public static ArtMethod hook(Constructor<?> originalMethod, Method replacementMethod) {
Assertions.argumentNotNull(originalMethod, "originalMethod");
Assertions.argumentNotNull(replacementMethod, "replacementMethod");
if (replacementMethod.getReturnType() != Void.TYPE)
throw new IllegalArgumentException("return types of replacementMethod has to be 'void'");
return hook(ArtMethod.of(originalMethod), ArtMethod.of(replacementMethod));
}
public static OriginalMethod hook(
Method originalMethod, Method replacementMethod, String backupIdentifier) {
ArtMethod backArt = hook(originalMethod, replacementMethod);
Method backupMethod = (Method) backArt.getAssociatedMethod();
backupMethod.setAccessible(true);
OriginalMethod.store(originalMethod, backupMethod, backupIdentifier);
return new OriginalMethod(backupMethod);
}
private static ArtMethod hook(ArtMethod original, ArtMethod replacement) {
HookPage page = handleHookPage(original, replacement);
ArtMethod backArt = original.clone();
backArt.makePrivate();
if (getQuickCompiledCodeSize(original) < INSTRUCTION_SET_HELPER.sizeOfDirectJump()) {
original.setEntryPointFromQuickCompiledCode(page.getCallHook());
} else {
page.activate();
}
return backArt;
}
public static ArtMethod hook(Method originalMethod, Method replacementMethod) {
Assertions.argumentNotNull(originalMethod, "originalMethod");
Assertions.argumentNotNull(replacementMethod, "replacementMethod");
if (originalMethod == replacementMethod || originalMethod.equals(replacementMethod))
throw new IllegalArgumentException("originalMethod and replacementMethod can't be the same");
if (!replacementMethod.getReturnType().isAssignableFrom(originalMethod.getReturnType()))
throw new IllegalArgumentException(
"return types of originalMethod and replacementMethod do not match");
return hook(ArtMethod.of(originalMethod), ArtMethod.of(replacementMethod));
}
private static HookPage handleHookPage(ArtMethod original, ArtMethod replacement) {
long originalEntryPoint =
INSTRUCTION_SET_HELPER.toMem(original.getEntryPointFromQuickCompiledCode());
if (!pages.containsKey(originalEntryPoint)) {
pages.put(
originalEntryPoint,
new HookPage(
INSTRUCTION_SET_HELPER, originalEntryPoint, getQuickCompiledCodeSize(original)));
}
HookPage page = pages.get(originalEntryPoint);
page.addHook(new HookPage.Hook(original, replacement));
page.update();
return page;
}
static {
try {
boolean isArm = true; // TODO: logic
if (isArm) {
if ((ArtMethod.of(ArtMethod.class.getDeclaredMethod("of", Method.class))
.getEntryPointFromQuickCompiledCode()
& 1)
== 1) {
INSTRUCTION_SET_HELPER = new Thumb2();
} else {
INSTRUCTION_SET_HELPER = new Arm32();
}
}
logd("Using: " + INSTRUCTION_SET_HELPER.getName());
} catch (Exception ignored) {
}
}
private static int getQuickCompiledCodeSize(ArtMethod method) {
long entryPoint = INSTRUCTION_SET_HELPER.toMem(method.getEntryPointFromQuickCompiledCode());
long sizeInfo1 = entryPoint - 4;
byte[] bytes = Memory.get(sizeInfo1, 4);
return ByteBuffer.wrap(bytes).order(ByteOrder.LITTLE_ENDIAN).getInt();
}
