1 files changed, 68 insertions, 0 deletions
diff --git a/src/main/java/com/code_intelligence/jazzer/android/DexFileManager.java b/src/main/java/com/code_intelligence/jazzer/android/DexFileManager.java
new file mode 100644
index 00000000..23d2eeec
--- /dev/null
+++ b/src/main/java/com/code_intelligence/jazzer/android/DexFileManager.java
@@ -0,0 +1,68 @@
+/*
+ * Copyright 2023 Code Intelligence GmbH
+ *
+ * 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.code_intelligence.jazzer.android;
+
+import java.io.ByteArrayOutputStream;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.lang.Math;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Enumeration;
+import java.util.jar.JarEntry;
+import java.util.jar.JarFile;
+
+public class DexFileManager {
+  private final static int MAX_READ_LENGTH = 2000000;
+
+  public static byte[] getBytecodeFromDex(String jarPath, String dexFile) throws IOException {
+    try (JarFile jarFile = new JarFile(jarPath)) {
+      JarEntry entry = jarFile.stream()
+                           .filter(jarEntry -> jarEntry.getName().equals(dexFile))
+                           .findFirst()
+                           .orElse(null);
+
+      if (entry == null) {
+        throw new IOException("Could not find dex file: " + dexFile);
+      }
+
+      try (InputStream is = jarFile.getInputStream(entry)) {
+        ByteArrayOutputStream out = new ByteArrayOutputStream();
+
+        byte[] buffer = new byte[64 * 104 * 1024];
+        int read;
+        while ((read = is.read(buffer)) != -1) {
+          out.write(buffer, 0, read);
+        }
+
+        return out.toByteArray();
+      }
+    }
+  }
+
+  public static String[] getDexFilesForJar(String jarpath) throws IOException {
+    try (JarFile jarFile = new JarFile(jarpath)) {
+      return jarFile.stream()
+          .map(JarEntry::getName)
+          .filter(entry -> entry.endsWith(".dex"))
+          .toArray(String[] ::new);
+    }
+  }
+}