1 /*
2 * Copyright (c) 1998, 2006, 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 // The verifier class
26 class Verifier : AllStatic {
27 public:
28 enum {
29 STACKMAP_ATTRIBUTE_MAJOR_VERSION = 50,
30 INVOKEDYNAMIC_MAJOR_VERSION = 51
31 };
32 typedef enum { ThrowException, NoException } Mode;
33
34 /**
35 * Verify the bytecodes for a class. If 'throw_exception' is true
36 * then the appropriate VerifyError or ClassFormatError will be thrown.
37 * Otherwise, no exception is thrown and the return indicates the
38 * error.
39 */
40 static bool verify(instanceKlassHandle klass, Mode mode, bool should_verify_class, TRAPS);
41
42 // Return false if the class is loaded by the bootstrap loader,
43 // or if defineClass was called requesting skipping verification
44 // -Xverify:all/none override this value
45 static bool should_verify_for(oop class_loader, bool should_verify_class);
46
47 // Relax certain verifier checks to enable some broken 1.1 apps to run on 1.2.
48 static bool relax_verify_for(oop class_loader);
49
50 private:
51 static bool is_eligible_for_verification(instanceKlassHandle klass, bool should_verify_class);
52 static symbolHandle inference_verify(
53 instanceKlassHandle klass, char* msg, size_t msg_len, TRAPS);
54 };
55
56 class RawBytecodeStream;
57 class StackMapFrame;
58 class StackMapTable;
59
60 // Summary of verifier's memory usage:
61 // StackMapTable is stack allocated.
62 // StackMapFrame are resource allocated. There is one ResourceMark
63 // for each method.
64 // There is one mutable StackMapFrame (current_frame) which is updated
65 // by abstract bytecode interpretation. frame_in_exception_handler() returns
66 // a frame that has a mutable one-item stack (ready for pushing the
67 // catch type exception object). All the other StackMapFrame's
68 // are immutable (including their locals and stack arrays) after
69 // their constructions.
70 // locals/stack arrays in StackMapFrame are resource allocated.
71 // locals/stack arrays can be shared between StackMapFrame's, except
72 // the mutable StackMapFrame (current_frame).
73 // Care needs to be taken to make sure resource objects don't outlive
74 // the lifetime of their ResourceMark.
75
76 // These macros are used similarly to CHECK macros but also check
77 // the status of the verifier and return if that has an error.
78 #define CHECK_VERIFY(verifier) \
79 CHECK); if ((verifier)->has_error()) return; (0
80 #define CHECK_VERIFY_(verifier, result) \
81 CHECK_(result)); if ((verifier)->has_error()) return (result); (0
82
83 // A new instance of this class is created for each class being verified
84 class ClassVerifier : public StackObj {
85 private:
86 Thread* _thread;
87 symbolHandle _exception_type;
88 char* _message;
89 size_t _message_buffer_len;
90
91 void verify_method(methodHandle method, TRAPS);
92 char* generate_code_data(methodHandle m, u4 code_length, TRAPS);
93 void verify_exception_handler_table(u4 code_length, char* code_data, int& min, int& max, TRAPS);
94 void verify_local_variable_table(u4 code_length, char* code_data, TRAPS);
95
96 VerificationType cp_ref_index_to_type(
97 int index, constantPoolHandle cp, TRAPS) {
98 return cp_index_to_type(cp->klass_ref_index_at(index), cp, THREAD);
99 }
100
101 bool is_protected_access(
102 instanceKlassHandle this_class, klassOop target_class,
103 symbolOop field_name, symbolOop field_sig, bool is_method);
104
105 void verify_cp_index(constantPoolHandle cp, int index, TRAPS);
106 void verify_cp_type(
107 int index, constantPoolHandle cp, unsigned int types, TRAPS);
108 void verify_cp_class_type(int index, constantPoolHandle cp, TRAPS);
109
110 u2 verify_stackmap_table(
111 u2 stackmap_index, u2 bci, StackMapFrame* current_frame,
112 StackMapTable* stackmap_table, bool no_control_flow, TRAPS);
113
114 void verify_exception_handler_targets(
115 u2 bci, bool this_uninit, StackMapFrame* current_frame,
116 StackMapTable* stackmap_table, TRAPS);
117
118 void verify_ldc(
119 int opcode, u2 index, StackMapFrame *current_frame,
120 constantPoolHandle cp, u2 bci, TRAPS);
121
122 void verify_switch(
123 RawBytecodeStream* bcs, u4 code_length, char* code_data,
124 StackMapFrame* current_frame, StackMapTable* stackmap_table, TRAPS);
125
126 void verify_field_instructions(
127 RawBytecodeStream* bcs, StackMapFrame* current_frame,
128 constantPoolHandle cp, TRAPS);
129
130 void verify_invoke_init(
131 RawBytecodeStream* bcs, VerificationType ref_class_type,
132 StackMapFrame* current_frame, u4 code_length, bool* this_uninit,
133 constantPoolHandle cp, TRAPS);
134
135 void verify_invoke_instructions(
136 RawBytecodeStream* bcs, u4 code_length, StackMapFrame* current_frame,
