeakReference<JConfiguration>(config);
-      }
-
-      return config;
-   }
-
-   public JConfiguration(Context context) {
-      mContext = context;
-      mPrefs = context.getSharedPreferences(PREFS_NAME, Context.MODE_PRIVATE);
-      mResources = context.getResources();
-
-      try {
-         readConfiguration();
-      } catch (InvalidConfigurationException ex) {
-         mConfigError = ex.getMessage();
-      }
-   }
-
-   /**
-    * Indicates whether the configuration has changed from the last known valid state.
-    */
-   public boolean hasConfigurationChanged() {
-      String lastHash = getLastKnownConfigHash();
-      return !mConfigHash.equals(lastHash);
-   }
-
-   /**
-    * Indicates whether the current configuration is valid.
-    */
-   public boolean isValid() {
-      return mConfigError == null;
-   }
-
-   /**
-    * Returns a description of the configuration error, if the configuration is invalid.
-    */
-   @Nullable
-   public String getConfigurationError() {
-      return mConfigError;
-   }
-
-   /**
-    * Indicates that the current configuration should be accepted as the "last known valid"
-    * configuration.
-    */
-   public void acceptConfiguration() {
-      mPrefs.edit().putString(KEY_LAST_HASH, mConfigHash).apply();
-   }
-
-   @Nullable
-   public String getClientId() {
-      return mClientId;
-   }
-
-   @NonNull
-   public String getScope() {
-      return mScope;
-   }
-
-   @NonNull
-   public Uri getRedirectUri() {
-      return mRedirectUri;
-   }
-
-   @Nullable
-   public Uri getDiscoveryUri() {
-      return mDiscoveryUri;
-   }
-
-   @Nullable
-   public Uri getEndSessionRedirectUri() { return mEndSessionRedirectUri; }
-
-   @Nullable
-   public Uri getAuthEndpointUri() {
-      return mAuthEndpointUri;
-   }
-
-   @Nullable
-   public Uri getTokenEndpointUri() {
-      return mTokenEndpointUri;
-   }
-
-   @Nullable
-   public Uri getEndSessionEndpoint() {
-      return mEndSessionEndpoint;
-   }
-
-   @Nullable
-   public Uri getRegistrationEndpointUri() {
-      return mRegistrationEndpointUri;
-   }
-
-   @Nullable
-   public Uri getUserInfoEndpointUri() {
-      return mUserInfoEndpointUri;
-   }
-
-   public boolean isHttpsRequired() {
-      return mHttpsRequired;
-   }
-
-   public ConnectionBuilder getConnectionBuilder() {
-      if (isHttpsRequired()) {
-         return DefaultConnectionBuilder.INSTANCE;
-      }
-      return ConnectionBuilderForTesting.INSTANCE;
-   }
-
-   private String getLastKnownConfigHash() {
-      return mPrefs.getString(KEY_LAST_HASH, null);
-   }
-
-   private void readConfiguration() throws InvalidConfigurationException {
-      BufferedSource configSource =
-          Okio.buffer(Okio.source(mResources.openRawResource(R.raw.auth_config)));
-      Buffer configData = new Buffer();
-      try {
-         configSource.readAll(configData);
-         mConfigJson = new JSONObject(configData.readString(StandardCharsets.UTF_8));
-      } catch (IOException ex) {
-         throw new InvalidConfigurationException(
-             "Failed to read configuration: " + ex.getMessage());
-      } catch (JSONException ex) {
-         throw new InvalidConfigurationException(
-             "Unable to parse configuration: " + ex.getMessage());
-      }
-
-      mConfigHash = configData.sha256().base64();
-      mClientId = getConfigString("client_id");
-      mScope = getRequiredConfigString("authorization_scope");
-      mRedirectUri = getRequiredConfigUri("redirect_uri");
-      mEndSessionRedirectUri = getRequiredConfigUri("end_session_redirect_uri");
-
-      if (!isRedirectUriRegistered()) {
-         throw new InvalidConfigurationException(
-             "redirect_uri is not handled by any activity in this app! "
-                 + "Ensure that the appAuthRedirectScheme in your build.gradle file "
