Add EthernetMQTT example to demonstrate mTLS (credit @Atalonica)

examples/EthernetMQTT/EthernetMQTT.ino

@@ -0,0 +1,87 @@
+/*
+ Basic MQTT example (with SSL!)
+ This sketch demonstrates the basic capabilities of the library.
+ It connects to an MQTT server then:
+  - publishes "hello world" to the topic "outTopic"
+  - subscribes to the topic "inTopic", printing out any messages
+    it receives. NB - it assumes the received payloads are strings not binary
+ It will reconnect to the server if the connection is lost using a blocking
+ reconnect function. See the 'mqtt_reconnect_nonblocking' example for how to
+ achieve the same result without blocking the main loop.
+
+ You will need to populate "certificates.h" with your trust anchors
+ (see https://github.com/OPEnSLab-OSU/SSLClient/blob/master/TrustAnchors.md)
+ and my_cert/my_key with your certificate/private key pair
+ (see https://github.com/OPEnSLab-OSU/SSLClient#mtls).
+*/
+#include <SPI.h>
+#include <EthernetLarge.h>
+#include <SSLClient.h>
+#include "certificates.h" // This file must be regenerated
+#include <PubSubClient.h>
+
+const char my_cert[] = "FIXME";
+const char my_key[] = "FIXME";
+SSLClientParameters mTLS = SSLClientParameters::fromPEM(my_cert, sizeof my_cert, my_key, sizeof my_key);
+
+byte mac[] = {  0xDE, 0xED, 0xBA, 0xFE, 0xFE, 0xED };
+const char* mqttServer = "broker.example"; // Broker address
+IPAddress ip (192, 168, 1, 2); // Custom client static IP
+
+void callback(char* topic, byte* payload, unsigned int length) {
+  Serial.print("Message arrived [");
+  Serial.print(topic);
+  Serial.print("] ");
+  for (int i=0;i<length;i++) {
+    Serial.print((char)payload[i]);
+  }
+  Serial.println();
+}
+
+EthernetClient ethClient;
+SSLClient ethClientSSL(ethClient, TAs, (size_t)TAs_NUM, A5);
+PubSubClient client(mqttServer, 8883, callback, ethClientSSL);
+
+void reconnect() {
+  // Loop until we're reconnected
+  while (!client.connected()) {
+    Serial.print("Attempting MQTT connection...");
+    // Attempt to connect
+    if (client.connect("arduinoClient")) {
+      Serial.println("connected");
+      // Once connected, publish an announcement...
+      client.publish("outTopic","hello world");
+      // ... and resubscribe
+      client.subscribe("inTopic");
+    } else {
+      Serial.print("failed, rc=");
+      Serial.print(client.state());
+      Serial.println(" try again in 5 seconds");
+      // Wait 5 seconds before retrying
+      delay(5000);
+    }
+  }
+}
+
+void setup(){
+  // Start Serial
+  Serial.begin(115200);
+  while(!Serial);
+  // Enable mutual TLS with SSLClient
+  ethClientSSL.setMutualAuthParams(mTLS);
+  // You can use Ethernet.init(pin) to configure the CS pin
+  Ethernet.init(10);  // Most Arduino shields
+  //Ethernet.init(5);   // MKR ETH shield
+  //Ethernet.init(0);   // Teensy 2.0
+  //Ethernet.init(20);  // Teensy++ 2.0
+  //Ethernet.init(15);  // ESP8266 with Adafruit Featherwing Ethernet
+  //Ethernet.init(33);  // ESP32 with Adafruit Featherwing Ethernet
+  Ethernet.begin(mac, ip);
+}
+
+void loop(){
+  if (!client.connected()) {
+    reconnect();
+  }
+  client.loop();
+}

