Maxim Integrated / Mbed 2 deprecated DeepCover Embedded Security in IoT

MAXREFDES143#: DeepCover Embedded Security in IoT Authenticated Sensing & Notification

Dependencies:   MaximInterface mbed

The MAXREFDES143# is an Internet of Things (IoT) embedded security reference design, built to protect an industrial sensing node by means of authentication and notification to a web server. The hardware includes a peripheral module representing a protected sensor node monitoring operating temperature and remaining life of a filter (simulated through ambient light sensing) and an mbed shield representing a controller node responsible for monitoring one or more sensor nodes. The design is hierarchical with each controller node communicating data from connected sensor nodes to a web server that maintains a centralized log and dispatches notifications as necessary. The mbed shield contains a Wi-Fi module, a DS2465 coprocessor with 1-Wire® master function, an LCD, LEDs, and pushbuttons. The protected sensor node contains a DS28E15 authenticator, a DS7505 temperature sensor, and a MAX44009 light sensor. The mbed shield communicates to a web server by the onboard Wi-Fi module and to the protected sensor node with I2C and 1-Wire. The MAXREFDES143# is equipped with a standard shield connector for immediate testing using an mbed board such as the MAX32600MBED#. The simplicity of this design enables rapid integration into any star-topology IoT network requiring the heightened security with low overhead provided by the SHA-256 symmetric-key algorithm.

More information about the MAXREFDES143# is available on the Maxim Integrated website.

SensorNode.cpp@1:e1c7c1c636af, 2016-04-14 (annotated)

Committer:
IanBenzMaxim
Date:
Thu Apr 14 19:48:01 2016 +0000
Revision:
1:e1c7c1c636af
Child:
6:b6bafd0a7013
Add initial source files.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
IanBenzMaxim 1:e1c7c1c636af 1 /*******************************************************************************
IanBenzMaxim 1:e1c7c1c636af 2 * Copyright (C) 2016 Maxim Integrated Products, Inc., All Rights Reserved.
IanBenzMaxim 1:e1c7c1c636af 3 *
IanBenzMaxim 1:e1c7c1c636af 4 * Permission is hereby granted, free of charge, to any person obtaining a
IanBenzMaxim 1:e1c7c1c636af 5 * copy of this software and associated documentation files (the "Software"),
IanBenzMaxim 1:e1c7c1c636af 6 * to deal in the Software without restriction, including without limitation
IanBenzMaxim 1:e1c7c1c636af 7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
IanBenzMaxim 1:e1c7c1c636af 8 * and/or sell copies of the Software, and to permit persons to whom the
IanBenzMaxim 1:e1c7c1c636af 9 * Software is furnished to do so, subject to the following conditions:
IanBenzMaxim 1:e1c7c1c636af 10 *
IanBenzMaxim 1:e1c7c1c636af 11 * The above copyright notice and this permission notice shall be included
IanBenzMaxim 1:e1c7c1c636af 12 * in all copies or substantial portions of the Software.
IanBenzMaxim 1:e1c7c1c636af 13 *
IanBenzMaxim 1:e1c7c1c636af 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
IanBenzMaxim 1:e1c7c1c636af 15 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
IanBenzMaxim 1:e1c7c1c636af 16 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IanBenzMaxim 1:e1c7c1c636af 17 * IN NO EVENT SHALL MAXIM INTEGRATED BE LIABLE FOR ANY CLAIM, DAMAGES
IanBenzMaxim 1:e1c7c1c636af 18 * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
IanBenzMaxim 1:e1c7c1c636af 19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
IanBenzMaxim 1:e1c7c1c636af 20 * OTHER DEALINGS IN THE SOFTWARE.
IanBenzMaxim 1:e1c7c1c636af 21 *
IanBenzMaxim 1:e1c7c1c636af 22 * Except as contained in this notice, the name of Maxim Integrated
IanBenzMaxim 1:e1c7c1c636af 23 * Products, Inc. shall not be used except as stated in the Maxim Integrated
IanBenzMaxim 1:e1c7c1c636af 24 * Products, Inc. Branding Policy.