-                 + "is correctly configured, or that an appropriate intent filter "
-                 + "exists in your app manifest.");
-      }
-
-      if (getConfigString("discovery_uri") == null) {
-         mAuthEndpointUri = getRequiredConfigWebUri("authorization_endpoint_uri");
-
-         mTokenEndpointUri = getRequiredConfigWebUri("token_endpoint_uri");
-         mUserInfoEndpointUri = getRequiredConfigWebUri("user_info_endpoint_uri");
-         mEndSessionEndpoint = getRequiredConfigUri("end_session_endpoint");
-
-         if (mClientId == null) {
-            mRegistrationEndpointUri = getRequiredConfigWebUri("registration_endpoint_uri");
-         }
-      } else {
-         mDiscoveryUri = getRequiredConfigWebUri("discovery_uri");
-      }
-
-      mHttpsRequired = mConfigJson.optBoolean("https_required", true);
-   }
-
-   @Nullable
-   String getConfigString(String propName) {
-      String value = mConfigJson.optString(propName);
-      if (value == null) {
-         return null;
-      }
-
-      value = value.trim();
-      if (TextUtils.isEmpty(value)) {
-         return null;
-      }
-
-      return value;
-   }
-
-   @NonNull
-   private String getRequiredConfigString(String propName)
-       throws InvalidConfigurationException {
-      String value = getConfigString(propName);
-      if (value == null) {
-         throw new InvalidConfigurationException(
-             propName + " is required but not specified in the configuration");
-      }
-
-      return value;
-   }
-
-   @NonNull
-   Uri getRequiredConfigUri(String propName)
-       throws InvalidConfigurationException {
-      String uriStr = getRequiredConfigString(propName);
-      Uri uri;
-      try {
-         uri = Uri.parse(uriStr);
-      } catch (Throwable ex) {
-         throw new InvalidConfigurationException(propName + " could not be parsed", ex);
-      }
-
-      if (!uri.isHierarchical() || !uri.isAbsolute()) {
-         throw new InvalidConfigurationException(
-             propName + " must be hierarchical and absolute");
-      }
-
-      if (!TextUtils.isEmpty(uri.getEncodedUserInfo())) {
-         throw new InvalidConfigurationException(propName + " must not have user info");
-      }
-
-      if (!TextUtils.isEmpty(uri.getEncodedQuery())) {
-         throw new InvalidConfigurationException(propName + " must not have query parameters");
-      }
-
-      if (!TextUtils.isEmpty(uri.getEncodedFragment())) {
-         throw new InvalidConfigurationException(propName + " must not have a fragment");
-      }
-
-      return uri;
-   }
-
-   Uri getRequiredConfigWebUri(String propName)
-       throws InvalidConfigurationException {
-      Uri uri = getRequiredConfigUri(propName);
-      String scheme = uri.getScheme();
-      if (TextUtils.isEmpty(scheme) || !("http".equals(scheme) || "https".equals(scheme))) {
-         throw new InvalidConfigurationException(
-             propName + " must have an http or https scheme");
-      }
-
-      return uri;
-   }
-
-   private boolean isRedirectUriRegistered() {
-      // ensure that the redirect URI declared in the configuration is handled by some activity
-      // in the app, by querying the package manager speculatively
-      Intent redirectIntent = new Intent();
-      redirectIntent.setPackage(mContext.getPackageName());
-      redirectIntent.setAction(Intent.ACTION_VIEW);
-      redirectIntent.addCategory(Intent.CATEGORY_BROWSABLE);
-      redirectIntent.setData(mRedirectUri);
-
-      return !mContext.getPackageManager().queryIntentActivities(redirectIntent, 0).isEmpty();
-   }
-
-   public static final class InvalidConfigurationException extends Exception {
-      InvalidConfigurationException(String reason) {
-         super(reason);
-      }
-
-      InvalidConfigurationException(String reason, Throwable cause) {
-         super(reason, cause);
-      }
-   }
-}

