src/hotspot/share/classfile/verifier.hpp
changeset 47216 71c04702a3d5
parent 46329 53ccc37bda19
child 48826 c4d9d1b08e2e
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/classfile/verifier.hpp	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,472 @@
+/*
+ * Copyright (c) 1998, 2017, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#ifndef SHARE_VM_CLASSFILE_VERIFIER_HPP
+#define SHARE_VM_CLASSFILE_VERIFIER_HPP
+
+#include "classfile/verificationType.hpp"
+#include "gc/shared/gcLocker.hpp"
+#include "oops/klass.hpp"
+#include "oops/method.hpp"
+#include "runtime/handles.hpp"
+#include "utilities/exceptions.hpp"
+#include "utilities/growableArray.hpp"
+
+// The verifier class
+class Verifier : AllStatic {
+ public:
+  enum {
+    STRICTER_ACCESS_CTRL_CHECK_VERSION  = 49,
+    STACKMAP_ATTRIBUTE_MAJOR_VERSION    = 50,
+    INVOKEDYNAMIC_MAJOR_VERSION         = 51,
+    NO_RELAX_ACCESS_CTRL_CHECK_VERSION  = 52
+  };
+  typedef enum { ThrowException, NoException } Mode;
+
+  /**
+   * Verify the bytecodes for a class.  If 'throw_exception' is true
+   * then the appropriate VerifyError or ClassFormatError will be thrown.
+   * Otherwise, no exception is thrown and the return indicates the
+   * error.
+   */
+  static void log_end_verification(outputStream* st, const char* klassName, Symbol* exception_name, TRAPS);
+  static bool verify(InstanceKlass* klass, Mode mode, bool should_verify_class, TRAPS);
+
+  // Return false if the class is loaded by the bootstrap loader,
+  // or if defineClass was called requesting skipping verification
+  // -Xverify:all/none override this value
+  static bool should_verify_for(oop class_loader, bool should_verify_class);
+
+  // Relax certain access checks to enable some broken 1.1 apps to run on 1.2.
+  static bool relax_access_for(oop class_loader);
+
+  // Print output for class+resolve
+  static void trace_class_resolution(Klass* resolve_class, InstanceKlass* verify_class);
+
+ private:
+  static bool is_eligible_for_verification(InstanceKlass* klass, bool should_verify_class);
+  static Symbol* inference_verify(
+    InstanceKlass* klass, char* msg, size_t msg_len, TRAPS);
+};
+
+class RawBytecodeStream;
+class StackMapFrame;
+class StackMapTable;
+
+// Summary of verifier's memory usage:
+// StackMapTable is stack allocated.
+// StackMapFrame are resource allocated. There is only one ResourceMark
+// for each class verification, which is created at the top level.
+// There is one mutable StackMapFrame (current_frame) which is updated
+// by abstract bytecode interpretation. frame_in_exception_handler() returns
+// a frame that has a mutable one-item stack (ready for pushing the
+// catch type exception object). All the other StackMapFrame's
+// are immutable (including their locals and stack arrays) after
+// their constructions.
+// locals/stack arrays in StackMapFrame are resource allocated.
+// locals/stack arrays can be shared between StackMapFrame's, except
+// the mutable StackMapFrame (current_frame).
+
+// These macros are used similarly to CHECK macros but also check
+// the status of the verifier and return if that has an error.
