firmware/2lib/2ui_screens.c - mirrors/cros/chromiumos/platform/vboot_reference - Git at Google

 /* Copyright 2020 The Chromium OS Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  *
  * Firmware screen definitions.
  */

 #include "2common.h"
 #include "2misc.h"
 #include "2nvstorage.h"
 #include "2ui.h"
 #include "2ui_private.h"
 #include "vboot_api.h"
 #include "vboot_kernel.h"

 #define MENU_ITEMS(a) \
 	.num_items = ARRAY_SIZE(a), \
 	.items = a

 #define ADVANCED_OPTIONS_ITEM { \
 	.text = "Advanced options", \
 	.target = VB2_SCREEN_ADVANCED_OPTIONS, \
 }

 /******************************************************************************/
 /* VB2_SCREEN_BLANK */

 static const struct vb2_screen_info blank_screen = {
 	.id = VB2_SCREEN_BLANK,
 	.name = "Blank",
 };

 /******************************************************************************/
 /* VB2_SCREEN_RECOVERY_BROKEN */

 static const struct vb2_menu_item recovery_broken_items[] = {
 	ADVANCED_OPTIONS_ITEM,
 };

 static const struct vb2_screen_info recovery_broken_screen = {
 	.id = VB2_SCREEN_RECOVERY_BROKEN,
 	.name = "Recover broken device",
 	MENU_ITEMS(recovery_broken_items),
 };

 /******************************************************************************/
 /* VB2_SCREEN_ADVANCED_OPTIONS */

 #define ADVANCED_OPTIONS_ITEM_DEVELOPER_MODE 0
 #define ADVANCED_OPTIONS_ITEM_BACK 1

 vb2_error_t advanced_options_init(struct vb2_ui_context *ui)
 {
 	if (vb2_get_sd(ui->ctx)->flags & VB2_SD_FLAG_DEV_MODE_ENABLED) {
 		ui->state.disabled_item_mask |=
 			1 << ADVANCED_OPTIONS_ITEM_DEVELOPER_MODE;
 		ui->state.selected_item = ADVANCED_OPTIONS_ITEM_BACK;
 	}

 	return VB2_REQUEST_UI_CONTINUE;
 }

 static const struct vb2_menu_item advanced_options_items[] = {
 	[ADVANCED_OPTIONS_ITEM_DEVELOPER_MODE] = {
 		.text = "Enable developer mode",
 		.target = VB2_SCREEN_RECOVERY_TO_DEV,
 	},
 	[ADVANCED_OPTIONS_ITEM_BACK] = {
 		.text = "Back",
 		.action = vb2_ui_change_root,
 	},
 };

 static const struct vb2_screen_info advanced_options_screen = {
 	.id = VB2_SCREEN_ADVANCED_OPTIONS,
 	.name = "Advanced options",
 	.init = advanced_options_init,
 	MENU_ITEMS(advanced_options_items),
 };

 /******************************************************************************/
 /* VB2_SCREEN_RECOVERY_SELECT */

 #define RECOVERY_SELECT_ITEM_PHONE 0
 #define RECOVERY_SELECT_ITEM_EXTERNAL_DISK 1

 vb2_error_t recovery_select_init(struct vb2_ui_context *ui)
 {
 	if (!vb2api_phone_recovery_enabled(ui->ctx)) {
 		VB2_DEBUG("WARNING: Phone recovery not available\n");
 		ui->state.disabled_item_mask |=
 			1 << RECOVERY_SELECT_ITEM_PHONE;
 		ui->state.selected_item = RECOVERY_SELECT_ITEM_EXTERNAL_DISK;
 	}
 	return VB2_REQUEST_UI_CONTINUE;
 }

 static const struct vb2_menu_item recovery_select_items[] = {
 	[RECOVERY_SELECT_ITEM_PHONE] = {
 		.text = "Recovery using phone",
 		.target = VB2_SCREEN_RECOVERY_PHONE_STEP1,
 	},
 	[RECOVERY_SELECT_ITEM_EXTERNAL_DISK] = {
 		.text = "Recovery using external disk",
 		.target = VB2_SCREEN_RECOVERY_DISK_STEP1,
 	},
 	ADVANCED_OPTIONS_ITEM,
 };

 static const struct vb2_screen_info recovery_select_screen = {
 	.id = VB2_SCREEN_RECOVERY_SELECT,
 	.name = "Recovery method selection",
 	.init = recovery_select_init,
 	MENU_ITEMS(recovery_select_items),
 };

