| 1 | // nacl.h -- Native Client support for gold -*- C++ -*- |
| 2 | |
| 3 | // Copyright (C) 2012-2020 Free Software Foundation, Inc. |
| 4 | |
| 5 | // This file is part of gold. |
| 6 | |
| 7 | // This program is free software; you can redistribute it and/or modify |
| 8 | // it under the terms of the GNU General Public License as published by |
| 9 | // the Free Software Foundation; either version 3 of the License, or |
| 10 | // (at your option) any later version. |
| 11 | |
| 12 | // This program is distributed in the hope that it will be useful, |
| 13 | // but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | // GNU General Public License for more details. |
| 16 | |
| 17 | // You should have received a copy of the GNU General Public License |
| 18 | // along with this program; if not, write to the Free Software |
| 19 | // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, |
| 20 | // MA 02110-1301, USA. |
| 21 | |
| 22 | #include "elfcpp_file.h" |
| 23 | #include "fileread.h" |
| 24 | #include "layout.h" |
| 25 | #include "target-select.h" |
| 26 | #include "target.h" |
| 27 | |
| 28 | #ifndef GOLD_NACL_H |
| 29 | #define GOLD_NACL_H |
| 30 | |
| 31 | namespace gold |
| 32 | { |
| 33 | |
| 34 | class Sniff_file |
| 35 | { |
| 36 | public: |
| 37 | Sniff_file(Input_file* input_file, off_t offset) |
| 38 | : file_(input_file->file()), offset_(offset) |
| 39 | { } |
| 40 | |
| 41 | class Location |
| 42 | { |
| 43 | public: |
| 44 | Location(off_t file_offset, off_t data_size) |
| 45 | : offset_(file_offset), size_(data_size) |
| 46 | { } |
| 47 | |
| 48 | inline off_t offset() const |
| 49 | { return this->offset_; } |
| 50 | |
| 51 | inline section_size_type size() const |
| 52 | { return this->size_; } |
| 53 | |
| 54 | private: |
| 55 | off_t offset_; |
| 56 | section_size_type size_; |
| 57 | }; |
| 58 | |
| 59 | class View |
| 60 | { |
| 61 | public: |
| 62 | View(File_read& file, off_t file_offset, off_t data_size) |
| 63 | : data_(file.get_view(file_offset, 0, data_size, true, false)) |
| 64 | { } |
| 65 | |
| 66 | const unsigned char* data() |
| 67 | { return this->data_; } |
| 68 | |
| 69 | private: |
| 70 | const unsigned char* data_; |
| 71 | }; |
| 72 | |
| 73 | View view(off_t file_offset, off_t data_size) |
| 74 | { |
| 75 | return View(this->file_, this->offset_ + file_offset, data_size); |
| 76 | } |
| 77 | |
| 78 | View view(Location loc) |
| 79 | { |
| 80 | return this->view(loc.offset(), loc.size()); |
| 81 | } |
| 82 | |
| 83 | // Report an error. |
| 84 | void |
| 85 | error(const char* format, ...) const ATTRIBUTE_PRINTF_2; |
| 86 | |
| 87 | private: |
| 88 | File_read& file_; |
| 89 | off_t offset_; |
| 90 | }; |
| 91 | |
| 92 | |
| 93 | template<class base_selector, class nacl_target> |
| 94 | class Target_selector_nacl : public base_selector |
| 95 | { |
| 96 | public: |
| 97 | Target_selector_nacl(const char* nacl_abi_name, |
| 98 | const char* bfd_name, const char* emulation) |
| 99 | : base_selector(), is_nacl_(false), nacl_abi_name_(nacl_abi_name), |
| 100 | bfd_name_(bfd_name), emulation_(emulation) |
| 101 | { } |
| 102 | |
| 103 | protected: |
| 104 | virtual Target* |
| 105 | do_instantiate_target() |
| 106 | { |
| 107 | if (this->is_nacl_) |
| 108 | return new nacl_target(); |
| 109 | return this->base_selector::do_instantiate_target(); |
| 110 | } |
| 111 | |
| 112 | virtual Target* |
| 113 | do_recognize(Input_file* file, off_t offset, |
| 114 | int machine, int osabi, int abiversion) |
| 115 | { |
| 116 | this->is_nacl_ = file != NULL && this->recognize_nacl_file(file, offset); |
| 117 | if (this->is_nacl_) |
| 118 | return this->instantiate_target(); |
| 119 | return this->base_selector::do_recognize(file, offset, |
| 120 | machine, osabi, abiversion); |
| 121 | } |
| 122 | |
| 123 | virtual Target* |
| 124 | do_recognize_by_bfd_name(const char* name) |
| 125 | { |
| 126 | gold_assert(this->bfd_name_ != NULL); |
| 127 | this->is_nacl_ = strcmp(name, this->bfd_name_) == 0; |
| 128 | if (this->is_nacl_) |
| 129 | return this->instantiate_target(); |
