1 /* $NetBSD: gelf_sym.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_sym.c,v 1.2 2014/03/09 16:58:04 christos Exp $");
42 ELFTC_VCSID("Id: gelf_sym.c 2272 2011-12-03 17:07:31Z jkoshy ");
43
44 GElf_Sym *
gelf_getsym(Elf_Data * ed,int ndx,GElf_Sym * dst)45 gelf_getsym(Elf_Data *ed, int ndx, GElf_Sym *dst)
46 {
47 int ec;
48 Elf *e;
49 size_t msz;
50 Elf_Scn *scn;
51 uint32_t sh_type;
52 Elf32_Sym *sym32;
53 Elf64_Sym *sym64;
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_SYM) {
74 LIBELF_SET_ERROR(ARGUMENT, 0);
75 return (NULL);
76 }
77
78 msz = _libelf_msize(ELF_T_SYM, 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
89 sym32 = (Elf32_Sym *) d->d_data.d_buf + ndx;
90
91 dst->st_name = sym32->st_name;
92 dst->st_value = (Elf64_Addr) sym32->st_value;
93 dst->st_size = (Elf64_Xword) sym32->st_size;
94 dst->st_info = ELF64_ST_INFO(ELF32_ST_BIND(sym32->st_info),
95 ELF32_ST_TYPE(sym32->st_info));
96 dst->st_other = sym32->st_other;
97 dst->st_shndx = sym32->st_shndx;
98 } else {
99
100 sym64 = (Elf64_Sym *) d->d_data.d_buf + ndx;
101
102 *dst = *sym64;
103 }
104
105 return (dst);
106 }
107
108 int
gelf_update_sym(Elf_Data * ed,int ndx,GElf_Sym * gs)109 gelf_update_sym(Elf_Data *ed, int ndx, GElf_Sym *gs)
110 {
111 int ec;
112 Elf *e;
113 size_t msz;
114 Elf_Scn *scn;
115 uint32_t sh_type;
116 Elf32_Sym *sym32;
117 Elf64_Sym *sym64;
118 struct _Libelf_Data *d;
119
120 d = (struct _Libelf_Data *) ed;
121
122 if (d == NULL || ndx < 0 || gs == 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_SYM) {
138 LIBELF_SET_ERROR(ARGUMENT, 0);
139 return (0);
140 }
141
142 msz = _libelf_msize(ELF_T_SYM, ec, e->e_version);
143 assert(msz > 0);
144
145 if (msz * ndx >= d->d_data.d_size) {
146 LIBELF_SET_ERROR(ARGUMENT, 0);
147 return (0);
148 }
149
150 if (ec == ELFCLASS32) {
151 sym32 = (Elf32_Sym *) d->d_data.d_buf + ndx;
152
153 sym32->st_name = gs->st_name;
154 sym32->st_info = gs->st_info;
155 sym32->st_other = gs->st_other;
156 sym32->st_shndx = gs->st_shndx;
157
158 LIBELF_COPY_U32(sym32, gs, st_value);
159 LIBELF_COPY_U32(sym32, gs, st_size);
160 } else {
161 sym64 = (Elf64_Sym *) d->d_data.d_buf + ndx;
162
163 *sym64 = *gs;
164 }
165
166 return (1);
167 }
168