205 lines
5.5 KiB
C
205 lines
5.5 KiB
C
/*
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* GRUB -- GRand Unified Bootloader
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* Copyright (C) 1996 Erich Boleyn <erich@uruk.org>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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*/
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/* 32-bit data types */
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typedef unsigned long Elf32_Addr;
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typedef unsigned short Elf32_Half;
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typedef unsigned long Elf32_Off;
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typedef signed long Elf32_Sword;
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typedef unsigned long Elf32_Word;
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/* "unsigned char" already exists */
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/* ELF header */
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typedef struct {
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#define EI_NIDENT 16
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/* first four characters are defined below */
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#define EI_MAG0 0
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#define ELFMAG0 0x7f
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#define EI_MAG1 1
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#define ELFMAG1 'E'
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#define EI_MAG2 2
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#define ELFMAG2 'L'
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#define EI_MAG3 3
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#define ELFMAG3 'F'
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#define EI_CLASS 4 /* data sizes */
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#define ELFCLASS32 1 /* i386 -- up to 32-bit data sizes present */
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#define EI_DATA 5 /* data type and ordering */
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#define ELFDATA2LSB 1 /* i386 -- LSB 2's complement */
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#define EI_VERSION 6 /* version number. "e_version" must be the same */
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#define EV_CURRENT 1 /* current version number */
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#define EI_PAD 7 /* from here in is just padding */
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unsigned char e_ident[EI_NIDENT]; /* basic identification block */
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#define ET_EXEC 2 /* we only care about executable types */
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Elf32_Half e_type; /* file types */
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#define EM_386 3 /* i386 -- obviously use this one */
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Elf32_Half e_machine; /* machine types */
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Elf32_Word e_version; /* use same as "EI_VERSION" above */
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Elf32_Addr e_entry; /* entry point of the program */
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Elf32_Off e_phoff; /* program header table file offset */
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Elf32_Off e_shoff; /* section header table file offset */
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Elf32_Word e_flags; /* flags */
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Elf32_Half e_ehsize; /* elf header size in bytes */
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Elf32_Half e_phentsize; /* program header entry size */
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Elf32_Half e_phnum; /* number of entries in program header */
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Elf32_Half e_shentsize; /* section header entry size */
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Elf32_Half e_shnum; /* number of entries in section header */
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#define SHN_UNDEF 0
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#define SHN_LORESERVE 0xff00
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#define SHN_LOPROC 0xff00
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#define SHN_HIPROC 0xff1f
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#define SHN_ABS 0xfff1
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#define SHN_COMMON 0xfff2
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#define SHN_HIRESERVE 0xffff
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Elf32_Half e_shstrndx; /* section header table index */
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} Elf32_Ehdr;
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#define BOOTABLE_I386_ELF(h) \
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((h.e_ident[EI_MAG0] == ELFMAG0) & (h.e_ident[EI_MAG1] == ELFMAG1) \
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& (h.e_ident[EI_MAG2] == ELFMAG2) & (h.e_ident[EI_MAG3] == ELFMAG3) \
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& (h.e_ident[EI_CLASS] == ELFCLASS32) & (h.e_ident[EI_DATA] == ELFDATA2LSB) \
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& (h.e_ident[EI_VERSION] == EV_CURRENT) & (h.e_type == ET_EXEC) \
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& (h.e_machine == EM_386) & (h.e_version == EV_CURRENT))
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/* symbol table - page 4-25, figure 4-15 */
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typedef struct
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{
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Elf32_Word st_name;
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Elf32_Addr st_value;
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Elf32_Word st_size;
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unsigned char st_info;
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unsigned char st_other;
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Elf32_Half st_shndx;
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} Elf32_Sym;
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/* symbol type and binding attributes - page 4-26 */
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#define ELF32_ST_BIND(i) ((i) >> 4)
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#define ELF32_ST_TYPE(i) ((i) & 0xf)
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#define ELF32_ST_INFO(b,t) (((b)<<4)+((t)&0xf))
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/* symbol binding - page 4-26, figure 4-16 */
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#define STB_LOCAL 0
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#define STB_GLOBAL 1
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#define STB_WEAK 2
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#define STB_LOPROC 13
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#define STB_HIPROC 15
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/* symbol types - page 4-28, figure 4-17 */
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#define STT_NOTYPE 0
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#define STT_OBJECT 1
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#define STT_FUNC 2
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#define STT_SECTION 3
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#define STT_FILE 4
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#define STT_LOPROC 13
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#define STT_HIPROC 15
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/* Macros to split/combine relocation type and symbol page 4-32 */
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#define ELF32_R_SYM(__i) ((__i)>>8)
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#define ELF32_R_TYPE(__i) ((unsigned char) (__i))
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#define ELF32_R_INFO(__s, __t) (((__s)<<8) + (unsigned char) (__t))
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/* program header - page 5-2, figure 5-1 */
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typedef struct {
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Elf32_Word p_type;
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Elf32_Off p_offset;
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Elf32_Addr p_vaddr;
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Elf32_Addr p_paddr;
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Elf32_Word p_filesz;
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Elf32_Word p_memsz;
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Elf32_Word p_flags;
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Elf32_Word p_align;
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} Elf32_Phdr;
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/* segment types - page 5-3, figure 5-2 */
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#define PT_NULL 0
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#define PT_LOAD 1
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#define PT_DYNAMIC 2
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#define PT_INTERP 3
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#define PT_NOTE 4
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#define PT_SHLIB 5
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#define PT_PHDR 6
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#define PT_LOPROC 0x70000000
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#define PT_HIPROC 0x7fffffff
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/* segment permissions - page 5-6 */
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#define PF_X 0x1
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#define PF_W 0x2
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#define PF_R 0x4
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#define PF_MASKPROC 0xf0000000
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/* dynamic structure - page 5-15, figure 5-9 */
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typedef struct {
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Elf32_Sword d_tag;
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union {
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Elf32_Word d_val;
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Elf32_Addr d_ptr;
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} d_un;
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} Elf32_Dyn;
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/* Dynamic array tags - page 5-16, figure 5-10. */
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#define DT_NULL 0
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#define DT_NEEDED 1
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#define DT_PLTRELSZ 2
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#define DT_PLTGOT 3
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#define DT_HASH 4
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#define DT_STRTAB 5
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#define DT_SYMTAB 6
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#define DT_RELA 7
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#define DT_RELASZ 8
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#define DT_RELAENT 9
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#define DT_STRSZ 10
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#define DT_SYMENT 11
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#define DT_INIT 12
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#define DT_FINI 13
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#define DT_SONAME 14
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#define DT_RPATH 15
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#define DT_SYMBOLIC 16
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#define DT_REL 17
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#define DT_RELSZ 18
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#define DT_RELENT 19
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#define DT_PLTREL 20
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#define DT_DEBUG 21
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#define DT_TEXTREL 22
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#define DT_JMPREL 23
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