8j8K9PvD

1/************************* pin code ********************************************/
2  public void setPinModeEnableUnable() {
3    pinCodeMode = isPinSet ? PIN_DISABLE : PIN_INITIAL_SET;
4  }
5
6  public void putIsPinCodeSet(boolean isPinCodeSet) {
7    isPinSet = isPinCodeSet;
8    settingPresenter.putIsPinCodeSet(isPinCodeSet);
9    settingPresenter.putIsPinDisplayed();
10
11    switchFragment("SettingFragment");
12  }
13
14  public void pinLaunchCheckSucceeded() {
15    MyApplication.isPinEntered = true;
16    finish();
17  }
18
19  public void showPinPeriodDialog(boolean doDisplay) {
20    if (doDisplay) {
21      checkRadioButton();
22    }
23    viewTransparent.setVisibility(doDisplay ? View.VISIBLE : View.GONE);
24    cardPinPeriod.setVisibility(doDisplay ? View.VISIBLE : View.GONE);
25  }
26
27
28  private void checkRadioButton() {
29    int pinPeriodInt = (int) settingPresenter.retrieveSecurePeriod();
30    Timber.d("SettingActivity:checkRadioButton: pinPeriodInt %s", pinPeriodInt);
31    if (pinPeriodInt < TimeUtility.MILLISECONDS_IN_MINUTE) {
32      rBtnNow.setChecked(true);
33    } else if (pinPeriodInt < TimeUtility.MILLISECONDS_IN_MINUTE * 5) {
34      rBtn1min.setChecked(true);
35    } else if (pinPeriodInt < TimeUtility.MILLISECONDS_IN_MINUTE * 15) {
36      rBtn5min.setChecked(true);
37    } else if (pinPeriodInt < TimeUtility.MILLISECONDS_IN_HOUR) {
38      rBtn15min.setChecked(true);
39    } else if (pinPeriodInt < TimeUtility.MILLISECONDS_IN_HOUR * 3) {
40      rBtn1h.setChecked(true);
41    } else {
42      rBtn3h.setChecked(true);
43    }
44  }
45
46  public void onRadioPinPeriodClicked(View view) {
47    // Is the button now checked?
48    boolean checked = ((RadioButton) view).isChecked();
49
50    // Check which radio button was clicked
51    switch (view.getId()) {
52      case R.id.radio_now_setting:
53        if (checked) {
54          pinPeriod = 0L;
55          break;
56        }
57      case R.id.radio_1_minute_setting:
58        if (checked) {
59          pinPeriod = TimeUtility.MILLISECONDS_IN_MINUTE;
60          break;
61        }
62      case R.id.radio_5_minute_setting:
63        if (checked) {
64          pinPeriod = TimeUtility.MILLISECONDS_IN_MINUTE * 5;
65          break;
66        }
67      case R.id.radio_15_minute_setting:
68        if (checked) {
69          pinPeriod = TimeUtility.MILLISECONDS_IN_MINUTE * 15;
70          break;
71        }
72      case R.id.radio_1_hour_setting:
73        if (checked) {
74          pinPeriod = TimeUtility.MILLISECONDS_IN_HOUR;
75          break;
76        }
77      case R.id.radio_3_hour_setting:
78        if (checked) {
79          pinPeriod = TimeUtility.MILLISECONDS_IN_HOUR * 3;
80          break;
81        }
82    }
83    Timber.d("SettingActivity:onRadioPinPeriodClicked: pinPeriod %s", pinPeriod);
84  }
85
86
87  @OnClick(R.id.tv_pin_period_cancel_setting)
88  void cancelSettingPinPeriod() {
89    closeDialog();
90  }
91
92  @OnClick(R.id.tv_pin_period_ok_setting)
93  void okSettingPinPeriod() {
94
95    settingPresenter.putSecurePausedPeriod(pinPeriod);
96    closeDialog();
97  }
98
99
100  @OnClick(R.id.view_transparent_setting)
101  void closeDialog() {
102    // BackupDialog の場合は、ログアウト処理とかあるから消さない
103    if (!isBackupDialogVisible) {
104      showPinPeriodDialog(false);
105    }
106  }
107
108  public void putPinCodeOnInternal(int pinCode) {
109    putEncryptedPinCode(pinCode);
110  }
111
112  public int retrievePinCodeFromInternal(int pinCode) {
113    return retrieveDecryptedData(pinCode);
114  }
115
116  /************************* 暗号化/復号化 ********************************************/
117
118  // pinCode  →秘密鍵 + 暗号化data  →書き込み
