gnuefi/reloc_arm.c

   1 /* reloc_arm.c - position independent x86 ELF shared object relocator
   2    Copyright (C) 2014 Linaro Ltd. <ard.biesheuvel@linaro.org>
   3    Copyright (C) 1999 Hewlett-Packard Co.
   4         Contributed by David Mosberger <davidm@hpl.hp.com>.
   5
   6     All rights reserved.
   7
   8     Redistribution and use in source and binary forms, with or without
   9     modification, are permitted provided that the following conditions
  10     are met:
  11
  12     * Redistributions of source code must retain the above copyright
  13       notice, this list of conditions and the following disclaimer.
  14     * Redistributions in binary form must reproduce the above
  15       copyright notice, this list of conditions and the following
  16       disclaimer in the documentation and/or other materials
  17       provided with the distribution.
  18     * Neither the name of Hewlett-Packard Co. nor the names of its
  19       contributors may be used to endorse or promote products derived
  20       from this software without specific prior written permission.
  21
  22     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
  23     CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
  24     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  25     MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  26     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
  27     BE LIABLE FOR ANYDIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
  28     OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  29     PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  30     PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  31     THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
  32     TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
  33     THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  34     SUCH DAMAGE.
  35 */
  36
  37 #include <efi.h>
  38 #include <efilib.h>
  39
  40 #include <elf.h>
  41
  42 EFI_STATUS _relocate (long ldbase, Elf32_Dyn *dyn,
  43                       EFI_HANDLE image EFI_UNUSED,
  44                       EFI_SYSTEM_TABLE *systab EFI_UNUSED)
  45 {
  46         long relsz = 0, relent = 0;
  47         Elf32_Rel *rel = 0;
  48         unsigned long *addr;
  49         int i;
  50
  51         for (i = 0; dyn[i].d_tag != DT_NULL; ++i) {
  52                 switch (dyn[i].d_tag) {
  53                         case DT_REL:
  54                                 rel = (Elf32_Rel*)
  55                                         ((unsigned long)dyn[i].d_un.d_ptr
  56                                          + ldbase);
  57                                 break;
  58
  59                         case DT_RELSZ:
  60                                 relsz = dyn[i].d_un.d_val;
  61                                 break;
  62
  63                         case DT_RELENT:
  64                                 relent = dyn[i].d_un.d_val;
  65                                 break;
  66
  67                         default:
  68                                 break;
  69                 }
  70         }
  71
  72         if (!rel && relent == 0)
  73                 return EFI_SUCCESS;
  74
  75         if (!rel || relent == 0)
  76                 return EFI_LOAD_ERROR;
  77
  78         while (relsz > 0) {
  79                 /* apply the relocs */
  80                 switch (ELF32_R_TYPE (rel->r_info)) {
  81                         case R_ARM_NONE:
  82                                 break;
  83
  84                         case R_ARM_RELATIVE:
  85                                 addr = (unsigned long *)
  86                                         (ldbase + rel->r_offset);
  87                                 *addr += ldbase;
  88                                 break;
  89
  90                         default:
  91                                 break;
  92                 }
  93                 rel = (Elf32_Rel*) ((char *) rel + relent);
  94                 relsz -= relent;
  95         }
  96         return EFI_SUCCESS;
  97 }