xref: /freebsd/contrib/elftoolchain/libelf/gelf_ehdr.c (revision 7661de35d15f582ab33e3bd6b8d909601557e436)
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 <string.h>
34 
35 #include "_libelf.h"
36 
37 ELFTC_VCSID("$Id: gelf_ehdr.c 2268 2011-12-03 17:05:11Z jkoshy $");
38 
39 Elf32_Ehdr *
40 elf32_getehdr(Elf *e)
41 {
42 	return (_libelf_ehdr(e, ELFCLASS32, 0));
43 }
44 
45 Elf64_Ehdr *
46 elf64_getehdr(Elf *e)
47 {
48 	return (_libelf_ehdr(e, ELFCLASS64, 0));
49 }
50 
51 GElf_Ehdr *
52 gelf_getehdr(Elf *e, GElf_Ehdr *d)
53 {
54 	int ec;
55 	Elf32_Ehdr *eh32;
56 	Elf64_Ehdr *eh64;
57 
58 	if (d == NULL || e == NULL ||
59 	    ((ec = e->e_class) != ELFCLASS32 && ec != ELFCLASS64)) {
60 		LIBELF_SET_ERROR(ARGUMENT, 0);
61 		return (NULL);
62 	}
63 
64 	if (ec == ELFCLASS32) {
65 		if ((eh32 = _libelf_ehdr(e, ELFCLASS32, 0)) == NULL)
66 			return (NULL);
67 
68 		(void) memcpy(d->e_ident, eh32->e_ident,
69 		    sizeof(eh32->e_ident));
70 		d->e_type		= eh32->e_type;
71 		d->e_machine		= eh32->e_machine;
72 		d->e_version		= eh32->e_version;
73 		d->e_entry		= eh32->e_entry;
74 		d->e_phoff		= eh32->e_phoff;
75 		d->e_shoff		= eh32->e_shoff;
76 		d->e_flags		= eh32->e_flags;
77 		d->e_ehsize		= eh32->e_ehsize;
78 		d->e_phentsize		= eh32->e_phentsize;
79 		d->e_phnum		= eh32->e_phnum;
80 		d->e_shentsize		= eh32->e_shentsize;
81 		d->e_shnum		= eh32->e_shnum;
82 		d->e_shstrndx		= eh32->e_shstrndx;
83 
84 		return (d);
85 	}
86 
87 	assert(ec == ELFCLASS64);
88 
89 	if ((eh64 = _libelf_ehdr(e, ELFCLASS64, 0)) == NULL)
90 		return (NULL);
91 	*d = *eh64;
92 
93 	return (d);
94 }
95 
96 Elf32_Ehdr *
97 elf32_newehdr(Elf *e)
98 {
99 	return (_libelf_ehdr(e, ELFCLASS32, 1));
100 }
101 
102 Elf64_Ehdr *
103 elf64_newehdr(Elf *e)
104 {
105 	return (_libelf_ehdr(e, ELFCLASS64, 1));
106 }
107 
108 void *
109 gelf_newehdr(Elf *e, int ec)
110 {
111 	if (e != NULL &&
112 	    (ec == ELFCLASS32 || ec == ELFCLASS64))
113 		return (_libelf_ehdr(e, ec, 1));
114 
115 	LIBELF_SET_ERROR(ARGUMENT, 0);
116 	return (NULL);
117 }
118 
119 int
120 gelf_update_ehdr(Elf *e, GElf_Ehdr *s)
121 {
122 	int ec;
123 	void *ehdr;
124 	Elf32_Ehdr *eh32;
125 	Elf64_Ehdr *eh64;
126 
127 	if (s== NULL || e == NULL || e->e_kind != ELF_K_ELF ||
128 	    ((ec = e->e_class) != ELFCLASS32 && ec != ELFCLASS64)) {
129 		LIBELF_SET_ERROR(ARGUMENT, 0);
130 		return (0);
131 	}
132 
133 	if (e->e_cmd == ELF_C_READ) {
134 		LIBELF_SET_ERROR(MODE, 0);
135 		return (0);
136 	}
137 
138 	if ((ehdr = _libelf_ehdr(e, ec, 0)) == NULL)
139 		return (0);
140 
141 	(void) elf_flagehdr(e, ELF_C_SET, ELF_F_DIRTY);
142 
143 	if (ec == ELFCLASS64) {
144 		eh64 = (Elf64_Ehdr *) ehdr;
145 		*eh64 = *s;
146 		return (1);
147 	}
148 
149 	eh32 = (Elf32_Ehdr *) ehdr;
150 
151 	(void) memcpy(eh32->e_ident, s->e_ident, sizeof(eh32->e_ident));
152 
153 	eh32->e_type      = s->e_type;
154 	eh32->e_machine   = s->e_machine;
155 	eh32->e_version   = s->e_version;
156 	LIBELF_COPY_U32(eh32, s, e_entry);
157 	LIBELF_COPY_U32(eh32, s, e_phoff);
158 	LIBELF_COPY_U32(eh32, s, e_shoff);
159 	eh32->e_flags     = s->e_flags;
160 	eh32->e_ehsize    = s->e_ehsize;
161 	eh32->e_phentsize = s->e_phentsize;
162 	eh32->e_phnum     = s->e_phnum;
163 	eh32->e_shentsize = s->e_shentsize;
164 	eh32->e_shnum     = s->e_shnum;
165 	eh32->e_shstrndx  = s->e_shstrndx;
166 
167 	return (1);
168 }
169