119  private void putEncryptedPinCode(int pinCode) {
120    String pinCodeStr = String.valueOf(pinCode);
121    // pinCodeStr から 秘密鍵を生成
122    SecretKey secureKey = generateSecureKeyByPassword(pinCodeStr, KEY_SIZE);
123
124    // pinCode を byte[] に変換
125    byte[] intInByteArray = ByteBuffer.allocate(4).putInt(pinCode).array();
126    // そして暗号化
127    byte[] encryptedPin = encryptData(intInByteArray, retrieveIv(), secureKey);
128
129    // 内部ストレージへ書き込み
130    writeToFile(ENCRYPTED_FILE_NAME, encryptedPin);
131    Timber.d("SettingActivity:putEncryptedPinCode: intInByteArray %s, encryptedPin %s secureKey %s",
132        intInByteArray, encryptedPin, secureKey);
133  }
134
135
136  // pinCode →秘密鍵生成 →複合に使用
137  private int retrieveDecryptedData(int pinCode) {
138
139    String pinCodeStr = String.valueOf(pinCode);
140
141    // 秘密鍵を取得
142    SecretKey secureKey = generateSecureKeyByPassword(pinCodeStr, KEY_SIZE);
143
144    // 本アプリ専用保存場所パスとファイル名とで、ファイルを取得し、そこから byte サイズを取得
145    File file = new File(context.getFilesDir(), ENCRYPTED_FILE_NAME);
146    int size = (int) file.length();
147    byte[] bytes = new byte[size];
148
149    // 内部ストレージからファイルを取得(暗号化状態)
150    readFileForPinCode(ENCRYPTED_FILE_NAME, bytes);
151    // データを復号化
152    byte[] decryptedData = decryptData(bytes, retrieveIv(), secureKey);
153
154    int returnedInt;
155    // 復号化された byte[] を int に変換
156    if (decryptedData == null) {
157      // 複合を試みた入力が間違っていた場合、null が返される
158      returnedInt = 9999999;// 4桁以上の値を返す
159    } else {
160      ByteBuffer wrapped = ByteBuffer.wrap(decryptedData); // big-endian by default
161      returnedInt = wrapped.getInt();
162    }
163    return returnedInt;
164  }
165
166  /**
167   * 入力されたパスワードから、秘密鍵を再生成して返す
168   */
169  private SecretKey generateSecureKeyByPassword(String password, int keySizeInBytes) {
170    int iterationCount = 1000;
171    // Use this to derive the key from the password:
172    KeySpec keySpec = new PBEKeySpec(password.toCharArray(), retrieveSalt(),
173        iterationCount, keySizeInBytes * 8);
174    try {
175      SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1");
176      byte[] keyBytes = keyFactory.generateSecret(keySpec).getEncoded();
177      return new SecretKeySpec(keyBytes, "AES");
178    } catch (Exception e) {
179      Timber.e("SettingActivity:generateSecureKeyByPassword: %s", e.getMessage());
180      throw new RuntimeException("Deal with exceptions properly!", e);
181    }
182  }
183
184  /********************** encrypt Or Decrypt の実行 ***************************/
185  private static byte[] encryptOrDecrypt(
186      byte[] data, SecretKey key, byte[] iv, boolean isEncrypt) {
187    try {
188      //Authenticated Encryption -> CBC(Cipher block chaining )
189      // CBC と PKCS5Padding の組み合わせは攻撃を受けるらしい
190      Cipher cipher = Cipher.getInstance("AES/CBC/PKCS7PADDING");
191
192      cipher.init(isEncrypt ? Cipher.ENCRYPT_MODE : Cipher.DECRYPT_MODE, key,
193          new IvParameterSpec(iv));
194      return cipher.doFinal(data);
195    } catch (GeneralSecurityException e) {
196      Timber.e("SettingActivity:encryptOrDecrypt: %s", e.getMessage());
197      return null;
198    }
199  }
200
201  private static byte[] encryptData(byte[] data, byte[] iv, SecretKey key) {
202    return encryptOrDecrypt(data, key, iv, true);
203  }
204
205  private static byte[] decryptData(byte[] data, byte[] iv, SecretKey key) {
206    return encryptOrDecrypt(data, key, iv, false);
207  }
208
209  /**********************  ソルト ******************************/
210  // ソルトの取得もしくは、初回であれば生成して保存
211  private byte[] retrieveSalt() {
212    // Salt must be at least the same size as the key.
