Android11应用自启动限制
大纲
- Android11应用自启动限制
- 分析
- 验证猜想:Android11 AOSP是否自带禁止三方应用监听`BOOT_COMPLETED`
- 方案
- 禁止执行非系统应用监听到`BOOT_COMPLETED`后的代码逻辑
- 在执行启动时判断其启动的广播接收器
- 一棍子打死方案(慎用)
- 补充!!!!!!!
分析
按理说三方应用应该收不到开机启动广播(后文会证实这个说法是假的),但是很神奇的是还是有应用能自启动,体现为比如秋秋,启动后通过ps命令能看到其进程存活,但是静置后进程会启动失败,从而导致被清理
07-18 05:59:02.132367 938 967 I ActivityManager: Start proc 1930:com.tencent.mobileqq:MSF/u0a110 for broadcast {com.tencent.mobileqq/com.tencent.mobileqq.msf.core.NetConnInfoCenter}
log如上
参照这篇博客Android系统层面限制应用开机自启动详解,此时通过Android Studio查看其apk的manifest,其NetConnInfoCenter
内容如下
可以看到其监听了开机广播外,还监听了各种各样的广播,比如TIMEZONE_CHANGED
,看起来是时区变换的广播,这边尝试了一下在没有启动秋秋的情况下,去切换时区,果然打印了启动秋秋的log,虽然没有启动成功,但是之前在这个项目中,自己遇到过秋秋启动成功的情况,所以还是要处理
<receiver
android:name="com.tencent.mobileqq.msf.core.NetConnInfoCenter"
android:exported="false"
android:process=":MSF">
<intent-filter
android:priority="2147483647">
<action
android:name="android.intent.action.BOOT_COMPLETED" />
</intent-filter>
<intent-filter>
<action
android:name="android.intent.action.MY_PACKAGE_REPLACED" />
</intent-filter>
<intent-filter>
<action
android:name="android.net.conn.CONNECTIVITY_CHANGE" />
</intent-filter>
<intent-filter>
<action
android:name="android.intent.action.TIME_SET" />
</intent-filter>
<intent-filter>
<action
android:name="android.intent.action.TIMEZONE_CHANGED" />
</intent-filter>
<intent-filter>
<action
android:name="com.tencent.mobileqq.rdm.report" />
</intent-filter>
<intent-filter>
<action
android:name="com.tencent.mobileqq.msf.receiveofflinepush" />
</intent-filter>
<intent-filter>
<action
android:name="com.tencent.mobileqq.msf.offlinepushclearall" />
</intent-filter>
<intent-filter>
<action
android:name="com.tencent.mobileqq.msf.receiveofflinepushav" />
</intent-filter>
<intent-filter>
<action
android:name="com.tencent.mobileqq.msf.offlinepushclearallav" />
</intent-filter>
<intent-filter>
<action
android:name="com.tencent.mobileqq.msf.startmsf" />
</intent-filter>
<intent-filter>
<action
android:name="android.intent.action.MEDIA_BAD_REMOVAL" />
<action
android:name="android.intent.action.MEDIA_EJECT" />
<action
android:name="android.intent.action.MEDIA_MOUNTED" />
<action
android:name="android.intent.action.MEDIA_REMOVED" />
<action
android:name="android.intent.action.MEDIA_SCANNER_FINISHED" />
<action
android:name="android.intent.action.MEDIA_SCANNER_STARTED" />
<action
android:name="android.intent.action.MEDIA_SHARED" />
<action
android:name="android.intent.action.MEDIA_UNMOUNTED" />
<data
android:scheme="file" />
</intent-filter>
<intent-filter>
<action
android:name="android.net.wifi.WIFI_STATE_CHANGED" />
</intent-filter>
</receiver>
验证猜想:Android11 AOSP是否自带禁止三方应用监听BOOT_COMPLETED
因为前面提到Android11三方应用到底能不能监听开机广播,这边写了个demo,仅监听BOOT_COMPLETED
,重启后验证,进程会正常被创建,所以Android11并没有原生的禁止三方监听BOOT_COMPLETED
的策略。至少AOSP没有,国内手机带此功能是手机厂商自己实现的
public class BootReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {
if (Intent.ACTION_BOOT_COMPLETED.equals(intent.getAction())) {
Intent mIntent = new Intent(context, MainActivity.class);
mIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(mIntent); // 启动你的应用程序
}
}
}
<uses-permission
android:name="android.permission.RECEIVE_BOOT_COMPLETED" />
