Add fingerprint support

app/src/main/java/me/impy/aegis/AuthActivity.java

@@ -1,38 +1,84 @@
 package me.impy.aegis;
 
+import android.Manifest;
+import android.content.Context;
 import android.content.Intent;
+import android.content.pm.PackageManager;
+import android.hardware.fingerprint.FingerprintManager;
+import android.os.Build;
+import android.support.v4.app.ActivityCompat;
 import android.support.v7.app.AppCompatActivity;
 import android.os.Bundle;
-import android.text.Editable;
 import android.view.View;
 import android.widget.Button;
 import android.widget.EditText;
+import android.widget.ImageView;
+import android.widget.LinearLayout;
+import android.widget.RadioButton;
+import android.widget.TextView;
 
 import java.lang.reflect.UndeclaredThrowableException;
 
+import javax.crypto.BadPaddingException;
 import javax.crypto.Cipher;
+import javax.crypto.IllegalBlockSizeException;
 import javax.crypto.SecretKey;
 
 import me.impy.aegis.crypto.CryptoUtils;
+import me.impy.aegis.crypto.KeyStoreHandle;
 import me.impy.aegis.crypto.MasterKey;
+import me.impy.aegis.crypto.slots.FingerprintSlot;
 import me.impy.aegis.crypto.slots.PasswordSlot;
 import me.impy.aegis.crypto.slots.Slot;
 import me.impy.aegis.crypto.slots.SlotCollection;
+import me.impy.aegis.finger.FingerprintUiHelper;
+import me.impy.aegis.helpers.AuthHelper;
 
-public class AuthActivity extends AppCompatActivity {
+public class AuthActivity extends AppCompatActivity implements FingerprintUiHelper.Callback {
     public static final int RESULT_OK = 0;
     public static final int RESULT_EXCEPTION = 1;
 
     private EditText textPassword;
 
+    private SlotCollection slots;
+    private LinearLayout boxFingerprint;
+    private ImageView imgFingerprint;
+    private TextView textFingerprint;
+    private FingerprintUiHelper fingerHelper;
+    private Cipher fingerCipher;
+
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_auth);
         textPassword = (EditText) findViewById(R.id.text_password);
+        boxFingerprint = (LinearLayout) findViewById(R.id.box_fingerprint);
+        imgFingerprint = (ImageView) findViewById(R.id.img_fingerprint);
+        textFingerprint = (TextView) findViewById(R.id.text_fingerprint);
 
         Intent intent = getIntent();
-        final SlotCollection slots = (SlotCollection) intent.getSerializableExtra("slots");
+        slots = (SlotCollection) intent.getSerializableExtra("slots");
+
+        // only show the fingerprint controls if the api version is new enough, permission is granted, a scanner is found and a fingerprint slot is found
+        Context context = getApplicationContext();
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
+            FingerprintManager manager = (FingerprintManager) context.getSystemService(Context.FINGERPRINT_SERVICE);
+            if (ActivityCompat.checkSelfPermission(context, Manifest.permission.USE_FINGERPRINT) == PackageManager.PERMISSION_GRANTED && manager.isHardwareDetected()) {
+                if (slots.has(FingerprintSlot.class)) {
+                    try {
+                        KeyStoreHandle handle = new KeyStoreHandle();
+                        if (handle.keyExists()) {
+                            SecretKey key = handle.getKey();
+                            fingerCipher = Slot.createCipher(key, Cipher.DECRYPT_MODE);
+                            fingerHelper = new FingerprintUiHelper(manager, imgFingerprint, textFingerprint, this);
+                            boxFingerprint.setVisibility(View.VISIBLE);
+                        }
+                    } catch (Exception e) {
+                        throw new UndeclaredThrowableException(e);
+                    }
+                }
+            }
+        }
 
         Button button = (Button) findViewById(R.id.button_decrypt);
         button.setOnClickListener(new View.OnClickListener() {
@@ -42,11 +88,13 @@ public class AuthActivity extends AppCompatActivity {
                 try {
                     if (slots.has(PasswordSlot.class)) {
                         PasswordSlot slot = slots.find(PasswordSlot.class);
-                        char[] password = getPassword(true);
+                        char[] password = AuthHelper.getPassword(textPassword, true);
                         SecretKey key = slot.deriveKey(password);
                         CryptoUtils.zero(password);
                         Cipher cipher = Slot.createCipher(key, Cipher.DECRYPT_MODE);
                         masterKey = MasterKey.decryptSlot(slot, cipher);
+                    } else {
+                        throw new RuntimeException();
                     }
                 } catch (Exception e) {
                     // TODO: feedback
@@ -54,31 +102,57 @@ public class AuthActivity extends AppCompatActivity {
                 }
 
