1 // SPDX-License-Identifier: BSD-3-Clause 2 /* 3 * reloc_x86_64.c - position independent x86_64 ELF shared object relocator 4 * Copyright (C) 1999 Hewlett-Packard Co. 5 * Contributed by David Mosberger <davidm@hpl.hp.com>. 6 * Copyright (C) 2005 Intel Co. 7 * Contributed by Fenghua Yu <fenghua.yu@intel.com>. 8 * 9 * All rights reserved. 10 */ 11 12 #include <common.h> 13 #include <efi.h> 14 #include <elf.h> 15 16 efi_status_t EFIAPI _relocate(long ldbase, Elf64_Dyn *dyn) 17 { 18 long relsz = 0, relent = 0; 19 Elf64_Rel *rel = 0; 20 unsigned long *addr; 21 int i; 22 23 for (i = 0; dyn[i].d_tag != DT_NULL; ++i) { 24 switch (dyn[i].d_tag) { 25 case DT_RELA: 26 rel = (Elf64_Rel *) 27 ((unsigned long)dyn[i].d_un.d_ptr + ldbase); 28 break; 29 case DT_RELASZ: 30 relsz = dyn[i].d_un.d_val; 31 break; 32 case DT_RELAENT: 33 relent = dyn[i].d_un.d_val; 34 break; 35 default: 36 break; 37 } 38 } 39 40 if (!rel && relent == 0) 41 return EFI_SUCCESS; 42 43 if (!rel || relent == 0) 44 return EFI_LOAD_ERROR; 45 46 while (relsz > 0) { 47 /* apply the relocs */ 48 switch (ELF64_R_TYPE(rel->r_info)) { 49 case R_X86_64_NONE: 50 break; 51 case R_X86_64_RELATIVE: 52 addr = (unsigned long *)(ldbase + rel->r_offset); 53 *addr += ldbase; 54 break; 55 default: 56 break; 57 } 58 rel = (Elf64_Rel *)((char *)rel + relent); 59 relsz -= relent; 60 } 61 62 return EFI_SUCCESS; 63 } 64