<receiver android:name=".BootReceiver"
android:exported="false">
<intent-filter>
<action android:name="android.intent.action.BOOT_COMPLETED" />
</intent-filter>
</receiver>
结论:Android11上普通三方应用是可以接收到开机广播的,此时如果应用去自启动,后台会有进程存活,因此需要做处理
方案
禁止执行非系统应用监听到BOOT_COMPLETED
后的代码逻辑
在处理广播的地方 过滤掉所有的三方应用,并预留白名单
在AMS的broadcastIntentLocked
方法中
diff --git a/frameworks/base/services/core/java/com/android/server/am/ActivityManagerService.java b/frameworks/base/services/core/java/com/android/server/am/ActivityManagerService.java
index f26ae929ef..6b906ced4f 100644
--- a/frameworks/base/services/core/java/com/android/server/am/ActivityManagerService.java
+++ b/frameworks/base/services/core/java/com/android/server/am/ActivityManagerService.java
@@ -16736,7 +16736,30 @@ public class ActivityManagerService extends IActivityManager.Stub
final int broadcastIntentLocked(ProcessRecord callerApp, String callerPackage,
@Nullable String callerFeatureId, Intent intent, String resolvedType,
IIntentReceiver resultTo, int resultCode, String resultData,
Bundle resultExtras, String[] requiredPermissions, int appOp, Bundle bOptions,
boolean ordered, boolean sticky, int callingPid, int callingUid, int realCallingUid,
int realCallingPid, int userId, boolean allowBackgroundActivityStarts,
@Nullable int[] broadcastWhitelist) {
...
if (receivers != null) {
String skipPackages[] = null;
if (Intent.ACTION_PACKAGE_ADDED.equals(intent.getAction())
|| Intent.ACTION_PACKAGE_RESTARTED.equals(intent.getAction())
|| Intent.ACTION_PACKAGE_DATA_CLEARED.equals(intent.getAction())) {
Uri data = intent.getData();
if (data != null) {
String pkgName = data.getSchemeSpecificPart();
if (pkgName != null) {
skipPackages = new String[] { pkgName };
}
}
} else if (Intent.ACTION_EXTERNAL_APPLICATIONS_AVAILABLE.equals(intent.getAction())) {
skipPackages = intent.getStringArrayExtra(Intent.EXTRA_CHANGED_PACKAGE_LIST);
- }
+ // add by xumaoxin start
+ } else if (Intent.ACTION_BOOT_COMPLETED.equals(intent.getAction())) {
+ //Resources res = mContext.getResources();
+ //String[] blacklist = res.getStringArray(com.android.internal.R.array.blacklist_boot_receiver);
+ List<String> skipList = new ArrayList<>();
+ Set<String> whitelist = new ArraySet<>();
+ whitelist.add("com.example.test11");
+
+ for (int i = 0, j = receivers.size(); i < j; i++) {
+ ResolveInfo curt = (ResolveInfo) receivers.get(i);
+ String curPkgName = curt.activityInfo.packageName;
+ if ((curt.activityInfo.applicationInfo.flags & ApplicationInfo.FLAG_SYSTEM) != 0) {
+ //Slog.i("ActivityManager", "xumaoxin: " + curPkgName + " is system app, allow!");
+ } else if (!whitelist.contains(curPkgName)) {
+ Slog.i("ActivityManager", "xumaoxin: " + curPkgName + " is not system app and not whitelist, not allow!");
+ skipList.add(curPkgName);
+ }else {
+ Slog.i("ActivityManager", "xumaoxin: " + curPkgName + " is not system app but is whitelist, allow!");
+ }
+ }
+ skipPackages = skipList.toArray(new String[0]);
+ Slog.i("ActivityManager", "xumaoxin: skipPackages= " + Arrays.toString(skipPackages));
+ //add by xumaoxin end
+ }
if (skipPackages != null && (skipPackages.length > 0)) {
