Merge branch 'main' into develop

unimined · Jul 31, 2024 · 6b89a42 · 6b89a42
2 parents d58675d + 60b7456
commit 6b89a42
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diff --git a/README.md b/README.md
@@ -86,6 +86,9 @@ shadeDowngradedApi {
 The tasks have all the same flags as the extension, so you can change them separately, 
 their default value is to use the global one from the extension.
 
+If you are merging multiple downgraded jars, please merge from the downgradeJar tasks, and then shade on the resulting mono-jar.
+otherwise some API stubs may be missing, due to how shade only includes what is used.
+
 Optionally, you can also depend on the shadeDowngradedApi task when running build.
 
 ```gradle

diff --git a/docs/Bytecode Manipulation.md b/docs/Bytecode Manipulation.md
@@ -38,6 +38,7 @@ Stubs have several other fields that change their behavior:
     mostly for things like reflection and runtime class definition.
 * `noSpecial` indicates that the stub should not be used for `INVOKESPECIAL` calls.
 * `downgradeVersion` adds an extra argument to the stub for the original version of the class, this is useful for multi-version stubs, such as reflection.
+* `excludeChild` prevent a stub from being applied to a child-class of the target. for example, `String#isEmpty` is since java 6, but `CharSequence#isEmpty` is since java 15.
 
 ### Modify
 

diff --git a/java-api/src/java9/java/xyz/wagyourtail/jvmdg/j9/stub/java_base/J_L_ClassLoader.java b/java-api/src/java9/java/xyz/wagyourtail/jvmdg/j9/stub/java_base/J_L_ClassLoader.java
@@ -1,17 +1,60 @@
 package xyz.wagyourtail.jvmdg.j9.stub.java_base;
 
 
+import org.objectweb.asm.Opcodes;
+import org.objectweb.asm.Type;
+import org.objectweb.asm.tree.InsnList;
+import org.objectweb.asm.tree.InsnNode;
+import org.objectweb.asm.tree.MethodInsnNode;
+import org.objectweb.asm.tree.MethodNode;
+import xyz.wagyourtail.jvmdg.version.Modify;
 import xyz.wagyourtail.jvmdg.version.Ref;
 import xyz.wagyourtail.jvmdg.version.Stub;
 
+import java.util.Collections;
+import java.util.Map;
+import java.util.WeakHashMap;
+
 public class J_L_ClassLoader {
+    private static final Map<ClassLoader, String> nameMap = Collections.synchronizedMap(new WeakHashMap<>());
+
+    @Modify(ref = @Ref(value = "Ljava/lang/ClassLoader;", member = "<init>", desc = "(Ljava/lang/String;Ljava/lang/ClassLoader;)V"))
+    public static void init(MethodNode mnode, int i) {
+        MethodInsnNode node = (MethodInsnNode) mnode.instructions.get(i);
+        InsnList list = new InsnList();
+        // stack: ClassLoader (U), String, ClassLoader
+        list.add(new InsnNode(Opcodes.SWAP));
+        // stack: ClassLoader (U), ClassLoader, String
+        list.add(new InsnNode(Opcodes.DUP_X2));
+        // stack: String, ClassLoader (U), ClassLoader, String
+        list.add(new InsnNode(Opcodes.POP));
+        // stack: String, ClassLoader (U), ClassLoader
+        list.add(new InsnNode(Opcodes.DUP2));
+        // stack: String, ClassLoader (U), ClassLoader, ClassLoader (U), ClassLoader
+        // init
+        list.add(new MethodInsnNode(Opcodes.INVOKESPECIAL, "java/lang/ClassLoader", "<init>", "(Ljava/lang/ClassLoader;)V", false));
+        // stack: String, ClassLoader, ClassLoader
+        list.add(new InsnNode(Opcodes.POP));
+        // stack: String, ClassLoader
+        // call setName
+        list.add(new MethodInsnNode(Opcodes.INVOKESTATIC, Type.getInternalName(J_L_ClassLoader.class), "setClassloaderName", "(Ljava/lang/String;Ljava/lang/ClassLoader;)V", false));
+        // stack:
 
-    // TODO: stub init's...
