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Project description


Provides library functionality for communicating with a U2F device over USB.

Two executables are provided, u2f-enroll and u2f-sign, which support the enroll
and sign commands of U2F v0, as well as v2, as defined in the 2014-02-09
draft specification, from:

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
GNU General Public License for more details.


u2flib-host is installable by running the following command:

$ python install

Under Linux you will need to add a Udev rule to be able to access the U2F
device, or run as root. For example, the Udev rule may contain the following:

# For Udev 188 and later
# /etc/udev/rules.d/70-gnubby.rules

ACTION!="add|change", GOTO="gnubby_end"

ATTRS{idVendor}=="1050", ATTRS{idProduct}=="0211", \


# For older Udev versions
# /etc/udev/rules.d/70-gnubby.rules

ACTION=="add|change", SUBSYSTEM=="usb", \
ATTRS{idVendor}=="1050", ATTRS{idProduct}=="0211", \
TEST=="/var/run/ConsoleKit/database", \
RUN+="udev-acl --action=$env{ACTION} --device=$env{DEVNAME}"


u2flib-host requires a PyUSB compatible backend, such as libusb.

The soft U2F device implementation requires M2Crypto.


===Library use===

from u2flib_host import winusb

#Enumerate available devices
devices = winusb.list_devices()

for device in devices:
#The with block ensures that the device is opened and closed.
with device as dev:
#Send a command to the device:, data)

===Executable use===

The examples below use the soft U2F device to enroll and sign against the
u2f_server example server from the python-u2flib-server project. See that
project for more details.
The enroll step will create a new U2F key pair and store the credential in the
soft_device.json file. The sign step will use this credential to sign a
challenge given by the server.

Enroll takes a registration request as input, registering the attached device
and returns the registration response as output.

$ u2f-enroll -s soft_device.json http://localhost:8081
Enter enrollment JSON data...
{"sessionId": "", "challenge": "K0aDxsacDNqrzlaGyLZoFYbXvCJcdIhq0SSaMz-lsV4", "version": "U2F_V2", "app_id": "http://localhost:8081/app-identity"}

Touch the U2F device you wish to enroll...
[{"bd": "eyJvcmlnaW4iOiAiaHR0cDovL2xvY2FsaG9zdDo4MDgxIiwgImNoYWxsZW5nZSI6ICJLMGFEeHNhY0ROcXJ6bGFHeUxab0ZZYlh2Q0pjZElocTBTU2FNei1sc1Y0IiwgInR5cCI6ICJuYXZpZ2F0b3IuaWQuZmluaXNoRW5yb2xsbWVudCJ9", "sessionId": "", "registrationData": "BQTGnJVILHhzuTKg2XClCM5TJjF2WeK4fp9i6fj3VywzOk3d-O1sNaapAUPh-1GxoVCMY6s_jimP-nKqnZT-MGOCQIGD9Hs4qBCXMbfOPfzuB5zhFcOD95ddve67HXV8QeyPDKPZS5zDogvWyl8l4Tv2XRWGo4_6cAPPM4dPZcMreagwggGHMIIBLqADAgECAgkAmb7osQyi7BwwCQYHKoZIzj0EATAhMR8wHQYDVQQDDBZZdWJpY28gVTJGIFNvZnQgRGV2aWNlMB4XDTEzMDcxNzE0MjEwM1oXDTE2MDcxNjE0MjEwM1owITEfMB0GA1UEAwwWWXViaWNvIFUyRiBTb2Z0IERldmljZTBZMBMGByqGSM49AgEGCCqGSM49AwEHA0IABDvhl91zfpg9n7DeCedcQ8gGXUnemiXoi-JEAxz-EIhkVsMPAyzhtJZ4V3CqMZ-MOUgICt2aMxacMX9cIa8dgS2jUDBOMB0GA1UdDgQWBBQNqL-TV04iaO6mS5tjGE6ShfexnjAfBgNVHSMEGDAWgBQNqL-TV04iaO6mS5tjGE6ShfexnjAMBgNVHRMEBTADAQH_MAkGByqGSM49BAEDSAAwRQIgXJWZdbvOWdhVaG7IJtn44o21Kmi8EHsDk4cAfnZ0r38CIQD6ZPi3Pl4lXxbY7BXFyrpkiOvCpdyNdLLYbSTbvIBQOTBEAiBk3N3-gH2WPhR7EOq2-vEqrC1EZXgYs7fofhYTNk9jqwIgcAVRCeXfCLfLO7X71vKVeXaRQKCJgvmRZdB8PoPVdjw"}]

Sign takes an authentication request as input, and returns the
authentication response as output.

$ u2f-sign -s soft_device.json http://localhost:8081
Enter challenge JSON data...
{"key_handle": "gYP0ezioEJcxt849_O4HnOEVw4P3l1297rsddXxB7I8Mo9lLnMOiC9bKXyXhO_ZdFYajj_pwA88zh09lwyt5qA", "sessionId": "", "challenge": "zCfLJtWyaCk86Awi5VFtT7hhLk5yncYppYC0z2Q5xxo", "version": "U2F_V2", "app_id": "http://localhost:8081/app-identity"}

{"bd": "eyJvcmlnaW4iOiAiaHR0cDovL2xvY2FsaG9zdDo4MDgxIiwgImNoYWxsZW5nZSI6ICJ6Q2ZMSnRXeWFDazg2QXdpNVZGdFQ3aGhMazV5bmNZcHBZQzB6MlE1eHhvIiwgInR5cCI6ICJuYXZpZ2F0b3IuaWQuZ2V0QXNzZXJ0aW9uIn0", "challenge": "zCfLJtWyaCk86Awi5VFtT7hhLk5yncYppYC0z2Q5xxo", "app_id": "http://localhost:8081/app-identity", "sessionId": "", "sign": "AQAAAAEwRAIgK8HLGu8SQNPC3hI1700RsTtyXLlsn9_1sEcIcobhDi0CIFzduJ5IdGus-I-ieHTX1R-1xRCA0e29I9kChKbkkIzF"}

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