elfshphehdr.c revision c53857b6a8b074c724999009b8d70b6b6e0c0f15
1/* Test program for adding section and program headers and ehdr updates.
2   Copyright (C) 2015 Red Hat, Inc.
3   This file is part of elfutils.
4
5   This file is free software; you can redistribute it and/or modify
6   it under the terms of the GNU General Public License as published by
7   the Free Software Foundation; either version 3 of the License, or
8   (at your option) any later version.
9
10   elfutils is distributed in the hope that it will be useful, but
11   WITHOUT ANY WARRANTY; without even the implied warranty of
12   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13   GNU General Public License for more details.
14
15   You should have received a copy of the GNU General Public License
16   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
17
18#include <config.h>
19#include <assert.h>
20#include ELFUTILS_HEADER(elf)
21#include <gelf.h>
22
23#include <stdio.h>
24#include <stdlib.h>
25
26#include <sys/types.h>
27#include <sys/stat.h>
28#include <fcntl.h>
29#include <unistd.h>
30
31#include <stdbool.h>
32
33void
34check (const char *msg, bool statement)
35{
36  if (! statement)
37    {
38      fprintf (stderr, "%s FAILED\n", msg);
39      exit (-1);
40    }
41  else
42    fprintf (stderr, "%s OK\n", msg);
43}
44
45void
46check_elf (const char *msg, bool statement)
47{
48  if (! statement)
49    {
50      fprintf (stderr, "%s: %s\n", msg, elf_errmsg (-1));
51      exit (-1);
52    }
53  else
54    fprintf (stderr, "%s OK\n", msg);
55}
56
57void
58test (Elf *elf, int class, bool layout)
59{
60  fprintf (stderr, "testing ELF class: %d, layout: %d\n", class, layout);
61
62  check_elf ("gelf_newehdr", gelf_newehdr (elf, class) != 0);
63  check_elf ("gelf_getclass", gelf_getclass (elf) == class);
64
65  check_elf ("elf_flagelf", elf_flagelf (elf, layout ? ELF_C_SET : ELF_C_CLR,
66					 ELF_F_LAYOUT) != 0);
67
68  GElf_Ehdr ehdr;
69  check_elf ("gelf_getehdr", gelf_getehdr (elf, &ehdr) != NULL);
70  check ("e_shnum == 0", ehdr.e_shnum == 0);
71  check ("e_phnum == 0", ehdr.e_phnum == 0);
72  check ("e_shoff == 0", ehdr.e_shoff == 0);
73  check ("e_phoff == 0", ehdr.e_phoff == 0);
74
75  size_t shnum;
76  check_elf ("elf_getshdrnum", elf_getshdrnum (elf, &shnum) == 0);
77  check ("shnum == 0", shnum == 0);
78
79  size_t phnum;
80  check_elf ("elf_getphdrnum", elf_getphdrnum (elf, &phnum) == 0);
81  check ("phnum == 0", phnum == 0);
82
83  /* Lets fill in some info we are always responsible for.  */
84  ehdr.e_ident[EI_DATA] = ELFDATANONE; /* Ask for native encoding.  */
85  ehdr.e_type = ET_EXEC;
86  ehdr.e_machine = EM_386;
87  ehdr.e_version = EV_NONE; /* Ask for current version. */
88  check_elf ("gelf_update_ehdr", gelf_update_ehdr (elf, &ehdr) != 0);
89
90  check_elf ("elf_update", elf_update (elf, ELF_C_NULL) > 0);
91
92  check_elf ("gelf_getehdr", gelf_getehdr (elf, &ehdr) != NULL);
93  check ("EI_DATA", ehdr.e_ident[EI_DATA] != ELFDATANONE);
94  check ("e_version", ehdr.e_version == EV_CURRENT);
95
