1 page.title=Device Administration 2 page.tags=devicepolicymanager,policy,security 3 @jd:body 4 5 <div id="qv-wrapper"> 6 <div id="qv"> 7 <h2>In this document</h2> 8 <ol> 9 <li><a href="#overview">Device Administration API Overview</a> 10 <ol> 11 <li><a href="#how">How does it work?</a></li> 12 <li><a href="#policies">Policies</a></li> 13 </ol> 14 </li> 15 <li><a href="#sample">Sample Application</a></li> 16 <li><a href="#developing">Developing a Device Administration Application</a> 17 <ol> 18 <li><a href="#manifest">Creating the manifest</a></li> 19 <li><a href="#code">Implementing the code</a></li> 20 </ol> 21 </li> 22 23 </ol> 24 25 <h2>Key classes</h2> 26 <ol> 27 <li>{@link android.app.admin.DeviceAdminReceiver}</li> 28 <li>{@link android.app.admin.DevicePolicyManager}</li> 29 <li>{@link android.app.admin.DeviceAdminInfo}</li> 30 </ol> 31 </div> 32 </div> 33 34 <p>Android 2.2 introduces support for enterprise applications by offering the 35 Android Device Administration API. The Device Administration API provides device 36 administration features at the system level. These APIs allow you to create 37 security-aware applications that are useful in enterprise settings, in which IT 38 professionals require rich control over employee devices. For example, the 39 built-in Android Email application has leveraged the new APIs to improve 40 Exchange support. Through the Email application, Exchange administrators can 41 enforce password policies — including alphanumeric passwords or numeric 42 PINs — across devices. Administrators can also remotely wipe (that is, 43 restore factory defaults on) lost or stolen handsets. Exchange users can sync 44 their email and calendar data.</p> 45 46 <p>This document is intended for developers who want to develop enterprise 47 solutions for Android-powered devices. It discusses the various features 48 provided by the Device Administration API to provide stronger security for 49 employee devices that are powered by Android.</p> 50 51 <p class="note"> 52 <strong>Note</strong> For information on building a Work Policy 53 Controller for Android for Work deployments, see 54 <a href="https://developers.google.com/android/work/build-dpc" 55 >Build a Device Policy Controller</a>. 56 </p> 57 58 <h2 id="overview">Device Administration API Overview</h2> 59 60 <p>Here are examples of the types of applications that might use the Device Administration API:</p> 61 <ul> 62 <li>Email clients.</li> 63 <li>Security applications that do remote wipe.</li> 64 <li>Device management services and applications.</li> 65 </ul> 66 67 <h3 id="how">How does it work?</h3> 68 <p>You use the Device Administration API to write device admin applications that users 69 install on their devices. The device admin application enforces the desired 70 policies. Here's how it works:</p> <ul> 71 <li>A system administrator writes a device admin application that enforces 72 remote/local device security policies. These policies could be hard-coded into 73 the app, or the application could dynamically fetch policies from a third-party 74 server. </li> 75 <li>The application is installed on users' devices. Android does 76 not currently have an automated provisioning solution. Some of the ways a sysadmin might 77 distribute the application to users are as follows: 78 <ul> 79 <li>Google Play.</li> 80 <li>Enabling installation from another store.</li> 81 <li>Distributing the application through other means, such as email or websites.</li> 82 83 </ul> 84 85 86 </li> 87 <li>The system prompts the user to enable the device admin application. How 88 and when this happens depends on how the application is implemented.</li> 89 <li>Once users enable the device admin application, they are subject to 90 its policies. Complying with those policies typically confers benefits, such as 91 access to sensitive systems and data.</li> 92 </ul> 93 <p>If users do not enable the device admin app, it remains on the device, but in an inactive state. Users will not be subject to its policies, and they will conversely not get any of the application's benefits—for example, they may not be able to sync data.</p> 94 <p>If a user fails to comply with the policies (for example, if a user sets a 95 password that violates the guidelines), it is up to the application to decide 96 how to handle this. However, typically this will result in the user not being 97 able to sync data.