1 /* 2 * Copyright (c) 1998, 2014, 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/growableArray.hpp" 34 #include "utilities/exceptions.hpp" 35 36 // The verifier class 37 class Verifier : AllStatic { 38 public: 39 enum { 40 STRICTER_ACCESS_CTRL_CHECK_VERSION = 49, 41 STACKMAP_ATTRIBUTE_MAJOR_VERSION = 50, 42 INVOKEDYNAMIC_MAJOR_VERSION = 51, 43 NO_RELAX_ACCESS_CTRL_CHECK_VERSION = 52 44 }; 45 typedef enum { ThrowException, NoException } Mode; 46 47 /** 48 * Verify the bytecodes for a class. If 'throw_exception' is true 49 * then the appropriate VerifyError or ClassFormatError will be thrown. 50 * Otherwise, no exception is thrown and the return indicates the 51 * error. 52 */ 53 static bool verify(instanceKlassHandle klass, Mode mode, bool should_verify_class, TRAPS); 54 55 // Return false if the class is loaded by the bootstrap loader, 56 // or if defineClass was called requesting skipping verification 57 // -Xverify:all/none override this value 58 static bool should_verify_for(oop class_loader, bool should_verify_class); 59 60 // Relax certain verifier checks to enable some broken 1.1 apps to run on 1.2. 61 static bool relax_verify_for(oop class_loader); 62 63 private: 64 static bool is_eligible_for_verification(instanceKlassHandle klass, bool should_verify_class); 65 static Symbol* inference_verify( 66 instanceKlassHandle klass, char* msg, size_t msg_len, TRAPS); 67 }; 68 69 class RawBytecodeStream; 70 class StackMapFrame; 71 class StackMapTable; 72 73 // Summary of verifier's memory usage: 74 // StackMapTable is stack allocated. 75 // StackMapFrame are resource allocated. There is only one ResourceMark 76 // for each class verification, which is created at the top level. 77 // There is one mutable StackMapFrame (current_frame) which is updated 78 // by abstract bytecode interpretation. frame_in_exception_handler() returns 79 // a frame that has a mutable one-item stack (ready for pushing the 80 // catch type exception object). All the other StackMapFrame's 81 // are immutable (including their locals and stack arrays) after 82 // their constructions. 83 // locals/stack arrays in StackMapFrame are resource allocated. 84 // locals/stack arrays can be shared between StackMapFrame's, except 85 // the mutable StackMapFrame (current_frame). 86 87 // These macros are used similarly to CHECK macros but also check 88 // the status of the verifier and return if that has an error. 89 #define CHECK_VERIFY(verifier) \ 90 CHECK); if ((verifier)->has_error()) return; ((void)0 91 #define CHECK_VERIFY_(verifier, result) \ 92 CHECK_(result)); if ((verifier)->has_error()) return (result); ((void)0 93 94 class TypeOrigin VALUE_OBJ_CLASS_SPEC { 95 private: 96 typedef enum { 97 CF_LOCALS, // Comes from the current frame locals 98 CF_STACK, // Comes from the current frame expression stack 99 SM_LOCALS, // Comes from stackmap locals 100 SM_STACK, // Comes from stackmap expression stack 101 CONST_POOL, // Comes from the constant pool 102 SIG, // Comes from method signature 103 IMPLICIT, // Comes implicitly from code or context 104 BAD_INDEX, // No type, but the index is bad 105 FRAME_ONLY, // No type, context just contains the frame 106 NONE 107 } Origin; 108 109 Origin _origin; 110 u2 _index; // local, stack, or constant pool index 111 StackMapFrame* _frame; // source frame if CF or SM 112 VerificationType _type; // The actual type 113 114 TypeOrigin( 115 Origin origin, u2 index, StackMapFrame* frame, VerificationType type) 116 : _origin(origin), _index(index), _frame(frame), _type(type) {} 117 118 public: 119 TypeOrigin() : _origin(NONE), _index(0), _frame(NULL) {} 120 121 static