blob: fde4d544415b6c9b1ef9dfdbb75eb391a9469f12 [file] [log] [blame]
/*
* Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 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.
*
* Neither the name of ARM 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 HOLDER 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 <assert.h>
#include <auth/auth_mod.h>
#include <platform.h>
#include <platform_oid.h>
#include <string.h>
/*
* Store a new non-volatile counter value. This implementation
* only allows updating of the platform's Trusted NV counter when a
* certificate protected by the Trusted NV counter is signed with
* the ROT key. This avoids a compromised secondary certificate from
* updating the platform's Trusted NV counter, which could lead to the
* platform becoming unusable. The function is suitable for all TBBR
* compliant platforms.
*
* Return: 0 = success, Otherwise = error
*/
int plat_set_nv_ctr2(void *cookie, const auth_img_desc_t *img_desc,
unsigned int nv_ctr)
{
int trusted_nv_ctr;
assert(cookie != NULL);
assert(img_desc != NULL);
trusted_nv_ctr = strcmp(cookie, TRUSTED_FW_NVCOUNTER_OID) == 0;
/*
* Only update the Trusted NV Counter if the certificate
* has been signed with the ROT key. Non Trusted NV counter
* updates are unconditional.
*/
if (!trusted_nv_ctr || img_desc->parent == NULL)
return plat_set_nv_ctr(cookie, nv_ctr);
/*
* Trusted certificates not signed with the ROT key are not
* allowed to update the Trusted NV Counter.
*/
return 1;
}