/* * GRUB -- GRand Unified Bootloader * Copyright (C) 1999,2000,2001,2002,2003,2004,2005,2007,2008,2009 Free Software Foundation, Inc. * * GRUB 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 3 of the License, or * (at your option) any later version. * * GRUB 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 GRUB. If not, see . */ #if defined(MULTIBOOT_LOAD_ELF32) # define XX 32 # define E_MACHINE MULTIBOOT_ELF32_MACHINE # define ELFCLASSXX ELFCLASS32 # define Elf_Ehdr Elf32_Ehdr # define Elf_Phdr Elf32_Phdr #elif defined(MULTIBOOT_LOAD_ELF64) # define XX 64 # define E_MACHINE MULTIBOOT_ELF64_MACHINE # define ELFCLASSXX ELFCLASS64 # define Elf_Ehdr Elf64_Ehdr # define Elf_Phdr Elf64_Phdr #else #error "I'm confused" #endif #include #define CONCAT(a,b) CONCAT_(a, b) #define CONCAT_(a,b) a ## b /* Check if BUFFER contains ELF32 (or ELF64). */ static int CONCAT(grub_multiboot_is_elf, XX) (void *buffer) { Elf_Ehdr *ehdr = (Elf_Ehdr *) buffer; return ehdr->e_ident[EI_CLASS] == ELFCLASSXX; } static grub_err_t CONCAT(grub_multiboot_load_elf, XX) (grub_file_t file, void *buffer) { Elf_Ehdr *ehdr = (Elf_Ehdr *) buffer; char *phdr_base; int i; if (ehdr->e_ident[EI_CLASS] != ELFCLASSXX) return grub_error (GRUB_ERR_UNKNOWN_OS, "invalid ELF class"); if (ehdr->e_ident[EI_MAG0] != ELFMAG0 || ehdr->e_ident[EI_MAG1] != ELFMAG1 || ehdr->e_ident[EI_MAG2] != ELFMAG2 || ehdr->e_ident[EI_MAG3] != ELFMAG3 || ehdr->e_version != EV_CURRENT || ehdr->e_ident[EI_DATA] != ELFDATA2LSB || ehdr->e_machine != E_MACHINE) return grub_error(GRUB_ERR_UNKNOWN_OS, "no valid ELF header found"); if (ehdr->e_type != ET_EXEC && ehdr->e_type != ET_DYN) return grub_error (GRUB_ERR_UNKNOWN_OS, "invalid ELF file type"); /* FIXME: Should we support program headers at strange locations? */ if (ehdr->e_phoff + ehdr->e_phnum * ehdr->e_phentsize > MULTIBOOT_SEARCH) return grub_error (GRUB_ERR_BAD_OS, "program header at a too high offset"); #ifdef MULTIBOOT_LOAD_ELF64 /* We still in 32-bit mode. */ if (ehdr->e_entry > 0xffffffff) return grub_error (GRUB_ERR_BAD_OS, "invalid entry point for ELF64"); #endif phdr_base = (char *) buffer + ehdr->e_phoff; #define phdr(i) ((Elf_Phdr *) (phdr_base + (i) * ehdr->e_phentsize)) /* Load every loadable segment in memory. */ for (i = 0; i < ehdr->e_phnum; i++) { if (phdr(i)->p_type == PT_LOAD && phdr(i)->p_filesz != 0) { grub_err_t err; void *source; grub_dprintf ("multiboot_loader", "segment %d: paddr=0x%lx, memsz=0x%lx, vaddr=0x%lx\n", i, (long) phdr(i)->p_paddr, (long) phdr(i)->p_memsz, (long) phdr(i)->p_vaddr); { grub_relocator_chunk_t ch; err = grub_relocator_alloc_chunk_addr (grub_multiboot_relocator, &ch, phdr(i)->p_paddr, phdr(i)->p_memsz); if (err) { grub_dprintf ("multiboot_loader", "Error loading phdr %d\n", i); return err; } source = get_virtual_current_address (ch); } if (grub_file_seek (file, (grub_off_t) phdr(i)->p_offset) == (grub_off_t) -1) return grub_error (GRUB_ERR_BAD_OS, "invalid offset in program header"); if (grub_file_read (file, source, phdr(i)->p_filesz) != (grub_ssize_t) phdr(i)->p_filesz) return grub_error (GRUB_ERR_BAD_OS, "couldn't read segment from file"); if (phdr(i)->p_filesz < phdr(i)->p_memsz) grub_memset ((grub_uint8_t *) source + phdr(i)->p_filesz, 0, phdr(i)->p_memsz - phdr(i)->p_filesz); } } for (i = 0; i < ehdr->e_phnum; i++) if (phdr(i)->p_vaddr <= ehdr->e_entry && phdr(i)->p_vaddr + phdr(i)->p_memsz > ehdr->e_entry) { grub_multiboot_payload_eip = (ehdr->e_entry - phdr(i)->p_vaddr) + phdr(i)->p_paddr; break; } if (i == ehdr->e_phnum) return grub_error (GRUB_ERR_BAD_OS, "entry point isn't in a segment"); if (ehdr->e_shnum) { grub_uint8_t *shdr, *shdrptr; shdr = grub_malloc (ehdr->e_shnum * ehdr->e_shentsize); if (!shdr) return grub_errno; if (grub_file_seek (file, ehdr->e_shoff) == (grub_off_t) -1) return grub_error (GRUB_ERR_BAD_OS, "invalid offset to section headers"); if (grub_file_read (file, shdr, ehdr->e_shnum * ehdr->e_shentsize) != (grub_ssize_t) ehdr->e_shnum * ehdr->e_shentsize) return grub_error (GRUB_ERR_BAD_OS, "couldn't read sections headers from file"); for (shdrptr = shdr, i = 0; i < ehdr->e_shnum; shdrptr += ehdr->e_shentsize, i++) { Elf_Shdr *sh = (Elf_Shdr *) shdrptr; void *src; grub_addr_t target; grub_err_t err; /* This section is a loaded section, so we don't care. */ if (sh->sh_addr != 0) continue; /* This section is empty, so we don't care. */ if (sh->sh_size == 0) continue; { grub_relocator_chunk_t ch; err = grub_relocator_alloc_chunk_align (grub_multiboot_relocator, &ch, 0, (0xffffffff - sh->sh_size) + 1, sh->sh_size, sh->sh_addralign, GRUB_RELOCATOR_PREFERENCE_NONE); if (err) { grub_dprintf ("multiboot_loader", "Error loading shdr %d\n", i); return err; } src = get_virtual_current_address (ch); target = get_physical_target_address (ch); } if (grub_file_seek (file, sh->sh_offset) == (grub_off_t) -1) return grub_error (GRUB_ERR_BAD_OS, "invalid offset in section header"); if (grub_file_read (file, src, sh->sh_size) != (grub_ssize_t) sh->sh_size) return grub_error (GRUB_ERR_BAD_OS, "couldn't read segment from file"); sh->sh_addr = target; } grub_multiboot_add_elfsyms (ehdr->e_shnum, ehdr->e_shentsize, ehdr->e_shstrndx, shdr); } #undef phdr return grub_errno; } #undef XX #undef E_MACHINE #undef ELFCLASSXX #undef Elf_Ehdr #undef Elf_Phdr