WebViewFactory.java revision bf683e07c350ed7cd2c8e877b447e1dd41863a94
1/* 2 * Copyright (C) 2012 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17package android.webkit; 18 19import android.annotation.SystemApi; 20import android.app.ActivityManagerInternal; 21import android.app.ActivityManagerNative; 22import android.app.AppGlobals; 23import android.app.Application; 24import android.content.Context; 25import android.content.pm.ApplicationInfo; 26import android.content.pm.PackageInfo; 27import android.content.pm.PackageManager; 28import android.content.pm.Signature; 29import android.os.Build; 30import android.os.Process; 31import android.os.RemoteException; 32import android.os.ServiceManager; 33import android.os.StrictMode; 34import android.os.SystemProperties; 35import android.os.Trace; 36import android.text.TextUtils; 37import android.util.AndroidRuntimeException; 38import android.util.ArraySet; 39import android.util.Log; 40 41import com.android.server.LocalServices; 42 43import dalvik.system.VMRuntime; 44 45import java.lang.reflect.Method; 46import java.io.File; 47import java.io.IOException; 48import java.util.Arrays; 49import java.util.zip.ZipEntry; 50import java.util.zip.ZipFile; 51 52/** 53 * Top level factory, used creating all the main WebView implementation classes. 54 * 55 * @hide 56 */ 57@SystemApi 58public final class WebViewFactory { 59 60 private static final String CHROMIUM_WEBVIEW_FACTORY = 61 "com.android.webview.chromium.WebViewChromiumFactoryProvider"; 62 63 private static final String CHROMIUM_WEBVIEW_FACTORY_METHOD = "create"; 64 65 private static final String NULL_WEBVIEW_FACTORY = 66 "com.android.webview.nullwebview.NullWebViewFactoryProvider"; 67 68 private static final String CHROMIUM_WEBVIEW_NATIVE_RELRO_32 = 69 "/data/misc/shared_relro/libwebviewchromium32.relro"; 70 private static final String CHROMIUM_WEBVIEW_NATIVE_RELRO_64 = 71 "/data/misc/shared_relro/libwebviewchromium64.relro"; 72 73 public static final String CHROMIUM_WEBVIEW_VMSIZE_SIZE_PROPERTY = 74 "persist.sys.webview.vmsize"; 75 private static final long CHROMIUM_WEBVIEW_DEFAULT_VMSIZE_BYTES = 100 * 1024 * 1024; 76 77 private static final String LOGTAG = "WebViewFactory"; 78 79 private static final boolean DEBUG = false; 80 81 // Cache the factory both for efficiency, and ensure any one process gets all webviews from the 82 // same provider. 83 private static WebViewFactoryProvider sProviderInstance; 84 private static final Object sProviderLock = new Object(); 85 private static boolean sAddressSpaceReserved = false; 86 private static PackageInfo sPackageInfo; 87 88 // Error codes for loadWebViewNativeLibraryFromPackage 89 public static final int LIBLOAD_SUCCESS = 0; 90 public static final int LIBLOAD_WRONG_PACKAGE_NAME = 1; 91 public static final int LIBLOAD_ADDRESS_SPACE_NOT_RESERVED = 2; 92 93 // error codes for waiting for WebView preparation 94 public static final int LIBLOAD_FAILED_WAITING_FOR_RELRO = 3; 95 public static final int LIBLOAD_FAILED_LISTING_WEBVIEW_PACKAGES = 4; 96 97 // native relro loading error codes 98 public static final int LIBLOAD_FAILED_TO_OPEN_RELRO_FILE = 5; 99 public static final int LIBLOAD_FAILED_TO_LOAD_LIBRARY = 6; 100 public static final int LIBLOAD_FAILED_JNI_CALL = 7; 101 102 // more error codes for waiting for WebView preparation 103 public static final int LIBLOAD_FAILED_WAITING_FOR_WEBVIEW_REASON_UNKNOWN = 8; 104 105 // error for namespace lookup 106 public static final int LIBLOAD_FAILED_TO_FIND_NAMESPACE = 10; 107 108 