+        mnode.instructions.insert(node, list);
+        mnode.instructions.remove(node);
+    }
+
+    public static void setClassloaderName(String name, ClassLoader classLoader) {
+        if (name != null && name.isEmpty()) {
+            throw new IllegalArgumentException("name must be non-empty or null");
+        }
+        nameMap.put(classLoader, name);
+    }
 
     @Stub
     public static String getName(ClassLoader classLoader) {
         // TODO: check if subclass actually overrides this method
-        return null;
+        return nameMap.get(classLoader);
     }
 
     @Stub

diff --git a/java-api/src/java9/java/xyz/wagyourtail/jvmdg/j9/stub/java_base/J_N_URLClassLoader.java b/java-api/src/java9/java/xyz/wagyourtail/jvmdg/j9/stub/java_base/J_N_URLClassLoader.java
@@ -0,0 +1,93 @@
+package xyz.wagyourtail.jvmdg.j9.stub.java_base;
+
+import org.objectweb.asm.Opcodes;
+import org.objectweb.asm.Type;
+import org.objectweb.asm.tree.InsnList;
+import org.objectweb.asm.tree.InsnNode;
+import org.objectweb.asm.tree.MethodInsnNode;
+import org.objectweb.asm.tree.MethodNode;
+import org.objectweb.asm.tree.VarInsnNode;
+import xyz.wagyourtail.jvmdg.version.Modify;
+import xyz.wagyourtail.jvmdg.version.Ref;
+
+public class J_N_URLClassLoader {
+
+    @Modify(ref = @Ref(value = "java/net/URLClassLoader", member = "<init>", desc = "(Ljava/lang/String;[Ljava/net/URL;Ljava/lang/ClassLoader;)V"))
+    public static void init1(MethodNode mnode, int i) {
+        MethodInsnNode node = (MethodInsnNode) mnode.instructions.get(i);
+        InsnList list = new InsnList();
+        // stack: URLClassLoader (U), String, URL[], ClassLoader
+        list.add(new InsnNode(Opcodes.DUP2_X1));
+        // stack: URLClassLoader (U), URL[], ClassLoader, String, URL[], ClassLoader
+        list.add(new InsnNode(Opcodes.POP2));
+        // stack: URLClassLoader (U), URL[], ClassLoader, String
+        list.add(new InsnNode(Opcodes.DUP2_X2));
+        // stack: ClassLoader, String, URLClassLoader (U), URL[], ClassLoader, String
+        list.add(new InsnNode(Opcodes.POP));
+        // stack: ClassLoader, String, URLClassLoader (U), URL[], ClassLoader
+        list.add(new InsnNode(Opcodes.DUP2_X1));
+        // stack: ClassLoader, String, URL[], ClassLoader, URLClassLoader (U), URL[], ClassLoader
+        list.add(new InsnNode(Opcodes.POP2));
+        // stack: ClassLoader, String, URL[], ClassLoader, URLClassLoader (U)
+        list.add(new InsnNode(Opcodes.DUP_X2));
+        // stack: ClassLoader, String, URLClassLoader (U), URL[], ClassLoader, URLClassLoader (U)
+        list.add(new InsnNode(Opcodes.DUP_X2));
+        // stack: ClassLoader, String, URLClassLoader (U), URLClassLoader (U), URL[], ClassLoader, URLClassLoader (U)
+        list.add(new InsnNode(Opcodes.POP));
+        // stack: ClassLoader, String, URLClassLoader (U), URLClassLoader (U), URL[], ClassLoader
+        // init
+        list.add(new MethodInsnNode(Opcodes.INVOKESPECIAL, "java/net/URLClassLoader", "<init>", "([Ljava/net/URL;Ljava/lang/ClassLoader;)V", false));
+        // stack: ClassLoader, String, URLClassLoader
+        // call setName
+        list.add(new MethodInsnNode(Opcodes.INVOKESTATIC, Type.getInternalName(J_L_ClassLoader.class), "setClassloaderName", "(Ljava/lang/String;Ljava/lang/ClassLoader;)V", false));
+        // stack: ClassLoader
+        list.add(new InsnNode(Opcodes.POP));
+        // stack:
+
+        mnode.instructions.insert(node, list);
+        mnode.instructions.remove(node);
+    }
+
+    @Modify(ref = @Ref(value = "java/net/URLClassLoader", member = "<init>", desc = "(Ljava/lang/String;[Ljava/net/URL;Ljava/lang/ClassLoader;Ljava/net/URLStreamHandlerFactory;)V"))
+    public static void init2(MethodNode mnode, int i) {
+        MethodInsnNode node = (MethodInsnNode) mnode.instructions.get(i);
