Add experimental COMPUTE_FRAMES option

ThexXTURBOXx · Dec 16, 2023 · 2f6e9e0 · 2f6e9e0
1 parent 9c9580b
commit 2f6e9e0
Show file tree

Hide file tree

Showing 3 changed files with 63 additions and 2 deletions.
diff --git a/dex-reader/src/main/java/com/googlecode/d2j/reader/DexFileReader.java b/dex-reader/src/main/java/com/googlecode/d2j/reader/DexFileReader.java
@@ -98,6 +98,13 @@ public class DexFileReader implements BaseDexFileReader {
 
     public static final int DONT_SANITIZE_NAMES = 1 << 9;
 
+    /**
+     * Instruct ASM to compute frames when generating class files,
+     * using {@link org.objectweb.asm.ClassWriter#COMPUTE_FRAMES}
+     * **EXPERIMENTAL CODE**
+     */
+    public static final int COMPUTE_FRAMES = 1 << 10;
+
     // private static final int REVERSE_ENDIAN_CONSTANT = 0x78563412;
 
     static final int DBG_END_SEQUENCE = 0x00;

diff --git a/dex-tools/src/main/java/com/googlecode/dex2jar/tools/Dex2jarCmd.java b/dex-tools/src/main/java/com/googlecode/dex2jar/tools/Dex2jarCmd.java
@@ -61,6 +61,10 @@ public static void main(String... args) {
     @Opt(opt = "dsn", longOpt = "dont-sanitize-names", hasArg = false, description = "do not replace '_' by '-'")
     private boolean dontSanitizeNames = false;
 
+    @Opt(opt = "cf", longOpt = "compute-frames", hasArg = false,
+            description = "instructs ASM to compute frames - experimental!")
+    private boolean computeFrames = false;
+
     @Override
     protected void doCommandLine() throws Exception {
         if (remainingArgs.length == 0) {
@@ -104,7 +108,8 @@ protected void doCommandLine() throws Exception {
             BaksmaliBaseDexExceptionHandler handler = notHandleException ? null : new BaksmaliBaseDexExceptionHandler();
             Dex2jar.from(reader).withExceptionHandler(handler).reUseReg(reuseReg).topoLogicalSort()
                     .skipDebug(!debugInfo).optimizeSynchronized(this.optmizeSynchronized).printIR(printIR)
-                    .noCode(noCode).skipExceptions(skipExceptions).dontSanitizeNames(dontSanitizeNames).to(file);
+                    .noCode(noCode).skipExceptions(skipExceptions).dontSanitizeNames(dontSanitizeNames)
+                    .computeFrames(computeFrames).to(file);
 
             if (!notHandleException) {
                 if (handler.hasException()) {

diff --git a/dex-translator/src/main/java/com/googlecode/d2j/dex/Dex2jar.java b/dex-translator/src/main/java/com/googlecode/d2j/dex/Dex2jar.java
@@ -20,9 +20,12 @@
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.spi.FileSystemProvider;
+import java.util.ArrayList;
 import java.util.HashMap;
+import java.util.List;
 import java.util.Map;
 import java.util.Random;
+import java.util.stream.Collectors;
 import org.objectweb.asm.ClassVisitor;
 import org.objectweb.asm.ClassWriter;
 import org.objectweb.asm.MethodVisitor;
@@ -57,6 +60,11 @@ public void doTranslate(final ByteArrayOutputStream baos) {
         doTranslate(null, baos);
     }
 
+    private static String toInternalClassName(String key) {
+        if (key.endsWith(";")) key = key.substring(1, key.length() - 1);
+        return key;
+    }
+
     /**
      * Translates a dex file to a class file and writes it to the specified destination path and stream.
      *
@@ -71,10 +79,42 @@ public void doTranslate(final Path dist, final ByteArrayOutputStream baos) {
         } catch (Exception ex) {
             exceptionHandler.handleFileException(ex);
         }
+
+        Map<String, String> parentsByName = fileNode.clzs.stream()
+                .filter(c -> c.superClass != null)
+                .collect(Collectors.toMap(
+                        c -> toInternalClassName(c.className),
+                        c -> toInternalClassName(c.superClass)));
+
         ClassVisitorFactory cvf = new ClassVisitorFactory() {
             @Override
             public ClassVisitor create(final String name) {
-                final ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_MAXS);
+                final ClassWriter cw = (readerConfig & DexFileReader.COMPUTE_FRAMES) == 0
+                        ? new ClassWriter(ClassWriter.COMPUTE_MAXS)
+                        : new ClassWriter(ClassWriter.COMPUTE_FRAMES) {
+                    @Override
+                    protected String getCommonSuperClass(String type1, String type2) {
+                        if (type1.equals(type2)) return type1;
+
+                        List<String> parentsOfType1 = new ArrayList<>();
+                        parentsOfType1.add(type1);
+                        while (parentsByName.containsKey(type1)) {
+                            type1 = parentsByName.get(type1);
+                            parentsOfType1.add(type1);
+                        }
+
+                        while (parentsByName.containsKey(type2)) {
+                            type2 = parentsByName.get(type2);
+                            if (parentsOfType1.contains(type2)) return type2;
+                        }
+
+                        try {
+                            return super.getCommonSuperClass(type1, type2);
+                        } catch (Throwable t) {
+                            return "java/util/Object";
+                        }
+                    }
+                };
                 final LambadaNameSafeClassAdapter rca = new LambadaNameSafeClassAdapter(cw,
                         (readerConfig & DexFileReader.DONT_SANITIZE_NAMES) != 0);
                 return new ClassVisitor(Constants.ASM_VERSION, rca) {
@@ -324,6 +364,15 @@ public Dex2jar dontSanitizeNames(boolean b) {
         return this;
     }
 
+    public Dex2jar computeFrames(boolean b) {
+        if (b) {
+            this.readerConfig |= DexFileReader.COMPUTE_FRAMES;
+        } else {
+            this.readerConfig &= ~DexFileReader.COMPUTE_FRAMES;
+        }
+        return this;
+    }
+
     public Dex2jar setRandom(Random random) {
         Dex2jar.random = random;
         return this;