Asymmetric keys were introduced in linux-3.7 to verify the signature on
signed kernel modules. The asymmetric keys infrastructure abstracts the
signature verification from the crypto details. This patch adds IMA/EVM
signature verification using asymmetric keys. Support for additional
signature verification methods can now be delegated to the asymmetric
key infrastructure.

Although the module signature header and the IMA/EVM signature header
could use the same format, to minimize the signature length and save
space in the extended attribute, this patch defines a new IMA/EVM
header format.  The main difference is that the key identifier is a
sha1[12 - 19] hash of the key modulus and exponent, similar to the
current implementation.  The only purpose of the key identifier is to
identify the corresponding key in the kernel keyring.  ima-evm-utils
was updated to support the new signature format.

While asymmetric signature verification functionality supports many
different hash algorithms, the hash used in this patch is calculated
during the IMA collection phase, based on the configured algorithm.
The default algorithm is sha1, but for backwards compatibility md5
is supported.  Due to this current limitation, signatures should be
generated using a sha1 hash algorithm.

Changes in this patch:
- Functionality has been moved to separate source file in order to get rid of
  in source #ifdefs.
- keyid is derived according to the RFC 3280. It does not require to assign
  IMA/EVM specific "description" when loading X509 certificate. Kernel
  asymmetric key subsystem automatically generate the description. Also
  loading a certificate does not require using of ima-evm-utils and can be
  done using keyctl only.
- keyid size is reduced to 32 bits to save xattr space.  Key search is done
  using partial match functionality of asymmetric_key_match().
- Kconfig option title was changed
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

Rename hash calculation functions to reflect meaning
and change argument order in conventional way.
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

Old crypto hash API internally uses shash API.
Using shash API directly is more efficient.
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

The IMA policy permits specifying rules to enable or disable
measurement/appraisal/audit based on the file system magic number.
If, for example, the policy contains an ext4 measurement rule,
the rule is enabled for all ext4 partitions.

Sometimes it might be necessary to enable measurement/appraisal/audit
only for one partition and disable it for another partition of the
same type.  With the existing IMA policy syntax, this can not be done.

This patch provides support for IMA policy rules to specify the file
system by its UUID (eg. fsuuid=397449cd-687d-4145-8698-7fed4a3e0363).

For partitions not being appraised, it might be a good idea to mount
file systems with the 'noexec' option to prevent executing non-verified
binaries.
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

EVM uses the same key for all file systems to calculate the HMAC,
making it possible to paste inodes from one file system on to another
one, without EVM being able to detect it.  To prevent such an attack,
it is necessary to make the EVM HMAC file system specific.

This patch uses the file system UUID, a file system unique identifier,
to bind the EVM HMAC to the file system. The value inode->i_sb->s_uuid
is used for the HMAC hash calculation, instead of using it for deriving
the file system specific key.  Initializing the key for every inode HMAC
calculation is a bit more expensive operation than adding the uuid to
the HMAC hash.

Changing the HMAC calculation method or adding additional info to the
calculation, requires existing EVM labeled file systems to be relabeled.
This patch adds a Kconfig HMAC version option for backwards compatability.

Changelog v1:
- squash "hmac version setting"
Changelog v0:
- add missing Kconfig depends (Mimi)
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

Reported-by: Peter Hüwe <peterhuewe@gmx.de>
Reviewed-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>

We don't need a temporary variable just to store the return value which
gets return in the next statement.
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>

Err is never read before it is assigned again -> remove the dead
assigment.
Found with clang static analyzer
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>

With the HOTPLUG changes 3.8 this attribute is going away.
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>

We don't need to call memcpy for one byte, but assign it directly.
And to make the offset clearer we use the array syntax on the subsequent
call to memset to make the relationship clearer.
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>

Reported-by: Peter Hüwe <PeterHuewe@gmx.de>
Signed-off-by: Peter Hüwe <PeterHuewe@gmx.de>
Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>

The TIS specification (pg 47) says the valid bit must be set, but
the TPM will not set it until it has completed its internal startup.

The driver checks that the valid bit is set during request_locality,
but it issues a TPM_ACCESS_REQUEST_USE without validating the
valid bit is set.

Some TPMs will ignore the TPM_ACCESS_REQUEST_USE, until valid is
set which causes the request_locality to timeout, which breaks the
driver attach.

Wait one timeout unit for valid to assert. If valid does not assert
then assume -ENODEV.

