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 #include <libelf.h>
30 #include <limits.h>
31 #include <stdint.h>
32 
33 #include "_libelf.h"
34 
35 ELFTC_VCSID("$Id: gelf_shdr.c 3177 2015-03-30 18:19:41Z emaste $");
36 
37 Elf32_Shdr *
38 elf32_getshdr(Elf_Scn *s)
39 {
40 	return (_libelf_getshdr(s, ELFCLASS32));
41 }
42 
43 Elf64_Shdr *
44 elf64_getshdr(Elf_Scn *s)
45 {
46 	return (_libelf_getshdr(s, ELFCLASS64));
47 }
48 
49 GElf_Shdr *
50 gelf_getshdr(Elf_Scn *s, GElf_Shdr *d)
51 {
52 	int ec;
53 	void *sh;
54 	Elf32_Shdr *sh32;
55 	Elf64_Shdr *sh64;
56 
57 	if (d == NULL) {
58 		LIBELF_SET_ERROR(ARGUMENT, 0);
59 		return (NULL);
60 	}
61 
62 	if ((sh = _libelf_getshdr(s, ELFCLASSNONE)) == NULL)
63 		return (NULL);
64 
65 	ec = s->s_elf->e_class;
66 	assert(ec == ELFCLASS32 || ec == ELFCLASS64);
67 
68 	if (ec == ELFCLASS32) {
69 		sh32 = (Elf32_Shdr *) sh;
70 
71 		d->sh_name      = sh32->sh_name;
72 		d->sh_type      = sh32->sh_type;
73 		d->sh_flags     = (Elf64_Xword) sh32->sh_flags;
74 		d->sh_addr      = (Elf64_Addr) sh32->sh_addr;
75 		d->sh_offset    = (Elf64_Off) sh32->sh_offset;
76 		d->sh_size      = (Elf64_Xword) sh32->sh_size;
77 		d->sh_link      = sh32->sh_link;
78 		d->sh_info      = sh32->sh_info;
79 		d->sh_addralign = (Elf64_Xword) sh32->sh_addralign;
80 		d->sh_entsize   = (Elf64_Xword) sh32->sh_entsize;
81 	} else {
82 		sh64 = (Elf64_Shdr *) sh;
83 		*d = *sh64;
84 	}
85 
86 	return (d);
87 }
88 
89 int
90 gelf_update_shdr(Elf_Scn *scn, GElf_Shdr *s)
91 {
92 	int ec;
93 	Elf *e;
94 	Elf32_Shdr *sh32;
95 
96 
97 	if (s == NULL || scn == NULL || (e = scn->s_elf) == NULL ||
98 	    e->e_kind != ELF_K_ELF ||
99 	    ((ec = e->e_class) != ELFCLASS32 && ec != ELFCLASS64)) {
100 		LIBELF_SET_ERROR(ARGUMENT, 0);
101 		return (0);
102 	}
103 
104 	if (e->e_cmd == ELF_C_READ) {
105 		LIBELF_SET_ERROR(MODE, 0);
106 		return (0);
107 	}
108 
109 	(void) elf_flagscn(scn, ELF_C_SET, ELF_F_DIRTY);
110 
111 	if (ec == ELFCLASS64) {
112 		scn->s_shdr.s_shdr64 = *s;
113 		return (1);
114 	}
115 
116 	sh32 = &scn->s_shdr.s_shdr32;
117 
118 	sh32->sh_name	 =  s->sh_name;
119 	sh32->sh_type	 =  s->sh_type;
120 	LIBELF_COPY_U32(sh32, s, sh_flags);
121 	LIBELF_COPY_U32(sh32, s, sh_addr);
122 	LIBELF_COPY_U32(sh32, s, sh_offset);
123 	LIBELF_COPY_U32(sh32, s, sh_size);
124 	sh32->sh_link	 =  s->sh_link;
125 	sh32->sh_info	 =  s->sh_info;
126 	LIBELF_COPY_U32(sh32, s, sh_addralign);
127 	LIBELF_COPY_U32(sh32, s, sh_entsize);
128 
129 	return (1);
130 }
131