 /******************************************************************************/
 /* VB2_SCREEN_RECOVERY_INVALID */

 static const struct vb2_screen_info recovery_invalid_screen = {
 	.id = VB2_SCREEN_RECOVERY_INVALID,
 	.name = "Invalid recovery inserted",
 };

 /******************************************************************************/
 /* VB2_SCREEN_RECOVERY_TO_DEV */

 #define RECOVERY_TO_DEV_ITEM_CONFIRM 0
 #define RECOVERY_TO_DEV_ITEM_CANCEL 1

 vb2_error_t recovery_to_dev_init(struct vb2_ui_context *ui)
 {
 	if (vb2_get_sd(ui->ctx)->flags & VB2_SD_FLAG_DEV_MODE_ENABLED) {
 		VB2_DEBUG("Dev mode already enabled?\n");
 		return vb2_ui_change_root(ui);
 	}

 	if (!PHYSICAL_PRESENCE_KEYBOARD && vb2ex_physical_presence_pressed()) {
 		VB2_DEBUG("Presence button stuck?\n");
 		return vb2_ui_change_root(ui);
 	}

 	/* Disable "Confirm" button for other physical presence types. */
 	if (!PHYSICAL_PRESENCE_KEYBOARD) {
 		ui->state.disabled_item_mask |=
 			1 << RECOVERY_TO_DEV_ITEM_CONFIRM;
 		ui->state.selected_item = RECOVERY_TO_DEV_ITEM_CANCEL;
 	}

 	ui->physical_presence_button_pressed = 0;

 	return VB2_REQUEST_UI_CONTINUE;
 }

 static vb2_error_t recovery_to_dev_finalize(struct vb2_ui_context *ui)
 {
 	VB2_DEBUG("Physical presence confirmed!\n");

 	/* Sanity check, should never happen. */
 	if (ui->state.screen->id != VB2_SCREEN_RECOVERY_TO_DEV ||
 	    (vb2_get_sd(ui->ctx)->flags & VB2_SD_FLAG_DEV_MODE_ENABLED) ||
 	    !vb2_allow_recovery(ui->ctx)) {
 		VB2_DEBUG("ERROR: Dev transition sanity check failed\n");
 		return VB2_REQUEST_UI_CONTINUE;
 	}

 	VB2_DEBUG("Enabling dev mode and rebooting...\n");
 	vb2_enable_developer_mode(ui->ctx);
 	return VB2_REQUEST_REBOOT_EC_TO_RO;
 }

 vb2_error_t recovery_to_dev_confirm_action(struct vb2_ui_context *ui)
 {
 	if (!ui->key_trusted) {
 		VB2_DEBUG("Reject untrusted %s confirmation\n",
 			  ui->key == VB_KEY_ENTER ? "ENTER" : "POWER");
 		return VB2_REQUEST_UI_CONTINUE;
 	}
 	return recovery_to_dev_finalize(ui);
 }

 vb2_error_t recovery_to_dev_action(struct vb2_ui_context *ui)
 {
 	int pressed;

 	if (ui->key == ' ') {
 		VB2_DEBUG("SPACE means cancel dev mode transition\n");
 		return vb2_ui_change_root(ui);
 	}

 	/* Keyboard physical presence case covered by "Confirm" action. */
 	if (PHYSICAL_PRESENCE_KEYBOARD)
 		return VB2_REQUEST_UI_CONTINUE;

 	pressed = vb2ex_physical_presence_pressed();
 	if (pressed) {
 		VB2_DEBUG("Physical presence button pressed, "
 			  "awaiting release\n");
 		ui->physical_presence_button_pressed = 1;
 		return VB2_REQUEST_UI_CONTINUE;
 	}
 	if (!ui->physical_presence_button_pressed)
 		return VB2_REQUEST_UI_CONTINUE;
 	VB2_DEBUG("Physical presence button released\n");

 	return recovery_to_dev_finalize(ui);
 }

 static const struct vb2_menu_item recovery_to_dev_items[] = {
 	[RECOVERY_TO_DEV_ITEM_CONFIRM] = {
 		.text = "Confirm",
 		.action = recovery_to_dev_confirm_action,
 	},
 	[RECOVERY_TO_DEV_ITEM_CANCEL] = {
 		.text = "Cancel",
 		.action = vb2_ui_change_root,
 	},
 };

 static const struct vb2_screen_info recovery_to_dev_screen = {
 	.id = VB2_SCREEN_RECOVERY_TO_DEV,
 	.name = "Transition to developer mode",
 	.init = recovery_to_dev_init,
 	.action = recovery_to_dev_action,
 	MENU_ITEMS(recovery_to_dev_items),
 };