TypeOrigin null(); 122 static TypeOrigin local(u2 index, StackMapFrame* frame); 123 static TypeOrigin stack(u2 index, StackMapFrame* frame); 124 static TypeOrigin sm_local(u2 index, StackMapFrame* frame); 125 static TypeOrigin sm_stack(u2 index, StackMapFrame* frame); 126 static TypeOrigin cp(u2 index, VerificationType vt); 127 static TypeOrigin signature(VerificationType vt); 128 static TypeOrigin bad_index(u2 index); 129 static TypeOrigin implicit(VerificationType t); 130 static TypeOrigin frame(StackMapFrame* frame); 131 132 void reset_frame(); 133 void details(outputStream* ss) const; 134 void print_frame(outputStream* ss) const; 135 const StackMapFrame* frame() const { return _frame; } 136 bool is_valid() const { return _origin != NONE; } 137 u2 index() const { return _index; } 138 139 #ifdef ASSERT 140 void print_on(outputStream* str) const; 141 #endif 142 }; 143 144 class ErrorContext VALUE_OBJ_CLASS_SPEC { 145 private: 146 typedef enum { 147 INVALID_BYTECODE, // There was a problem with the bytecode 148 WRONG_TYPE, // Type value was not as expected 149 FLAGS_MISMATCH, // Frame flags are not assignable 150 BAD_CP_INDEX, // Invalid constant pool index 151 BAD_LOCAL_INDEX, // Invalid local index 152 LOCALS_SIZE_MISMATCH, // Frames have differing local counts 153 STACK_SIZE_MISMATCH, // Frames have different stack sizes 154 STACK_OVERFLOW, // Attempt to push onto a full expression stack 155 STACK_UNDERFLOW, // Attempt to pop and empty expression stack 156 MISSING_STACKMAP, // No stackmap for this location and there should be 157 BAD_STACKMAP, // Format error in stackmap 158 NO_FAULT, // No error 159 UNKNOWN 160 } FaultType; 161 162 int _bci; 163 FaultType _fault; 164 TypeOrigin _type; 165 TypeOrigin _expected; 166 167 ErrorContext(int bci, FaultType fault) : 168 _bci(bci), _fault(fault) {} 169 ErrorContext(int bci, FaultType fault, TypeOrigin type) : 170 _bci(bci), _fault(fault), _type(type) {} 171 ErrorContext(int bci, FaultType fault, TypeOrigin type, TypeOrigin exp) : 172 _bci(bci), _fault(fault), _type(type), _expected(exp) {} 173 174 public: 175 ErrorContext() : _bci(-1), _fault(NO_FAULT) {} 176 177 static ErrorContext bad_code(u2 bci) { 178 return ErrorContext(bci, INVALID_BYTECODE); 179 } 180 static ErrorContext bad_type(u2 bci, TypeOrigin type) { 181 return ErrorContext(bci, WRONG_TYPE, type); 182 } 183 static ErrorContext bad_type(u2 bci, TypeOrigin type, TypeOrigin exp) { 184 return ErrorContext(bci, WRONG_TYPE, type, exp); 185 } 186 static ErrorContext bad_flags(u2 bci, StackMapFrame* frame) { 187 return ErrorContext(bci, FLAGS_MISMATCH, TypeOrigin::frame(frame)); 188 } 189 static ErrorContext bad_flags(u2 bci, StackMapFrame* cur, StackMapFrame* sm) { 190 return ErrorContext(bci, FLAGS_MISMATCH, 191 TypeOrigin::frame(cur), TypeOrigin::frame(sm)); 192 } 193 static ErrorContext bad_cp_index(u2 bci, u2 index) { 194 return ErrorContext(bci, BAD_CP_INDEX, TypeOrigin::bad_index(index)); 195 } 196 static ErrorContext bad_local_index(u2 bci, u2 index) { 197 return ErrorContext(bci, BAD_LOCAL_INDEX, TypeOrigin::bad_index(index)); 198 } 199 static ErrorContext locals_size_mismatch( 200 u2 bci, StackMapFrame* frame0, StackMapFrame* frame1) { 201 return ErrorContext(bci, LOCALS_SIZE_MISMATCH, 202 TypeOrigin::frame(frame0), TypeOrigin::frame(frame1)); 203 } 204 static ErrorContext stack_size_mismatch( 205 u2 bci, StackMapFrame* frame0, StackMapFrame* frame1) { 206 return ErrorContext(bci, STACK_SIZE_MISMATCH, 207 TypeOrigin::frame(frame0), TypeOrigin::frame(frame1)); 208 } 209 static ErrorContext stack_overflow(u2 bci, StackMapFrame* frame) { 210 return