grub/grub-core/loader/machoXX.c
2010-05-06 11:34:04 +05:30

239 lines
6.4 KiB
C

#include <grub/file.h>
#include <grub/mm.h>
#include <grub/misc.h>
#define min(a,b) (((a) < (b)) ? (a) : (b))
int
SUFFIX (grub_macho_contains_macho) (grub_macho_t macho)
{
return macho->offsetXX != -1;
}
void
SUFFIX (grub_macho_parse) (grub_macho_t macho)
{
grub_macho_header_t head;
/* Is there any candidate at all? */
if (macho->offsetXX == -1)
return;
/* Read header and check magic*/
if (grub_file_seek (macho->file, macho->offsetXX) == (grub_off_t) -1
|| grub_file_read (macho->file, &head, sizeof (head))
!= sizeof(head))
{
grub_error (GRUB_ERR_READ_ERROR, "cannot read Mach-O header");
macho->offsetXX = -1;
return;
}
if (head.magic != GRUB_MACHO_MAGIC)
{
grub_error (GRUB_ERR_BAD_OS, "invalid Mach-O " XX "-bit header");
macho->offsetXX = -1;
return;
}
/* Read commands. */
macho->ncmdsXX = head.ncmds;
macho->cmdsizeXX = head.sizeofcmds;
macho->cmdsXX = grub_malloc(macho->cmdsizeXX);
if (! macho->cmdsXX)
{
grub_error (GRUB_ERR_OUT_OF_MEMORY, "not enough memory to read commands");
return;
}
if (grub_file_read (macho->file, macho->cmdsXX,
(grub_size_t) macho->cmdsizeXX)
!= (grub_ssize_t) macho->cmdsizeXX)
{
grub_error (GRUB_ERR_READ_ERROR, "cannot read Mach-O header");
macho->offsetXX = -1;
}
}
typedef int NESTED_FUNC_ATTR (*grub_macho_iter_hook_t)
(grub_macho_t , struct grub_macho_cmd *,
void *);
static grub_err_t
grub_macho_cmds_iterate (grub_macho_t macho,
grub_macho_iter_hook_t hook,
void *hook_arg)
{
grub_uint8_t *hdrs = macho->cmdsXX;
int i;
if (! macho->cmdsXX)
return grub_error (GRUB_ERR_BAD_OS, "couldn't find " XX "-bit Mach-O");
for (i = 0; i < macho->ncmdsXX; i++)
{
struct grub_macho_cmd *hdr = (struct grub_macho_cmd *) hdrs;
if (hook (macho, hdr, hook_arg))
break;
hdrs += hdr->cmdsize;
}
return grub_errno;
}
grub_size_t
SUFFIX (grub_macho_filesize) (grub_macho_t macho)
{
if (SUFFIX (grub_macho_contains_macho) (macho))
return macho->endXX - macho->offsetXX;
return 0;
}
grub_err_t
SUFFIX (grub_macho_readfile) (grub_macho_t macho, void *dest)
{
grub_ssize_t read;
if (! SUFFIX (grub_macho_contains_macho) (macho))
return grub_error (GRUB_ERR_BAD_OS,
"couldn't read architecture-specific part");
if (grub_file_seek (macho->file, macho->offsetXX) == (grub_off_t) -1)
{
grub_error_push ();
return grub_error (GRUB_ERR_BAD_OS,
"invalid offset in program header");
}
read = grub_file_read (macho->file, dest,
macho->endXX - macho->offsetXX);
if (read != (grub_ssize_t) (macho->endXX - macho->offsetXX))
{
grub_error_push ();
return grub_error (GRUB_ERR_BAD_OS,
"couldn't read architecture-specific part");
}
return GRUB_ERR_NONE;
}
/* Calculate the amount of memory spanned by the segments. */
grub_err_t
SUFFIX (grub_macho_size) (grub_macho_t macho, grub_macho_addr_t *segments_start,
grub_macho_addr_t *segments_end, int flags)
{
int nr_phdrs = 0;
/* Run through the program headers to calculate the total memory size we