for (String skipPackage : skipPackages) {
if (skipPackage != null) {
判断是不是系统应用
curt.activityInfo.applicationInfo.flags & ApplicationInfo.FLAG_SYSTEM) != 0 //是系统应用
注意:此处只能禁止执行skipPackages中的应用去监听到
BOOT_COMPLETED
后的执行逻辑,如果应用只做了这一个监听来自启,比如我前面写的demo,这样就足够了,但是国内三方app一般会想方设法地自启动,这边验证了秋秋还是会启动起来,会有进程存在,继续处理。
在执行启动时判断其启动的广播接收器
注意:同样需要处理秋秋的同学请一定看到最后,这一节的方案不完善
基于log
ActivityManager: Start proc 2962:com.tencent.mobileqq:MSF/u0a112 for broadcast {com.tencent.mobileqq/com.tencent.mobileqq.msf.core.NetConnInfoCenter}
这里秋秋自己的广播接收器叫com.tencent.mobileqq/com.tencent.mobileqq.msf.core.NetConnInfoCenter
,我们先找到这行log打印的地方
ActivityManager为tag的,在server/am下去grep就好,找到其文件
frameworks\base\services\core\java\com\android\server\am\ProcessList.java
boolean handleProcessStartedLocked(ProcessRecord app, int pid, boolean usingWrapper,
long expectedStartSeq, boolean procAttached) {
mPendingStarts.remove(expectedStartSeq);
final String reason = isProcStartValidLocked(app, expectedStartSeq);
if (reason != null) {
Slog.w(TAG_PROCESSES, app + " start not valid, killing pid=" +
pid
+ ", " + reason);
app.pendingStart = false;
killProcessQuiet(pid);
Process.killProcessGroup(app.uid, app.pid);
noteAppKill(app, ApplicationExitInfo.REASON_OTHER,
ApplicationExitInfo.SUBREASON_INVALID_START, reason);
return false;
}
......
StringBuilder buf = mStringBuilder;
buf.setLength(0);
buf.append("Start proc ");
buf.append(pid);
buf.append(':');
buf.append(app.processName);
buf.append('/');
UserHandle.formatUid(buf, app.startUid);
if (app.isolatedEntryPoint != null) {
buf.append(" [");
buf.append(app.isolatedEntryPoint);
buf.append("]");
}
buf.append(" for ");
buf.append(app.hostingRecord.getType());
if (app.hostingRecord.getName() != null) {
buf.append(" ");
buf.append(app.hostingRecord.getName());
}
能看到buf.append("Start proc ");
这里开始的buf记录和我们log是一样的,所以后面的app.hostingRecord.getType()
对应log中的广播接收器broadcast
,而app.hostingRecord.getName()
对应log中的{com.tencent.mobileqq/com.tencent.mobileqq.msf.core.NetConnInfoCenter}
那就好处理了,判断其name,如果是NetConnInfoCenter
,那就不允许启动。
代码往前,能看到原生有一个退出的逻辑,通过final String reason = isProcStartValidLocked(app, expectedStartSeq);
赋值
在isProcStartValidLocked
方法中加入秋秋的判断,返回一个reason,这样此次启动能通过原生的逻辑进行拦截,比较安全
diff --git a/frameworks/base/services/core/java/com/android/server/am/ProcessList.java b/frameworks/base/services/core/java/com/android/server/am/ProcessList.java
index 9d4deb4d5b..271f99138f 100644
--- a/frameworks/base/services/core/java/com/android/server/am/ProcessList.java
+++ b/frameworks/base/services/core/java/com/android/server/am/ProcessList.java
@@ -2462,6 +2462,14 @@ public final class ProcessList {
@GuardedBy("mService")
private String isProcStartValidLocked(ProcessRecord app, long expectedStartSeq) {
StringBuilder sb = null;
+ if (app.hostingRecord.getName() != null) {
+ String name = app.hostingRecord.getName();
+ Slog.i("ActivityManager", "xumaoxin: broadcast= " + name);
+ if (name.contains("NetConnInfoCenter")) {
+ if (sb == null) sb = new StringBuilder();
+ sb.append("dont allow qq auto start");
+ }
+ }
if (app.killedByAm) {
if (sb == null) sb = new StringBuilder();
sb.append("killedByAm=true;");
编译push验证,秋秋在设备重启后不会再重启,会被拦截