+#define CHECK_VERIFY(verifier) \
+  CHECK); if ((verifier)->has_error()) return; ((void)0
+#define CHECK_VERIFY_(verifier, result) \
+  CHECK_(result)); if ((verifier)->has_error()) return (result); ((void)0
+
+class TypeOrigin VALUE_OBJ_CLASS_SPEC {
+ private:
+  typedef enum {
+    CF_LOCALS,  // Comes from the current frame locals
+    CF_STACK,   // Comes from the current frame expression stack
+    SM_LOCALS,  // Comes from stackmap locals
+    SM_STACK,   // Comes from stackmap expression stack
+    CONST_POOL, // Comes from the constant pool
+    SIG,        // Comes from method signature
+    IMPLICIT,   // Comes implicitly from code or context
+    BAD_INDEX,  // No type, but the index is bad
+    FRAME_ONLY, // No type, context just contains the frame
+    NONE
+  } Origin;
+
+  Origin _origin;
+  u2 _index;              // local, stack, or constant pool index
+  StackMapFrame* _frame;  // source frame if CF or SM
+  VerificationType _type; // The actual type
+
+  TypeOrigin(
+      Origin origin, u2 index, StackMapFrame* frame, VerificationType type)
+      : _origin(origin), _index(index), _frame(frame), _type(type) {}
+
+ public:
+  TypeOrigin() : _origin(NONE), _index(0), _frame(NULL) {}
+
+  static TypeOrigin null();
+  static TypeOrigin local(u2 index, StackMapFrame* frame);
+  static TypeOrigin stack(u2 index, StackMapFrame* frame);
+  static TypeOrigin sm_local(u2 index, StackMapFrame* frame);
+  static TypeOrigin sm_stack(u2 index, StackMapFrame* frame);
+  static TypeOrigin cp(u2 index, VerificationType vt);
+  static TypeOrigin signature(VerificationType vt);
+  static TypeOrigin bad_index(u2 index);
+  static TypeOrigin implicit(VerificationType t);
+  static TypeOrigin frame(StackMapFrame* frame);
+
+  void reset_frame();
+  void details(outputStream* ss) const;
+  void print_frame(outputStream* ss) const;
+  const StackMapFrame* frame() const { return _frame; }
+  bool is_valid() const { return _origin != NONE; }
+  u2 index() const { return _index; }
+
+#ifdef ASSERT
+  void print_on(outputStream* str) const;
+#endif
+};
+
+class ErrorContext VALUE_OBJ_CLASS_SPEC {
+ private:
+  typedef enum {
+    INVALID_BYTECODE,     // There was a problem with the bytecode
+    WRONG_TYPE,           // Type value was not as expected
+    FLAGS_MISMATCH,       // Frame flags are not assignable
+    BAD_CP_INDEX,         // Invalid constant pool index
+    BAD_LOCAL_INDEX,      // Invalid local index
+    LOCALS_SIZE_MISMATCH, // Frames have differing local counts
+    STACK_SIZE_MISMATCH,  // Frames have different stack sizes
+    STACK_OVERFLOW,       // Attempt to push onto a full expression stack
+    STACK_UNDERFLOW,      // Attempt to pop and empty expression stack
+    MISSING_STACKMAP,     // No stackmap for this location and there should be
+    BAD_STACKMAP,         // Format error in stackmap
+    NO_FAULT,             // No error
+    UNKNOWN
+  } FaultType;
+
+  int _bci;
+  FaultType _fault;
+  TypeOrigin _type;
+  TypeOrigin _expected;
+
+  ErrorContext(int bci, FaultType fault) :
+      _bci(bci), _fault(fault)  {}
+  ErrorContext(int bci, FaultType fault, TypeOrigin type) :
+      _bci(bci), _fault(fault), _type(type)  {}
+  ErrorContext(int bci, FaultType fault, TypeOrigin type, TypeOrigin exp) :
+      _bci(bci), _fault(fault), _type(type), _expected(exp)  {}
+
+ public:
+  ErrorContext() : _bci(-1), _fault(NO_FAULT) {}
+
+  static ErrorContext bad_code(u2 bci) {
+    return ErrorContext(bci, INVALID_BYTECODE);
+  }
+  static ErrorContext bad_type(u2 bci, TypeOrigin type) {
+    return ErrorContext(bci, WRONG_TYPE, type);
+  }
+  static ErrorContext bad_type(u2 bci, TypeOrigin type, TypeOrigin exp) {
+    return ErrorContext(bci, WRONG_TYPE, type, exp);
+  }
