include/elf/external.h

   1 /* ELF support for BFD.
   2    Copyright (C) 1991-2014 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 /* Symbol table entry */
 139
 140 typedef struct {
 141   unsigned char st_name[4];             /* Symbol name, index in string tbl */
 142   unsigned char st_value[4];            /* Value of the symbol */
 143   unsigned char st_size[4];             /* Associated symbol size */
 144   unsigned char st_info[1];             /* Type and binding attributes */
 145   unsigned char st_other[1];            /* No defined meaning, 0 */
 146   unsigned char st_shndx[2];            /* Associated section index */
 147 } Elf32_External_Sym;
 148
 149 typedef struct {
 150   unsigned char st_name[4];             /* Symbol name, index in string tbl */
 151   unsigned char st_info[1];             /* Type and binding attributes */
 152   unsigned char st_other[1];            /* No defined meaning, 0 */
 153   unsigned char st_shndx[2];            /* Associated section index */
 154   unsigned char st_value[8];            /* Value of the symbol */
 155   unsigned char st_size[8];             /* Associated symbol size */
 156 } Elf64_External_Sym;
 157
 158 typedef struct {
 159   unsigned char est_shndx[4];           /* Section index */
 160 } Elf_External_Sym_Shndx;
 161
 162 /* Note segments */
 163
 164 typedef struct {
 165   unsigned char namesz[4];              /* Size of entry's owner string */
 166   unsigned char descsz[4];              /* Size of the note descriptor */
 167   unsigned char type[4];                /* Interpretation of the descriptor */
 168   char          name[1];                /* Start of the name+desc data */
 169 } Elf_External_Note;
 170
 171 /* Relocation Entries */
 172 typedef struct {
 173   unsigned char r_offset[4];    /* Location at which to apply the action */
 174   unsigned char r_info[4];      /* index and type of relocation */
 175 } Elf32_External_Rel;
 176
 177 typedef struct {
 178   unsigned char r_offset[4];    /* Location at which to apply the action */
 179   unsigned char r_info[4];      /* index and type of relocation */
 180   unsigned char r_addend[4];    /* Constant addend used to compute value */
 181 } Elf32_External_Rela;
 182
 183 typedef struct {
 184   unsigned char r_offset[8];    /* Location at which to apply the action */
 185   unsigned char r_info[8];      /* index and type of relocation */
 186 } Elf64_External_Rel;
 187
 188 typedef struct {
 189   unsigned char r_offset[8];    /* Location at which to apply the action */
 190   unsigned char r_info[8];      /* index and type of relocation */
 191   unsigned char r_addend[8];    /* Constant addend used to compute value */
 192 } Elf64_External_Rela;
 193
 194 /* dynamic section structure */
 195
 196 typedef struct {
 197   unsigned char d_tag[4];               /* entry tag value */
 198   union {
 199     unsigned char       d_val[4];
 200     unsigned char       d_ptr[4];
 201   } d_un;
 202 } Elf32_External_Dyn;
 203
 204 typedef struct {
 205   unsigned char d_tag[8];               /* entry tag value */
 206   union {
 207     unsigned char       d_val[8];
 208     unsigned char       d_ptr[8];
 209   } d_un;
 210 } Elf64_External_Dyn;
 211
 212 /* The version structures are currently size independent.  They are
 213    named without a 32 or 64.  If that ever changes, these structures
 214    will need to be renamed.  */
 215
 216 /* This structure appears in a SHT_GNU_verdef section.  */
 217
 218 typedef struct {
 219   unsigned char         vd_version[2];
 220   unsigned char         vd_flags[2];
 221   unsigned char         vd_ndx[2];
 222   unsigned char         vd_cnt[2];
 223   unsigned char         vd_hash[4];
 224   unsigned char         vd_aux[4];
 225   unsigned char         vd_next[4];
 226 } Elf_External_Verdef;
 227
 228 /* This structure appears in a SHT_GNU_verdef section.  */
 229
 230 typedef struct {
 231   unsigned char         vda_name[4];
 232   unsigned char         vda_next[4];
 233 } Elf_External_Verdaux;
 234
 235 /* This structure appears in a SHT_GNU_verneed section.  */
 236
 237 typedef struct {
 238   unsigned char         vn_version[2];
 239   unsigned char         vn_cnt[2];
 240   unsigned char         vn_file[4];
 241   unsigned char         vn_aux[4];
 242   unsigned char         vn_next[4];
 243 } Elf_External_Verneed;
 244
 245 /* This structure appears in a SHT_GNU_verneed section.  */
 246
 247 typedef struct {
 248   unsigned char         vna_hash[4];
 249   unsigned char         vna_flags[2];
 250   unsigned char         vna_other[2];
 251   unsigned char         vna_name[4];
 252   unsigned char         vna_next[4];
 253 } Elf_External_Vernaux;
 254
 255 /* This structure appears in a SHT_GNU_versym section.  This is not a
 256    standard ELF structure; ELF just uses Elf32_Half.  */
 257
 258 typedef struct {
 259   unsigned char         vs_vers[2];
 260 } ATTRIBUTE_PACKED  Elf_External_Versym;
 261
 262 /* Structure for syminfo section.  */
 263 typedef struct
 264 {
 265   unsigned char         si_boundto[2];
 266   unsigned char         si_flags[2];
 267 } Elf_External_Syminfo;
 268
 269
 270 /* This structure appears on the stack and in NT_AUXV core file notes.  */
 271 typedef struct
 272 {
 273   unsigned char         a_type[4];
 274   unsigned char         a_val[4];
 275 } Elf32_External_Auxv;
 276
 277 typedef struct
 278 {
 279   unsigned char         a_type[8];
 280   unsigned char         a_val[8];
 281 } Elf64_External_Auxv;
 282
 283 /* Size of SHT_GROUP section entry.  */
 284
 285 #define GRP_ENTRY_SIZE          4
 286
 287 #endif /* _ELF_EXTERNAL_H */