trezor-firmware/core/src/apps/common/passphrase.py

from micropython import const

import storage.device
from trezor import wire, workflow

_MAX_PASSPHRASE_LEN = const(50)


def is_enabled() -> bool:
    return storage.device.is_passphrase_enabled()


async def get(ctx: wire.Context) -> str:
    if is_enabled():
        return await _request_from_user(ctx)
    else:
        return ""


async def _request_from_user(ctx: wire.Context) -> str:
    workflow.close_others()  # request exclusive UI access
    if storage.device.get_passphrase_always_on_device():
        from trezor.ui.layouts import request_passphrase_on_device

        passphrase = await request_passphrase_on_device(ctx, _MAX_PASSPHRASE_LEN)
    else:
        passphrase = await _request_on_host(ctx)
    if len(passphrase.encode()) > _MAX_PASSPHRASE_LEN:
        raise wire.DataError(
            f"Maximum passphrase length is {_MAX_PASSPHRASE_LEN} bytes"
        )

    return passphrase


async def _request_on_host(ctx: wire.Context) -> str:
    from trezor.messages import PassphraseAck, PassphraseRequest

    _entry_dialog()

    request = PassphraseRequest()
    ack = await ctx.call(request, PassphraseAck)
    if ack.on_device:
        from trezor.ui.layouts import request_passphrase_on_device

        if ack.passphrase is not None:
            raise wire.DataError("Passphrase provided when it should not be")
        return await request_passphrase_on_device(ctx, _MAX_PASSPHRASE_LEN)

    if ack.passphrase is None:
        raise wire.DataError(
            "Passphrase not provided and on_device is False. Use empty string to set an empty passphrase."
        )

    # non-empty passphrase
    if ack.passphrase:
        from trezor import ui
        from trezor.ui.layouts import confirm_action, confirm_blob

        await confirm_action(
            ctx,
            "passphrase_host1",
            title="Hidden wallet",
            description="Access hidden wallet?\n\nNext screen will show\nthe passphrase!",
            icon=ui.ICON_CONFIG,
        )

        await confirm_blob(
            ctx,
            "passphrase_host2",
            title="Hidden wallet",
            description="Use this passphrase?\n",
            data=ack.passphrase,
            icon=ui.ICON_CONFIG,
            icon_color=ui.ORANGE_ICON,
        )

    return ack.passphrase


def _entry_dialog() -> None:
    from trezor.ui.layouts import draw_simple_text

    draw_simple_text(
        "Passphrase entry", "Please type your\npassphrase on the\nconnected host."
    )