 /******************************************************************************/
 /* VB2_SCREEN_RECOVERY_PHONE_STEP1 */

 static const struct vb2_screen_info recovery_phone_step1_screen = {
 	.id = VB2_SCREEN_RECOVERY_PHONE_STEP1,
 	.name = "Phone recovery step 1",
 };

 /******************************************************************************/
 /* VB2_SCREEN_RECOVERY_DISK_STEP1 */

 static const struct vb2_screen_info recovery_disk_step1_screen = {
 	.id = VB2_SCREEN_RECOVERY_DISK_STEP1,
 	.name = "Disk recovery step 1",
 };

 /******************************************************************************/
 /* VB2_SCREEN_DEVELOPER_MODE */

 #define DEVELOPER_MODE_ITEM_RETURN_TO_SECURE 0
 #define DEVELOPER_MODE_ITEM_BOOT_INTERNAL 1
 #define DEVELOPER_MODE_ITEM_BOOT_EXTERNAL 2

 vb2_error_t developer_mode_init(struct vb2_ui_context *ui)
 {
 	enum vb2_dev_default_boot default_boot =
 		vb2_get_dev_boot_target(ui->ctx);

 	/* Get me outta here! */
 	if (!vb2_dev_boot_allowed(ui->ctx))
 		vb2_ui_change_screen(ui, VB2_SCREEN_DEVELOPER_TO_NORM);

 	/* Don't show "Return to secure mode" button if GBB forces dev mode. */
 	if (vb2_get_gbb(ui->ctx)->flags & VB2_GBB_FLAG_FORCE_DEV_SWITCH_ON)
 		ui->state.disabled_item_mask |=
 			1 << DEVELOPER_MODE_ITEM_RETURN_TO_SECURE;

 	/* Don't show "Boot from external disk" button if not allowed. */
 	if (!vb2_dev_boot_usb_allowed(ui->ctx))
 		ui->state.disabled_item_mask |=
 			1 << DEVELOPER_MODE_ITEM_BOOT_EXTERNAL;

 	/* Choose the default selection. */
 	switch (default_boot) {
 	case VB2_DEV_DEFAULT_BOOT_USB:
 		ui->state.selected_item = DEVELOPER_MODE_ITEM_BOOT_EXTERNAL;
 		break;
 	default:
 		ui->state.selected_item = DEVELOPER_MODE_ITEM_BOOT_INTERNAL;
 		break;
 	}

 	ui->start_time = VbExGetTimer();

 	return VB2_REQUEST_UI_CONTINUE;
 }

 vb2_error_t vb2_ui_developer_mode_boot_internal_action(
 	struct vb2_ui_context *ui)
 {
 	if (!(ui->ctx->flags & VB2_CONTEXT_DEVELOPER_MODE) ||
 	    !vb2_dev_boot_allowed(ui->ctx)) {
 		VB2_DEBUG("ERROR: Dev mode internal boot not allowed\n");
 		return VB2_REQUEST_UI_CONTINUE;
 	}

 	if (VbTryLoadKernel(ui->ctx, VB_DISK_FLAG_FIXED)) {
 		VB2_DEBUG("ERROR: Dev mode internal boot failed\n");
 		return VB2_REQUEST_UI_CONTINUE;
 	}

 	return VB2_SUCCESS;
 }

 vb2_error_t vb2_ui_developer_mode_boot_external_action(
 	struct vb2_ui_context *ui)
 {
 	/* Sanity check, should never happen. */
 	if (!(ui->ctx->flags & VB2_CONTEXT_DEVELOPER_MODE) ||
 	    !vb2_dev_boot_allowed(ui->ctx) ||
 	    !vb2_dev_boot_usb_allowed(ui->ctx)) {
 		VB2_DEBUG("ERROR: Dev mode external boot not allowed\n");
 		return VB2_REQUEST_UI_CONTINUE;
 	}

 	if (VbTryLoadKernel(ui->ctx, VB_DISK_FLAG_REMOVABLE)) {
 		VB2_DEBUG("ERROR: Dev mode external boot failed\n");
 		return VB2_REQUEST_UI_CONTINUE;
 	}

 	return VB2_SUCCESS;
 }

 vb2_error_t developer_mode_action(struct vb2_ui_context *ui)
 {
 	struct vb2_gbb_header *gbb = vb2_get_gbb(ui->ctx);
 	const int use_short = gbb->flags & VB2_GBB_FLAG_DEV_SCREEN_SHORT_DELAY;
 	uint64_t elapsed;

