com32/modules/i386-elf.h

   1 /*
   2  *  GRUB  --  GRand Unified Bootloader
   3  *  Copyright (C) 2001,2002  Free Software Foundation, Inc.
   4  *
   5  *  This program is free software; you can redistribute it and/or modify
   6  *  it under the terms of the GNU General Public License as published by
   7  *  the Free Software Foundation; either version 2 of the License, or
   8  *  (at your option) any later version.
   9  *
  10  *  This program is distributed in the hope that it will be useful,
  11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *  GNU General Public License for more details.
  14  *
  15  *  You should have received a copy of the GNU General Public License
  16  *  along with this program; if not, write to the Free Software
  17  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  18  */
  19
  20 /* 32-bit data types */
  21
  22 typedef unsigned long Elf32_Addr;
  23 typedef unsigned short Elf32_Half;
  24 typedef unsigned long Elf32_Off;
  25 typedef signed long Elf32_Sword;
  26 typedef unsigned long Elf32_Word;
  27 /* "unsigned char" already exists */
  28
  29 /* ELF header */
  30 typedef struct
  31 {
  32
  33 #define EI_NIDENT 16
  34
  35   /* first four characters are defined below */
  36 #define EI_MAG0         0
  37 #define ELFMAG0         0x7f
  38 #define EI_MAG1         1
  39 #define ELFMAG1         'E'
  40 #define EI_MAG2         2
  41 #define ELFMAG2         'L'
  42 #define EI_MAG3         3
  43 #define ELFMAG3         'F'
  44
  45 #define EI_CLASS        4       /* data sizes */
  46 #define ELFCLASS32      1       /* i386 -- up to 32-bit data sizes present */
  47
  48 #define EI_DATA         5       /* data type and ordering */
  49 #define ELFDATA2LSB     1       /* i386 -- LSB 2's complement */
  50
  51 #define EI_VERSION      6       /* version number.  "e_version" must be the same */
  52 #define EV_CURRENT      1       /* current version number */
  53
  54 #define EI_OSABI        7       /* operating system/ABI indication */
  55 #define ELFOSABI_FREEBSD        9
  56
  57 #define EI_ABIVERSION   8       /* ABI version */
  58
  59 #define EI_PAD          9       /* from here in is just padding */
  60
  61 #define EI_BRAND        8       /* start of OS branding (This is
  62                                    obviously illegal against the ELF
  63                                    standard.) */
  64
  65   unsigned char e_ident[EI_NIDENT];     /* basic identification block */
  66
  67 #define ET_EXEC         2       /* we only care about executable types */
  68   Elf32_Half e_type;            /* file types */
  69
  70 #define EM_386          3       /* i386 -- obviously use this one */
  71   Elf32_Half e_machine; /* machine types */
  72   Elf32_Word e_version; /* use same as "EI_VERSION" above */
  73   Elf32_Addr e_entry;           /* entry point of the program */
  74   Elf32_Off e_phoff;            /* program header table file offset */
  75   Elf32_Off e_shoff;            /* section header table file offset */
  76   Elf32_Word e_flags;           /* flags */
  77   Elf32_Half e_ehsize;          /* elf header size in bytes */
  78   Elf32_Half e_phentsize;       /* program header entry size */
  79   Elf32_Half e_phnum;           /* number of entries in program header */
  80   Elf32_Half e_shentsize;       /* section header entry size */
  81   Elf32_Half e_shnum;           /* number of entries in section header */
  82
  83 #define SHN_UNDEF       0
  84 #define SHN_LORESERVE   0xff00
  85 #define SHN_LOPROC      0xff00
  86 #define SHN_HIPROC      0xff1f
  87 #define SHN_ABS         0xfff1
  88 #define SHN_COMMON      0xfff2
  89 #define SHN_HIRESERVE   0xffff
  90   Elf32_Half e_shstrndx;        /* section header table index */
  91 }
  92 Elf32_Ehdr;
  93
  94
  95 #define BOOTABLE_I386_ELF(h) \
  96  ((h.e_ident[EI_MAG0] == ELFMAG0) & (h.e_ident[EI_MAG1] == ELFMAG1) \
  97   & (h.e_ident[EI_MAG2] == ELFMAG2) & (h.e_ident[EI_MAG3] == ELFMAG3) \
  98   & (h.e_ident[EI_CLASS] == ELFCLASS32) & (h.e_ident[EI_DATA] == ELFDATA2LSB) \
