grub-core/efiemu/i386/loadcore64.c

   1 /* i386 CPU-specific part of loadcore.c for 32-bit mode */
   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/err.h>
  21 #include <grub/mm.h>
  22 #include <grub/misc.h>
  23 #include <grub/efiemu/efiemu.h>
  24 #include <grub/cpu/efiemu.h>
  25 #include <grub/elf.h>
  26 #include <grub/i18n.h>
  27
  28 /* Check if EHDR is a valid ELF header.  */
  29 int
  30 grub_arch_efiemu_check_header64 (void *ehdr)
  31 {
  32   Elf64_Ehdr *e = ehdr;
  33
  34   return (e->e_ident[EI_CLASS] == ELFCLASS64
  35           && e->e_ident[EI_DATA] == ELFDATA2LSB
  36           && e->e_machine == EM_X86_64);
  37 }
  38
  39 /* Relocate symbols.  */
  40 grub_err_t
  41 grub_arch_efiemu_relocate_symbols64 (grub_efiemu_segment_t segs,
  42                                      struct grub_efiemu_elf_sym *elfsyms,
  43                                      void *ehdr)
  44 {
  45   unsigned i;
  46   Elf64_Ehdr *e = ehdr;
  47   Elf64_Shdr *s;
  48   grub_err_t err;
  49
  50   for (i = 0, s = (Elf64_Shdr *) ((char *) e + e->e_shoff);
  51        i < e->e_shnum;
  52        i++, s = (Elf64_Shdr *) ((char *) s + e->e_shentsize))
  53     if (s->sh_type == SHT_RELA)
  54       {
  55         grub_efiemu_segment_t seg;
  56         grub_dprintf ("efiemu", "shtrel\n");
  57
  58         /* Find the target segment.  */
  59         for (seg = segs; seg; seg = seg->next)
  60           if (seg->section == s->sh_info)
  61             break;
  62
  63         if (seg)
  64           {
  65             Elf64_Rela *rel, *max;
  66
  67             for (rel = (Elf64_Rela *) ((char *) e + s->sh_offset),
  68                    max = rel + (unsigned long) s->sh_size
  69                    / (unsigned long)s->sh_entsize;
  70                  rel < max;
  71                  rel++)
  72               {
  73                 void *addr;
  74                 grub_uint32_t *addr32;
  75                 grub_uint64_t *addr64;
  76                 struct grub_efiemu_elf_sym sym;
  77                 if (seg->size < rel->r_offset)
  78                   return grub_error (GRUB_ERR_BAD_MODULE,
  79                                      "reloc offset is out of the segment");
  80
  81                 addr =
  82                   ((char *) grub_efiemu_mm_obtain_request (seg->handle)
  83                    + seg->off + rel->r_offset);
  84                 addr32 = (grub_uint32_t *) addr;
  85                 addr64 = (grub_uint64_t *) addr;
  86                 sym = elfsyms[ELF64_R_SYM (rel->r_info)];
  87
  88                 switch (ELF64_R_TYPE (rel->r_info))
  89                   {
  90                   case R_X86_64_64:
  91                     err = grub_efiemu_write_value (addr,
  92                                                    *addr64 + rel->r_addend
  93                                                    + sym.off, sym.handle,
  94                                                    0, seg->ptv_rel_needed,
  95                                                    sizeof (grub_uint64_t));
  96                     if (err)
  97                       return err;
  98                     break;
  99
 100                   case R_X86_64_PC32:
 101                     err = grub_efiemu_write_value (addr,
 102                                                    *addr32 + rel->r_addend
 103                                                    + sym.off
 104                                                    - rel->r_offset - seg->off,
 105                                                    sym.handle, seg->handle,
 106                                                    seg->ptv_rel_needed,
 107                                                    sizeof (grub_uint32_t));
 108                     if (err)
 109                       return err;
 110                     break;
 111
 112                   case R_X86_64_32:
 113                   case R_X86_64_32S:
 114                     err = grub_efiemu_write_value (addr,
 115                                                    *addr32 + rel->r_addend
 116                                                    + sym.off, sym.handle,
 117                                                    0, seg->ptv_rel_needed,
 118                                                    sizeof (grub_uint32_t));
 119                     if (err)
 120                       return err;
 121                     break;
 122                   default:
 123                     return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET,
 124                                        N_("relocation 0x%x is not implemented yet"),
 125                                        ELF_R_TYPE (rel->r_info));
 126                   }
 127               }
 128           }
 129       }
 130
 131   return GRUB_ERR_NONE;
 132 }