diff options
Diffstat (limited to 'grub-core/loader/machoXX.c')
| -rw-r--r-- | grub-core/loader/machoXX.c | 239 |
1 files changed, 239 insertions, 0 deletions
diff --git a/grub-core/loader/machoXX.c b/grub-core/loader/machoXX.c new file mode 100644 index 0000000..918ddbb --- /dev/null +++ b/grub-core/loader/machoXX.c @@ -0,0 +1,239 @@ + +#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; +} |