diff options
Diffstat (limited to 'grub-core/loader/multiboot_elfxx.c')
| -rw-r--r-- | grub-core/loader/multiboot_elfxx.c | 225 |
1 files changed, 225 insertions, 0 deletions
diff --git a/grub-core/loader/multiboot_elfxx.c b/grub-core/loader/multiboot_elfxx.c new file mode 100644 index 0000000..0c29fe9 --- /dev/null +++ b/grub-core/loader/multiboot_elfxx.c @@ -0,0 +1,225 @@ +/* + * 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 <http://www.gnu.org/licenses/>. + */ + +#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 <grub/i386/relocator.h> + +#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"); + +#if defined (MULTIBOOT_LOAD_ELF64) && defined (__mips) + /* We still in 32-bit mode. */ + if (ehdr->e_entry < 0xffffffff80000000ULL) + return grub_error (GRUB_ERR_BAD_OS, "invalid entry point for ELF64"); +#else + /* 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) + { + 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 (phdr(i)->p_filesz != 0) + { + 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 defined (__i386__) || defined (__x86_64__) + +#elif defined (__mips) + grub_multiboot_payload_eip |= 0x80000000; +#else +#error Please complete this +#endif + + 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 |