trezor-firmware/firmware/fsm_msg_common.h

/*
 * This file is part of the TREZOR project, https://trezor.io/
 *
 * Copyright (C) 2018 Pavol Rusnak <stick@satoshilabs.com>
 *
 * This library is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this library.  If not, see <http://www.gnu.org/licenses/>.
 */

void fsm_msgInitialize(const Initialize *msg)
{
	recovery_abort();
	signing_abort();
	if (msg && msg->has_state && msg->state.size == 64) {
		uint8_t i_state[64];
		if (!session_getState(msg->state.bytes, i_state, NULL)) {
			session_clear(false); // do not clear PIN
		} else {
			if (0 != memcmp(msg->state.bytes, i_state, 64)) {
				session_clear(false); // do not clear PIN
			}
		}
	} else {
		session_clear(false); // do not clear PIN
	}
	layoutHome();
	fsm_msgGetFeatures(0);
}

void fsm_msgGetFeatures(const GetFeatures *msg)
{
	(void)msg;
	RESP_INIT(Features);
	resp->has_vendor = true;         strlcpy(resp->vendor, "trezor.io", sizeof(resp->vendor));
	resp->has_major_version = true;  resp->major_version = VERSION_MAJOR;
	resp->has_minor_version = true;  resp->minor_version = VERSION_MINOR;
	resp->has_patch_version = true;  resp->patch_version = VERSION_PATCH;
	resp->has_device_id = true;      strlcpy(resp->device_id, config_uuid_str, sizeof(resp->device_id));
	resp->has_pin_protection = true; resp->pin_protection = config_hasPin();
	resp->has_passphrase_protection = true; resp->passphrase_protection = config_hasPassphraseProtection();
#ifdef SCM_REVISION
	int len = sizeof(SCM_REVISION) - 1;
	resp->has_revision = true; memcpy(resp->revision.bytes, SCM_REVISION, len); resp->revision.size = len;
#endif
	resp->has_bootloader_hash = true; resp->bootloader_hash.size = memory_bootloader_hash(resp->bootloader_hash.bytes);

    if (config_getLanguage(resp->language, sizeof(resp->language))) {
        resp->has_language = true;
    }

    if (config_getLabel(resp->label, sizeof(resp->label))) {
		resp->has_label = true;
	}

	resp->has_initialized = true; resp->initialized = config_isInitialized();
	resp->has_imported = config_hasKey(KEY_IMPORTED); resp->imported = config_isImported();
	resp->has_pin_cached = true; resp->pin_cached = session_isPinCached();
	resp->has_passphrase_cached = true; resp->passphrase_cached = session_isPassphraseCached();
	resp->has_needs_backup = true; resp->needs_backup = config_needsBackup();
	resp->has_unfinished_backup = true; resp->unfinished_backup = config_unfinishedBackup();
	resp->has_no_backup = true; resp->no_backup = config_noBackup();
	resp->has_flags = true; resp->flags = config_getFlags();
	resp->has_model = true; strlcpy(resp->model, "1", sizeof(resp->model));

	msg_write(MessageType_MessageType_Features, resp);
}

void fsm_msgPing(const Ping *msg)
{
	RESP_INIT(Success);

	if (msg->has_button_protection && msg->button_protection) {
		layoutDialogSwipe(&bmp_icon_question, _("Cancel"), _("Confirm"), NULL, _("Do you really want to"), _("answer to ping?"), NULL, NULL, NULL, NULL);
		if (!protectButton(ButtonRequestType_ButtonRequest_ProtectCall, false)) {
			fsm_sendFailure(FailureType_Failure_ActionCancelled, NULL);
			layoutHome();
			return;
		}
	}

	if (msg->has_pin_protection && msg->pin_protection) {
		CHECK_PIN
	}

	if (msg->has_passphrase_protection && msg->passphrase_protection) {
		if (!protectPassphrase()) {
			fsm_sendFailure(FailureType_Failure_ActionCancelled, NULL);
			return;
		}
	}

	if (msg->has_message) {
		resp->has_message = true;
		memcpy(&(resp->message), &(msg->message), sizeof(resp->message));
	}
	msg_write(MessageType_MessageType_Success, resp);
	layoutHome();
}

void fsm_msgChangePin(const ChangePin *msg)
{
	bool removal = msg->has_remove && msg->remove;
	if (removal) {
		if (config_hasPin()) {
			layoutDialogSwipe(&bmp_icon_question, _("Cancel"), _("Confirm"), NULL, _("Do you really want to"), _("remove current PIN?"), NULL, NULL, NULL, NULL);
		} else {
			fsm_sendSuccess(_("PIN removed"));
			return;
		}
	} else {
		if (config_hasPin()) {
			layoutDialogSwipe(&bmp_icon_question, _("Cancel"), _("Confirm"), NULL, _("Do you really want to"), _("change current PIN?"), NULL, NULL, NULL, NULL);
		} else {
			layoutDialogSwipe(&bmp_icon_question, _("Cancel"), _("Confirm"), NULL, _("Do you really want to"), _("set new PIN?"), NULL, NULL, NULL, NULL);
		}
	}
	if (!protectButton(ButtonRequestType_ButtonRequest_ProtectCall, false)) {
		fsm_sendFailure(FailureType_Failure_ActionCancelled, NULL);
		layoutHome();
		return;
	}

