YubiKey C Client Library (libykclient) is a C library used to validate an Yubikey OTP against Yubico’s servers. See the Yubico website for more information about Yubico and the YubiKey.
After downloading and unpacking the package tarball, you build it as follows.
./configure make check sudo make install
Warning! This is only for developers and if you don’t understand what you are doing, you should download the release files instead.
You may check out the sources using Git with the following command:
git clone https://github.com/Yubico/yubico-c-client.git
This will create a directory 'yubico-c-client'. Enter the directory:
cd yubico-c-client
Recent versions of autoconf, automake and libtool must be installed. Help2man is used to generate the manpages. Libcurl development files (headers and *.so) must also be installed.
Generate the build system using:
autoreconf --install
Then refer to the user sections above regarding building.
There is one command line tool, ykclient, to validate a particular OTP. It needs a client id, which you can generate here.
Example usage:
jas@mocca:~/src/yubico-c-client$ ./ykclient
Usage: ./ykclient <client_id> <yubikey_otp>
CLIENT_ID: your client id integer
YUBIKEY_OTP: One-time password generated by yubikey
jas@mocca:~/src/yubico-c-client$ ./ykclient --debug 16 ccccccbchvthlivuitriujjifivbvtrjkjfirllluurj
Input:
client id: 16
token: ccccccbchvthlivuitriujjifivbvtrjkjfirllluurj
Verification output (2): Yubikey OTP was replayed (REPLAYED_OTP)
jas@mocca:~/src/yubico-c-client$