Seen on embedded with a:
1.2 TPM (device-id 0x3204, rev-id 64)
Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>

Support cancellation of TPM commands when driver is used in interrupt
mode.
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>

On one of my machines the cancellation of TPM commands does not work.
The reason is that by writing into sysfs 'cancel' the tpm_tis_ready
call causes the status flag TPM_STS_VALID to be set in the statusregister.
However, the TIS driver seems to wait for TPM_STS_COMMAND_READY.
Once a 2nd time sysfs 'cancel' is written to, the TPM_STS_COMMAND_READY flag
also gets set, resulting in TPM_STS_VALID|TPM_STS_COMMAND_READY to be
read from the status register.

This patch now converts req_canceled into a function to enable more complex
comparisons against possible cancellation status codes.
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>

Store the TPM vendor ID for later use.
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>

We've been testing an alternative TPM for our embedded products and
found random kernel boot failures due to time outs after the continue
self test command.

This was happening randomly, and has been *very* hard to track down, but
it
looks like with this chip there is some kind of race with the
tpm_tis_status()
check of TPM_STS_COMMAND_READY. If things get there 'too fast' then
it sees the chip is ready, or tpm_tis_ready() works. Otherwise it takes
somewhere over 400ms before the chip will return TPM_STS_COMMAND_READY.

Adding some delay after tpm_continue_selftest() makes things reliably
hit the failure path, otherwise it is a crapshot.

The spec says it should be returning TPM_WARN_DOING_SELFTEST, not
holding
off on ready..

Boot log during this event looks like this:

tpm_tis 70030000.tpm_tis: 1.2 TPM (device-id 0x3204, rev-id 64)
tpm_tis 70030000.tpm_tis: Issuing TPM_STARTUP
tpm_tis 70030000.tpm_tis: tpm_transmit: tpm_send: error -62
tpm_tis 70030000.tpm_tis: [Hardware Error]: TPM command timed out during
continue self test
tpm_tis 70030000.tpm_tis: tpm_transmit: tpm_send: error -62
tpm_tis 70030000.tpm_tis: [Hardware Error]: TPM command timed out during
continue self test
tpm_tis 70030000.tpm_tis: tpm_transmit: tpm_send: error -62
tpm_tis 70030000.tpm_tis: [Hardware Error]: TPM command timed out during
continue self test
tpm_tis 70030000.tpm_tis: tpm_transmit: tpm_send: error -62
tpm_tis 70030000.tpm_tis: [Hardware Error]: TPM command timed out during
continue self test

The other TPM vendor we use doesn't show this wonky behaviour:
tpm_tis 70030000.tpm_tis: 1.2 TPM (device-id 0xFE, rev-id 70)
Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>

When no i2c bus exists, user-space can cause an oops by triggering a
device probe through a message sent to an i2c "new_device" sysfs entry.
Adding a check for a NULL i2c client structure in the probe function
closes the hole.

This patch also fixes accessing the NULL client struct in the print
function call reporting the error.
Reported-by: Peter Hüwe <PeterHuewe@gmx.de>
Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>

This patch converts the suspend and resume functions for
tpm_i2c_stm_st33 to the new dev_pm_ops.
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>

 * STMicroelectronics version 1.2.0, Copyright (C) 2010
 * STMicroelectronics comes with ABSOLUTELY NO WARRANTY.
 * This is free software, and you are welcome to redistribute it
 * under certain conditions.

This is the driver for TPM chip from ST Microelectronics.

If you have a TPM security chip from STMicroelectronics working with
an I2C, in menuconfig or .config choose the tpm driver on
device --> tpm and activate the protocol of your choice before compiling
the kernel.
The driver will be accessible from within Linux.

Tested on linux x86/x64, beagleboard REV B & XM REV C and CHROMIUM OS
Signed-off-by: Mathias Leblanc <mathias.leblanc@st.com>
Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>

Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>

 Store the i2c_client struct in the vendor private pointer. Get rid of
the unnecessary include/linux/i2c/ header. Moved include files into the
driver c file. Fix smatch warnings. Make use of module_i2c_driver().
Removed unused code from the tpm_stm_st33_i2c.h file. Fix return
variable signedness in tpm_stm_i2c_send() and tpm_st33_i2c_probe().
Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>

  "data" was too generic a name for what's being used as a generic
private pointer by vendor-specific code. Rename it to "priv" and provide
a #define for users.
Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>

 * STMicroelectronics version 1.2.0, Copyright (C) 2010
 * STMicroelectronics comes with ABSOLUTELY NO WARRANTY.
 * This is free software, and you are welcome to redistribute it
 * under certain conditions.

This is the driver for TPM chip from ST Microelectronics.

If you have a TPM security chip from STMicroelectronics working with
an I2C, in menuconfig or .config choose the tpm driver on
device --> tpm and activate the protocol of your choice before compiling
the kernel.
The driver will be accessible from within Linux.

