1 /* ELF support for BFD. 2 Copyright (C) 1991-2020 Free Software Foundation, Inc. 3 4 Written by Fred Fish @ Cygnus Support, from information published 5 in "UNIX System V Release 4, Programmers Guide: ANSI C and 6 Programming Support Tools". 7 8 This file is part of BFD, the Binary File Descriptor library. 9 10 This program is free software; you can redistribute it and/or modify 11 it under the terms of the GNU General Public License as published by 12 the Free Software Foundation; either version 3 of the License, or 13 (at your option) any later version. 14 15 This program is distributed in the hope that it will be useful, 16 but WITHOUT ANY WARRANTY; without even the implied warranty of 17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 18 GNU General Public License for more details. 19 20 You should have received a copy of the GNU General Public License 21 along with this program; if not, write to the Free Software 22 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, 23 MA 02110-1301, USA. */ 24 25 /* This file is part of ELF support for BFD, and contains the portions 26 that describe how ELF is represented externally by the BFD library. 27 I.E. it describes the in-file representation of ELF. It requires 28 the elf/common.h file which contains the portions that are common to 29 both the internal and external representations. */ 30 31 /* The 64-bit stuff is kind of random. Perhaps someone will publish a 32 spec someday. */ 33 34 #ifndef _ELF_EXTERNAL_H 35 #define _ELF_EXTERNAL_H 36 37 /* Special section indices, which may show up in st_shndx fields, among 38 other places. */ 39 40 #define SHN_LORESERVE 0xFF00 /* Begin range of reserved indices */ 41 #define SHN_LOPROC 0xFF00 /* Begin range of appl-specific */ 42 #define SHN_HIPROC 0xFF1F /* End range of appl-specific */ 43 #define SHN_LOOS 0xFF20 /* OS specific semantics, lo */ 44 #define SHN_HIOS 0xFF3F /* OS specific semantics, hi */ 45 #define SHN_ABS 0xFFF1 /* Associated symbol is absolute */ 46 #define SHN_COMMON 0xFFF2 /* Associated symbol is in common */ 47 #define SHN_XINDEX 0xFFFF /* Section index is held elsewhere */ 48 #define SHN_HIRESERVE 0xFFFF /* End range of reserved indices */ 49 50 /* ELF Header (32-bit implementations) */ 51 52 typedef struct { 53 unsigned char e_ident[16]; /* ELF "magic number" */ 54 unsigned char e_type[2]; /* Identifies object file type */ 55 unsigned char e_machine[2]; /* Specifies required architecture */ 56 unsigned char e_version[4]; /* Identifies object file version */ 57 unsigned char e_entry[4]; /* Entry point virtual address */ 58 unsigned char e_phoff[4]; /* Program header table file offset */ 59 unsigned char e_shoff[4]; /* Section header table file offset */ 60 unsigned char e_flags[4]; /* Processor-specific flags */ 61 unsigned char e_ehsize[2]; /* ELF header size in bytes */ 62 unsigned char e_phentsize[2]; /* Program header table entry size */ 63 unsigned char e_phnum[2]; /* Program header table entry count */ 64 unsigned char e_shentsize[2]; /* Section header table entry size */ 65 unsigned char e_shnum[2]; /* Section header table entry count */ 66 unsigned char e_shstrndx[2]; /* Section header string table index */ 67 } Elf32_External_Ehdr; 68 69 typedef struct { 70 unsigned char e_ident[16]; /* ELF "magic number" */ 71 unsigned char e_type[2]; /* Identifies object file type */ 72 unsigned char e_machine[2]; /* Specifies required architecture */ 73 unsigned char e_version[4]; /* Identifies object file version */ 74 unsigned char e_entry[8]; /* Entry point virtual address */ 75 unsigned char e_phoff[8]; /* Program header table file offset */ 76 unsigned char e_shoff[8]; /* Section header table file offset */ 77 unsigned char e_flags[4]; /* Processor-specific flags */ 78 unsigned char e_ehsize[2]; /* ELF header size in bytes */ 79 unsigned char e_phentsize[2]; /* Program header table entry size */ 80 unsigned char e_phnum[2]; /* Program header table entry count */ 81 unsigned char e_shentsize[2]; /* Section header table entry size */ 82 unsigned char e_shnum[2]; /* Section header table entry count */ 83 unsigned char e_shstrndx[2]; /* Section header string table index */ 84 } Elf64_External_Ehdr; 85 86 /* Program header */ 87 88 typedef struct { 89 unsigned char