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An unofficial backport of the JDK Classfile API to Java 17
/*
* Copyright (c) 2022, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package io.github.dmlloyd.classfile.impl.verifier;
import java.util.Arrays;
/**
* @see hotspot/share/classfile/stackMapFrame.hpp
* @see hotspot/share/classfile/stackMapFrame.cpp
*/
class VerificationFrame {
public static final int FLAG_THIS_UNINIT = 0x01;
private int _offset;
private int _locals_size, _stack_size;
private int _stack_mark;
private final int _max_locals, _max_stack;
private int _flags;
private final VerificationType[] _locals, _stack;
private final VerifierImpl _verifier;
public VerificationFrame(int offset, int flags, int locals_size, int stack_size, int max_locals, int max_stack, VerificationType[] locals, VerificationType[] stack, VerifierImpl v) {
this._offset = offset;
this._locals_size = locals_size;
this._stack_size = stack_size;
this._stack_mark = -1;
this._max_locals = max_locals;
this._max_stack = max_stack;
this._flags = flags;
this._locals = locals;
this._stack = stack;
this._verifier = v;
}
@Override
public String toString() {
return "frame @" + _offset + " with locals " + (_locals == null ? "[]" : Arrays.asList(_locals)) + " and stack " + (_stack == null ? "[]" : Arrays.asList(_stack));
}
void set_offset(int offset) {
this._offset = offset;
}
void set_flags(int flags) {
_flags = flags;
}
void set_locals_size(int locals_size) {
_locals_size = locals_size;
}
void set_stack_size(int stack_size) {
_stack_size = _stack_mark = stack_size;
}
int offset() {
return _offset;
}
VerifierImpl verifier() {
return _verifier;
}
int flags() {
return _flags;
}
int locals_size() {
return _locals_size;
}
VerificationType[] locals() {
return _locals;
}
int stack_size() {
return _stack_size;
}
VerificationType[] stack() {
return _stack;
}
int max_locals() {
return _max_locals;
}
boolean flag_this_uninit() {
return (_flags & FLAG_THIS_UNINIT) == FLAG_THIS_UNINIT;
}
void reset() {
for (int i = 0; i < _max_locals; i++) {
_locals[i] = VerificationType.bogus_type;
}
for (int i = 0; i < _max_stack; i++) {
_stack[i] = VerificationType.bogus_type;
}
}
void set_mark() {
if (_stack_mark != -1) {
for (int i = _stack_mark - 1; i >= _stack_size; --i) {
_stack[i] = VerificationType.bogus_type;
}
_stack_mark = _stack_size;
}
}
void push_stack(VerificationType type) {
if (type.is_check()) _verifier.verifyError("Must be a real type");
if (_stack_size >= _max_stack) {
_verifier.verifyError("Operand stack overflow");
}
_stack[_stack_size++] = type;
}
void push_stack_2(VerificationType type1, VerificationType type2) {
if (!(type1.is_long() || type1.is_double())) _verifier.verifyError("must be long/double");
if (!(type2.is_long2() || type2.is_double2())) _verifier.verifyError("must be long/double_2");
if (_stack_size >= _max_stack - 1) {
_verifier.verifyError("Operand stack overflow");
}
_stack[_stack_size++] = type1;
_stack[_stack_size++] = type2;
}
VerificationType pop_stack() {
if (_stack_size <= 0) {
_verifier.verifyError("Operand stack underflow");
}
return _stack[--_stack_size];
}
VerificationType pop_stack(VerificationType type) {
if (_stack_size != 0) {
VerificationType top = _stack[_stack_size - 1];
boolean subtype = type.is_assignable_from(top, verifier());
if (subtype) {
--_stack_size;
return top;
}
}
return pop_stack_ex(type);
}
void pop_stack_2(VerificationType type1, VerificationType type2) {
if (!(type1.is_long2() || type1.is_double2())) _verifier.verifyError("must be long/double");
if (!(type2.is_long() || type2.is_double())) _verifier.verifyError("must be long/double_2");
if (_stack_size >= 2) {
VerificationType top1 = _stack[_stack_size - 1];
boolean subtype1 = type1.is_assignable_from(top1, verifier());
VerificationType top2 = _stack[_stack_size - 2];
boolean subtype2 = type2.is_assignable_from(top2, verifier());
if (subtype1 && subtype2) {
_stack_size -= 2;
return;
}
}
pop_stack_ex(type1);
pop_stack_ex(type2);
}
VerificationFrame(int max_locals, int max_stack, VerifierImpl verifier) {
_offset = 0;
_locals_size = 0;
_stack_size = 0;
_stack_mark = 0;
_max_locals = max_locals;
_max_stack = max_stack;
_flags = 0;
_verifier = verifier;
_locals = new VerificationType[max_locals];
_stack = new VerificationType[max_stack];
for (int i = 0; i < max_locals; i++) {
_locals[i] = VerificationType.bogus_type;
}
for (int i = 0; i < max_stack; i++) {
_stack[i] = VerificationType.bogus_type;
}
}
VerificationFrame frame_in_exception_handler(int flags) {
return new VerificationFrame(_offset, flags, _locals_size, 0,
_max_locals, _max_stack, _locals, new VerificationType[1],
_verifier);
}
void initialize_object(VerificationType old_object, VerificationType new_object) {
int i;
for (i = 0; i < _max_locals; i++) {
if (_locals[i].equals(old_object)) {
_locals[i] = new_object;
}
}
for (i = 0; i < _stack_size; i++) {
if (_stack[i].equals(old_object)) {
_stack[i] = new_object;
}
}
if (old_object.is_uninitialized_this(_verifier)) {
_flags = 0;
}
}
VerificationType set_locals_from_arg(VerificationWrapper.MethodWrapper m, VerificationType thisKlass) {
