pageSize fix for some JDK versions and implement getCallerClass(depth)

xxDark · May 19, 2022 · e2f6c5c · e2f6c5c
1 parent 61ee405
commit e2f6c5c
Show file tree

Hide file tree

Showing 3 changed files with 61 additions and 26 deletions.
diff --git a/src/main/java/dev/xdark/ssvm/natives/ReflectionNatives.java b/src/main/java/dev/xdark/ssvm/natives/ReflectionNatives.java
@@ -1,6 +1,7 @@
 package dev.xdark.ssvm.natives;
 
 import dev.xdark.ssvm.VirtualMachine;
+import dev.xdark.ssvm.api.MethodInvoker;
 import dev.xdark.ssvm.api.VMInterface;
 import dev.xdark.ssvm.asm.Modifier;
 import dev.xdark.ssvm.execution.ExecutionContext;
@@ -35,31 +36,40 @@ public void init(VirtualMachine vm) {
 				throw new IllegalStateException("Unable to locate Reflection class");
 			}
 		}
-		vmi.setInvoker(reflection, "getCallerClass", "()Ljava/lang/Class;", ctx -> {
+		vmi.setInvoker(reflection, "getCallerClass", "()Ljava/lang/Class;", getCallerClass(false));
+		vmi.setInvoker(reflection, "getCallerClass", "(I)Ljava/lang/Class;", getCallerClass(true));
+		vmi.setInvoker(reflection, "getClassAccessFlags", "(Ljava/lang/Class;)I", ctx -> {
+			JavaClass klass = ctx.getLocals().<JavaValue<JavaClass>>load(0).getValue();
+			ctx.setResult(IntValue.of(Modifier.eraseClass(klass.getModifiers())));
+			return Result.ABORT;
+		});
+	}
+
+	private static MethodInvoker getCallerClass(boolean useDepth) {
+		return ctx -> {
+			VirtualMachine vm = ctx.getVM();
 			Backtrace backtrace = vm.currentThread().getBacktrace();
 			int count = backtrace.count();
-			JavaMethod caller = backtrace.get(count - 2).getExecutionContext().getMethod();
-			int offset = 3;
+			int callerOffset = useDepth ? ctx.getLocals().load(0).asInt() + 1 : 2;
+			JavaMethod caller = backtrace.get(count - callerOffset).getExecutionContext().getMethod();
+			if (!useDepth) {
+				callerOffset++;
+			}
 			if (caller.isCallerSensitive()) {
 				while (true) {
-					StackFrame frame = backtrace.get(count - offset);
+					StackFrame frame = backtrace.get(count - callerOffset);
 					ExecutionContext frameCtx = frame.getExecutionContext();
 					if (frameCtx == null) break;
 					JavaMethod method = frameCtx.getMethod();
 					if (Modifier.isCallerSensitive(method.getAccess())) {
-						offset++;
+						callerOffset++;
 					} else {
 						break;
 					}
 				}
 			}
-			ctx.setResult(backtrace.get(count - offset).getDeclaringClass().getOop());
+			ctx.setResult(backtrace.get(count - callerOffset).getDeclaringClass().getOop());
 			return Result.ABORT;
-		});
-		vmi.setInvoker(reflection, "getClassAccessFlags", "(Ljava/lang/Class;)I", ctx -> {
-			JavaClass klass = ctx.getLocals().<JavaValue<JavaClass>>load(0).getValue();
-			ctx.setResult(IntValue.of(Modifier.eraseClass(klass.getModifiers())));
-			return Result.ABORT;
-		});
+		};
 	}
 }
diff --git a/src/main/java/dev/xdark/ssvm/natives/UnsafeNatives.java b/src/main/java/dev/xdark/ssvm/natives/UnsafeNatives.java
@@ -366,10 +366,15 @@ private static void init(VirtualMachine vm, InstanceJavaClass unsafe, UnsafeHelp
 			ctx.setResult(value instanceof InstanceJavaClass && ((InstanceJavaClass) value).shouldBeInitialized() ? IntValue.ONE : IntValue.ZERO);
 			return Result.ABORT;
 		});
-		vmi.setInvoker(unsafe, uhelper.pageSize(), "()I", ctx -> {
+		MethodInvoker pageSize = ctx -> {
 			ctx.setResult(IntValue.of(vm.getMemoryManager().pageSize()));
 			return Result.ABORT;
-		});
+		};
+		for (String str : new String[] {"pageSize0", "pageSize"}) {
+			if (vmi.setInvoker(unsafe, str, "()I", pageSize)) {
+				break;
+			}
+		}
 		vmi.setInvoker(unsafe, "getLongVolatile", "(Ljava/lang/Object;J)J", ctx -> {
 			Locals locals = ctx.getLocals();
 			MemoryManager memoryManager = vm.getMemoryManager();
@@ -621,8 +626,6 @@ private interface UnsafeHelper {
 
 		String shouldBeInitialized();
 
-		String pageSize();
-
 		String compareAndSetObject();
 
 		String copyMemory();
@@ -705,11 +708,6 @@ public String shouldBeInitialized() {
 			return "shouldBeInitialized";
 		}
 
-		@Override
-		public String pageSize() {
-			return "pageSize";
-		}
-
 		@Override
 		public String compareAndSetObject() {
 			return null; // No method for JDK 8
@@ -798,11 +796,6 @@ public String shouldBeInitialized() {
 			return "shouldBeInitialized0";
 		}
 
-		@Override
-		public String pageSize() {
-			return "pageSize0";
-		}
-
 		@Override
 		public String compareAndSetObject() {
 			return "compareAndSetObject";

diff --git a/src/test/java/dev/xdark/ssvm/enhanced/CallerTest.java b/src/test/java/dev/xdark/ssvm/enhanced/CallerTest.java
@@ -0,0 +1,32 @@
+package dev.xdark.ssvm.enhanced;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.condition.EnabledOnJre;
+import org.junit.jupiter.api.condition.JRE;
+import sun.reflect.Reflection;
+
+@EnabledOnJre(JRE.JAVA_8)
+public class CallerTest {
+
+	@Test
+	public void doTest() {
+		TestUtil.test(CallerTest.class, true);
+	}
+
+	@VMTest
+	private static void callerTest() {
+		if (Reflection.getCallerClass(0) != Reflection.class) {
+			throw new IllegalStateException();
+		}
+		if (Reflection.getCallerClass(1) != CallerTest.class) {
+			throw new IllegalStateException();
+		}
+		callerTestInner();
+	}
+
+	private static void callerTestInner() {
+		if (Reflection.getCallerClass() != CallerTest.class) {
+			throw new IllegalStateException();
+		}
+	}
+}