tools/pycert_bearssl/certificates.h

@@ -0,0 +1,75 @@
+#ifndef _CERTIFICATES_H_
+#define _CERTIFICATES_H_
+
+#ifdef __cplusplus
+extern "C"
+{
+#endif
+
+/* This file is auto-generated by the pycert_bearssl tool.  Do not change it manually.
+ * Certificates are BearSSL br_x509_trust_anchor format.  Included certs:
+ *
+ * Index:    0
+ * Label:    OPEnS
+ * Subject:  C=US,ST=OR,L=Corvallis,O=OPEnS
+ */
+
+#define TAs_NUM 1
+
+static const unsigned char TA_DN0[] = {
+    0x30, 0x3e, 0x31, 0x0b, 0x30, 0x09, 0x06, 0x03, 0x55, 0x04, 0x06, 0x13,
+    0x02, 0x55, 0x53, 0x31, 0x0b, 0x30, 0x09, 0x06, 0x03, 0x55, 0x04, 0x08,
+    0x0c, 0x02, 0x4f, 0x52, 0x31, 0x12, 0x30, 0x10, 0x06, 0x03, 0x55, 0x04,
+    0x07, 0x0c, 0x09, 0x43, 0x6f, 0x72, 0x76, 0x61, 0x6c, 0x6c, 0x69, 0x73,
+    0x31, 0x0e, 0x30, 0x0c, 0x06, 0x03, 0x55, 0x04, 0x0a, 0x0c, 0x05, 0x4f,
+    0x50, 0x45, 0x6e, 0x53,
+};
+
+static const unsigned char TA_RSA_N0[] = {
+    0xe2, 0x80, 0x32, 0x18, 0xe7, 0xa6, 0x94, 0x04, 0x62, 0x43, 0xbc, 0x1e,
+    0x14, 0x13, 0xaf, 0x40, 0x82, 0x0e, 0x14, 0x57, 0xe8, 0x50, 0x98, 0x38,
+    0xa4, 0xd9, 0xf1, 0x8a, 0x20, 0x5f, 0x37, 0xae, 0xd1, 0xdf, 0xc1, 0xc0,
+    0x53, 0x47, 0xd2, 0x4b, 0x10, 0x63, 0xe8, 0x8f, 0xb5, 0x58, 0x9f, 0xd8,
+    0x69, 0x86, 0x31, 0xbc, 0x9f, 0x39, 0xf5, 0x88, 0xb3, 0xae, 0xcb, 0x25,
+    0x50, 0xc0, 0x47, 0x7c, 0xde, 0x68, 0xdc, 0x5c, 0xb6, 0x68, 0xef, 0x17,
+    0xe3, 0xf1, 0xd9, 0x41, 0xb1, 0x8a, 0xde, 0x31, 0x74, 0x82, 0xa9, 0x14,
+    0x4b, 0x12, 0x7d, 0x7a, 0xbc, 0x2a, 0x8e, 0x6c, 0xf6, 0xfc, 0xeb, 0xda,
+    0xe3, 0x55, 0x11, 0x77, 0x98, 0x71, 0xe6, 0xa7, 0x0d, 0x9a, 0x10, 0x47,
+    0xe9, 0xde, 0x38, 0x71, 0x68, 0xe6, 0xbc, 0x8a, 0xec, 0xdd, 0xac, 0x53,
+    0xdf, 0x20, 0x13, 0x55, 0x59, 0x70, 0xf1, 0xd5, 0x38, 0xc0, 0x4b, 0x46,
+    0x3b, 0xe4, 0x82, 0x56, 0x27, 0x36, 0xaf, 0x4e, 0x80, 0x4d, 0xc4, 0xbc,
+    0x21, 0x4c, 0x20, 0xc8, 0x4e, 0x87, 0x7d, 0x6c, 0x6f, 0xa2, 0x7b, 0x61,
+    0xf1, 0x0b, 0xdc, 0xaa, 0x0c, 0xbb, 0x95, 0xdd, 0xe0, 0x1b, 0x92, 0x29,
+    0x96, 0xf8, 0xf3, 0x5e, 0x47, 0x5b, 0x88, 0xe3, 0x8e, 0xb0, 0x4b, 0x89,
+    0xaf, 0x73, 0x55, 0x08, 0x7d, 0xcc, 0xdf, 0x84, 0x7e, 0xaf, 0xba, 0x7c,
+    0xdd, 0x6e, 0x5c, 0xc7, 0xd8, 0x2b, 0x25, 0x35, 0xdb, 0x2e, 0x53, 0x90,
+    0xd1, 0x46, 0x20, 0x77, 0x5a, 0x39, 0xed, 0x5f, 0xcd, 0xee, 0x12, 0xe4,
+    0x12, 0xdf, 0xaa, 0xa3, 0x18, 0x82, 0x69, 0x31, 0xc6, 0x0c, 0x7b, 0xa4,
+    0x5b, 0x11, 0x9a, 0xd5, 0x0e, 0x21, 0x7d, 0x68, 0xc0, 0x5b, 0x2a, 0xb4,
+    0xb5, 0x89, 0x18, 0x7d, 0x01, 0x27, 0xa7, 0x2e, 0x60, 0x0a, 0xc4, 0x58,
+    0xca, 0x8e, 0x26, 0x03,
+};
+
+static const unsigned char TA_RSA_E0[] = {
+    0x01, 0x00, 0x01,
+};
+
+static const br_x509_trust_anchor TAs[] = {
+    {
+        { (unsigned char *)TA_DN0, sizeof TA_DN0 },
+        BR_X509_TA_CA,
+        {
+            BR_KEYTYPE_RSA,
+            { .rsa = {
+                (unsigned char *)TA_RSA_N0, sizeof TA_RSA_N0,
+                (unsigned char *)TA_RSA_E0, sizeof TA_RSA_E0,
+            } }
+        }
+    },
+};
+
+#ifdef __cplusplus
+} /* extern "C" */
+#endif
+
+#endif /* ifndef _CERTIFICATES_H_ */