+  static ErrorContext bad_flags(u2 bci, StackMapFrame* frame) {
+    return ErrorContext(bci, FLAGS_MISMATCH, TypeOrigin::frame(frame));
+  }
+  static ErrorContext bad_flags(u2 bci, StackMapFrame* cur, StackMapFrame* sm) {
+    return ErrorContext(bci, FLAGS_MISMATCH,
+                        TypeOrigin::frame(cur), TypeOrigin::frame(sm));
+  }
+  static ErrorContext bad_cp_index(u2 bci, u2 index) {
+    return ErrorContext(bci, BAD_CP_INDEX, TypeOrigin::bad_index(index));
+  }
+  static ErrorContext bad_local_index(u2 bci, u2 index) {
+    return ErrorContext(bci, BAD_LOCAL_INDEX, TypeOrigin::bad_index(index));
+  }
+  static ErrorContext locals_size_mismatch(
+      u2 bci, StackMapFrame* frame0, StackMapFrame* frame1) {
+    return ErrorContext(bci, LOCALS_SIZE_MISMATCH,
+        TypeOrigin::frame(frame0), TypeOrigin::frame(frame1));
+  }
+  static ErrorContext stack_size_mismatch(
+      u2 bci, StackMapFrame* frame0, StackMapFrame* frame1) {
+    return ErrorContext(bci, STACK_SIZE_MISMATCH,
+        TypeOrigin::frame(frame0), TypeOrigin::frame(frame1));
+  }
+  static ErrorContext stack_overflow(u2 bci, StackMapFrame* frame) {
+    return ErrorContext(bci, STACK_OVERFLOW, TypeOrigin::frame(frame));
+  }
+  static ErrorContext stack_underflow(u2 bci, StackMapFrame* frame) {
+    return ErrorContext(bci, STACK_UNDERFLOW, TypeOrigin::frame(frame));
+  }
+  static ErrorContext missing_stackmap(u2 bci) {
+    return ErrorContext(bci, MISSING_STACKMAP);
+  }
+  static ErrorContext bad_stackmap(int index, StackMapFrame* frame) {
+    return ErrorContext(0, BAD_STACKMAP, TypeOrigin::frame(frame));
+  }
+
+  bool is_valid() const { return _fault != NO_FAULT; }
+  int bci() const { return _bci; }
+
+  void reset_frames() {
+    _type.reset_frame();
+    _expected.reset_frame();
+  }
+
+  void details(outputStream* ss, const Method* method) const;
+
+#ifdef ASSERT
+  void print_on(outputStream* str) const {
+    str->print("error_context(%d, %d,", _bci, _fault);
+    _type.print_on(str);
+    str->print(",");
+    _expected.print_on(str);
+    str->print(")");
+  }
+#endif
+
+ private:
+  void location_details(outputStream* ss, const Method* method) const;
+  void reason_details(outputStream* ss) const;
+  void frame_details(outputStream* ss) const;
+  void bytecode_details(outputStream* ss, const Method* method) const;
+  void handler_details(outputStream* ss, const Method* method) const;
+  void stackmap_details(outputStream* ss, const Method* method) const;
+};
+
+// A new instance of this class is created for each class being verified
+class ClassVerifier : public StackObj {
+ private:
+  Thread* _thread;
+  GrowableArray<Symbol*>* _symbols;  // keep a list of symbols created
+
+  Symbol* _exception_type;
+  char* _message;
+
+  ErrorContext _error_context;  // contains information about an error
+
+  void verify_method(const methodHandle& method, TRAPS);
+  char* generate_code_data(const methodHandle& m, u4 code_length, TRAPS);
+  void verify_exception_handler_table(u4 code_length, char* code_data,
+                                      int& min, int& max, TRAPS);
+  void verify_local_variable_table(u4 code_length, char* code_data, TRAPS);
+
+  VerificationType cp_ref_index_to_type(
+      int index, const constantPoolHandle& cp, TRAPS) {
+    return cp_index_to_type(cp->klass_ref_index_at(index), cp, THREAD);
+  }
+
+  bool is_protected_access(
+    InstanceKlass* this_class, Klass* target_class,
+    Symbol* field_name, Symbol* field_sig, bool is_method);
+
+  void verify_cp_index(u2 bci, const constantPoolHandle& cp, int index, TRAPS);
+  void verify_cp_type(u2 bci, int index, const constantPoolHandle& cp,
+      unsigned int types, TRAPS);
+  void verify_cp_class_type(u2 bci, int index, const constantPoolHandle& cp, TRAPS);
