Commit Graph

10 Commits

Author SHA1 Message Date
James Bottomley
ecb38e2f52 tpm: split out tpm-dev.c into tpm-dev.c and tpm-common-dev.c
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 22:46:01 +03:00
Jarkko Sakkinen
745b361e98 tpm: infrastructure for TPM spaces
Added an ability to virtualize TPM commands into an isolated context
that we call a TPM space because the word context is already heavily
used in the TPM specification. Both the handle areas and bodies (where
necessary) are virtualized.

The mechanism works by adding a new parameter struct tpm_space to the
tpm_transmit() function. This new structure contains the list of virtual
handles and a buffer of page size (currently) for backing storage.

When tpm_transmit() is called with a struct tpm_space instance it will
execute the following sequence:

1. Take locks.
2. Load transient objects from the backing storage by using ContextLoad
   and map virtual handles to physical handles.
3. Perform the transaction.
4. Save transient objects to backing storage by using ContextSave and
   map resulting physical handle to virtual handle if there is such.

This commit does not implement virtualization support for hmac and
policy sessions.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Reviewed-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2017-04-03 22:46:01 +03:00
Jason Gunthorpe
fa2825da6f tpm: Begin the process to deprecate user_read_timer
For a long time the cdev read/write interface had this strange
idea that userspace had to read the result within 60 seconds otherwise
it is discarded. Perhaps this made sense under some older locking regime,
but in the modern kernel it is not required and is just dangerous.

Since something may be relying on this, double the timeout and print a
warning. We can remove the code in a few years, but this should be
enough to prevent new users.

Suggested-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2017-02-03 22:03:14 +02:00
Jarkko Sakkinen
d4816edfe7 tpm: fix a race condition in tpm2_unseal_trusted()
Unseal and load operations should be done as an atomic operation. This
commit introduces unlocked tpm_transmit() so that tpm2_unseal_trusted()
can do the locking by itself.

Fixes: 0fe5480303 ("keys, trusted: seal/unseal with TPM 2.0 chips")
Cc: stable@vger.kernel.org
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
2016-09-15 16:04:21 +03:00
Jason Gunthorpe
4e26195f24 tpm: Provide strong locking for device removal
Add a read/write semaphore around the ops function pointers so
ops can be set to null when the driver un-registers.

Previously the tpm core expected module locking to be enough to
ensure that tpm_unregister could not be called during certain times,
however that hasn't been sufficient for a long time.

Introduce a read/write semaphore around 'ops' so the core can set
it to null when unregistering. This provides a strong fence around
the driver callbacks, guaranteeing to the driver that no callbacks
are running or will run again.

For now the ops_lock is placed very high in the call stack, it could
be pushed down and made more granular in future if necessary.

Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Reviewed-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2016-06-25 17:26:35 +03:00
Jason Gunthorpe
8cfffc9d4d tpm: Get rid of chip->pdev
This is a hold over from before the struct device conversion.

- All prints should be using &chip->dev, which is the Linux
  standard. This changes prints to use tpm0 as the device name,
  not the PnP/etc ID.
- The few places involving sysfs/modules that really do need the
  parent just use chip->dev.parent instead
- We no longer need to get_device(pdev) in any places since it is no
  longer used by any of the code. The kref on the parent is held
  by the device core during device_add and dropped in device_del

Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Tested-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2016-06-25 17:26:35 +03:00
Jarkko Sakkinen
313d21eeab tpm: device class for tpm
Added own device class for TPM. Uses MISC_MAJOR:TPM_MINOR for the
first character device in order to retain backwards compatibility.
Added tpm_dev_release() back attached to the character device.

I've been running this code now for a while on my laptop (Lenovo
T430S) TrouSerS works perfectly without modifications. I don't
believe it breaks anything significantly.

The sysfs attributes that have been placed under the wrong place
and are against sysfs-rules.txt should be probably left to
stagnate under platform device directory and start defining
new sysfs attributes to the char device directory.

Guidelines for future TPM sysfs attributes should be probably
along the lines of

- Single flat set of mandatory sysfs attributes. For example,
  current PPI interface is way way too rich when you only want
  to use it to clear and activate the TPM.

- Define sysfs attribute if and only if there's no way to get
  the value from ring-3. No attributes for TPM properties. It's
  just unnecessary maintenance hurdle that we don't want.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jasob Gunthorpe <jason.gunthorpe@obsidianresearch.com>
Reviewed-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Tested-by: Scot Doyle <lkml14@scotdoyle.com>
Tested-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
2015-01-17 14:00:10 +01:00
Jarkko Sakkinen
71ed848fd7 tpm: rename chip->dev to chip->pdev
Rename chip->dev to chip->pdev to make it explicit that this not the
character device but actually represents the platform device.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jasob Gunthorpe <jason.gunthorpe@obsidianresearch.com>
Reviewed-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: Peter Huewe <peterhuewe@gmx.de>
Tested-by: Scot Doyle <lkml14@scotdoyle.com>
Tested-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
2015-01-17 14:00:09 +01:00
Jason Gunthorpe
e3302e0d6d tpm: Make tpm-dev allocate a per-file structure
This consolidates everything that is only used within tpm-dev.c
into tpm-dev.c and out of the publicly visible struct tpm_chip.

The per-file allocation lays the ground work for someday fixing the
strange forced O_EXCL behaviour of the current code.

Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Reviewed-by: Joel Schopp <jschopp@linux.vnet.ibm.com>
Reviewed-by: Ashley Lai <adlai@linux.vnet.ibm.com>
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
2014-01-06 14:37:25 +01:00
Jason Gunthorpe
afdba32e2a tpm: Pull everything related to /dev/tpmX into tpm-dev.c
CLASS-dev.c is a common idiom for Linux subsystems

This pulls all the code related to the miscdev into tpm-dev.c and makes it
static. The identical file_operation structs in the drivers are purged and the
tpm common code unconditionally creates the miscdev.

Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Reviewed-by: Joel Schopp <jschopp@linux.vnet.ibm.com>
Reviewed-by: Ashley Lai <adlai@linux.vnet.ibm.com>
[phuewe:
tpm_dev_release is now used only in this file, thus the EXPORT_SYMBOL
can be dropped and the function be marked as static.
It has no other in-kernel users]
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
2014-01-06 14:37:24 +01:00