Add encryption support

Author: multiplemonomials

SimpleApp.cpp

@@ -37,6 +37,9 @@ int main()
             tr_info("Regular boot");
             break;
 
+        // Note: Older mcuboot versions appear to use SWAP_TYPE_REVERT.
+        // Newer ones seem to use SWAP_TYPE_TEST.
+        case BOOT_SWAP_TYPE_TEST:
         case BOOT_SWAP_TYPE_REVERT:
             // After MCUboot has swapped a (non-permanent) update image
             // into the primary slot, it defaults to reverting the image on the NEXT boot.
@@ -69,7 +72,6 @@ int main()
             // should never reach the application...
         case BOOT_SWAP_TYPE_FAIL:   // Unable to boot due to invalid image
         case BOOT_SWAP_TYPE_PERM:   // Permanent update requested (when signing the image) and to be performed
-        case BOOT_SWAP_TYPE_TEST:   // Revertable update requested and to be performed
         case BOOT_SWAP_TYPE_PANIC:  // Unrecoverable error
         default:
             tr_error("Unexpected swap type: %d", swap_type);

mbed_app.json5

@@ -11,12 +11,20 @@
             "required": false
         },
     },
+
+    "macros": [
+        "MBEDTLS_CIPHER_MODE_CTR"
+    ],
+
     "target_overrides": {
         "*": {
             "mcuboot.bootloader-build": 0,
             "target.c_lib": "small",
             "mcuboot.log-level": "MCUBOOT_LOG_LEVEL_DEBUG",
-            "mbed-trace.enable": true
+            "mbed-trace.enable": true,
+
+            // Change to true to enable encryption of the image
+            "mcuboot.encrypt-rsa": false
         },
 //         "NRF52840_DK": {
 //             "demo-button-active-low": true,