IanBenzMaxim 1:e1c7c1c636af 25 *
IanBenzMaxim 1:e1c7c1c636af 26 * The mere transfer of this software does not imply any licenses
IanBenzMaxim 1:e1c7c1c636af 27 * of trade secrets, proprietary technology, copyrights, patents,
IanBenzMaxim 1:e1c7c1c636af 28 * trademarks, maskwork rights, or any other form of intellectual
IanBenzMaxim 1:e1c7c1c636af 29 * property whatsoever. Maxim Integrated Products, Inc. retains all
IanBenzMaxim 1:e1c7c1c636af 30 * ownership rights.
IanBenzMaxim 1:e1c7c1c636af 31 *******************************************************************************
IanBenzMaxim 1:e1c7c1c636af 32 */
IanBenzMaxim 1:e1c7c1c636af 33
IanBenzMaxim 1:e1c7c1c636af 34 #include "SensorNode.hpp"
IanBenzMaxim 1:e1c7c1c636af 35 #include "common.hpp"
IanBenzMaxim 1:e1c7c1c636af 36 #include "OneWire_Masters/DS2465/DS2465.hpp"
IanBenzMaxim 1:e1c7c1c636af 37 #include "mbed.h"
IanBenzMaxim 1:e1c7c1c636af 38
IanBenzMaxim 1:e1c7c1c636af 39 #ifdef TARGET_MAX32600
IanBenzMaxim 1:e1c7c1c636af 40 #include "max32600.h"
IanBenzMaxim 1:e1c7c1c636af 41 #include "clkman_regs.h"
IanBenzMaxim 1:e1c7c1c636af 42 #include "tpu_regs.h"
IanBenzMaxim 1:e1c7c1c636af 43 #else
IanBenzMaxim 1:e1c7c1c636af 44 #include <cstdlib>
IanBenzMaxim 1:e1c7c1c636af 45 #endif
IanBenzMaxim 1:e1c7c1c636af 46
IanBenzMaxim 1:e1c7c1c636af 47 bool SensorNode::rngInitialized = false;
IanBenzMaxim 1:e1c7c1c636af 48
IanBenzMaxim 1:e1c7c1c636af 49 void SensorNode::initializeRng()
IanBenzMaxim 1:e1c7c1c636af 50 {
IanBenzMaxim 1:e1c7c1c636af 51 #ifdef TARGET_MAX32600
IanBenzMaxim 1:e1c7c1c636af 52 MXC_CLKMAN->clk_config |= (MXC_F_CLKMAN_CLK_CONFIG_CRYPTO_ENABLE | MXC_F_CLKMAN_CLK_CONFIG_CRYPTO_RESET_N); // Enable crypto oscillator
IanBenzMaxim 1:e1c7c1c636af 53 while ((MXC_CLKMAN->intfl & MXC_F_CLKMAN_INTFL_CRYPTO_STABLE) != MXC_F_CLKMAN_INTFL_CRYPTO_STABLE) ; // Wait for crypto oscillator stability
IanBenzMaxim 1:e1c7c1c636af 54 MXC_CLKMAN->clk_ctrl |= MXC_F_CLKMAN_CLK_CTRL_CRYPTO_GATE_N; // Disable crypto clock gating
IanBenzMaxim 1:e1c7c1c636af 55 MXC_CLKMAN->crypt_clk_ctrl_2_prng = MXC_CLKMAN->clk_ctrl_10_prng = 1; // Set PRNG clock to crypto clock
IanBenzMaxim 1:e1c7c1c636af 56 MXC_CLKMAN->clk_gate_ctrl2 |= (1 << MXC_F_CLKMAN_CLK_GATE_CTRL2_TPU_CLK_GATER_POS); // Use dynamic clock gating
IanBenzMaxim 1:e1c7c1c636af 57 #endif
IanBenzMaxim 1:e1c7c1c636af 58 }
IanBenzMaxim 1:e1c7c1c636af 59
IanBenzMaxim 1:e1c7c1c636af 60 SensorNode::SensorNode(I2C & i2c, std::uint8_t ds7505_i2c_addr, std::uint8_t max44009_i2c_addr, DS2465 & ds2465)
IanBenzMaxim 1:e1c7c1c636af 61 : m_initialLux(1), ds28e15_22_25(ds2465), ds7505(i2c, ds7505_i2c_addr), max44009(i2c, max44009_i2c_addr), ds2465(ds2465)
IanBenzMaxim 1:e1c7c1c636af 62 {
IanBenzMaxim 1:e1c7c1c636af 63 if (!rngInitialized)
