Course update: lessons, CTF 0x0011a_cb, and documentation

- 0x0011a_cb (Operation Dark Vector): nation-state CTF redesign with an
  AES-128-ECB sealed target and a plaintext launch origin; RP2350 firmware with
  bearing-driven servo, tri-color LEDs, GSV stats, and a realistic no-fix path
- docs: story-driven classified brief, GDB and Ghidra tutorials with deep
  step-throughs, regenerated artifacts and PDFs
- scripts: docstring standard, AES per-student randomizer, telemetry monitor
- week 3 to week 5 lessons: Ghidra patching tutorial, CMSIS-SVD hardware RE,
  double floating-point and GPIO architecture chapters, README structure

0x0011a_cb/src/navigation.c

@@ -0,0 +1,106 @@
+// MIT License
+//
+// Copyright (c) 2026 Kevin Thomas
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+//
+// Author:  Kevin Thomas
+// Email:   kevin@mytechnotalent.com
+// GitHub:  https://github.com/mytechnotalent
+// File:    navigation.c
+// Desc:    Implements waypoint navigation, dead-reckoning, and telemetry dispatch.
+// Created: 2026
+
+#include "navigation.h"
+#include "ctf_target.h"
+#include "aes.h"
+#include "lora.h"
+#include "payload.h"
+#include "propeller.h"
+#include <stdio.h>
+#include <math.h>
+#include <string.h>
+#include <stdint.h>
+
+double TARGET_LAT = 0.0;
+double TARGET_LON = 0.0;
+
+const double ORIGIN_LAT = 38.840280;
+const double ORIGIN_LON = -77.428890;
+
+void init_navigation(void)
+{
+    uint8_t pt[16];
+    const uint8_t key[16] = CTF_AES_KEY;
+    const uint8_t ct[16] = CTF_TARGET_CT;
+    aes128_ecb_decrypt_block(ct, key, pt);
+    memcpy(&TARGET_LAT, pt, sizeof(double));
+    memcpy(&TARGET_LON, pt + 8, sizeof(double));
+}
+
+void send_telemetry(double cur_lat, double cur_lon)
+{
+    char msg[80];
+    snprintf(msg, sizeof(msg), "CURRENT LAT: %lf, LON: %lf\r\n", cur_lat, cur_lon);
+    printf("%s", msg);
+    lora_send(msg);
+}
+
+void dead_reckon_step(double *cur_lat, double *cur_lon)
+{
+    double dlat = TARGET_LAT - *cur_lat;
+    double dlon = TARGET_LON - *cur_lon;
+    *cur_lat += (fabs(dlat) < 0.005) ? dlat : ((dlat > 0.0) ? 0.004166 : -0.004166);
+    *cur_lon += (fabs(dlon) < 0.005) ? dlon : ((dlon > 0.0) ? 0.002139 : -0.002139);
+}
+
+bool check_arrival(double cur_lat, double cur_lon)
+{
+    return (cur_lat == TARGET_LAT) && (cur_lon == TARGET_LON);
+}
+
+/**
+ * @brief Compute the initial bearing from one point toward another.
+ *
+ * @param lat1 Origin latitude in degrees.
+ * @param lon1 Origin longitude in degrees.
+ * @param lat2 Destination latitude in degrees.
+ * @param lon2 Destination longitude in degrees.
+ * @return double Bearing in degrees (0 to 360).
+ */
+static double bearing_to(double lat1, double lon1, double lat2, double lon2)
+{
+    double p1 = lat1 * 0.017453292519943295, p2 = lat2 * 0.017453292519943295;
+    double dl = (lon2 - lon1) * 0.017453292519943295;
+    double y = sin(dl) * cos(p2);
+    double x = cos(p1) * sin(p2) - sin(p1) * cos(p2) * cos(dl);
+    double b = atan2(y, x) * 57.29577951308232;
+    return (b < 0.0) ? (b + 360.0) : b;
+}
+
+void navigate_to_target(double cur_lat, double cur_lon)
+{
+    send_telemetry(cur_lat, cur_lon);
+    if (check_arrival(cur_lat, cur_lon)) {
+        propeller_stop();
+        release_payload();
+    } else {
+        propeller_set_bearing(bearing_to(cur_lat, cur_lon, TARGET_LAT, TARGET_LON));
+    }
+}