1/*-
2 * Copyright (c) 2006,2008 Joseph Koshy
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <assert.h>
28#include <gelf.h>
29
30#include "_libelf.h"
31
32ELFTC_VCSID("$Id: gelf_symshndx.c 3732 2019-04-22 11:08:38Z jkoshy $");
33
34GElf_Sym *
35gelf_getsymshndx(Elf_Data *d, Elf_Data *id, int ndx, GElf_Sym *dst,
36    Elf32_Word *shindex)
37{
38	int ec;
39	Elf *e;
40	size_t msz;
41	Elf_Scn *scn;
42	uint32_t sh_type;
43	struct _Libelf_Data *ld, *lid;
44
45	ld = (struct _Libelf_Data *) d;
46	lid = (struct _Libelf_Data *) id;
47
48	if (gelf_getsym(d, ndx, dst) == 0)
49		return (NULL);
50
51	if (lid == NULL || (scn = lid->d_scn) == NULL ||
52	    (e = scn->s_elf) == NULL || (e != ld->d_scn->s_elf) ||
53	    shindex == NULL) {
54		LIBELF_SET_ERROR(ARGUMENT, 0);
55		return (NULL);
56	}
57
58	ec = e->e_class;
59	assert(ec == ELFCLASS32 || ec == ELFCLASS64);
60
61	if (ec == ELFCLASS32)
62		sh_type = scn->s_shdr.s_shdr32.sh_type;
63	else
64		sh_type = scn->s_shdr.s_shdr64.sh_type;
65
66	if (_libelf_xlate_shtype(sh_type) != ELF_T_WORD ||
67	   id->d_type != ELF_T_WORD) {
68		LIBELF_SET_ERROR(ARGUMENT, 0);
69		return (NULL);
70	}
71
72	if ((msz = _libelf_msize(ELF_T_WORD, ec, e->e_version)) == 0)
73		return (NULL);
74
75	assert(ndx >= 0);
76
77	if (msz * (size_t) ndx >= id->d_size) {
78		LIBELF_SET_ERROR(ARGUMENT, 0);
79		return (NULL);
80	}
81
82	*shindex = ((Elf32_Word *) id->d_buf)[ndx];
83
84	return (dst);
85}
86
87int
88gelf_update_symshndx(Elf_Data *d, Elf_Data *id, int ndx, GElf_Sym *gs,
89    Elf32_Word xindex)
90{
91	int ec;
92	Elf *e;
93	size_t msz;
94	Elf_Scn *scn;
95	uint32_t sh_type;
96	struct _Libelf_Data *ld, *lid;
97
98	ld = (struct _Libelf_Data *) d;
99	lid = (struct _Libelf_Data *) id;
100
101	if (gelf_update_sym(d, ndx, gs) == 0)
102		return (0);
103
104	if (lid == NULL || (scn = lid->d_scn) == NULL ||
105	    (e = scn->s_elf) == NULL || (e != ld->d_scn->s_elf)) {
106		LIBELF_SET_ERROR(ARGUMENT, 0);
107		return (0);
108	}
109
110	ec = e->e_class;
111	assert(ec == ELFCLASS32 || ec == ELFCLASS64);
112
113	if (ec == ELFCLASS32)
114		sh_type = scn->s_shdr.s_shdr32.sh_type;
115	else
116		sh_type = scn->s_shdr.s_shdr64.sh_type;
117
118	if (_libelf_xlate_shtype(sh_type) != ELF_T_WORD ||
119	    d->d_type != ELF_T_WORD) {
120		LIBELF_SET_ERROR(ARGUMENT, 0);
121		return (0);
122	}
123
124	if ((msz = _libelf_msize(ELF_T_WORD, ec, e->e_version)) == 0)
125		return (0);
126
127	assert(ndx >= 0);
128
129	if (msz * (size_t) ndx >= id->d_size) {
130		LIBELF_SET_ERROR(ARGUMENT, 0);
131		return (0);
132	}
133
134	*(((Elf32_Word *) id->d_buf) + ndx) = xindex;
135
136	return (1);
137}
138