IanBenzMaxim 1:e1c7c1c636af 64 {
IanBenzMaxim 1:e1c7c1c636af 65 initializeRng();
IanBenzMaxim 1:e1c7c1c636af 66 rngInitialized = true;
IanBenzMaxim 1:e1c7c1c636af 67 }
IanBenzMaxim 1:e1c7c1c636af 68 }
IanBenzMaxim 1:e1c7c1c636af 69
IanBenzMaxim 1:e1c7c1c636af 70 bool SensorNode::initializeSensors()
IanBenzMaxim 1:e1c7c1c636af 71 {
IanBenzMaxim 1:e1c7c1c636af 72 return (max44009.read_current_lux(m_initialLux) == MAX44009::Success);
IanBenzMaxim 1:e1c7c1c636af 73 }
IanBenzMaxim 1:e1c7c1c636af 74
IanBenzMaxim 1:e1c7c1c636af 75 bool SensorNode::setSecret()
IanBenzMaxim 1:e1c7c1c636af 76 {
IanBenzMaxim 1:e1c7c1c636af 77 DS28E15_22_25::Scratchpad scratchpad;
IanBenzMaxim 1:e1c7c1c636af 78 DS28E15_22_25::Page pageData;
IanBenzMaxim 1:e1c7c1c636af 79
IanBenzMaxim 1:e1c7c1c636af 80 // Create constant partial secret
IanBenzMaxim 1:e1c7c1c636af 81 std::memset(scratchpad, defaultPaddingByte, scratchpad.length);
IanBenzMaxim 1:e1c7c1c636af 82 // Read page data
IanBenzMaxim 1:e1c7c1c636af 83 bool result = (ds2465.readMemory(DS2465::ADDR_USER_MEM_PAGE_0, pageData, pageData.length, false) == OneWireMaster::Success);
IanBenzMaxim 1:e1c7c1c636af 84 // Calculate secret
IanBenzMaxim 1:e1c7c1c636af 85 if (result)
IanBenzMaxim 1:e1c7c1c636af 86 {
IanBenzMaxim 1:e1c7c1c636af 87 result = (DS28E15_22_25::computeNextSecret(ds2465, pageData, authData.pageNum, scratchpad, ds28e15_22_25.romId, ds28e15_22_25.manId) == ISha256MacCoprocessor::Success);
IanBenzMaxim 1:e1c7c1c636af 88 }
IanBenzMaxim 1:e1c7c1c636af 89 return result;
IanBenzMaxim 1:e1c7c1c636af 90 }
IanBenzMaxim 1:e1c7c1c636af 91
IanBenzMaxim 1:e1c7c1c636af 92 bool SensorNode::checkProvisioned(bool & provisioned)
IanBenzMaxim 1:e1c7c1c636af 93 {
IanBenzMaxim 1:e1c7c1c636af 94 DS28E15_22_25::BlockProtection protectionStatus;
IanBenzMaxim 1:e1c7c1c636af 95 bool result;
IanBenzMaxim 1:e1c7c1c636af 96
IanBenzMaxim 1:e1c7c1c636af 97 // Select device through Skip ROM
IanBenzMaxim 1:e1c7c1c636af 98 result = (ds2465.OWSkipROM() == OneWireMaster::Success);
IanBenzMaxim 1:e1c7c1c636af 99 if (result)
IanBenzMaxim 1:e1c7c1c636af 100 result = (ds28e15_22_25.readBlockProtection(0, protectionStatus) == OneWireSlave::Success);
IanBenzMaxim 1:e1c7c1c636af 101 if (result)
IanBenzMaxim 1:e1c7c1c636af 102 {
IanBenzMaxim 1:e1c7c1c636af 103 if (!protectionStatus.noProtection())
IanBenzMaxim 1:e1c7c1c636af 104 {
IanBenzMaxim 1:e1c7c1c636af 105 // Select device through Skip ROM
IanBenzMaxim 1:e1c7c1c636af 106 result = (ds2465.OWSkipROM() == OneWireMaster::Success);
IanBenzMaxim 1:e1c7c1c636af 107 if (result)
IanBenzMaxim 1:e1c7c1c636af 108 result = (ds28e15_22_25.readSegment(authData.pageNum, authData.segmentNum, authData.segment) == OneWireSlave::Success);
IanBenzMaxim 1:e1c7c1c636af 109 if (result)
IanBenzMaxim 1:e1c7c1c636af 110 provisioned = true;
