From 1eb395fea007c7b86a72cc264130fb5b2bbd6912 Mon Sep 17 00:00:00 2001 From: Paulo Flabiano Smorigo Date: Fri, 15 Aug 2014 14:39:53 -0300 Subject: [PATCH 53/74] Suport for bi-endianess in elf file * grub-core/kern/elf.c: check and switch endianess with grub_{be,le}_to cpu functions. * grub-core/kern/elfXX.c: Likewise. Also-by: Tomohiro B Berry --- grub-core/kern/elf.c | 60 +++++++++++++++++++++++++++++++++++++++-- grub-core/kern/elfXX.c | 73 ++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 131 insertions(+), 2 deletions(-) diff --git a/grub-core/kern/elf.c b/grub-core/kern/elf.c index 5f99c43..de90811 100644 --- a/grub-core/kern/elf.c +++ b/grub-core/kern/elf.c @@ -28,6 +28,11 @@ GRUB_MOD_LICENSE ("GPLv3+"); +void grub_elf32_check_endianess (grub_elf_t elf); +void grub_elf64_check_endianess (grub_elf_t elf); +grub_err_t grub_elf32_check_version (grub_elf_t elf); +grub_err_t grub_elf64_check_version (grub_elf_t elf); + /* Check if EHDR is a valid ELF header. */ static grub_err_t grub_elf_check_header (grub_elf_t elf) @@ -38,10 +43,22 @@ grub_elf_check_header (grub_elf_t elf) || e->e_ident[EI_MAG1] != ELFMAG1 || e->e_ident[EI_MAG2] != ELFMAG2 || e->e_ident[EI_MAG3] != ELFMAG3 - || e->e_ident[EI_VERSION] != EV_CURRENT - || e->e_version != EV_CURRENT) + || e->e_ident[EI_VERSION] != EV_CURRENT) return grub_error (GRUB_ERR_BAD_OS, N_("invalid arch-independent ELF magic")); + if (grub_elf_is_elf32 (elf)) + { + grub_elf32_check_endianess (elf); + grub_elf32_check_version (elf); + } + else if (grub_elf_is_elf64 (elf)) + { + grub_elf64_check_endianess (elf); + grub_elf64_check_version (elf); + } + else + return grub_error (GRUB_ERR_BAD_OS, N_("invalid arch-dependent ELF magic")); + return GRUB_ERR_NONE; } @@ -127,7 +144,20 @@ grub_elf_open (const char *name) #define grub_elf_is_elfXX grub_elf_is_elf32 #define grub_elfXX_load_phdrs grub_elf32_load_phdrs #define ElfXX_Phdr Elf32_Phdr +#define ElfXX_Ehdr Elf32_Ehdr #define grub_uintXX_t grub_uint32_t +#define grub_be_to_halfXX grub_be_to_cpu16 +#define grub_be_to_wordXX grub_be_to_cpu32 +#define grub_be_to_addrXX grub_be_to_cpu32 +#define grub_be_to_offXX grub_be_to_cpu32 +#define grub_be_to_XwordXX grub_be_to_wordXX +#define grub_le_to_halfXX grub_le_to_cpu16 +#define grub_le_to_wordXX grub_le_to_cpu32 +#define grub_le_to_addrXX grub_le_to_cpu32 +#define grub_le_to_offXX grub_le_to_cpu32 +#define grub_le_to_XwordXX grub_le_to_wordXX +#define grub_elfXX_check_endianess grub_elf32_check_endianess +#define grub_elfXX_check_version grub_elf32_check_version #include "elfXX.c" @@ -140,7 +170,20 @@ grub_elf_open (const char *name) #undef grub_elf_is_elfXX #undef grub_elfXX_load_phdrs #undef ElfXX_Phdr +#undef ElfXX_Ehdr #undef grub_uintXX_t +#undef grub_be_to_halfXX +#undef grub_be_to_wordXX +#undef grub_be_to_addrXX +#undef grub_be_to_offXX +#undef grub_be_to_XwordXX +#undef grub_le_to_halfXX +#undef grub_le_to_wordXX +#undef grub_le_to_addrXX +#undef grub_le_to_offXX +#undef grub_le_to_XwordXX +#undef grub_elfXX_check_endianess +#undef grub_elfXX_check_version /* 64-bit */ @@ -153,6 +196,19 @@ grub_elf_open (const char *name) #define grub_elf_is_elfXX grub_elf_is_elf64 #define grub_elfXX_load_phdrs grub_elf64_load_phdrs #define ElfXX_Phdr Elf64_Phdr +#define ElfXX_Ehdr Elf64_Ehdr #define grub_uintXX_t grub_uint64_t +#define grub_be_to_halfXX grub_be_to_cpu16 +#define grub_be_to_wordXX grub_be_to_cpu32 +#define grub_be_to_addrXX grub_be_to_cpu64 +#define grub_be_to_offXX grub_be_to_cpu64 +#define grub_be_to_XwordXX grub_be_to_cpu64 +#define grub_le_to_halfXX grub_le_to_cpu16 +#define grub_le_to_wordXX grub_le_to_cpu32 +#define grub_le_to_addrXX grub_le_to_cpu64 +#define grub_le_to_offXX grub_le_to_cpu64 +#define grub_le_to_XwordXX grub_le_to_cpu64 +#define grub_elfXX_check_endianess grub_elf64_check_endianess +#define grub_elfXX_check_version grub_elf64_check_version #include "elfXX.c" diff --git a/grub-core/kern/elfXX.c b/grub-core/kern/elfXX.c index 1d09971..ecf9df6 100644 --- a/grub-core/kern/elfXX.c +++ b/grub-core/kern/elfXX.c @@ -154,3 +154,76 @@ grub_elfXX_load (grub_elf_t elf, const char *filename, return grub_errno; } + +void +grub_elfXX_check_endianess (grub_elf_t elf) +{ + ElfXX_Ehdr *e = &(elf->ehdr.ehdrXX); + ElfXX_Phdr *phdr; + + if (e->e_ident[EI_DATA] == ELFDATA2MSB) + { + e->e_type = grub_be_to_halfXX (e->e_type); + e->e_machine = grub_be_to_halfXX (e->e_machine); + e->e_version = grub_be_to_wordXX (e->e_version); + e->e_entry = grub_be_to_addrXX (e->e_entry); + e->e_phoff = grub_be_to_offXX (e->e_phoff); + e->e_shoff = grub_be_to_offXX (e->e_shoff); + e->e_flags = grub_be_to_wordXX (e->e_flags); + e->e_ehsize = grub_be_to_halfXX (e->e_ehsize); + e->e_phentsize = grub_be_to_halfXX (e->e_phentsize); + e->e_phnum = grub_be_to_halfXX (e->e_phnum); + e->e_shentsize = grub_be_to_halfXX (e->e_shentsize); + e->e_shnum = grub_be_to_halfXX (e->e_shnum); + e->e_shstrndx = grub_be_to_halfXX (e->e_shstrndx); + + FOR_ELFXX_PHDRS (elf,phdr) + { + phdr->p_type = grub_be_to_wordXX (phdr->p_type); + phdr->p_flags = grub_be_to_wordXX (phdr->p_flags); + phdr->p_offset = grub_be_to_offXX (phdr->p_offset); + phdr->p_vaddr = grub_be_to_addrXX (phdr->p_vaddr); + phdr->p_paddr = grub_be_to_addrXX (phdr->p_paddr); + phdr->p_filesz = grub_be_to_XwordXX (phdr->p_filesz); + phdr->p_memsz = grub_be_to_XwordXX (phdr->p_memsz); + phdr->p_align = grub_be_to_XwordXX (phdr->p_align); + } + } + else if (e->e_ident[EI_DATA] == ELFDATA2LSB) + { + e->e_type = grub_le_to_halfXX (e->e_type); + e->e_machine = grub_le_to_halfXX (e->e_machine); + e->e_version = grub_le_to_wordXX (e->e_version); + e->e_entry = grub_le_to_addrXX (e->e_entry); + e->e_phoff = grub_le_to_offXX (e->e_phoff); + e->e_shoff = grub_le_to_offXX (e->e_shoff); + e->e_flags = grub_le_to_wordXX (e->e_flags); + e->e_ehsize = grub_le_to_halfXX (e->e_ehsize); + e->e_phentsize = grub_le_to_halfXX (e->e_phentsize); + e->e_phnum = grub_le_to_halfXX (e->e_phnum); + e->e_shentsize = grub_le_to_halfXX (e->e_shentsize); + e->e_shnum = grub_le_to_halfXX (e->e_shnum); + e->e_shstrndx = grub_le_to_halfXX (e->e_shstrndx); + + FOR_ELFXX_PHDRS (elf,phdr) + { + phdr->p_type = grub_le_to_wordXX (phdr->p_type); + phdr->p_flags = grub_le_to_wordXX (phdr->p_flags); + phdr->p_offset = grub_le_to_offXX (phdr->p_offset); + phdr->p_vaddr = grub_le_to_addrXX (phdr->p_vaddr); + phdr->p_paddr = grub_le_to_addrXX (phdr->p_paddr); + phdr->p_filesz = grub_le_to_XwordXX (phdr->p_filesz); + phdr->p_memsz = grub_le_to_XwordXX (phdr->p_memsz); + phdr->p_align = grub_le_to_XwordXX (phdr->p_align); + } + } +} + +grub_err_t +grub_elfXX_check_version (grub_elf_t elf) +{ + if (elf->ehdr.ehdrXX.e_version != EV_CURRENT) + return grub_error (GRUB_ERR_BAD_OS, N_("invalid arch-independent ELF magic")); + + return GRUB_ERR_NONE; +} -- 2.4.3