1/*
2 * Copyright (c) 1997, 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_UTILITIES_ELF_FILE_HPP
26#define SHARE_VM_UTILITIES_ELF_FILE_HPP
27
28#if !defined(_WINDOWS) && !defined(__APPLE__)
29
30#if defined(__OpenBSD__)
31#include <sys/exec_elf.h>
32#else
33#include <elf.h>
34#endif
35#include <stdio.h>
36
37#ifdef _LP64
38
39typedef Elf64_Half      Elf_Half;
40typedef Elf64_Word      Elf_Word;
41typedef Elf64_Off       Elf_Off;
42typedef Elf64_Addr      Elf_Addr;
43
44typedef Elf64_Ehdr      Elf_Ehdr;
45typedef Elf64_Shdr      Elf_Shdr;
46typedef Elf64_Phdr      Elf_Phdr;
47typedef Elf64_Sym       Elf_Sym;
48
49#if !defined(_ALLBSD_SOURCE) || defined(__APPLE__)
50#define ELF_ST_TYPE ELF64_ST_TYPE
51#endif
52
53#else
54
55typedef Elf32_Half      Elf_Half;
56typedef Elf32_Word      Elf_Word;
57typedef Elf32_Off       Elf_Off;
58typedef Elf32_Addr      Elf_Addr;
59
60
61typedef Elf32_Ehdr      Elf_Ehdr;
62typedef Elf32_Shdr      Elf_Shdr;
63typedef Elf32_Phdr      Elf_Phdr;
64typedef Elf32_Sym       Elf_Sym;
65
66#if !defined(_ALLBSD_SOURCE) || defined(__APPLE__)
67#define ELF_ST_TYPE ELF32_ST_TYPE
68#endif
69#endif
70
71#include "globalDefinitions.hpp"
72#include "memory/allocation.hpp"
73#include "utilities/decoder.hpp"
74
75
76class ElfStringTable;
77class ElfSymbolTable;
78class ElfFuncDescTable;
79
80
81// On Solaris/Linux platforms, libjvm.so does contain all private symbols.
82// ElfFile is basically an elf file parser, which can lookup the symbol
83// that is the nearest to the given address.
84// Beware, this code is called from vm error reporting code, when vm is already
85// in "error" state, so there are scenarios, lookup will fail. We want this
86// part of code to be very defensive, and bait out if anything went wrong.
87
88class ElfFile: public CHeapObj<mtInternal> {
89  friend class ElfDecoder;
90 public:
91  ElfFile(const char* filepath);
92  ~ElfFile();
93
94  bool decode(address addr, char* buf, int buflen, int* offset);
95  const char* filepath() {
96    return m_filepath;
97  }
98
99  bool same_elf_file(const char* filepath) {
100    assert(filepath, "null file path");
101    assert(m_filepath, "already out of memory");
102    return (m_filepath && !strcmp(filepath, m_filepath));
103  }
104
105  NullDecoder::decoder_status get_status() {
106    return m_status;
107  }
108
109 private:
110  // sanity check, if the file is a real elf file
111  static bool is_elf_file(Elf_Ehdr&);
112
113  // load string tables from the elf file
114  bool load_tables();
115
116  // string tables are stored in a linked list
117  void add_string_table(ElfStringTable* table);
118
119  // symbol tables are stored in a linked list
120  void add_symbol_table(ElfSymbolTable* table);
121
122  // return a string table at specified section index
123  ElfStringTable* get_string_table(int index);
124
125protected:
126   ElfFile*  next() const { return m_next; }
127   void set_next(ElfFile* file) { m_next = file; }
128
129 public:
130  // Returns true if the elf file is marked NOT to require an executable stack,
131  // or if the file could not be opened.
132  // Returns false if the elf file requires an executable stack, the stack flag
133  // is not set at all, or if the file can not be read.
134  // On systems other than linux it always returns false.
135  static bool specifies_noexecstack(const char* filepath) NOT_LINUX({ return false; });
136
137 protected:
138    ElfFile*         m_next;
139
140 private:
141  // file
142  const char* m_filepath;
143  FILE* m_file;
144
145  // Elf header
146  Elf_Ehdr                     m_elfHdr;
147
148  // symbol tables
149  ElfSymbolTable*              m_symbol_tables;
150
151  // string tables
152  ElfStringTable*              m_string_tables;
153
154  // function descriptors table
155  ElfFuncDescTable*            m_funcDesc_table;
156
157  NullDecoder::decoder_status  m_status;
158};
159
160#endif // !_WINDOWS && !__APPLE__
161
162#endif // SHARE_VM_UTILITIES_ELF_FILE_HPP
163