p_type[4]; /* Identifies program segment type */ 90 unsigned char p_offset[4]; /* Segment file offset */ 91 unsigned char p_vaddr[4]; /* Segment virtual address */ 92 unsigned char p_paddr[4]; /* Segment physical address */ 93 unsigned char p_filesz[4]; /* Segment size in file */ 94 unsigned char p_memsz[4]; /* Segment size in memory */ 95 unsigned char p_flags[4]; /* Segment flags */ 96 unsigned char p_align[4]; /* Segment alignment, file & memory */ 97 } Elf32_External_Phdr; 98 99 typedef struct { 100 unsigned char p_type[4]; /* Identifies program segment type */ 101 unsigned char p_flags[4]; /* Segment flags */ 102 unsigned char p_offset[8]; /* Segment file offset */ 103 unsigned char p_vaddr[8]; /* Segment virtual address */ 104 unsigned char p_paddr[8]; /* Segment physical address */ 105 unsigned char p_filesz[8]; /* Segment size in file */ 106 unsigned char p_memsz[8]; /* Segment size in memory */ 107 unsigned char p_align[8]; /* Segment alignment, file & memory */ 108 } Elf64_External_Phdr; 109 110 /* Section header */ 111 112 typedef struct { 113 unsigned char sh_name[4]; /* Section name, index in string tbl */ 114 unsigned char sh_type[4]; /* Type of section */ 115 unsigned char sh_flags[4]; /* Miscellaneous section attributes */ 116 unsigned char sh_addr[4]; /* Section virtual addr at execution */ 117 unsigned char sh_offset[4]; /* Section file offset */ 118 unsigned char sh_size[4]; /* Size of section in bytes */ 119 unsigned char sh_link[4]; /* Index of another section */ 120 unsigned char sh_info[4]; /* Additional section information */ 121 unsigned char sh_addralign[4]; /* Section alignment */ 122 unsigned char sh_entsize[4]; /* Entry size if section holds table */ 123 } Elf32_External_Shdr; 124 125 typedef struct { 126 unsigned char sh_name[4]; /* Section name, index in string tbl */ 127 unsigned char sh_type[4]; /* Type of section */ 128 unsigned char sh_flags[8]; /* Miscellaneous section attributes */ 129 unsigned char sh_addr[8]; /* Section virtual addr at execution */ 130 unsigned char sh_offset[8]; /* Section file offset */ 131 unsigned char sh_size[8]; /* Size of section in bytes */ 132 unsigned char sh_link[4]; /* Index of another section */ 133 unsigned char sh_info[4]; /* Additional section information */ 134 unsigned char sh_addralign[8]; /* Section alignment */ 135 unsigned char sh_entsize[8]; /* Entry size if section holds table */ 136 } Elf64_External_Shdr; 137 138 /* Compression header */ 139 140 typedef struct { 141 unsigned char ch_type[4]; /* Type of compression */ 142 unsigned char ch_size[4]; /* Size of uncompressed data in bytes */ 143 unsigned char ch_addralign[4]; /* Alignment of uncompressed data */ 144 } Elf32_External_Chdr; 145 146 typedef struct { 147 unsigned char ch_type[4]; /* Type of compression */ 148 unsigned char ch_reserved[4]; /* Padding */ 149 unsigned char ch_size[8]; /* Size of uncompressed data in bytes */ 150 unsigned char ch_addralign[8]; /* Alignment of uncompressed data */ 151 } Elf64_External_Chdr; 152 153 /* Symbol table entry */ 154 155 typedef struct { 156 unsigned char st_name[4]; /* Symbol name, index in string tbl */ 157 unsigned char st_value[4]; /* Value of the symbol */ 158 unsigned char st_size[4]; /* Associated symbol size */ 159 unsigned char st_info[1]; /* Type and binding attributes */ 160 unsigned char st_other[1]; /* No defined meaning, 0 */ 161 unsigned char st_shndx[2]; /* Associated section index */ 162 } Elf32_External_Sym; 163 164 typedef struct { 165 unsigned char st_name[4]; /* Symbol name, index in string tbl */ 166 unsigned char st_info[1]; /* Type and binding attributes */ 167 unsigned char st_other[1]; /* No defined meaning, 0 */ 168 unsigned char st_shndx[2]; /* Associated section index */ 169 unsigned char st_value[8]; /* Value of the symbol */ 170 unsigned char st_size[8]; /* Associated symbol size */ 171 } Elf64_External_Sym; 172 173 typedef struct { 174 unsigned char est_shndx[4]; /* Section index */ 175 } Elf_External_Sym_Shndx; 176 177 /* Note segments */ 178 179 typedef struct { 180 unsigned char namesz[4]; /* Size of entry's owner string */ 181 unsigned char descsz[4]; /* Size of the note descriptor */ 182 unsigned char type[4]; /* Interpretation of the descriptor */ 183 char name[1]; /* Start of the name+desc data */ 184 } Elf_External_Note; 185 186 /* Align an address upward to a boundary, expressed as a number of bytes. 