private static String getWebViewPreparationErrorReason(int error) { 109 switch (error) { 110 case LIBLOAD_FAILED_WAITING_FOR_RELRO: 111 return "Time out waiting for Relro files being created"; 112 case LIBLOAD_FAILED_LISTING_WEBVIEW_PACKAGES: 113 return "No WebView installed"; 114 case LIBLOAD_FAILED_WAITING_FOR_WEBVIEW_REASON_UNKNOWN: 115 return "Crashed for unknown reason"; 116 } 117 return "Unknown"; 118 } 119 120 /** 121 * @hide 122 */ 123 public static class MissingWebViewPackageException extends AndroidRuntimeException { 124 public MissingWebViewPackageException(String message) { super(message); } 125 public MissingWebViewPackageException(Exception e) { super(e); } 126 } 127 128 /** 129 * @hide 130 */ 131 public static String getWebViewLibrary(ApplicationInfo ai) { 132 if (ai.metaData != null) 133 return ai.metaData.getString("com.android.webview.WebViewLibrary"); 134 return null; 135 } 136 137 public static PackageInfo getLoadedPackageInfo() { 138 synchronized (sProviderLock) { 139 return sPackageInfo; 140 } 141 } 142 143 /** 144 * Load the native library for the given package name iff that package 145 * name is the same as the one providing the webview. 146 */ 147 public static int loadWebViewNativeLibraryFromPackage(String packageName, 148 ClassLoader clazzLoader) { 149 WebViewProviderResponse response = null; 150 try { 151 response = getUpdateService().waitForAndGetProvider(); 152 } catch (RemoteException e) { 153 Log.e(LOGTAG, "error waiting for relro creation", e); 154 return LIBLOAD_FAILED_WAITING_FOR_WEBVIEW_REASON_UNKNOWN; 155 } 156 157 158 if (response.status != LIBLOAD_SUCCESS 159 && response.status != LIBLOAD_FAILED_WAITING_FOR_RELRO) { 160 return response.status; 161 } 162 if (!response.packageInfo.packageName.equals(packageName)) { 163 return LIBLOAD_WRONG_PACKAGE_NAME; 164 } 165 166 PackageManager packageManager = AppGlobals.getInitialApplication().getPackageManager(); 167 PackageInfo packageInfo; 168 try { 169 packageInfo = packageManager.getPackageInfo(packageName, 170 PackageManager.GET_META_DATA | PackageManager.MATCH_DEBUG_TRIAGED_MISSING); 171 } catch (PackageManager.NameNotFoundException e) { 172 Log.e(LOGTAG, "Couldn't find package " + packageName); 173 return LIBLOAD_WRONG_PACKAGE_NAME; 174 } 175 176 int loadNativeRet = loadNativeLibrary(clazzLoader, packageInfo); 177 // If we failed waiting for relro we want to return that fact even if we successfully load 178 // the relro file. 179 if (loadNativeRet == LIBLOAD_SUCCESS) return response.status; 180 return loadNativeRet; 181 } 182 183 static WebViewFactoryProvider getProvider() { 184 synchronized (sProviderLock) { 185 // For now the main purpose of this function (and the factory abstraction) is to keep 186 // us honest and minimize usage of WebView internals when binding the proxy. 187 if (sProviderInstance != null) return sProviderInstance; 188 189 final int uid = android.os.Process.myUid(); 190 if (uid == android.os.Process.ROOT_UID || uid == android.os.Process.SYSTEM_UID) { 191 throw new UnsupportedOperationException( 192 "For security reasons, WebView is not allowed in privileged processes"); 193 } 194 195 StrictMode.ThreadPolicy oldPolicy = StrictMode.allowThreadDiskReads(); 196 Trace.traceBegin(Trace.TRACE_TAG_WEBVIEW, "WebViewFactory.getProvider()"); 197 try { 198 Class<WebViewFactoryProvider> providerClass = getProviderClass(); 199 Method staticFactory = null; 200 try { 201 staticFactory = providerClass.getMethod( 202 CHROMIUM_WEBVIEW_FACTORY_METHOD, WebViewDelegate.class); 