</p> 98 <p>If a device attempts to connect to a server that requires policies not 99 supported in the Device Administration API, the connection will not 100 be allowed. The Device Administration API does not currently allow partial 101 provisioning. In other words, if a device (for example, a legacy device) does 102 not support all of the stated policies, there is no way to allow the 103 device to connect.</p> 104 <p>If a device contains multiple enabled admin applications, the strictest policy is 105 enforced. There is no way to target a particular admin 106 application.</p> 107 <p>To uninstall an existing device admin application, users need to 108 first unregister the application as an administrator. </p> 109 110 111 <h3 id="policies">Policies</h3> 112 113 <p>In an enterprise setting, it's often the case that employee devices must 114 adhere to a strict set of policies that govern the use of the device. The 115 Device Administration API supports the policies listed in Table 1. 116 Note that the Device Administration API currently only supports passwords for screen 117 lock:</p> 118 <p class="table-caption"><strong>Table 1.</strong> Policies supported by the Device Administration API.</p> 119 <table border="1"> 120 <tr> 121 <th>Policy</th> 122 <th>Description</th> 123 </tr> 124 <tr> 125 <td>Password enabled</td> 126 <td>Requires that devices ask for PIN or passwords.</td> 127 </tr> 128 <tr> 129 <td>Minimum password length</td> 130 <td>Set the required number of characters for the password. For example, you 131 can require PIN or passwords to have at least six characters. </td> </tr> 132 <tr> 133 <td>Alphanumeric password required</td> 134 <td>Requires that passwords have a 135 combination of letters and numbers. They may include symbolic characters. 136 </td> 137 </tr> 138 139 <tr> 140 <td>Complex password required</td> 141 <td>Requires that passwords must contain at least a letter, a numerical digit, and a special symbol. Introduced in Android 3.0. 142 </td> 143 </tr> 144 145 <tr> 146 <td>Minimum letters required in password</td> <td>The minimum number of 147 letters required in the password for all admins or a particular one. Introduced in Android 3.0.</td> 148 </tr> 149 150 151 <tr> 152 <td>Minimum lowercase letters required in password</td> 153 <td>The minimum number of lowercase 154 letters required in the password for all admins or a particular one. Introduced in Android 3.0.</td> 155 </tr> 156 157 <tr> 158 <td>Minimum non-letter characters required in password</td> 159 <td>The minimum number of 160 non-letter characters required in the password for all admins or a particular one. Introduced in Android 3.0.</td> 161 </tr> 162 163 <tr> 164 <td>Minimum numerical digits required in password</td> 165 <td>The minimum number of numerical digits required in the password for all admins or a particular one. Introduced in Android 3.0.</td> 166 </tr> 167 168 <tr> 169 <td>Minimum symbols required in password</td> 170 <td>The minimum number of symbols required in the password for all admins or a particular one. Introduced in Android 3.0.</td> 171 </tr> 172 173 <tr> 174 <td>Minimum uppercase letters required in password</td> 175 <td>The minimum number of uppercase letters required in the password for all admins or a particular one. Introduced in Android 3.0.</td> 176 </tr> 177 178 <tr> 179 <td>Password expiration timeout</td> 180 <td>When the password will expire, expressed as a delta in milliseconds from when a device admin sets the expiration timeout. Introduced in Android 3.0.</td> 181 </tr> 182 183 <tr> 184 <td>Password history restriction</td> 185 <td>This policy prevents users from reusing the last <em>n</em> unique passwords. 186 This policy is typically used in conjunction with 187 {@link android.app.admin.DevicePolicyManager#setPasswordExpirationTimeout(android.content.ComponentName,long) setPasswordExpirationTimeout()}, which forces 188 users to update their passwords after a specified amount of time has elapsed. 189 Introduced in Android 3.0.