Commit Graph

5 Commits

Author SHA1 Message Date
Tadeusz Struk
9e1b74a63f tpm: add support for nonblocking operation
Currently the TPM driver only supports blocking calls, which doesn't allow
asynchronous IO operations to the TPM hardware.
This patch changes it and adds support for nonblocking write and a new poll
function to enable applications, which want to take advantage of this.

Tested-by: Philip Tricca <philip.b.tricca@intel.com>
Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off--by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2018-10-05 13:47:33 +03:00
Tadeusz Struk
c3d477a725 tpm: add ptr to the tpm_space struct to file_priv
Add a ptr to struct tpm_space to the file_priv and consolidate
of the write operations for the two interfaces.

Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Tested-by: Philip Tricca <philip.b.tricca@intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off--by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2018-10-05 13:47:33 +03:00
Peter Huewe
5e9fefd26b tpm, tpmrm: Mark tpmrm_write as static
sparse complains that tpmrm_write can be made static, and since it is
right we make it static.

Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2017-06-13 22:02:08 +03:00
James Bottomley
4d57856a21 tpm2: add session handle context saving and restoring to the space code
Sessions are different from transient objects in that their handles
may not be virtualized (because they're used for some hmac
calculations).  Additionally when a session is context saved, a
vestigial memory remains in the TPM and if it is also flushed, that
will be lost and the session context will refuse to load next time, so
the code is updated to flush only transient objects after a context
save.  Add a separate array (chip->session_tbl) to save and restore
sessions by handle.  Use the failure of a context save or load to
signal that the session has been flushed from the TPM and we can
remove its memory from chip->session_tbl.

Sessions are also isolated during each instance of a tpm space.  This
means that spaces shouldn't be able to see each other's sessions and
is enforced by ensuring that a space user may only refer to sessions
handles that are present in their own chip->session_tbl.  Finally when
a space is closed, all the sessions belonging to it should be flushed
so the handles may be re-used by other spaces.

Note that if we get a session save or load error, all sessions are
effectively flushed.  Even though we restore the session buffer, all
the old sessions will refuse to load after the flush and they'll be
purged from our session memory.  This means that while transient
context handling is still soft in the face of errors, session handling
is hard (any failure of the model means all sessions are lost).

Fixes-from: Colin Ian King <colin.king@canonical.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2017-04-03 22:46:02 +03:00
James Bottomley
fdc915f7f7 tpm: expose spaces via a device link /dev/tpmrm<n>
Currently the tpm spaces are not exposed to userspace.  Make this
exposure via a separate device, which can now be opened multiple times
because each read/write transaction goes separately via the space.

Concurrency is protected by the chip->tpm_mutex for each read/write
transaction separately.  The TPM is cleared of all transient objects
by the time the mutex is dropped, so there should be no interference
between the kernel and userspace.

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2017-04-03 22:46:02 +03:00