+
+  u2 verify_stackmap_table(
+    u2 stackmap_index, u2 bci, StackMapFrame* current_frame,
+    StackMapTable* stackmap_table, bool no_control_flow, TRAPS);
+
+  void verify_exception_handler_targets(
+    u2 bci, bool this_uninit, StackMapFrame* current_frame,
+    StackMapTable* stackmap_table, TRAPS);
+
+  void verify_ldc(
+    int opcode, u2 index, StackMapFrame *current_frame,
+    const constantPoolHandle& cp, u2 bci, TRAPS);
+
+  void verify_switch(
+    RawBytecodeStream* bcs, u4 code_length, char* code_data,
+    StackMapFrame* current_frame, StackMapTable* stackmap_table, TRAPS);
+
+  void verify_field_instructions(
+    RawBytecodeStream* bcs, StackMapFrame* current_frame,
+    const constantPoolHandle& cp, bool allow_arrays, TRAPS);
+
+  void verify_invoke_init(
+    RawBytecodeStream* bcs, u2 ref_index, VerificationType ref_class_type,
+    StackMapFrame* current_frame, u4 code_length, bool in_try_block,
+    bool* this_uninit, const constantPoolHandle& cp, StackMapTable* stackmap_table,
+    TRAPS);
+
+  // Used by ends_in_athrow() to push all handlers that contain bci onto the
+  // handler_stack, if the handler has not already been pushed on the stack.
+  void push_handlers(ExceptionTable* exhandlers,
+                     GrowableArray<u4>* handler_list,
+                     GrowableArray<u4>* handler_stack,
+                     u4 bci);
+
+  // Returns true if all paths starting with start_bc_offset end in athrow
+  // bytecode or loop.
+  bool ends_in_athrow(u4 start_bc_offset);
+
+  void verify_invoke_instructions(
+    RawBytecodeStream* bcs, u4 code_length, StackMapFrame* current_frame,
+    bool in_try_block, bool* this_uninit, VerificationType return_type,
+    const constantPoolHandle& cp, StackMapTable* stackmap_table, TRAPS);
+
+  VerificationType get_newarray_type(u2 index, u2 bci, TRAPS);
+  void verify_anewarray(u2 bci, u2 index, const constantPoolHandle& cp,
+      StackMapFrame* current_frame, TRAPS);
+  void verify_return_value(
+      VerificationType return_type, VerificationType type, u2 offset,
+      StackMapFrame* current_frame, TRAPS);
+
+  void verify_iload (u2 index, StackMapFrame* current_frame, TRAPS);
+  void verify_lload (u2 index, StackMapFrame* current_frame, TRAPS);
+  void verify_fload (u2 index, StackMapFrame* current_frame, TRAPS);
+  void verify_dload (u2 index, StackMapFrame* current_frame, TRAPS);
+  void verify_aload (u2 index, StackMapFrame* current_frame, TRAPS);
+  void verify_istore(u2 index, StackMapFrame* current_frame, TRAPS);
+  void verify_lstore(u2 index, StackMapFrame* current_frame, TRAPS);
+  void verify_fstore(u2 index, StackMapFrame* current_frame, TRAPS);
+  void verify_dstore(u2 index, StackMapFrame* current_frame, TRAPS);
+  void verify_astore(u2 index, StackMapFrame* current_frame, TRAPS);
+  void verify_iinc  (u2 index, StackMapFrame* current_frame, TRAPS);
+
+  bool name_in_supers(Symbol* ref_name, InstanceKlass* current);
+
+  VerificationType object_type() const;
+
+  InstanceKlass*      _klass;  // the class being verified
+  methodHandle        _method; // current method being verified
+  VerificationType    _this_type; // the verification type of the current class
+
+  // Some recursive calls from the verifier to the name resolver
+  // can cause the current class to be re-verified and rewritten.
+  // If this happens, the original verification should not continue,
+  // because constant pool indexes will have changed.
+  // The rewriter is preceded by the verifier.  If the verifier throws
+  // an error, rewriting is prevented.  Also, rewriting always precedes
+  // bytecode execution or compilation.  Thus, is_rewritten implies
+  // that a class has been verified and prepared for execution.
