1 /* $NetBSD: gelf_rel.c,v 1.2 2014/03/09 16:58:04 christos Exp $ */
2
3 /*-
4 * Copyright (c) 2006,2008 Joseph Koshy
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 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #if HAVE_NBTOOL_CONFIG_H
30 # include "nbtool_config.h"
31 #endif
32
33 #include <sys/cdefs.h>
34
35 #include <assert.h>
36 #include <gelf.h>
37 #include <limits.h>
38
39 #include "_libelf.h"
40
41 __RCSID("$NetBSD: gelf_rel.c,v 1.2 2014/03/09 16:58:04 christos Exp $");
42 ELFTC_VCSID("Id: gelf_rel.c 2272 2011-12-03 17:07:31Z jkoshy ");
43
44 GElf_Rel *
gelf_getrel(Elf_Data * ed,int ndx,GElf_Rel * dst)45 gelf_getrel(Elf_Data *ed, int ndx, GElf_Rel *dst)
46 {
47 int ec;
48 Elf *e;
49 size_t msz;
50 Elf_Scn *scn;
51 uint32_t sh_type;
52 Elf32_Rel *rel32;
53 Elf64_Rel *rel64;
54 struct _Libelf_Data *d;
55
56 d = (struct _Libelf_Data *) ed;
57
58 if (d == NULL || ndx < 0 || dst == NULL ||
59 (scn = d->d_scn) == NULL ||
60 (e = scn->s_elf) == NULL) {
61 LIBELF_SET_ERROR(ARGUMENT, 0);
62 return (NULL);
63 }
64
65 ec = e->e_class;
66 assert(ec == ELFCLASS32 || ec == ELFCLASS64);
67
68 if (ec == ELFCLASS32)
69 sh_type = scn->s_shdr.s_shdr32.sh_type;
70 else
71 sh_type = scn->s_shdr.s_shdr64.sh_type;
72
73 if (_libelf_xlate_shtype(sh_type) != ELF_T_REL) {
74 LIBELF_SET_ERROR(ARGUMENT, 0);
75 return (NULL);
76 }
77
78 msz = _libelf_msize(ELF_T_REL, ec, e->e_version);
79
80 assert(msz > 0);
81
82 if (msz * ndx >= d->d_data.d_size) {
83 LIBELF_SET_ERROR(ARGUMENT, 0);
84 return (NULL);
85 }
86
87 if (ec == ELFCLASS32) {
88 rel32 = (Elf32_Rel *) d->d_data.d_buf + ndx;
89
90 dst->r_offset = (Elf64_Addr) rel32->r_offset;
91 dst->r_info = ELF64_R_INFO(
92 (Elf64_Xword) ELF32_R_SYM(rel32->r_info),
93 ELF32_R_TYPE(rel32->r_info));
94
95 } else {
96
97 rel64 = (Elf64_Rel *) d->d_data.d_buf + ndx;
98
99 *dst = *rel64;
100 }
101
102 return (dst);
103 }
104
105 int
gelf_update_rel(Elf_Data * ed,int ndx,GElf_Rel * dr)106 gelf_update_rel(Elf_Data *ed, int ndx, GElf_Rel *dr)
107 {
108 int ec;
109 Elf *e;
110 size_t msz;
111 Elf_Scn *scn;
112 uint32_t sh_type;
113 Elf32_Rel *rel32;
114 Elf64_Rel *rel64;
115 struct _Libelf_Data *d;
116
117 d = (struct _Libelf_Data *) ed;
118
119 if (d == NULL || ndx < 0 || dr == NULL ||
120 (scn = d->d_scn) == NULL ||
121 (e = scn->s_elf) == NULL) {
122 LIBELF_SET_ERROR(ARGUMENT, 0);
123 return (0);
124 }
125
126 ec = e->e_class;
127 assert(ec == ELFCLASS32 || ec == ELFCLASS64);
128
129 if (ec == ELFCLASS32)
130 sh_type = scn->s_shdr.s_shdr32.sh_type;
131 else
132 sh_type = scn->s_shdr.s_shdr64.sh_type;
133
134 if (_libelf_xlate_shtype(sh_type) != ELF_T_REL) {
135 LIBELF_SET_ERROR(ARGUMENT, 0);
136 return (0);
137 }
138
139 msz = _libelf_msize(ELF_T_REL, ec, e->e_version);
140 assert(msz > 0);
141
142 if (msz * ndx >= d->d_data.d_size) {
143 LIBELF_SET_ERROR(ARGUMENT, 0);
144 return (0);
145 }
146
147 if (ec == ELFCLASS32) {
148 rel32 = (Elf32_Rel *) d->d_data.d_buf + ndx;
149
150 LIBELF_COPY_U32(rel32, dr, r_offset);
151
152 if (ELF64_R_SYM(dr->r_info) > ELF32_R_SYM(~0UL) ||
153 ELF64_R_TYPE(dr->r_info) > ELF32_R_TYPE(~0U)) {
154 LIBELF_SET_ERROR(RANGE, 0);
155 return (0);
156 }
157 rel32->r_info = ELF32_R_INFO(ELF64_R_SYM(dr->r_info),
158 ELF64_R_TYPE(dr->r_info));
159 } else {
160 rel64 = (Elf64_Rel *) d->d_data.d_buf + ndx;
161
162 *rel64 = *dr;
163 }
164
165 return (1);
166 }
167