203 } catch (Exception e) { 204 if (DEBUG) { 205 Log.w(LOGTAG, "error instantiating provider with static factory method", e); 206 } 207 } 208 209 Trace.traceBegin(Trace.TRACE_TAG_WEBVIEW, "providerClass.newInstance()"); 210 try { 211 if (staticFactory != null) { 212 sProviderInstance = (WebViewFactoryProvider) 213 staticFactory.invoke(null, new WebViewDelegate()); 214 } else { 215 sProviderInstance = providerClass.getConstructor(WebViewDelegate.class) 216 .newInstance(new WebViewDelegate()); 217 } 218 if (DEBUG) Log.v(LOGTAG, "Loaded provider: " + sProviderInstance); 219 return sProviderInstance; 220 } catch (Exception e) { 221 Log.e(LOGTAG, "error instantiating provider", e); 222 throw new AndroidRuntimeException(e); 223 } finally { 224 Trace.traceEnd(Trace.TRACE_TAG_WEBVIEW); 225 } 226 } finally { 227 Trace.traceEnd(Trace.TRACE_TAG_WEBVIEW); 228 StrictMode.setThreadPolicy(oldPolicy); 229 } 230 } 231 } 232 233 /** 234 * Returns true if the signatures match, false otherwise 235 */ 236 private static boolean signaturesEquals(Signature[] s1, Signature[] s2) { 237 if (s1 == null) { 238 return s2 == null; 239 } 240 if (s2 == null) return false; 241 242 ArraySet<Signature> set1 = new ArraySet<>(); 243 for(Signature signature : s1) { 244 set1.add(signature); 245 } 246 ArraySet<Signature> set2 = new ArraySet<>(); 247 for(Signature signature : s2) { 248 set2.add(signature); 249 } 250 return set1.equals(set2); 251 } 252 253 // Throws MissingWebViewPackageException on failure 254 private static void verifyPackageInfo(PackageInfo chosen, PackageInfo toUse) { 255 if (!chosen.packageName.equals(toUse.packageName)) { 256 throw new MissingWebViewPackageException("Failed to verify WebView provider, " 257 + "packageName mismatch, expected: " 258 + chosen.packageName + " actual: " + toUse.packageName); 259 } 260 if (chosen.versionCode > toUse.versionCode) { 261 throw new MissingWebViewPackageException("Failed to verify WebView provider, " 262 + "version code is lower than expected: " + chosen.versionCode 263 + " actual: " + toUse.versionCode); 264 } 265 if (getWebViewLibrary(toUse.applicationInfo) == null) { 266 throw new MissingWebViewPackageException("Tried to load an invalid WebView provider: " 267 + toUse.packageName); 268 } 269 if (!signaturesEquals(chosen.signatures, toUse.signatures)) { 270 throw new MissingWebViewPackageException("Failed to verify WebView provider, " 271 + "signature mismatch"); 272 } 273 } 274 275 private static Context getWebViewContextAndSetProvider() { 276 Application initialApplication = AppGlobals.getInitialApplication(); 277 try { 278 WebViewProviderResponse response = null; 279 Trace.traceBegin(Trace.TRACE_TAG_WEBVIEW, 280 "WebViewUpdateService.waitForAndGetProvider()"); 281 try { 282 response = getUpdateService().waitForAndGetProvider(); 283 } finally { 284 Trace.traceEnd(Trace.TRACE_TAG_WEBVIEW); 285 } 286 if (response.status != LIBLOAD_SUCCESS 287 && response.status != LIBLOAD_FAILED_WAITING_FOR_RELRO) { 288 throw new MissingWebViewPackageException("Failed to load WebView provider: " 289 + getWebViewPreparationErrorReason(response.status)); 290 } 291 // Register to be killed before fetching package info - so that we will be 292 // killed if the package info goes out-of-date. 293 Trace.traceBegin(Trace.TRACE_TAG_WEBVIEW, "ActivityManager.addPackageDependency()"); 294 try { 295 ActivityManagerNative.getDefault().addPackageDependency( 296 response.packageInfo.packageName); 297 } finally { 298 Trace.traceEnd(Trace.TRACE_TAG_WEBVIEW); 