feat: finish initial pin code implementation

src/constants.h

@@ -1,5 +1,3 @@
-// NOTE: network to sync to NTP. Uncomment it to setup the wifi connection
-
 // NOTE: used when reading data from the SD card
 #define TF_CS 5
 
@@ -32,10 +30,8 @@
 #define MQTT_WRITE_NEW_SECRET_TOPIC "esp32-totp-write-new-secret"
 
 // PIN
-#define PIN_MIN_LENGTH 10
+#define PIN_MIN_LENGTH 6
 #define PIN_MAX_LENGTH 20
-#define PIN_HASH "ccab26629773e35c4f32748e829b382e42950f04a851b72ee6aa52c0bc1141f0"
-#define PIN_SALT "=kxCImuICYdLOTPC-Xer!ksJSB5*+xIK"
 
 // UI
 #define PIN_SCREEN_NAME "pin"

src/pin.c

@@ -2,8 +2,43 @@
 #include <mbedtls/md.h>
 #include <string.h>
 #include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
 #include "constants.h"
 
+unsigned char *hex_to_bin(const char *hex_string)
+{
+	size_t len = strlen(hex_string);
+	if (len % 2 != 0)
+	{
+		return NULL; // Not a valid hexadecimal string
+	}
+
+	size_t bin_len = len / 2;
+	unsigned char *bin_data = (unsigned char *)malloc(bin_len);
+	if (bin_data == NULL)
+	{
+		return NULL; // Memory allocation failed
+	}
+
+	for (size_t i = 0; i < len; i += 2)
+	{
+		char byte[3] = {hex_string[i], hex_string[i + 1], '\0'};
+		bin_data[i / 2] = strtol(byte, NULL, 16);
+	}
+
+	return bin_data;
+}
+
+void print_hash(unsigned char *hash, size_t length)
+{
+	for (size_t i = 0; i < length; i++)
+	{
+		printf("%02x", hash[i]);
+	}
+	printf("\n");
+}
+
 bool validate_pin(const char *pin)
 {
 	if (strlen(pin) < PIN_MIN_LENGTH)
@@ -13,11 +48,12 @@ bool validate_pin(const char *pin)
 	mbedtls_md_context_t ctx;
 	mbedtls_md_init(&ctx);
 	mbedtls_md_setup(&ctx, mbedtls_md_info_from_type(MBEDTLS_MD_SHA256), 1);
-	mbedtls_md_starts(&ctx);
-	mbedtls_md_update(&ctx, (const unsigned char *)pin, strlen(pin));
-	mbedtls_md_update(&ctx, PIN_SALT, strlen((char *)PIN_SALT));
-	mbedtls_md_finish(&ctx, generated_hash);
+	mbedtls_md_hmac_starts(&ctx, PIN_KEY, strlen((char *)PIN_KEY));
+	mbedtls_md_hmac_update(&ctx, (const unsigned char *)pin, strlen(pin));
+	mbedtls_md_hmac_finish(&ctx, generated_hash);
 	mbedtls_md_free(&ctx);
 
-	return memcmp(generated_hash, PIN_HASH, sizeof(generated_hash)) == 0;
+	print_hash(generated_hash, sizeof(generated_hash) / sizeof(generated_hash[0]));
+
+	return memcmp(generated_hash, hex_to_bin(PIN_HASH), sizeof(generated_hash)) == 0;
 }

src/ui/screens/ui_pin_screen.c

@@ -29,10 +29,10 @@ void ui_pin_screen_screen_init(void)
     lv_obj_align(ui_pin_textarea, LV_ALIGN_TOP_LEFT, 0, 0);
     lv_obj_set_pos(ui_pin_textarea, 0, 0);
     lv_obj_set_width(ui_pin_textarea, LV_HOR_RES - 10);
-    lv_obj_set_height(ui_pin_textarea, 40);
+    lv_obj_set_height(ui_pin_textarea, 45);
     lv_obj_add_event_cb(ui_pin_textarea, ui_event_pin_textarea, LV_EVENT_ALL, NULL);
     lv_obj_set_style_text_font(ui_pin_textarea, &lv_font_montserrat_18, 0);
-
+    lv_obj_set_style_text_align(ui_pin_textarea, LV_TEXT_ALIGN_CENTER, 0);
 
     static const char *btnm_map[] = {
         "1", "2", "3", "4", "5", "\n",

src/ui/ui.c

@@ -6,6 +6,14 @@
 #include "ui.h"
 #include "ui_helpers.h"
 
+#ifdef PIN_HASH
+#pragma message "PIN_HASH is set to: " PIN_HASH
+#endif
+
+#ifdef PIN_KEY
+#pragma message "PIN_KEY is set to: " PIN_KEY
+#endif
+
 // CUSTOM EVENTS
 uint32_t LV_EVENT_SETUP_COMPLETE;
 
@@ -26,68 +34,85 @@ void ui_event_pin_textarea(lv_event_t *e);
 
