1/* Update ELF header.
2   Copyright (C) 2000, 2001, 2002, 2010 Red Hat, Inc.
3   This file is part of elfutils.
4   Written by Ulrich Drepper <drepper@redhat.com>, 2000.
5
6   This file is free software; you can redistribute it and/or modify
7   it under the terms of either
8
9     * the GNU Lesser General Public License as published by the Free
10       Software Foundation; either version 3 of the License, or (at
11       your option) any later version
12
13   or
14
15     * the GNU General Public License as published by the Free
16       Software Foundation; either version 2 of the License, or (at
17       your option) any later version
18
19   or both in parallel, as here.
20
21   elfutils is distributed in the hope that it will be useful, but
22   WITHOUT ANY WARRANTY; without even the implied warranty of
23   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
24   General Public License for more details.
25
26   You should have received copies of the GNU General Public License and
27   the GNU Lesser General Public License along with this program.  If
28   not, see <http://www.gnu.org/licenses/>.  */
29
30#ifdef HAVE_CONFIG_H
31# include <config.h>
32#endif
33
34#include <gelf.h>
35#include <string.h>
36
37#include "libelfP.h"
38
39
40int
41gelf_update_ehdr (Elf *elf, GElf_Ehdr *src)
42{
43  int result = 0;
44
45  if (elf == NULL)
46    return 0;
47
48  if (unlikely (elf->kind != ELF_K_ELF))
49    {
50      __libelf_seterrno (ELF_E_INVALID_HANDLE);
51      return 0;
52    }
53
54  rwlock_wrlock (elf->lock);
55
56  if (elf->class == ELFCLASS32)
57    {
58      Elf32_Ehdr *ehdr = elf->state.elf32.ehdr;
59
60      if (ehdr == NULL)
61	{
62	  __libelf_seterrno (ELF_E_WRONG_ORDER_EHDR);
63	  goto out;
64	}
65
66      /* We have to convert the data to the 32 bit format.  This might
67	 overflow some fields so we have to test for this case before
68	 copying.  */
69      if (unlikely (src->e_entry > 0xffffffffull)
70	  || unlikely (src->e_phoff > 0xffffffffull)
71	  || unlikely (src->e_shoff > 0xffffffffull))
72	{
73	  __libelf_seterrno (ELF_E_INVALID_DATA);
74	  goto out;
75	}
76
77      /* Copy the data.  */
78      memcpy (ehdr->e_ident, src->e_ident, EI_NIDENT);
79#define COPY(name) \
80      ehdr->name = src->name
81      COPY (e_type);
82      COPY (e_machine);
83      COPY (e_version);
84      COPY (e_entry);
85      COPY (e_phoff);
86      COPY (e_shoff);
87      COPY (e_flags);
88      COPY (e_ehsize);
89      COPY (e_phentsize);
90      COPY (e_phnum);
91      COPY (e_shentsize);
92      COPY (e_shnum);
93      COPY (e_shstrndx);
94    }
95  else
96    {
97      Elf64_Ehdr *ehdr = elf->state.elf64.ehdr;
98
99      if (ehdr == NULL)
100	{
101	  __libelf_seterrno (ELF_E_WRONG_ORDER_EHDR);
102	  goto out;
103	}
104
105      /* Just copy the data.  */
106      memcpy (ehdr, src, sizeof (Elf64_Ehdr));
107    }
108
109  /* Mark the ELF header as modified.  */
110  elf->state.elf.ehdr_flags |= ELF_F_DIRTY;
111
112  result = 1;
113
114 out:
115  rwlock_unlock (elf->lock);
116
117  return result;
118}
119