IanBenzMaxim 1:e1c7c1c636af 111 }
IanBenzMaxim 1:e1c7c1c636af 112 else
IanBenzMaxim 1:e1c7c1c636af 113 {
IanBenzMaxim 1:e1c7c1c636af 114 provisioned = false;
IanBenzMaxim 1:e1c7c1c636af 115 }
IanBenzMaxim 1:e1c7c1c636af 116 }
IanBenzMaxim 1:e1c7c1c636af 117 return result;
IanBenzMaxim 1:e1c7c1c636af 118 }
IanBenzMaxim 1:e1c7c1c636af 119
IanBenzMaxim 1:e1c7c1c636af 120 bool SensorNode::checkAuthentic(unsigned int userEntropy)
IanBenzMaxim 1:e1c7c1c636af 121 {
IanBenzMaxim 1:e1c7c1c636af 122 DS28E15_22_25::Scratchpad challenge;
IanBenzMaxim 1:e1c7c1c636af 123 DS28E15_22_25::Page pageData;
IanBenzMaxim 1:e1c7c1c636af 124
IanBenzMaxim 1:e1c7c1c636af 125 // Select device through Skip ROM
IanBenzMaxim 1:e1c7c1c636af 126 if (ds2465.OWSkipROM() != OneWireMaster::Success)
IanBenzMaxim 1:e1c7c1c636af 127 return false;
IanBenzMaxim 1:e1c7c1c636af 128 // Read page data
IanBenzMaxim 1:e1c7c1c636af 129 if (ds28e15_22_25.readPage(authData.pageNum, pageData, false) != OneWireSlave::Success)
IanBenzMaxim 1:e1c7c1c636af 130 return false;
IanBenzMaxim 1:e1c7c1c636af 131
IanBenzMaxim 1:e1c7c1c636af 132 // Create random challenge
IanBenzMaxim 1:e1c7c1c636af 133 // Use hardare RNG on MAX32600
IanBenzMaxim 1:e1c7c1c636af 134 #ifdef TARGET_MAX32600
IanBenzMaxim 1:e1c7c1c636af 135 MXC_TPU->prng_user_entropy = userEntropy;
IanBenzMaxim 1:e1c7c1c636af 136 #else
IanBenzMaxim 1:e1c7c1c636af 137 std::srand(userEntropy);
IanBenzMaxim 1:e1c7c1c636af 138 #endif
IanBenzMaxim 1:e1c7c1c636af 139 for (std::size_t i = 0; i < challenge.length; i++)
IanBenzMaxim 1:e1c7c1c636af 140 {
IanBenzMaxim 1:e1c7c1c636af 141 #ifdef TARGET_MAX32600
IanBenzMaxim 1:e1c7c1c636af 142 challenge[i] = MXC_TPU->prng_rnd_num;
IanBenzMaxim 1:e1c7c1c636af 143 #else
IanBenzMaxim 1:e1c7c1c636af 144 challenge[i] = std::rand();
IanBenzMaxim 1:e1c7c1c636af 145 #endif
IanBenzMaxim 1:e1c7c1c636af 146 }
IanBenzMaxim 1:e1c7c1c636af 147
IanBenzMaxim 1:e1c7c1c636af 148 // Select device through Skip ROM
IanBenzMaxim 1:e1c7c1c636af 149 if (ds2465.OWSkipROM() != OneWireMaster::Success)
IanBenzMaxim 1:e1c7c1c636af 150 return false;
IanBenzMaxim 1:e1c7c1c636af 151 // Write challenge to scratchpad
IanBenzMaxim 1:e1c7c1c636af 152 if (ds28e15_22_25.writeScratchpad(challenge) != OneWireSlave::Success)
IanBenzMaxim 1:e1c7c1c636af 153 return false;
IanBenzMaxim 1:e1c7c1c636af 154 // Select device through Skip ROM
IanBenzMaxim 1:e1c7c1c636af 155 if (ds2465.OWSkipROM() != OneWireMaster::Success)
IanBenzMaxim 1:e1c7c1c636af 156 return false;
IanBenzMaxim 1:e1c7c1c636af 157 // Have device compute MAC
IanBenzMaxim 1:e1c7c1c636af 158 DS28E15_22_25::Mac nodeMac;
IanBenzMaxim 1:e1c7c1c636af 159 if (ds28e15_22_25.computeReadPageMac(0, false, nodeMac) != OneWireSlave::Success)
