Commit Graph

23 Commits

Author SHA1 Message Date
Kees Cook 782779b60f tpm: Actually fail on TPM errors during "get random"
A "get random" may fail with a TPM error, but those codes were returned
as-is to the caller, which assumed the result was the number of bytes
that had been written to the target buffer, which could lead to a kernel
heap memory exposure and over-read.

This fixes tpm1_get_random() to mask positive TPM errors into -EIO, as
before.

[   18.092103] tpm tpm0: A TPM error (379) occurred attempting get random
[   18.092106] usercopy: Kernel memory exposure attempt detected from SLUB object 'kmalloc-64' (offset 0, size 379)!

Link: https://bugzilla.redhat.com/show_bug.cgi?id=1650989
Reported-by: Phil Baker <baker1tex@gmail.com>
Reported-by: Craig Robson <craig@zhatt.com>
Fixes: 7aee9c52d7 ("tpm: tpm1: rewrite tpm1_get_random() using tpm_buf structure")
Cc: Laura Abbott <labbott@redhat.com>
Cc: Tomas Winkler <tomas.winkler@intel.com>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Tomas Winkler <tomas.winkler@intel.com>
Tested-by: Bartosz Szczepanek <bsz@semihalf.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2019-06-24 23:57:49 +03:00
Roberto Sassu 879b589210 tpm: retrieve digest size of unknown algorithms with PCR read
Currently, the TPM driver retrieves the digest size from a table mapping
TPM algorithms identifiers to identifiers defined by the crypto subsystem.
If the algorithm is not defined by the latter, the digest size can be
retrieved from the output of the PCR read command.

The patch modifies the definition of tpm_pcr_read() and tpm2_pcr_read() to
pass the desired hash algorithm and obtain the digest size at TPM startup.
Algorithms and corresponding digest sizes are stored in the new structure
tpm_bank_info, member of tpm_chip, so that the information can be used by
other kernel subsystems.

tpm_bank_info contains: the TPM algorithm identifier, necessary to generate
the event log as defined by Trusted Computing Group (TCG); the digest size,
to pad/truncate a digest calculated with a different algorithm; the crypto
subsystem identifier, to calculate the digest of event data.

This patch also protects against data corruption that could happen in the
bus, by checking that the digest size returned by the TPM during a PCR read
matches the size of the algorithm passed to tpm2_pcr_read().

For the initial PCR read, when digest sizes are not yet available, this
patch ensures that the amount of data copied from the output returned by
the TPM does not exceed the size of the array data are copied to.

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Acked-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2019-02-13 09:48:51 +02:00
Roberto Sassu aa04247593 tpm: rename and export tpm2_digest and tpm2_algorithms
Rename tpm2_* to tpm_* and move the definitions to include/linux/tpm.h so
that these can be used by other kernel subsystems (e.g. IMA).

Also, set the length of the digest array in tpm_digest to a new constant
named TPM_MAX_DIGEST_SIZE, equal to SHA512_DIGEST_SIZE.

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Acked-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2019-02-13 09:48:51 +02:00
Roberto Sassu bcfff8384f tpm: dynamically allocate the allocated_banks array
This patch renames active_banks (member of tpm_chip) to allocated_banks,
stores the number of allocated PCR banks in nr_allocated_banks (new member
of tpm_chip), and replaces the static array with a pointer to a dynamically
allocated array.

tpm2_get_pcr_allocation() determines if a PCR bank is allocated by checking
the mask in the TPML_PCR_SELECTION structure returned by the TPM for
TPM2_Get_Capability(). If a bank is not allocated, the TPM returns that
bank in TPML_PCR_SELECTION, with all bits in the mask set to zero. In this
case, the bank is not included in chip->allocated_banks, to avoid that TPM
driver users unnecessarily calculate a digest for that bank.

One PCR bank with algorithm set to SHA1 is always allocated for TPM 1.x.

As a consequence of the introduction of nr_allocated_banks,
tpm_pcr_extend() does not check anymore if the algorithm stored in tpm_chip
is equal to zero.