299 } 300 // Fetch package info and verify it against the chosen package 301 PackageInfo newPackageInfo = null; 302 Trace.traceBegin(Trace.TRACE_TAG_WEBVIEW, "PackageManager.getPackageInfo()"); 303 try { 304 newPackageInfo = initialApplication.getPackageManager().getPackageInfo( 305 response.packageInfo.packageName, 306 PackageManager.GET_SHARED_LIBRARY_FILES 307 | PackageManager.MATCH_DEBUG_TRIAGED_MISSING 308 // Make sure that we fetch the current provider even if its not 309 // installed for the current user 310 | PackageManager.MATCH_UNINSTALLED_PACKAGES 311 // Fetch signatures for verification 312 | PackageManager.GET_SIGNATURES 313 // Get meta-data for meta data flag verification 314 | PackageManager.GET_META_DATA); 315 } finally { 316 Trace.traceEnd(Trace.TRACE_TAG_WEBVIEW); 317 } 318 319 // Validate the newly fetched package info, throws MissingWebViewPackageException on 320 // failure 321 verifyPackageInfo(response.packageInfo, newPackageInfo); 322 323 Trace.traceBegin(Trace.TRACE_TAG_WEBVIEW, 324 "initialApplication.createApplicationContext"); 325 try { 326 // Construct an app context to load the Java code into the current app. 327 Context webViewContext = initialApplication.createApplicationContext( 328 newPackageInfo.applicationInfo, 329 Context.CONTEXT_INCLUDE_CODE | Context.CONTEXT_IGNORE_SECURITY); 330 sPackageInfo = newPackageInfo; 331 return webViewContext; 332 } finally { 333 Trace.traceEnd(Trace.TRACE_TAG_WEBVIEW); 334 } 335 } catch (RemoteException | PackageManager.NameNotFoundException e) { 336 throw new MissingWebViewPackageException("Failed to load WebView provider: " + e); 337 } 338 } 339 340 private static Class<WebViewFactoryProvider> getProviderClass() { 341 Context webViewContext = null; 342 Application initialApplication = AppGlobals.getInitialApplication(); 343 344 try { 345 Trace.traceBegin(Trace.TRACE_TAG_WEBVIEW, 346 "WebViewFactory.getWebViewContextAndSetProvider()"); 347 try { 348 webViewContext = getWebViewContextAndSetProvider(); 349 } finally { 350 Trace.traceEnd(Trace.TRACE_TAG_WEBVIEW); 351 } 352 Log.i(LOGTAG, "Loading " + sPackageInfo.packageName + " version " + 353 sPackageInfo.versionName + " (code " + sPackageInfo.versionCode + ")"); 354 355 Trace.traceBegin(Trace.TRACE_TAG_WEBVIEW, "WebViewFactory.getChromiumProviderClass()"); 356 try { 357 initialApplication.getAssets().addAssetPathAsSharedLibrary( 358 webViewContext.getApplicationInfo().sourceDir); 359 ClassLoader clazzLoader = webViewContext.getClassLoader(); 360 361 Trace.traceBegin(Trace.TRACE_TAG_WEBVIEW, "WebViewFactory.loadNativeLibrary()"); 362 loadNativeLibrary(clazzLoader, sPackageInfo); 363 Trace.traceEnd(Trace.TRACE_TAG_WEBVIEW); 364 365 Trace.traceBegin(Trace.TRACE_TAG_WEBVIEW, "Class.forName()"); 366 try { 367 return (Class<WebViewFactoryProvider>) Class.forName(CHROMIUM_WEBVIEW_FACTORY, 368 true, clazzLoader); 369 } finally { 370 Trace.traceEnd(Trace.TRACE_TAG_WEBVIEW); 371 } 372 } catch (ClassNotFoundException e) { 373 Log.e(LOGTAG, "error loading provider", e); 374 throw new AndroidRuntimeException(e); 375 } finally { 376 Trace.traceEnd(Trace.TRACE_TAG_WEBVIEW); 377 } 378 } catch (MissingWebViewPackageException e) { 379 // If the package doesn't exist, then try loading the null WebView instead. 380 // If that succeeds, then this is a device without WebView support; if it fails then 381 // swallow the failure, complain that the real WebView is missing and rethrow the 382 // original exception. 