1 /* 2 * Copyright (c) 1998, 2013, 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 #ifndef SHARE_VM_CLASSFILE_VERIFIER_HPP 26 #define SHARE_VM_CLASSFILE_VERIFIER_HPP 27 28 #include "classfile/verificationType.hpp" 29 #include "memory/gcLocker.hpp" 30 #include "oops/klass.hpp" 31 #include "oops/method.hpp" 32 #include "runtime/handles.hpp" 33 #include "utilities/exceptions.hpp" 34 35 // The verifier class 36 class Verifier : AllStatic { 37 public: 38 enum { 39 STRICTER_ACCESS_CTRL_CHECK_VERSION = 49, 40 STACKMAP_ATTRIBUTE_MAJOR_VERSION = 50, 41 INVOKEDYNAMIC_MAJOR_VERSION = 51, 42 NO_RELAX_ACCESS_CTRL_CHECK_VERSION = 52 43 }; 44 typedef enum { ThrowException, NoException } Mode; 45 46 /** 47 * Verify the bytecodes for a class. If 'throw_exception' is true 48 * then the appropriate VerifyError or ClassFormatError will be thrown. 49 * Otherwise, no exception is thrown and the return indicates the 50 * error. 51 */ 52 static bool verify(instanceKlassHandle klass, Mode mode, bool should_verify_class, TRAPS); 53 54 // Return false if the class is loaded by the bootstrap loader, 55 // or if defineClass was called requesting skipping verification 56 // -Xverify:all/none override this value 57 static bool should_verify_for(oop class_loader, bool should_verify_class); 58 59 // Relax certain verifier checks to enable some broken 1.1 apps to run on 1.2. 60 static bool relax_verify_for(oop class_loader); 61 62 private: 63 static bool is_eligible_for_verification(instanceKlassHandle klass, bool should_verify_class); 64 static Symbol* inference_verify( 65 instanceKlassHandle klass, char* msg, size_t msg_len, TRAPS); 66 }; 67 68 class RawBytecodeStream; 69 class StackMapFrame; 70 class StackMapTable; 71 72 // Summary of verifier's memory usage: 73 // StackMapTable is stack allocated. 74 // StackMapFrame are resource allocated. There is only one ResourceMark 75 // for each class verification, which is created at the top level. 76 // There is one mutable StackMapFrame (current_frame) which is updated 77 // by abstract bytecode interpretation. frame_in_exception_handler() returns 78 // a frame that has a mutable one-item stack (ready for pushing the 79 // catch type exception object). All the other StackMapFrame's 80 // are immutable (including their locals and stack arrays) after 81 // their constructions. 82 // locals/stack arrays in StackMapFrame are resource allocated. 83 // locals/stack arrays can be shared between StackMapFrame's, except 84 // the mutable StackMapFrame (current_frame). 85 86 // These macros are used similarly to CHECK macros but also check 87 // the status of the verifier and return if that has an error. 88 #define CHECK_VERIFY(verifier) \ 89 CHECK); if ((verifier)->has_error()) return; ((void)0 90 #define CHECK_VERIFY_(verifier, result) \ 91 CHECK_(result)); if ((verifier)->has_error()) return (result); ((void)0 92 93 class TypeOrigin VALUE_OBJ_CLASS_SPEC { 94 private: 95 typedef enum { 96 CF_LOCALS, // Comes from the current frame locals 97 CF_STACK, // Comes from the current frame expression stack 98 SM_LOCALS, // Comes from stackmap locals 99 SM_STACK, // Comes from stackmap expression stack 100 CONST_POOL, // Comes from the constant pool 101 SIG, // Comes from method signature 102 IMPLICIT, // Comes implicitly from code or context 103 BAD_INDEX, // No type, but the index is bad 104 FRAME_ONLY, // No type, context just contains the frame 105 NONE 106 } Origin; 107 108 Origin _origin; 109 u2 _index; // local, stack, or constant pool index 110 StackMapFrame* _frame; // source frame if CF or SM 111 VerificationType _type; // The actual type 112 113 TypeOrigin( 114 Origin origin, u2 index, StackMapFrame* frame, VerificationType type) 115 : _origin(origin), _index(index), _frame(frame), _type(type) {} 116 117 public: 118 TypeOrigin() : _origin(NONE), _index(0), _frame(NULL) {} 119 120 static TypeOrigin null(); 121 static TypeOrigin local(u2 index, StackMapFrame* frame); 122 static TypeOrigin stack(u2 index, StackMapFrame* frame); 123 static TypeOrigin sm_local(u2 index, StackMapFrame* frame); 124 static TypeOrigin sm_stack(u2 index, StackMapFrame* frame); 125 