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.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>
2019-02-13 09:48:50 +02:00
Jarkko Sakkinen 47a6c28b68 tpm: remove @flags from tpm_transmit()
Remove @flags from tpm_transmit() API. It is no longer used for
anything.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Tested-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Reviewed-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Tested-by: Alexander Steffen <Alexander.Steffen@infineon.com>
2019-02-13 09:48:46 +02:00
Jarkko Sakkinen 5faafbab77 tpm: remove @space from tpm_transmit()
Remove @space from tpm_transmit() API` in order to completely remove the
bound between low-level transmission functionality and TPM spaces. The
only real dependency existing is the amount of data saved before trying
to send a command to the TPM.

It doesn't really matter if we save always a bit more than needed so
this commit changes the amount saved always to be the size of the TPM
header and three handles.

Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Tested-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Reviewed-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Tested-by: Alexander Steffen <Alexander.Steffen@infineon.com>
2019-02-13 09:48:12 +02:00
Jarkko Sakkinen 412eb58558 tpm: use tpm_buf in tpm_transmit_cmd() as the IO parameter
Since we pass an initialized struct tpm_buf instance in every call site
now, it is cleaner to pass that directly to the tpm_transmit_cmd() as
the TPM command/response buffer.

Fine-tune a little bit tpm_transmit() and tpm_transmit_cmd() comments
while doing this.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Tested-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Reviewed-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Tested-by: Alexander Steffen <Alexander.Steffen@infineon.com>
2019-02-13 09:47:01 +02:00
Jerry Snitselaar 36ce089758 tpm: don't return bool from update_timeouts
Set tpm_chip->timeouts_adjusted directly in the update_timeouts
code instead of returning bool. In case of tpm read failing
print warning that the read failed and continue on.

Signed-off-by: Jerry Snitselaar <jsnitsel@redhat.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2019-02-13 09:47:01 +02:00
Tomas Winkler 95adc6b410 tpm: use u32 instead of int for PCR index
The TPM specs defines PCR index as a positive number, and there is
no reason to use a signed number. It is also a possible security
issue as currently no functions check for a negative index,
which may become a large number when converted to u32.

Adjust the API to use u32 instead of int in all PCR related
functions.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.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>
2018-11-13 13:46:31 +02:00
Tomas Winkler c82e59541a tpm1: reimplement tpm1_continue_selftest() using tpm_buf
Reimplement tpm1_continue_selftest() using tpm_buf structure.
This is the last command using the old tpm_cmd_t structure
and now the structure can be removed.

Cc: Nayna Jain <nayna@linux.vnet.ibm.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.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>
2018-11-13 13:46:31 +02:00
Tomas Winkler 9315e73ac8 tpm1: reimplement SAVESTATE using tpm_buf
In tpm1_pm_suspend() function reimplement,
TPM_ORD_SAVESTATE comamnd using tpm_buf.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.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>
2018-11-13 13:46:31 +02:00
Tomas Winkler cfddcb05e1 tpm1: rename tpm1_pcr_read_dev to tpm1_pcr_read()
Rename tpm1_pcr_read_dev to tpm1_pcr_read() to match
the counterpart tpm2_pcr_read().

Signed-off-by: Tomas Winkler <tomas.winkler@intel.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>
2018-11-13 13:46:31 +02:00
Tomas Winkler 5e335b5ecf tpm1: implement tpm1_pcr_read_dev() using tpm_buf structure
Implement tpm1_pcr_read_dev() using tpm_buf and remove
now unneeded structures from tpm.h

Signed-off-by: Tomas Winkler <tomas.winkler@intel.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>
2018-11-13 13:46:31 +02:00
Tomas Winkler 7aee9c52d7 tpm: tpm1: rewrite tpm1_get_random() using tpm_buf structure
1. Use tpm_buf in tpm1_get_random()
2. Fix comment in tpm_get_random() so it is clear that
the function is expected to return number of random bytes.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.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>
2018-11-13 13:46:31 +02:00
Tomas Winkler 9db7fe187c tpm: factor out tpm_startup function
TPM manual startup is used only from within TPM 1.x or TPM 2.x
code, hence remove tpm_startup() function from tpm-interface.c
and add two static functions implementations tpm1_startup()
and tpm2_startup() into to tpm1-cmd.c and tpm2-cmd.c respectively.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.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>
2018-11-13 13:46:30 +02:00
Tomas Winkler c82a330cec tpm: factor out tpm 1.x pm suspend flow into tpm1-cmd.c
Factor out TPM 1.x suspend flow from tpm-interface.c into a new function
tpm1_pm_suspend() in tpm1-cmd.c