                 // send the master key back to the main activity
-                Intent result = new Intent();
-                result.putExtra("key", masterKey);
-                setResult(RESULT_OK, result);
-                finish();
+                setKey(masterKey);
             }
         });
     }
 
+    private void setKey(MasterKey key) {
+        // send the master key back to the main activity
+        Intent result = new Intent();
+        result.putExtra("key", key);
+        setResult(RESULT_OK, result);
+        finish();
+    }
+
     @Override
     public void onBackPressed() {
         // ignore back button presses
     }
 
-    private char[] getPassword(boolean clear) {
-        char[] password = getEditTextChars(textPassword);
-        if (clear) {
-            textPassword.getText().clear();
+    @Override
+    public void onResume() {
+        super.onResume();
+
+        if (fingerHelper != null) {
+            fingerHelper.startListening(new FingerprintManager.CryptoObject(fingerCipher));
+        }
+    }
+
+    @Override
+    public void onPause() {
+        super.onPause();
+
+        if (fingerHelper != null) {
+            fingerHelper.stopListening();
         }
-        return password;
     }
 
-    private static char[] getEditTextChars(EditText text) {
-        Editable editable = text.getText();
-        char[] chars = new char[editable.length()];
-        editable.getChars(0, editable.length(), chars, 0);
-        return chars;
+    @Override
+    public void onAuthenticated() {
+        MasterKey key;
+        FingerprintSlot slot = slots.find(FingerprintSlot.class);
+        try {
+            key = new MasterKey(slot.getKey(fingerCipher));
+        } catch (Exception e) {
+            throw new UndeclaredThrowableException(e);
+        }
+
+        setKey(key);
+    }
+
+    @Override
+    public void onError() {
+
     }
 }

app/src/main/java/me/impy/aegis/CustomAuthenticatedSlide.java

@@ -1,42 +1,57 @@
 package me.impy.aegis;
 
+import android.content.Context;
 import android.content.Intent;
+import android.hardware.fingerprint.FingerprintManager;
 import android.os.Bundle;
 import android.support.design.widget.Snackbar;
 import android.support.v4.app.Fragment;
-import android.text.Editable;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
 import android.widget.EditText;
+import android.widget.ImageView;
+import android.widget.LinearLayout;
+import android.widget.TextView;
 
 import com.github.paolorotolo.appintro.ISlidePolicy;
 import com.github.paolorotolo.appintro.ISlideSelectionListener;
 
-import java.security.InvalidKeyException;
-import java.security.NoSuchAlgorithmException;
-import java.security.spec.InvalidKeySpecException;
-import java.util.Arrays;
+import java.lang.reflect.UndeclaredThrowableException;
 
 import javax.crypto.Cipher;
-import javax.crypto.NoSuchPaddingException;
 import javax.crypto.SecretKey;
 
 import me.impy.aegis.crypto.CryptoUtils;
+import me.impy.aegis.crypto.KeyStoreHandle;
+import me.impy.aegis.crypto.slots.FingerprintSlot;
 import me.impy.aegis.crypto.slots.PasswordSlot;
 import me.impy.aegis.crypto.slots.Slot;
+import me.impy.aegis.finger.FingerprintUiHelper;
+import me.impy.aegis.helpers.AuthHelper;
 
-public class CustomAuthenticatedSlide extends Fragment implements ISlidePolicy, ISlideSelectionListener {
+public class CustomAuthenticatedSlide extends Fragment implements FingerprintUiHelper.Callback, ISlidePolicy, ISlideSelectionListener {
     private int cryptType;
     private EditText textPassword;
     private EditText textPasswordConfirm;
     private int bgColor;
 
