blob: 03c03d387c253b4ea5ace6d8ba20002d7953cb09 [file] [log] [blame]
trousers README
Trousers is an open-source TCG Software Stack (TSS), released under
the Common Public License. Trousers aims to be compliant with the
1.1b and 1.2 TSS specifications available from the Trusted Computing
Group website:
For information on the TrouSerS project, please send mail to the
following lists:
Use of the TSS API and TrouSerS:
Discussion of the internals of the TrouSerS implementation:
Possibly sensitive security related bugs:
Kent Yoder <>
Run-of-the-mill bug reports should use the TrouSerS bug tracker:
Packages needed to build:
automake > 1.4
autoconf > 1.4
openssl-devel >= 0.9.8
pthreads library (glibc-devel)
BUILDING the TSS 32-bit
Build and install the latest TPM device driver from either compiled in or loaded as a
module. UPDATE: This driver is now included in the vanilla 2.6.12
kernel! If you are doing this, trousers should just work after a
vanilla build. Follow the build instructions below and read
RUNNING the TSS, below.
To build trousers after you have the device driver installed:
$ sh
$ ./configure [--enable-debug] [--enable-gprof] [--enable-gcov]
$ make
# make install
Here are the default locations of files that trousers installs:
/usr/local/lib/ ->
/usr/local/lib/ ->
By default the build will place everything in /usr/local. To install
in a slightly more predictable place, use `./configure --prefix=/usr`.
'make install' will run ldconfig, but if /usr/local/lib is not in
your /etc/, this won't make a difference. You may need to
manually add it and run ldconfig as root to allow your apps to link at
run time to
BUILDING the TSS 64-bit
TrouSerS has been built and tested on ppc64 and x86_64, so please
don't hesitate to report bugs on these platforms. Building everything
64-bit will require a few more flags than are necessary for a 32-bit
platform. Here are some example instructions for ppc64:
$ sh
$ export PKG_CONFIG_PATH=/usr/lib64/pkgconfig
$ CFLAGS="-L/usr/lib64 -L/opt/gnome/lib64" LDFLAGS="-L/usr/lib64 \
-L/opt/gnome/lib64" ./configure --libdir="/usr/local/lib64"
$ make
# make install
Hopefully the above example will get you going on building in your
64-bit environment. If you need to do anything special, please send
your build steps to and I'll include it
If you've already taken ownership of your TPM using a TSS under another
operating system, there are a few issues you should be aware of.
Auth vs No-Auth SRK: In order to trick trousers into thinking it has taken
ownership of the TPM it's running on, you will need to create a persistent
storage file for trousers to use. Normally trousers would create this file
itself at the time ownership is taken. If your SRK has been given an
authorization password by the non-Linux OS, you will need to move the file
dist/ to /usr/local/var/lib/tpm/ If you've
taken ownership of your TPM without issuing a password, move
dist/ to /usr/local/var/lib/tpm/
Passwords: When entering passwords for keys you'd like to use in both
Linux and other OS's, you'll need to take note of how you entered those
passwords. The TSS spec states that when a password is entered through a
GUI popup dialog box provided by the TSS library, the password should be
converted to the UTF-16 encoding and then hashed using SHA-1, including
the UTF-16 null terminator in the hash calculation.
In order to work around this problem, specify the -u option to the
tpm-tools command line to convert the password to UTF-16 before hashing.
This, however, unfolds yet another problem...
Some TSS stacks aren't compliant with the TSS spec, in that they hash
their passwords without including the terminating null character. This
means that there are effectively two versions of any password set through
a popup dialog box. Trousers will include the terminating null character
in its hashes of UTF-16 data.
We'll do our best to track other TSS software and how it behaves. Please
see the trousers FAQ at for more information.
This TSS implementation has several components.
A) The TCS Daemon - A user space daemon that should be (according to
the TSS spec) the only portal to the TPM device driver. At boot
time, the TCS Daemon should be started, it should open the TPM
device driver and from that point on, all requests to the TPM
should go through the TSS stack. The TCSD manages TPM resources
and handles requests from TSP's both local and remote.
B) The TSP shared library - The TSP (TCG Service Provider) is a
shared library that enables applications to talk to TCSD's both
locally and remotely. The TSP also manages resources used in
commicating with the application and the TCSD and transparently
contacts the TCSD whenever necessary.
C) Persistent Storage (PS) files - TSS's have 2 different kinds of
PS for keys. PS can be thought of as a database for keys, with
each key in the database indexed by a UUID.
'User' persistent storage is maintained by the application's TSP
library. Upon writing the first key to User PS, the TSP library
creates a new file at ~/.trousers/, using the effective
user id of the process executing the call to find ~. An environment
variable, TSS_USER_PS_FILE, can also be set to point the TSP library
to a different location for the User PS. This environment variable
has the lifetime of the TSP context, so to store 2 keys in 2
different files, you will need to call Tspi_Context_Close, set the
new location, and open the context again.
'System' persistent storage is controlled by the TCS and stays
valid across all application lifetimes, TCSD restarts and system
resets. Data registered in system PS stays valid until an application
requests that it be removed. The System PS file by default is
/usr/local/var/lib/tpm/ The system PS file is initially
created when ownership of the TPM is first taken.
D) A config file. By default located in /usr/local/etc/tcsd.conf.
By default, the TCS daemon is not reachable over the internet, so if
you just plan to access it locally, running it as root with a root owned
device node is probably ok. Just make sure your device driver is loaded
and start the tcsd as root.
If you would like to run the TCS daemon as an unprivleged user,
please follow these instructions:
If you're using the device driver from a linux 2.6.12+ kernel and have
udev enabled, you need to add the following line to your
udev.permissions file (usually in /etc/udev somewhere):
and then just load the device driver with:
# modprobe tpm_atmel
# modprobe tpm_natl
start the TCS Core Services daemon, by default /usr/local/sbin/tcsd.
# startproc -u tss /usr/local/sbin/tcsd
If you've compiled trousers with './configure --enable-debug' and would like
to turn debugging output off at run-time, set the environment variable
TSS_DEBUG_OFF to any value.
# sh
# ./configure
# cd ..
# mv trousers trousers-${version}
# tar zcvf /usr/src/packages/SOURCES/trousers-${version}.tar.gz \
# rpmbuild -bb trousers-${version}/dist/trousers.spec