/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2001,2002 Free Software Foundation, Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
/* 32-bit data types */
typedef unsigned long Elf32_Addr;
typedef unsigned short Elf32_Half;
typedef unsigned long Elf32_Off;
typedef signed long Elf32_Sword;
typedef unsigned long Elf32_Word;
/* "unsigned char" already exists */
/* ELF header */
typedef struct
{
#define EI_NIDENT 16
/* first four characters are defined below */
#define EI_MAG0 0
#define ELFMAG0 0x7f
#define EI_MAG1 1
#define ELFMAG1 'E'
#define EI_MAG2 2
#define ELFMAG2 'L'
#define EI_MAG3 3
#define ELFMAG3 'F'
#define EI_CLASS 4 /* data sizes */
#define ELFCLASS32 1 /* i386 -- up to 32-bit data sizes present */
#define EI_DATA 5 /* data type and ordering */
#define ELFDATA2LSB 1 /* i386 -- LSB 2's complement */
#define EI_VERSION 6 /* version number. "e_version" must be the same */
#define EV_CURRENT 1 /* current version number */
#define EI_OSABI 7 /* operating system/ABI indication */
#define ELFOSABI_FREEBSD 9
#define EI_ABIVERSION 8 /* ABI version */
#define EI_PAD 9 /* from here in is just padding */
#define EI_BRAND 8 /* start of OS branding (This is
obviously illegal against the ELF
standard.) */
unsigned char e_ident[EI_NIDENT]; /* basic identification block */
#define ET_EXEC 2 /* we only care about executable types */
Elf32_Half e_type; /* file types */
#define EM_386 3 /* i386 -- obviously use this one */
Elf32_Half e_machine; /* machine types */
Elf32_Word e_version; /* use same as "EI_VERSION" above */
Elf32_Addr e_entry; /* entry point of the program */
Elf32_Off e_phoff; /* program header table file offset */
Elf32_Off e_shoff; /* section header table file offset */
Elf32_Word e_flags; /* flags */
Elf32_Half e_ehsize; /* elf header size in bytes */
Elf32_Half e_phentsize; /* program header entry size */
Elf32_Half e_phnum; /* number of entries in program header */
Elf32_Half e_shentsize; /* section header entry size */
Elf32_Half e_shnum; /* number of entries in section header */
#define SHN_UNDEF 0
#define SHN_LORESERVE 0xff00
#define SHN_LOPROC 0xff00
#define SHN_HIPROC 0xff1f
#define SHN_ABS 0xfff1
#define SHN_COMMON 0xfff2
#define SHN_HIRESERVE 0xffff
Elf32_Half e_shstrndx; /* section header table index */
}
Elf32_Ehdr;
#define BOOTABLE_I386_ELF(h) \
((h.e_ident[EI_MAG0] == ELFMAG0) & (h.e_ident[EI_MAG1] == ELFMAG1) \
& (h.e_ident[EI_MAG2] == ELFMAG2) & (h.e_ident[EI_MAG3] == ELFMAG3) \
& (h.e_ident[EI_CLASS] == ELFCLASS32) & (h.e_ident[EI_DATA] == ELFDATA2LSB) \
& (h.e_ident[EI_VERSION] == EV_CURRENT) & (h.e_type == ET_EXEC) \
& (h.e_machine == EM_386) & (h.e_version == EV_CURRENT))
/* section table - ? */
typedef struct
{
Elf32_Word sh_name; /* Section name (string tbl index) */
Elf32_Word sh_type; /* Section type */
Elf32_Word sh_flags; /* Section flags */
Elf32_Addr sh_addr; /* Section virtual addr at execution */
Elf32_Off sh_offset; /* Section file offset */
Elf32_Word sh_size; /* Section size in bytes */
Elf32_Word sh_link; /* Link to another section */
Elf32_Word sh_info; /* Additional section information */
Elf32_Word sh_addralign; /* Section alignment */
Elf32_Word sh_entsize; /* Entry size if section holds table */
}
Elf32_Shdr;
/* symbol table - page 4-25, figure 4-15 */
typedef struct
{
Elf32_Word st_name;
Elf32_Addr st_value;
Elf32_Word st_size;
unsigned char st_info;
unsigned char st_other;
Elf32_Half st_shndx;
}
Elf32_Sym;
/* symbol type and binding attributes - page 4-26 */
#define ELF32_ST_BIND(i) ((i) >> 4)
#define ELF32_ST_TYPE(i) ((i) & 0xf)
#define ELF32_ST_INFO(b,t) (((b)<<4)+((t)&0xf))
/* symbol binding - page 4-26, figure 4-16 */
#define STB_LOCAL 0
#define STB_GLOBAL 1
#define STB_WEAK 2
#define STB_LOPROC 13
#define STB_HIPROC 15
/* symbol types - page 4-28, figure 4-17 */
#define STT_NOTYPE 0
#define STT_OBJECT 1
#define STT_FUNC 2
#define STT_SECTION 3
#define STT_FILE 4
#define STT_LOPROC 13
#define STT_HIPROC 15
/* Macros to split/combine relocation type and symbol page 4-32 */
#define ELF32_R_SYM(__i) ((__i)>>8)
#define ELF32_R_TYPE(__i) ((unsigned char) (__i))
#define ELF32_R_INFO(__s, __t) (((__s)<<8) + (unsigned char) (__t))
/* program header - page 5-2, figure 5-1 */
typedef struct
{
Elf32_Word p_type;
Elf32_Off p_offset;
Elf32_Addr p_vaddr;
Elf32_Addr p_paddr;
Elf32_Word p_filesz;
Elf32_Word p_memsz;
Elf32_Word p_flags;
Elf32_Word p_align;
}
Elf32_Phdr;
/* segment types - page 5-3, figure 5-2 */
#define PT_NULL 0
#define PT_LOAD 1
#define PT_DYNAMIC 2
#define PT_INTERP 3
#define PT_NOTE 4
#define PT_SHLIB 5
#define PT_PHDR 6
#define PT_LOPROC 0x70000000
#define PT_HIPROC 0x7fffffff
/* segment permissions - page 5-6 */
#define PF_X 0x1
#define PF_W 0x2
#define PF_R 0x4
#define PF_MASKPROC 0xf0000000
/* dynamic structure - page 5-15, figure 5-9 */
typedef struct
{
Elf32_Sword d_tag;
union
{
Elf32_Word d_val;
Elf32_Addr d_ptr;
}
d_un;
}
Elf32_Dyn;
/* Dynamic array tags - page 5-16, figure 5-10. */
#define DT_NULL 0
#define DT_NEEDED 1
#define DT_PLTRELSZ 2
#define DT_PLTGOT 3
#define DT_HASH 4
#define DT_STRTAB 5
#define DT_SYMTAB 6
#define DT_RELA 7
#define DT_RELASZ 8
#define DT_RELAENT 9
#define DT_STRSZ 10
#define DT_SYMENT 11
#define DT_INIT 12
#define DT_FINI 13
#define DT_SONAME 14
#define DT_RPATH 15
#define DT_SYMBOLIC 16
#define DT_REL 17
#define DT_RELSZ 18
#define DT_RELENT 19
#define DT_PLTREL 20
#define DT_DEBUG 21
#define DT_TEXTREL 22
#define DT_JMPREL 23