ErrorContext(bci, STACK_OVERFLOW, TypeOrigin::frame(frame)); 211 } 212 static ErrorContext stack_underflow(u2 bci, StackMapFrame* frame) { 213 return ErrorContext(bci, STACK_UNDERFLOW, TypeOrigin::frame(frame)); 214 } 215 static ErrorContext missing_stackmap(u2 bci) { 216 return ErrorContext(bci, MISSING_STACKMAP); 217 } 218 static ErrorContext bad_stackmap(int index, StackMapFrame* frame) { 219 return ErrorContext(0, BAD_STACKMAP, TypeOrigin::frame(frame)); 220 } 221 222 bool is_valid() const { return _fault != NO_FAULT; } 223 int bci() const { return _bci; } 224 225 void reset_frames() { 226 _type.reset_frame(); 227 _expected.reset_frame(); 228 } 229 230 void details(outputStream* ss, const Method* method) const; 231 232 #ifdef ASSERT 233 void print_on(outputStream* str) const { 234 str->print("error_context(%d, %d,", _bci, _fault); 235 _type.print_on(str); 236 str->print(","); 237 _expected.print_on(str); 238 str->print(")"); 239 } 240 #endif 241 242 private: 243 void location_details(outputStream* ss, const Method* method) const; 244 void reason_details(outputStream* ss) const; 245 void frame_details(outputStream* ss) const; 246 void bytecode_details(outputStream* ss, const Method* method) const; 247 void handler_details(outputStream* ss, const Method* method) const; 248 void stackmap_details(outputStream* ss, const Method* method) const; 249 }; 250 251 // A new instance of this class is created for each class being verified 252 class ClassVerifier : public StackObj { 253 private: 254 Thread* _thread; 255 GrowableArray<Symbol*>* _symbols; // keep a list of symbols created 256 257 Symbol* _exception_type; 258 char* _message; 259 260 ErrorContext _error_context; // contains information about an error 261 262 // Used to detect illegal jumps over calls to super() nd this() in ctors. 263 int32_t _furthest_jump; 264 265 void verify_method(methodHandle method, TRAPS); 266 char* generate_code_data(methodHandle m, u4 code_length, TRAPS); 267 void verify_exception_handler_table(u4 code_length, char* code_data, 268 int& min, int& max, TRAPS); 269 void verify_local_variable_table(u4 code_length, char* code_data, TRAPS); 270 271 VerificationType cp_ref_index_to_type( 272 int index, constantPoolHandle cp, TRAPS) { 273 return cp_index_to_type(cp->klass_ref_index_at(index), cp, THREAD); 274 } 275 276 bool is_protected_access( 277 instanceKlassHandle this_class, Klass* target_class, 278 Symbol* field_name, Symbol* field_sig, bool is_method); 279 280 void verify_cp_index(u2 bci, constantPoolHandle cp, int index, TRAPS); 281 void verify_cp_type(u2 bci, int index, constantPoolHandle cp, 282 unsigned int types, TRAPS); 283 void verify_cp_class_type(u2 bci, int index, constantPoolHandle cp, TRAPS); 284 285 u2 verify_stackmap_table( 286 u2 stackmap_index, u2 bci, StackMapFrame* current_frame, 287 StackMapTable* stackmap_table, bool no_control_flow, TRAPS); 288 289 void verify_exception_handler_targets( 290 u2 bci, bool this_uninit, StackMapFrame* current_frame, 291 StackMapTable* stackmap_table, TRAPS); 292 293 void verify_ldc( 294 int opcode, u2 index, StackMapFrame *current_frame, 295 constantPoolHandle cp, u2 bci, TRAPS); 296 297 void verify_switch( 298 RawBytecodeStream* bcs, u4 code_length, char* code_data, 299 StackMapFrame* current_frame, StackMapTable* stackmap_table, TRAPS); 300 301 void verify_field_instructions( 302 RawBytecodeStream* bcs, StackMapFrame* current_frame, 303 constantPoolHandle cp, TRAPS); 304 305 void verify_invoke_init( 306 RawBytecodeStream* bcs, u2 ref_index, VerificationType ref_class_type, 307 StackMapFrame* current_frame, u4 code_length, bool* this_uninit, 308 constantPoolHandle cp, TRAPS); 309 310 // Used by ends_in_athrow() to save bytecode intervals. 