+    private LinearLayout boxFingerprint;
+    private ImageView imgFingerprint;
+    private TextView textFingerprint;
+    private FingerprintUiHelper fingerHelper;
+    private KeyStoreHandle storeHandle;
+    private Cipher fingerCipher;
+    private boolean fingerAuthenticated;
+
     @Override
     public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
         final View view = inflater.inflate(R.layout.fragment_authenticated_slide, container, false);
         textPassword = (EditText) view.findViewById(R.id.text_password);
         textPasswordConfirm = (EditText) view.findViewById(R.id.text_password_confirm);
+        boxFingerprint = (LinearLayout) view.findViewById(R.id.box_fingerprint);
+        imgFingerprint = (ImageView) view.findViewById(R.id.img_fingerprint);
+        textFingerprint = (TextView) view.findViewById(R.id.text_fingerprint);
         view.findViewById(R.id.main).setBackgroundColor(bgColor);
         return view;
     }
@@ -50,55 +65,75 @@ public class CustomAuthenticatedSlide extends Fragment implements ISlidePolicy,
         return cryptType;
     }
 
-    public Cipher getCipher(PasswordSlot slot, int mode)
-            throws InvalidKeySpecException, NoSuchAlgorithmException,
-            InvalidKeyException, NoSuchPaddingException {
-        char[] password = getPassword(true);
-        byte[] salt = CryptoUtils.generateSalt();
-        SecretKey key = slot.deriveKey(password, salt, CryptoUtils.CRYPTO_SCRYPT_N, CryptoUtils.CRYPTO_SCRYPT_r, CryptoUtils.CRYPTO_SCRYPT_p);
-        CryptoUtils.zero(password);
-
-        return Slot.createCipher(key, mode);
-    }
-
-    private char[] getPassword(boolean clear) {
-        char[] password = getEditTextChars(textPassword);
-        if (clear) {
-            textPassword.getText().clear();
+    public Cipher getCipher(Slot slot) throws Exception {
+        if (slot instanceof PasswordSlot) {
+            char[] password = AuthHelper.getPassword(textPassword, true);
+            byte[] salt = CryptoUtils.generateSalt();
+            SecretKey key = ((PasswordSlot)slot).deriveKey(password, salt, CryptoUtils.CRYPTO_SCRYPT_N, CryptoUtils.CRYPTO_SCRYPT_r, CryptoUtils.CRYPTO_SCRYPT_p);
+            CryptoUtils.zero(password);
+            return Slot.createCipher(key, Cipher.ENCRYPT_MODE);
+        } else if (slot instanceof FingerprintSlot) {
+            return fingerCipher;
+        } else {
+            throw new RuntimeException();
         }
-        return password;
     }
 
-    private static char[] getEditTextChars(EditText text) {
-        Editable editable = text.getText();
-        char[] chars = new char[editable.length()];
-        editable.getChars(0, editable.length(), chars, 0);
-        return chars;
+    public void setBgColor(int color) {
+        bgColor = color;
     }
 
     @Override
     public void onSlideSelected() {
         Intent intent = getActivity().getIntent();
-        cryptType = intent.getIntExtra("cryptType", 1337);
+        cryptType = intent.getIntExtra("cryptType", CustomAuthenticationSlide.CRYPT_TYPE_INVALID);
 
         switch(cryptType) {
             case CustomAuthenticationSlide.CRYPT_TYPE_NONE:
-                break;
             case CustomAuthenticationSlide.CRYPT_TYPE_PASS:
                 break;
             case CustomAuthenticationSlide.CRYPT_TYPE_FINGER:
+                boxFingerprint.setVisibility(View.VISIBLE);
+
+                SecretKey key;
+                try {
+                    if (storeHandle == null) {
+                        storeHandle = new KeyStoreHandle();
+                    }
+                    // TODO: consider regenerating the key if it exists
+                    if (!storeHandle.keyExists()) {
+                        key = storeHandle.generateKey(true);
+                    } else {
+                        key = storeHandle.getKey();
+                    }
+                } catch (Exception e) {
+                    throw new UndeclaredThrowableException(e);
+                }
+
+                if (fingerHelper == null) {
+                    FingerprintManager fingerManager = (FingerprintManager) getContext().getSystemService(Context.FINGERPRINT_SERVICE);
+                    fingerHelper = new FingerprintUiHelper(fingerManager, imgFingerprint, textFingerprint, this);
+                }
+
+                try {
+                    fingerCipher = Slot.createCipher(key, Cipher.ENCRYPT_MODE);
+                } catch (Exception e) {
+                    throw new UndeclaredThrowableException(e);
+                }
+                fingerHelper.startListening(new FingerprintManager.CryptoObject(fingerCipher));
                 break;
             default:
                 throw new RuntimeException();
         }
     }
 