    if (protectChangePin(removal)) {
        if (removal) {
            fsm_sendSuccess(_("PIN removed"));
        } else {
            fsm_sendSuccess(_("PIN changed"));
        }
    }

	layoutHome();
}

void fsm_msgWipeDevice(const WipeDevice *msg)
{
	(void)msg;
	layoutDialogSwipe(&bmp_icon_question, _("Cancel"), _("Confirm"), NULL, _("Do you really want to"), _("wipe the device?"), NULL, _("All data will be lost."), NULL, NULL);
	if (!protectButton(ButtonRequestType_ButtonRequest_WipeDevice, false)) {
		fsm_sendFailure(FailureType_Failure_ActionCancelled, NULL);
		layoutHome();
		return;
	}
	config_wipe();
	// the following does not work on Mac anyway :-/ Linux/Windows are fine, so it is not needed
	// usbReconnect(); // force re-enumeration because of the serial number change
	fsm_sendSuccess(_("Device wiped"));
	layoutHome();
}

void fsm_msgGetEntropy(const GetEntropy *msg)
{
#if !DEBUG_RNG
	layoutDialogSwipe(&bmp_icon_question, _("Cancel"), _("Confirm"), NULL, _("Do you really want to"), _("send entropy?"), NULL, NULL, NULL, NULL);
	if (!protectButton(ButtonRequestType_ButtonRequest_ProtectCall, false)) {
		fsm_sendFailure(FailureType_Failure_ActionCancelled, NULL);
		layoutHome();
		return;
	}
#endif
	RESP_INIT(Entropy);
	uint32_t len = msg->size;
	if (len > 1024) {
		len = 1024;
	}
	resp->entropy.size = len;
	random_buffer(resp->entropy.bytes, len);
	msg_write(MessageType_MessageType_Entropy, resp);
	layoutHome();
}

void fsm_msgLoadDevice(const LoadDevice *msg)
{
    CHECK_PIN

	CHECK_NOT_INITIALIZED

	layoutDialogSwipe(&bmp_icon_question, _("Cancel"), _("I take the risk"), NULL, _("Loading private seed"), _("is not recommended."), _("Continue only if you"), _("know what you are"), _("doing!"), NULL);
	if (!protectButton(ButtonRequestType_ButtonRequest_ProtectCall, false)) {
		fsm_sendFailure(FailureType_Failure_ActionCancelled, NULL);
		layoutHome();
		return;
	}

	if (msg->has_mnemonic && !(msg->has_skip_checksum && msg->skip_checksum) ) {
		if (!mnemonic_check(msg->mnemonic)) {
			fsm_sendFailure(FailureType_Failure_DataError, _("Mnemonic with wrong checksum provided"));
			layoutHome();
			return;
		}
	}

	config_loadDevice(msg);
	fsm_sendSuccess(_("Device loaded"));
	layoutHome();
}

void fsm_msgResetDevice(const ResetDevice *msg)
{
    CHECK_PIN

	CHECK_NOT_INITIALIZED

	CHECK_PARAM(!msg->has_strength || msg->strength == 128 || msg->strength == 192 || msg->strength == 256, _("Invalid seed strength"));

	reset_init(
		msg->has_display_random && msg->display_random,
		msg->has_strength ? msg->strength : 128,
		msg->has_passphrase_protection && msg->passphrase_protection,
		msg->has_pin_protection && msg->pin_protection,
		msg->has_language ? msg->language : 0,
		msg->has_label ? msg->label : 0,
		msg->has_u2f_counter ? msg->u2f_counter : 0,
		msg->has_skip_backup ? msg->skip_backup : false,
		msg->has_no_backup ? msg->no_backup : false
	);
}

void fsm_msgEntropyAck(const EntropyAck *msg)
{
	if (msg->has_entropy) {
		reset_entropy(msg->entropy.bytes, msg->entropy.size);
	} else {
		reset_entropy(0, 0);
	}
}

void fsm_msgBackupDevice(const BackupDevice *msg)
{
	CHECK_INITIALIZED

	CHECK_PIN_UNCACHED

	(void)msg;
    char mnemonic[MAX_MNEMONIC_LEN + 1];
    if (config_getMnemonic(mnemonic, sizeof(mnemonic))) {
        reset_backup(true, mnemonic);
    }
    memzero(mnemonic, sizeof(mnemonic));
}

void fsm_msgCancel(const Cancel *msg)
{
	(void)msg;
	recovery_abort();
	signing_abort();
	ethereum_signing_abort();
	fsm_sendFailure(FailureType_Failure_ActionCancelled, NULL);
}

void fsm_msgClearSession(const ClearSession *msg)
{
	(void)msg;
	session_clear(true); // clear PIN as well
	layoutScreensaver();
	fsm_sendSuccess(_("Session cleared"));
}

void fsm_msgApplySettings(const ApplySettings *msg)
{
	CHECK_PARAM(msg->has_label || msg->has_language || msg->has_use_passphrase || msg->has_homescreen || msg->has_auto_lock_delay_ms,
				_("No setting provided"));