</td> 190 </tr> 191 192 <tr> 193 <td>Maximum failed password attempts </td> 194 <td>Specifies how many times a user can enter the wrong password before the 195 device wipes its data. The Device Administration API also allows administrators to 196 remotely reset the device to factory defaults. This secures data in case the 197 device is lost or stolen.</td> 198 </tr> 199 <tr> 200 <td>Maximum inactivity time lock</td> 201 <td>Sets the length of time since the user last touched the screen or 202 pressed a button before the device locks the screen. When this happens, users 203 need to enter their PIN or passwords again before they can use their devices and 204 access data. The value can be between 1 and 60 minutes.</td> </tr> 205 206 <tr> 207 <td>Require storage encryption</td> 208 <td>Specifies that the storage area should be encrypted, if the device supports it. 209 Introduced in Android 3.0.</td> </tr> 210 211 <tr> 212 <td>Disable camera</td> 213 214 <td>Specifies that the camera should be disabled. Note that this doesn't have 215 to be a permanent disabling. The camera can be enabled/disabled dynamically 216 based on context, time, and so on. Introduced in Android 4.0.</td> 217 218 </tr> 219 220 221 </table> 222 223 <h4>Other features</h4> 224 225 <p>In addition to supporting the policies listed in the above table, the Device 226 Administration API lets you do the following:</p> <ul> 227 <li>Prompt user to set a new password.</li> 228 <li>Lock device immediately.</li> 229 <li>Wipe the device's data (that is, restore the device to its factory defaults).</li> 230 </ul> 231 232 233 <h2 id="sample">Sample Application</h2> 234 235 <p>The examples used in this document are based on the Device Administration API 236 sample, which is included in the SDK samples (available through the 237 Android SDK Manager) and located on your system as 238 <code><sdk_root>/ApiDemos/app/src/main/java/com/example/android/apis/app/DeviceAdminSample.java</code>.</p> 239 240 <p>The sample application offers a demo of device admin features. It presents users 241 with a user interface that lets them enable the device admin application. Once 242 they've enabled the application, they can use the buttons in the user interface 243 to do the following:</p> 244 <ul> 245 <li>Set password quality.</li> 246 <li>Specify requirements for the user's password, such as minimum length, the minimum number of 247 numeric characters it must contain, and so on.</li> 248 <li>Set the password. If the password does not conform to the specified 249 policies, the system returns an error.</li> 250 <li>Set how many failed password attempts can occur before the device is wiped 251 (that is, restored to factory settings).</li> 252 <li>Set how long from now the password will expire.</li> 253 <li>Set the password history length (<em>length</em> refers to number of old passwords stored in the history). 254 This prevents users from reusing 255 one of the last <em>n</em> passwords they previously used.</li> 256 <li>Specify that the storage area should be encrypted, if the device supports it.</li> 257 <li>Set the maximum amount of inactive time that can elapse before the device 258 locks.</li> 259 <li>Make the device lock immediately.</li> 260 <li>Wipe the device's data (that is, restore factory settings).</li> 261 <li>Disable the camera.</li> 262 263 </ul> 264 265 266 267 <img src="{@docRoot}images/admin/device-admin-app.png"/> 268 269 <p class="img-caption"><strong>Figure 1.</strong> Screenshot of the Sample Application</p> 270 271 272 273 <h2 id="developing">Developing a Device Administration Application</h2> 274 275 <p>System administrators can use the Device Administration API to write an application 276 that enforces remote/local device security policy enforcement. This section 277 summarizes the steps involved in creating a device administration 278 application.</p> 279 280 <h3 id="manifest">Creating the manifest</h3> 281 282 <p>To use the Device Administration API, the application's 283 manifest must include the following:</p> 284 <ul> 285 <li>A subclass of {@link android.app.admin.DeviceAdminReceiver} that includes the following: 286 <ul> 287 <li>The {@link android.Manifest.permission#BIND_DEVICE_ADMIN} permission.</li> 288 <li>The ability to respond to the {@link android.app.admin.DeviceAdminReceiver#ACTION_DEVICE_ADMIN_ENABLED} 289 intent, expressed in the manifest as an intent filter.