  99   & (h.e_ident[EI_VERSION] == EV_CURRENT) & (h.e_type == ET_EXEC) \
 100   & (h.e_machine == EM_386) & (h.e_version == EV_CURRENT))
 101
 102 /* section table - ? */
 103 typedef struct
 104 {
 105   Elf32_Word    sh_name;                /* Section name (string tbl index) */
 106   Elf32_Word    sh_type;                /* Section type */
 107   Elf32_Word    sh_flags;               /* Section flags */
 108   Elf32_Addr    sh_addr;                /* Section virtual addr at execution */
 109   Elf32_Off     sh_offset;              /* Section file offset */
 110   Elf32_Word    sh_size;                /* Section size in bytes */
 111   Elf32_Word    sh_link;                /* Link to another section */
 112   Elf32_Word    sh_info;                /* Additional section information */
 113   Elf32_Word    sh_addralign;           /* Section alignment */
 114   Elf32_Word    sh_entsize;             /* Entry size if section holds table */
 115 }
 116 Elf32_Shdr;
 117
 118 /* symbol table - page 4-25, figure 4-15 */
 119 typedef struct
 120 {
 121   Elf32_Word st_name;
 122   Elf32_Addr st_value;
 123   Elf32_Word st_size;
 124   unsigned char st_info;
 125   unsigned char st_other;
 126   Elf32_Half st_shndx;
 127 }
 128 Elf32_Sym;
 129
 130 /* symbol type and binding attributes - page 4-26 */
 131
 132 #define ELF32_ST_BIND(i)    ((i) >> 4)
 133 #define ELF32_ST_TYPE(i)    ((i) & 0xf)
 134 #define ELF32_ST_INFO(b,t)  (((b)<<4)+((t)&0xf))
 135
 136 /* symbol binding - page 4-26, figure 4-16 */
 137
 138 #define STB_LOCAL    0
 139 #define STB_GLOBAL   1
 140 #define STB_WEAK     2
 141 #define STB_LOPROC  13
 142 #define STB_HIPROC  15
 143
 144 /* symbol types - page 4-28, figure 4-17 */
 145
 146 #define STT_NOTYPE   0
 147 #define STT_OBJECT   1
 148 #define STT_FUNC     2
 149 #define STT_SECTION  3
 150 #define STT_FILE     4
 151 #define STT_LOPROC  13
 152 #define STT_HIPROC  15
 153
 154
 155 /* Macros to split/combine relocation type and symbol page 4-32 */
 156
 157 #define ELF32_R_SYM(__i)        ((__i)>>8)
 158 #define ELF32_R_TYPE(__i)       ((unsigned char) (__i))
 159 #define ELF32_R_INFO(__s, __t)  (((__s)<<8) + (unsigned char) (__t))
 160
 161
 162 /* program header - page 5-2, figure 5-1 */
 163
 164 typedef struct
 165 {
 166   Elf32_Word p_type;
 167   Elf32_Off p_offset;
 168   Elf32_Addr p_vaddr;
 169   Elf32_Addr p_paddr;
 170   Elf32_Word p_filesz;
 171   Elf32_Word p_memsz;
 172   Elf32_Word p_flags;
 173   Elf32_Word p_align;
 174 }
 175 Elf32_Phdr;
 176
 177 /* segment types - page 5-3, figure 5-2 */
 178
 179 #define PT_NULL         0
 180 #define PT_LOAD         1
 181 #define PT_DYNAMIC      2
 182 #define PT_INTERP       3
 183 #define PT_NOTE         4
 184 #define PT_SHLIB        5
 185 #define PT_PHDR         6
 186
 187 #define PT_LOPROC       0x70000000
 188 #define PT_HIPROC       0x7fffffff
 189
 190 /* segment permissions - page 5-6 */
 191
 192 #define PF_X            0x1
 193 #define PF_W            0x2
 194 #define PF_R            0x4
 195 #define PF_MASKPROC     0xf0000000
 196
 197
 198 /* dynamic structure - page 5-15, figure 5-9 */
 199
 200 typedef struct
 201 {
 202   Elf32_Sword d_tag;
 203   union
 204   {
 205     Elf32_Word d_val;
 206     Elf32_Addr d_ptr;
 207   }
 208   d_un;
 209 }
 210 Elf32_Dyn;
 211
 212 /* Dynamic array tags - page 5-16, figure 5-10.  */
 213
 214 #define DT_NULL         0
 215 #define DT_NEEDED       1
 216 #define DT_PLTRELSZ     2
 217 #define DT_PLTGOT       3
 218 #define DT_HASH         4
 219 #define DT_STRTAB       5
 220 #define DT_SYMTAB       6
 221 #define DT_RELA         7
 222 #define DT_RELASZ       8
 223 #define DT_RELAENT      9
 224 #define DT_STRSZ        10
 225 #define DT_SYMENT       11
 226 #define DT_INIT         12
 227 #define DT_FINI         13
 228 #define DT_SONAME       14
 229 #define DT_RPATH        15
 230 #define DT_SYMBOLIC     16
 231 #define DT_REL          17
 232 #define DT_RELSZ        18
 233 #define DT_RELENT       19
 234 #define DT_PLTREL       20
 235 #define DT_DEBUG        21
 236 #define DT_TEXTREL      22
 237 #define DT_JMPREL       23