 ///////////////////// TEST LVGL SETTINGS ////////////////////
 #if LV_COLOR_DEPTH != 16
-    #error "LV_COLOR_DEPTH should be 16bit to match SquareLine Studio's settings"
+#error "LV_COLOR_DEPTH should be 16bit to match SquareLine Studio's settings"
 #endif
 
 ///////////////////// ANIMATIONS ////////////////////
 
 ///////////////////// FUNCTIONS ////////////////////
-void ui_event_totp_component_label(lv_event_t * e) {
+void ui_event_totp_component_label(lv_event_t *e)
+{
     lv_event_code_t event_code = lv_event_get_code(e);
-    if (event_code == LV_EVENT_VALUE_CHANGED) {
+    if (event_code == LV_EVENT_VALUE_CHANGED)
+    {
         on_totp_component_label_value_changed(e);
     }
 }
 
-void ui_event_totp_component_bar(lv_event_t * e) {
+void ui_event_totp_component_bar(lv_event_t *e)
+{
     lv_event_code_t event_code = lv_event_get_code(e);
-    if (event_code == LV_EVENT_VALUE_CHANGED) {
+    if (event_code == LV_EVENT_VALUE_CHANGED)
+    {
         on_totp_component_bar_value_changed(e);
     }
 }
 
-void ui_event_keyboard_button(lv_event_t * e) {
+void ui_event_keyboard_button(lv_event_t *e)
+{
     lv_event_code_t event_code = lv_event_get_code(e);
-    if (event_code == LV_EVENT_VALUE_CHANGED) {
+    if (event_code == LV_EVENT_VALUE_CHANGED)
+    {
         on_keyboard_button_clicked(e);
     }
 }
 
-void ui_event_pin_textarea(lv_event_t * e) {
+void ui_event_pin_textarea(lv_event_t *e)
+{
     lv_event_code_t event_code = lv_event_get_code(e);
-    if (event_code == LV_EVENT_READY) {
+    if (event_code == LV_EVENT_READY)
+    {
         on_validate_pin(e);
     }
 }
 
 ///////////////////// SCREENS ////////////////////
 
-void ui_init( void ){
+void ui_init(void)
+{
     lv_disp_t *disp = lv_disp_get_default();
     lv_theme_t *theme = lv_theme_default_init(
-        disp, 
-        lv_palette_main(LV_PALETTE_BLUE), 
-        lv_palette_main(LV_PALETTE_RED), 
-        true, 
-        LV_FONT_DEFAULT
-    );
+        disp,
+        lv_palette_main(LV_PALETTE_BLUE),
+        lv_palette_main(LV_PALETTE_RED),
+        true,
+        LV_FONT_DEFAULT);
     LV_EVENT_SETUP_COMPLETE = lv_event_register_id();
     lv_disp_set_theme(disp, theme);
     ui_totp_screen_screen_init();
-    ui_pin_screen_screen_init();
     ui____initial_actions0 = lv_obj_create(NULL);
-    lv_disp_load_scr(ui_pin_screen);
-}
 
+    if (PIN_HASH && PIN_KEY)
+    {
+        ui_pin_screen_screen_init();
+        lv_disp_load_scr(ui_pin_screen);
+    }
+    else
+    {
+        lv_disp_load_scr(ui_totp_screen);
+    }
+}
 
-void refresh_totp_labels() {
+void refresh_totp_labels()
+{
     LV_LOG_INFO("refresh_totp_labels");
     lv_obj_t *container;
     lv_obj_t *label;
     int index = 0;
 
     container = lv_obj_get_child(ui_totp_screen, index);
-    while (container) {
+    while (container)
+    {
         label = lv_obj_get_child(container, 1);
         TotpValueChangeEvent event;
         event.index = index;
@@ -97,14 +122,16 @@ void refresh_totp_labels() {
     }
 }
 
-void refresh_counter_bars(){
+void refresh_counter_bars()
+{
     LV_LOG_INFO("refresh_counter_bars");
     lv_obj_t *container;
     lv_obj_t *bar;
     int index = 0;
 
     container = lv_obj_get_child(ui_totp_screen, index);
-    while (container) {
+    while (container)
+    {
         bar = lv_obj_get_child(container, 2);
         TotpValueChangeEvent event;
         event.index = index;

src/ui/ui_events.c

@@ -67,6 +67,7 @@ void on_validate_pin(lv_event_t *e){
     if(!validate_pin(pin)){
         lv_obj_t * wrongPasswordModal = lv_msgbox_create(NULL, "ERROR", "PIN isn't valid", NULL, true);
         lv_obj_center(wrongPasswordModal);
+        return;
     }
 
     lv_scr_load(ui_totp_screen);

src/ui/ui_events.h

@@ -17,6 +17,7 @@ typedef struct {
 void on_totp_component_label_value_changed(lv_event_t *e);
 void on_totp_component_bar_value_changed(lv_event_t *e);
 void on_keyboard_button_clicked(lv_event_t *e);
+void on_validate_pin(lv_event_t *e);
 
 #ifdef __cplusplus
 } /*extern "C"*/