</li> 290 </ul> 291 </li> 292 <li>A declaration of security policies used in metadata.</li> 293 </ul> 294 <p>Here is an excerpt from the Device Administration sample manifest:</p> 295 <pre><activity android:name=".app.DeviceAdminSample" 296 android:label="@string/activity_sample_device_admin"> 297 <intent-filter> 298 <action android:name="android.intent.action.MAIN" /> 299 <category android:name="android.intent.category.SAMPLE_CODE" /> 300 </intent-filter> 301 </activity> 302 <receiver android:name=".app.DeviceAdminSample$DeviceAdminSampleReceiver" 303 android:label="@string/sample_device_admin" 304 android:description="@string/sample_device_admin_description" 305 android:permission="android.permission.BIND_DEVICE_ADMIN"> 306 <meta-data android:name="android.app.device_admin" 307 android:resource="@xml/device_admin_sample" /> 308 <intent-filter> 309 <action android:name="android.app.action.DEVICE_ADMIN_ENABLED" /> 310 </intent-filter> 311 </receiver></pre> 312 313 <p>Note that:</p> 314 <ul> 315 <li>The following attributes refer to string resources that for the sample application reside in 316 <code>ApiDemos/res/values/strings.xml</code>. For more information about resources, see 317 <a 318 href="{@docRoot}guide/topics/resources/index.html">Application Resources</a>. 319 <ul> 320 <li><code>android:label="@string/activity_sample_device_admin"</code> refers to the 321 user-readable label for the activity.</li> 322 323 <li><code>android:label="@string/sample_device_admin"</code> refers to the 324 user-readable label for the permission.</li> 325 326 <li><code>android:description="@string/sample_device_admin_description"</code> refers to 327 the user-readable description of the permission. A descripton is typically longer and more 328 informative than 329 a label.</li> 330 </ul> 331 332 333 <li><code>android:permission="android.permission.BIND_DEVICE_ADMIN" 334 </code> is a permission that a {@link android.app.admin.DeviceAdminReceiver} subclass must 335 have, to ensure that only the system can interact with the receiver (no application can be granted this permission). This 336 prevents other applications from abusing your device admin app.</li> 337 <li><code>android.app.action.DEVICE_ADMIN_ENABLED</code> is the primary 338 action that a {@link android.app.admin.DeviceAdminReceiver} subclass must handle to be 339 allowed to manage a device. This is set to the receiver when the user enables 340 the device admin app. Your code typically handles this in 341 {@link android.app.admin.DeviceAdminReceiver#onEnabled onEnabled()}. To be supported, the receiver must also 342 require the {@link android.Manifest.permission#BIND_DEVICE_ADMIN} permission so that other applications 343 cannot abuse it. </li> 344 <li>When a user enables the device admin application, that gives the receiver 345 permission to perform actions in response to the broadcast of particular system 346 events. When suitable event arises, the application can impose a policy. For 347 example, if the user attempts to set a new password that doesn't meet the policy 348 requirements, the application can prompt the user to pick a different password 349 that does meet the requirements.</li> 350 351 <li><code>android:resource="@xml/device_admin_sample"</code> 352 declares the security policies used in metadata. The metadata provides additional 353 information specific to the device administrator, as parsed by the {@link 354 android.app.admin.DeviceAdminInfo} class. Here are the contents of 355 <code>device_admin_sample.xml</code>:</li> 356 </ul> 357 <pre><device-admin xmlns:android="http://schemas.android.com/apk/res/android"> 358 <uses-policies> 359 <limit-password /> 360 <watch-login /> 361 <reset-password /> 362 <force-lock /> 363 <wipe-data /> 364 <expire-password /> 365 <encrypted-storage /> 366 <disable-camera /> 367 </uses-policies> 368 </device-admin> 369 </pre> 370 <p> In designing your device administration application, you don't need to 371 include all of the policies, just the ones that are relevant for your app. 372 </p> 373 For more discussion of the manifest file, see the <a 374 href="{@docRoot}guide/topics/manifest/manifest-intro.html">Android Developers Guide</a>. 