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 <efi.h>
11 #include <elf.h>
12 
_relocate(long ldbase,Elf32_Dyn * dyn)13 efi_status_t EFIAPI _relocate(long ldbase, Elf32_Dyn *dyn)
14 {
15 	long relsz = 0, relent = 0;
16 	Elf32_Rel *rel = 0;
17 	unsigned long *addr;
18 	int i;
19 
20 	for (i = 0; dyn[i].d_tag != DT_NULL; ++i) {
21 		switch (dyn[i].d_tag) {
22 		case DT_REL:
23 			rel = (Elf32_Rel *)((unsigned long)dyn[i].d_un.d_ptr +
24 								ldbase);
25 			break;
26 
27 		case DT_RELSZ:
28 			relsz = dyn[i].d_un.d_val;
29 			break;
30 
31 		case DT_RELENT:
32 			relent = dyn[i].d_un.d_val;
33 			break;
34 
35 		case DT_RELA:
36 			break;
37 
38 		default:
39 			break;
40 		}
41 	}
42 
43 	if (!rel && relent == 0)
44 		return EFI_SUCCESS;
45 
46 	if (!rel || relent == 0)
47 		return EFI_LOAD_ERROR;
48 
49 	while (relsz > 0) {
50 		/* apply the relocs */
51 		switch (ELF32_R_TYPE(rel->r_info)) {
52 		case R_386_NONE:
53 			break;
54 
55 		case R_386_RELATIVE:
56 			addr = (unsigned long *)(ldbase + rel->r_offset);
57 			*addr += ldbase;
58 			break;
59 
60 		default:
61 			break;
62 		}
63 		rel = (Elf32_Rel *)((char *)rel + relent);
64 		relsz -= relent;
65 	}
66 
67 	return EFI_SUCCESS;
68 }
69