static TypeOrigin cp(u2 index, VerificationType vt); 126 static TypeOrigin signature(VerificationType vt); 127 static TypeOrigin bad_index(u2 index); 128 static TypeOrigin implicit(VerificationType t); 129 static TypeOrigin frame(StackMapFrame* frame); 130 131 void reset_frame(); 132 void details(outputStream* ss) const; 133 void print_frame(outputStream* ss) const; 134 const StackMapFrame* frame() const { return _frame; } 135 bool is_valid() const { return _origin != NONE; } 136 u2 index() const { return _index; } 137 138 #ifdef ASSERT 139 void print_on(outputStream* str) const; 140 #endif 141 }; 142 143 class ErrorContext VALUE_OBJ_CLASS_SPEC { 144 private: 145 typedef enum { 146 INVALID_BYTECODE, // There was a problem with the bytecode 147 WRONG_TYPE, // Type value was not as expected 148 FLAGS_MISMATCH, // Frame flags are not assignable 149 BAD_CP_INDEX, // Invalid constant pool index 150 BAD_LOCAL_INDEX, // Invalid local index 151 LOCALS_SIZE_MISMATCH, // Frames have differing local counts 152 STACK_SIZE_MISMATCH, // Frames have different stack sizes 153 STACK_OVERFLOW, // Attempt to push onto a full expression stack 154 STACK_UNDERFLOW, // Attempt to pop and empty expression stack 155 MISSING_STACKMAP, // No stackmap for this location and there should be 156 BAD_STACKMAP, // Format error in stackmap 157 NO_FAULT, // No error 158 UNKNOWN 159 } FaultType; 160 161 int _bci; 162 FaultType _fault; 163 TypeOrigin _type; 164 TypeOrigin _expected; 165 166 ErrorContext(int bci, FaultType fault) : 167 _bci(bci), _fault(fault) {} 168 ErrorContext(int bci, FaultType fault, TypeOrigin type) : 169 _bci(bci), _fault(fault), _type(type) {} 170 ErrorContext(int bci, FaultType fault, TypeOrigin type, TypeOrigin exp) : 171 _bci(bci), _fault(fault), _type(type), _expected(exp) {} 172 173 public: 174 ErrorContext() : _bci(-1), _fault(NO_FAULT) {} 175 176 static ErrorContext bad_code(u2 bci) { 177 return ErrorContext(bci, INVALID_BYTECODE); 178 } 179 static ErrorContext bad_type(u2 bci, TypeOrigin type) { 180 return ErrorContext(bci, WRONG_TYPE, type); 181 } 182 static ErrorContext bad_type(u2 bci, TypeOrigin type, TypeOrigin exp) { 183 return ErrorContext(bci, WRONG_TYPE, type, exp); 184 } 185 static ErrorContext bad_flags(u2 bci, StackMapFrame* frame) { 186 return ErrorContext(bci, FLAGS_MISMATCH, TypeOrigin::frame(frame)); 187 } 188 static ErrorContext bad_flags(u2 bci, StackMapFrame* cur, StackMapFrame* sm) { 189 return ErrorContext(bci, FLAGS_MISMATCH, 190 TypeOrigin::frame(cur), TypeOrigin::frame(sm)); 191 } 192 static ErrorContext bad_cp_index(u2 bci, u2 index) { 193 return ErrorContext(bci, BAD_CP_INDEX, TypeOrigin::bad_index(index)); 194 } 195 static ErrorContext bad_local_index(u2 bci, u2 index) { 196 return ErrorContext(bci, BAD_LOCAL_INDEX, TypeOrigin::bad_index(index)); 197 } 198 static ErrorContext locals_size_mismatch( 199 u2 bci, StackMapFrame* frame0, StackMapFrame* frame1) { 200 return ErrorContext(bci, LOCALS_SIZE_MISMATCH, 201 TypeOrigin::frame(frame0), TypeOrigin::frame(frame1)); 202 } 203 static ErrorContext stack_size_mismatch( 204 u2 bci, StackMapFrame* frame0, StackMapFrame* frame1) { 205 return ErrorContext(bci, STACK_SIZE_MISMATCH, 206 TypeOrigin::frame(frame0), TypeOrigin::frame(frame1)); 207 } 208 static ErrorContext stack_overflow(u2 bci, StackMapFrame* frame) { 209 return ErrorContext(bci, STACK_OVERFLOW, TypeOrigin::frame(frame)); 210 } 211 static ErrorContext stack_underflow(u2 bci, StackMapFrame* frame) { 212 return ErrorContext(bci, STACK_UNDERFLOW, TypeOrigin::frame(frame)); 213 } 214 static ErrorContext missing_stackmap(u2 bci) { 215 return ErrorContext(bci, MISSING_STACKMAP); 216 } 217 static ErrorContext bad_stackmap(int index, StackMapFrame* frame) { 218 return ErrorContext(0, BAD_STACKMAP, TypeOrigin::frame(frame)); 219 } 220 221 bool is_valid() const { return _fault != NO_FAULT; } 222 int bci() const { return _bci; } 223 224 void reset_frames() { 225 _type.reset_frame(); 226 _expected.reset_frame(); 227 } 228 229 void details(outputStream* ss, const Method* method) const; 230 231 #ifdef ASSERT 232 void print_on(outputStream* str) const { 233 