1 /*
2 * Copyright (c) 2003, 2017, 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 "precompiled.hpp"
26 #include "classfile/symbolTable.hpp"
27 #include "classfile/systemDictionaryShared.hpp"
28 #include "classfile/verificationType.hpp"
29 #include "classfile/verifier.hpp"
30
31 VerificationType VerificationType::from_tag(u1 tag) {
32 switch (tag) {
33 case ITEM_Top: return bogus_type();
34 case ITEM_Integer: return integer_type();
35 case ITEM_Float: return float_type();
36 case ITEM_Double: return double_type();
37 case ITEM_Long: return long_type();
38 case ITEM_Null: return null_type();
39 default:
40 ShouldNotReachHere();
41 return bogus_type();
42 }
43 }
44
45 bool VerificationType::resolve_and_check_assignability(InstanceKlass* klass, Symbol* name,
46 Symbol* from_name, bool from_field_is_protected, bool from_is_array, bool from_is_object, TRAPS) {
47 HandleMark hm(THREAD);
48 Klass* this_class = SystemDictionary::resolve_or_fail(
49 name, Handle(THREAD, klass->class_loader()),
50 Handle(THREAD, klass->protection_domain()), true, CHECK_false);
51 if (log_is_enabled(Debug, class, resolve)) {
52 Verifier::trace_class_resolution(this_class, klass);
53 }
54
55 if (this_class->is_interface() && (!from_field_is_protected ||
56 from_name != vmSymbols::java_lang_Object())) {
57 // If we are not trying to access a protected field or method in
58 // java.lang.Object then, for arrays, we only allow assignability
59 // to interfaces java.lang.Cloneable and java.io.Serializable.
60 // Otherwise, we treat interfaces as java.lang.Object.
61 return !from_is_array ||
62 this_class == SystemDictionary::Cloneable_klass() ||
63 this_class == SystemDictionary::Serializable_klass();
64 } else if (from_is_object) {
65 Klass* from_class = SystemDictionary::resolve_or_fail(
66 from_name, Handle(THREAD, klass->class_loader()),
67 Handle(THREAD, klass->protection_domain()), true, CHECK_false);
68 if (log_is_enabled(Debug, class, resolve)) {
69 Verifier::trace_class_resolution(from_class, klass);
70 }
71 return InstanceKlass::cast(from_class)->is_subclass_of(this_class);
72 }
73
74 return false;
75 }
76
77 bool VerificationType::is_reference_assignable_from(
78 const VerificationType& from, ClassVerifier* context,
79 bool from_field_is_protected, TRAPS) const {
80 InstanceKlass* klass = context->current_class();
81 if (from.is_null()) {
82 // null is assignable to any reference
83 return true;
84 } else if (is_null()) {
85 return false;
86 } else if (name() == from.name()) {
87 return true;
88 } else if (is_object()) {
89 // We need check the class hierarchy to check assignability
90 if (name() == vmSymbols::java_lang_Object()) {
91 // any object or array is assignable to java.lang.Object
92 return true;
93 }
94
95 if (DumpSharedSpaces && SystemDictionaryShared::add_verification_constraint(klass,
96 name(), from.name(), from_field_is_protected, from.is_array(),
97 from.is_object())) {
98 // If add_verification_constraint() returns true, the resolution/check should be
99 // delayed until runtime.
100 return true;
101 }
102
103 return resolve_and_check_assignability(klass, name(), from.name(),
104 from_field_is_protected, from.is_array(), from.is_object(), THREAD);
105 } else if (is_array() && from.is_array()) {
106 VerificationType comp_this = get_component(context, CHECK_false);
107 VerificationType comp_from = from.get_component(context, CHECK_false);
108 if (!comp_this.is_bogus() && !comp_from.is_bogus()) {
109 return comp_this.is_component_assignable_from(comp_from, context,
110 from_field_is_protected, CHECK_false);
111 }
112 }
113 return false;
114 }
115
116 VerificationType VerificationType::get_component(ClassVerifier *context, TRAPS) const {
117 assert(is_array() && name()->utf8_length() >= 2, "Must be a valid array");
118 Symbol* component;
119 switch (name()->byte_at(1)) {
120 case 'Z': return VerificationType(Boolean);
121 case 'B': return VerificationType(Byte);
122 case 'C': return VerificationType(Char);
123 case 'S': return VerificationType(Short);
124 case 'I': return VerificationType(Integer);
125 case 'J': return VerificationType(Long);
126 case 'F': return VerificationType(Float);
127 case 'D': return VerificationType(Double);
128 case '[':
129 component = context->create_temporary_symbol(
130 name(), 1, name()->utf8_length(),
131 CHECK_(VerificationType::bogus_type()));
132 return VerificationType::reference_type(component);
133 case 'L':
134 component = context->create_temporary_symbol(
135 name(), 2, name()->utf8_length() - 1,
136 CHECK_(VerificationType::bogus_type()));
137 return VerificationType::reference_type(component);
138 default:
139 // Met an invalid type signature, e.g. [X
140 return VerificationType::bogus_type();
141 }
142 }
143
144 void VerificationType::print_on(outputStream* st) const {
145 switch (_u._data) {
146 case Bogus: st->print("top"); break;
147 case Category1: st->print("category1"); break;
148 case Category2: st->print("category2"); break;
149 case Category2_2nd: st->print("category2_2nd"); break;
150 case Boolean: st->print("boolean"); break;
151 case Byte: st->print("byte"); break;
152 case Short: st->print("short"); break;
153 case Char: st->print("char"); break;
154 case Integer: st->print("integer"); break;
155 case Float: st->print("float"); break;
156 case Long: st->print("long"); break;
157 case Double: st->print("double"); break;
158 case Long_2nd: st->print("long_2nd"); break;
159 case Double_2nd: st->print("double_2nd"); break;
160 case Null: st->print("null"); break;
161 case ReferenceQuery: st->print("reference type"); break;
162 case Category1Query: st->print("category1 type"); break;
163 case Category2Query: st->print("category2 type"); break;
164 case Category2_2ndQuery: st->print("category2_2nd type"); break;
165 default:
166 if (is_uninitialized_this()) {
167 st->print("uninitializedThis");
168 } else if (is_uninitialized()) {
169 st->print("uninitialized %d", bci());
170 } else {
171 name()->print_value_on(st);
172 }
173 }
174 }