Trusted Platform Module/1.2

TPM 1.2 uses the "TrouSerS" TSS (TCG software stack) by IBM, which is packaged as trousers^AUR (tcsd) and tpm-tools^AUR (userspace). All software access the TPM through the tcsd daemon.

Drivers

TPM drivers are natively supported in modern kernels, but might need to be loaded:

# modprobe tpm

Depending on your chipset, you might also need to load one of the following:

# modprobe -a tpm_{atmel,infineon,nsc,tis,crb}

Usage

TPM 1.2 is managed by tcsd, a userspace daemon that manages Trusted Computing resources and should be (according to the TSS spec) the only portal to the TPM device driver. tcsd is part of the trousers^AUR package, which was created and released by IBM, and can be configured via /etc/tcsd.conf.

To start tcsd and watch the output, run:

# tcsd -f

or simply start and enable tcsd.service.

Once tcsd is running you might also want to install tpm-tools^AUR which provides many of the command line tools for managing the TPM.

Some other tools of interest:

• tpmmanager — A Qt front-end to tpm-tools

https://github.com/Rohde-Schwarz/TPMManager || tpmmanager^AUR

• opencryptoki — A PKCS#11 implementation for Linux. It includes drivers and libraries to enable IBM cryptographic hardware as well as a software token for testing.

https://sourceforge.net/projects/opencryptoki || opencryptoki^AUR

Basics

Start off by getting basic version info:

$ tpm_version

and running a selftest:

$ tpm_selftest -l info

TPM Test Results: 00000000 ...
tpm_selftest succeeded

Securing SSH keys

There are several methods to use TPM to secure keys, but here we show a simple method based on simple-tpm-pk11-git^AUR.

First, create a new directory and generate the key:

$ mkdir ~/.simple-tpm-pk11
$ stpm-keygen -o ~/.simple-tpm-pk11/my.key

Point the configuration to the key:

~/.simple-tpm-pk11/config

key my.key

Now configure SSH to use the right PKCS11 provider:

~/.ssh/config

Host *
    PKCS11Provider /usr/lib/libsimple-tpm-pk11.so

It is now possible to generate keys with the PKCS11 provider:

$ ssh-keygen -D /usr/lib/libsimple-tpm-pk11.so

ノート: This method currently does not allow for multiple keys to be generated and used.

Troubleshooting

tcsd.service failed to start

After installing trousers^AUR, the tcsd.service service may not start correctly due to permission issues.[1] It is possible to fix this either by rebooting or by triggering the udev rule that is included in the trousers^AUR package:

# udevadm control --reload-rules
# udevadm trigger

See also

• Protecting systems with the TPM
• Embedded Security Subsystem on Thinkwiki
• TPM Fundamentals (PDF)
• Using a TPM