app/src/com/jc/jcfw/appauth/JConfiguration.kt

@@ -0,0 +1,223 @@
+package com.jc.jcfw.appauth
+
+import android.content.Context
+import android.content.Intent
+import android.content.SharedPreferences
+import android.content.res.Resources
+import android.net.Uri
+import android.text.TextUtils
+import com.ctf.games.release.R
+import net.openid.appauth.connectivity.ConnectionBuilder
+import net.openid.appauth.connectivity.DefaultConnectionBuilder
+import okio.Buffer
+import okio.buffer
+import okio.source
+import org.json.JSONException
+import org.json.JSONObject
+import java.io.IOException
+import java.lang.ref.WeakReference
+import java.nio.charset.StandardCharsets
+
+class JConfiguration(private val mContext: Context) {
+  private val mPrefs: SharedPreferences
+  private val mResources: Resources
+  private var mConfigJson: JSONObject? = null
+  private var mConfigHash: String? = null
+
+  /**
+   * Returns a description of the configuration error, if the configuration is invalid.
+   */
+  var configurationError: String? = null
+  var clientId: String? = null
+    private set
+  private var mScope: String? = null
+  private var mRedirectUri: Uri? = null
+  var endSessionRedirectUri: Uri? = null
+    private set
+  var discoveryUri: Uri? = null
+    private set
+  var authEndpointUri: Uri? = null
+    private set
+  var tokenEndpointUri: Uri? = null
+    private set
+  var endSessionEndpoint: Uri? = null
+    private set
+  var registrationEndpointUri: Uri? = null
+    private set
+  var userInfoEndpointUri: Uri? = null
+    private set
+  var isHttpsRequired = false
+    private set
+
+  init {
+    mPrefs = mContext.getSharedPreferences(PREFS_NAME, Context.MODE_PRIVATE)
+    mResources = mContext.resources
+    try {
+      readConfiguration()
+    } catch (ex: InvalidConfigurationException) {
+      configurationError = ex.message
+    }
+  }
+
+  /**
+   * Indicates whether the configuration has changed from the last known valid state.
+   */
+  fun hasConfigurationChanged(): Boolean {
+    val lastHash = lastKnownConfigHash
+    return mConfigHash != lastHash
+  }
+
+  /**
+   * Indicates whether the current configuration is valid.
+   */
+  val isValid: Boolean
+    get() = configurationError == null
+
+  /**
+   * Indicates that the current configuration should be accepted as the "last known valid"
+   * configuration.
+   */
+  fun acceptConfiguration() {
+    mPrefs.edit().putString(KEY_LAST_HASH, mConfigHash).apply()
+  }
+
+  val scope: String
+    get() = mScope!!
+  val redirectUri: Uri
+    get() = mRedirectUri!!
+  val connectionBuilder: ConnectionBuilder
+    get() = DefaultConnectionBuilder.INSTANCE
+  private val lastKnownConfigHash: String?
+    private get() = mPrefs.getString(KEY_LAST_HASH, null)
+
+  @Throws(InvalidConfigurationException::class)
+  private fun readConfiguration() {
+    val configSource = mResources.openRawResource(R.raw.auth_config).source().buffer()
+    val configData = Buffer()
+    mConfigJson = try {
+      configSource.readAll(configData)
+      JSONObject(configData.readString(StandardCharsets.UTF_8))
+    } catch (ex: IOException) {
+      throw InvalidConfigurationException(
+        "Failed to read configuration: " + ex.message
+      )
+    } catch (ex: JSONException) {
+      throw InvalidConfigurationException(
+        "Unable to parse configuration: " + ex.message
+      )
+    }
+    mConfigHash = configData.sha256().base64()
+    clientId = getConfigString("client_id")
+    mScope = getRequiredConfigString("authorization_scope")
+    mRedirectUri = getRequiredConfigUri("redirect_uri")
+    endSessionRedirectUri = getRequiredConfigUri("end_session_redirect_uri")
+    if (!isRedirectUriRegistered) {
+      throw InvalidConfigurationException(
+        "redirect_uri is not handled by any activity in this app! "
+            + "Ensure that the appAuthRedirectScheme in your build.gradle file "
+            + "is correctly configured, or that an appropriate intent filter "