str->print("error_context(%d, %d,", _bci, _fault); 234 _type.print_on(str); 235 str->print(","); 236 _expected.print_on(str); 237 str->print(")"); 238 } 239 #endif 240 241 private: 242 void location_details(outputStream* ss, const Method* method) const; 243 void reason_details(outputStream* ss) const; 244 void frame_details(outputStream* ss) const; 245 void bytecode_details(outputStream* ss, const Method* method) const; 246 void handler_details(outputStream* ss, const Method* method) const; 247 void stackmap_details(outputStream* ss, const Method* method) const; 248 }; 249 250 // A new instance of this class is created for each class being verified 251 class ClassVerifier : public StackObj { 252 private: 253 Thread* _thread; 254 GrowableArray<Symbol*>* _symbols; // keep a list of symbols created 255 256 Symbol* _exception_type; 257 char* _message; 258 259 ErrorContext _error_context; // contains information about an error 260 261 void verify_method(methodHandle method, TRAPS); 262 char* generate_code_data(methodHandle m, u4 code_length, TRAPS); 263 void verify_exception_handler_table(u4 code_length, char* code_data, 264 int& min, int& max, TRAPS); 265 void verify_local_variable_table(u4 code_length, char* code_data, TRAPS); 266 267 VerificationType cp_ref_index_to_type( 268 int index, constantPoolHandle cp, TRAPS) { 269 return cp_index_to_type(cp->klass_ref_index_at(index), cp, THREAD); 270 } 271 272 bool is_protected_access( 273 instanceKlassHandle this_class, Klass* target_class, 274 Symbol* field_name, Symbol* field_sig, bool is_method); 275 276 void verify_cp_index(u2 bci, constantPoolHandle cp, int index, TRAPS); 277 void verify_cp_type(u2 bci, int index, constantPoolHandle cp, 278 unsigned int types, TRAPS); 279 void verify_cp_class_type(u2 bci, int index, constantPoolHandle cp, TRAPS); 280 281 u2 verify_stackmap_table( 282 u2 stackmap_index, u2 bci, StackMapFrame* current_frame, 283 StackMapTable* stackmap_table, bool no_control_flow, TRAPS); 284 285 void verify_exception_handler_targets( 286 u2 bci, bool this_uninit, StackMapFrame* current_frame, 287 StackMapTable* stackmap_table, TRAPS); 288 289 void verify_ldc( 290 int opcode, u2 index, StackMapFrame *current_frame, 291 constantPoolHandle cp, u2 bci, TRAPS); 292 293 void verify_switch( 294 RawBytecodeStream* bcs, u4 code_length, char* code_data, 295 StackMapFrame* current_frame, StackMapTable* stackmap_table, TRAPS); 296 297 void verify_field_instructions( 298 RawBytecodeStream* bcs, StackMapFrame* current_frame, 299 constantPoolHandle cp, TRAPS); 300 301 void verify_invoke_init( 302 RawBytecodeStream* bcs, u2 ref_index, VerificationType ref_class_type, 303 StackMapFrame* current_frame, u4 code_length, bool* this_uninit, 304 constantPoolHandle cp, TRAPS); 305 306 void verify_invoke_instructions( 307 RawBytecodeStream* bcs, u4 code_length, StackMapFrame* current_frame, 308 bool* this_uninit, VerificationType return_type, 309 constantPoolHandle cp, TRAPS); 310 311 VerificationType get_newarray_type(u2 index, u2 bci, TRAPS); 312 void verify_anewarray(u2 bci, u2 index, constantPoolHandle cp, 313 StackMapFrame* current_frame, TRAPS); 314 void verify_return_value( 315 VerificationType return_type, VerificationType type, u2 offset, 316 StackMapFrame* current_frame, TRAPS); 317 318 void verify_iload (u2 index, StackMapFrame* current_frame, TRAPS); 319 void verify_lload (u2 index, StackMapFrame* current_frame, TRAPS); 320 void verify_fload (u2 index, StackMapFrame* current_frame, TRAPS); 321 void verify_dload (u2 index, StackMapFrame* current_frame, TRAPS); 322 void verify_aload (u2 index, StackMapFrame* current_frame, TRAPS); 323 void verify_istore(u2 index, StackMapFrame* current_frame, TRAPS); 324 void verify_lstore(u2 index, StackMapFrame* current_frame, TRAPS); 325 void verify_fstore(u2 index, StackMapFrame* current_frame, TRAPS); 326 void verify_dstore(u2 index, StackMapFrame* current_frame, TRAPS); 327 void verify_astore(u2 index, StackMapFrame* current_frame, TRAPS); 328 void verify_iinc (u2 index, StackMapFrame* current_frame, TRAPS); 329 330 bool name_in_supers(Symbol* ref_name, instanceKlassHandle current); 331 332 VerificationType object_type() const; 333 334 instanceKlassHandle _klass; // the class being verified 335 methodHandle _method; // current method being verified 336 VerificationType _this_type; // the verification type of the current class 337 338 // Some recursive calls from the verifier to the name resolver 339 // can cause the current class to be re-verified and rewritten. 