383 try { 384 return (Class<WebViewFactoryProvider>) Class.forName(NULL_WEBVIEW_FACTORY); 385 } catch (ClassNotFoundException e2) { 386 // Ignore. 387 } 388 Log.e(LOGTAG, "Chromium WebView package does not exist", e); 389 throw new AndroidRuntimeException(e); 390 } 391 } 392 393 /** 394 * Perform any WebView loading preparations that must happen in the zygote. 395 * Currently, this means allocating address space to load the real JNI library later. 396 */ 397 public static void prepareWebViewInZygote() { 398 try { 399 System.loadLibrary("webviewchromium_loader"); 400 long addressSpaceToReserve = 401 SystemProperties.getLong(CHROMIUM_WEBVIEW_VMSIZE_SIZE_PROPERTY, 402 CHROMIUM_WEBVIEW_DEFAULT_VMSIZE_BYTES); 403 sAddressSpaceReserved = nativeReserveAddressSpace(addressSpaceToReserve); 404 405 if (sAddressSpaceReserved) { 406 if (DEBUG) { 407 Log.v(LOGTAG, "address space reserved: " + addressSpaceToReserve + " bytes"); 408 } 409 } else { 410 Log.e(LOGTAG, "reserving " + addressSpaceToReserve + 411 " bytes of address space failed"); 412 } 413 } catch (Throwable t) { 414 // Log and discard errors at this stage as we must not crash the zygote. 415 Log.e(LOGTAG, "error preparing native loader", t); 416 } 417 } 418 419 private static int prepareWebViewInSystemServer(String[] nativeLibraryPaths) { 420 if (DEBUG) Log.v(LOGTAG, "creating relro files"); 421 int numRelros = 0; 422 423 // We must always trigger createRelRo regardless of the value of nativeLibraryPaths. Any 424 // unexpected values will be handled there to ensure that we trigger notifying any process 425 // waiting on relro creation. 426 if (Build.SUPPORTED_32_BIT_ABIS.length > 0) { 427 if (DEBUG) Log.v(LOGTAG, "Create 32 bit relro"); 428 createRelroFile(false /* is64Bit */, nativeLibraryPaths); 429 numRelros++; 430 } 431 432 if (Build.SUPPORTED_64_BIT_ABIS.length > 0) { 433 if (DEBUG) Log.v(LOGTAG, "Create 64 bit relro"); 434 createRelroFile(true /* is64Bit */, nativeLibraryPaths); 435 numRelros++; 436 } 437 return numRelros; 438 } 439 440 /** 441 * @hide 442 */ 443 public static int onWebViewProviderChanged(PackageInfo packageInfo) { 444 String[] nativeLibs = null; 445 try { 446 nativeLibs = WebViewFactory.getWebViewNativeLibraryPaths(packageInfo); 447 if (nativeLibs != null) { 448 long newVmSize = 0L; 449 450 for (String path : nativeLibs) { 451 if (path == null || TextUtils.isEmpty(path)) continue; 452 if (DEBUG) Log.d(LOGTAG, "Checking file size of " + path); 453 File f = new File(path); 454 if (f.exists()) { 455 newVmSize = Math.max(newVmSize, f.length()); 456 continue; 457 } 458 if (path.contains("!/")) { 459 String[] split = TextUtils.split(path, "!/"); 460 if (split.length == 2) { 461 try (ZipFile z = new ZipFile(split[0])) { 462 ZipEntry e = z.getEntry(split[1]); 463 if (e != null && e.getMethod() == ZipEntry.STORED) { 464 newVmSize = Math.max(newVmSize, e.getSize()); 465 continue; 466 } 467 } 468 catch (IOException e) { 469 Log.e(LOGTAG, "error reading APK file " + split[0] + ", ", e); 470 } 471 } 472 } 473 Log.e(LOGTAG, "error sizing load for " + path); 474 } 475 476 if (DEBUG) { 477 Log.v(LOGTAG, "Based on library size, need " + newVmSize + 478 " bytes of address space."); 479 } 480 // The required memory can be larger than the file on disk (due to .bss), and an 481 // upgraded version of the library will likely be larger, so always attempt to 482 // reserve twice as much as we think to allow for the library to grow during this 483 // boot cycle. 