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/*
* Copyright 2017 The Chromium OS Authors. All rights reserved.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "common.h"
#include "console.h"
#include "tpm_nvmem_ops.h"
/* These come from the tpm2 tree. */
#include "Global.h"
#include "Implementation.h"
#include "NV_fp.h"
#include "tpm_types.h"
#define CPRINTF(format, args...) cprintf(CC_TASK, format, ## args)
enum tpm_read_rv read_tpm_nvmem(uint16_t obj_index,
uint16_t obj_size, void *obj_value)
{
TPM_HANDLE object_handle;
NV_INDEX nvIndex;
object_handle = HR_NV_INDEX + obj_index;
if (!NvEarlyStageFindHandle(object_handle)) {
CPRINTF("%s: object at 0x%x not found\n", __func__, obj_index);
return tpm_read_not_found;
}
/* Get properties of this index as stored in nvmem. */
NvGetIndexInfo(object_handle, &nvIndex);
/*
* We presume it is readable and are not checking the access
* limitations.
*/
/*
* Does the caller ask for too much? Note that we always read from the
* beginning of the space, unlike the actual TPM2_NV_Read command
* which can start at an offset.
*/
if (obj_size > nvIndex.publicArea.dataSize) {
CPRINTF("%s: object at 0x%x is smaller than %d\n",
__func__, obj_index, obj_size);
return tpm_read_too_small;
}
/* Perform the read. */
NvGetIndexData(object_handle, &nvIndex, 0, obj_size, obj_value);
return tpm_read_success;
}
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