-    public void setBgColor(int color) {
-        bgColor = color;
-    }
-
     @Override
     public void onSlideDeselected() {
+        if (fingerHelper != null) {
+            fingerAuthenticated = false;
+            boxFingerprint.setVisibility(View.INVISIBLE);
+            fingerHelper.stopListening();
+        }
     }
 
     @Override
@@ -106,15 +141,13 @@ public class CustomAuthenticatedSlide extends Fragment implements ISlidePolicy,
         switch(cryptType) {
             case CustomAuthenticationSlide.CRYPT_TYPE_NONE:
                 return true;
-            case CustomAuthenticationSlide.CRYPT_TYPE_PASS:
-                char[] password = getEditTextChars(textPassword);
-                char[] passwordConfirm = getEditTextChars(textPasswordConfirm);
-                boolean equal = password.length != 0 && Arrays.equals(password, passwordConfirm);
-                CryptoUtils.zero(password);
-                CryptoUtils.zero(passwordConfirm);
-                return equal;
             case CustomAuthenticationSlide.CRYPT_TYPE_FINGER:
-                return false;
+                if (!fingerAuthenticated) {
+                    return false;
+                }
+                // intentional fallthrough
+            case CustomAuthenticationSlide.CRYPT_TYPE_PASS:
+                return AuthHelper.arePasswordsEqual(textPassword, textPasswordConfirm);
             default:
                 throw new RuntimeException();
         }
@@ -122,10 +155,29 @@ public class CustomAuthenticatedSlide extends Fragment implements ISlidePolicy,
 
     @Override
     public void onUserIllegallyRequestedNextPage() {
+        String message;
+        if (!AuthHelper.arePasswordsEqual(textPassword, textPasswordConfirm)) {
+            message = "Passwords should be equal and non-empty";
+        } else if (!fingerAuthenticated) {
+            message = "Register your fingerprint";
+        } else {
+            return;
+        }
+
         View view = getView();
         if (view != null) {
-            Snackbar snackbar = Snackbar.make(getView(), "Passwords should be equal and non-empty", Snackbar.LENGTH_LONG);
+            Snackbar snackbar = Snackbar.make(getView(), message, Snackbar.LENGTH_LONG);
             snackbar.show();
         }
     }
+
+    @Override
+    public void onAuthenticated() {
+        fingerAuthenticated = true;
+    }
+
+    @Override
+    public void onError() {
+
+    }
 }

app/src/main/java/me/impy/aegis/CustomAuthenticationSlide.java

@@ -13,11 +13,9 @@ import android.support.v4.app.Fragment;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
-import android.widget.LinearLayout;
 import android.widget.RadioButton;
 import android.widget.RadioGroup;
 import android.widget.TextView;
-import android.widget.Toast;
 
 import com.github.paolorotolo.appintro.ISlidePolicy;
 
@@ -53,9 +51,6 @@ public class CustomAuthenticationSlide extends Fragment implements ISlidePolicy
                         break;
                     case R.id.rb_fingerprint:
                         id = CRYPT_TYPE_FINGER;
-                        // TODO: remove this
-                        group.clearCheck();
-                        Toast.makeText(context, "Fingerprint is not supported yet", Toast.LENGTH_SHORT).show();
                         break;
                     default:
                         throw new RuntimeException();

app/src/main/java/me/impy/aegis/IntroActivity.java

@@ -15,6 +15,7 @@ import javax.crypto.Cipher;
 
 import me.impy.aegis.crypto.CryptResult;
 import me.impy.aegis.crypto.MasterKey;
+import me.impy.aegis.crypto.slots.FingerprintSlot;
 import me.impy.aegis.crypto.slots.PasswordSlot;
 import me.impy.aegis.crypto.slots.SlotCollection;
 import me.impy.aegis.db.Database;
@@ -107,13 +108,13 @@ public class IntroActivity extends AppIntro {
             }
         }
 
