sendpin doesn't work on 1.2.1

[hugohn]

I am not sure if this feature has worked before, but promptpin/sendpin is not working on 1.2.1. sendpin fails to unlock the Trezor One.

You can unlock the Trezor One using the Trezor web app (trezor.js):
[trezor.js] [call] Received PinMatrixRequest {type: "PinMatrixRequestType_Current"}type: "PinMatrixRequestType_Current"
[trezor.js] [call] Sending PinMatrixAck {pin: "6666"}

But when using HWI:
./hwi --testnet -t trezor -p webusb:020:5:4:3 promptpin

Use 'sendpin' to provide the number positions for the PIN as displayed on your device's screen Use the numeric keypad to describe number positions. The layout is: 7 8 9 4 5 6 1 2 3 {"success": true}

./hwi --testnet --debug -t trezor -p webusb:020:5:4:3 sendpin 8888

DEBUG:hwilib.devices.trezorlib.transport:Enumerating WebUsbTransport: found 1 devices DEBUG:hwilib.devices.trezorlib.transport:Enumerating HidTransport: found 0 devices DEBUG:hwilib.devices.trezorlib.transport:Enumerating UdpTransport: found 0 devices DEBUG:hwilib.devices.trezorlib.transport:looking for device by full path: webusb:020:5:4:3 DEBUG:hwilib.devices.trezorlib.client:creating client instance for device: webusb:020:5:4:3 DEBUG:hwilib.devices.trezorlib.transport.protocol:sending message: GetFeatures DEBUG:hwilib.devices.trezorlib.transport.protocol:received message: Failure DEBUG:hwilib.devices.trezorlib.transport.protocol:sending message: Initialize DEBUG:hwilib.devices.trezorlib.transport.protocol:received message: Features DEBUG:hwilib.devices.trezorlib.transport.protocol:sending message: Initialize DEBUG:hwilib.devices.trezorlib.transport.protocol:received message: Features DEBUG:hwilib.devices.trezorlib.transport:Enumerating WebUsbTransport: found 1 devices DEBUG:hwilib.devices.trezorlib.transport:Enumerating HidTransport: found 0 devices DEBUG:hwilib.devices.trezorlib.transport:Enumerating UdpTransport: found 0 devices DEBUG:hwilib.devices.trezorlib.transport:looking for device by full path: webusb:020:5:4:3 DEBUG:hwilib.devices.trezorlib.client:creating client instance for device: webusb:020:5:4:3 DEBUG:hwilib.devices.trezorlib.transport.protocol:sending message: PinMatrixAck DEBUG:hwilib.devices.trezorlib.transport.protocol:received message: Failure DEBUG:hwilib.devices.trezorlib.transport.protocol:sending message: GetFeatures DEBUG:hwilib.devices.trezorlib.transport.protocol:received message: Features {"success": false}

*Note: PIN was set to 1111, "6666" and "8888" are relative positions on the blind matrix.

[hugohn]

cc @prusnak

[achow101]

Does this fail on master too?

I'm wondering if I've been experiencing this on master and just chalking it up to actually forgetting the pin I set on my test device.

[hugohn]

Yeah, I've tested 1.2.0, 1.2.1 and master. All failed to unlock.

[prusnak]

This is caused because HWI sends GetFeatures and Initialize before sendpin as can be seen from the log above:

DEBUG:hwilib.devices.trezorlib.transport.protocol:sending message: GetFeatures
DEBUG:hwilib.devices.trezorlib.transport.protocol:received message: Failure
DEBUG:hwilib.devices.trezorlib.transport.protocol:sending message: Initialize
DEBUG:hwilib.devices.trezorlib.transport.protocol:received message: Features
DEBUG:hwilib.devices.trezorlib.transport.protocol:sending message: Initialize
DEBUG:hwilib.devices.trezorlib.transport.protocol:received message: Features

This aborts the PIN workflow in the device.

Investigating further ...

[prusnak]

So it seems the following happens:

  File "/Users/stick/work/bitcoin-core/hwi/hwilib/cli.py", line 280, in main
    result = process_commands(sys.argv[1:])
  File "/Users/stick/work/bitcoin-core/hwi/hwilib/cli.py", line 257, in process_commands
    client = find_device(args.password, args.device_type, args.fingerprint, args.expert)
  File "/Users/stick/work/bitcoin-core/hwi/hwilib/commands.py", line 73, in find_device
    devices = enumerate(password)
  File "/Users/stick/work/bitcoin-core/hwi/hwilib/commands.py", line 66, in enumerate
    result.extend(imported_dev.enumerate(password))
  File "/Users/stick/work/bitcoin-core/hwi/hwilib/devices/trezor.py", line 604, in enumerate
    client.client.init_device()

HWI tries to enumerate the devices on sendpin which causes that client.client.init_device() is called on the device during enumeration - which sends GetFeatures aborting the PIN workflow.

[prusnak]

It would be ideal if there was a way how to join promptpin and sendpin into a single command called unlockpin.

Having bi-directional stdin/stdout communication interface #450 would allow us to not restart HWI all the time, just once per session leading to an easy fix of the issue.

[achow101]

Oh, I remember now. The way to use promptpin is to also specify the device path so it doesn't do the whole enumerate "guess my device" thing.

[prusnak]

Oh, I remember now. The way to use promptpin is to also specify the device path so it doesn't do the whole enumerate "guess my device" thing.

1. I think you mean sendpin not promptpin, right?
2. The original report contains both the device type and the device path for both promptpin and sendpin calls. I confirm I see the same behaviour when I try to reproduce on my machine. Providing the path does not skip the enumeration (which sends GetFeatures) to the device.

[achow101]

1. I think you mean sendpin not promptpin, right?

Oops yes.

1. The original report contains both the device type and the device path for both promptpin and sendpin calls. I confirm I see the same behaviour when I try to reproduce on my machine. Providing the path does not skip the enumeration (which sends GetFeatures) to the device.

Looking more closely, it's because the -d is the switch to use for specifying the path, not -p.

When I tested this prior to commenting, I had used the correct switch and it all worked fine. In my first comment, I was forgetting -d entirely.

[hugohn]

Looking more closely, it's because the -d is the switch to use for specifying the path, not -p.

Oh wow, confirmed that changing to -d works!!! So it was user (mine) error...

[prusnak]

Ah :-) I did the same mistake, because I copied the code from the OP.

I confirm that it works once I changed -p to -d

Closing then.