PRODUCT: Update SEED mode management

- Set SEED mode On at startup
- Add a warning if the user disables it

src/gpg_init.c

@@ -361,6 +361,8 @@ void gpg_init() {
     gpg_mse_reset();
     // pin conf
     G_gpg_vstate.pinmode = N_gpg_pstate->config_pin[0];
+    // seed conf
+    G_gpg_vstate.seed_mode = 1;
     // ux conf
     gpg_init_ux();
 }

src/gpg_ux_nanos.c

@@ -705,11 +705,52 @@ void ui_menu_seedmode_display(unsigned int value) {
     UX_MENU_DISPLAY(value, ui_menu_seedmode, ui_menu_seedmode_predisplay);
 }
 
-void ui_menu_seedmode_action(unsigned int value) {
-    G_gpg_vstate.seed_mode = value;
+static void toggle_seed(unsigned int value) {
+    if (value != 128) {
+        return;
+    }
+    if (G_gpg_vstate.seed_mode) {
+        G_gpg_vstate.seed_mode = 0;
+    } else {
+        G_gpg_vstate.seed_mode = 1;
+    }
     ui_menu_seedmode_display(0);
 }
 
+const ux_menu_entry_t ui_seed_warning[] = {
+    {NULL, NULL, -1, &C_icon_warning, "Warning", NULL, 0, 0},
+    {NULL, NULL, -1, NULL, "SEED mode", NULL, 0, 0},
+    {NULL, NULL, -1, NULL, "allows to", NULL, 0, 0},
+    {NULL, NULL, -1, NULL, "derive your", NULL, 0, 0},
+    {NULL, NULL, -1, NULL, "key from", NULL, 0, 0},
+    {NULL, NULL, -1, NULL, "Master SEED.", NULL, 0, 0},
+    {NULL, NULL, -1, NULL, "Without such", NULL, 0, 0},
+    {NULL, NULL, -1, NULL, "mode, an OS", NULL, 0, 0},
+    {NULL, NULL, -1, NULL, "or App update", NULL, 0, 0},
+    {NULL, NULL, -1, NULL, "will cause", NULL, 0, 0},
+    {NULL, NULL, -1, NULL, "your private", NULL, 0, 0},
+    {NULL, NULL, -1, NULL, "key to be", NULL, 0, 0},
+    {NULL, NULL, -1, NULL, "lost!", NULL, 0, 0},
+    {NULL, NULL, -1, NULL, "", NULL, 0, 0},
+    {NULL, NULL, -1, NULL, "Are you sure", NULL, 0, 0},
+    {NULL, NULL, -1, NULL, "you want to", NULL, 0, 0},
+    {NULL, NULL, -1, NULL, "disable", NULL, 0, 0},
+    {NULL, NULL, -1, NULL, "SEED mode?", NULL, 0, 0},
+    {NULL, ui_menu_seedmode_display, 0, &C_icon_back, "Cancel", NULL, 61, 40},
+    {NULL, toggle_seed, 128, &C_icon_validate_14, "Disable", NULL, 0, 0},
+    UX_MENU_END};
+
+void ui_menu_seedmode_action(unsigned int value) {
+    if (value == 0) {
+        // Request deactivate
+        UX_MENU_DISPLAY(0, ui_seed_warning, NULL);
+    } else {
+        // Reactivate
+        G_gpg_vstate.seed_mode = 1;
+        ui_menu_seedmode_display(0);
+    }
+}
+
 /* ------------------------------- PIN MODE UX ------------------------------ */
 
 void ui_menu_pinmode_action(unsigned int value);

src/gpg_ux_nanox.c

@@ -670,7 +670,7 @@ void ui_menu_seedmode_predisplay(void);
 UX_STEP_CB_INIT(ux_menu_seedmode_1_step,
                 bn,
                 ui_menu_seedmode_predisplay(),
-                ui_menu_seedmode_action(0),
+                ui_menu_seedmode_action(G_gpg_vstate.seed_mode),
                 {"Toggle seed mode", CUR_SEED_MODE});
 
 UX_STEP_CB(ux_menu_seedmode_2_step,
@@ -691,8 +691,7 @@ void ui_menu_seedmode_display(unsigned int value) {
     ui_flow_display(ux_flow_seedmode, value);
 }
 
-void ui_menu_seedmode_action(unsigned int value) {
-    UNUSED(value);
+static void toggle_seed() {
     if (G_gpg_vstate.seed_mode) {
         G_gpg_vstate.seed_mode = 0;
     } else {
@@ -701,6 +700,50 @@ void ui_menu_seedmode_action(unsigned int value) {
     ui_menu_seedmode_display(0);
 }
 
+UX_STEP_NOCB(ui_seed_warning_step,
+             paging,
+             {.title = "Warning",
+              .text = "SEED mode allows to derive "
+                      "your key from Master SEED.\n"
+                      "Without such mode,\n"
+                      "an OS or App update\n"
+                      "will cause your private key to be lost!\n\n"
+                      "Are you sure you want "
+                      "to disable SEED mode?"});
+
+UX_STEP_CB(ui_seed_warning_flow_cancel_step,
+           pb,
+           ui_menu_seedmode_display(0),
+           {
+               &C_icon_crossmark,
+               "Cancel",
+           });
+
+UX_STEP_CB(ui_seed_disabling_flow_confirm_step,
+           pbb,
+           toggle_seed(),
+           {
+               &C_icon_validate_14,
+               "Disable",
+               "SEED Mode",
+           });
+
+UX_FLOW(ui_seed_disabling_flow,
+        &ui_seed_warning_step,
+        &ui_seed_warning_flow_cancel_step,
+        &ui_seed_disabling_flow_confirm_step);
+
+void ui_menu_seedmode_action(unsigned int value) {
+    if (value == 1) {
+        // Current value is 'enable' -> Confirm deactivate
+        ux_flow_init(0, ui_seed_disabling_flow, NULL);
+    } else {
+        // Current value is 'disable' -> Reactivate
+        G_gpg_vstate.seed_mode = 1;
+        ui_menu_seedmode_display(0);
+    }
+}
+
 /* ------------------------------- PIN MODE UX ------------------------------ */
 
 void ui_menu_pinmode_action(unsigned int value);