nuttx/binfmt/libelf/libelf_verify.c

121 lines
4.2 KiB
C

/****************************************************************************
* binfmt/libelf/elf_verify.c
*
* Copyright (C) 2012 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* 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.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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
* COPYRIGHT OWNER 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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <string.h>
#include <debug.h>
#include <errno.h>
#include <nuttx/binfmt/elf.h>
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/****************************************************************************
* Private Constant Data
****************************************************************************/
static const char g_elfmagic[EI_MAGIC_SIZE] = { 0x7f, 'E', 'L', 'F' };
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: elf_verifyheader
*
* Description:
* Given the header from a possible ELF executable, verify that it
* is an ELF executable.
*
* Returned Value:
* 0 (OK) is returned on success and a negated errno is returned on
* failure.
*
* -ENOEXEC : Not an ELF file
* -EINVAL : Not a relocatable ELF file or not supported by the current,
* configured architecture.
*
****************************************************************************/
int elf_verifyheader(FAR const Elf32_Ehdr *ehdr)
{
if (!ehdr)
{
bdbg("NULL ELF header!");
return -ENOEXEC;
}
/* Verify that the magic number indicates an ELF file */
if (memcmp(ehdr->e_ident, g_elfmagic, EI_MAGIC_SIZE) != 0)
{
bvdbg("Not ELF magic {%02x, %02x, %02x, %02x}\n",
ehdr->e_ident[0], ehdr->e_ident[1], ehdr->e_ident[2], ehdr->e_ident[3]);
return -ENOEXEC;
}
/* Verify that this is a relocatable file */
if (ehdr->e_type != ET_REL)
{
bdbg("Not a relocatable file: e_type=%d\n", ehdr->e_type);
return -EINVAL;
}
/* Verify that this file works with the currently configured architecture */
if (up_checkarch(ehdr))
{
bdbg("Not a supported architecture\n");
return -ENOEXEC;
}
/* Looks good so far... we still might find some problems later. */
return OK;
}