Strong zip protector

Author: REAndroid

src/main/java/com/reandroid/apkeditor/protect/ProtectedFileWriter.java

@@ -0,0 +1,84 @@
+/*
+ *  Copyright (C) 2022 github.com/REAndroid
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.reandroid.apkeditor.protect;
+
+import com.reandroid.apk.ApkModule;
+import com.reandroid.apk.DexFileInputSource;
+import com.reandroid.app.AndroidManifest;
+import com.reandroid.archive.block.CentralEntryHeader;
+import com.reandroid.archive.block.DataDescriptor;
+import com.reandroid.archive.block.LocalFileHeader;
+import com.reandroid.archive.writer.ApkFileWriter;
+import com.reandroid.archive.writer.HeaderInterceptor;
+import com.reandroid.arsc.chunk.TableBlock;
+
+import java.io.File;
+import java.io.IOException;
+import java.util.HashSet;
+import java.util.Set;
+
+public class ProtectedFileWriter implements HeaderInterceptor {
+
+    private final ApkModule apkModule;
+    private final File file;
+    private final Set<String> mProtectedFiles;
+
+    public ProtectedFileWriter(ApkModule apkModule, File file) {
+        this.apkModule = apkModule;
+        this.file = file;
+        this.mProtectedFiles = new HashSet<>();
+    }
+
+    public void write() throws IOException {
+        ApkFileWriter writer = apkModule.createApkFileWriter(this.file);
+        writer.getInterceptorChain().setHeaderInterceptor(this);
+        writer.write();
+        writer.close();
+    }
+
+    @Override
+    public void onWriteLfh(LocalFileHeader lfh) {
+        String name = lfh.getFileName();
+        if (needsProtection(name)) {
+            mProtectedFiles.add(name);
+            lfh.getGeneralPurposeFlag().setEncryption(true);
+        }
+    }
+
+    @Override
+    public void onWriteDD(DataDescriptor dataDescriptor) {
+    }
+
+    @Override
+    public void onWriteCeh(CentralEntryHeader ceh) {
+        if (mProtectedFiles.contains(ceh.getFileName())) {
+            ceh.getGeneralPurposeFlag().setEncryption(true);
+        }
+    }
+
+    private boolean needsProtection(String name) {
+        if (AndroidManifest.FILE_NAME.equals(name)) {
+            return true;
+        }
+        if (TableBlock.FILE_NAME.equals(name)) {
+            return true;
+        }
+        if (name.startsWith("lib/") && name.endsWith(".so")) {
+            return true;
+        }
+        return DexFileInputSource.isDexName(name);
+    }
+}

src/main/java/com/reandroid/apkeditor/protect/Protector.java

@@ -61,7 +61,12 @@ public void runCommand() throws IOException {
         new TableConfuser(this).confuse();
         module.getTableBlock().refresh();
         logMessage("Writing apk ...");
-        module.writeApk(options.outputFile);
+        if (!options.skipZip) {
+            logMessage("Protecting zip structure");
+            new ProtectedFileWriter(module, options.outputFile).write();
+        } else {
+            module.writeApk(options.outputFile);
+        }
         module.close();
         logMessage("Saved to: " + options.outputFile);
     }

src/main/java/com/reandroid/apkeditor/protect/ProtectorOptions.java

@@ -35,6 +35,9 @@ public class ProtectorOptions extends Options {
     @OptionArg(name = "-skip-manifest", flag = true, description = "protect_skip_manifest")
     public boolean skipManifest;
 
+    @OptionArg(name = "-skip-zip", flag = true, description = "protect_skip_zip")
+    public boolean skipZip;
+
     @OptionArg(name = "-keep-type", description = "protect_keep_type")
     public final Set<String> keepTypes = new HashSet<>();
 

src/main/resources/strings/strings.properties

@@ -104,6 +104,7 @@ protect_description=Protects/Obfuscates apk resource files. Using unique obfusca
 protect_example_1=[Basic]\n  java -jar APKEditor.jar p -i path/input.apk -o path/output.apk
 protect_keep_type=Keep specific resource type names (e.g drawable), By default keeps only <font> resource type.\n *Can be multiple
 protect_skip_manifest=Do not protect manifest.
+protect_skip_zip=Do not protect zip structure.
 raw_dex=Copy raw dex files / skip smali.
 res_dir_name=Sets resource files root dir name. e.g. for obfuscation to move files from 'res/*' to 'r/*' or vice versa.
 refactor_description=Refactors obfuscated resource names