1/* Update program header program header table entry.
2   Copyright (C) 2000-2010 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_phdr (Elf *elf, int ndx, GElf_Phdr *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_Phdr *phdr = elf->state.elf32.phdr;
59
60      /* We have to convert the data to the 32 bit format.  This might
61	 overflow some fields so we have to test for this case before
62	 copying.  */
63      if (unlikely (src->p_offset > 0xffffffffull)
64	  || unlikely (src->p_vaddr > 0xffffffffull)
65	  || unlikely (src->p_paddr > 0xffffffffull)
66	  || unlikely (src->p_filesz > 0xffffffffull)
67	  || unlikely (src->p_memsz > 0xffffffffull)
68	  || unlikely (src->p_align > 0xffffffffull))
69	{
70	  __libelf_seterrno (ELF_E_INVALID_DATA);
71	  goto out;
72	}
73
74      if (phdr == NULL)
75	{
76	  phdr = __elf32_getphdr_wrlock (elf);
77	  if (phdr == NULL)
78	    /* The error number is already set.  */
79	    goto out;
80	}
81
82      /* Test whether the index is ok.  */
83      size_t phnum;
84      if (ndx >= elf->state.elf32.ehdr->e_phnum
85	  && (elf->state.elf32.ehdr->e_phnum != PN_XNUM
86	      || __elf_getphdrnum_rdlock (elf, &phnum) != 0
87	      || (size_t) ndx >= phnum))
88	{
89	  __libelf_seterrno (ELF_E_INVALID_INDEX);
90	  goto out;
91	}
92
93      /* Now correct the pointer to point to the correct element.  */
94      phdr += ndx;
95
96#define COPY(name) \
97      phdr->name = src->name
98      COPY (p_type);
99      COPY (p_offset);
100      COPY (p_vaddr);
101      COPY (p_paddr);
102      COPY (p_filesz);
103      COPY (p_memsz);
104      COPY (p_flags);
105      COPY (p_align);
106    }
107  else
108    {
109      Elf64_Phdr *phdr = elf->state.elf64.phdr;
110
111      if (phdr == NULL)
112	{
113	  phdr = __elf64_getphdr_wrlock (elf);
114	  if (phdr == NULL)
115	    /* The error number is already set.  */
116	    goto out;
117	}
118
119      /* Test whether the index is ok.  */
120      size_t phnum;
121      if (ndx >= elf->state.elf64.ehdr->e_phnum
122	  && (elf->state.elf64.ehdr->e_phnum != PN_XNUM
123	      || __elf_getphdrnum_rdlock (elf, &phnum) != 0
124	      || (size_t) ndx >= phnum))
125	{
126	  __libelf_seterrno (ELF_E_INVALID_INDEX);
127	  goto out;
128	}
129
130      /* Just copy the data.  */
131      memcpy (phdr + ndx, src, sizeof (Elf64_Phdr));
132    }
133
134  /* Mark the program header as modified.  */
135  elf->state.elf.phdr_flags |= ELF_F_DIRTY;
136
137  result = 1;
138
139 out:
140  rwlock_unlock (elf->lock);
141
142  return result;
143}
144