96  /* The sh/ph values shouldn't have changed.  */
97  check ("e_shnum == 0", ehdr.e_shnum == 0);
98  check ("e_phnum == 0", ehdr.e_phnum == 0);
99  check ("e_shoff == 0", ehdr.e_shoff == 0);
100  check ("e_phoff == 0", ehdr.e_phoff == 0);
101
102  check_elf ("elf_getshdrnum", elf_getshdrnum (elf, &shnum) == 0);
103  check ("shnum == 0", shnum == 0);
104
105  check_elf ("elf_getphdrnum", elf_getphdrnum (elf, &phnum) == 0);
106  check ("phnum == 0", phnum == 0);
107
108  /* Lets add a header.  */
109  check_elf ("elf_newscn", elf_newscn (elf) != NULL);
110  check_elf ("gelf_newphdr", gelf_newphdr (elf, 1) != 0);
111
112  /* If we are responsible for the layout ourselves we should also
113     tell where to put them.  */
114  if (layout)
115    {
116      check_elf ("gelf_getehdr", gelf_getehdr (elf, &ehdr) != NULL);
117      /* phdrs go right after the ehdr.  */
118      ehdr.e_phoff = ehdr.e_ehsize;
119      /* shdrs go right after the phdrs.  */
120      ehdr.e_shoff = ehdr.e_phoff + ehdr.e_phnum * ehdr.e_phentsize;
121      check_elf ("gelf_update_ehdr", gelf_update_ehdr (elf, &ehdr) != 0);
122    }
123
124  check_elf ("elf_update", elf_update (elf, ELF_C_NULL) > 0);
125
126  check_elf ("elf_getshdrnum", elf_getshdrnum (elf, &shnum) == 0);
127  check ("shnum == 1", shnum == 2); /* section zero is also created.  */
128
129  check_elf ("elf_getphdrnum", elf_getphdrnum (elf, &phnum) != 0);
130  check ("phnum == 1", phnum == 1);
131
132  check_elf ("gelf_getehdr", gelf_getehdr (elf, &ehdr) != NULL);
133
134  check ("EI_DATA", ehdr.e_ident[EI_DATA] != ELFDATANONE);
135  check ("e_version", ehdr.e_version == EV_CURRENT);
136
137  check ("e_shnum == 2", ehdr.e_shnum == 2);
138  check ("e_phnum == 1", ehdr.e_phnum == 1);
139  check ("e_shoff != 0", ehdr.e_shoff != 0);
140  check ("e_phoff != 0", ehdr.e_phoff != 0);
141
142  size_t shentsize = (class == ELFCLASS32
143		      ? sizeof (Elf32_Shdr) : sizeof (Elf64_Shdr));
144  check ("e_shentsize", ehdr.e_shentsize == shentsize);
145  size_t phentsize = (class == ELFCLASS32
146		      ? sizeof (Elf32_Phdr) : sizeof (Elf64_Phdr));
147  check ("e_phentsize", ehdr.e_phentsize == phentsize);
148}
149
150int
151main (int argc __attribute__ ((unused)), char **argv __attribute ((unused)))
152{
153  elf_version (EV_CURRENT);
154
155  int fd = fd = open("/dev/zero", O_WRONLY);
156  check ("open", fd >= 0);
157
158  Elf *elf;
159
160  elf = elf_begin (fd, ELF_C_WRITE, NULL);
161  check_elf ("elf_begin", elf != NULL);
162  test (elf, ELFCLASS32, false);
163  elf_end (elf);
164
165  elf = elf_begin (fd, ELF_C_WRITE, NULL);
166  check_elf ("elf_begin", elf != NULL);
167  test (elf, ELFCLASS32, true);
168  elf_end (elf);
169
170  elf = elf_begin (fd, ELF_C_WRITE, NULL);
171  check_elf ("elf_begin", elf != NULL);
172  test (elf, ELFCLASS64, false);
173  elf_end (elf);
174
175  elf = elf_begin (fd, ELF_C_WRITE, NULL);
176  check_elf ("elf_begin", elf != NULL);
177  test (elf, ELFCLASS64, true);
178  elf_end (elf);
179
180  close (fd);
181  return 0;
182}
183