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/* Test program for elf_update function.
Copyright (C) 2000, 2002, 2005, 2016 Red Hat, Inc.
This file is part of elfutils.
Written by Ulrich Drepper <drepper@redhat.com>, 2000.
This file is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
elfutils is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <errno.h>
#include <fcntl.h>
#include <libelf.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include ELFUTILS_HEADER(dwelf)
int
main (int argc, char *argv[] __attribute__ ((unused)))
{
const char *fname = "xxx_update3";
int fd;
Elf *elf;
Elf32_Ehdr *ehdr;
Elf32_Phdr *phdr;
Elf_Scn *scn;
Elf32_Shdr *shdr;
Elf_Data *data;
Dwelf_Strtab *shst;
Dwelf_Strent *shstrtabse;
int i;
fd = open (fname, O_RDWR | O_CREAT | O_TRUNC, 0666);
if (fd == -1)
{
printf ("cannot open `%s': %s\n", fname, strerror (errno));
exit (1);
}
elf_version (EV_CURRENT);
elf_fill (0x42);
elf = elf_begin (fd, ELF_C_WRITE, NULL);
if (elf == NULL)
{
printf ("cannot create ELF descriptor: %s\n", elf_errmsg (-1));
exit (1);
}
/* Create an ELF header. */
ehdr = elf32_newehdr (elf);
if (ehdr == NULL)
{
printf ("cannot create ELF header: %s\n", elf_errmsg (-1));
exit (1);
}
/* Print the ELF header values. */
if (argc > 1)
{
for (i = 0; i < EI_NIDENT; ++i)
printf (" %02x", ehdr->e_ident[i]);
printf ("\
\ntype = %hu\nmachine = %hu\nversion = %u\nentry = %u\nphoff = %u\n"
"shoff = %u\nflags = %u\nehsize = %hu\nphentsize = %hu\n"
"phnum = %hu\nshentsize = %hu\nshnum = %hu\nshstrndx = %hu\n",
ehdr->e_type, ehdr->e_machine, ehdr->e_version, ehdr->e_entry,
ehdr->e_phoff, ehdr->e_shoff, ehdr->e_flags, ehdr->e_ehsize,
ehdr->e_phentsize, ehdr->e_phnum, ehdr->e_shentsize,
ehdr->e_shnum, ehdr->e_shstrndx);
}
ehdr->e_ident[0] = 42;
ehdr->e_ident[4] = 1;
ehdr->e_ident[5] = 1;
ehdr->e_ident[6] = 2;
ehdr->e_type = ET_EXEC;
ehdr->e_version = 1;
ehdr->e_ehsize = 1;
elf_flagehdr (elf, ELF_C_SET, ELF_F_DIRTY);
/* Create the program header. */
phdr = elf32_newphdr (elf, 1);
if (phdr == NULL)
{
printf ("cannot create program header: %s\n", elf_errmsg (-1));
exit (1);
}
phdr[0].p_type = PT_PHDR;
elf_flagphdr (elf, ELF_C_SET, ELF_F_DIRTY);
shst = dwelf_strtab_init (true);
scn = elf_newscn (elf);
if (scn == NULL)
{
printf ("cannot create SHSTRTAB section: %s\n", elf_errmsg (-1));
exit (1);
}
shdr = elf32_getshdr (scn);
if (shdr == NULL)
{
printf ("cannot get header for SHSTRTAB section: %s\n", elf_errmsg (-1));
exit (1);
}
shstrtabse = dwelf_strtab_add (shst, ".shstrtab");
shdr->sh_type = SHT_STRTAB;
shdr->sh_flags = 0;
shdr->sh_addr = 0;
shdr->sh_link = SHN_UNDEF;
shdr->sh_info = SHN_UNDEF;
shdr->sh_addralign = 1;
shdr->sh_entsize = 0;
/* We have to store the section index in the ELF header. */
ehdr->e_shstrndx = elf_ndxscn (scn);
data = elf_newdata (scn);
if (data == NULL)
{
printf ("cannot create data SHSTRTAB section: %s\n", elf_errmsg (-1));
exit (1);
}
/* No more sections, finalize the section header string table. */
dwelf_strtab_finalize (shst, data);
shdr->sh_name = dwelf_strent_off (shstrtabse);
/* Let the library compute the internal structure information. */
if (elf_update (elf, ELF_C_NULL) < 0)
{
printf ("failure in elf_update(NULL): %s\n", elf_errmsg (-1));
exit (1);
}
ehdr = elf32_getehdr (elf);
phdr[0].p_offset = ehdr->e_phoff;
phdr[0].p_offset = ehdr->e_phoff;
phdr[0].p_vaddr = ehdr->e_phoff;
phdr[0].p_paddr = ehdr->e_phoff;
phdr[0].p_flags = PF_R | PF_X;
phdr[0].p_filesz = ehdr->e_phnum * elf32_fsize (ELF_T_PHDR, 1, EV_CURRENT);
phdr[0].p_memsz = ehdr->e_phnum * elf32_fsize (ELF_T_PHDR, 1, EV_CURRENT);
phdr[0].p_align = sizeof (Elf32_Word);
/* Write out the file. */
if (elf_update (elf, ELF_C_WRITE) < 0)
{
printf ("failure in elf_update(WRITE): %s\n", elf_errmsg (-1));
exit (1);
}
/* We don't need the string table anymore. */
dwelf_strtab_free (shst);
/* And the data allocated in the .shstrtab section. */
free (data->d_buf);
/* Print the ELF header values. */
if (argc > 1)
{
for (i = 0; i < EI_NIDENT; ++i)
printf (" %02x", ehdr->e_ident[i]);
printf ("\
\ntype = %hu\nmachine = %hu\nversion = %u\nentry = %u\nphoff = %u\n"
"shoff = %u\nflags = %u\nehsize = %hu\nphentsize = %hu\n"
"phnum = %hu\nshentsize = %hu\nshnum = %hu\nshstrndx = %hu\n",
ehdr->e_type, ehdr->e_machine, ehdr->e_version, ehdr->e_entry,
ehdr->e_phoff, ehdr->e_shoff, ehdr->e_flags, ehdr->e_ehsize,
ehdr->e_phentsize, ehdr->e_phnum, ehdr->e_shentsize,
ehdr->e_shnum, ehdr->e_shstrndx);
}
if (elf_end (elf) != 0)
{
printf ("failure in elf_end: %s\n", elf_errmsg (-1));
exit (1);
}
unlink (fname);
return 0;
}
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