1 /*
2 * Copyright (c) 2003, 2025, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "cds/cdsConfig.hpp"
26 #include "classfile/symbolTable.hpp"
27 #include "classfile/systemDictionary.hpp"
28 #include "classfile/systemDictionaryShared.hpp"
29 #include "classfile/verificationType.hpp"
30 #include "classfile/verifier.hpp"
31 #include "classfile/vmClasses.hpp"
32 #include "classfile/vmSymbols.hpp"
33 #include "logging/log.hpp"
34 #include "oops/klass.inline.hpp"
35 #include "runtime/handles.inline.hpp"
36
37 VerificationType VerificationType::from_tag(u1 tag) {
38 switch (tag) {
39 case ITEM_Top: return bogus_type();
40 case ITEM_Integer: return integer_type();
41 case ITEM_Float: return float_type();
42 case ITEM_Double: return double_type();
43 case ITEM_Long: return long_type();
44 case ITEM_Null: return null_type();
45 default:
46 ShouldNotReachHere();
47 return bogus_type();
48 }
49 }
50
51 bool VerificationType::resolve_and_check_assignability(InstanceKlass* klass, Symbol* name,
52 Symbol* from_name, bool from_field_is_protected, bool from_is_array, bool from_is_object, TRAPS) {
53 HandleMark hm(THREAD);
54 Klass* this_class;
55 if (klass->is_hidden() && klass->name() == name) {
56 this_class = klass;
57 } else {
58 this_class = SystemDictionary::resolve_or_fail(
59 name, Handle(THREAD, klass->class_loader()), true, CHECK_false);
60 if (log_is_enabled(Debug, class, resolve)) {
61 Verifier::trace_class_resolution(this_class, klass);
62 }
63 }
64
65 if (this_class->is_interface() && (!from_field_is_protected ||
66 from_name != vmSymbols::java_lang_Object())) {
67 // If we are not trying to access a protected field or method in
68 // java.lang.Object then, for arrays, we only allow assignability
69 // to interfaces java.lang.Cloneable and java.io.Serializable.
70 // Otherwise, we treat interfaces as java.lang.Object.
71 return !from_is_array ||
72 this_class == vmClasses::Cloneable_klass() ||
73 this_class == vmClasses::Serializable_klass();
74 } else if (from_is_object) {
75 Klass* from_class;
76 if (klass->is_hidden() && klass->name() == from_name) {
77 from_class = klass;
78 } else {
79 from_class = SystemDictionary::resolve_or_fail(
80 from_name, Handle(THREAD, klass->class_loader()), true, CHECK_false);
81 if (log_is_enabled(Debug, class, resolve)) {
82 Verifier::trace_class_resolution(from_class, klass);
83 }
84 }
85 return from_class->is_subclass_of(this_class);
86 }
87
88 return false;
89 }
90
91 bool VerificationType::is_reference_assignable_from(
92 const VerificationType& from, ClassVerifier* context,
93 bool from_field_is_protected, TRAPS) const {
94 InstanceKlass* klass = context->current_class();
95 if (from.is_null()) {
96 // null is assignable to any reference
97 return true;
98 } else if (is_null()) {
99 return false;
100 } else if (name() == from.name()) {
101 return true;
102 } else if (is_object()) {
103 // We need check the class hierarchy to check assignability
104 if (name() == vmSymbols::java_lang_Object()) {
105 // any object or array is assignable to java.lang.Object
106 return true;
107 }
108
109 if (CDSConfig::is_dumping_archive()) {
110 if (SystemDictionaryShared::add_verification_constraint(klass,
111 name(), from.name(), from_field_is_protected, from.is_array(),
112 from.is_object())) {
113 // If add_verification_constraint() returns true, the resolution/check should be
114 // delayed until runtime.
115 return true;
116 }
117 }
118
119 return resolve_and_check_assignability(klass, name(), from.name(),
120 from_field_is_protected, from.is_array(), from.is_object(), THREAD);
121 } else if (is_array() && from.is_array()) {
122 VerificationType comp_this = get_component(context);
123 VerificationType comp_from = from.get_component(context);
124 if (!comp_this.is_bogus() && !comp_from.is_bogus()) {
125 return comp_this.is_component_assignable_from(comp_from, context,
126 from_field_is_protected, THREAD);
127 }
128 }
129 return false;
130 }
131
132 VerificationType VerificationType::get_component(ClassVerifier *context) const {
133 assert(is_array() && name()->utf8_length() >= 2, "Must be a valid array");
134 SignatureStream ss(name(), false);
135 ss.skip_array_prefix(1);
136 switch (ss.type()) {
137 case T_BOOLEAN: return VerificationType(Boolean);
138 case T_BYTE: return VerificationType(Byte);
139 case T_CHAR: return VerificationType(Char);
140 case T_SHORT: return VerificationType(Short);
141 case T_INT: return VerificationType(Integer);
142 case T_LONG: return VerificationType(Long);
143 case T_FLOAT: return VerificationType(Float);
144 case T_DOUBLE: return VerificationType(Double);
145 case T_ARRAY:
146 case T_OBJECT: {
147 guarantee(ss.is_reference(), "unchecked verifier input?");
148 Symbol* component = ss.as_symbol();
149 // Create another symbol to save as signature stream unreferences this symbol.
150 Symbol* component_copy = context->create_temporary_symbol(component);
151 assert(component_copy == component, "symbols don't match");
152 return VerificationType::reference_type(component_copy);
153 }
154 default:
155 // Met an invalid type signature, e.g. [X
156 return VerificationType::bogus_type();
157 }
158 }
159
160 void VerificationType::print_on(outputStream* st) const {
161 switch (_u._data) {
162 case Bogus: st->print("top"); break;
163 case Category1: st->print("category1"); break;
164 case Category2: st->print("category2"); break;
165 case Category2_2nd: st->print("category2_2nd"); break;
166 case Boolean: st->print("boolean"); break;
167 case Byte: st->print("byte"); break;
168 case Short: st->print("short"); break;
169 case Char: st->print("char"); break;
170 case Integer: st->print("integer"); break;
171 case Float: st->print("float"); break;
172 case Long: st->print("long"); break;
173 case Double: st->print("double"); break;
174 case Long_2nd: st->print("long_2nd"); break;
175 case Double_2nd: st->print("double_2nd"); break;
176 case Null: st->print("null"); break;
177 case ReferenceQuery: st->print("reference type"); break;
178 case Category1Query: st->print("category1 type"); break;
179 case Category2Query: st->print("category2 type"); break;
180 case Category2_2ndQuery: st->print("category2_2nd type"); break;
181 default:
182 if (is_uninitialized_this()) {
183 st->print("uninitializedThis");
184 } else if (is_uninitialized()) {
185 st->print("uninitialized %d", bci());
186 } else {
187 if (name() != nullptr) {
188 name()->print_value_on(st);
189 } else {
190 st->print_cr("null");
191 }
192 }
193 }
194 }