+            + "exists in your app manifest."
+      )
+    }
+    if (getConfigString("discovery_uri") == null) {
+      authEndpointUri = getRequiredConfigWebUri("authorization_endpoint_uri")
+      tokenEndpointUri = getRequiredConfigWebUri("token_endpoint_uri")
+      userInfoEndpointUri = getRequiredConfigWebUri("user_info_endpoint_uri")
+      endSessionEndpoint = getRequiredConfigUri("end_session_endpoint")
+      if (clientId == null) {
+        registrationEndpointUri = getRequiredConfigWebUri("registration_endpoint_uri")
+      }
+    } else {
+      discoveryUri = getRequiredConfigWebUri("discovery_uri")
+    }
+    isHttpsRequired = mConfigJson!!.optBoolean("https_required", true)
+  }
+
+  fun getConfigString(propName: String?): String? {
+    var value = mConfigJson!!.optString(propName) ?: return null
+    value = value.trim { it <= ' ' }
+    return if (TextUtils.isEmpty(value)) {
+      null
+    } else value
+  }
+
+  @Throws(InvalidConfigurationException::class)
+  private fun getRequiredConfigString(propName: String): String {
+    return getConfigString(propName)
+      ?: throw InvalidConfigurationException(
+        "$propName is required but not specified in the configuration"
+      )
+  }
+
+  @Throws(InvalidConfigurationException::class)
+  fun getRequiredConfigUri(propName: String): Uri {
+    val uriStr = getRequiredConfigString(propName)
+    val uri: Uri
+    uri = try {
+      Uri.parse(uriStr)
+    } catch (ex: Throwable) {
+      throw InvalidConfigurationException("$propName could not be parsed", ex)
+    }
+    if (!uri.isHierarchical || !uri.isAbsolute) {
+      throw InvalidConfigurationException(
+        "$propName must be hierarchical and absolute"
+      )
+    }
+    if (!TextUtils.isEmpty(uri.encodedUserInfo)) {
+      throw InvalidConfigurationException("$propName must not have user info")
+    }
+    if (!TextUtils.isEmpty(uri.encodedQuery)) {
+      throw InvalidConfigurationException("$propName must not have query parameters")
+    }
+    if (!TextUtils.isEmpty(uri.encodedFragment)) {
+      throw InvalidConfigurationException("$propName must not have a fragment")
+    }
+    return uri
+  }
+
+  @Throws(InvalidConfigurationException::class)
+  fun getRequiredConfigWebUri(propName: String): Uri {
+    val uri = getRequiredConfigUri(propName)
+    val scheme = uri.scheme
+    if (TextUtils.isEmpty(scheme) || !("http" == scheme || "https" == scheme)) {
+      throw InvalidConfigurationException(
+        "$propName must have an http or https scheme"
+      )
+    }
+    return uri
+  }
+
+  // ensure that the redirect URI declared in the configuration is handled by some activity
+  // in the app, by querying the package manager speculatively
+  private val isRedirectUriRegistered: Boolean
+    private get() {
+      // ensure that the redirect URI declared in the configuration is handled by some activity
+      // in the app, by querying the package manager speculatively
+      val redirectIntent = Intent()
+      redirectIntent.setPackage(mContext.packageName)
+      redirectIntent.action = Intent.ACTION_VIEW
+      redirectIntent.addCategory(Intent.CATEGORY_BROWSABLE)
+      redirectIntent.data = mRedirectUri
+      return !mContext.packageManager.queryIntentActivities(redirectIntent, 0).isEmpty()
+    }
+
+  class InvalidConfigurationException : Exception {
+    internal constructor(reason: String?) : super(reason) {}
+    internal constructor(reason: String?, cause: Throwable?) : super(reason, cause) {}
+  }
+
+  companion object {
+    private const val TAG = "Configuration"
+    private const val PREFS_NAME = "config"
+    private const val KEY_LAST_HASH = "lastHash"
+    private var sInstance = WeakReference<JConfiguration?>(null)
+    fun getInstance(context: Context): JConfiguration {
+      var config = sInstance.get()
+      if (config == null) {
+        config = JConfiguration(context)
+        sInstance = WeakReference(config)
+      }
+      return config
+    }
+  }
+}