+        SlotCollection slots = databaseFile.getSlots();
         if (cryptType != CustomAuthenticationSlide.CRYPT_TYPE_NONE) {
             try {
                 // encrypt the master key with a key derived from the user's password
                 // and add it to the list of slots
-                SlotCollection slots = databaseFile.getSlots();
                 PasswordSlot slot = new PasswordSlot();
-                Cipher cipher = authenticatedSlide.getCipher(slot, Cipher.ENCRYPT_MODE);
+                Cipher cipher = authenticatedSlide.getCipher(slot);
                 masterKey.encryptSlot(slot, cipher);
                 slots.add(slot);
             } catch (Exception e) {
@@ -122,8 +123,18 @@ public class IntroActivity extends AppIntro {
             }
         }
 
-        if (cryptType != CustomAuthenticationSlide.CRYPT_TYPE_FINGER) {
-            // TODO
+        if (cryptType == CustomAuthenticationSlide.CRYPT_TYPE_FINGER) {
+            try {
+                // encrypt the master key with the fingerprint key
+                // and add it to the list of slots
+                FingerprintSlot slot = new FingerprintSlot();
+                Cipher cipher = authenticatedSlide.getCipher(slot);
+                masterKey.encryptSlot(slot, cipher);
+                slots.add(slot);
+            } catch (Exception e) {
+                setException(e);
+                return;
+            }
         }
 
         // finally, save the database

app/src/main/java/me/impy/aegis/crypto/slots/Slot.java

@@ -25,7 +25,7 @@ public abstract class Slot implements Serializable {
     // getKey decrypts the encrypted master key in this slot with the given key and returns it.
     public SecretKey getKey(Cipher cipher) throws BadPaddingException, IllegalBlockSizeException {
         byte[] decryptedKeyBytes = cipher.doFinal(_encryptedMasterKey);
-        SecretKey decryptedKey = new SecretKeySpec(decryptedKeyBytes, CryptoUtils.CRYPTO_CIPHER_RAW);
+        SecretKey decryptedKey = new SecretKeySpec(decryptedKeyBytes, CryptoUtils.CRYPTO_CIPHER_AEAD);
         CryptoUtils.zero(decryptedKeyBytes);
         return decryptedKey;
     }

app/src/main/java/me/impy/aegis/finger/FingerprintUiHelper.java

@@ -1,4 +1,5 @@
-package me.impy.aegis.finger;
+// This file was originally taken from https://github.com/googlesamples/android-FingerprintDialog/blob/2feb02945ae220ebd1bc2c2b620a1d43e30daea8/Application/src/main/java/com/example/android/fingerprintdialog/FingerprintUiHelper.java
+// It has been modified to suit Aegis' needs
 
 /*
  * Copyright (C) 2015 The Android Open Source Project
@@ -16,6 +17,8 @@ package me.impy.aegis.finger;
  * limitations under the License
  */
 
+package me.impy.aegis.finger;
+
 import android.hardware.fingerprint.FingerprintManager;
 import android.os.Build;
 import android.os.CancellationSignal;
@@ -109,8 +112,6 @@ public class FingerprintUiHelper extends FingerprintManager.AuthenticationCallba
     public void onAuthenticationSucceeded(FingerprintManager.AuthenticationResult result) {
         mErrorTextView.removeCallbacks(mResetErrorTextRunnable);
         mIcon.setImageResource(R.drawable.ic_fingerprint_success);
-        mErrorTextView.setTextColor(
-                mErrorTextView.getResources().getColor(R.color.success_color, null));
         mErrorTextView.setText(
                 mErrorTextView.getResources().getString(R.string.fingerprint_success));
         mIcon.postDelayed(new Runnable() {
@@ -124,8 +125,6 @@ public class FingerprintUiHelper extends FingerprintManager.AuthenticationCallba
     private void showError(CharSequence error) {
         mIcon.setImageResource(R.drawable.ic_fingerprint_error);
         mErrorTextView.setText(error);
-        mErrorTextView.setTextColor(
-                mErrorTextView.getResources().getColor(R.color.warning_color, null));
         mErrorTextView.removeCallbacks(mResetErrorTextRunnable);
         mErrorTextView.postDelayed(mResetErrorTextRunnable, ERROR_TIMEOUT_MILLIS);
     }
@@ -133,8 +132,6 @@ public class FingerprintUiHelper extends FingerprintManager.AuthenticationCallba
     private Runnable mResetErrorTextRunnable = new Runnable() {
         @Override
         public void run() {
-            mErrorTextView.setTextColor(
-                    mErrorTextView.getResources().getColor(R.color.hint_color, null));
             mErrorTextView.setText(
                     mErrorTextView.getResources().getString(R.string.fingerprint_hint));
             mIcon.setImageResource(R.drawable.ic_fp_40px);
@@ -147,4 +144,4 @@ public class FingerprintUiHelper extends FingerprintManager.AuthenticationCallba
 
