pal_plat_rot.cpp

00001 /*******************************************************************************
00002  * Copyright 2016-2018 ARM Ltd.
00003  *
00004  * Licensed under the Apache License, Version 2.0 (the "License");
00005  * you may not use this file except in compliance with the License.
00006  * You may obtain a copy of the License at
00007  *
00008  *     http://www.apache.org/licenses/LICENSE-2.0
00009  *
00010  * Unless required by applicable law or agreed to in writing, software
00011  * distributed under the License is distributed on an "AS IS" BASIS,
00012  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00013  * See the License for the specific language governing permissions and
00014  * limitations under the License.
00015  *******************************************************************************/
00016 #ifdef MBED_CONF_MBED_CLOUD_CLIENT_EXTERNAL_SST_SUPPORT
00017 #include "pal.h"
00018 #include "pal_plat_rot.h"
00019 #include "KVMap.h"
00020 #include "mbed_error.h"
00021 #include "TDBStore.h"
00022 #include "DeviceKey.h"
00023 
00024 #define MAX_DEVICE_KEY_SIZE_IN_BYTES DEVICE_KEY_32BYTE
00025 
00026 using namespace mbed;
00027 // If there is no "HW ROT", this code is enabled. It will in practice either use a pre-generated
00028 // ROT in SOTP or generate it once on the fly.
00029 #if (PAL_USE_HW_ROT == 0)
00030 
00031 
00032 #define TRACE_GROUP "PAL"
00033 
00034 palStatus_t pal_plat_osGetRoT(uint8_t * key, size_t keyLenBytes)
00035 {
00036     int  error;
00037     KVMap &kv_map = KVMap::get_instance();
00038     KVStore *inner_store = kv_map.get_internal_kv_instance(NULL);
00039 
00040     //Check key buffer
00041     if (key == NULL) {
00042         return PAL_ERR_INVALID_ARGUMENT ;
00043     }
00044     //Check key buffer size
00045     if (keyLenBytes != PAL_DEVICE_KEY_SIZE_IN_BYTES) {
00046         return PAL_ERR_INVALID_ARGUMENT ;
00047     }
00048     //Check internal instance 
00049     if (inner_store == NULL) {
00050         return PAL_ERR_NULL_POINTER ;
00051     }
00052 
00053     //Read ROT
00054     error = ((TDBStore *)inner_store)->reserved_data_get(key, keyLenBytes);
00055     if (error != MBED_SUCCESS) {
00056         if (error == MBED_ERROR_ITEM_NOT_FOUND) {
00057             return PAL_ERR_ITEM_NOT_EXIST ;
00058         }
00059         return PAL_ERR_GENERIC_FAILURE ;
00060     }
00061 
00062     return PAL_SUCCESS;
00063 }
00064 palStatus_t pal_plat_osSetRoT(uint8_t * key, size_t keyLenBytes)
00065 {
00066     int  error;
00067     DeviceKey &devkey = DeviceKey::get_instance();
00068 
00069     //Check key buffer
00070     if (key == NULL) {
00071         return PAL_ERR_INVALID_ARGUMENT ;
00072     }
00073     //Check key buffer size
00074     if (keyLenBytes != PAL_DEVICE_KEY_SIZE_IN_BYTES) {
00075         return PAL_ERR_INVALID_ARGUMENT ;
00076     }
00077 
00078     //Set ROT
00079     error = devkey.device_inject_root_of_trust((uint32_t*)key, keyLenBytes);
00080     if (error != MBED_SUCCESS) {
00081         if (error == DEVICEKEY_ALREADY_EXIST) {
00082             return PAL_ERR_ITEM_EXIST ;
00083         }
00084         return PAL_ERR_GENERIC_FAILURE ;
00085     }
00086 
00087     return PAL_SUCCESS;
00088 }
00089 #endif // (PAL_USE_HW_ROT == 0)
00090 #endif //#ifdef MBED_CONF_MBED_CLOUD_CLIENT_EXTERNAL_SST_SUPPORT