| 130 | return this->base_selector::do_recognize_by_bfd_name(name); |
| 131 | } |
| 132 | |
| 133 | virtual void |
| 134 | do_supported_bfd_names(std::vector<const char*>* names) |
| 135 | { |
| 136 | gold_assert(this->bfd_name_ != NULL); |
| 137 | this->base_selector::do_supported_bfd_names(names); |
| 138 | names->push_back(this->bfd_name_); |
| 139 | } |
| 140 | |
| 141 | virtual void |
| 142 | do_supported_emulations(std::vector<const char*>* emulations) |
| 143 | { |
| 144 | gold_assert(this->emulation_ != NULL); |
| 145 | this->base_selector::do_supported_emulations(emulations); |
| 146 | emulations->push_back(this->emulation_); |
| 147 | } |
| 148 | |
| 149 | virtual const char* |
| 150 | do_target_bfd_name(const Target* target) |
| 151 | { |
| 152 | return (!this->is_our_target(target) |
| 153 | ? NULL |
| 154 | : (this->is_nacl_ |
| 155 | ? this->bfd_name_ |
| 156 | : base_selector::do_target_bfd_name(target))); |
| 157 | } |
| 158 | |
| 159 | private: |
| 160 | bool |
| 161 | recognize_nacl_file(Input_file* input_file, off_t offset) |
| 162 | { |
| 163 | if (this->is_big_endian()) |
| 164 | { |
| 165 | #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG) |
| 166 | # ifdef HAVE_TARGET_32_BIG |
| 167 | if (this->get_size() == 32) |
| 168 | return do_recognize_nacl_file<32, true>(input_file, offset); |
| 169 | # endif |
| 170 | # ifdef HAVE_TARGET_64_BIG |
| 171 | if (this->get_size() == 64) |
| 172 | return do_recognize_nacl_file<64, true>(input_file, offset); |
| 173 | # endif |
| 174 | #endif |
| 175 | gold_unreachable(); |
| 176 | } |
| 177 | else |
| 178 | { |
| 179 | #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE) |
| 180 | # ifdef HAVE_TARGET_32_LITTLE |
| 181 | if (this->get_size() == 32) |
| 182 | return do_recognize_nacl_file<32, false>(input_file, offset); |
| 183 | # endif |
| 184 | # ifdef HAVE_TARGET_64_LITTLE |
| 185 | if (this->get_size() == 64) |
| 186 | return do_recognize_nacl_file<64, false>(input_file, offset); |
| 187 | # endif |
| 188 | #endif |
| 189 | gold_unreachable(); |
| 190 | } |
| 191 | } |
| 192 | |
| 193 | template<int size, bool big_endian> |
| 194 | bool |
| 195 | do_recognize_nacl_file(Input_file* input_file, off_t offset) |
| 196 | { |
| 197 | Sniff_file file(input_file, offset); |
| 198 | elfcpp::Elf_file<size, big_endian, Sniff_file> elf_file(&file); |
| 199 | const unsigned int shnum = elf_file.shnum(); |
| 200 | for (unsigned int shndx = 1; shndx < shnum; ++shndx) |
| 201 | { |
| 202 | if (elf_file.section_type(shndx) == elfcpp::SHT_NOTE) |
| 203 | { |
| 204 | Sniff_file::Location loc = elf_file.section_contents(shndx); |
| 205 | if (loc.size() < (3 * 4 |
| 206 | + align_address(sizeof "NaCl", 4) |
| 207 | + align_address(nacl_abi_name_.size() + 1, 4))) |
| 208 | continue; |
| 209 | Sniff_file::View view(file.view(loc)); |
| 210 | const unsigned char* note_data = view.data(); |
| 211 | if ((elfcpp::Swap<32, big_endian>::readval(note_data + 0) |
| 212 | == sizeof "NaCl") |
| 213 | && (elfcpp::Swap<32, big_endian>::readval(note_data + 4) |
| 214 | == nacl_abi_name_.size() + 1) |
| 215 | && (elfcpp::Swap<32, big_endian>::readval(note_data + 8) |
| 216 | == elfcpp::NT_VERSION)) |
| 217 | { |
| 218 | const unsigned char* name = note_data + 12; |
| 219 | const unsigned char* desc = (name |
| 220 | + align_address(sizeof "NaCl", 4)); |
| 221 | if (memcmp(name, "NaCl", sizeof "NaCl") == 0 |
| 222 | && memcmp(desc, nacl_abi_name_.c_str(), |
| 223 | nacl_abi_name_.size() + 1) == 0) |
| 224 | return true; |
| 225 | } |
| 226 | } |
| 227 | } |
| 228 | return false; |
| 229 | } |
| 230 | |
| 231 | // Whether we decided this was the NaCl target variant. |
| 232 | bool is_nacl_; |
| 233 | // The string found in the NaCl ABI note. |
| 234 | std::string nacl_abi_name_; |
| 235 | // BFD name of NaCl target, for compatibility. |
| 236 | const char* const bfd_name_; |
| 237 | // GNU linker emulation for this NaCl target, for compatibility. |
| 238 | const char* const emulation_; |
| 239 | }; |
| 240 | |
| 241 | } // end namespace gold |
| 242 | |
| 243 | #endif // !defined(GOLD_NACL_H) |