484 newVmSize = Math.max(2 * newVmSize, CHROMIUM_WEBVIEW_DEFAULT_VMSIZE_BYTES); 485 Log.d(LOGTAG, "Setting new address space to " + newVmSize); 486 SystemProperties.set(CHROMIUM_WEBVIEW_VMSIZE_SIZE_PROPERTY, 487 Long.toString(newVmSize)); 488 } 489 } catch (Throwable t) { 490 // Log and discard errors at this stage as we must not crash the system server. 491 Log.e(LOGTAG, "error preparing webview native library", t); 492 } 493 return prepareWebViewInSystemServer(nativeLibs); 494 } 495 496 // throws MissingWebViewPackageException 497 private static String getLoadFromApkPath(String apkPath, 498 String[] abiList, 499 String nativeLibFileName) { 500 // Search the APK for a native library conforming to a listed ABI. 501 try (ZipFile z = new ZipFile(apkPath)) { 502 for (String abi : abiList) { 503 final String entry = "lib/" + abi + "/" + nativeLibFileName; 504 ZipEntry e = z.getEntry(entry); 505 if (e != null && e.getMethod() == ZipEntry.STORED) { 506 // Return a path formatted for dlopen() load from APK. 507 return apkPath + "!/" + entry; 508 } 509 } 510 } catch (IOException e) { 511 throw new MissingWebViewPackageException(e); 512 } 513 return ""; 514 } 515 516 // throws MissingWebViewPackageException 517 private static String[] getWebViewNativeLibraryPaths(PackageInfo packageInfo) { 518 ApplicationInfo ai = packageInfo.applicationInfo; 519 final String NATIVE_LIB_FILE_NAME = getWebViewLibrary(ai); 520 521 String path32; 522 String path64; 523 boolean primaryArchIs64bit = VMRuntime.is64BitAbi(ai.primaryCpuAbi); 524 if (!TextUtils.isEmpty(ai.secondaryCpuAbi)) { 525 // Multi-arch case. 526 if (primaryArchIs64bit) { 527 // Primary arch: 64-bit, secondary: 32-bit. 528 path64 = ai.nativeLibraryDir; 529 path32 = ai.secondaryNativeLibraryDir; 530 } else { 531 // Primary arch: 32-bit, secondary: 64-bit. 532 path64 = ai.secondaryNativeLibraryDir; 533 path32 = ai.nativeLibraryDir; 534 } 535 } else if (primaryArchIs64bit) { 536 // Single-arch 64-bit. 537 path64 = ai.nativeLibraryDir; 538 path32 = ""; 539 } else { 540 // Single-arch 32-bit. 541 path32 = ai.nativeLibraryDir; 542 path64 = ""; 543 } 544 545 // Form the full paths to the extracted native libraries. 546 // If libraries were not extracted, try load from APK paths instead. 547 if (!TextUtils.isEmpty(path32)) { 548 path32 += "/" + NATIVE_LIB_FILE_NAME; 549 File f = new File(path32); 550 if (!f.exists()) { 551 path32 = getLoadFromApkPath(ai.sourceDir, 552 Build.SUPPORTED_32_BIT_ABIS, 553 NATIVE_LIB_FILE_NAME); 554 } 555 } 556 if (!TextUtils.isEmpty(path64)) { 557 path64 += "/" + NATIVE_LIB_FILE_NAME; 558 File f = new File(path64); 559 if (!f.exists()) { 560 path64 = getLoadFromApkPath(ai.sourceDir, 561 Build.SUPPORTED_64_BIT_ABIS, 562 NATIVE_LIB_FILE_NAME); 563 } 564 } 565 566 if (DEBUG) Log.v(LOGTAG, "Native 32-bit lib: " + path32 + ", 64-bit lib: " + path64); 567 return new String[] { path32, path64 }; 568 } 569 570 private static void createRelroFile(final boolean is64Bit, String[] nativeLibraryPaths) { 571 final String abi = 572 is64Bit ? Build.SUPPORTED_64_BIT_ABIS[0] : Build.SUPPORTED_32_BIT_ABIS[0]; 573 574 // crashHandler is invoked by the ActivityManagerService when the isolated process crashes. 