app/src/com/jc/jcfw/security/BiometricHelper.java

@@ -1,61 +0,0 @@
-package com.jc.jcfw.security;
-
-import static androidx.biometric.BiometricManager.Authenticators.BIOMETRIC_STRONG;
-import static androidx.biometric.BiometricManager.Authenticators.DEVICE_CREDENTIAL;
-
-import android.content.Context;
-import android.util.Log;
-
-import androidx.annotation.NonNull;
-import androidx.biometric.BiometricPrompt;
-import androidx.core.content.ContextCompat;
-import androidx.fragment.app.FragmentActivity;
-
-import com.ctf.games.release.R;
-
-import java.util.concurrent.Executor;
-import java.util.function.Consumer;
-
-public class BiometricHelper {
-
-  public static final int ERROR_BIOMETRIC_FAIL = 100;
-  public static final int ERROR_BIOMETRIC_NO_CIPHER = 101;
-  private static final String TAG = BiometricHelper.class.getSimpleName();
-  public static BiometricPrompt.PromptInfo createPromptInfo(Context context) {
-    BiometricPrompt.PromptInfo promptInfo = new BiometricPrompt.PromptInfo.Builder()
-        .setTitle(context.getString(R.string.prompt_info_title)) // e.g. "Sign in"
-        .setSubtitle(context.getString(R.string.prompt_info_subtitle)) // e.g. "Biometric for My App"
-        .setDescription(context.getString(R.string.prompt_info_description)) // e.g. "Confirm biometric to continue"
-        .setConfirmationRequired(false)
-        .setAllowedAuthenticators(BIOMETRIC_STRONG | DEVICE_CREDENTIAL)
-//                 .setDeviceCredentialAllowed(true) // Allow PIN/pattern/password authentication.
-        // Also note that setDeviceCredentialAllowed and setNegativeButtonText are
-        // incompatible so that if you uncomment one you must comment out the other
-        .build();
-    return promptInfo;
-  }
-
-  public static BiometricPrompt createBiometricPrompt(FragmentActivity activity, Consumer<BiometricResult> func) {
-    Executor executor = ContextCompat.getMainExecutor(activity.getApplicationContext());
-    return new BiometricPrompt(activity, executor, new BiometricPrompt.AuthenticationCallback() {
-      @Override
-      public void onAuthenticationError(int errcode, @NonNull CharSequence errString) {
-        super.onAuthenticationError(errcode, errString);
-        Log.i(TAG, "Authentication error: " + errcode +" | "+ errString);
-        func.accept(new BiometricResult(errcode, (String) errString));
-      }
-      @Override
-      public void onAuthenticationFailed() {
-        super.onAuthenticationFailed();
-        Log.i(TAG, "Authentication failed!");
-        func.accept(new BiometricResult(ERROR_BIOMETRIC_FAIL, "Authentication failed"));
-      }
-      @Override
-      public void onAuthenticationSucceeded(@NonNull BiometricPrompt.AuthenticationResult result) {
-        super.onAuthenticationSucceeded(result);
-        Log.i(TAG, "Authentication succeeded!");
-        func.accept(new BiometricResult(result.getCryptoObject().getCipher()));
-      }
-    });
-  }
-}

app/src/com/jc/jcfw/security/BiometricHelper.kt

@@ -0,0 +1,54 @@
+package com.jc.jcfw.security
+
+import android.content.Context
+import android.util.Log
+import androidx.biometric.BiometricManager
+import androidx.biometric.BiometricPrompt
+import androidx.biometric.BiometricPrompt.PromptInfo
+import androidx.core.content.ContextCompat
+import androidx.fragment.app.FragmentActivity
+import com.ctf.games.release.R
+import java.util.function.Consumer
+
+object BiometricHelper {
+  const val ERROR_BIOMETRIC_FAIL = 100
+  const val ERROR_BIOMETRIC_NO_CIPHER = 101
+  private val TAG = BiometricHelper::class.java.simpleName
+  fun createPromptInfo(context: Context): PromptInfo {
+    return PromptInfo.Builder()
+      .setTitle(context.getString(R.string.prompt_info_title)) // e.g. "Sign in"
+      .setSubtitle(context.getString(R.string.prompt_info_subtitle)) // e.g. "Biometric for My App"
+      .setDescription(context.getString(R.string.prompt_info_description)) // e.g. "Confirm biometric to continue"
+      .setConfirmationRequired(false)
+      .setAllowedAuthenticators(BiometricManager.Authenticators.BIOMETRIC_STRONG or BiometricManager.Authenticators.DEVICE_CREDENTIAL) //                 .setDeviceCredentialAllowed(true) // Allow PIN/pattern/password authentication.
+      // Also note that setDeviceCredentialAllowed and setNegativeButtonText are
+      // incompatible so that if you uncomment one you must comment out the other
+      .build()
+  }
+
+  fun createBiometricPrompt(
+    activity: FragmentActivity,
+    func: Consumer<BiometricResult>
+  ): BiometricPrompt {
+    val executor = ContextCompat.getMainExecutor(activity.applicationContext)
+    return BiometricPrompt(activity, executor, object : BiometricPrompt.AuthenticationCallback() {
+      override fun onAuthenticationError(errcode: Int, errString: CharSequence) {
+        super.onAuthenticationError(errcode, errString)
+        Log.i(TAG, "Authentication error: $errcode | $errString")
+        func.accept(BiometricResult(errcode, errString as String))
+      }
+
+      override fun onAuthenticationFailed() {
+        super.onAuthenticationFailed()
+        Log.i(TAG, "Authentication failed!")
+        func.accept(BiometricResult(ERROR_BIOMETRIC_FAIL, "Authentication failed"))
+      }
+
+      override fun onAuthenticationSucceeded(result: BiometricPrompt.AuthenticationResult) {
+        super.onAuthenticationSucceeded(result)
+        Log.i(TAG, "Authentication succeeded!")
+        func.accept(BiometricResult(result.cryptoObject!!.cipher))
+      }
+    })
+  }
+}