抑制秋秋自启动成功!同时不会影响用户手动点击图标等方式的启动
应用多了可以写成白名单,并配置到xml中
注意:此方案的弊端就是只能对特定的应用单独加判断逻辑,不能适用于所有应用
一棍子打死方案(慎用)
观察三方应用是否都是通过broadcast
类型进行自启动的,能否判断type
是否是broadcast
来进行通用过滤?风险就是这样一来一棍子打死了,等于不再允许三方应用通过广播方式进行启动
diff --git a/frameworks/base/services/core/java/com/android/server/am/ProcessList.java b/frameworks/base/services/core/java/com/android/server/am/ProcessList.java
index 9d4deb4d5b..03a4c1ddb2 100644
--- a/frameworks/base/services/core/java/com/android/server/am/ProcessList.java
+++ b/frameworks/base/services/core/java/com/android/server/am/ProcessList.java
@@ -2462,6 +2462,19 @@ public final class ProcessList {
@GuardedBy("mService")
private String isProcStartValidLocked(ProcessRecord app, long expectedStartSeq) {
StringBuilder sb = null;
+ /*if (app.hostingRecord.getName() != null) {
+ String name = app.hostingRecord.getName();
+ Slog.i("ActivityManager", "xumaoxin: broadcast= " + name);
+ if (name.contains("NetConnInfoCenter")) {
+ if (sb == null) sb = new StringBuilder();
+ sb.append("dont allow qq auto start");
+ }
+ }*/
+ if (((app.info.flags & ApplicationInfo.FLAG_SYSTEM) == 0) && "broadcast".equals(app.hostingRecord.getType())) {
+ String name = app.hostingRecord.getName();
+ if (sb == null) sb = new StringBuilder();
+ sb.append("dont allow thirdapp auto start by broadcast: " + name);
+ }
if (app.killedByAm) {
if (sb == null) sb = new StringBuilder();
sb.append("killedByAm=true;");
编译后验证秋秋确实是没有问题,主要不确定其他的广播场景会不会被拦截下来,毕竟一棍子打死的办法杀伤面有点大
尽量还是使用第一种+第二种,不让三方应用执行开机广播逻辑+特殊应用特殊过滤。第三种方案慎用!
补充!!!!!!!
对于秋秋前面通过广播想启动的只是其一个子进程,在登陆的时候会用到,如果一直不让其自动启动,会导致登陆超时。
所以还需要加入判断,启动的时候秋秋主进程是否存活,如果存活,我们认为秋秋不是在后台想自启动,而是通过正常途径启动子进程。
而进行是否存活的判断调用较频繁,而我们的系统应用不需要进行此判断,所以调用前再加入是否系统应用的判断。实现代码diff如下
--- a/frameworks/base/services/core/java/com/android/server/am/ProcessList.java
+++ b/frameworks/base/services/core/java/com/android/server/am/ProcessList.java
@@ -2459,14 +2459,27 @@ public final class ProcessList {
return success ? app : null;
}
+ public boolean isAppRunning(String packageName) {
+ List<ActivityManager.RunningAppProcessInfo> runningProcesses = mService.getRunningAppProcesses();
+ if (runningProcesses.size() > 0) {
+ for (ActivityManager.RunningAppProcessInfo info : runningProcesses) {
+ if (info.processName.equals(packageName)) {
+ return true;
+ }
+ }
+ }
+ return false;
+ }
+
@GuardedBy("mService")
private String isProcStartValidLocked(ProcessRecord app, long expectedStartSeq) {
StringBuilder sb = null;
// add by sprocomm start
- if (app.hostingRecord.getName() != null) {
+ //非系统应用执行if中的逻辑
+ if (((app.info.flags & ApplicationInfo.FLAG_SYSTEM) == 0) && app.hostingRecord.getName() != null) {
String name = app.hostingRecord.getName();
- Slog.i("ActivityManager", "xumaoxin: broadcast= " + name);
- if (name.contains("NetConnInfoCenter")) {
+ //秋秋是否存活,这个包名,可以动态到白名单中,和NetConnInfoCenter这个组件名放一起
+ boolean isRunning = isAppRunning("com.tencent.mobileqq");
+ Slog.i("ActivityManager", "xumaoxin: com.tencent.mobileqq isRunning= "+ isRunning + ", broadcast= " + name);
+ if (!isRunning && name.contains("NetConnInfoCenter")) {
if (sb == null) sb = new StringBuilder();
sb.append("dont allow qq auto start");
}