diff mbox series

[v4,2/2] selftests: tpm2: Reset the dictionary attack lock

Message ID 20211128041052.1395504-3-stefanb@linux.vnet.ibm.com (mailing list archive)
State New, archived
Headers show
Series selftests: tpm2: Determine available PCR bank | expand

Commit Message

Stefan Berger Nov. 28, 2021, 4:10 a.m. UTC
From: Stefan Berger <stefanb@linux.ibm.com>

Reset the dictionary attack lock to avoid the following types of test
failures after running the test 2 times:

======================================================================
ERROR: test_unseal_with_wrong_policy (tpm2_tests.SmokeTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/root/linux-ima-namespaces/tools/testing/selftests/tpm2/tpm2_tests.py", line 105, in test_unseal_with_wrong_policy
    blob = self.client.seal(self.root_key, data, auth, policy_dig)
  File "/root/linux-ima-namespaces/tools/testing/selftests/tpm2/tpm2.py", line 620, in seal
    rsp = self.send_cmd(cmd)
  File "/root/linux-ima-namespaces/tools/testing/selftests/tpm2/tpm2.py", line 397, in send_cmd
    raise ProtocolError(cc, rc)
tpm2.ProtocolError: TPM_RC_LOCKOUT: cc=0x00000153, rc=0x00000921

Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
---
 tools/testing/selftests/tpm2/tpm2_tests.py | 2 ++
 1 file changed, 2 insertions(+)

Comments

Jarkko Sakkinen Nov. 29, 2021, 11:43 p.m. UTC | #1
On Sat, Nov 27, 2021 at 11:10:52PM -0500, Stefan Berger wrote:
> From: Stefan Berger <stefanb@linux.ibm.com>
> 
> Reset the dictionary attack lock to avoid the following types of test
> failures after running the test 2 times:
> 
> ======================================================================
> ERROR: test_unseal_with_wrong_policy (tpm2_tests.SmokeTest)
> ----------------------------------------------------------------------
> Traceback (most recent call last):
>   File "/root/linux-ima-namespaces/tools/testing/selftests/tpm2/tpm2_tests.py", line 105, in test_unseal_with_wrong_policy
>     blob = self.client.seal(self.root_key, data, auth, policy_dig)
>   File "/root/linux-ima-namespaces/tools/testing/selftests/tpm2/tpm2.py", line 620, in seal
>     rsp = self.send_cmd(cmd)
>   File "/root/linux-ima-namespaces/tools/testing/selftests/tpm2/tpm2.py", line 397, in send_cmd
>     raise ProtocolError(cc, rc)
> tpm2.ProtocolError: TPM_RC_LOCKOUT: cc=0x00000153, rc=0x00000921
> 
> Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
> ---
>  tools/testing/selftests/tpm2/tpm2_tests.py | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/tools/testing/selftests/tpm2/tpm2_tests.py b/tools/testing/selftests/tpm2/tpm2_tests.py
> index e63a37819978..ad6f54c01adf 100644
> --- a/tools/testing/selftests/tpm2/tpm2_tests.py
> +++ b/tools/testing/selftests/tpm2/tpm2_tests.py
> @@ -139,6 +139,8 @@ class SmokeTest(unittest.TestCase):
>          except:
>              self.client.flush_context(handle)
>              raise
> +        finally:
> +            self.client.reset_da_lock()
>  
>          self.assertEqual(rc, tpm2.TPM2_RC_POLICY_FAIL)
>  
> -- 
> 2.31.1
> 

I don't agree with this as a DA lock has legit use. This would be adequate
for systems dedicated for kernel testing only.

We could make this available in the folder where TPM2 tests are:

https://git.kernel.org/pub/scm/linux/kernel/git/jarkko/tpm2-scripts.git/tree/tpm2-reset-da-lock

