xref: /netbsd-src/external/bsd/elftoolchain/dist/libelf/gelf_symshndx.c (revision 5ac3bc719ce6e70593039505b491894133237d12)
1 /*	$NetBSD: gelf_symshndx.c,v 1.5 2024/03/03 17:37:34 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 2006,2008,2020 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 
38 #include "_libelf.h"
39 
40 __RCSID("$NetBSD: gelf_symshndx.c,v 1.5 2024/03/03 17:37:34 christos Exp $");
41 ELFTC_VCSID("Id: gelf_symshndx.c 3977 2022-05-01 06:45:34Z jkoshy");
42 
43 GElf_Sym *
gelf_getsymshndx(Elf_Data * d,Elf_Data * id,int ndx,GElf_Sym * dst,Elf32_Word * shindex)44 gelf_getsymshndx(Elf_Data *d, Elf_Data *id, int ndx, GElf_Sym *dst,
45     Elf32_Word *shindex)
46 {
47 	int ec;
48 	Elf *e;
49 	size_t msz;
50 	Elf_Scn *scn;
51 	uint32_t sh_type;
52 	struct _Libelf_Data *ld, *lid;
53 
54 	ld = (struct _Libelf_Data *) d;
55 	lid = (struct _Libelf_Data *) id;
56 
57 	if (gelf_getsym(d, ndx, dst) == 0)
58 		return (NULL);
59 
60 	if (shindex == NULL)
61 		return (dst);
62 
63 	if (lid == NULL) {
64 		*shindex = 0;
65 		return (dst);
66 	}
67 
68 	if ((scn = lid->d_scn) == NULL ||
69 	    (e = scn->s_elf) == NULL || (e != ld->d_scn->s_elf)) {
70 		LIBELF_SET_ERROR(ARGUMENT, 0);
71 		return (NULL);
72 	}
73 
74 	ec = e->e_class;
75 	assert(ec == ELFCLASS32 || ec == ELFCLASS64);
76 
77 	if (ec == ELFCLASS32)
78 		sh_type = scn->s_shdr.s_shdr32.sh_type;
79 	else
80 		sh_type = scn->s_shdr.s_shdr64.sh_type;
81 
82 	if (_libelf_xlate_shtype(sh_type) != ELF_T_WORD ||
83 	   id->d_type != ELF_T_WORD) {
84 		LIBELF_SET_ERROR(ARGUMENT, 0);
85 		return (NULL);
86 	}
87 
88 	if ((msz = _libelf_msize(ELF_T_WORD, ec, e->e_version)) == 0)
89 		return (NULL);
90 
91 	assert(ndx >= 0);
92 
93 	if (msz * (size_t) ndx >= id->d_size) {
94 		LIBELF_SET_ERROR(ARGUMENT, 0);
95 		return (NULL);
96 	}
97 
98 	*shindex = ((Elf32_Word *) id->d_buf)[ndx];
99 
100 	return (dst);
101 }
102 
103 int
gelf_update_symshndx(Elf_Data * d,Elf_Data * id,int ndx,GElf_Sym * gs,Elf32_Word xindex)104 gelf_update_symshndx(Elf_Data *d, Elf_Data *id, int ndx, GElf_Sym *gs,
105     Elf32_Word xindex)
106 {
107 	int ec;
108 	Elf *e;
109 	size_t msz;
110 	Elf_Scn *scn;
111 	uint32_t sh_type;
112 	struct _Libelf_Data *ld, *lid;
113 
114 	ld = (struct _Libelf_Data *) d;
115 	lid = (struct _Libelf_Data *) id;
116 
117 	if (gelf_update_sym(d, ndx, gs) == 0)
118 		return (0);
119 
120 	if (lid == NULL || (scn = lid->d_scn) == NULL ||
121 	    (e = scn->s_elf) == NULL || (e != ld->d_scn->s_elf)) {
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_WORD ||
135 	    d->d_type != ELF_T_WORD) {
136 		LIBELF_SET_ERROR(ARGUMENT, 0);
137 		return (0);
138 	}
139 
140 	if ((msz = _libelf_msize(ELF_T_WORD, ec, e->e_version)) == 0)
141 		return (0);
142 
143 	assert(ndx >= 0);
144 
145 	if (msz * (size_t) ndx >= id->d_size) {
146 		LIBELF_SET_ERROR(ARGUMENT, 0);
147 		return (0);
148 	}
149 
150 	*(((Elf32_Word *) id->d_buf) + ndx) = xindex;
151 
152 	return (1);
153 }
154