xref: /DragonStub/gnuefi/reloc_ia32.c (revision f412fd2a1a248b546b7085648dece8d908077fab)
1 /* reloc_ia32.c - position independent x86 ELF shared object relocator
2    Copyright (C) 1999 Hewlett-Packard Co.
3 	Contributed by David Mosberger <davidm@hpl.hp.com>.
4 
5     All rights reserved.
6 
7     Redistribution and use in source and binary forms, with or without
8     modification, are permitted provided that the following conditions
9     are met:
10 
11     * Redistributions of source code must retain the above copyright
12       notice, this list of conditions and the following disclaimer.
13     * Redistributions in binary form must reproduce the above
14       copyright notice, this list of conditions and the following
15       disclaimer in the documentation and/or other materials
16       provided with the distribution.
17     * Neither the name of Hewlett-Packard Co. nor the names of its
18       contributors may be used to endorse or promote products derived
19       from this software without specific prior written permission.
20 
21     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
22     CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
23     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
24     MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
25     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
26     BE LIABLE FOR ANYDIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
27     OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
28     PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
29     PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
30     THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
31     TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
32     THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33     SUCH DAMAGE.
34 */
35 
36 #include <efi.h>
37 #include <efilib.h>
38 
39 #include <elf.h>
40 
41 EFI_STATUS _relocate (long ldbase, Elf32_Dyn *dyn,
42 		      EFI_HANDLE image EFI_UNUSED,
43 		      EFI_SYSTEM_TABLE *systab EFI_UNUSED)
44 {
45 	long relsz = 0, relent = 0;
46 	Elf32_Rel *rel = 0;
47 	unsigned long *addr;
48 	int i;
49 
50 	for (i = 0; dyn[i].d_tag != DT_NULL; ++i) {
51 		switch (dyn[i].d_tag) {
52 			case DT_REL:
53 				rel = (Elf32_Rel*)
54 					((unsigned long)dyn[i].d_un.d_ptr
55 					 + ldbase);
56 				break;
57 
58 			case DT_RELSZ:
59 				relsz = dyn[i].d_un.d_val;
60 				break;
61 
62 			case DT_RELENT:
63 				relent = dyn[i].d_un.d_val;
64 				break;
65 
66 			case DT_RELA:
67 				break;
68 
69 			default:
70 				break;
71 		}
72 	}
73 
74         if (!rel && relent == 0)
75                 return EFI_SUCCESS;
76 
77 	if (!rel || relent == 0)
78 		return EFI_LOAD_ERROR;
79 
80 	while (relsz > 0) {
81 		/* apply the relocs */
82 		switch (ELF32_R_TYPE (rel->r_info)) {
83 			case R_386_NONE:
84 				break;
85 
86 			case R_386_RELATIVE:
87 				addr = (unsigned long *)
88 					(ldbase + rel->r_offset);
89 				*addr += ldbase;
90 				break;
91 
92 			default:
93 				break;
94 		}
95 		rel = (Elf32_Rel*) ((char *) rel + relent);
96 		relsz -= relent;
97 	}
98 	return EFI_SUCCESS;
99 }
100