/Jarkko
Stefan Berger Nov. 30, 2021, 12:26 a.m. UTC | #2
On 11/29/21 18:43, Jarkko Sakkinen wrote:
> On Sat, Nov 27, 2021 at 11:10:52PM -0500, Stefan Berger wrote:
>> From: Stefan Berger <stefanb@linux.ibm.com>
>>
>> Reset the dictionary attack lock to avoid the following types of test
>> failures after running the test 2 times:
>>
>> ======================================================================
>> ERROR: test_unseal_with_wrong_policy (tpm2_tests.SmokeTest)
>> ----------------------------------------------------------------------
>> Traceback (most recent call last):
>>    File "/root/linux-ima-namespaces/tools/testing/selftests/tpm2/tpm2_tests.py", line 105, in test_unseal_with_wrong_policy
>>      blob = self.client.seal(self.root_key, data, auth, policy_dig)
>>    File "/root/linux-ima-namespaces/tools/testing/selftests/tpm2/tpm2.py", line 620, in seal
>>      rsp = self.send_cmd(cmd)
>>    File "/root/linux-ima-namespaces/tools/testing/selftests/tpm2/tpm2.py", line 397, in send_cmd
>>      raise ProtocolError(cc, rc)
>> tpm2.ProtocolError: TPM_RC_LOCKOUT: cc=0x00000153, rc=0x00000921
>>
>> Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
>> ---
>>   tools/testing/selftests/tpm2/tpm2_tests.py | 2 ++
>>   1 file changed, 2 insertions(+)
>>
>> diff --git a/tools/testing/selftests/tpm2/tpm2_tests.py b/tools/testing/selftests/tpm2/tpm2_tests.py
>> index e63a37819978..ad6f54c01adf 100644
>> --- a/tools/testing/selftests/tpm2/tpm2_tests.py
>> +++ b/tools/testing/selftests/tpm2/tpm2_tests.py
>> @@ -139,6 +139,8 @@ class SmokeTest(unittest.TestCase):
>>           except:
>>               self.client.flush_context(handle)
>>               raise
>> +        finally:
>> +            self.client.reset_da_lock()
>>   
>>           self.assertEqual(rc, tpm2.TPM2_RC_POLICY_FAIL)
>>   
>> -- 
>> 2.31.1
>>
> I don't agree with this as a DA lock has legit use. This would be adequate
> for systems dedicated for kernel testing only.

The problem is this particular test case I am patching here causes the 
above test failures upon rerun. We are testing the driver here 
presumably and not the TPM2, so I think we should leave the TPM2 as 
cleaned up as possible, thus my suggestion is to reset the DA lock and 
we won't hear any complaints after that.


> We could make this available in the folder where TPM2 tests are:
>
> https://git.kernel.org/pub/scm/linux/kernel/git/jarkko/tpm2-scripts.git/tree/tpm2-reset-da-lock


The tss packages also have command line tools to reset the DA lock, but 
it shouldn't be necessary to use them after running a **driver** test case.


    stefan


>
> /Jarkko
Jarkko Sakkinen Dec. 1, 2021, 10:16 a.m. UTC | #3
On Mon, Nov 29, 2021 at 07:26:12PM -0500, Stefan Berger wrote:
> 
> On 11/29/21 18:43, Jarkko Sakkinen wrote:
> > On Sat, Nov 27, 2021 at 11:10:52PM -0500, Stefan Berger wrote:
> > > From: Stefan Berger <stefanb@linux.ibm.com>
> > > 
> > > Reset the dictionary attack lock to avoid the following types of test
> > > failures after running the test 2 times:
> > > 
> > > ======================================================================
> > > ERROR: test_unseal_with_wrong_policy (tpm2_tests.SmokeTest)
> > > ----------------------------------------------------------------------
> > > Traceback (most recent call last):
> > >    File "/root/linux-ima-namespaces/tools/testing/selftests/tpm2/tpm2_tests.py", line 105, in test_unseal_with_wrong_policy
> > >      blob = self.client.seal(self.root_key, data, auth, policy_dig)
> > >    File "/root/linux-ima-namespaces/tools/testing/selftests/tpm2/tpm2.py", line 620, in seal
> > >      rsp = self.send_cmd(cmd)
> > >    File "/root/linux-ima-namespaces/tools/testing/selftests/tpm2/tpm2.py", line 397, in send_cmd
> > >      raise ProtocolError(cc, rc)
> > > tpm2.ProtocolError: TPM_RC_LOCKOUT: cc=0x00000153, rc=0x00000921
> > > 
> > > Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
> > > ---
> > >   tools/testing/selftests/tpm2/tpm2_tests.py | 2 ++
> > >   1 file changed, 2 insertions(+)
> > > 
> > > diff --git a/tools/testing/selftests/tpm2/tpm2_tests.py b/tools/testing/selftests/tpm2/tpm2_tests.py
> > > index e63a37819978..ad6f54c01adf 100644
> > > --- a/tools/testing/selftests/tpm2/tpm2_tests.py
> > > +++ b/tools/testing/selftests/tpm2/tpm2_tests.py
> > > @@ -139,6 +139,8 @@ class SmokeTest(unittest.TestCase):
> > >           except:
> > >               self.client.flush_context(handle)
> > >               raise
> > > +        finally:
> > > +            self.client.reset_da_lock()
> > >           self.assertEqual(rc, tpm2.TPM2_RC_POLICY_FAIL)
> > > -- 
> > > 2.31.1
> > > 
> > I don't agree with this as a DA lock has legit use. This would be adequate
> > for systems dedicated for kernel testing only.
> 
> The problem is this particular test case I am patching here causes the above
> test failures upon rerun. We are testing the driver here presumably and not
> the TPM2, so I think we should leave the TPM2 as cleaned up as possible,
> thus my suggestion is to reset the DA lock and we won't hear any complaints
> after that.

