1 /* $NetBSD: gelf_sym.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_sym.c,v 1.5 2024/03/03 17:37:34 christos Exp $");
43 ELFTC_VCSID("Id: gelf_sym.c 3977 2022-05-01 06:45:34Z jkoshy");
44
45 GElf_Sym *
gelf_getsym(Elf_Data * ed,int ndx,GElf_Sym * dst)46 gelf_getsym(Elf_Data *ed, int ndx, GElf_Sym *dst)
47 {
48 int ec;
49 Elf *e;
50 size_t msz;
51 Elf_Scn *scn;
52 uint32_t sh_type;
53 Elf32_Sym *sym32;
54 Elf64_Sym *sym64;
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_SYM) {
75 LIBELF_SET_ERROR(ARGUMENT, 0);
76 return (NULL);
77 }
78
79 if ((msz = _libelf_msize(ELF_T_SYM, 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 sym32 = (Elf32_Sym *) d->d_data.d_buf + ndx;
91
92 dst->st_name = sym32->st_name;
93 dst->st_value = (Elf64_Addr) sym32->st_value;
94 dst->st_size = (Elf64_Xword) sym32->st_size;
95 dst->st_info = sym32->st_info;
96 dst->st_other = sym32->st_other;
97 dst->st_shndx = sym32->st_shndx;
98 } else {
99 sym64 = (Elf64_Sym *) d->d_data.d_buf + ndx;
100
101 *dst = *sym64;
102 }
103
104 return (dst);
105 }
106
107 int
gelf_update_sym(Elf_Data * ed,int ndx,GElf_Sym * gs)108 gelf_update_sym(Elf_Data *ed, int ndx, GElf_Sym *gs)
109 {
110 int ec;
111 Elf *e;
112 size_t msz;
113 Elf_Scn *scn;
114 uint32_t sh_type;
115 Elf32_Sym *sym32;
116 Elf64_Sym *sym64;
117 struct _Libelf_Data *d;
118
119 d = (struct _Libelf_Data *) ed;
120
121 if (d == NULL || ndx < 0 || gs == NULL ||
122 (scn = d->d_scn) == NULL ||
123 (e = scn->s_elf) == NULL) {
124 LIBELF_SET_ERROR(ARGUMENT, 0);
125 return (0);
126 }
127
128 ec = e->e_class;
129 assert(ec == ELFCLASS32 || ec == ELFCLASS64);
130
131 if (ec == ELFCLASS32)
132 sh_type = scn->s_shdr.s_shdr32.sh_type;
133 else
134 sh_type = scn->s_shdr.s_shdr64.sh_type;
135
136 if (_libelf_xlate_shtype(sh_type) != ELF_T_SYM) {
137 LIBELF_SET_ERROR(ARGUMENT, 0);
138 return (0);
139 }
140
141 if ((msz = _libelf_msize(ELF_T_SYM, ec, e->e_version)) == 0)
142 return (0);
143
144 assert(ndx >= 0);
145
146 if (msz * (size_t) ndx >= d->d_data.d_size) {
147 LIBELF_SET_ERROR(ARGUMENT, 0);
148 return (0);
149 }
150
151 if (ec == ELFCLASS32) {
152 sym32 = (Elf32_Sym *) d->d_data.d_buf + ndx;
153
154 sym32->st_name = gs->st_name;
155 sym32->st_info = gs->st_info;
156 sym32->st_other = gs->st_other;
157 sym32->st_shndx = gs->st_shndx;
158
159 LIBELF_COPY_U32(sym32, gs, st_value);
160 LIBELF_COPY_U32(sym32, gs, st_size);
161 } else {
162 sym64 = (Elf64_Sym *) d->d_data.d_buf + ndx;
163
164 *sym64 = *gs;
165 }
166
167 return (1);
168 }
169