+  bool was_recursively_verified() { return _klass->is_rewritten(); }
+
+  bool is_same_or_direct_interface(InstanceKlass* klass,
+    VerificationType klass_type, VerificationType ref_class_type);
+
+ public:
+  enum {
+    BYTECODE_OFFSET = 1,
+    NEW_OFFSET = 2
+  };
+
+  // constructor
+  ClassVerifier(InstanceKlass* klass, TRAPS);
+
+  // destructor
+  ~ClassVerifier();
+
+  Thread* thread()             { return _thread; }
+  const methodHandle& method() { return _method; }
+  InstanceKlass* current_class() const { return _klass; }
+  VerificationType current_type() const { return _this_type; }
+
+  // Verifies the class.  If a verify or class file format error occurs,
+  // the '_exception_name' symbols will set to the exception name and
+  // the message_buffer will be filled in with the exception message.
+  void verify_class(TRAPS);
+
+  // Return status modes
+  Symbol* result() const { return _exception_type; }
+  bool has_error() const { return result() != NULL; }
+  char* exception_message() {
+    stringStream ss;
+    ss.print("%s", _message);
+    _error_context.details(&ss, _method());
+    return ss.as_string();
+  }
+
+  // Called when verify or class format errors are encountered.
+  // May throw an exception based upon the mode.
+  void verify_error(ErrorContext ctx, const char* fmt, ...) ATTRIBUTE_PRINTF(3, 4);
+  void class_format_error(const char* fmt, ...) ATTRIBUTE_PRINTF(2, 3);
+
+  Klass* load_class(Symbol* name, TRAPS);
+
+  int change_sig_to_verificationType(
+    SignatureStream* sig_type, VerificationType* inference_type, TRAPS);
+
+  VerificationType cp_index_to_type(int index, const constantPoolHandle& cp, TRAPS) {
+    return VerificationType::reference_type(cp->klass_name_at(index));
+  }
+
+  // Keep a list of temporary symbols created during verification because
+  // their reference counts need to be decremented when the verifier object
+  // goes out of scope.  Since these symbols escape the scope in which they're
+  // created, we can't use a TempNewSymbol.
+  Symbol* create_temporary_symbol(const Symbol* s, int begin, int end, TRAPS);
+  Symbol* create_temporary_symbol(const char *s, int length, TRAPS);
+
+  Symbol* create_temporary_symbol(Symbol* s) {
+    // This version just updates the reference count and saves the symbol to be
+    // dereferenced later.
+    s->increment_refcount();
+    _symbols->push(s);
+    return s;
+  }
+
+  TypeOrigin ref_ctx(const char* str, TRAPS);
+
+};
+
+inline int ClassVerifier::change_sig_to_verificationType(
+    SignatureStream* sig_type, VerificationType* inference_type, TRAPS) {
+  BasicType bt = sig_type->type();
+  switch (bt) {
+    case T_OBJECT:
+    case T_ARRAY:
+      {
+        Symbol* name = sig_type->as_symbol(CHECK_0);
+        // Create another symbol to save as signature stream unreferences this symbol.
+        Symbol* name_copy = create_temporary_symbol(name);
+        assert(name_copy == name, "symbols don't match");
+        *inference_type =
+          VerificationType::reference_type(name_copy);
+        return 1;
+      }
+    case T_LONG:
+      *inference_type = VerificationType::long_type();
+      *++inference_type = VerificationType::long2_type();
+      return 2;
+    case T_DOUBLE:
+      *inference_type = VerificationType::double_type();
+      *++inference_type = VerificationType::double2_type();
+      return 2;
+    case T_INT:
+    case T_BOOLEAN:
+    case T_BYTE:
+    case T_CHAR:
+    case T_SHORT:
+      *inference_type = VerificationType::integer_type();
+      return 1;
+    case T_FLOAT:
+      *inference_type = VerificationType::float_type();
+      return 1;
+    default:
+      ShouldNotReachHere();
+      return 1;
+  }
+}
+
+#endif // SHARE_VM_CLASSFILE_VERIFIER_HPP