gnuefi/reloc_ia32.c

   1 /* reloc_ia32.c - position independent x86 ELF shared object relocator
   2    Copyright (C) 1999 Hewlett-Packard Co.
   3         Contributed by David Mosberger <davidm@hpl.hp.com>.
   4
   5     All rights reserved.
   6
   7     Redistribution and use in source and binary forms, with or without
   8     modification, are permitted provided that the following conditions
   9     are met:
  10
  11     * Redistributions of source code must retain the above copyright
  12       notice, this list of conditions and the following disclaimer.
  13     * Redistributions in binary form must reproduce the above
  14       copyright notice, this list of conditions and the following
  15       disclaimer in the documentation and/or other materials
  16       provided with the distribution.
  17     * Neither the name of Hewlett-Packard Co. nor the names of its
  18       contributors may be used to endorse or promote products derived
  19       from this software without specific prior written permission.
  20
  21     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
  22     CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
  23     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  24     MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  25     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
  26     BE LIABLE FOR ANYDIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
  27     OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  28     PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  29     PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  30     THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
  31     TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
  32     THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33     SUCH DAMAGE.
  34 */
  35
  36 #include <efi.h>
  37 #include <efilib.h>
  38
  39 #include <elf.h>
  40
  41 EFI_STATUS _relocate (long ldbase, Elf32_Dyn *dyn,
  42                       EFI_HANDLE image EFI_UNUSED,
  43                       EFI_SYSTEM_TABLE *systab EFI_UNUSED)
  44 {
  45         long relsz = 0, relent = 0;
  46         Elf32_Rel *rel = 0;
  47         unsigned long *addr;
  48         int i;
  49
  50         for (i = 0; dyn[i].d_tag != DT_NULL; ++i) {
  51                 switch (dyn[i].d_tag) {
  52                         case DT_REL:
  53                                 rel = (Elf32_Rel*)
  54                                         ((unsigned long)dyn[i].d_un.d_ptr
  55                                          + ldbase);
  56                                 break;
  57
  58                         case DT_RELSZ:
  59                                 relsz = dyn[i].d_un.d_val;
  60                                 break;
  61
  62                         case DT_RELENT:
  63                                 relent = dyn[i].d_un.d_val;
  64                                 break;
  65
  66                         case DT_RELA:
  67                                 break;
  68
  69                         default:
  70                                 break;
  71                 }
  72         }
  73
  74         if (!rel && relent == 0)
  75                 return EFI_SUCCESS;
  76
  77         if (!rel || relent == 0)
  78                 return EFI_LOAD_ERROR;
  79
  80         while (relsz > 0) {
  81                 /* apply the relocs */
  82                 switch (ELF32_R_TYPE (rel->r_info)) {
  83                         case R_386_NONE:
  84                                 break;
  85
  86                         case R_386_RELATIVE:
  87                                 addr = (unsigned long *)
  88                                         (ldbase + rel->r_offset);
  89                                 *addr += ldbase;
  90                                 break;
  91
  92                         default:
  93                                 break;
  94                 }
  95                 rel = (Elf32_Rel*) ((char *) rel + relent);
  96                 relsz -= relent;
  97         }
  98         return EFI_SUCCESS;
  99 }