Android 根据已装应用的签名限制其他应用安装

参考文章：https://blog.csdn.net/loongembedded/article/details/54090873
只有使用特定签名的apk才可以安装，其他任何apk都不能安装

最好是应用预装一个使用对应签名的应用

需要修改的文件有以下几个
/frameworks/base/services/core/java/com/android/server/pm/PackageManagerService.java

/frameworks/base/core/java/android/content/pm/PackageManager.java

/packages/apps/PackageInstaller/src/com/android/packageinstaller/InstallAppProgress.java

/packages/apps/PackageInstaller/res/values/strings.xml

1 PackageManagerService.java

/frameworks/base/services/core/java/com/android/server/pm/PackageManagerService.java
添加getSignaturesByPackage()方法

//add start
       private Signature[] getSignaturesByPackage(){
           Signature[] signatures = null;
           //已签名的已安装应用包名，与该应用签名不同的应用无法安装
           String packageName = "com.xxxx.xxxxx";
           PackageSetting ps = mSettings.mPackages.get(packageName);
           if (ps != null) {
                PackageParser.Package pkg = ps.pkg;
                if (pkg == null) {
                    pkg = new PackageParser.Package(packageName);
                    pkg.applicationInfo.packageName = packageName;
                    pkg.applicationInfo.flags = ps.pkgFlags | ApplicationInfo.FLAG_IS_DATA_ONLY;
                    pkg.applicationInfo.publicSourceDir = ps.resourcePathString;
                    pkg.applicationInfo.sourceDir = ps.codePathString;
                    pkg.applicationInfo.dataDir = getDataPathForPackage(packageName, 0).getPath();
                   // pkg.applicationInfo.nativeLibraryDir = ps.nativeLibraryPathString;
                }
 
                PackageInfo packageInfo2 = generatePackageInfo(pkg, PackageManager.GET_SIGNATURES, UserHandle.getCallingUserId());
 
                if(packageInfo2 != null){
                    signatures = packageInfo2.signatures;
                }
           }
           mIsInstallApkFlag = false;
           return signatures;
       }
     //add end

在scanPackageLI方法下加入如下代码

private PackageParser.Package scanPackageLI(PackageParser.Package pkg, int parseFlags , int scanFlags, long currentTime, UserHandle user) throws PackageManagerException {
          boolean success = false;
          //add start  
          //获得安装的应用的签名信息
           Signature[] originalSignatures = getSignaturesByPackage();
           if (originalSignatures != null) {
               if (compareSignatures(originalSignatures, pkg.mSignatures) != PackageManager.SIGNATURE_MATCH) {
                   int mLastScanError = PackageManager.INSTALL_FAILED_INVALID_SIGNATURES;
                    throw new PackageManagerException(mLastScanError,
                              "禁止安装，签名不符");
               }
          }
          //add end
         ...

同时要import缺少的类。

2 PackageManager.java

/frameworks/base/core/java/android/content/pm/PackageManager.java
加入错误代码 INSTALL_FAILED_INVALID_SIGNATURES

     /** 
      * cyh add
      */
      public static final int INSTALL_FAILED_INVALID_SIGNATURES = -27;

3 InstallAppProgress.java

/packages/apps/PackageInstaller/src/com/android/packageinstaller/InstallAppProgress.java
加入针对添加的错误代码的处理

private Handler mHandler = new Handler() {  
        public void handleMessage(Message msg) {  
            switch (msg.what) {  
        ...
            //add start
                     } else if (msg.arg1 ==  PackageManager.INSTALL_FAILED_INVALID_SIGNATURES){
                       // Generic error handling for all other error codes.  
                        centerTextDrawable.setLevel(1);
                        centerExplanationLabel = getExplanationFromErrorCode(msg.arg1);
                        //centerTextLabel = R.string.install_failed_invalid_signature;  
                        centerTextLabel = R.string.install_failed_invalid_signature;
                        mLaunchButton.setVisibility(View.INVISIBLE);
                       //add end
                     }  else {
                         // Generic error handling for all other error codes.
                         centerTextDrawable.setLevel(1);
                         centerExplanationLabel = getExplanationFromErrorCode(msg.arg1);
                         centerTextLabel = R.string.install_failed;
                         mLaunchButton.setVisibility(View.INVISIBLE);
                     }

4 strings.xml

/packages/apps/PackageInstaller/res/values/string.xml
添加错误信息install_failed_invalid_signature

<string name="install_failed_invalid_signature">禁止安装，签名不符</string>