IanBenzMaxim 1:e1c7c1c636af 160 return false;
IanBenzMaxim 1:e1c7c1c636af 161 // Compute expected MAC
IanBenzMaxim 1:e1c7c1c636af 162 DS28E15_22_25::Mac controllerMac;
IanBenzMaxim 1:e1c7c1c636af 163 if (DS28E15_22_25::computeAuthMac(ds2465, pageData, authData.pageNum, challenge, ds28e15_22_25.romId, ds28e15_22_25.manId, controllerMac) != ISha256MacCoprocessor::Success)
IanBenzMaxim 1:e1c7c1c636af 164 return false;
IanBenzMaxim 1:e1c7c1c636af 165 // Check if authentic
IanBenzMaxim 1:e1c7c1c636af 166 return (nodeMac == controllerMac);
IanBenzMaxim 1:e1c7c1c636af 167 }
IanBenzMaxim 1:e1c7c1c636af 168
IanBenzMaxim 1:e1c7c1c636af 169 bool SensorNode::readSensorData(SensorData & sensorData)
IanBenzMaxim 1:e1c7c1c636af 170 {
IanBenzMaxim 1:e1c7c1c636af 171 bool result;
IanBenzMaxim 1:e1c7c1c636af 172 std::int8_t temp;
IanBenzMaxim 1:e1c7c1c636af 173
IanBenzMaxim 1:e1c7c1c636af 174 // Read temperature sensor
IanBenzMaxim 1:e1c7c1c636af 175 result = (ds7505.read_current_temp(temp) == DS7505::Success);
IanBenzMaxim 1:e1c7c1c636af 176
IanBenzMaxim 1:e1c7c1c636af 177 if (result)
IanBenzMaxim 1:e1c7c1c636af 178 {
IanBenzMaxim 1:e1c7c1c636af 179 sensorData.temp = temp;
IanBenzMaxim 1:e1c7c1c636af 180
IanBenzMaxim 1:e1c7c1c636af 181 // Read light sensor
IanBenzMaxim 1:e1c7c1c636af 182 double currentLux;
IanBenzMaxim 1:e1c7c1c636af 183 result = (max44009.read_current_lux(currentLux) == MAX44009::Success);
IanBenzMaxim 1:e1c7c1c636af 184 if (result)
IanBenzMaxim 1:e1c7c1c636af 185 {
IanBenzMaxim 1:e1c7c1c636af 186 // Convert lux to remaining filter life
IanBenzMaxim 1:e1c7c1c636af 187 sensorData.filterLife = (unsigned int)((currentLux / m_initialLux) * 100);
IanBenzMaxim 1:e1c7c1c636af 188 }
IanBenzMaxim 1:e1c7c1c636af 189 }
IanBenzMaxim 1:e1c7c1c636af 190
IanBenzMaxim 1:e1c7c1c636af 191 return result;
IanBenzMaxim 1:e1c7c1c636af 192 }
IanBenzMaxim 1:e1c7c1c636af 193
IanBenzMaxim 1:e1c7c1c636af 194 bool SensorNode::checkAndWriteAuthData(SensorData & sensorData)
IanBenzMaxim 1:e1c7c1c636af 195 {
IanBenzMaxim 1:e1c7c1c636af 196 bool result = true;
IanBenzMaxim 1:e1c7c1c636af 197
IanBenzMaxim 1:e1c7c1c636af 198 if (sensorData.filterLife > authData.filterLife)
IanBenzMaxim 1:e1c7c1c636af 199 {
IanBenzMaxim 1:e1c7c1c636af 200 sensorData.filterLife = authData.filterLife;
IanBenzMaxim 1:e1c7c1c636af 201 }
IanBenzMaxim 1:e1c7c1c636af 202 else if (sensorData.filterLife < authData.filterLife)
IanBenzMaxim 1:e1c7c1c636af 203 {
IanBenzMaxim 1:e1c7c1c636af 204 AuthData oldAuthData(authData);
IanBenzMaxim 1:e1c7c1c636af 205 authData.filterLife = sensorData.filterLife;
IanBenzMaxim 1:e1c7c1c636af 206 // Select device through Skip ROM
IanBenzMaxim 1:e1c7c1c636af 207 result = (ds2465.OWSkipROM() == OneWireMaster::Success);
IanBenzMaxim 1:e1c7c1c636af 208 // Write new filter life to DS28E15