 	/* Once any user interaction occurs, stop the timer. */
 	if (ui->key)
 		ui->disable_timer = 1;
 	if (ui->disable_timer)
 		return VB2_REQUEST_UI_CONTINUE;

 	elapsed = VbExGetTimer() - ui->start_time;

 	/* If we're using short delay, wait 2 seconds and don't beep. */
 	if (use_short && elapsed > 2 * VB_USEC_PER_SEC) {
 		VB2_DEBUG("Booting default target after 2s\n");
 		ui->disable_timer = 1;
 		return vb2_ui_menu_select(ui);
 	}

 	/* Otherwise, beep at 20 and 20.5 seconds. */
 	if ((ui->beep_count == 0 && elapsed > 20 * VB_USEC_PER_SEC) ||
 	    (ui->beep_count == 1 && elapsed > 20500 * VB_USEC_PER_MSEC)) {
 		VbExBeep(250, 400);
 		ui->beep_count++;
 	}

 	/* Stop after 30 seconds. */
 	if (elapsed > 30 * VB_USEC_PER_SEC) {
 		VB2_DEBUG("Booting default target after 30s\n");
 		ui->disable_timer = 1;
 		return vb2_ui_menu_select(ui);
 	}

 	return VB2_REQUEST_UI_CONTINUE;
 }

 static const struct vb2_menu_item developer_mode_items[] = {
 	[DEVELOPER_MODE_ITEM_RETURN_TO_SECURE] = {
 		.text = "Return to secure mode",
 		.target = VB2_SCREEN_DEVELOPER_TO_NORM,
 	},
 	[DEVELOPER_MODE_ITEM_BOOT_INTERNAL] = {
 		.text = "Boot from internal disk",
 		.action = vb2_ui_developer_mode_boot_internal_action,
 	},
 	[DEVELOPER_MODE_ITEM_BOOT_EXTERNAL] = {
 		.text = "Boot from external disk",
 		.action = vb2_ui_developer_mode_boot_external_action,
 	},
 	ADVANCED_OPTIONS_ITEM,
 };

 static const struct vb2_screen_info developer_mode_screen = {
 	.id = VB2_SCREEN_DEVELOPER_MODE,
 	.name = "Developer mode",
 	.init = developer_mode_init,
 	.action = developer_mode_action,
 	MENU_ITEMS(developer_mode_items),
 };

 /******************************************************************************/
 /* VB2_SCREEN_DEVELOPER_TO_NORM */

 vb2_error_t developer_to_norm_action(struct vb2_ui_context *ui)
 {
 	if (vb2_get_gbb(ui->ctx)->flags & VB2_GBB_FLAG_FORCE_DEV_SWITCH_ON) {
 		VB2_DEBUG("ERROR: dev mode forced by GBB flag\n");
 		return VB2_REQUEST_UI_CONTINUE;
 	}

 	VB2_DEBUG("Leaving dev mode\n");
 	vb2_nv_set(ui->ctx, VB2_NV_DISABLE_DEV_REQUEST, 1);
 	return VB2_REQUEST_REBOOT;
 }

 static const struct vb2_menu_item developer_to_norm_items[] = {
 	{
 		.text = "Confirm",
 		.action = developer_to_norm_action,
 	},
 	{
 		.text = "Cancel",
 		.action = vb2_ui_change_root,
 	},
 };

 static const struct vb2_screen_info developer_to_norm_screen = {
 	.id = VB2_SCREEN_DEVELOPER_TO_NORM,
 	.name = "Transition to normal mode",
 	MENU_ITEMS(developer_to_norm_items),
 };

 /******************************************************************************/
 /*
  * TODO(chromium:1035800): Refactor UI code across vboot and depthcharge.
  * Currently vboot and depthcharge maintain their own copies of menus/screens.
  * vboot detects keyboard input and controls the navigation among different menu
  * items and screens, while depthcharge performs the actual rendering of each
  * screen, based on the menu information passed from vboot.
  */
 static const struct vb2_screen_info *screens[] = {
 	&blank_screen,
 	&recovery_broken_screen,
 	&advanced_options_screen,
 	&recovery_select_screen,
 	&recovery_invalid_screen,
 	&recovery_to_dev_screen,
 	&recovery_phone_step1_screen,
 	&recovery_disk_step1_screen,
 	&developer_mode_screen,
 	&developer_to_norm_screen,
 };

 const struct vb2_screen_info *vb2_get_screen_info(enum vb2_screen id)
 {
 	int i;
 	for (i = 0; i < ARRAY_SIZE(screens); i++) {
 		if (screens[i]->id == id)
 			return screens[i];
 	}
 	return NULL;
 }
	/* Copyright 2020 The Chromium OS Authors. All rights reserved.
	* Use of this source code is governed by a BSD-style license that can be
	* found in the LICENSE file.
	*
	* Firmware screen definitions.
	*/