375 376 377 378 <h3 id="code">Implementing the code</h3> 379 380 <p>The Device Administration API includes the following classes:</p> 381 <dl> 382 <dt>{@link android.app.admin.DeviceAdminReceiver}</dt> 383 <dd>Base class for implementing a device administration component. This class provides 384 a convenience for interpreting the raw intent actions that are sent by the 385 system. Your Device Administration application must include a 386 {@link android.app.admin.DeviceAdminReceiver} subclass.</dd> 387 <dt>{@link android.app.admin.DevicePolicyManager}</dt> 388 <dd>A class for managing policies enforced on a device. Most clients of 389 this class must have published a {@link android.app.admin.DeviceAdminReceiver} that the user 390 has currently enabled. The {@link android.app.admin.DevicePolicyManager} manages policies for 391 one or more {@link android.app.admin.DeviceAdminReceiver} instances</dd> 392 <dt>{@link android.app.admin.DeviceAdminInfo}</dt> 393 <dd>This class is used to specify metadata 394 for a device administrator component.</dd> 395 </dl> 396 <p>These classes provide the foundation for a fully functional device administration application. 397 The rest of this section describes how you use the {@link 398 android.app.admin.DeviceAdminReceiver} and 399 {@link android.app.admin.DevicePolicyManager} APIs to write a device admin application.</p> 400 401 <h4 id="receiver">Subclassing DeviceAdminReceiver</h4> 402 <p>To create a device admin application, you must subclass 403 {@link android.app.admin.DeviceAdminReceiver}. The {@link android.app.admin.DeviceAdminReceiver} class 404 consists of a series of callbacks that are triggered when particular events 405 occur.</p> 406 <p>In its {@link android.app.admin.DeviceAdminReceiver} subclass, the sample application 407 simply displays a {@link android.widget.Toast} notification in response to particular 408 events. For example:</p> 409 <pre>public class DeviceAdminSample extends DeviceAdminReceiver { 410 411 void showToast(Context context, String msg) { 412 String status = context.getString(R.string.admin_receiver_status, msg); 413 Toast.makeText(context, status, Toast.LENGTH_SHORT).show(); 414 } 415 416 @Override 417 public void onEnabled(Context context, Intent intent) { 418 showToast(context, context.getString(R.string.admin_receiver_status_enabled)); 419 } 420 421 @Override 422 public CharSequence onDisableRequested(Context context, Intent intent) { 423 return context.getString(R.string.admin_receiver_status_disable_warning); 424 } 425 426 @Override 427 public void onDisabled(Context context, Intent intent) { 428 showToast(context, context.getString(R.string.admin_receiver_status_disabled)); 429 } 430 431 @Override 432 public void onPasswordChanged(Context context, Intent intent) { 433 showToast(context, context.getString(R.string.admin_receiver_status_pw_changed)); 434 } 435 ... 436 }</pre> 437 438 439 <h4 id="enabling">Enabling the application</h4> 440 <p>One of the major events a device admin application has to handle is the user 441 enabling the application. The user must explicitly enable the application for 442 the policies to be enforced. If the user chooses not to enable the application 443 it will still be present on the device, but its policies will not be enforced, and the user will not 444 get any of the application's benefits.</p> 445 <p>The process of enabling the application begins when the user performs an 446 action that triggers the {@link android.app.admin.DevicePolicyManager#ACTION_ADD_DEVICE_ADMIN} 447 intent. In the 448 sample application, this happens when the user clicks the <strong>Enable 449 Admin</strong> checkbox. </p> 450 <p>When the user clicks the <strong>Enable Admin</strong> checkbox, the display 451 changes to prompt the user to activate the device admin application, as shown in figure 452 2.</p> 453 454 <img src="{@docRoot}images/admin/device-admin-activate-prompt.png"/> 455 <p class="img-caption"><strong>Figure 2.