util/grub-macho2img.c

   1 /* macho2img.c - tool to convert Mach-O to raw imagw.  */
   2 /*
   3  *  GRUB  --  GRand Unified Bootloader
   4  *  Copyright (C) 2009 Free Software Foundation, Inc.
   5  *
   6  *  GRUB is free software: you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation, either version 3 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  GRUB is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include <grub/types.h>
  21 #include <grub/macho.h>
  22 #include <stdio.h>
  23 #include <string.h>
  24 #include <stdlib.h>
  25
  26 /* XXX: this file assumes particular Mach-O layout and does no checks. */
  27 /* However as build system ensures correct usage of this tool this
  28    shouldn't be a problem. */
  29
  30 int
  31 main (int argc, char **argv)
  32 {
  33   FILE *in, *out;
  34   int do_bss = 0;
  35   char *buf;
  36   int bufsize;
  37   struct grub_macho_header32 *head;
  38   struct grub_macho_segment32 *curcmd;
  39   unsigned i;
  40   unsigned bssstart = 0;
  41   unsigned bssend = 0;
  42
  43   if (argc && strcmp (argv[1], "--bss") == 0)
  44     do_bss = 1;
  45   if (argc < 2 + do_bss)
  46     {
  47       printf ("Usage: %s [--bss] filename.exec filename.img\n"
  48               "Convert Mach-O into raw image\n", argv[0]);
  49       return 0;
  50     }
  51   in = fopen (argv[1 + do_bss], "rb");
  52   if (! in)
  53     {
  54       printf ("Couldn't open %s\n", argv[1 + do_bss]);
  55       return 1;
  56     }
  57   out = fopen (argv[2 + do_bss], "wb");
  58   if (! out)
  59     {
  60       fclose (in);
  61       printf ("Couldn't open %s\n", argv[2 + do_bss]);
  62       return 2;
  63     }
  64   fseek (in, 0, SEEK_END);
  65   bufsize = ftell (in);
  66   fseek (in, 0, SEEK_SET);
  67   buf = malloc (bufsize);
  68   if (! buf)
  69     {
  70       fclose (in);
  71       fclose (out);
  72       printf ("Couldn't allocate buffer\n");
  73       return 3;
  74     }
  75   fread (buf, 1, bufsize, in);
  76   head = (struct grub_macho_header32 *) buf;
  77   if (grub_le_to_cpu32 (head->magic) != GRUB_MACHO_MAGIC32)
  78     {
  79       fclose (in);
  80       fclose (out);
  81       free (buf);
  82       printf ("Invalid Mach-O fle\n");
  83       return 4;
  84     }
  85   curcmd = (struct grub_macho_segment32 *) (buf + sizeof (*head));
  86   for (i = 0; i < grub_le_to_cpu32 (head->ncmds); i++,
  87          curcmd = (struct grub_macho_segment32 *)
  88          (((char *) curcmd) + curcmd->cmdsize))
  89     {
  90       if (curcmd->cmd != GRUB_MACHO_CMD_SEGMENT32)
  91         continue;
  92       fwrite (buf + grub_le_to_cpu32 (curcmd->fileoff), 1,
  93               grub_le_to_cpu32 (curcmd->filesize), out);
  94       if (grub_le_to_cpu32 (curcmd->vmsize)
  95           > grub_le_to_cpu32 (curcmd->filesize))
  96         {
  97           bssstart = grub_le_to_cpu32 (curcmd->vmaddr)
  98             + grub_le_to_cpu32 (curcmd->filesize) ;
  99           bssend = grub_le_to_cpu32 (curcmd->vmaddr)
 100             + grub_le_to_cpu32 (curcmd->vmsize) ;
 101         }
 102     }
 103   if (do_bss)
 104     {
 105       grub_uint32_t tmp;
 106       fseek (out, 0x5c, SEEK_SET);
 107       tmp = grub_cpu_to_le32 (bssstart);
 108       fwrite (&tmp, 4, 1, out);
 109       tmp = grub_cpu_to_le32 (bssend);
 110       fwrite (&tmp, 4, 1, out);
 111     }
 112   fclose (in);
 113   fclose (out);
 114   printf("macho2img complete\n");
 115   return 0;
 116 }