Android 获取应用签名

本文主要讲下在android中如何获取应用签名. 也方便平时用来区分一个应用是不是原包应用.

1: 通过PackageManager获取签名信息

首先,通过packageManager获取到指定应用的PackageInfo. 这里需要传入的flag是PackageManager.GET_SIGNATURES

/**
 * {@link PackageInfo} flag: return information about the
 * signatures included in the package.
 *
 * @deprecated use {@code GET_SIGNING_CERTIFICATES} instead
 */
@Deprecated
public static final int GET_SIGNATURES          = 0x00000040;

PackageManager pm = getPackageManager();
List<ApplicationInfo> applications = pm.getInstalledApplications(PackageManager.GET_META_DATA);
for (ApplicationInfo applicationInfo : applications) {
    try {
        PackageInfo packageInfo = packageManager.getPackageInfo(applicationInfo.packageName, PackageManager.GET_SIGNATURES);
		Signature[] signs = packageInfo.signatures;
    } catch (PackageManager.NameNotFoundException e) {
        e.printStackTrace();
    }
}

2: 获取SHA1

public class ShaUtils {
    public static String getSHA1(byte[] sig) {
        final char[] hexArray = "0123456789ABCDEF".toCharArray();
        try {
            MessageDigest md = MessageDigest.getInstance("SHA1");
            byte[] digest = md.digest(sig);
            char[] hexChars = new char[digest.length * 2];
            for (int j = 0; j < digest.length; j++) {
                int v = digest[j] & 0xFF;
                hexChars[j * 2] = hexArray[v >>> 4];
                hexChars[j * 2 + 1] = hexArray[v & 0x0F];
            }
            return new String(hexChars);
        } catch (Throwable e) {
            e.printStackTrace();
        }
        return "";
    }

}

下面是整理的一个小demo,展示当前设备的应用列表以及应用签名,包名,icon信息.

创建mainacitity

public class MainActivity extends AppCompatActivity {
    private GridView gridView;
    private ApkAdapter apkAdapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        gridView = findViewById(R.id.grid_sign);
        PackageManager packageManager = getPackageManager();
        List<ApplicationInfo> installedApplications = packageManager.getInstalledApplications(PackageManager.GET_META_DATA);
        apkAdapter = new ApkAdapter(installedApplications, this);
        gridView.setAdapter(apkAdapter);
    }


}

acitivity布局如下:

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <GridView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:numColumns="1"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        android:id="@+id/grid_sign"
        />
</androidx.constraintlayout.widget.ConstraintLayout>

ApkAdapter代码如下:

public class ApkAdapter extends BaseAdapter {
    private List<ApplicationInfo> list;
    private Context context;
    private PackageManager packageManager;

    public ApkAdapter(List<ApplicationInfo> list, Context context) {
        this.list = list;
        this.context = context;
        packageManager = context.getPackageManager();
    }

    @Override
    public int getCount() {
        return list.size();
    }

    @Override
    public Object getItem(int position) {
        return list.get(position);
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public View getView(int position, View view, ViewGroup parent) {
        if (view == null) {
            view = LayoutInflater.from(context).inflate(R.layout.item_apk, parent, false);
        }
        ApplicationInfo applicationInfo = list.get(position);
        ImageView icon = (ImageView) view.findViewById(R.id.item_icon);
        icon.setImageDrawable(applicationInfo.loadIcon(packageManager));
        TextView label = (TextView) view.findViewById(R.id.item_name);
        label.setText(applicationInfo.packageName);
        TextView sign = (TextView) view.findViewById(R.id.item_sign);
        StringBuilder stringBuilder = new StringBuilder();
        try {
            PackageInfo packageInfo = packageManager.getPackageInfo(applicationInfo.packageName, PackageManager.GET_SIGNATURES);
            Signature[] signs = packageInfo.signatures;
            for (Signature sig : signs) {
                String sha1 = ShaUtils.getSHA1(sig.toByteArray());
                stringBuilder.append("Signature: "+sha1+"\n");
                Log.d("Signature", "packageName = " + packageInfo.packageName + ", signature = " + sha1);
            }
            sign.setText(stringBuilder.toString());
        } catch (Throwable e) {
            Log.e("Signature", "getView: ", e);
        }
        return view;
    }
}

以及item的布局:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent"
    android:layout_height="100dp">
    <ImageView
        android:layout_width="80dp"
        android:layout_height="80dp"
        android:id="@+id/item_icon"
        android:layout_margin="10dp"
        />
   <RelativeLayout
       android:layout_width="match_parent"
       android:layout_height="wrap_content"
       android:layout_toRightOf="@+id/item_icon"
       android:layout_marginTop="10dp"
       android:layout_marginRight="10dp"
       >
       <TextView
           android:layout_width="wrap_content"
           android:layout_height="wrap_content"
           android:textSize="16sp"
           android:text="xxx"
           android:layout_alignParentTop="true"
           android:textColor="@color/black"
           android:id="@+id/item_name"
           />
       <TextView
           android:layout_width="wrap_content"
           android:layout_height="wrap_content"
           android:textColor="#ff0000"
           android:textSize="14sp"
           android:layout_alignParentBottom="true"
           android:layout_marginBottom="10dp"
           android:text="xxxxxxxxx"
           android:id="@+id/item_sign"
           />
   </RelativeLayout>

</RelativeLayout>

最后展示下效果图: