/* * 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