Fix stub app loading on older Android versions

app/shared/src/main/java/com/topjohnwu/magisk/utils/DynamicClassLoader.java

@@ -9,10 +9,8 @@ import dalvik.system.BaseDexClassLoader;
 
 public class DynamicClassLoader extends BaseDexClassLoader {
 
-    private static final ClassLoader base = Object.class.getClassLoader();
-
     public DynamicClassLoader(File apk) {
-        this(apk, base);
+        this(apk, getSystemClassLoader());
     }
 
     public DynamicClassLoader(File apk, ClassLoader parent) {
@@ -29,7 +27,7 @@ public class DynamicClassLoader extends BaseDexClassLoader {
 
         try {
             // Then check boot classpath
-            return base.loadClass(name);
+            return getSystemClassLoader().loadClass(name);
         } catch (ClassNotFoundException ignored) {
             try {
                 // Next try current dex
@@ -47,7 +45,7 @@ public class DynamicClassLoader extends BaseDexClassLoader {
 
     @Override
     public URL getResource(String name) {
-        URL resource = base.getResource(name);
+        URL resource = getSystemClassLoader().getResource(name);
         if (resource != null)
             return resource;
         resource = findResource(name);
@@ -59,7 +57,7 @@ public class DynamicClassLoader extends BaseDexClassLoader {
 
     @Override
     public Enumeration<URL> getResources(String name) throws IOException {
-        return new CompoundEnumeration<>(base.getResources(name),
+        return new CompoundEnumeration<>(getSystemClassLoader().getResources(name),
                 findResources(name), getParent().getResources(name));
     }
 }

app/src/main/java/com/topjohnwu/magisk/core/Hacks.kt

@@ -4,6 +4,7 @@ package com.topjohnwu.magisk.core
 
 import android.content.ComponentName
 import android.content.Context
+import android.content.ContextWrapper
 import android.content.Intent
 import android.content.res.AssetManager
 import android.content.res.Configuration
@@ -13,16 +14,12 @@ import com.topjohnwu.magisk.R
 import com.topjohnwu.magisk.StubApk
 import com.topjohnwu.magisk.core.di.AppContext
 import com.topjohnwu.magisk.core.utils.syncLocale
+import com.topjohnwu.magisk.ktx.unwrap
 
 lateinit var AppApkPath: String
 
 fun Resources.addAssetPath(path: String) = StubApk.addAssetPath(this, path)
 
-fun Context.patch(): Context {
-    resources.patch()
-    return this
-}
-
 fun Resources.patch(): Resources {
     if (isRunningAsStub)
         addAssetPath(AppApkPath)
@@ -30,6 +27,21 @@ fun Resources.patch(): Resources {
     return this
 }
 
+fun Context.patch(): Context {
+    unwrap().resources.patch()
+    return this
+}
+
+// Wrapping is only necessary for ContextThemeWrapper to support configuration overrides
+fun Context.wrap(): Context {
+    patch()
+    return object : ContextWrapper(this) {
+        override fun createConfigurationContext(config: Configuration): Context {
+            return super.createConfigurationContext(config).wrap()
+        }
+    }
+}
+
 fun createNewResources(): Resources {
     val asset = AssetManager::class.java.newInstance()
     val config = Configuration(AppContext.resources.configuration)

app/src/main/java/com/topjohnwu/magisk/core/base/BaseActivity.kt

@@ -5,7 +5,6 @@ import android.Manifest.permission.WRITE_EXTERNAL_STORAGE
 import android.content.ActivityNotFoundException
 import android.content.Context
 import android.content.Intent
-import android.content.res.Configuration
 import android.net.Uri
 import android.os.Build
 import android.os.Bundle
@@ -18,9 +17,9 @@ import androidx.annotation.WorkerThread
 import androidx.appcompat.app.AppCompatActivity
 import com.topjohnwu.magisk.R
 import com.topjohnwu.magisk.core.isRunningAsStub
-import com.topjohnwu.magisk.core.patch
 import com.topjohnwu.magisk.core.utils.RequestInstall
 import com.topjohnwu.magisk.core.utils.UninstallPackage
+import com.topjohnwu.magisk.core.wrap
 import com.topjohnwu.magisk.ktx.reflectField
 import com.topjohnwu.magisk.utils.Utils
 import java.util.concurrent.CountDownLatch
@@ -56,11 +55,7 @@ abstract class BaseActivity : AppCompatActivity() {
     }
 
