diff options
Diffstat (limited to 'grub-core/kern/elfXX.c')
| -rw-r--r-- | grub-core/kern/elfXX.c | 207 |
1 files changed, 207 insertions, 0 deletions
diff --git a/grub-core/kern/elfXX.c b/grub-core/kern/elfXX.c new file mode 100644 index 0000000..1859d18 --- /dev/null +++ b/grub-core/kern/elfXX.c @@ -0,0 +1,207 @@ +int +grub_elf_is_elfXX (grub_elf_t elf) +{ + return elf->ehdr.ehdrXX.e_ident[EI_CLASS] == ELFCLASSXX; +} + +grub_err_t +grub_elfXX_load_phdrs (grub_elf_t elf) +{ + grub_ssize_t phdrs_size; + + if (elf->phdrs) + return GRUB_ERR_NONE; + + phdrs_size = (grub_uint32_t) elf->ehdr.ehdrXX.e_phnum * elf->ehdr.ehdrXX.e_phentsize; + + grub_dprintf ("elf", "Loading program headers at 0x%llx, size 0x%lx.\n", + (unsigned long long) elf->ehdr.ehdrXX.e_phoff, + (unsigned long) phdrs_size); + + elf->phdrs = grub_malloc (phdrs_size); + if (! elf->phdrs) + return grub_errno; + + if ((grub_file_seek (elf->file, elf->ehdr.ehdrXX.e_phoff) == (grub_off_t) -1) + || (grub_file_read (elf->file, elf->phdrs, phdrs_size) != phdrs_size)) + { + if (!grub_errno) + grub_error (GRUB_ERR_FILE_READ_ERROR, N_("premature end of file %s"), + elf->filename); + return grub_errno; + } + +#if GRUB_ELF_ENABLE_BI_ENDIAN + if (elf->ehdr.ehdrXX.e_ident[EI_DATA] == GRUB_ELF_OPPOSITE_ENDIANNESS) + { + ElfXX_Phdr *phdr; + for (phdr = elf->phdrs; (char *) phdr < (char *) elf->phdrs + phdrs_size; + phdr = (ElfXX_Phdr *) ((char *) phdr + elf->ehdr.ehdrXX.e_phentsize)) + { + phdr->p_type = grub_swap_bytes_wordXX (phdr->p_type); + phdr->p_flags = grub_swap_bytes_wordXX (phdr->p_flags); + phdr->p_offset = grub_swap_bytes_offXX (phdr->p_offset); + phdr->p_vaddr = grub_swap_bytes_addrXX (phdr->p_vaddr); + phdr->p_paddr = grub_swap_bytes_addrXX (phdr->p_paddr); + phdr->p_filesz = grub_swap_bytes_XwordXX (phdr->p_filesz); + phdr->p_memsz = grub_swap_bytes_XwordXX (phdr->p_memsz); + phdr->p_align = grub_swap_bytes_XwordXX (phdr->p_align); + } + } +#endif /* GRUB_ELF_ENABLE_BI_ENDIAN */ + + return GRUB_ERR_NONE; +} + +/* Calculate the amount of memory spanned by the segments. */ +grub_size_t +grub_elfXX_size (grub_elf_t elf, + ElfXX_Addr *base, grub_uintXX_t *max_align) +{ + ElfXX_Addr segments_start = (ElfXX_Addr) -1; + ElfXX_Addr segments_end = 0; + int nr_phdrs = 0; + grub_uint32_t curr_align = 1; + ElfXX_Phdr *phdr; + + /* Run through the program headers to calculate the total memory size we + * should claim. */ + FOR_ELFXX_PHDRS (elf, phdr) + { + /* Only consider loadable segments. */ + if (phdr->p_type != PT_LOAD) + continue; + nr_phdrs++; + if (phdr->p_paddr < segments_start) + segments_start = phdr->p_paddr; + if (phdr->p_paddr + phdr->p_memsz > segments_end) + segments_end = phdr->p_paddr + phdr->p_memsz; + if (curr_align < phdr->p_align) + curr_align = phdr->p_align; + } + + if (base) + *base = 0; + + if (nr_phdrs == 0) + { + grub_error (GRUB_ERR_BAD_OS, "no program headers present"); + return 0; + } + + if (segments_end < segments_start) + { + /* Very bad addresses. */ + grub_error (GRUB_ERR_BAD_OS, "bad program header load addresses"); + return 0; + } + + if (base) + *base = segments_start; + if (max_align) + *max_align = curr_align; + return segments_end - segments_start; +} + +grub_err_t +grub_elfXX_load (grub_elf_t elf, const char *filename, + void *load_offset, enum grub_elf_load_flags load_flags, + grub_addr_t *base, grub_size_t *size) +{ + grub_addr_t load_base = (grub_addr_t) -1ULL; + grub_size_t load_size = 0; + ElfXX_Phdr *phdr; + + FOR_ELFXX_PHDRS(elf, phdr) + { + grub_addr_t load_addr; + + if (phdr->p_type != PT_LOAD && !((load_flags & GRUB_ELF_LOAD_FLAGS_LOAD_PT_DYNAMIC) && phdr->p_type == PT_DYNAMIC)) + continue; + + load_addr = (grub_addr_t) phdr->p_paddr; + switch (load_flags & GRUB_ELF_LOAD_FLAGS_BITS) + { + case GRUB_ELF_LOAD_FLAGS_ALL_BITS: + break; + case GRUB_ELF_LOAD_FLAGS_28BITS: + load_addr &= 0xFFFFFFF; + break; + case GRUB_ELF_LOAD_FLAGS_30BITS: + load_addr &= 0x3FFFFFFF; + break; + case GRUB_ELF_LOAD_FLAGS_62BITS: + load_addr &= 0x3FFFFFFFFFFFFFFFULL; + break; + } + load_addr += (grub_addr_t) load_offset; + + if (load_addr < load_base) + load_base = load_addr; + + grub_dprintf ("elf", "Loading segment at 0x%llx, size 0x%llx\n", + (unsigned long long) load_addr, + (unsigned long long) phdr->p_memsz); + + if (grub_file_seek (elf->file, phdr->p_offset) == (grub_off_t) -1) + return grub_errno; + + if (phdr->p_filesz) + { + grub_ssize_t read; + read = grub_file_read (elf->file, (void *) load_addr, phdr->p_filesz); + if (read != (grub_ssize_t) phdr->p_filesz) + { + if (!grub_errno) + grub_error (GRUB_ERR_FILE_READ_ERROR, N_("premature end of file %s"), + filename); + return grub_errno; + } + } + + if (phdr->p_filesz < phdr->p_memsz) + grub_memset ((void *) (grub_addr_t) (load_addr + phdr->p_filesz), + 0, phdr->p_memsz - phdr->p_filesz); + + load_size += phdr->p_memsz; + } + + if (base) + *base = load_base; + if (size) + *size = load_size; + + return grub_errno; +} + +static int +grub_elfXX_check_endianess_and_bswap_ehdr (grub_elf_t elf) +{ + ElfXX_Ehdr *e = &(elf->ehdr.ehdrXX); + if (e->e_ident[EI_DATA] == GRUB_ELF_NATIVE_ENDIANNESS) + { + return 1; + } + +#if GRUB_ELF_ENABLE_BI_ENDIAN + if (e->e_ident[EI_DATA] == GRUB_ELF_OPPOSITE_ENDIANNESS) + { + e->e_type = grub_swap_bytes_halfXX (e->e_type); + e->e_machine = grub_swap_bytes_halfXX (e->e_machine); + e->e_version = grub_swap_bytes_wordXX (e->e_version); + e->e_entry = grub_swap_bytes_addrXX (e->e_entry); + e->e_phoff = grub_swap_bytes_offXX (e->e_phoff); + e->e_shoff = grub_swap_bytes_offXX (e->e_shoff); + e->e_flags = grub_swap_bytes_wordXX (e->e_flags); + e->e_ehsize = grub_swap_bytes_halfXX (e->e_ehsize); + e->e_phentsize = grub_swap_bytes_halfXX (e->e_phentsize); + e->e_phnum = grub_swap_bytes_halfXX (e->e_phnum); + e->e_shentsize = grub_swap_bytes_halfXX (e->e_shentsize); + e->e_shnum = grub_swap_bytes_halfXX (e->e_shnum); + e->e_shstrndx = grub_swap_bytes_halfXX (e->e_shstrndx); + return 1; + } +#endif /* GRUB_ELF_ENABLE_BI_ENDIAN */ + + return 0; +} |