	#include "2common.h"
	#include "2misc.h"
	#include "2nvstorage.h"
	#include "2ui.h"
	#include "2ui_private.h"
	#include "vboot_api.h"
	#include "vboot_kernel.h"

	#define MENU_ITEMS(a) \
	.num_items = ARRAY_SIZE(a), \
	.items = a

	#define ADVANCED_OPTIONS_ITEM { \
	.text = "Advanced options", \
	.target = VB2_SCREEN_ADVANCED_OPTIONS, \
	}

	/******************************************************************************/
	/* VB2_SCREEN_BLANK */

	static const struct vb2_screen_info blank_screen = {
	.id = VB2_SCREEN_BLANK,
	.name = "Blank",
	};

	/******************************************************************************/
	/* VB2_SCREEN_RECOVERY_BROKEN */

	static const struct vb2_menu_item recovery_broken_items[] = {
	ADVANCED_OPTIONS_ITEM,
	};

	static const struct vb2_screen_info recovery_broken_screen = {
	.id = VB2_SCREEN_RECOVERY_BROKEN,
	.name = "Recover broken device",
	MENU_ITEMS(recovery_broken_items),
	};

	/******************************************************************************/
	/* VB2_SCREEN_ADVANCED_OPTIONS */

	#define ADVANCED_OPTIONS_ITEM_DEVELOPER_MODE 0
	#define ADVANCED_OPTIONS_ITEM_BACK 1

	vb2_error_t advanced_options_init(struct vb2_ui_context *ui)
	{
	if (vb2_get_sd(ui->ctx)->flags & VB2_SD_FLAG_DEV_MODE_ENABLED) {
	ui->state.disabled_item_mask \|=
	1 << ADVANCED_OPTIONS_ITEM_DEVELOPER_MODE;
	ui->state.selected_item = ADVANCED_OPTIONS_ITEM_BACK;
	}

	return VB2_REQUEST_UI_CONTINUE;
	}

	static const struct vb2_menu_item advanced_options_items[] = {
	[ADVANCED_OPTIONS_ITEM_DEVELOPER_MODE] = {
	.text = "Enable developer mode",
	.target = VB2_SCREEN_RECOVERY_TO_DEV,
	},
	[ADVANCED_OPTIONS_ITEM_BACK] = {
	.text = "Back",
	.action = vb2_ui_change_root,
	},
	};

	static const struct vb2_screen_info advanced_options_screen = {
	.id = VB2_SCREEN_ADVANCED_OPTIONS,
	.name = "Advanced options",
	.init = advanced_options_init,
	MENU_ITEMS(advanced_options_items),
	};

	/******************************************************************************/
	/* VB2_SCREEN_RECOVERY_SELECT */

	#define RECOVERY_SELECT_ITEM_PHONE 0
	#define RECOVERY_SELECT_ITEM_EXTERNAL_DISK 1

	vb2_error_t recovery_select_init(struct vb2_ui_context *ui)
	{
	if (!vb2api_phone_recovery_enabled(ui->ctx)) {
	VB2_DEBUG("WARNING: Phone recovery not available\n");
	ui->state.disabled_item_mask \|=
	1 << RECOVERY_SELECT_ITEM_PHONE;
	ui->state.selected_item = RECOVERY_SELECT_ITEM_EXTERNAL_DISK;
	}
	return VB2_REQUEST_UI_CONTINUE;
	}

	static const struct vb2_menu_item recovery_select_items[] = {
	[RECOVERY_SELECT_ITEM_PHONE] = {
	.text = "Recovery using phone",
	.target = VB2_SCREEN_RECOVERY_PHONE_STEP1,
	},
	[RECOVERY_SELECT_ITEM_EXTERNAL_DISK] = {
	.text = "Recovery using external disk",
	.target = VB2_SCREEN_RECOVERY_DISK_STEP1,
	},
	ADVANCED_OPTIONS_ITEM,
	};

	static const struct vb2_screen_info recovery_select_screen = {
	.id = VB2_SCREEN_RECOVERY_SELECT,
	.name = "Recovery method selection",
	.init = recovery_select_init,
	MENU_ITEMS(recovery_select_items),
	};