IanBenzMaxim 1:e1c7c1c636af 209 if (result)
IanBenzMaxim 1:e1c7c1c636af 210 result = (ds28e15_22_25.writeAuthSegment(ds2465, authData.pageNum, authData.segmentNum, authData.segment, oldAuthData.segment, false) == OneWireSlave::Success);
IanBenzMaxim 1:e1c7c1c636af 211 }
IanBenzMaxim 1:e1c7c1c636af 212
IanBenzMaxim 1:e1c7c1c636af 213 return result;
IanBenzMaxim 1:e1c7c1c636af 214 }
IanBenzMaxim 1:e1c7c1c636af 215
IanBenzMaxim 1:e1c7c1c636af 216 SensorNode::State SensorNode::detect(unsigned int userEntropy)
IanBenzMaxim 1:e1c7c1c636af 217 {
IanBenzMaxim 1:e1c7c1c636af 218 bool provisioned;
IanBenzMaxim 1:e1c7c1c636af 219
IanBenzMaxim 1:e1c7c1c636af 220 ds2465.OWSetSpeed(DS2465::SPEED_OVERDRIVE);
IanBenzMaxim 1:e1c7c1c636af 221
IanBenzMaxim 1:e1c7c1c636af 222 if (ds2465.OWReadROM(ds28e15_22_25.romId) != OneWireMaster::Success)
IanBenzMaxim 1:e1c7c1c636af 223 return UnableToCommunicate;
IanBenzMaxim 1:e1c7c1c636af 224
IanBenzMaxim 1:e1c7c1c636af 225 if (!checkProvisioned(provisioned))
IanBenzMaxim 1:e1c7c1c636af 226 return UnableToCommunicate;
IanBenzMaxim 1:e1c7c1c636af 227
IanBenzMaxim 1:e1c7c1c636af 228 if (!provisioned)
IanBenzMaxim 1:e1c7c1c636af 229 return NotProvisioned;
IanBenzMaxim 1:e1c7c1c636af 230
IanBenzMaxim 1:e1c7c1c636af 231 if (!setSecret())
IanBenzMaxim 1:e1c7c1c636af 232 return UnableToCommunicate;
IanBenzMaxim 1:e1c7c1c636af 233
IanBenzMaxim 1:e1c7c1c636af 234 if (!checkAuthentic(userEntropy))
IanBenzMaxim 1:e1c7c1c636af 235 return NotAuthentic;
IanBenzMaxim 1:e1c7c1c636af 236
IanBenzMaxim 1:e1c7c1c636af 237 if (!initializeSensors())
IanBenzMaxim 1:e1c7c1c636af 238 return UnableToCommunicate;
IanBenzMaxim 1:e1c7c1c636af 239
IanBenzMaxim 1:e1c7c1c636af 240 return Authentic;
IanBenzMaxim 1:e1c7c1c636af 241 }
IanBenzMaxim 1:e1c7c1c636af 242
IanBenzMaxim 1:e1c7c1c636af 243 SensorNode::State SensorNode::authenticatedReadSensorData(unsigned int userEntropy, SensorData & sensorData)
IanBenzMaxim 1:e1c7c1c636af 244 {
IanBenzMaxim 1:e1c7c1c636af 245 ds2465.OWSetSpeed(DS2465::SPEED_OVERDRIVE);
IanBenzMaxim 1:e1c7c1c636af 246
IanBenzMaxim 1:e1c7c1c636af 247 if (!setSecret())
IanBenzMaxim 1:e1c7c1c636af 248 return UnableToCommunicate;
IanBenzMaxim 1:e1c7c1c636af 249
IanBenzMaxim 1:e1c7c1c636af 250 if (!checkAuthentic(userEntropy))
IanBenzMaxim 1:e1c7c1c636af 251 return NotAuthentic;
IanBenzMaxim 1:e1c7c1c636af 252
IanBenzMaxim 1:e1c7c1c636af 253 if (!readSensorData(sensorData))
IanBenzMaxim 1:e1c7c1c636af 254 return UnableToCommunicate;
IanBenzMaxim 1:e1c7c1c636af 255
IanBenzMaxim 1:e1c7c1c636af 256 if (!checkAndWriteAuthData(sensorData))
IanBenzMaxim 1:e1c7c1c636af 257 return NotAuthentic;
IanBenzMaxim 1:e1c7c1c636af 258
IanBenzMaxim 1:e1c7c1c636af 259 return Authentic;
IanBenzMaxim 1:e1c7c1c636af 260 }