1 /* 2 * Copyright (c) 1998, 2018, 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 "oops/klass.hpp" 30 #include "oops/method.hpp" 31 #include "runtime/handles.hpp" 32 #include "utilities/exceptions.hpp" 33 #include "utilities/growableArray.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 DYNAMICCONSTANT_MAJOR_VERSION = 55 44 }; 45 46 // Verify the bytecodes for a class. 47 static bool verify(InstanceKlass* klass, bool should_verify_class, TRAPS); 48 49 static void log_end_verification(outputStream* st, const char* klassName, Symbol* exception_name, TRAPS); 50 51 // Return false if the class is loaded by the bootstrap loader, 52 // or if defineClass was called requesting skipping verification 53 // -Xverify:all/none override this value 54 static bool should_verify_for(oop class_loader, bool should_verify_class); 55 56 // Relax certain access checks to enable some broken 1.1 apps to run on 1.2. 57 static bool relax_access_for(oop class_loader); 58 59 // Print output for class+resolve 60 static void trace_class_resolution(Klass* resolve_class, InstanceKlass* verify_class); 61 62 private: 63 static bool is_eligible_for_verification(InstanceKlass* klass, bool should_verify_class); 64 static Symbol* inference_verify( 65 InstanceKlass* 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 { 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 { 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(const methodHandle& method, TRAPS); 262 char* generate_code_data(const 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, const 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 InstanceKlass* this_class, Klass* target_class, 274 Symbol* field_name, Symbol* field_sig, bool is_method); 275 276 void verify_cp_index(u2 bci, const constantPoolHandle& cp, int index, TRAPS); 277 void verify_cp_type(u2 bci, int index, const constantPoolHandle& cp, 278 unsigned int types, TRAPS); 279 void verify_cp_class_type(u2 bci, int index, const 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 const 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 const constantPoolHandle& cp, bool allow_arrays, 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 in_try_block, 304 bool* this_uninit, const constantPoolHandle& cp, StackMapTable* stackmap_table, 305 TRAPS); 306 307 // Used by ends_in_athrow() to push all handlers that contain bci onto the 308 // handler_stack, if the handler has not already been pushed on the stack. 309 void push_handlers(ExceptionTable* exhandlers, 310 GrowableArray<u4>* handler_list, 311 GrowableArray<u4>* handler_stack, 312 u4 bci); 313 314 // Returns true if all paths starting with start_bc_offset end in athrow 315 // bytecode or loop. 316 bool ends_in_athrow(u4 start_bc_offset); 317 318 void verify_invoke_instructions( 319 RawBytecodeStream* bcs, u4 code_length, StackMapFrame* current_frame, 320 bool in_try_block, bool* this_uninit, VerificationType return_type, 321 const constantPoolHandle& cp, StackMapTable* stackmap_table, TRAPS); 322 323 VerificationType get_newarray_type(u2 index, u2 bci, TRAPS); 324 void verify_anewarray(u2 bci, u2 index, const constantPoolHandle& cp, 325 StackMapFrame* current_frame, TRAPS); 326 void verify_return_value( 327 VerificationType return_type, VerificationType type, u2 offset, 328 StackMapFrame* current_frame, TRAPS); 329 330 void verify_iload (u2 index, StackMapFrame* current_frame, TRAPS); 331 void verify_lload (u2 index, StackMapFrame* current_frame, TRAPS); 332 void verify_fload (u2 index, StackMapFrame* current_frame, TRAPS); 333 void verify_dload (u2 index, StackMapFrame* current_frame, TRAPS); 334 void verify_aload (u2 index, StackMapFrame* current_frame, TRAPS); 335 void verify_istore(u2 index, StackMapFrame* current_frame, TRAPS); 336 void verify_lstore(u2 index, StackMapFrame* current_frame, TRAPS); 337 void verify_fstore(u2 index, StackMapFrame* current_frame, TRAPS); 338 void verify_dstore(u2 index, StackMapFrame* current_frame, TRAPS); 339 void verify_astore(u2 index, StackMapFrame* current_frame, TRAPS); 340 void verify_iinc (u2 index, StackMapFrame* current_frame, TRAPS); 341 342 bool name_in_supers(Symbol* ref_name, InstanceKlass* current); 343 344 VerificationType object_type() const; 345 346 InstanceKlass* _klass; // the class being verified 347 methodHandle _method; // current method being verified 348 VerificationType _this_type; // the verification type of the current class 349 350 // Some recursive calls from the verifier to the name resolver 351 // can cause the current class to be re-verified and rewritten. 