add support for multiple TOTP keys

movement/watch_faces/complication/totp_face.c

@@ -1,7 +1,3 @@
-/**
- * TODO:
- * - Support for multiple codes
- */
 #include <stdlib.h>
 #include <string.h>
 #include "totp_face.h"
@@ -9,25 +5,38 @@
 #include "watch_utility.h"
 #include "TOTP.h"
 
-// test key: JBSWY3DPEHPK3PXP
 // Use https://cryptii.com/pipes/base32-to-hex to convert base32 to hex
 // Use https://totp.danhersam.com/ to generate test codes for verification
-static uint8_t hmacKey[] = {0x48, 0x65, 0x6c, 0x6c, 0x6f, 0x21, 0xde, 0xad, 0xbe, 0xef}; // Secret key
 
-
+static const uint8_t num_keys = 2;
-static const uint32_t TIMESTEP = 30;
+static uint8_t keys[] = {
+    0x48, 0x65, 0x6c, 0x6c, 0x6f, 0x21, 0xde, 0xad, 0xbe, 0xef, // 1 - JBSWY3DPEHPK3PXP
+    0x5c, 0x0d, 0x27, 0x6b, 0x6d, 0x9a, 0x01, 0x22, 0x20, 0x4f  // 2 - E9M348K0ADIDFBC2
+};
+static const uint8_t key_sizes[] = {
+    10,
+    10
+};
+static const uint32_t timesteps[] = {
+    30,
+    30
+};
+static const char labels[][2] = {
+    { 'a', 'b' },
+    { 'c', 'd' }
+};
 
 void totp_face_setup(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr) {
     (void) settings;
     (void) watch_face_index;
     if (*context_ptr == NULL) *context_ptr = malloc(sizeof(totp_state_t));
-    TOTP(hmacKey, sizeof(hmacKey), TIMESTEP);
 }
 
 void totp_face_activate(movement_settings_t *settings, void *context) {
     (void) settings;
     memset(context, 0, sizeof(totp_state_t));
     totp_state_t *totp_state = (totp_state_t *)context;
+    TOTP(keys, key_sizes[0], timesteps[0]);
     totp_state->timestamp = watch_utility_date_time_to_unix_time(watch_rtc_get_date_time(), movement_timezone_offsets[settings->bit.time_zone] * 60);
     totp_state->current_code = getCodeFromTimestamp(totp_state->timestamp);
 }
@@ -39,19 +48,20 @@ bool totp_face_loop(movement_event_t event, movement_settings_t *settings, void
     char buf[14];
     uint8_t valid_for;
     div_t result;
+    uint8_t index = totp_state->current_index;
 
     switch (event.event_type) {
         case EVENT_TICK:
             totp_state->timestamp++;
             // fall through
         case EVENT_ACTIVATE:
-            result = div(totp_state->timestamp, TIMESTEP);
+            result = div(totp_state->timestamp, timesteps[index]);
             if (result.quot != totp_state->steps) {
                 totp_state->current_code = getCodeFromTimestamp(totp_state->timestamp);
                 totp_state->steps = result.quot;
             }
-            valid_for = TIMESTEP - result.rem;
+            valid_for = timesteps[index] - result.rem;
-            sprintf(buf, "2f%2d%06lu", valid_for, totp_state->current_code);
+            sprintf(buf, "%c%c%2d%06lu", labels[index][0], labels[index][1], valid_for, totp_state->current_code);
 
             watch_display_string(buf, 0);
             break;
@@ -64,8 +74,18 @@ bool totp_face_loop(movement_event_t event, movement_settings_t *settings, void
         case EVENT_TIMEOUT:
             movement_move_to_face(0);
             break;
-        case EVENT_ALARM_BUTTON_DOWN:
         case EVENT_ALARM_BUTTON_UP:
+            if (index + 1 < num_keys) {
+                totp_state->current_key_offset += key_sizes[index];
+                totp_state->current_index++;
+            } else {
+                // wrap around to first key
+                totp_state->current_key_offset = 0;
+                totp_state->current_index = 0;
+            }
+            TOTP(keys + totp_state->current_key_offset, key_sizes[totp_state->current_index], timesteps[totp_state->current_index]);
+            break;
+        case EVENT_ALARM_BUTTON_DOWN:
         case EVENT_ALARM_LONG_PRESS:
         default:
             break;

movement/watch_faces/complication/totp_face.h

@@ -7,7 +7,8 @@ typedef struct {
     uint32_t timestamp;
     uint8_t steps;
     uint32_t current_code;
-
+    uint8_t current_index;
+    uint8_t current_key_offset;
 } totp_state_t;
 
 void totp_face_setup(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr);