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 39 typedef Elf64_Half Elf_Half; 40 typedef Elf64_Word Elf_Word; 41 typedef Elf64_Off Elf_Off; 42 typedef Elf64_Addr Elf_Addr; 43 44 typedef Elf64_Ehdr Elf_Ehdr; 45 typedef Elf64_Shdr Elf_Shdr; 46 typedef Elf64_Phdr Elf_Phdr; 47 typedef 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 55 typedef Elf32_Half Elf_Half; 56 typedef Elf32_Word Elf_Word; 57 typedef Elf32_Off Elf_Off; 58 typedef Elf32_Addr Elf_Addr; 59 60 61 typedef Elf32_Ehdr Elf_Ehdr; 62 typedef Elf32_Shdr Elf_Shdr; 63 typedef Elf32_Phdr Elf_Phdr; 64 typedef 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 76 class ElfStringTable; 77 class ElfSymbolTable; 78 class 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 88 class ElfFile: public CHeapObj<mtInternal> { 89 friend class ElfDecoder; 90 public: 91 ElfFile(const char* filepath, bool load_tables); 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 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); 124 125 protected: 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 bool specifies_noexecstack() 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