</strong> Sample Application: Activating the Application</p> 456 457 <p>Below is the code that gets executed when the user clicks the <strong>Enable Admin</strong> checkbox. This has the effect of triggering the 458 {@link android.preference.Preference.OnPreferenceChangeListener#onPreferenceChange(android.preference.Preference, java.lang.Object) onPreferenceChange()} 459 callback. This callback is invoked when the value of this {@link android.preference.Preference} has been changed by the user and is about to be set and/or persisted. If the user is enabling the application, the display 460 changes to prompt the user to activate the device admin application, as shown in figure 461 2. Otherwise, the device admin application is disabled. </p> 462 463 <pre>@Override 464 public boolean onPreferenceChange(Preference preference, Object newValue) { 465 if (super.onPreferenceChange(preference, newValue)) { 466 return true; 467 } 468 boolean value = (Boolean) newValue; 469 if (preference == mEnableCheckbox) { 470 if (value != mAdminActive) { 471 if (value) { 472 // Launch the activity to have the user enable our admin. 473 Intent intent = new Intent(DevicePolicyManager.ACTION_ADD_DEVICE_ADMIN); 474 intent.putExtra(DevicePolicyManager.EXTRA_DEVICE_ADMIN, mDeviceAdminSample); 475 intent.putExtra(DevicePolicyManager.EXTRA_ADD_EXPLANATION, 476 mActivity.getString(R.string.add_admin_extra_app_text)); 477 startActivityForResult(intent, REQUEST_CODE_ENABLE_ADMIN); 478 // return false - don't update checkbox until we're really active 479 return false; 480 } else { 481 mDPM.removeActiveAdmin(mDeviceAdminSample); 482 enableDeviceCapabilitiesArea(false); 483 mAdminActive = false; 484 } 485 } 486 } else if (preference == mDisableCameraCheckbox) { 487 mDPM.setCameraDisabled(mDeviceAdminSample, value); 488 ... 489 } 490 return true; 491 }</pre> 492 493 494 <p>The line 495 <code>intent.putExtra(DevicePolicyManager.EXTRA_DEVICE_ADMIN, 496 mDeviceAdminSample)</code> states that <code>mDeviceAdminSample</code> (which is 497 a {@link android.app.admin.DeviceAdminReceiver} component) is the target policy. 498 This line invokes the user interface shown in figure 2, which guides users through 499 adding the device administrator to the system (or allows them to reject it).</p> 500 501 <p>When the application needs to perform an operation that is contingent on the 502 device admin application being enabled, it confirms that the application is 503 active. To do this it uses the {@link android.app.admin.DevicePolicyManager} method 504 {@link android.app.admin.DevicePolicyManager#isAdminActive(android.content.ComponentName) isAdminActive()}. Notice that the {@link android.app.admin.DevicePolicyManager} 505 method {@link android.app.admin.DevicePolicyManager#isAdminActive(android.content.ComponentName) isAdminActive()} takes a {@link android.app.admin.DeviceAdminReceiver} 506 component as its argument:</p> 507 508 <pre> 509 DevicePolicyManager mDPM; 510 ... 511 private boolean isActiveAdmin() { 512 return mDPM.isAdminActive(mDeviceAdminSample); 513 } 514 </pre> 515 516 517 518 <h3 id="admin_ops">Managing policies</h3> 519 <p>{@link android.app.admin.DevicePolicyManager} is a public class for managing policies 520 enforced on a device. {@link android.app.admin.DevicePolicyManager} manages policies for one 521 or more {@link android.app.admin.DeviceAdminReceiver} instances. </p> 522 <p>You get a handle to the {@link android.app.admin.DevicePolicyManager} as follows: </p> 523 <pre> 524 DevicePolicyManager mDPM = 525 (DevicePolicyManager)getSystemService(Context.DEVICE_POLICY_SERVICE); 526 </pre> 527 <p>This section describes how to use {@link android.app.admin.DevicePolicyManager} to perform 528 administrative tasks:</p> 529 <ul> 530 <li><a href="#pwd">Set password policies</a></li> 531 <li><a href="#lock">Set device lock</a></li> 532 <li><a href="#wipe">Perform data wipe</a></li> 533 </ul> 534 535 <h4 id="pwd">Set password policies</h4> 536 <p>{@link android.app.admin.DevicePolicyManager} includes APIs for setting and enforcing the 537 device password policy. In the Device Administration API, the password only applies to 538 screen lock. This section describes common password-related tasks.</p> 539 540 <h5>Set a password for the device</h5> 541 <p>This code displays a user interface prompting the user to set a password:</p> 542 <pre>Intent intent = new Intent(DevicePolicyManager.ACTION_SET_NEW_PASSWORD); 543 startActivity(intent); 544 </pre> 545 546 <h5>Set the password quality</h5> 547 <p>The password quality can be one of the following {@link android.app.admin.DevicePolicyManager} constants: </p> 548 <dl> 549 <dt>{@link android.app.admin.DevicePolicyManager#PASSWORD_QUALITY_ALPHABETIC}</dt><dd>The user must enter a 550 password containing at least alphabetic (or other symbol) characters.