	/******************************************************************************/
	/* VB2_SCREEN_RECOVERY_INVALID */

	static const struct vb2_screen_info recovery_invalid_screen = {
	.id = VB2_SCREEN_RECOVERY_INVALID,
	.name = "Invalid recovery inserted",
	};

	/******************************************************************************/
	/* VB2_SCREEN_RECOVERY_TO_DEV */

	#define RECOVERY_TO_DEV_ITEM_CONFIRM 0
	#define RECOVERY_TO_DEV_ITEM_CANCEL 1

	vb2_error_t recovery_to_dev_init(struct vb2_ui_context *ui)
	{
	if (vb2_get_sd(ui->ctx)->flags & VB2_SD_FLAG_DEV_MODE_ENABLED) {
	VB2_DEBUG("Dev mode already enabled?\n");
	return vb2_ui_change_root(ui);
	}

	if (!PHYSICAL_PRESENCE_KEYBOARD && vb2ex_physical_presence_pressed()) {
	VB2_DEBUG("Presence button stuck?\n");
	return vb2_ui_change_root(ui);
	}

	/* Disable "Confirm" button for other physical presence types. */
	if (!PHYSICAL_PRESENCE_KEYBOARD) {
	ui->state.disabled_item_mask \|=
	1 << RECOVERY_TO_DEV_ITEM_CONFIRM;
	ui->state.selected_item = RECOVERY_TO_DEV_ITEM_CANCEL;
	}

	ui->physical_presence_button_pressed = 0;

	return VB2_REQUEST_UI_CONTINUE;
	}

	static vb2_error_t recovery_to_dev_finalize(struct vb2_ui_context *ui)
	{
	VB2_DEBUG("Physical presence confirmed!\n");

	/* Sanity check, should never happen. */
	if (ui->state.screen->id != VB2_SCREEN_RECOVERY_TO_DEV \|\|
	(vb2_get_sd(ui->ctx)->flags & VB2_SD_FLAG_DEV_MODE_ENABLED) \|\|
	!vb2_allow_recovery(ui->ctx)) {
	VB2_DEBUG("ERROR: Dev transition sanity check failed\n");
	return VB2_REQUEST_UI_CONTINUE;
	}

	VB2_DEBUG("Enabling dev mode and rebooting...\n");
	vb2_enable_developer_mode(ui->ctx);
	return VB2_REQUEST_REBOOT_EC_TO_RO;
	}

	vb2_error_t recovery_to_dev_confirm_action(struct vb2_ui_context *ui)
	{
	if (!ui->key_trusted) {
	VB2_DEBUG("Reject untrusted %s confirmation\n",
	ui->key == VB_KEY_ENTER ? "ENTER" : "POWER");
	return VB2_REQUEST_UI_CONTINUE;
	}
	return recovery_to_dev_finalize(ui);
	}

	vb2_error_t recovery_to_dev_action(struct vb2_ui_context *ui)
	{
	int pressed;

	if (ui->key == ' ') {
	VB2_DEBUG("SPACE means cancel dev mode transition\n");
	return vb2_ui_change_root(ui);
	}

	/* Keyboard physical presence case covered by "Confirm" action. */
	if (PHYSICAL_PRESENCE_KEYBOARD)
	return VB2_REQUEST_UI_CONTINUE;

	pressed = vb2ex_physical_presence_pressed();
	if (pressed) {
	VB2_DEBUG("Physical presence button pressed, "
	"awaiting release\n");
	ui->physical_presence_button_pressed = 1;
	return VB2_REQUEST_UI_CONTINUE;
	}
	if (!ui->physical_presence_button_pressed)
	return VB2_REQUEST_UI_CONTINUE;
	VB2_DEBUG("Physical presence button released\n");

	return recovery_to_dev_finalize(ui);
	}

	static const struct vb2_menu_item recovery_to_dev_items[] = {
	[RECOVERY_TO_DEV_ITEM_CONFIRM] = {
	.text = "Confirm",
	.action = recovery_to_dev_confirm_action,
	},
	[RECOVERY_TO_DEV_ITEM_CANCEL] = {
	.text = "Cancel",
	.action = vb2_ui_change_root,
	},
	};

	static const struct vb2_screen_info recovery_to_dev_screen = {
	.id = VB2_SCREEN_RECOVERY_TO_DEV,
	.name = "Transition to developer mode",
	.init = recovery_to_dev_init,
	.action = recovery_to_dev_action,
	MENU_ITEMS(recovery_to_dev_items),
	};