213    byte[] salt = new byte[KEY_SIZE];
214    // Create a random salt if encrypting for the first time, and save it for future use.
215    readFromFileOrCreateRandom("salt", salt);
216    return salt;
217  }
218
219  /**********************  IV ******************************/
220  // initialization vector (IV)
221  // 暗号化する値 の頭につけて、毎度異なる cipher text が生成されるようにする
222  private byte[] retrieveIv() {
223    byte[] iv = new byte[IV_SIZE];
224    // Ideally your data should have been encrypted with a random iv. This creates a random iv
225    // if not present, in order to encrypt our mock data.
226    readFromFileOrCreateRandom("iv", iv);
227    return iv;
228  }
229
230  /**********************  CSPRNG セキュアなランダマイザー ***********************/
231  /**
232   * 内部ストレージにファイル "salt/iv" があるかどうか確認して、なければ生成して保存
233   */
234  private void readFromFileOrCreateRandom(String fileName, byte[] bytes) {
235    if (fileExists(fileName)) {
236      readBytesFromFile(fileName, bytes);
237      return;
238    }
239    SecureRandom sr = new SecureRandom();
240    sr.nextBytes(bytes);
241    writeToFile(fileName, bytes);
242  }
243
244  private boolean fileExists(String fileName) {
245    File file = new File(getFilesDir(), fileName);
246    return file.exists();
247  }
248
249  /**********************  内部ストレージへの 書き込み ******************************/
250  private void writeToFile(String fileName, byte[] bytes) {
251    FileOutputStream outputStream = null;
252    try {
253      outputStream = openFileOutput(fileName, Context.MODE_PRIVATE);
254      outputStream.write(bytes);
255    } catch (IOException e) {
256      Timber.e("SettingActivity:writeToFile: Couldn't write to %s, %s", fileName, e.getMessage());
257    } finally {
258      try {
259        if (outputStream != null) {
260          outputStream.flush();
261          outputStream.close();
262        }
263      } catch (IOException e) {
264        Timber.e("SettingActivity:writeToFile: %s", e.getMessage());
265      }
266    }
267  }
268
269
270  /**********************  内部ストレージからの 読み取り ******************************/
271  private void readBytesFromFile(String fileName, byte[] bytes) {
272
273    FileInputStream inputStream = null;
274    try {
275      inputStream = openFileInput(fileName);
276      int numBytes = 0;
277      while (numBytes < bytes.length) {
278        int n = inputStream.read(bytes, numBytes, bytes.length - numBytes);
279        if (n <= 0) {
280          Timber.e("SettingActivity:readBytesFromFile: Couldn't read from %s", fileName);
281        }
282        numBytes += n;
283      }
284    } catch (IOException e) {
285      Timber.e("SettingActivity:readBytesFromFile: %s", e.getMessage());
286    } finally {
287      try {
288        if (inputStream != null) {
289          inputStream.close();
290        }
291      } catch (IOException e) {
292        Timber.e("SettingActivity:readBytesFromFile: %s", e.getMessage());
293      }
294    }
295  }
296
297  private void readFileForPinCode(String fileName, byte[] bytes) {
298
299    FileInputStream inputStream = null;
300    try {
301      inputStream = openFileInput(fileName);
302      int numBytes = 0;
303      while (numBytes < bytes.length) {
304        int n = inputStream.read(bytes, numBytes, bytes.length - numBytes);
305        if (n <= 0) {
306          Timber.e("SettingActivity:readBytesFromFile: Couldn't read from %s", fileName);
307        }
308        numBytes += n;
309      }
310    } catch (IOException e) {
311      Timber.e("SettingActivity:readBytesFromFile: %s", e.getMessage());
312    } finally {
313      try {
314        if (inputStream != null) {
315          inputStream.close();
316        }
317      } catch (IOException e) {
318        Timber.e("SettingActivity:readBytesFromFile: %s", e.getMessage());
319      }
320    }
321  }