app/src/com/jc/jcfw/security/BiometricResult.java

@@ -1,61 +0,0 @@
-package com.jc.jcfw.security;
-
-import androidx.annotation.Nullable;
-
-import javax.crypto.Cipher;
-
-public class BiometricResult {
-  private Cipher cipher;
-  private boolean error;
-  private int errcode;
-  private String errmsg;
-
-  public BiometricResult(Cipher cipher) {
-    if (null != cipher) {
-      this.cipher = cipher;
-      this.error = false;
-    } else {
-      this.error = true;
-      this.errcode = 101;
-      this.errmsg = "cipher is null";
-    }
-  }
-
-  public BiometricResult(int errcode, String errmsg) {
-    this.error = true;
-    this.errcode = errcode;
-    this.errmsg = errmsg;
-  }
-  @Nullable
-  public Cipher getCipher() {
-    return cipher;
-  }
-
-  public void setCipher(Cipher cipher) {
-    this.cipher = cipher;
-  }
-
-  public boolean isError() {
-    return error;
-  }
-
-  public void setError(boolean error) {
-    this.error = error;
-  }
-
-  public int getErrcode() {
-    return errcode;
-  }
-
-  public void setErrcode(int errcode) {
-    this.errcode = errcode;
-  }
-
-  public String getErrmsg() {
-    return errmsg;
-  }
-
-  public void setErrmsg(String errmsg) {
-    this.errmsg = errmsg;
-  }
-}

app/src/com/jc/jcfw/security/BiometricResult.kt

@@ -0,0 +1,27 @@
+package com.jc.jcfw.security
+
+import javax.crypto.Cipher
+
+class BiometricResult {
+  var cipher: Cipher? = null
+  var isError = false
+  var errcode = 0
+  var errmsg: String? = null
+
+  constructor(cipher: Cipher?) {
+    if (null != cipher) {
+      this.cipher = cipher
+      isError = false
+    } else {
+      isError = true
+      errcode = 101
+      errmsg = "cipher is null"
+    }
+  }
+
+  constructor(errcode: Int, errmsg: String?) {
+    isError = true
+    this.errcode = errcode
+    this.errmsg = errmsg
+  }
+}

app/src/com/jc/jcfw/security/CryptographyManager.kt

@@ -1,27 +1,27 @@
-package com.jc.jcfw.security;
+package com.jc.jcfw.security
 
-import javax.crypto.Cipher;
+import javax.crypto.Cipher
 
-public interface CryptographyManager {
+interface CryptographyManager {
   /**
    * This method first gets or generates an instance of SecretKey and then initializes the Cipher
    * with the key. The secret key uses [ENCRYPT_MODE][Cipher.ENCRYPT_MODE] is used.
    */
-  Cipher getInitializedCipherForEncryption(String keyName);
+  fun getInitializedCipherForEncryption(keyName: String?): Cipher?
 
   /**
    * This method first gets or generates an instance of SecretKey and then initializes the Cipher
    * with the key. The secret key uses [DECRYPT_MODE][Cipher.DECRYPT_MODE] is used.
    */
-  Cipher getInitializedCipherForDecryption(String keyName, byte[] initializationVector);
+  fun getInitializedCipherForDecryption(keyName: String?, initializationVector: ByteArray?): Cipher?
 
   /**
    * The Cipher created with [getInitializedCipherForEncryption] is used here
    */
-  EncryptedData encryptData(String plaintext, Cipher cipher);
+  fun encryptData(plaintext: String?, cipher: Cipher?): EncryptedData?
 
   /**
    * The Cipher created with [getInitializedCipherForDecryption] is used here
    */
-  String decryptData(byte[] ciphertext, Cipher cipher);
+  fun decryptData(ciphertext: ByteArray?, cipher: Cipher?): String?
 }

