1 /* $NetBSD: gelf_rela.c,v 1.5 2024/03/03 17:37:34 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 #include <stdint.h>
39
40 #include "_libelf.h"
41
42 __RCSID("$NetBSD: gelf_rela.c,v 1.5 2024/03/03 17:37:34 christos Exp $");
43 ELFTC_VCSID("Id: gelf_rela.c 3977 2022-05-01 06:45:34Z jkoshy");
44
45 GElf_Rela *
gelf_getrela(Elf_Data * ed,int ndx,GElf_Rela * dst)46 gelf_getrela(Elf_Data *ed, int ndx, GElf_Rela *dst)
47 {
48 int ec;
49 Elf *e;
50 size_t msz;
51 Elf_Scn *scn;
52 uint32_t sh_type;
53 Elf32_Rela *rela32;
54 Elf64_Rela *rela64;
55 struct _Libelf_Data *d;
56
57 d = (struct _Libelf_Data *) ed;
58
59 if (d == NULL || ndx < 0 || dst == NULL ||
60 (scn = d->d_scn) == NULL ||
61 (e = scn->s_elf) == NULL) {
62 LIBELF_SET_ERROR(ARGUMENT, 0);
63 return (NULL);
64 }
65
66 ec = e->e_class;
67 assert(ec == ELFCLASS32 || ec == ELFCLASS64);
68
69 if (ec == ELFCLASS32)
70 sh_type = scn->s_shdr.s_shdr32.sh_type;
71 else
72 sh_type = scn->s_shdr.s_shdr64.sh_type;
73
74 if (_libelf_xlate_shtype(sh_type) != ELF_T_RELA) {
75 LIBELF_SET_ERROR(ARGUMENT, 0);
76 return (NULL);
77 }
78
79 if ((msz = _libelf_msize(ELF_T_RELA, ec, e->e_version)) == 0)
80 return (NULL);
81
82 assert(ndx >= 0);
83
84 if (msz * (size_t) ndx >= d->d_data.d_size) {
85 LIBELF_SET_ERROR(ARGUMENT, 0);
86 return (NULL);
87 }
88
89 if (ec == ELFCLASS32) {
90 rela32 = (Elf32_Rela *) d->d_data.d_buf + ndx;
91
92 dst->r_offset = (Elf64_Addr) rela32->r_offset;
93 dst->r_info = ELF64_R_INFO(
94 (Elf64_Xword) ELF32_R_SYM(rela32->r_info),
95 ELF32_R_TYPE(rela32->r_info));
96 dst->r_addend = (Elf64_Sxword) rela32->r_addend;
97
98 } else {
99
100 rela64 = (Elf64_Rela *) d->d_data.d_buf + ndx;
101
102 *dst = *rela64;
103 }
104
105 return (dst);
106 }
107
108 int
gelf_update_rela(Elf_Data * ed,int ndx,GElf_Rela * dr)109 gelf_update_rela(Elf_Data *ed, int ndx, GElf_Rela *dr)
110 {
111 int ec;
112 Elf *e;
113 size_t msz;
114 Elf_Scn *scn;
115 uint32_t sh_type;
116 Elf32_Rela *rela32;
117 Elf64_Rela *rela64;
118 struct _Libelf_Data *d;
119
120 d = (struct _Libelf_Data *) ed;
121
122 if (d == NULL || ndx < 0 || dr == NULL ||
123 (scn = d->d_scn) == NULL ||
124 (e = scn->s_elf) == NULL) {
125 LIBELF_SET_ERROR(ARGUMENT, 0);
126 return (0);
127 }
128
129 ec = e->e_class;
130 assert(ec == ELFCLASS32 || ec == ELFCLASS64);
131
132 if (ec == ELFCLASS32)
133 sh_type = scn->s_shdr.s_shdr32.sh_type;
134 else
135 sh_type = scn->s_shdr.s_shdr64.sh_type;
136
137 if (_libelf_xlate_shtype(sh_type) != ELF_T_RELA) {
138 LIBELF_SET_ERROR(ARGUMENT, 0);
139 return (0);
140 }
141
142 if ((msz = _libelf_msize(ELF_T_RELA, ec, e->e_version)) == 0)
143 return (0);
144
145 assert(ndx >= 0);
146
147 if (msz * (size_t) ndx >= d->d_data.d_size) {
148 LIBELF_SET_ERROR(ARGUMENT, 0);
149 return (0);
150 }
151
152 if (ec == ELFCLASS32) {
153 rela32 = (Elf32_Rela *) d->d_data.d_buf + ndx;
154
155 LIBELF_COPY_U32(rela32, dr, r_offset);
156
157 if (ELF64_R_SYM(dr->r_info) > ELF32_R_SYM(~0U) ||
158 ELF64_R_TYPE(dr->r_info) > ELF32_R_TYPE(~0U)) {
159 LIBELF_SET_ERROR(RANGE, 0);
160 return (0);
161 }
162 rela32->r_info = ELF32_R_INFO(
163 (Elf32_Word) ELF64_R_SYM(dr->r_info),
164 (Elf32_Word) ELF64_R_TYPE(dr->r_info));
165
166 LIBELF_COPY_S32(rela32, dr, r_addend);
167 } else {
168 rela64 = (Elf64_Rela *) d->d_data.d_buf + ndx;
169
170 *rela64 = *dr;
171 }
172
173 return (1);
174 }
175