	/******************************************************************************/
	/* VB2_SCREEN_RECOVERY_PHONE_STEP1 */

	static const struct vb2_screen_info recovery_phone_step1_screen = {
	.id = VB2_SCREEN_RECOVERY_PHONE_STEP1,
	.name = "Phone recovery step 1",
	};

	/******************************************************************************/
	/* VB2_SCREEN_RECOVERY_DISK_STEP1 */

	static const struct vb2_screen_info recovery_disk_step1_screen = {
	.id = VB2_SCREEN_RECOVERY_DISK_STEP1,
	.name = "Disk recovery step 1",
	};

	/******************************************************************************/
	/* VB2_SCREEN_DEVELOPER_MODE */

	#define DEVELOPER_MODE_ITEM_RETURN_TO_SECURE 0
	#define DEVELOPER_MODE_ITEM_BOOT_INTERNAL 1
	#define DEVELOPER_MODE_ITEM_BOOT_EXTERNAL 2

	vb2_error_t developer_mode_init(struct vb2_ui_context *ui)
	{
	enum vb2_dev_default_boot default_boot =
	vb2_get_dev_boot_target(ui->ctx);

	/* Get me outta here! */
	if (!vb2_dev_boot_allowed(ui->ctx))
	vb2_ui_change_screen(ui, VB2_SCREEN_DEVELOPER_TO_NORM);

	/* Don't show "Return to secure mode" button if GBB forces dev mode. */
	if (vb2_get_gbb(ui->ctx)->flags & VB2_GBB_FLAG_FORCE_DEV_SWITCH_ON)
	ui->state.disabled_item_mask \|=
	1 << DEVELOPER_MODE_ITEM_RETURN_TO_SECURE;

	/* Don't show "Boot from external disk" button if not allowed. */
	if (!vb2_dev_boot_usb_allowed(ui->ctx))
	ui->state.disabled_item_mask \|=
	1 << DEVELOPER_MODE_ITEM_BOOT_EXTERNAL;

	/* Choose the default selection. */
	switch (default_boot) {
	case VB2_DEV_DEFAULT_BOOT_USB:
	ui->state.selected_item = DEVELOPER_MODE_ITEM_BOOT_EXTERNAL;
	break;
	default:
	ui->state.selected_item = DEVELOPER_MODE_ITEM_BOOT_INTERNAL;
	break;
	}

	ui->start_time = VbExGetTimer();

	return VB2_REQUEST_UI_CONTINUE;
	}

	vb2_error_t vb2_ui_developer_mode_boot_internal_action(
	struct vb2_ui_context *ui)
	{
	if (!(ui->ctx->flags & VB2_CONTEXT_DEVELOPER_MODE) \|\|
	!vb2_dev_boot_allowed(ui->ctx)) {
	VB2_DEBUG("ERROR: Dev mode internal boot not allowed\n");
	return VB2_REQUEST_UI_CONTINUE;
	}

	if (VbTryLoadKernel(ui->ctx, VB_DISK_FLAG_FIXED)) {
	VB2_DEBUG("ERROR: Dev mode internal boot failed\n");
	return VB2_REQUEST_UI_CONTINUE;
	}

	return VB2_SUCCESS;
	}

	vb2_error_t vb2_ui_developer_mode_boot_external_action(
	struct vb2_ui_context *ui)
	{
	/* Sanity check, should never happen. */
	if (!(ui->ctx->flags & VB2_CONTEXT_DEVELOPER_MODE) \|\|
	!vb2_dev_boot_allowed(ui->ctx) \|\|
	!vb2_dev_boot_usb_allowed(ui->ctx)) {
	VB2_DEBUG("ERROR: Dev mode external boot not allowed\n");
	return VB2_REQUEST_UI_CONTINUE;
	}

	if (VbTryLoadKernel(ui->ctx, VB_DISK_FLAG_REMOVABLE)) {
	VB2_DEBUG("ERROR: Dev mode external boot failed\n");
	return VB2_REQUEST_UI_CONTINUE;
	}

	return VB2_SUCCESS;
	}

	vb2_error_t developer_mode_action(struct vb2_ui_context *ui)
	{
	struct vb2_gbb_header *gbb = vb2_get_gbb(ui->ctx);
	const int use_short = gbb->flags & VB2_GBB_FLAG_DEV_SCREEN_SHORT_DELAY;
	uint64_t elapsed;