Signed-off-by: Tomas Winkler <tomas.winkler@intel.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>
2018-11-13 13:46:30 +02:00
Tomas Winkler d4a3175632 tpm: move tpm 1.x selftest code from tpm-interface.c tpm1-cmd.c
Move the tpm1 selftest code functions to tpm1-cmd.c
and adjust callers to use the new function names.
 1. tpm_pcr_read_dev() to tpm1_pcr_read_dev().
 2. tpm_continue_selftest() to tpm1_continue_selftest().
 3. tpm_do_selftest() to tpm1_do_selftest()

Signed-off-by: Tomas Winkler <tomas.winkler@intel.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>
2018-11-13 13:46:30 +02:00
Tomas Winkler 433d390f00 tpm: factor out tpm1_get_random into tpm1-cmd.c
Factor out get random implementation from tpm-interface.c
into tpm1_get_random function in tpm1-cmd.c.
No functional changes.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.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>
2018-11-13 13:46:30 +02:00
Tomas Winkler f4d916b72f tpm: move tpm_getcap to tpm1-cmd.c
1. Move tpm_getcap to tpm1-cmd. Rename the function to tpm1_getcap.
2. Remove unused tpm_getcap_header with unused constant
as this functionality is already implemented using tpm_buf construct.

Fixes warning:
drivers/char/tpm/tpm-interface.c:452:38: warning: ‘tpm_getcap_header’ defined but not used [-Wunused-const-variable=]
 static const struct tpm_input_header tpm_getcap_header = {
                                      ^~~~~~~~~~~~~~~~~
3. Drop unused TPM_DIGEST_SIZE. It's already defined in
include/linux/tpm.h

Signed-off-by: Tomas Winkler <tomas.winkler@intel.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>
2018-11-13 13:46:30 +02:00
Tomas Winkler 1ad6640cd6 tpm: move tpm1_pcr_extend to tpm1-cmd.c
Move tpm1_pcr_extend to tpm1-cmd.c and remove
unused pcrextend_header structure and
EXTEND_PCR_RESULT_SIZE and EXTEND_PCR_RESULT_BODY_SIZE
defines.

Fixes warning:
drivers/char/tpm/tpm-interface.c:609:38: warning: ‘pcrextend_header’ defined but not used [-Wunused-const-variable=]
 static const struct tpm_input_header pcrextend_header = {
                                      ^~~~~~~~~~~~~~~~

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Nayna Jain <nayna@linux.ibm.com>
Tested-by: Nayna Jain <nayna@linux.ibm.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2018-11-13 13:46:30 +02:00
Tomas Winkler 70a3199a71 tpm: factor out tpm_get_timeouts()
Factor out tpm_get_timeouts() into tpm2_get_timeouts()
and tpm1_get_timeouts()

Signed-off-by: Tomas Winkler <tomas.winkler@intel.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>
2018-11-13 13:46:30 +02:00
Tomas Winkler d856c00f7d tpm: add tpm_calc_ordinal_duration() wrapper
Add convenient wrapper for ordinal duration computation
to remove boiler plate if else statement over TPM2.

if (chip->flags & TPM_CHIP_FLAG_TPM2)
	tpm2_calc_ordinal_duration(chip, ordinal);
else
	tpm1_calc_ordinal_duration(chip, ordinal);

Signed-off-by: Tomas Winkler <tomas.winkler@intel.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>
2018-11-13 13:46:30 +02:00
Tomas Winkler b2d6e6de00 tpm: factor out tpm 1.x duration calculation to tpm1-cmd.c
Factor out TPM 1.x commands calculation into tpm1-cmd.c file.
and change the prefix from tpm_ to tpm1_.
No functional change is done here.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.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>
2018-11-13 13:46:29 +02:00