Skip to content

emilcondrea/trousers

Repository files navigation

trousers README

  Trousers is an open-source TCG Software Stack (TSS), released under
the BSD License. Trousers aims to be compliant with the
1.1b and 1.2 TSS specifications available from the Trusted Computing
Group website:

http://www.trustedcomputinggroup.org


CONTACT

  For information on the TrouSerS project, please send mail to the
following lists:

Use of the TSS API and TrouSerS:
  [email protected]

Discussion of the internals of the TrouSerS implementation:
  [email protected]

Possibly sensitive security related bugs:
  Richard Maciel <[email protected]>

Run-of-the-mill bug reports should use the TrouSerS bug tracker:
  http://sourceforge.net/tracker/?group_id=126012&atid=704358


BUILD REQUIREMENTS

  Packages needed to build:

  automake > 1.4
  autoconf > 1.4
  pkgconfig
  libtool
  gtk2-devel
  openssl-devel >= 0.9.7
  pthreads library (glibc-devel)


BUILDING the TSS 32-bit

  Build and install the latest TPM device driver from
sf.net/projects/tpmdd 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 bootstrap.sh
  $ ./configure [--enable-debug] [--enable-gprof] [--enable-gcov]
  $ make
  # make install

  Here are the default locations of files that trousers installs:

  /usr/local/sbin/tcsd
  /usr/local/etc/tcsd.conf
  /usr/local/lib/libtspi.so.0.0.X
  /usr/local/lib/libtspi.so.0 -> libtspi.so.0.0.X
  /usr/local/lib/libtspi.so -> libtspi.so.0.0.X
  /usr/local/lib/libtspi.la
  /usr/local/lib/libtddl.a
  /usr/local/var/lib/tpm

  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/ld.so.conf, 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 libtspi.so.


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 bootstrap.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 [email protected] and I'll include it
here.


USING TROUSERS ON AN ALREADY OWNED TPM

  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/system.data.auth to /usr/local/var/lib/tpm/system.data.  If you've
taken ownership of your TPM without issuing a password, move
dist/system.data.noauth to /usr/local/var/lib/tpm/system.data.

  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 http://trousers.sf.net for more information.


ARCHITECTURE

  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/user.data, 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/system.data. 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.


RUNNING the TSS

  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):

  tpm[0-9]:tss:tss:0600

  and then just load the device driver with:
  # modprobe tpm_atmel
  or,
  # modprobe tpm_natl

  start the TCS Core Services daemon, by default /usr/local/sbin/tcsd.
  # /usr/local/sbin/tcsd

  If you're attempting to make the TCS Core Services daemon communicate with a
softwware TPM through TCP, you must call it using the -e option. 

  # /usr/local/sbin/tcsd -e

  The default values for hostname, port and UN socket device path are  "localhost", 
"6545" and "/var/run/tpm/tpmd_socket:0". It will search for the IN socket device,
then for an UN socket one, and then for the real TPM in this order.
The default values match with the current open source project required values, if
for instance case you need to set values of your choice, the environment variables 
for them are TCSD_TCP_DEVICE_HOSTNAME, TCSD_TCP_DEVICE_PORT if using an IN socket 
and TCSD_UN_SOCKET_DEVICE_PATH if running an UN socket.


DEBUGGING

  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.


BUILDING a TSS RPM

 # sh bootstrap.sh
 # ./configure
 # cd ..
 # mv trousers trousers-${version}
 # tar zcvf /usr/src/packages/SOURCES/trousers-${version}.tar.gz \
            trousers-${version}
 # rpmbuild -bb trousers-${version}/dist/trousers.spec

EOF