arch/x86/lib/reloc_ia32_efi.c

   1 // SPDX-License-Identifier: BSD-3-Clause
   2 /*
   3  * reloc_ia32.c - position independent x86 ELF shared object relocator
   4  * Copyright (C) 1999 Hewlett-Packard Co.
   5  * Contributed by David Mosberger <davidm@hpl.hp.com>.
   6  *
   7  * All rights reserved.
   8  */
   9
  10 #include <common.h>
  11 #include <efi.h>
  12 #include <elf.h>
  13
  14 efi_status_t EFIAPI _relocate(long ldbase, Elf32_Dyn *dyn)
  15 {
  16         long relsz = 0, relent = 0;
  17         Elf32_Rel *rel = 0;
  18         unsigned long *addr;
  19         int i;
  20
  21         for (i = 0; dyn[i].d_tag != DT_NULL; ++i) {
  22                 switch (dyn[i].d_tag) {
  23                 case DT_REL:
  24                         rel = (Elf32_Rel *)((unsigned long)dyn[i].d_un.d_ptr +
  25                                                                 ldbase);
  26                         break;
  27
  28                 case DT_RELSZ:
  29                         relsz = dyn[i].d_un.d_val;
  30                         break;
  31
  32                 case DT_RELENT:
  33                         relent = dyn[i].d_un.d_val;
  34                         break;
  35
  36                 case DT_RELA:
  37                         break;
  38
  39                 default:
  40                         break;
  41                 }
  42         }
  43
  44         if (!rel && relent == 0)
  45                 return EFI_SUCCESS;
  46
  47         if (!rel || relent == 0)
  48                 return EFI_LOAD_ERROR;
  49
  50         while (relsz > 0) {
  51                 /* apply the relocs */
  52                 switch (ELF32_R_TYPE(rel->r_info)) {
  53                 case R_386_NONE:
  54                         break;
  55
  56                 case R_386_RELATIVE:
  57                         addr = (unsigned long *)(ldbase + rel->r_offset);
  58                         *addr += ldbase;
  59                         break;
  60
  61                 default:
  62                         break;
  63                 }
  64                 rel = (Elf32_Rel *)((char *)rel + relent);
  65                 relsz -= relent;
  66         }
  67
  68         return EFI_SUCCESS;
  69 }