311 void push_bci_offsets(GrowableArray<u4> *bci_stack_ptr, 312 u4 start_offset, u4 end_offset) { 313 bci_stack_ptr->push(start_offset); 314 bci_stack_ptr->push(end_offset); 315 } 316 317 // Used by ends_in_athrow() to retrieve start of saved bytecode interval. 318 u4 pop_bci_start_offset(GrowableArray<u4> *bci_stack_ptr) { 319 assert(!bci_stack_ptr->is_empty(), "Stack should not be empty"); 320 assert(bci_stack_ptr->length() % 2 == 1, 321 "Stack should have odd number of entries"); 322 return bci_stack_ptr->pop(); 323 } 324 325 // Used by ends_in_athrow() to retrieve end of saved bytecode interval. 326 u4 pop_bci_end_offset(GrowableArray<u4> *bci_stack_ptr) { 327 assert(!bci_stack_ptr->is_empty(), "Stack should not be empty"); 328 assert(bci_stack_ptr->length() % 2 == 0, 329 "Stack should have even number of entries"); 330 return bci_stack_ptr->pop(); 331 } 332 333 // Returns true if all paths thru the specified bytecode stream end in athrow. 334 bool ends_in_athrow(u4 start_bc_offset, u4 end_bc_offset); 335 336 void verify_invoke_instructions( 337 RawBytecodeStream* bcs, u4 code_length, StackMapFrame* current_frame, 338 bool* this_uninit, VerificationType return_type, 339 constantPoolHandle cp, TRAPS); 340 341 VerificationType get_newarray_type(u2 index, u2 bci, TRAPS); 342 void verify_anewarray(u2 bci, u2 index, constantPoolHandle cp, 343 StackMapFrame* current_frame, TRAPS); 344 void verify_return_value( 345 VerificationType return_type, VerificationType type, u2 offset, 346 StackMapFrame* current_frame, TRAPS); 347 348 void verify_iload (u2 index, StackMapFrame* current_frame, TRAPS); 349 void verify_lload (u2 index, StackMapFrame* current_frame, TRAPS); 350 void verify_fload (u2 index, StackMapFrame* current_frame, TRAPS); 351 void verify_dload (u2 index, StackMapFrame* current_frame, TRAPS); 352 void verify_aload (u2 index, StackMapFrame* current_frame, TRAPS); 353 void verify_istore(u2 index, StackMapFrame* current_frame, TRAPS); 354 void verify_lstore(u2 index, StackMapFrame* current_frame, TRAPS); 355 void verify_fstore(u2 index, StackMapFrame* current_frame, TRAPS); 356 void verify_dstore(u2 index, StackMapFrame* current_frame, TRAPS); 357 void verify_astore(u2 index, StackMapFrame* current_frame, TRAPS); 358 void verify_iinc (u2 index, StackMapFrame* current_frame, TRAPS); 359 360 bool name_in_supers(Symbol* ref_name, instanceKlassHandle current); 361 362 VerificationType object_type() const; 363 364 instanceKlassHandle _klass; // the class being verified 365 methodHandle _method; // current method being verified 366 VerificationType _this_type; // the verification type of the current class 367 368 // Some recursive calls from the verifier to the name resolver 369 // can cause the current class to be re-verified and rewritten. 370 // If this happens, the original verification should not continue, 371 // because constant pool indexes will have changed. 372 // The rewriter is preceded by the verifier. If the verifier throws 373 // an error, rewriting is prevented. Also, rewriting always precedes 374 // bytecode execution or compilation. Thus, is_rewritten implies 375 // that a class has been verified and prepared for execution. 