</dd> 551 <dt>{@link android.app.admin.DevicePolicyManager#PASSWORD_QUALITY_ALPHANUMERIC}</dt><dd>The user must enter a 552 password containing at least <em>both</em> numeric <em>and</em> alphabetic (or 553 other symbol) characters.</dd> 554 <dt>{@link android.app.admin.DevicePolicyManager#PASSWORD_QUALITY_NUMERIC}</dt><dd>The user must enter a password 555 containing at least numeric characters.</dd> 556 <dt>{@link 557 android.app.admin.DevicePolicyManager#PASSWORD_QUALITY_COMPLEX}</dt><dd>The user 558 must have entered a password containing at least a letter, a numerical digit and 559 a special symbol.</dd> 560 <dt>{@link 561 android.app.admin.DevicePolicyManager#PASSWORD_QUALITY_SOMETHING}</dt><dd>The 562 policy requires some kind 563 of password, but doesn't care what it is.</dd> 564 <dt>{@link android.app.admin.DevicePolicyManager#PASSWORD_QUALITY_UNSPECIFIED}</dt><dd> 565 The policy has no requirements for the password. </dd> 566 </dl> 567 <p>For example, this is how you would set the password policy to require an alphanumeric password:</p> 568 <pre> 569 DevicePolicyManager mDPM; 570 ComponentName mDeviceAdminSample; 571 ... 572 mDPM.setPasswordQuality(mDeviceAdminSample, DevicePolicyManager.PASSWORD_QUALITY_ALPHANUMERIC); 573 </pre> 574 575 <h5>Set password content requirements</h5> 576 577 <p>Beginning with Android 3.0, the {@link android.app.admin.DevicePolicyManager} class 578 includes methods that let you fine-tune the contents of the password. For 579 example, you could set a policy that states that passwords must contain at least 580 <em>n</em> uppercase letters. Here are the methods for fine-tuning a password's 581 contents:</p> 582 <ul> 583 584 <li>{@link android.app.admin.DevicePolicyManager#setPasswordMinimumLetters(android.content.ComponentName,int) setPasswordMinimumLetters()}</li> 585 586 <li>{@link android.app.admin.DevicePolicyManager#setPasswordMinimumLowerCase(android.content.ComponentName,int) setPasswordMinimumLowerCase()}</li> 587 588 <li>{@link android.app.admin.DevicePolicyManager#setPasswordMinimumUpperCase(android.content.ComponentName,int) setPasswordMinimumUpperCase()}</li> 589 590 <li>{@link android.app.admin.DevicePolicyManager#setPasswordMinimumNonLetter(android.content.ComponentName,int) setPasswordMinimumNonLetter()}</li> 591 592 <li>{@link android.app.admin.DevicePolicyManager#setPasswordMinimumNumeric(android.content.ComponentName,int) setPasswordMinimumNumeric()}</li> 593 594 <li>{@link android.app.admin.DevicePolicyManager#setPasswordMinimumSymbols(android.content.ComponentName,int) setPasswordMinimumSymbols()}</li> 595 </ul> 596 <p>For example, this snippet states that the password must have at least 2 uppercase letters:</p> 597 <pre> 598 DevicePolicyManager mDPM; 599 ComponentName mDeviceAdminSample; 600 int pwMinUppercase = 2; 601 ... 602 mDPM.setPasswordMinimumUpperCase(mDeviceAdminSample, pwMinUppercase);</pre> 603 604 605 <h5>Set the minimum password length</h5> 606 <p>You can specify that a password must be at least the specified minimum 607 length. For example:</p> 608 <pre>DevicePolicyManager mDPM; 609 ComponentName mDeviceAdminSample; 610 int pwLength; 611 ... 612 mDPM.setPasswordMinimumLength(mDeviceAdminSample, pwLength); 613 </pre> 614 615 <h5>Set maximum failed password attempts</h5> 616 <p>You can set the maximum number of allowed failed password attempts before the 617 device is wiped (that is, reset to factory settings). For example:</p> 618 <pre>DevicePolicyManager mDPM; 619 ComponentName mDeviceAdminSample; 620 int maxFailedPw; 621 ... 622 mDPM.setMaximumFailedPasswordsForWipe(mDeviceAdminSample, maxFailedPw);</pre> 623 624 <h5 id="expiration">Set password expiration timeout</h5> 625 <p>Beginning with Android 3.0, you can use the 626 {@link android.app.admin.DevicePolicyManager#setPasswordExpirationTimeout(android.content.ComponentName,long) setPasswordExpirationTimeout()} 627 method to set when a password will expire, expressed as a delta in milliseconds from when a device admin sets the expiration timeout. For example:</p> 628 629 <pre>DevicePolicyManager mDPM; 630 ComponentName mDeviceAdminSample; 631 long pwExpiration; 632 ... 