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Fobnail Token provisioning

The process of Token provisioning is initialized by Platform Owner application.


Platform Owner binary expects two files: PO certificate chain cert_chain.pem and private key po_priv_key.pem, in that order. For quick start both of those files can be produced using these TL;DR instructions.

Certificate chain must begin with the root CA that was passed as FOBNAIL_PO_ROOT when Token firmware was built.

Provisioning instructions

Instructions below assume that fobnail-platform-owner was installed to a directory in $PATH variable and both required PEM files are in current directory. The process differs slightly between physical Token and emulated one, choose proper version before continuing.

  1. Plug in the Token. It will present itself as network interface, check its name in dmesg - search for lines like these one, where enp0s26u1u1 is the name of the interface:

    [54.928687] cdc_eem 1-1.1:1.0 usb0: register 'cdc_eem' at usb-0000:00:1a.0-1.1, CDC EEM Device, f6:82:61:5e:71:2a
    [55.052471] cdc_eem 1-1.1:1.0 enp0s26u1u1: renamed from usb0
    [55.153313] cdc_eem 1-1.1:1.0 enp0s26u1u1: unregister 'cdc_eem' usb-0000:00:1a.0-1.1, CDC EEM Device

    Red LED should be lit on the Token to signal that it isn't provisioned yet.

  2. Assign IP to that interface. There is no need to make it permanent, provisioning is a one-time operation. Change enp0s26u1u1 to the name of your interface:

    sudo nmcli con add save no con-name Fobnail ifname enp0s26u1u1 \
         type ethernet ip4 ipv6.method disabled
  3. Run Platform Owner application:

    fobnail-platform-owner cert_chain.pem po_priv_key.pem

    After a while, green LED will blink once to report that the Token provisioning was successful. After that Token enters idle state in which both LEDs blink shortly every 5 seconds.

  1. Network should be set up as a part of build instructions. If that isn't the case, follow instructions.

  2. Start firmware by executing the following commands (from fobnail directory). Make sure that FOBNAIL_PO_ROOT and FOBNAIL_EK_ROOT_DIR are the same as during initial build, otherwise firmware will be rebuilt. If TPM is also emulated, FOBNAIL_EXTRA_EK_ROOT in addition or instead of FOBNAIL_EK_ROOT_DIR should be provided.

    env FOBNAIL_LOG=info FOBNAIL_PO_ROOT=root_ca.crt \
        FOBNAIL_EK_ROOT_DIR=tpm_ek_roots ./ -t pc --run

    Contrary to physical Token, simulation doesn't have physical LEDs, so the state is reported in textual form:

    INFO  pal_pc::led > LED controller state: TokenNotProvisioned
  3. Run Platform Owner application:

    fobnail-platform-owner cert_chain.pem po_priv_key.pem

    This will start the provisioning, with progress and result printed in the console:

    INFO  fobnail     > new client:
    INFO  fobnail::server::token_provisioning > Commencing token provisioning
    INFO  fobnail::server::token_provisioning > Certificate chain loaded
    INFO  fobnail::server::token_provisioning > Generating new Ed25519 keypair
    INFO  fobnail::server::token_provisioning > Token provisioning complete
    INFO  pal_pc::led                         > LED controller state: TokenProvisioningComplete
    INFO  pal_pc::led                         > LED controller state: TokenWaiting
    INFO  fobnail                             > disconnect client:


In some cases (PO certificate update, change of owner or when moving from test provisioning to target one) it is necessary to perform provisioning again. To do so, previously installed by PO certificate must be removed. Instructions are different for physical and simulated Token, but in both cases all secrets protected by Token are removed for security reasons. If those are important to you, make sure you have a copy or are able to recreate them.

To unprovision physical Token you have to flash it again using these instructions. Pass new FOBNAIL_PO_ROOT if needed.

Unprovisioning in case of PC simulation is done by removing virtual flash contents by removing target/flash.bin file. After that, start the simulation as usual, flash file will be recreated with no PO certificate provisioned.

Now you can repeat provisioning instructions.

Summary and next steps

In this state Fobnail Token is provisioned and awaits platform provisioning. Further instructions can be found in example applications, like disk encryption.