app/src/com/jc/jcfw/security/CryptographyManagerImpl.java

@@ -1,101 +0,0 @@
-package com.jc.jcfw.security;
-
-import static android.security.keystore.KeyProperties.BLOCK_MODE_CBC;
-import static android.security.keystore.KeyProperties.ENCRYPTION_PADDING_PKCS7;
-
-import android.security.keystore.KeyGenParameterSpec;
-import android.security.keystore.KeyProperties;
-import android.util.Log;
-
-import java.nio.charset.Charset;
-import java.nio.charset.StandardCharsets;
-import java.security.KeyPair;
-import java.security.KeyPairGenerator;
-import java.security.KeyStore;
-
-import javax.crypto.Cipher;
-import javax.crypto.KeyGenerator;
-import javax.crypto.SecretKey;
-import javax.crypto.spec.IvParameterSpec;
-import javax.crypto.spec.SecretKeySpec;
-
-public class CryptographyManagerImpl implements CryptographyManager {
-
-  @Override
-  public Cipher getInitializedCipherForEncryption(String keyName) {
-    Cipher cipher;
-    try {
-      cipher = getCipher();
-      SecretKey secretKey = getOrCreateSecretKey(keyName);
-      cipher.init(Cipher.ENCRYPT_MODE, secretKey);
-    } catch (Exception e) {
-      throw new RuntimeException("Failed to initialize Cipher for encryption", e);
-    }
-    return cipher;
-  }
-
-  @Override
-  public Cipher getInitializedCipherForDecryption(String keyName, byte[] initializationVector) {
-    Cipher cipher;
-    try {
-      cipher = getCipher();
-      SecretKey secretKey = getOrCreateSecretKey(keyName);
-      cipher.init(Cipher.DECRYPT_MODE, secretKey, new IvParameterSpec(initializationVector));
-    } catch (Exception e) {
-      throw new RuntimeException("Failed to initialize Cipher for decryption", e);
-    }
-    return cipher;
-  }
-
-  @Override
-  public EncryptedData encryptData(String plaintext, Cipher cipher) {
-    try {
-      byte[] ciphertext = cipher.doFinal(plaintext.getBytes(Charset.defaultCharset()));
-      return new EncryptedData(ciphertext, cipher.getIV());
-    } catch (Exception e) {
-      throw new RuntimeException("Failed to encrypt data", e);
-    }
-  }
-
-  @Override
-  public String decryptData(byte[] ciphertext, Cipher cipher) {
-    try {
-      byte[] plaintext = cipher.doFinal(ciphertext);
-      return new String(plaintext, StandardCharsets.UTF_8);
-    } catch (Exception e) {
-      throw new RuntimeException("Failed to encrypt data", e);
-    }
-  }
-
-  private Cipher getCipher() throws Exception {
-    return Cipher.getInstance(KeyProperties.KEY_ALGORITHM_AES + "/"
-        + BLOCK_MODE_CBC + "/"
-        + ENCRYPTION_PADDING_PKCS7);
-  }
-
-  private SecretKey getOrCreateSecretKey(String keyName) throws Exception {
-    String ANDROID_KEYSTORE = "AndroidKeyStore";
-    KeyStore keyStore = KeyStore.getInstance(ANDROID_KEYSTORE);
-    keyStore.load(null); // Keystore must be loaded before it can be accessed
-    SecretKey existingKey = (SecretKey) keyStore.getKey(keyName, null);
-    if (existingKey != null) {
-      return existingKey;
-    }
-
-    // if you reach here, then a new SecretKey must be generated for that keyName
-    KeyGenParameterSpec.Builder paramsBuilder = new KeyGenParameterSpec.Builder(keyName,
-        KeyProperties.PURPOSE_ENCRYPT | KeyProperties.PURPOSE_DECRYPT);
-    paramsBuilder.setBlockModes(BLOCK_MODE_CBC);
-    paramsBuilder.setEncryptionPaddings(ENCRYPTION_PADDING_PKCS7);
-    int KEY_SIZE = 256;
-    paramsBuilder.setKeySize(KEY_SIZE);
-    paramsBuilder.setUserAuthenticationRequired(false);
-    paramsBuilder.setUserAuthenticationValidityDurationSeconds(30);
-
-    KeyGenParameterSpec keyGenParams = paramsBuilder.build();
-    KeyGenerator keyGenerator = KeyGenerator.getInstance(KeyProperties.KEY_ALGORITHM_AES,
-        ANDROID_KEYSTORE);
-    keyGenerator.init(keyGenParams);
-    return keyGenerator.generateKey();
-  }
-}

