xref: /freebsd/contrib/elftoolchain/libelf/gelf_ehdr.c (revision ec0e626bafb335b30c499d06066997f54b10c092)
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 <sys/cdefs.h>
28 
29 #include <assert.h>
30 #include <gelf.h>
31 #include <libelf.h>
32 #include <limits.h>
33 #include <stdint.h>
34 #include <string.h>
35 
36 #include "_libelf.h"
37 
38 ELFTC_VCSID("$Id: gelf_ehdr.c 2268 2011-12-03 17:05:11Z jkoshy $");
39 
40 Elf32_Ehdr *
41 elf32_getehdr(Elf *e)
42 {
43 	return (_libelf_ehdr(e, ELFCLASS32, 0));
44 }
45 
46 Elf64_Ehdr *
47 elf64_getehdr(Elf *e)
48 {
49 	return (_libelf_ehdr(e, ELFCLASS64, 0));
50 }
51 
52 GElf_Ehdr *
53 gelf_getehdr(Elf *e, GElf_Ehdr *d)
54 {
55 	int ec;
56 	Elf32_Ehdr *eh32;
57 	Elf64_Ehdr *eh64;
58 
59 	if (d == NULL || e == NULL ||
60 	    ((ec = e->e_class) != ELFCLASS32 && ec != ELFCLASS64)) {
61 		LIBELF_SET_ERROR(ARGUMENT, 0);
62 		return (NULL);
63 	}
64 
65 	if (ec == ELFCLASS32) {
66 		if ((eh32 = _libelf_ehdr(e, ELFCLASS32, 0)) == NULL)
67 			return (NULL);
68 
69 		(void) memcpy(d->e_ident, eh32->e_ident,
70 		    sizeof(eh32->e_ident));
71 		d->e_type		= eh32->e_type;
72 		d->e_machine		= eh32->e_machine;
73 		d->e_version		= eh32->e_version;
74 		d->e_entry		= eh32->e_entry;
75 		d->e_phoff		= eh32->e_phoff;
76 		d->e_shoff		= eh32->e_shoff;
77 		d->e_flags		= eh32->e_flags;
78 		d->e_ehsize		= eh32->e_ehsize;
79 		d->e_phentsize		= eh32->e_phentsize;
80 		d->e_phnum		= eh32->e_phnum;
81 		d->e_shentsize		= eh32->e_shentsize;
82 		d->e_shnum		= eh32->e_shnum;
83 		d->e_shstrndx		= eh32->e_shstrndx;
84 
85 		return (d);
86 	}
87 
88 	assert(ec == ELFCLASS64);
89 
90 	if ((eh64 = _libelf_ehdr(e, ELFCLASS64, 0)) == NULL)
91 		return (NULL);
92 	*d = *eh64;
93 
94 	return (d);
95 }
96 
97 Elf32_Ehdr *
98 elf32_newehdr(Elf *e)
99 {
100 	return (_libelf_ehdr(e, ELFCLASS32, 1));
101 }
102 
103 Elf64_Ehdr *
104 elf64_newehdr(Elf *e)
105 {
106 	return (_libelf_ehdr(e, ELFCLASS64, 1));
107 }
108 
109 void *
110 gelf_newehdr(Elf *e, int ec)
111 {
112 	if (e != NULL &&
113 	    (ec == ELFCLASS32 || ec == ELFCLASS64))
114 		return (_libelf_ehdr(e, ec, 1));
115 
116 	LIBELF_SET_ERROR(ARGUMENT, 0);
117 	return (NULL);
118 }
119 
120 int
121 gelf_update_ehdr(Elf *e, GElf_Ehdr *s)
122 {
123 	int ec;
124 	void *ehdr;
125 	Elf32_Ehdr *eh32;
126 	Elf64_Ehdr *eh64;
127 
128 	if (s== NULL || e == NULL || e->e_kind != ELF_K_ELF ||
129 	    ((ec = e->e_class) != ELFCLASS32 && ec != ELFCLASS64)) {
130 		LIBELF_SET_ERROR(ARGUMENT, 0);
131 		return (0);
132 	}
133 
134 	if (e->e_cmd == ELF_C_READ) {
135 		LIBELF_SET_ERROR(MODE, 0);
136 		return (0);
137 	}
138 
139 	if ((ehdr = _libelf_ehdr(e, ec, 0)) == NULL)
140 		return (0);
141 
142 	(void) elf_flagehdr(e, ELF_C_SET, ELF_F_DIRTY);
143 
144 	if (ec == ELFCLASS64) {
145 		eh64 = (Elf64_Ehdr *) ehdr;
146 		*eh64 = *s;
147 		return (1);
148 	}
149 
150 	eh32 = (Elf32_Ehdr *) ehdr;
151 
152 	(void) memcpy(eh32->e_ident, s->e_ident, sizeof(eh32->e_ident));
153 
154 	eh32->e_type      = s->e_type;
155 	eh32->e_machine   = s->e_machine;
156 	eh32->e_version   = s->e_version;
157 	LIBELF_COPY_U32(eh32, s, e_entry);
158 	LIBELF_COPY_U32(eh32, s, e_phoff);
159 	LIBELF_COPY_U32(eh32, s, e_shoff);
160 	eh32->e_flags     = s->e_flags;
161 	eh32->e_ehsize    = s->e_ehsize;
162 	eh32->e_phentsize = s->e_phentsize;
163 	eh32->e_phnum     = s->e_phnum;
164 	eh32->e_shentsize = s->e_shentsize;
165 	eh32->e_shnum     = s->e_shnum;
166 	eh32->e_shstrndx  = s->e_shstrndx;
167 
168 	return (1);
169 }
170