187 E.g. align to an 8-byte boundary with argument of 8. */ 188 #define ELF_ALIGN_UP(addr, boundary) \ 189 (((bfd_vma) (addr) + ((boundary) - 1)) & ~ (bfd_vma) ((boundary) -1)) 190 191 /* Compute the offset of the note descriptor from size of note entry's 192 owner string and note alignment. */ 193 #define ELF_NOTE_DESC_OFFSET(namesz, align) \ 194 ELF_ALIGN_UP (offsetof (Elf_External_Note, name) + (namesz), (align)) 195 196 /* Compute the offset of the next note entry from size of note entry's 197 owner string, size of the note descriptor and note alignment. */ 198 #define ELF_NOTE_NEXT_OFFSET(namesz, descsz, align) \ 199 ELF_ALIGN_UP (ELF_NOTE_DESC_OFFSET ((namesz), (align)) + (descsz), \ 200 (align)) 201 202 /* Relocation Entries */ 203 typedef struct { 204 unsigned char r_offset[4]; /* Location at which to apply the action */ 205 unsigned char r_info[4]; /* index and type of relocation */ 206 } Elf32_External_Rel; 207 208 typedef struct { 209 unsigned char r_offset[4]; /* Location at which to apply the action */ 210 unsigned char r_info[4]; /* index and type of relocation */ 211 unsigned char r_addend[4]; /* Constant addend used to compute value */ 212 } Elf32_External_Rela; 213 214 typedef struct { 215 unsigned char r_offset[8]; /* Location at which to apply the action */ 216 unsigned char r_info[8]; /* index and type of relocation */ 217 } Elf64_External_Rel; 218 219 typedef struct { 220 unsigned char r_offset[8]; /* Location at which to apply the action */ 221 unsigned char r_info[8]; /* index and type of relocation */ 222 unsigned char r_addend[8]; /* Constant addend used to compute value */ 223 } Elf64_External_Rela; 224 225 /* dynamic section structure */ 226 227 typedef struct { 228 unsigned char d_tag[4]; /* entry tag value */ 229 union { 230 unsigned char d_val[4]; 231 unsigned char d_ptr[4]; 232 } d_un; 233 } Elf32_External_Dyn; 234 235 typedef struct { 236 unsigned char d_tag[8]; /* entry tag value */ 237 union { 238 unsigned char d_val[8]; 239 unsigned char d_ptr[8]; 240 } d_un; 241 } Elf64_External_Dyn; 242 243 /* The version structures are currently size independent. They are 244 named without a 32 or 64. If that ever changes, these structures 245 will need to be renamed. */ 246 247 /* This structure appears in a SHT_GNU_verdef section. */ 248 249 typedef struct { 250 unsigned char vd_version[2]; 251 unsigned char vd_flags[2]; 252 unsigned char vd_ndx[2]; 253 unsigned char vd_cnt[2]; 254 unsigned char vd_hash[4]; 255 unsigned char vd_aux[4]; 256 unsigned char vd_next[4]; 257 } Elf_External_Verdef; 258 259 /* This structure appears in a SHT_GNU_verdef section. */ 260 261 typedef struct { 262 unsigned char vda_name[4]; 263 unsigned char vda_next[4]; 264 } Elf_External_Verdaux; 265 266 /* This structure appears in a SHT_GNU_verneed section. */ 267 268 typedef struct { 269 unsigned char vn_version[2]; 270 unsigned char vn_cnt[2]; 271 unsigned char vn_file[4]; 272 unsigned char vn_aux[4]; 273 unsigned char vn_next[4]; 274 } Elf_External_Verneed; 275 276 /* This structure appears in a SHT_GNU_verneed section. */ 277 278 typedef struct { 279 unsigned char vna_hash[4]; 280 unsigned char vna_flags[2]; 281 unsigned char vna_other[2]; 282 unsigned char vna_name[4]; 283 unsigned char vna_next[4]; 284 } Elf_External_Vernaux; 285 286 /* This structure appears in a SHT_GNU_versym section. This is not a 287 standard ELF structure; ELF just uses Elf32_Half. */ 288 289 typedef struct { 290 unsigned char vs_vers[2]; 291 } ATTRIBUTE_PACKED Elf_External_Versym; 292 293 /* Structure for syminfo section. */ 294 typedef struct 295 { 296 unsigned char si_boundto[2]; 297 unsigned char si_flags[2]; 298 } Elf_External_Syminfo; 299 300 301 /* This structure appears on the stack and in NT_AUXV core file notes. */ 302 typedef struct 303 { 304 unsigned char a_type[4]; 305 unsigned char a_val[4]; 306 } Elf32_External_Auxv; 307 308 typedef struct 309 { 310 unsigned char a_type[8]; 311 unsigned char a_val[8]; 312 } Elf64_External_Auxv; 313 314 /* Size of SHT_GROUP section entry. */ 315 316 #define GRP_ENTRY_SIZE 4 317 318 #endif /* _ELF_EXTERNAL_H */ 319