	CHECK_PIN

	if (msg->has_label) {
		layoutDialogSwipe(&bmp_icon_question, _("Cancel"), _("Confirm"), NULL, _("Do you really want to"), _("change name to"), msg->label, "?", NULL, NULL);
		if (!protectButton(ButtonRequestType_ButtonRequest_ProtectCall, false)) {
			fsm_sendFailure(FailureType_Failure_ActionCancelled, NULL);
			layoutHome();
			return;
		}
	}
	if (msg->has_language) {
		layoutDialogSwipe(&bmp_icon_question, _("Cancel"), _("Confirm"), NULL, _("Do you really want to"), _("change language to"), msg->language, "?", NULL, NULL);
		if (!protectButton(ButtonRequestType_ButtonRequest_ProtectCall, false)) {
			fsm_sendFailure(FailureType_Failure_ActionCancelled, NULL);
			layoutHome();
			return;
		}
	}
	if (msg->has_use_passphrase) {
		layoutDialogSwipe(&bmp_icon_question, _("Cancel"), _("Confirm"), NULL, _("Do you really want to"), msg->use_passphrase ? _("enable passphrase") : _("disable passphrase"), _("protection?"), NULL, NULL, NULL);
		if (!protectButton(ButtonRequestType_ButtonRequest_ProtectCall, false)) {
			fsm_sendFailure(FailureType_Failure_ActionCancelled, NULL);
			layoutHome();
			return;
		}
	}
	if (msg->has_homescreen) {
		layoutDialogSwipe(&bmp_icon_question, _("Cancel"), _("Confirm"), NULL, _("Do you really want to"), _("change the home"), _("screen?"), NULL, NULL, NULL);
		if (!protectButton(ButtonRequestType_ButtonRequest_ProtectCall, false)) {
			fsm_sendFailure(FailureType_Failure_ActionCancelled, NULL);
			layoutHome();
			return;
		}
	}

	if (msg->has_auto_lock_delay_ms) {
		layoutDialogSwipe(&bmp_icon_question, _("Cancel"), _("Confirm"), NULL, _("Do you really want to"), _("change auto-lock"), _("delay?"), NULL, NULL, NULL);
		if (!protectButton(ButtonRequestType_ButtonRequest_ProtectCall, false)) {
			fsm_sendFailure(FailureType_Failure_ActionCancelled, NULL);
			layoutHome();
			return;
		}
	}

	if (msg->has_label) {
		config_setLabel(msg->label);
	}
	if (msg->has_language) {
		config_setLanguage(msg->language);
	}
	if (msg->has_use_passphrase) {
		config_setPassphraseProtection(msg->use_passphrase);
	}
	if (msg->has_homescreen) {
		config_setHomescreen(msg->homescreen.bytes, msg->homescreen.size);
	}
	if (msg->has_auto_lock_delay_ms) {
		config_setAutoLockDelayMs(msg->auto_lock_delay_ms);
	}
	fsm_sendSuccess(_("Settings applied"));
	layoutHome();
}

void fsm_msgApplyFlags(const ApplyFlags *msg)
{
    CHECK_PIN

	if (msg->has_flags) {
		config_applyFlags(msg->flags);
	}
	fsm_sendSuccess(_("Flags applied"));
}

void fsm_msgRecoveryDevice(const RecoveryDevice *msg)
{
    CHECK_PIN

	const bool dry_run = msg->has_dry_run ? msg->dry_run : false;
	if (!dry_run) {
		CHECK_NOT_INITIALIZED
	}

	CHECK_PARAM(!msg->has_word_count || msg->word_count == 12 || msg->word_count == 18 || msg->word_count == 24, _("Invalid word count"));

	recovery_init(
		msg->has_word_count ? msg->word_count : 12,
		msg->has_passphrase_protection && msg->passphrase_protection,
		msg->has_pin_protection && msg->pin_protection,
		msg->has_language ? msg->language : 0,
		msg->has_label ? msg->label : 0,
		msg->has_enforce_wordlist && msg->enforce_wordlist,
		msg->has_type ? msg->type : 0,
		msg->has_u2f_counter ? msg->u2f_counter : 0,
		dry_run
	);
}

void fsm_msgWordAck(const WordAck *msg)
{
	recovery_word(msg->word);
}

void fsm_msgSetU2FCounter(const SetU2FCounter *msg)
{
	layoutDialogSwipe(&bmp_icon_question, _("Cancel"), _("Confirm"), NULL, _("Do you want to set"), _("the U2F counter?"), NULL, NULL, NULL, NULL);
	if (!protectButton(ButtonRequestType_ButtonRequest_ProtectCall, false)) {
		fsm_sendFailure(FailureType_Failure_ActionCancelled, NULL);
		layoutHome();
		return;
	}
	config_setU2FCounter(msg->u2f_counter);
	fsm_sendSuccess(_("U2F counter set"));
	layoutHome();
}