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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;
}
grub_err_t
grub_elfXX_get_shnum (ElfXX_Ehdr *e, ElfXX_Shnum *shnum)
{
ElfXX_Shdr *s;
if (shnum == NULL)
return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("NULL pointer passed for shnum"));
/* Set *shnum to 0 so that shnum doesn't return junk on error */
*shnum = 0;
if (e == NULL)
return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("NULL pointer passed for elf header"));
*shnum = e->e_shnum;
if (*shnum == SHN_UNDEF)
{
if (e->e_shoff == 0)
return grub_error (GRUB_ERR_BAD_NUMBER, N_("invalid section header table offset in e_shoff"));
s = (ElfXX_Shdr *) ((grub_uint8_t *) e + e->e_shoff);
*shnum = s->sh_size;
if (*shnum < SHN_LORESERVE)
return grub_error (GRUB_ERR_BAD_NUMBER, N_("invalid number of section header table entries in sh_size: %" PRIuGRUB_UINT64_T), (grub_uint64_t) *shnum);
}
else
{
if (*shnum >= SHN_LORESERVE)
return grub_error (GRUB_ERR_BAD_NUMBER, N_("invalid number of section header table entries in e_shnum: %" PRIuGRUB_UINT64_T), (grub_uint64_t) *shnum);
}
return GRUB_ERR_NONE;
}
grub_err_t
grub_elfXX_get_shstrndx (ElfXX_Ehdr *e, ElfXX_Word *shstrndx)
{
ElfXX_Shdr *s;
if (shstrndx == NULL)
return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("NULL pointer passed for shstrndx"));
/* Set *shstrndx to 0 so that shstrndx doesn't return junk on error */
*shstrndx = 0;
if (e == NULL)
return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("NULL pointer passed for elf header"));
*shstrndx = e->e_shstrndx;
if (*shstrndx == SHN_XINDEX)
{
if (e->e_shoff == 0)
return grub_error (GRUB_ERR_BAD_NUMBER, N_("invalid section header table offset in e_shoff"));
s = (ElfXX_Shdr *) ((grub_uint8_t *) e + e->e_shoff);
*shstrndx = s->sh_link;
if (*shstrndx < SHN_LORESERVE)
return grub_error (GRUB_ERR_BAD_NUMBER, N_("invalid section header table index in sh_link: %d"), *shstrndx);
}
else
{
if (*shstrndx >= SHN_LORESERVE)
return grub_error (GRUB_ERR_BAD_NUMBER, N_("invalid section header table index in e_shstrndx: %d"), *shstrndx);
}
return GRUB_ERR_NONE;
}
grub_err_t
grub_elfXX_get_phnum (ElfXX_Ehdr *e, ElfXX_Word *phnum)
{
ElfXX_Shdr *s;
if (phnum == NULL)
return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("NULL pointer passed for phnum"));
/* Set *phnum to 0 so that phnum doesn't return junk on error */
*phnum = 0;
if (e == NULL)
return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("NULL pointer passed for elf header"));
*phnum = e->e_phnum;
if (*phnum == PN_XNUM)
{
if (e->e_shoff == 0)
return grub_error (GRUB_ERR_BAD_NUMBER, N_("invalid section header table offset in e_shoff"));
s = (ElfXX_Shdr *) ((grub_uint8_t *) e + e->e_shoff);
*phnum = s->sh_info;
if (*phnum < PN_XNUM)
return grub_error (GRUB_ERR_BAD_NUMBER, N_("invalid number of program header table entries in sh_info: %d"), *phnum);
}
else
{
if (*phnum >= PN_XNUM)
return grub_error (GRUB_ERR_BAD_NUMBER, N_("invalid number of program header table entries in e_phnum: %d"), *phnum);
}
return GRUB_ERR_NONE;
}
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