Maxim Integrated / Mbed OS MAXREFDES155#

DeepCover Embedded Security in IoT: Public-key Secured Data Paths

Dependencies:   MaximInterface

The MAXREFDES155# is an internet-of-things (IoT) embedded-security reference design, built to authenticate and control a sensing node using elliptic-curve-based public-key cryptography with control and notification from a web server.

The hardware includes an ARM® mbed™ shield and attached sensor endpoint. The shield contains a DS2476 DeepCover® ECDSA/SHA-2 coprocessor, Wifi communication, LCD push-button controls, and status LEDs. The sensor endpoint is attached to the shield using a 300mm cable and contains a DS28C36 DeepCover ECDSA/SHA-2 authenticator, IR-thermal sensor, and aiming laser for the IR sensor. The MAXREFDES155# is equipped with a standard Arduino® form-factor shield connector for immediate testing using an mbed board such as the MAX32600MBED#. The combination of these two devices represent an IoT device. Communication to the web server is accomplished with the shield Wifi circuitry. Communication from the shield to the attached sensor module is accomplished over I2C . The sensor module represents an IoT endpoint that generates small data with a requirement for message authenticity/integrity and secure on/off operational control.

The design is hierarchical with each mbed platform and shield communicating data from the sensor node to a web server that maintains a centralized log and dispatches notifications as necessary. The simplicity of this design enables rapid integration into any star-topology IoT network to provide security with the low overhead and cost provided by the ECDSA-P256 asymmetric-key and SHA-256 symmetric-key algorithms.

More information about the MAXREFDES155# is available on the Maxim Integrated website.

Diff: Button.cpp

Revision:
13:6a6225690c2e
Parent:
10:71359af61af8
--- a/Button.cpp	Thu Jun 01 14:21:58 2017 -0500
+++ b/Button.cpp	Mon Nov 06 18:12:27 2017 -0600
@@ -32,46 +32,44 @@
 
 #include "Button.hpp"
 
-static const int deselectedBorderWidth = 1; // Border width when button is deselected.
-static const int selectedBorderWidth = 2; // Border width when button is selected.
-static const int borderPadding = selectedBorderWidth + 1; // Total width of the border region.
+// Border width when button is deselected.
+static const int deselectedBorderWidth = 1;
+// Border width when button is selected.
+static const int selectedBorderWidth = 2;
+// Total width of the border region.
+static const int borderPadding = selectedBorderWidth + 1;
 
-Button::Button()
-{
-    m_border.setParent(this);
-    m_border.setBorderWidth(deselectedBorderWidth);
-    m_label.setParent(this);
-}
-    
-int Button::preferredWidth() const
-{
-    return m_label.preferredWidth() + 2 * borderPadding;
+Button::Button() {
+  m_border.setParent(this);
+  m_border.setBorderWidth(deselectedBorderWidth);
+  m_label.setParent(this);
 }
 
-int Button::preferredHeight() const
-{
-    return m_label.preferredHeight() + 2 * borderPadding;
+int Button::preferredWidth() const {
+  return m_label.preferredWidth() + 2 * borderPadding;
+}
+
+int Button::preferredHeight() const {
+  return m_label.preferredHeight() + 2 * borderPadding;
 }
 
-void Button::focusChanged(bool focused)
-{
-    m_border.setBorderWidth(focused ? selectedBorderWidth : deselectedBorderWidth);
-    invalidate(); // Ensure border and text are redrawn together.
+void Button::focusChanged(bool focused) {
+  m_border.setBorderWidth(focused ? selectedBorderWidth
+                                  : deselectedBorderWidth);
+  invalidate(); // Ensure border and text are redrawn together.
 }
 
-void Button::resized()
-{
-    m_border.resize(width(), height());
-    m_label.move(borderPadding, borderPadding);
-    m_label.resize(m_border.width() - 2 * borderPadding, m_border.height() - 2 * borderPadding);
+void Button::resized() {
+  m_border.resize(width(), height());
+  m_label.move(borderPadding, borderPadding);
+  m_label.resize(m_border.width() - 2 * borderPadding,
+                 m_border.height() - 2 * borderPadding);
 }
 
-bool Button::doProcessKey(Key key)
-{
-    bool handled = (key == LeftClickKey);
-    if (handled && m_clickedHandler)
-    {
-        m_clickedHandler();
-    }
-    return handled;
+bool Button::doProcessKey(Key key) {
+  bool handled = (key == LeftClickKey);
+  if (handled && m_clickedHandler) {
+    m_clickedHandler(this);
+  }
+  return handled;
 }