1 /*-
2  * Copyright (c) 2006 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 <sys/cdefs.h>
28 __FBSDID("$FreeBSD: stable/10/lib/libelf/gelf_symshndx.c 164190 2006-11-11 17:16:35Z jkoshy $");
29 
30 #include <sys/limits.h>
31 
32 #include <assert.h>
33 #include <gelf.h>
34 
35 #include "_libelf.h"
36 
37 GElf_Sym *
gelf_getsymshndx(Elf_Data * d,Elf_Data * id,int ndx,GElf_Sym * dst,Elf32_Word * shindex)38 gelf_getsymshndx(Elf_Data *d, Elf_Data *id, int ndx, GElf_Sym *dst,
39     Elf32_Word *shindex)
40 {
41 	int ec;
42 	Elf *e;
43 	Elf_Scn *scn;
44 	size_t msz;
45 	uint32_t sh_type;
46 
47 	if (gelf_getsym(d, ndx, dst) == 0)
48 		return (NULL);
49 
50 	if (id == NULL || (scn = id->d_scn) == NULL ||
51 	    (e = scn->s_elf) == NULL || (e != d->d_scn->s_elf) ||
52 	    shindex == NULL) {
53 		LIBELF_SET_ERROR(ARGUMENT, 0);
54 		return (NULL);
55 	}
56 
57 	ec = e->e_class;
58 	assert(ec == ELFCLASS32 || ec == ELFCLASS64);
59 
60 	if (ec == ELFCLASS32)
61 		sh_type = scn->s_shdr.s_shdr32.sh_type;
62 	else
63 		sh_type = scn->s_shdr.s_shdr64.sh_type;
64 
65 	if (_libelf_xlate_shtype(sh_type) != ELF_T_WORD ||
66 	   id->d_type != ELF_T_WORD) {
67 		LIBELF_SET_ERROR(ARGUMENT, 0);
68 		return (NULL);
69 	}
70 
71 	msz = _libelf_msize(ELF_T_WORD, ec, e->e_version);
72 
73 	assert(msz > 0);
74 
75 	if (msz * ndx >= id->d_size) {
76 		LIBELF_SET_ERROR(ARGUMENT, 0);
77 		return (NULL);
78 	}
79 
80 	*shindex = ((Elf32_Word *) id->d_buf)[ndx];
81 
82 	return (dst);
83 }
84 
85 int
gelf_update_symshndx(Elf_Data * d,Elf_Data * id,int ndx,GElf_Sym * gs,Elf32_Word xindex)86 gelf_update_symshndx(Elf_Data *d, Elf_Data *id, int ndx, GElf_Sym *gs,
87     Elf32_Word xindex)
88 {
89 	int ec;
90 	Elf *e;
91 	Elf_Scn *scn;
92 	size_t msz;
93 	uint32_t sh_type;
94 
95 	if (gelf_update_sym(d, ndx, gs) == 0)
96 		return (0);
97 
98 	if (id == NULL || (scn = id->d_scn) == NULL ||
99 	    (e = scn->s_elf) == NULL || (e != d->d_scn->s_elf)) {
100 		LIBELF_SET_ERROR(ARGUMENT, 0);
101 		return (0);
102 	}
103 
104 	ec = e->e_class;
105 	assert(ec == ELFCLASS32 || ec == ELFCLASS64);
106 
107 	if (ec == ELFCLASS32)
108 		sh_type = scn->s_shdr.s_shdr32.sh_type;
109 	else
110 		sh_type = scn->s_shdr.s_shdr64.sh_type;
111 
112 	if (_libelf_xlate_shtype(sh_type) != ELF_T_WORD ||
113 	    d->d_type != ELF_T_WORD) {
114 		LIBELF_SET_ERROR(ARGUMENT, 0);
115 		return (0);
116 	}
117 
118 	msz = _libelf_msize(ELF_T_WORD, ec, e->e_version);
119 	assert(msz > 0);
120 
121 	if (msz * ndx >= id->d_size) {
122 		LIBELF_SET_ERROR(ARGUMENT, 0);
123 		return (0);
124 	}
125 
126 	*(((Elf32_Word *) id->d_buf) + ndx) = xindex;
127 
128 	return (1);
129 }
130