122 lines
		
	
	
	
		
			3.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			122 lines
		
	
	
	
		
			3.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* dl-x86_64.c - arch-dependent part of loadable module support */
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| /*
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|  *  GRUB  --  GRand Unified Bootloader
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|  *  Copyright (C) 2002,2005,2007,2009  Free Software Foundation, Inc.
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|  *
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|  *  GRUB is free software: you can redistribute it and/or modify
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|  *  it under the terms of the GNU General Public License as published by
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|  *  the Free Software Foundation, either version 3 of the License, or
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|  *  (at your option) any later version.
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|  *
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|  *  GRUB is distributed in the hope that it will be useful,
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|  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
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|  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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|  *  GNU General Public License for more details.
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|  *
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|  *  You should have received a copy of the GNU General Public License
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|  *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
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|  */
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| 
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| #include <grub/dl.h>
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| #include <grub/elf.h>
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| #include <grub/misc.h>
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| #include <grub/err.h>
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| #include <grub/i18n.h>
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| 
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| /* Check if EHDR is a valid ELF header.  */
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| grub_err_t
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| grub_arch_dl_check_header (void *ehdr)
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| {
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|   Elf64_Ehdr *e = ehdr;
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| 
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|   /* Check the magic numbers.  */
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|   if (e->e_ident[EI_CLASS] != ELFCLASS64
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|       || e->e_ident[EI_DATA] != ELFDATA2LSB
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|       || e->e_machine != EM_X86_64)
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|     return grub_error (GRUB_ERR_BAD_OS, N_("invalid arch-dependent ELF magic"));
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| 
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|   return GRUB_ERR_NONE;
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| }
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| 
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| /* Relocate symbols.  */
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| grub_err_t
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| grub_arch_dl_relocate_symbols (grub_dl_t mod, void *ehdr)
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| {
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|   Elf64_Ehdr *e = ehdr;
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|   Elf64_Shdr *s;
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|   Elf64_Word entsize;
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|   unsigned i;
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| 
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|   /* Find a symbol table.  */
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|   for (i = 0, s = (Elf64_Shdr *) ((char *) e + e->e_shoff);
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|        i < e->e_shnum;
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|        i++, s = (Elf64_Shdr *) ((char *) s + e->e_shentsize))
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|     if (s->sh_type == SHT_SYMTAB)
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|       break;
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| 
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|   if (i == e->e_shnum)
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|     return grub_error (GRUB_ERR_BAD_MODULE, N_("no symbol table"));
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| 
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|   entsize = s->sh_entsize;
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| 
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|   for (i = 0, s = (Elf64_Shdr *) ((char *) e + e->e_shoff);
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|        i < e->e_shnum;
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|        i++, s = (Elf64_Shdr *) ((char *) s + e->e_shentsize))
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|     if (s->sh_type == SHT_RELA)
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|       {
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| 	grub_dl_segment_t seg;
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| 
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| 	/* Find the target segment.  */
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| 	for (seg = mod->segment; seg; seg = seg->next)
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| 	  if (seg->section == s->sh_info)
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| 	    break;
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| 
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| 	if (seg)
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| 	  {
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| 	    Elf64_Rela *rel, *max;
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| 
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| 	    for (rel = (Elf64_Rela *) ((char *) e + s->sh_offset),
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| 		   max = rel + s->sh_size / s->sh_entsize;
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| 		 rel < max;
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| 		 rel++)
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| 	      {
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| 		Elf64_Word *addr32;
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| 		Elf64_Xword *addr64;
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| 		Elf64_Sym *sym;
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| 
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| 		if (seg->size < rel->r_offset)
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| 		  return grub_error (GRUB_ERR_BAD_MODULE,
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| 				     "reloc offset is out of the segment");
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| 
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| 		addr32 = (Elf64_Word *) ((char *) seg->addr + rel->r_offset);
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| 		addr64 = (Elf64_Xword *) addr32;
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| 		sym = (Elf64_Sym *) ((char *) mod->symtab
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| 				     + entsize * ELF_R_SYM (rel->r_info));
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| 
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| 		switch (ELF_R_TYPE (rel->r_info))
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| 		  {
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| 		  case R_X86_64_64:
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| 		    *addr64 += rel->r_addend + sym->st_value;
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| 		    break;
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| 
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| 		  case R_X86_64_PC32:
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| 		    *addr32 += rel->r_addend + sym->st_value -
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| 		              (Elf64_Xword) seg->addr - rel->r_offset;
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| 		    break;
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| 
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|                   case R_X86_64_32:
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|                   case R_X86_64_32S:
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|                     *addr32 += rel->r_addend + sym->st_value;
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|                     break;
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| 
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| 		  default:
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| 		    return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET,
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| 				       N_("relocation 0x%x is not implemented yet"),
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| 				       ELF_R_TYPE (rel->r_info));
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| 		  }
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| 	      }
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| 	  }
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|       }
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| 
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|   return GRUB_ERR_NONE;
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| }
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