         void onError();
     }
-}
+}

app/src/main/java/me/impy/aegis/helpers/AuthHelper.java

@@ -0,0 +1,38 @@
+package me.impy.aegis.helpers;
+
+import android.text.Editable;
+import android.widget.EditText;
+
+import java.util.Arrays;
+
+import me.impy.aegis.crypto.CryptoUtils;
+
+public class AuthHelper {
+    private AuthHelper() {
+    }
+
+    public static char[] getPassword(EditText text, boolean clear) {
+        char[] password = getEditTextChars(text);
+        if (clear) {
+            text.getText().clear();
+        }
+        return password;
+    }
+
+    public static char[] getEditTextChars(EditText text) {
+        Editable editable = text.getText();
+        char[] chars = new char[editable.length()];
+        editable.getChars(0, editable.length(), chars, 0);
+        return chars;
+    }
+
+    public static boolean arePasswordsEqual(EditText text1, EditText text2) {
+        char[] password = getEditTextChars(text1);
+        char[] passwordConfirm = getEditTextChars(text2);
+        boolean equal = password.length != 0 && Arrays.equals(password, passwordConfirm);
+        CryptoUtils.zero(password);
+        CryptoUtils.zero(passwordConfirm);
+        return equal;
+    }
+
+}

app/src/main/res/layout/activity_auth.xml

@@ -8,8 +8,8 @@
     tools:context="me.impy.aegis.AuthActivity">
     <LinearLayout
         android:orientation="vertical"
-        android:layout_width="344dp"
-        android:layout_height="495dp"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
         android:layout_margin="32dp"
         tools:layout_editor_absoluteY="8dp"
         tools:layout_editor_absoluteX="8dp">
@@ -40,5 +40,26 @@
                 android:layout_height="wrap_content"
                 android:text="Decrypt" />
         </LinearLayout>
+        <LinearLayout
+            android:id="@+id/box_fingerprint"
+            android:orientation="horizontal"
+            android:layout_width="match_parent"
+            android:layout_height="match_parent"
+            android:layout_marginTop="12dp"
+            android:visibility="invisible">
+
+            <ImageView
+                android:id="@+id/img_fingerprint"
+                android:layout_width="60dp"
+                android:layout_height="60dp" />
+
+            <TextView
+                android:id="@+id/text_fingerprint"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:layout_gravity="center_vertical"
+                android:layout_marginLeft="15dp"
+                android:text="Touch sensor"/>
+        </LinearLayout>
     </LinearLayout>
 </android.support.design.widget.CoordinatorLayout>

app/src/main/res/layout/fragment_authenticated_slide.xml

@@ -17,7 +17,7 @@
     <LinearLayout
         android:orientation="vertical"
         android:layout_width="match_parent"
-        android:layout_height="match_parent"
+        android:layout_height="wrap_content"
         android:layout_marginTop="12dp">
 
         <TextView
@@ -61,4 +61,42 @@
 
     </LinearLayout>
 
+    <LinearLayout
+        android:id="@+id/box_fingerprint"
+        android:orientation="vertical"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="20dp"
+        android:visibility="invisible">
+
+        <TextView
+            android:text="Fingerprint"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:textSize="24sp"
+            android:textColor="@color/primary_text_inverted"/>
+
+        <LinearLayout
+            android:orientation="horizontal"
+            android:layout_width="match_parent"
+            android:layout_height="match_parent"
+            android:layout_marginTop="12dp">
+
+            <ImageView
+                android:id="@+id/img_fingerprint"
+                android:layout_width="60dp"
+                android:layout_height="60dp" />
+
+            <TextView
+                android:id="@+id/text_fingerprint"
+                android:textColor="@color/primary_text_inverted"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:layout_gravity="center_vertical"
+                android:layout_marginLeft="15dp"
+                android:text="Touch sensor"/>
+        </LinearLayout>
+
+    </LinearLayout>
+
 </LinearLayout>