should claim. */
auto int NESTED_FUNC_ATTR calcsize (grub_macho_t _macho,
struct grub_macho_cmd *phdr, void *_arg);
int NESTED_FUNC_ATTR calcsize (grub_macho_t _macho __attribute__ ((unused)),
struct grub_macho_cmd *hdr0,
void *_arg __attribute__ ((unused)))
{
grub_macho_segment_t *hdr = (grub_macho_segment_t *) hdr0;
if (hdr->cmd != GRUB_MACHO_CMD_SEGMENT)
return 0;
if (! hdr->vmsize)
return 0;
if (! hdr->filesize && (flags & GRUB_MACHO_NOBSS))
return 0;
nr_phdrs++;
if (hdr->vmaddr < *segments_start)
*segments_start = hdr->vmaddr;
if (hdr->vmaddr + hdr->vmsize > *segments_end)
*segments_end = hdr->vmaddr + hdr->vmsize;
return 0;
}
*segments_start = (grub_macho_addr_t) -1;
*segments_end = 0;
grub_macho_cmds_iterate (macho, calcsize, 0);
if (nr_phdrs == 0)
return grub_error (GRUB_ERR_BAD_OS, "no program headers present");
if (*segments_end < *segments_start)
/* Very bad addresses. */
return grub_error (GRUB_ERR_BAD_OS, "bad program header load addresses");
return GRUB_ERR_NONE;
}
/* Load every loadable segment into memory specified by `_load_hook'. */
grub_err_t
SUFFIX (grub_macho_load) (grub_macho_t macho, char *offset, int flags)
{
grub_err_t err = 0;
auto int NESTED_FUNC_ATTR do_load(grub_macho_t _macho,
struct grub_macho_cmd *hdr0,
void *_arg __attribute__ ((unused)));
int NESTED_FUNC_ATTR do_load(grub_macho_t _macho,
struct grub_macho_cmd *hdr0,
void *_arg __attribute__ ((unused)))
{
grub_macho_segment_t *hdr = (grub_macho_segment_t *) hdr0;
if (hdr->cmd != GRUB_MACHO_CMD_SEGMENT)
return 0;
if (! hdr->filesize && (flags & GRUB_MACHO_NOBSS))
return 0;
if (! hdr->vmsize)
return 0;
if (grub_file_seek (_macho->file, hdr->fileoff
+ _macho->offsetXX) == (grub_off_t) -1)
{
grub_error_push ();
grub_error (GRUB_ERR_BAD_OS,
"invalid offset in program header");
return 1;
}
if (hdr->filesize)
{
grub_ssize_t read;
read = grub_file_read (_macho->file, offset + hdr->vmaddr,
min (hdr->filesize, hdr->vmsize));
if (read != (grub_ssize_t) min (hdr->filesize, hdr->vmsize))
{
/* XXX How can we free memory from `load_hook'? */
grub_error_push ();
err=grub_error (GRUB_ERR_BAD_OS,
"couldn't read segment from file: "
"wanted 0x%lx bytes; read 0x%lx bytes",
hdr->filesize, read);
return 1;
}
}
if (hdr->filesize < hdr->vmsize)
grub_memset (offset + hdr->vmaddr + hdr->filesize,
0, hdr->vmsize - hdr->filesize);
return 0;
}
grub_macho_cmds_iterate (macho, do_load, 0);
return err;
}
grub_macho_addr_t
SUFFIX (grub_macho_get_entry_point) (grub_macho_t macho)
{
grub_macho_addr_t entry_point = 0;
auto int NESTED_FUNC_ATTR hook(grub_macho_t _macho,
struct grub_macho_cmd *hdr,
void *_arg __attribute__ ((unused)));
int NESTED_FUNC_ATTR hook(grub_macho_t _macho __attribute__ ((unused)),
struct grub_macho_cmd *hdr,
void *_arg __attribute__ ((unused)))
{
if (hdr->cmd == GRUB_MACHO_CMD_THREAD)
entry_point = ((grub_macho_thread_t *) hdr)->entry_point;
return 0;
}
grub_macho_cmds_iterate (macho, hook, 0);
return entry_point;
}