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/* Test program for adding a program header to a vendor specific ELF file.
Copyright (C) 2016 Red Hat, Inc.
This file is part of elfutils.
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 <inttypes.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include ELFUTILS_HEADER(elf)
#include <gelf.h>
void
check_elf (const char *fname, int class, int use_mmap)
{
printf ("\nfname: %s\n", fname);
int 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 *elf = elf_begin (fd, use_mmap ? ELF_C_WRITE_MMAP : ELF_C_WRITE, NULL);
if (elf == NULL)
{
printf ("cannot create ELF descriptor: %s\n", elf_errmsg (-1));
exit (1);
}
// Create an ELF header.
if (gelf_newehdr (elf, class) == 0)
{
printf ("cannot create ELF header: %s\n", elf_errmsg (-1));
exit (1);
}
GElf_Ehdr ehdr_mem;
GElf_Ehdr *ehdr = gelf_getehdr (elf, &ehdr_mem);
if (ehdr == NULL)
{
printf ("cannot get ELF header: %s\n", elf_errmsg (-1));
exit (1);
}
// Initialize header.
ehdr->e_ident[EI_DATA] = class == ELFCLASS64 ? ELFDATA2LSB : ELFDATA2MSB;
ehdr->e_ident[EI_OSABI] = ELFOSABI_GNU;
ehdr->e_type = ET_LOOS + 1;
ehdr->e_machine = EM_X86_64;
ehdr->e_version = EV_CURRENT;
if (gelf_update_ehdr (elf, ehdr) == 0)
{
printf ("cannot update ELF header: %s\n", elf_errmsg (-1));
exit (1);
}
// Create a program header.
if (gelf_newphdr (elf, 1) == 0)
{
printf ("cannot create program header: %s\n", elf_errmsg (-1));
exit (1);
}
GElf_Phdr phdr;
if (gelf_getphdr (elf, 0, &phdr) == NULL)
{
printf ("cannot get program header: %s\n", elf_errmsg (-1));
exit (1);
}
// Some random values to check later.
phdr.p_type = PT_NULL;
phdr.p_offset = 0;
phdr.p_vaddr = 0;
phdr.p_paddr = 1;
phdr.p_filesz = 0;
phdr.p_memsz = 1024;
phdr.p_flags = PF_R;
phdr.p_align = 16;
if (gelf_update_phdr (elf, 0, &phdr) == 0)
{
printf ("cannot update program header: %s\n", elf_errmsg (-1));
exit (1);
}
// Write everything to disk.
if (elf_update (elf, ELF_C_WRITE) < 0)
{
printf ("failure in elf_update(WRITE): %s\n", elf_errmsg (-1));
exit (1);
}
if (elf_end (elf) != 0)
{
printf ("failure in elf_end: %s\n", elf_errmsg (-1));
exit (1);
}
close (fd);
/* Reread the ELF from disk now. */
fd = open (fname, O_RDONLY, 0666);
if (fd == -1)
{
printf ("cannot open `%s' read-only: %s\n", fname, strerror (errno));
exit (1);
}
elf = elf_begin (fd, use_mmap ? ELF_C_READ_MMAP : ELF_C_READ, NULL);
if (elf == NULL)
{
printf ("cannot create ELF descriptor read-only: %s\n", elf_errmsg (-1));
exit (1);
}
// Is our phdr there?
size_t phnum;
if (elf_getphdrnum (elf, &phnum) != 0)
{
printf ("cannot get phdr num: %s\n", elf_errmsg (-1));
exit (1);
}
if (phnum != 1)
{
printf ("Expected just 1 phdr, got: %zd\n", phnum);
exit (1);
}
if (gelf_getphdr (elf, 0, &phdr) == NULL)
{
printf ("cannot get program header from file: %s\n", elf_errmsg (-1));
exit (1);
}
if (phdr.p_type != PT_NULL
|| phdr.p_offset != 0
|| phdr.p_vaddr != 0
|| phdr.p_paddr != 1
|| phdr.p_filesz != 0
|| phdr.p_memsz != 1024
|| phdr.p_flags != PF_R
|| phdr.p_align != 16)
{
printf ("Unexpected phdr values\n");
exit (1);
}
if (elf_end (elf) != 0)
{
printf ("failure in elf_end: %s\n", elf_errmsg (-1));
exit (1);
}
close (fd);
unlink (fname);
}
int
main (int argc __attribute__ ((unused)),
char *argv[] __attribute__ ((unused)))
{
elf_version (EV_CURRENT);
check_elf ("vendor.elf.32", ELFCLASS32, 0);
check_elf ("vendor.elf.32.mmap", ELFCLASS32, 1);
check_elf ("vendor.elf.64", ELFCLASS64, 0);
check_elf ("vendor.elf.64.mmap", ELFCLASS64, 1);
return 0;
}
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