575 Runnable crashHandler = new Runnable() { 576 @Override 577 public void run() { 578 try { 579 Log.e(LOGTAG, "relro file creator for " + abi + " crashed. Proceeding without"); 580 getUpdateService().notifyRelroCreationCompleted(); 581 } catch (RemoteException e) { 582 Log.e(LOGTAG, "Cannot reach WebViewUpdateService. " + e.getMessage()); 583 } 584 } 585 }; 586 587 try { 588 if (nativeLibraryPaths == null 589 || nativeLibraryPaths[0] == null || nativeLibraryPaths[1] == null) { 590 throw new IllegalArgumentException( 591 "Native library paths to the WebView RelRo process must not be null!"); 592 } 593 int pid = LocalServices.getService(ActivityManagerInternal.class).startIsolatedProcess( 594 RelroFileCreator.class.getName(), nativeLibraryPaths, "WebViewLoader-" + abi, abi, 595 Process.SHARED_RELRO_UID, crashHandler); 596 if (pid <= 0) throw new Exception("Failed to start the relro file creator process"); 597 } catch (Throwable t) { 598 // Log and discard errors as we must not crash the system server. 599 Log.e(LOGTAG, "error starting relro file creator for abi " + abi, t); 600 crashHandler.run(); 601 } 602 } 603 604 private static class RelroFileCreator { 605 // Called in an unprivileged child process to create the relro file. 606 public static void main(String[] args) { 607 boolean result = false; 608 boolean is64Bit = VMRuntime.getRuntime().is64Bit(); 609 try{ 610 if (args.length != 2 || args[0] == null || args[1] == null) { 611 Log.e(LOGTAG, "Invalid RelroFileCreator args: " + Arrays.toString(args)); 612 return; 613 } 614 Log.v(LOGTAG, "RelroFileCreator (64bit = " + is64Bit + "), " + 615 " 32-bit lib: " + args[0] + ", 64-bit lib: " + args[1]); 616 if (!sAddressSpaceReserved) { 617 Log.e(LOGTAG, "can't create relro file; address space not reserved"); 618 return; 619 } 620 result = nativeCreateRelroFile(args[0] /* path32 */, 621 args[1] /* path64 */, 622 CHROMIUM_WEBVIEW_NATIVE_RELRO_32, 623 CHROMIUM_WEBVIEW_NATIVE_RELRO_64); 624 if (result && DEBUG) Log.v(LOGTAG, "created relro file"); 625 } finally { 626 // We must do our best to always notify the update service, even if something fails. 627 try { 628 getUpdateService().notifyRelroCreationCompleted(); 629 } catch (RemoteException e) { 630 Log.e(LOGTAG, "error notifying update service", e); 631 } 632 633 if (!result) Log.e(LOGTAG, "failed to create relro file"); 634 635 // Must explicitly exit or else this process will just sit around after we return. 636 System.exit(0); 637 } 638 } 639 } 640 641 // Assumes that we have waited for relro creation 642 private static int loadNativeLibrary(ClassLoader clazzLoader, PackageInfo packageInfo) { 643 if (!sAddressSpaceReserved) { 644 Log.e(LOGTAG, "can't load with relro file; address space not reserved"); 645 return LIBLOAD_ADDRESS_SPACE_NOT_RESERVED; 646 } 647 648 String[] args = getWebViewNativeLibraryPaths(packageInfo); 649 int result = nativeLoadWithRelroFile(args[0] /* path32 */, 650 args[1] /* path64 */, 651 CHROMIUM_WEBVIEW_NATIVE_RELRO_32, 652 CHROMIUM_WEBVIEW_NATIVE_RELRO_64, 653 clazzLoader); 654 if (result != LIBLOAD_SUCCESS) { 655 Log.w(LOGTAG, "failed to load with relro file, proceeding without"); 656 } else if (DEBUG) { 657 Log.v(LOGTAG, "loaded with relro file"); 658 } 659 return result; 660 } 661 662 private static String WEBVIEW_UPDATE_SERVICE_NAME = "webviewupdate"; 663 664 /** @hide */ 665 public static IWebViewUpdateService getUpdateService() { 666 return IWebViewUpdateService.Stub.asInterface( 667 ServiceManager.getService(WEBVIEW_UPDATE_SERVICE_NAME)); 668 } 669 670 private static native boolean nativeReserveAddressSpace(long addressSpaceToReserve); 671 private static native boolean nativeCreateRelroFile(String lib32, String lib64, 672 String relro32, String relro64); 673 private static native int nativeLoadWithRelroFile(String lib32, String lib64, 674 String relro32, String relro64, 675 ClassLoader clazzLoader); 676} 677