633 mDPM.setPasswordExpirationTimeout(mDeviceAdminSample, pwExpiration); 634 </pre> 635 636 <h5 id="history">Restrict password based on history</h5> 637 638 <p>Beginning with Android 3.0, you can use the 639 {@link android.app.admin.DevicePolicyManager#setPasswordHistoryLength(android.content.ComponentName,int) setPasswordHistoryLength()} 640 method to limit users' 641 ability to reuse old passwords. This method takes a <em>length</em> 642 parameter, which specifies how many old 643 passwords are stored. When this policy is active, users cannot enter a new 644 password that matches the last <em>n</em> passwords. This prevents 645 users from using the same password over and over. This policy is typically used 646 in conjunction with 647 {@link android.app.admin.DevicePolicyManager#setPasswordExpirationTimeout(android.content.ComponentName,long) setPasswordExpirationTimeout()}, 648 which forces users 649 to update their passwords after a specified amount of time has elapsed. </p> 650 651 <p>For example, this snippet prohibits users from reusing any of their last 5 passwords:</p> 652 653 <pre>DevicePolicyManager mDPM; 654 ComponentName mDeviceAdminSample; 655 int pwHistoryLength = 5; 656 ... 657 mDPM.setPasswordHistoryLength(mDeviceAdminSample, pwHistoryLength); 658 </pre> 659 660 <h4 id="lock">Set device lock</h4> 661 <p>You can set the maximum period of user inactivity that can occur before the 662 device locks. For example:</p> 663 <pre> 664 DevicePolicyManager mDPM; 665 ComponentName mDeviceAdminSample; 666 ... 667 long timeMs = 1000L*Long.parseLong(mTimeout.getText().toString()); 668 mDPM.setMaximumTimeToLock(mDeviceAdminSample, timeMs); 669 </pre> 670 <p>You can also programmatically tell the device to lock immediately:</p> 671 <pre> 672 DevicePolicyManager mDPM; 673 mDPM.lockNow(); 674 </pre> 675 676 677 678 <h4 id="wipe">Perform data wipe</h4> 679 680 <p>You can use the {@link android.app.admin.DevicePolicyManager} method 681 {@link android.app.admin.DevicePolicyManager#wipeData wipeData()} to reset the device to factory settings. This is useful 682 if the device is lost or stolen. Often the decision to wipe the device is the 683 result of certain conditions being met. For example, you can use 684 {@link android.app.admin.DevicePolicyManager#setMaximumFailedPasswordsForWipe setMaximumFailedPasswordsForWipe()} to state that a device should be 685 wiped after a specific number of failed password attempts.</p> 686 <p>You wipe data as follows:</p> 687 <pre> 688 DevicePolicyManager mDPM; 689 mDPM.wipeData(0);</pre> 690 <p>The {@link android.app.admin.DevicePolicyManager#wipeData wipeData()} method takes as its 691 parameter a bit mask of additional options. Currently the value must be 0. </p> 692 693 <h4>Disable camera</h4> 694 <p>Beginning with Android 4.0, you can disable the camera. Note that this doesn't have to be a permanent disabling. The camera can be enabled/disabled dynamically based on context, time, and so on. </p> 695 <p>You control whether the camera is disabled by using the 696 {@link android.app.admin.DevicePolicyManager#setCameraDisabled(android.content.ComponentName, boolean) setCameraDisabled()} method. For example, this snippet sets the camera to be enabled or disabled based on a checkbox setting:</p> 697 698 <pre>private CheckBoxPreference mDisableCameraCheckbox; 699 DevicePolicyManager mDPM; 700 ComponentName mDeviceAdminSample; 701 ... 702 mDPM.setCameraDisabled(mDeviceAdminSample, mDisableCameraCheckbox.isChecked());<br /> 703 </pre> 704 705 706 <h4 id="storage">Storage encryption</h4> 707 <p>Beginning with Android 3.0, you can use the 708 {@link android.app.admin.DevicePolicyManager#setStorageEncryption(android.content.ComponentName,boolean) setStorageEncryption()} 709 method to set a policy requiring encryption of the storage area, where supported.</p> 710 711 <p>For example:</p> 712 713 <pre> 714 DevicePolicyManager mDPM; 715 ComponentName mDeviceAdminSample; 716 ... 717 mDPM.setStorageEncryption(mDeviceAdminSample, true); 718 </pre> 719 <p> 720 See the Device Administration API sample for a complete example of how to enable storage encryption. 721 </p> 722