352 // If this happens, the original verification should not continue, 353 // because constant pool indexes will have changed. 354 // The rewriter is preceded by the verifier. If the verifier throws 355 // an error, rewriting is prevented. Also, rewriting always precedes 356 // bytecode execution or compilation. Thus, is_rewritten implies 357 // that a class has been verified and prepared for execution. 358 bool was_recursively_verified() { return _klass->is_rewritten(); } 359 360 bool is_same_or_direct_interface(InstanceKlass* klass, 361 VerificationType klass_type, VerificationType ref_class_type); 362 363 public: 364 enum { 365 BYTECODE_OFFSET = 1, 366 NEW_OFFSET = 2 367 }; 368 369 // constructor 370 ClassVerifier(InstanceKlass* klass, TRAPS); 371 372 // destructor 373 ~ClassVerifier(); 374 375 Thread* thread() { return _thread; } 376 const methodHandle& method() { return _method; } 377 InstanceKlass* current_class() const { return _klass; } 378 VerificationType current_type() const { return _this_type; } 379 380 // Verifies the class. If a verify or class file format error occurs, 381 // the '_exception_name' symbols will set to the exception name and 382 // the message_buffer will be filled in with the exception message. 383 void verify_class(TRAPS); 384 385 // Return status modes 386 Symbol* result() const { return _exception_type; } 387 bool has_error() const { return result() != NULL; } 388 char* exception_message() { 389 stringStream ss; 390 ss.print("%s", _message); 391 _error_context.details(&ss, _method()); 392 return ss.as_string(); 393 } 394 395 // Called when verify or class format errors are encountered. 396 // May throw an exception based upon the mode. 397 void verify_error(ErrorContext ctx, const char* fmt, ...) ATTRIBUTE_PRINTF(3, 4); 398 void class_format_error(const char* fmt, ...) ATTRIBUTE_PRINTF(2, 3); 399 400 Klass* load_class(Symbol* name, TRAPS); 401 402 int change_sig_to_verificationType( 403 SignatureStream* sig_type, VerificationType* inference_type, TRAPS); 404 405 VerificationType cp_index_to_type(int index, const constantPoolHandle& cp, TRAPS) { 406 return VerificationType::reference_type(cp->klass_name_at(index)); 407 } 408 409 // Keep a list of temporary symbols created during verification because 410 // their reference counts need to be decremented when the verifier object 411 // goes out of scope. Since these symbols escape the scope in which they're 412 // created, we can't use a TempNewSymbol. 413 Symbol* create_temporary_symbol(const Symbol* s, int begin, int end, TRAPS); 414 Symbol* create_temporary_symbol(const char *s, int length, TRAPS); 415 416 Symbol* create_temporary_symbol(Symbol* s) { 417 // This version just updates the reference count and saves the symbol to be 418 // dereferenced later. 419 s->increment_refcount(); 420 _symbols->push(s); 421 return s; 422 } 423 424 TypeOrigin ref_ctx(const char* str, TRAPS); 425 426 }; 427 428 inline int ClassVerifier::change_sig_to_verificationType( 429 SignatureStream* sig_type, VerificationType* inference_type, TRAPS) { 430 BasicType bt = sig_type->type(); 431 switch (bt) { 432 case T_OBJECT: 433 case T_ARRAY: 434 { 435 Symbol* name = sig_type->as_symbol(CHECK_0); 436 // Create another symbol to save as signature stream unreferences this symbol. 437 Symbol* name_copy = create_temporary_symbol(name); 438 assert(name_copy == name, "symbols don't match"); 439 *inference_type = 440 VerificationType::reference_type(name_copy); 441 return 1; 442 } 443 case T_LONG: 444 *inference_type = VerificationType::long_type(); 445 *++inference_type = VerificationType::long2_type(); 446 return 2; 447 case T_DOUBLE: 448 *inference_type = VerificationType::double_type(); 449 *++inference_type = VerificationType::double2_type(); 450 return 2; 451 case T_INT: 452 case T_BOOLEAN: 453 case T_BYTE: 454 case T_CHAR: 455 case T_SHORT: 456 *inference_type = VerificationType::integer_type(); 457 return 1; 458 case T_FLOAT: 459 *inference_type = VerificationType::float_type(); 460 return 1; 461 default: 462 ShouldNotReachHere(); 463 return 1; 464 } 465 } 466 467 #endif // SHARE_VM_CLASSFILE_VERIFIER_HPP