Add u2f(4), a HID driver for FIDO/U2F security keys

[wulf]

Summary

This driver is a stripped-down version of hidraw(4). It implements subset of commands required for FIDO/U2F keys only.

User-visible changes are:
It attaches to FIDO/U2F top level collection. So it can be automagically loaded with devd
It sets 660 root:u2f mode to device node. No need in special devd scripts
It emulates USB_GET_DEVICEINFO ioctl

[manu]

I guess this review should be splitted in multiple ones.
There is the addition of u2f(4) yes but a lot of stuff is changed in the hid code too.

[emaste]

share/man/man4/u2f.4

90

sys/amd64/conf/GENERIC

397

We need a more descriptive description -- both HIDRAW_MAKE_UHID_ALIAS and U2F_MAKE_UHID_ALIAS have the description # install /dev/uhid alias right now

[monwarez_mailoo.org]

Are there some test plan to verify that this will not break both Yubikey and Nitrokey support ?

Like for instance, upgrading the firmware on Nitrokey will require having hidraw attaching to the device.
And of course is there a test plan for firefox and chromium derivative to see if that will still work without enabling new usbhid ?

Depending on which FIDO version we are talking about, does webauth test with both enabling and disabling new usbhid ?

[wulf]

Committed as 4a04e0a6