app/src/com/jc/jcfw/security/CryptographyManagerImpl.kt

@@ -0,0 +1,96 @@
+package com.jc.jcfw.security
+
+import android.security.keystore.KeyGenParameterSpec
+import android.security.keystore.KeyProperties
+import java.nio.charset.Charset
+import java.nio.charset.StandardCharsets
+import java.security.KeyStore
+import javax.crypto.Cipher
+import javax.crypto.KeyGenerator
+import javax.crypto.SecretKey
+import javax.crypto.spec.IvParameterSpec
+
+class CryptographyManagerImpl : CryptographyManager {
+  override fun getInitializedCipherForEncryption(keyName: String?): Cipher? {
+    val cipher: Cipher
+    try {
+      cipher = this.cipher
+      val secretKey = getOrCreateSecretKey(keyName)
+      cipher.init(Cipher.ENCRYPT_MODE, secretKey)
+    } catch (e: Exception) {
+      throw RuntimeException("Failed to initialize Cipher for encryption", e)
+    }
+    return cipher
+  }
+
+  override fun getInitializedCipherForDecryption(
+    keyName: String?,
+    initializationVector: ByteArray?
+  ): Cipher? {
+    val cipher: Cipher
+    try {
+      cipher = this.cipher
+      val secretKey = getOrCreateSecretKey(keyName)
+      cipher.init(Cipher.DECRYPT_MODE, secretKey, IvParameterSpec(initializationVector))
+    } catch (e: Exception) {
+      throw RuntimeException("Failed to initialize Cipher for decryption", e)
+    }
+    return cipher
+  }
+
+  override fun encryptData(plaintext: String?, cipher: Cipher?): EncryptedData? {
+    return try {
+      val ciphertext = cipher!!.doFinal(plaintext!!.toByteArray(Charset.defaultCharset()))
+      EncryptedData(ciphertext, cipher.iv)
+    } catch (e: Exception) {
+      throw RuntimeException("Failed to encrypt data", e)
+    }
+  }
+
+  override fun decryptData(ciphertext: ByteArray?, cipher: Cipher?): String? {
+    return try {
+      val plaintext = cipher!!.doFinal(ciphertext)
+      String(plaintext, StandardCharsets.UTF_8)
+    } catch (e: Exception) {
+      throw RuntimeException("Failed to encrypt data", e)
+    }
+  }
+
+  @get:Throws(Exception::class)
+  private val cipher: Cipher
+    private get() = Cipher.getInstance(
+      KeyProperties.KEY_ALGORITHM_AES + "/"
+          + KeyProperties.BLOCK_MODE_CBC + "/"
+          + KeyProperties.ENCRYPTION_PADDING_PKCS7
+    )
+
+  @Throws(Exception::class)
+  private fun getOrCreateSecretKey(keyName: String?): SecretKey {
+    val ANDROID_KEYSTORE = "AndroidKeyStore"
+    val keyStore = KeyStore.getInstance(ANDROID_KEYSTORE)
+    keyStore.load(null) // Keystore must be loaded before it can be accessed
+    val existingKey = keyStore.getKey(keyName, null) as SecretKey
+    if (existingKey != null) {
+      return existingKey
+    }
+
+    // if you reach here, then a new SecretKey must be generated for that keyName
+    val paramsBuilder = KeyGenParameterSpec.Builder(
+      keyName!!,
+      KeyProperties.PURPOSE_ENCRYPT or KeyProperties.PURPOSE_DECRYPT
+    )
+    paramsBuilder.setBlockModes(KeyProperties.BLOCK_MODE_CBC)
+    paramsBuilder.setEncryptionPaddings(KeyProperties.ENCRYPTION_PADDING_PKCS7)
+    val KEY_SIZE = 256
+    paramsBuilder.setKeySize(KEY_SIZE)
+    paramsBuilder.setUserAuthenticationRequired(false)
+    paramsBuilder.setUserAuthenticationValidityDurationSeconds(30)
+    val keyGenParams = paramsBuilder.build()
+    val keyGenerator = KeyGenerator.getInstance(
+      KeyProperties.KEY_ALGORITHM_AES,
+      ANDROID_KEYSTORE
+    )
+    keyGenerator.init(keyGenParams)
+    return keyGenerator.generateKey()
+  }
+}

app/src/com/jc/jcfw/security/EncryptedData.java

@@ -1,19 +0,0 @@
-package com.jc.jcfw.security;
-
-public class EncryptedData {
-  private final byte[] ciphertext;
-  private final byte[] initializationVector;
-
-  public EncryptedData(byte[] ciphertext, byte[] initializationVector) {
-    this.ciphertext = ciphertext;
-    this.initializationVector = initializationVector;
-  }
-
-  public byte[] getCiphertext() {
-    return ciphertext;
-  }
-
-  public byte[] getInitializationVector() {
-    return initializationVector;
-  }
-}

app/src/com/jc/jcfw/security/EncryptedData.kt

@@ -0,0 +1,3 @@
+package com.jc.jcfw.security
+
+class EncryptedData(val ciphertext: ByteArray, val initializationVector: ByteArray)