+        InsnList list = new InsnList();
+        // stack: URLClassLoader (U), String, URL[], ClassLoader, URLStreamHandlerFactory
+
+        int var = mnode.maxLocals++;
+        list.add(new VarInsnNode(Opcodes.ASTORE, var));
+
+        // stack: URLClassLoader (U), String, URL[], ClassLoader
+        list.add(new InsnNode(Opcodes.DUP2_X1));
+        // stack: URLClassLoader (U), URL[], ClassLoader, String, URL[], ClassLoader
+        list.add(new InsnNode(Opcodes.POP2));
+        // stack: URLClassLoader (U), URL[], ClassLoader, String
+        list.add(new InsnNode(Opcodes.DUP2_X2));
+        // stack: ClassLoader, String, URLClassLoader (U), URL[], ClassLoader, String
+        list.add(new InsnNode(Opcodes.POP));
+        // stack: ClassLoader, String, URLClassLoader (U), URL[], ClassLoader
+        list.add(new InsnNode(Opcodes.DUP2_X1));
+        // stack: ClassLoader, String, URL[], ClassLoader, URLClassLoader (U), URL[], ClassLoader
+        list.add(new InsnNode(Opcodes.POP2));
+        // stack: ClassLoader, String, URL[], ClassLoader, URLClassLoader (U)
+        list.add(new InsnNode(Opcodes.DUP_X2));
+        // stack: ClassLoader, String, URLClassLoader (U), URL[], ClassLoader, URLClassLoader (U)
+        list.add(new InsnNode(Opcodes.DUP_X2));
+        // stack: ClassLoader, String, URLClassLoader (U), URLClassLoader (U), URL[], ClassLoader, URLClassLoader (U)
+        list.add(new InsnNode(Opcodes.POP));
+        // stack: ClassLoader, String, URLClassLoader (U), URLClassLoader (U), URL[], ClassLoader
+        list.add(new VarInsnNode(Opcodes.ALOAD, var));
+        // stack: ClassLoader, String, URLClassLoader (U), URLClassLoader (U), URL[], ClassLoader, URLStreamHandlerFactory
+        // init
+        list.add(new MethodInsnNode(Opcodes.INVOKESPECIAL, "java/net/URLClassLoader", "<init>", "([Ljava/net/URL;Ljava/lang/ClassLoader;Ljava/net/URLStreamHandlerFactory;)V", false));
+        // stack: ClassLoader, String, URLClassLoader
+        // call setName
+        list.add(new MethodInsnNode(Opcodes.INVOKESTATIC, Type.getInternalName(J_L_ClassLoader.class), "setClassloaderName", "(Ljava/lang/String;Ljava/lang/ClassLoader;)V", false));
+        // stack: ClassLoader
+        list.add(new InsnNode(Opcodes.POP));
+        // stack:
+
+        mnode.instructions.insert(node, list);
+        mnode.instructions.remove(node);
+    }
+}
diff --git a/java-api/src/main/java/xyz/wagyourtail/jvmdg/providers/Java9Downgrader.java b/java-api/src/main/java/xyz/wagyourtail/jvmdg/providers/Java9Downgrader.java
@@ -106,6 +106,7 @@ public void init() {
         // URLStreamHandlerProvider
         stub(J_N_Buffer.class);
         stub(J_N_F_Path.class);
+        stub(J_N_URLClassLoader.class);
         // AuthProvider
         // DrbgParameters
         // KeyStore

diff --git a/testing/downgrade/src/main/java/xyz/wagyourtail/downgradetest/TestClassloader.java b/testing/downgrade/src/main/java/xyz/wagyourtail/downgradetest/TestClassloader.java
@@ -0,0 +1,27 @@
+package xyz.wagyourtail.downgradetest;
+
+import java.net.URLClassLoader;
+
+public class TestClassloader {
+
+    public static void main(String[] args) {
+        URLClassLoader cl = new URLClassLoader("name1", new java.net.URL[0], TestClassloader.class.getClassLoader());
+        System.out.println(cl.getName());
+
+        URLClassLoader cl2 = new URLClassLoader("name2", new java.net.URL[0], TestClassloader.class.getClassLoader(), null);
+        System.out.println(cl2.getName());
+
+        CLExt cl3 = new CLExt(TestClassloader.class.getClassLoader());
+        System.out.println(cl3.getName());
+
+    }
+
+    private static class CLExt extends ClassLoader {
+
+        public CLExt(ClassLoader parent) {
+            super("name3", parent);
+        }
+
+    }
+
+}