var ss = new VerificationSignature(m.descriptor(), true, _verifier);
int init_local_num = 0;
if (!m.isStatic()) {
init_local_num++;
if (VerifierImpl.object_initializer_name.equals(m.name()) && !VerifierImpl.java_lang_Object.equals(thisKlass.name())) {
_locals[0] = VerificationType.uninitialized_this_type;
_flags |= FLAG_THIS_UNINIT;
} else {
_locals[0] = thisKlass;
}
}
while (!ss.atReturnType()) {
init_local_num += _verifier.change_sig_to_verificationType(ss, _locals, init_local_num);
ss.next();
}
_locals_size = init_local_num;
switch (ss.type()) {
case T_OBJECT:
case T_ARRAY:
{
String sig = ss.asSymbol();
return VerificationType.reference_type(sig);
}
case T_INT: return VerificationType.integer_type;
case T_BYTE: return VerificationType.byte_type;
case T_CHAR: return VerificationType.char_type;
case T_SHORT: return VerificationType.short_type;
case T_BOOLEAN: return VerificationType.boolean_type;
case T_FLOAT: return VerificationType.float_type;
case T_DOUBLE: return VerificationType.double_type;
case T_LONG: return VerificationType.long_type;
case T_VOID: return VerificationType.bogus_type;
default:
_verifier.verifyError("Should not reach here");
return VerificationType.bogus_type;
}
}
void copy_locals(VerificationFrame src) {
int len = src.locals_size() < _locals_size ? src.locals_size() : _locals_size;
if (len > 0) System.arraycopy(src.locals(), 0, _locals, 0, len);
}
void copy_stack(VerificationFrame src) {
int len = src.stack_size() < _stack_size ? src.stack_size() : _stack_size;
if (len > 0) System.arraycopy(src.stack(), 0, _stack, 0, len);
}
private int is_assignable_to(VerificationType[] from, VerificationType[] to, int len) {
int i = 0;
for (; i < len; i++) {
if (!to[i].is_assignable_from(from[i], verifier())) {
break;
}
}
return i;
}
boolean is_assignable_to(VerificationFrame target) {
if (_max_locals != target.max_locals()) {
_verifier.verifyError("Locals size mismatch", this, target);
}
if (_stack_size != target.stack_size()) {
_verifier.verifyError("Stack size mismatch", this, target);
}
int mismatch_loc;
mismatch_loc = is_assignable_to(_locals, target.locals(), target.locals_size());
if (mismatch_loc != target.locals_size()) {
_verifier.verifyError("Bad type", this, target);
}
mismatch_loc = is_assignable_to(_stack, target.stack(), _stack_size);
if (mismatch_loc != _stack_size) {
_verifier.verifyError("Bad type", this, target);
}
if ((_flags | target.flags()) == target.flags()) {
return true;
} else {
_verifier.verifyError("Bad flags", this, target);
}
return false;
}
VerificationType pop_stack_ex(VerificationType type) {
if (_stack_size <= 0) {
_verifier.verifyError("Operand stack underflow");
}
VerificationType top = _stack[--_stack_size];
boolean subtype = type.is_assignable_from(top, verifier());
if (!subtype) {
_verifier.verifyError("Bad type on operand stack");
}
return top;
}
VerificationType get_local(int index, VerificationType type) {
if (index >= _max_locals) {
_verifier.verifyError("Local variable table overflow");
}
boolean subtype = type.is_assignable_from(_locals[index],
verifier());
if (!subtype) {
_verifier.verifyError("Bad local variable type");
}
if(index >= _locals_size) { _locals_size = index + 1; }
return _locals[index];
}
void get_local_2(int index, VerificationType type1, VerificationType type2) {
if (!(type1.is_long() || type1.is_double())) _verifier.verifyError("must be long/double");
if (!(type2.is_long2() || type2.is_double2())) _verifier.verifyError("must be long/double_2");
if (index >= _locals_size - 1) {
_verifier.verifyError("get long/double overflows locals");
}
boolean subtype = type1.is_assignable_from(_locals[index], verifier());
if (!subtype) {
_verifier.verifyError("Bad local variable type");
} else {
subtype = type2.is_assignable_from(_locals[index + 1], verifier());
if (!subtype) {
_verifier.verifyError("Bad local variable type");
}
}
}
void set_local(int index, VerificationType type) {
if (type.is_check()) _verifier.verifyError("Must be a real type");
if (index >= _max_locals) {
_verifier.verifyError("Local variable table overflow");
}
if (_locals[index].is_double() || _locals[index].is_long()) {
if ((index + 1) >= _locals_size) _verifier.verifyError("Local variable table overflow");
_locals[index + 1] = VerificationType.bogus_type;
}
if (_locals[index].is_double2() || _locals[index].is_long2()) {
if (index < 1) _verifier.verifyError("Local variable table underflow");
_locals[index - 1] = VerificationType.bogus_type;
}
_locals[index] = type;
if (index >= _locals_size) {
for (int i=_locals_size; i= _max_locals - 1) {
_verifier.verifyError("Local variable table overflow");
}
if (_locals[index+1].is_double() || _locals[index+1].is_long()) {
if ((index + 2) >= _locals_size) _verifier.verifyError("Local variable table overflow");
_locals[index + 2] = VerificationType.bogus_type;
}
if (_locals[index].is_double2() || _locals[index].is_long2()) {
if (index < 1) _verifier.verifyError("Local variable table underflow");
_locals[index - 1] = VerificationType.bogus_type;
}
_locals[index] = type1;
_locals[index+1] = type2;
if (index >= _locals_size - 1) {
for (int i=_locals_size; i © 2015 - 2024 Weber Informatics LLC | Privacy Policy