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 
_relocate(long ldbase,Elf32_Dyn * dyn)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 }
70