340 // If this happens, the original verification should not continue, 341 // because constant pool indexes will have changed. 342 // The rewriter is preceded by the verifier. If the verifier throws 343 // an error, rewriting is prevented. Also, rewriting always precedes 344 // bytecode execution or compilation. Thus, is_rewritten implies 345 // that a class has been verified and prepared for execution. 346 bool was_recursively_verified() { return _klass->is_rewritten(); } 347 348 public: 349 enum { 350 BYTECODE_OFFSET = 1, 351 NEW_OFFSET = 2 352 }; 353 354 // constructor 355 ClassVerifier(instanceKlassHandle klass, TRAPS); 356 357 // destructor 358 ~ClassVerifier(); 359 360 Thread* thread() { return _thread; } 361 methodHandle method() { return _method; } 362 instanceKlassHandle current_class() const { return _klass; } 363 VerificationType current_type() const { return _this_type; } 364 365 // Verifies the class. If a verify or class file format error occurs, 366 // the '_exception_name' symbols will set to the exception name and 367 // the message_buffer will be filled in with the exception message. 368 void verify_class(TRAPS); 369 370 // Return status modes 371 Symbol* result() const { return _exception_type; } 372 bool has_error() const { return result() != NULL; } 373 char* exception_message() { 374 stringStream ss; 375 ss.print(_message); 376 _error_context.details(&ss, _method()); 377 return ss.as_string(); 378 } 379 380 // Called when verify or class format errors are encountered. 381 // May throw an exception based upon the mode. 382 void verify_error(ErrorContext ctx, const char* fmt, ...); 383 void class_format_error(const char* fmt, ...); 384 385 Klass* load_class(Symbol* name, TRAPS); 386 387 int change_sig_to_verificationType( 388 SignatureStream* sig_type, VerificationType* inference_type, TRAPS); 389 390 VerificationType cp_index_to_type(int index, constantPoolHandle cp, TRAPS) { 391 return VerificationType::reference_type(cp->klass_name_at(index)); 392 } 393 394 // Keep a list of temporary symbols created during verification because 395 // their reference counts need to be decrememented when the verifier object 396 // goes out of scope. Since these symbols escape the scope in which they're 397 // created, we can't use a TempNewSymbol. 398 Symbol* create_temporary_symbol( 399 const Symbol* s, int begin, int end, TRAPS); 400 Symbol* create_temporary_symbol(const char *s, int length, TRAPS); 401 402 TypeOrigin ref_ctx(const char* str, TRAPS); 403 }; 404 405 inline int ClassVerifier::change_sig_to_verificationType( 406 SignatureStream* sig_type, VerificationType* inference_type, TRAPS) { 407 BasicType bt = sig_type->type(); 408 switch (bt) { 409 case T_OBJECT: 410 case T_ARRAY: 411 { 412 Symbol* name = sig_type->as_symbol(CHECK_0); 413 // Create another symbol to save as signature stream unreferences 414 // this symbol. 415 Symbol* name_copy = 416 create_temporary_symbol(name, 0, name->utf8_length(), CHECK_0); 417 assert(name_copy == name, "symbols don't match"); 418 *inference_type = 419 VerificationType::reference_type(name_copy); 420 return 1; 421 } 422 case T_LONG: 423 *inference_type = VerificationType::long_type(); 424 *++inference_type = VerificationType::long2_type(); 425 return 2; 426 case T_DOUBLE: 427 *inference_type = VerificationType::double_type(); 428 *++inference_type = VerificationType::double2_type(); 429 return 2; 430 case T_INT: 431 case T_BOOLEAN: 432 case T_BYTE: 433 case T_CHAR: 434 case T_SHORT: 435 *inference_type = VerificationType::integer_type(); 436 return 1; 437 case T_FLOAT: 438 *inference_type = VerificationType::float_type(); 439 return 1; 440 default: 441 ShouldNotReachHere(); 442 return 1; 443 } 444 } 445 446 #endif // SHARE_VM_CLASSFILE_VERIFIER_HPP