Tested on linux x86/x64 on kernel 3.x
Signed-off-by: Mathias Leblanc <mathias.leblanc@st.com>
Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>

Bool initializations should use true and false.  Bool tests don't need
comparisons.  Based on contributions from Joe Perches, Rusty Russell
and Bruce W Allan.

The semantic patch that makes this output is available
in scripts/coccinelle/misc/boolinit.cocci.

More information about semantic patching is available at
http://coccinelle.lip6.fr/Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>

This seems to be preferred these days.
Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Reviewed-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>

The TPM will respond to TPM_GET_CAP with TPM_ERR_INVALID_POSTINIT if
TPM_STARTUP has not been issued. Detect this and automatically
issue TPM_STARTUP.

This is for embedded applications where the kernel is the first thing
to touch the TPM.
Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Tested-by: Peter Huewe <peter.huewe@infineon.com>
Reviewed-by: Peter Huewe <peter.huewe@infineon.com>
Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>

This patch changes the semantics of the duration calculation for an
ordinal, by masking out the higher bits of a tpm command, which specify
whether it's an TPM_PROTECTED_COMMAND, TPM_UNPROTECTED_COMMAND,
TPM_CONNECTION_COMMAND, TPM_CONNECTION_COMMAND, TPM_VENDOR_COMMAND.
(See TPM Main Spec Part 2 Section 17 for details).

For all TPM_PROTECTED and TPM_CONNECTION commands the results are
unchanged.
The TPM_UNPROTECTED commands are TSS commands and thus irrelevant as
they are not sent to the tpm.
For vendor commands the semantics change for ordinals 10 and 11 but
they were probably wrong anyway.

For everything else which has the ordinal set to 10 or 11 the semantics
change as it now uses TPM_UNDEFINED instead of TPM_SHORT which was
probably wrong anyway (but irrelevant as not defined by the standard).

This patch also gets rid of the (false positive) smatch warning:
 drivers/char/tpm/tpm.c:360 tpm_calc_ordinal_duration() error: buffer
 overflow 'tpm_protected_ordinal_duration' 12 <= 243
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>

The entries in tpm_protected_ordinal_duration are exactly the same as
the first 12 in tpm_ordinal_duration, so we can simply remove this one,
and save some bytes.

This does not change the behavior of the driver.
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>

Reviewed-by: Peter Huewe <peter.huewe@infineon.com>
Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>

Remove MIN, MAX and ABS macros that are duplicates kernel's native
implementation.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>

In existing use case, copying of the decoded data is unnecessary in
pkcs_1_v1_5_decode_emsa. It is just enough to get pointer to the message.
Removing copying and extra buffer allocation.
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>

Different hooks can require different methods for appraising a
file's integrity.  As a result, an integrity appraisal status is
cached on a per hook basis.

Only a hook specific rule, requires the inode to be re-appraised.
This patch eliminates unnecessary appraisals.
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>

With the new IMA policy 'appraise_type=' option, different hooks
can require different methods for appraising a file's integrity.

For example, the existing 'ima_appraise_tcb' policy defines a
generic rule, requiring all root files to be appraised, without
specfying the appraisal method.  A more specific rule could require
all kernel modules, for example, to be signed.

appraise fowner=0 func=MODULE_CHECK appraise_type=imasig
appraise fowner=0

As a result, the integrity appraisal results for the same inode, but
for different hooks, could differ.  This patch caches the integrity
appraisal results on a per hook basis.

Changelog v2:
- Rename ima_cache_status() to ima_set_cache_status()
- Rename and move get_appraise_status() to ima_get_cache_status()
Changelog v0:
- include IMA_APPRAISE/APPRAISED_SUBMASK in IMA_DO/DONE_MASK (Dmitry)
- Support independent MODULE_CHECK appraise status.
- fixed IMA_XXXX_APPRAISE/APPRAISED flags
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>

In preparation for hook specific appraise status results, increase
the iint flags size.
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>

The 'security.ima' extended attribute may contain either the file data's
hash or a digital signature.  This patch adds support for requiring a
specific extended attribute type.  It extends the IMA policy with a new
keyword 'appraise_type=imasig'.  (Default is hash.)

Changelog v2:
- Fixed Documentation/ABI/testing/ima_policy option syntax
Changelog v1:
- Differentiate between 'required' vs. 'actual' extended attribute
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

This patch forbids write access to files with digital signatures, as they
are considered immutable.
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

Define a new function ima_d_path(), which returns the full pathname.
This function will be used further, for example, by the directory
verification code.
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

This patch reduces size of the iint structure by 8 bytes.
It saves about 15% of iint cache memory.
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

Rename FILE_MMAP hook to MMAP_CHECK to be consistent with the other
hook names.
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>

Hexdump is not really helping. Audit messages prints error messages.
Remove it.
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>