	/* Once any user interaction occurs, stop the timer. */
	if (ui->key)
	ui->disable_timer = 1;
	if (ui->disable_timer)
	return VB2_REQUEST_UI_CONTINUE;

	elapsed = VbExGetTimer() - ui->start_time;

	/* If we're using short delay, wait 2 seconds and don't beep. */
	if (use_short && elapsed > 2 * VB_USEC_PER_SEC) {
	VB2_DEBUG("Booting default target after 2s\n");
	ui->disable_timer = 1;
	return vb2_ui_menu_select(ui);
	}

	/* Otherwise, beep at 20 and 20.5 seconds. */
	if ((ui->beep_count == 0 && elapsed > 20 * VB_USEC_PER_SEC) \|\|
	(ui->beep_count == 1 && elapsed > 20500 * VB_USEC_PER_MSEC)) {
	VbExBeep(250, 400);
	ui->beep_count++;
	}

	/* Stop after 30 seconds. */
	if (elapsed > 30 * VB_USEC_PER_SEC) {
	VB2_DEBUG("Booting default target after 30s\n");
	ui->disable_timer = 1;
	return vb2_ui_menu_select(ui);
	}

	return VB2_REQUEST_UI_CONTINUE;
	}

	static const struct vb2_menu_item developer_mode_items[] = {
	[DEVELOPER_MODE_ITEM_RETURN_TO_SECURE] = {
	.text = "Return to secure mode",
	.target = VB2_SCREEN_DEVELOPER_TO_NORM,
	},
	[DEVELOPER_MODE_ITEM_BOOT_INTERNAL] = {
	.text = "Boot from internal disk",
	.action = vb2_ui_developer_mode_boot_internal_action,
	},
	[DEVELOPER_MODE_ITEM_BOOT_EXTERNAL] = {
	.text = "Boot from external disk",
	.action = vb2_ui_developer_mode_boot_external_action,
	},
	ADVANCED_OPTIONS_ITEM,
	};

	static const struct vb2_screen_info developer_mode_screen = {
	.id = VB2_SCREEN_DEVELOPER_MODE,
	.name = "Developer mode",
	.init = developer_mode_init,
	.action = developer_mode_action,
	MENU_ITEMS(developer_mode_items),
	};

	/******************************************************************************/
	/* VB2_SCREEN_DEVELOPER_TO_NORM */

	vb2_error_t developer_to_norm_action(struct vb2_ui_context *ui)
	{
	if (vb2_get_gbb(ui->ctx)->flags & VB2_GBB_FLAG_FORCE_DEV_SWITCH_ON) {
	VB2_DEBUG("ERROR: dev mode forced by GBB flag\n");
	return VB2_REQUEST_UI_CONTINUE;
	}

	VB2_DEBUG("Leaving dev mode\n");
	vb2_nv_set(ui->ctx, VB2_NV_DISABLE_DEV_REQUEST, 1);
	return VB2_REQUEST_REBOOT;
	}

	static const struct vb2_menu_item developer_to_norm_items[] = {
	{
	.text = "Confirm",
	.action = developer_to_norm_action,
	},
	{
	.text = "Cancel",
	.action = vb2_ui_change_root,
	},
	};

	static const struct vb2_screen_info developer_to_norm_screen = {
	.id = VB2_SCREEN_DEVELOPER_TO_NORM,
	.name = "Transition to normal mode",
	MENU_ITEMS(developer_to_norm_items),
	};

	/******************************************************************************/
	/*
	* TODO(chromium:1035800): Refactor UI code across vboot and depthcharge.
	* Currently vboot and depthcharge maintain their own copies of menus/screens.
	* vboot detects keyboard input and controls the navigation among different menu
	* items and screens, while depthcharge performs the actual rendering of each
	* screen, based on the menu information passed from vboot.
	*/
	static const struct vb2_screen_info *screens[] = {
	&blank_screen,
	&recovery_broken_screen,
	&advanced_options_screen,
	&recovery_select_screen,
	&recovery_invalid_screen,
	&recovery_to_dev_screen,
	&recovery_phone_step1_screen,
	&recovery_disk_step1_screen,
	&developer_mode_screen,
	&developer_to_norm_screen,
	};

	const struct vb2_screen_info *vb2_get_screen_info(enum vb2_screen id)
	{
	int i;
	for (i = 0; i < ARRAY_SIZE(screens); i++) {
	if (screens[i]->id == id)
	return screens[i];
	}
	return NULL;
	}