101 lines
2.8 KiB
C
101 lines
2.8 KiB
C
/*-
|
|
* Copyright (c) 2006,2008 Joseph Koshy
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
|
|
#include <gelf.h>
|
|
|
|
#include "_libelf.h"
|
|
|
|
LIBELF_VCSID("$Id$");
|
|
|
|
static unsigned long
|
|
_libelf_sum(unsigned long c, const unsigned char *s, size_t size)
|
|
{
|
|
if (s == NULL || size == 0)
|
|
return (c);
|
|
|
|
while (size--)
|
|
c += *s++;
|
|
|
|
return (c);
|
|
}
|
|
|
|
unsigned long
|
|
_libelf_checksum(Elf *e, int elfclass)
|
|
{
|
|
size_t shn;
|
|
Elf_Scn *scn;
|
|
Elf_Data *d;
|
|
unsigned long checksum;
|
|
GElf_Ehdr eh;
|
|
GElf_Shdr shdr;
|
|
|
|
if (e == NULL) {
|
|
LIBELF_SET_ERROR(ARGUMENT, 0);
|
|
return (0L);
|
|
}
|
|
|
|
if (e->e_class != elfclass) {
|
|
LIBELF_SET_ERROR(CLASS, 0);
|
|
return (0L);
|
|
}
|
|
|
|
if (gelf_getehdr(e, &eh) == NULL)
|
|
return (0);
|
|
|
|
/*
|
|
* Iterate over all sections in the ELF file, computing the
|
|
* checksum along the way.
|
|
*
|
|
* The first section is always SHN_UNDEF and can be skipped.
|
|
* Non-allocatable sections are skipped, as are sections that
|
|
* could be affected by utilities such as strip(1).
|
|
*/
|
|
|
|
checksum = 0;
|
|
for (shn = 1; shn < e->e_u.e_elf.e_nscn; shn++) {
|
|
if ((scn = elf_getscn(e, shn)) == NULL)
|
|
return (0);
|
|
if (gelf_getshdr(scn, &shdr) == NULL)
|
|
return (0);
|
|
if ((shdr.sh_flags & SHF_ALLOC) == 0 ||
|
|
shdr.sh_type == SHT_DYNAMIC ||
|
|
shdr.sh_type == SHT_DYNSYM)
|
|
continue;
|
|
|
|
d = NULL;
|
|
while ((d = elf_rawdata(scn, d)) != NULL)
|
|
checksum = _libelf_sum(checksum,
|
|
(unsigned char *) d->d_buf, d->d_size);
|
|
}
|
|
|
|
/*
|
|
* Return a 16-bit checksum compatible with Solaris.
|
|
*/
|
|
return (((checksum >> 16) & 0xFFFFUL) + (checksum & 0xFFFFUL));
|
|
}
|