     override fun attachBaseContext(base: Context) {
-        super.attachBaseContext(base.patch())
-    }
-
-    override fun createConfigurationContext(config: Configuration): Context {
-        return super.createConfigurationContext(config).patch()
+        super.attachBaseContext(base.wrap())
     }
 
     override fun onCreate(savedInstanceState: Bundle?) {

buildSrc/src/main/java/Setup.kt

@@ -12,12 +12,12 @@ import org.gradle.api.tasks.Sync
 import org.gradle.kotlin.dsl.filter
 import org.gradle.kotlin.dsl.named
 import org.jetbrains.kotlin.gradle.dsl.KotlinJvmOptions
-import java.io.*
+import java.io.ByteArrayInputStream
+import java.io.ByteArrayOutputStream
+import java.io.File
+import java.io.PrintStream
 import java.util.*
-import java.util.zip.Deflater
-import java.util.zip.ZipEntry
-import java.util.zip.ZipFile
-import java.util.zip.ZipOutputStream
+import java.util.zip.*
 
 private fun Project.androidBase(configure: Action<BaseExtension>) =
     extensions.configure("android", configure)
@@ -219,22 +219,23 @@ fun Project.setupStub() {
                     commandLine(aapt, "optimize", "-o", apkTmp, "--collapse-resource-names", apk)
                 }
 
-                val buffer = ByteArrayOutputStream(apk.length().toInt())
-                val newApk = ZipOutputStream(FileOutputStream(apk))
-                ZipFile(apkTmp).use {
-                    newApk.use { new ->
-                        new.setLevel(Deflater.BEST_COMPRESSION)
-                        new.putNextEntry(ZipEntry("AndroidManifest.xml"))
-                        it.getInputStream(it.getEntry("AndroidManifest.xml")).transferTo(new)
-                        new.closeEntry()
-                        new.finish()
+                val buffer = ByteArrayOutputStream()
+                apkTmp.inputStream().use {
+                    object : GZIPOutputStream(buffer) {
+                        init {
+                            def.setLevel(Deflater.BEST_COMPRESSION)
+                        }
+                    }.use { o ->
+                        it.transferTo(o)
                     }
-                    ZipOutputStream(buffer).use { arsc ->
-                        arsc.setLevel(Deflater.BEST_COMPRESSION)
-                        arsc.putNextEntry(ZipEntry("resources.arsc"))
-                        it.getInputStream(it.getEntry("resources.arsc")).transferTo(arsc)
-                        arsc.closeEntry()
-                        arsc.finish()
+                }
+                ZipFile(apkTmp).use { o ->
+                    ZipOutputStream(apk.outputStream()).use { n ->
+                        n.setLevel(Deflater.BEST_COMPRESSION)
+                        n.putNextEntry(ZipEntry("AndroidManifest.xml"))
+                        o.getInputStream(o.getEntry("AndroidManifest.xml")).transferTo(n)
+                        n.closeEntry()
+                        n.finish()
                     }
                 }
                 apkTmp.delete()

stub/src/main/java/com/topjohnwu/magisk/ClassLoaders.java

@@ -131,7 +131,7 @@ class StubClassLoader extends ClassLoader {
 class DelegateClassLoader extends ClassLoader {
 
     DelegateClassLoader() {
-        super(null);
+        super();
     }
 
     @Override

stub/src/main/java/com/topjohnwu/magisk/DownloadActivity.java

@@ -34,6 +34,7 @@ import java.io.File;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.OutputStream;
+import java.util.zip.GZIPInputStream;
 
 import javax.crypto.Cipher;
 import javax.crypto.CipherInputStream;
@@ -95,6 +96,12 @@ public class DownloadActivity extends Activity {
         }
     }
 
+    @Override
+    public void finish() {
+        super.finish();
+        Runtime.getRuntime().exit(0);
+    }
+
     private void error(Throwable e) {
         Log.e(getClass().getSimpleName(), "", e);
         finish();
@@ -154,7 +161,8 @@ public class DownloadActivity extends Activity {
         SecretKey key = new SecretKeySpec(Bytes.key(), "AES");
         IvParameterSpec iv = new IvParameterSpec(Bytes.iv());
         cipher.init(Cipher.DECRYPT_MODE, key, iv);
-        var is = new CipherInputStream(new ByteArrayInputStream(Bytes.res()), cipher);
+        var is = new GZIPInputStream(new CipherInputStream(
+                new ByteArrayInputStream(Bytes.res()), cipher));
         try (is; out) {
             APKInstall.transfer(is, out);
         }