137 bool* this_uninit, VerificationType return_type,
138 constantPoolHandle cp, TRAPS);
139
140 VerificationType get_newarray_type(u2 index, u2 bci, TRAPS);
141 void verify_anewarray(
142 u2 index, constantPoolHandle cp, StackMapFrame* current_frame, TRAPS);
143 void verify_return_value(
144 VerificationType return_type, VerificationType type, u2 offset, TRAPS);
145
146 void verify_iload (u2 index, StackMapFrame* current_frame, TRAPS);
147 void verify_lload (u2 index, StackMapFrame* current_frame, TRAPS);
148 void verify_fload (u2 index, StackMapFrame* current_frame, TRAPS);
149 void verify_dload (u2 index, StackMapFrame* current_frame, TRAPS);
150 void verify_aload (u2 index, StackMapFrame* current_frame, TRAPS);
151 void verify_istore(u2 index, StackMapFrame* current_frame, TRAPS);
152 void verify_lstore(u2 index, StackMapFrame* current_frame, TRAPS);
153 void verify_fstore(u2 index, StackMapFrame* current_frame, TRAPS);
154 void verify_dstore(u2 index, StackMapFrame* current_frame, TRAPS);
155 void verify_astore(u2 index, StackMapFrame* current_frame, TRAPS);
156 void verify_iinc (u2 index, StackMapFrame* current_frame, TRAPS);
157
158 bool name_in_supers(symbolOop ref_name, instanceKlassHandle current);
159
160 instanceKlassHandle _klass; // the class being verified
161 methodHandle _method; // current method being verified
162 VerificationType _this_type; // the verification type of the current class
163
164 // Some recursive calls from the verifier to the name resolver
165 // can cause the current class to be re-verified and rewritten.
166 // If this happens, the original verification should not continue,
167 // because constant pool indexes will have changed.
168 // The rewriter is preceded by the verifier. If the verifier throws
169 // an error, rewriting is prevented. Also, rewriting always precedes
170 // bytecode execution or compilation. Thus, is_rewritten implies
171 // that a class has been verified and prepared for execution.
172 bool was_recursively_verified() { return _klass->is_rewritten(); }
173
174 public:
175 enum {
176 BYTECODE_OFFSET = 1,
177 NEW_OFFSET = 2
178 };
179
180 // constructor
181 ClassVerifier(instanceKlassHandle klass, char* msg, size_t msg_len, TRAPS);
182
183 // destructor
184 ~ClassVerifier();
185
186 Thread* thread() { return _thread; }
187 methodHandle method() { return _method; }
188 instanceKlassHandle current_class() const { return _klass; }
189 VerificationType current_type() const { return _this_type; }
190
191 // Verifies the class. If a verify or class file format error occurs,
192 // the '_exception_name' symbols will set to the exception name and
193 // the message_buffer will be filled in with the exception message.
194 void verify_class(TRAPS);
195
196 // Return status modes
197 symbolHandle result() const { return _exception_type; }
198 bool has_error() const { return !(result().is_null()); }
199
200 // Called when verify or class format errors are encountered.
201 // May throw an exception based upon the mode.
202 void verify_error(u2 offset, const char* fmt, ...);
203 void verify_error(const char* fmt, ...);
204 void class_format_error(const char* fmt, ...);
205 void format_error_message(const char* fmt, int offset, va_list args);
206
207 klassOop load_class(symbolHandle name, TRAPS);
208
209 int change_sig_to_verificationType(
210 SignatureStream* sig_type, VerificationType* inference_type, TRAPS);
211
212 VerificationType cp_index_to_type(int index, constantPoolHandle cp, TRAPS) {
213 return VerificationType::reference_type(
214 symbolHandle(THREAD, cp->klass_name_at(index)));
215 }
216
217 static bool _verify_verbose; // for debugging
218 };
219
220 inline int ClassVerifier::change_sig_to_verificationType(
221 SignatureStream* sig_type, VerificationType* inference_type, TRAPS) {
222 BasicType bt = sig_type->type();
223 switch (bt) {
224 case T_OBJECT:
225 case T_ARRAY:
226 {
227 symbolOop name = sig_type->as_symbol(CHECK_0);
228 *inference_type =
229 VerificationType::reference_type(symbolHandle(THREAD, name));
230 return 1;
231 }
232 case T_LONG:
233 *inference_type = VerificationType::long_type();
234 *++inference_type = VerificationType::long2_type();
235 return 2;
236 case T_DOUBLE:
237 *inference_type = VerificationType::double_type();
238 *++inference_type = VerificationType::double2_type();
239 return 2;
240 case T_INT:
241 case T_BOOLEAN:
242 case T_BYTE:
243 case T_CHAR:
244 case T_SHORT:
245 *inference_type = VerificationType::integer_type();
246 return 1;
247 case T_FLOAT:
248 *inference_type = VerificationType::float_type();
249 return 1;
250 default:
251 ShouldNotReachHere();
252 return 1;
253 }
254 }