376 bool was_recursively_verified() { return _klass->is_rewritten(); } 377 378 bool is_same_or_direct_interface(instanceKlassHandle klass, 379 VerificationType klass_type, VerificationType ref_class_type); 380 381 public: 382 enum { 383 BYTECODE_OFFSET = 1, 384 NEW_OFFSET = 2 385 }; 386 387 // constructor 388 ClassVerifier(instanceKlassHandle klass, TRAPS); 389 390 // destructor 391 ~ClassVerifier(); 392 393 Thread* thread() { return _thread; } 394 methodHandle method() { return _method; } 395 instanceKlassHandle current_class() const { return _klass; } 396 VerificationType current_type() const { return _this_type; } 397 398 // Verifies the class. If a verify or class file format error occurs, 399 // the '_exception_name' symbols will set to the exception name and 400 // the message_buffer will be filled in with the exception message. 401 void verify_class(TRAPS); 402 403 // Return status modes 404 Symbol* result() const { return _exception_type; } 405 bool has_error() const { return result() != NULL; } 406 char* exception_message() { 407 stringStream ss; 408 ss.print("%s", _message); 409 _error_context.details(&ss, _method()); 410 return ss.as_string(); 411 } 412 413 // Called when verify or class format errors are encountered. 414 // May throw an exception based upon the mode. 415 void verify_error(ErrorContext ctx, const char* fmt, ...) ATTRIBUTE_PRINTF(3, 4); 416 void class_format_error(const char* fmt, ...) ATTRIBUTE_PRINTF(2, 3); 417 418 Klass* load_class(Symbol* name, TRAPS); 419 420 int change_sig_to_verificationType( 421 SignatureStream* sig_type, VerificationType* inference_type, TRAPS); 422 423 VerificationType cp_index_to_type(int index, constantPoolHandle cp, TRAPS) { 424 return VerificationType::reference_type(cp->klass_name_at(index)); 425 } 426 427 // Keep a list of temporary symbols created during verification because 428 // their reference counts need to be decrememented when the verifier object 429 // goes out of scope. Since these symbols escape the scope in which they're 430 // created, we can't use a TempNewSymbol. 431 Symbol* create_temporary_symbol( 432 const Symbol* s, int begin, int end, TRAPS); 433 Symbol* create_temporary_symbol(const char *s, int length, TRAPS); 434 435 TypeOrigin ref_ctx(const char* str, TRAPS); 436 437 // Keep track of the furthest branch done in a method to make sure that 438 // there are no branches over calls to super() or this() from inside of 439 // a constructor. 440 int32_t furthest_jump() { return _furthest_jump; } 441 442 void set_furthest_jump(int32_t target) { 443 _furthest_jump = target; 444 } 445 446 void update_furthest_jump(int32_t target) { 447 if (target > _furthest_jump) _furthest_jump = target; 448 } 449 450 }; 451 452 inline int ClassVerifier::change_sig_to_verificationType( 453 SignatureStream* sig_type, VerificationType* inference_type, TRAPS) { 454 BasicType bt = sig_type->type(); 455 switch (bt) { 456 case T_OBJECT: 457 case T_ARRAY: 458 { 459 Symbol* name = sig_type->as_symbol(CHECK_0); 460 // Create another symbol to save as signature stream unreferences 461 // this symbol. 462 Symbol* name_copy = 463 create_temporary_symbol(name, 0, name->utf8_length(), CHECK_0); 464 assert(name_copy == name, "symbols don't match"); 465 *inference_type = 466 VerificationType::reference_type(name_copy); 467 return 1; 468 } 469 case T_LONG: 470 *inference_type = VerificationType::long_type(); 471 *++inference_type = VerificationType::long2_type(); 472 return 2; 473 case T_DOUBLE: 474 *inference_type = VerificationType::double_type(); 475 *++inference_type = VerificationType::double2_type(); 476 return 2; 477 case T_INT: 478 case T_BOOLEAN: 479 case T_BYTE: 480 case T_CHAR: 481 case T_SHORT: 482 *inference_type = VerificationType::integer_type(); 483 return 1; 484 case T_FLOAT: 485 *inference_type = VerificationType::float_type(); 486 return 1; 487 default: 488 ShouldNotReachHere(); 489 return 1; 490 } 491 } 492 493 #endif // SHARE_VM_CLASSFILE_VERIFIER_HPP