Ok.

> > We could make this available in the folder where TPM2 tests are:
> > 
> > https://git.kernel.org/pub/scm/linux/kernel/git/jarkko/tpm2-scripts.git/tree/tpm2-reset-da-lock
> 
> 
> The tss packages also have command line tools to reset the DA lock, but it
> shouldn't be necessary to use them after running a **driver** test case.

If you speak about TSS, please alway say which one :-)

Adding non-volatile state changes explicitly is to a test case is both
intrusive and wrong. These type of choices are not to be done in the
test case implementation for sure.

An improvement that does not add extra side-effect, would be to read the
TPM_PT_LOCKOUT_COUNTER and roll back with a proper error message for the
lockout condition.

You can also configure the maximum number of tries up to (2 << 31) - 1
= 4294967295 with TPM2_DictionaryAttackParameters.

/Jarkko
Jarkko Sakkinen Dec. 1, 2021, 10:19 a.m. UTC | #4
On Wed, Dec 01, 2021 at 12:16:11PM +0200, Jarkko Sakkinen wrote:
> On Mon, Nov 29, 2021 at 07:26:12PM -0500, Stefan Berger wrote:
> > 
> > On 11/29/21 18:43, Jarkko Sakkinen wrote:
> > > On Sat, Nov 27, 2021 at 11:10:52PM -0500, Stefan Berger wrote:
> > > > From: Stefan Berger <stefanb@linux.ibm.com>
> > > > 
> > > > Reset the dictionary attack lock to avoid the following types of test
> > > > failures after running the test 2 times:
> > > > 
> > > > ======================================================================
> > > > ERROR: test_unseal_with_wrong_policy (tpm2_tests.SmokeTest)
> > > > ----------------------------------------------------------------------
> > > > Traceback (most recent call last):
> > > >    File "/root/linux-ima-namespaces/tools/testing/selftests/tpm2/tpm2_tests.py", line 105, in test_unseal_with_wrong_policy
> > > >      blob = self.client.seal(self.root_key, data, auth, policy_dig)
> > > >    File "/root/linux-ima-namespaces/tools/testing/selftests/tpm2/tpm2.py", line 620, in seal
> > > >      rsp = self.send_cmd(cmd)
> > > >    File "/root/linux-ima-namespaces/tools/testing/selftests/tpm2/tpm2.py", line 397, in send_cmd
> > > >      raise ProtocolError(cc, rc)
> > > > tpm2.ProtocolError: TPM_RC_LOCKOUT: cc=0x00000153, rc=0x00000921
> > > > 
> > > > Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
> > > > ---
> > > >   tools/testing/selftests/tpm2/tpm2_tests.py | 2 ++
> > > >   1 file changed, 2 insertions(+)
> > > > 
> > > > diff --git a/tools/testing/selftests/tpm2/tpm2_tests.py b/tools/testing/selftests/tpm2/tpm2_tests.py
> > > > index e63a37819978..ad6f54c01adf 100644
> > > > --- a/tools/testing/selftests/tpm2/tpm2_tests.py
> > > > +++ b/tools/testing/selftests/tpm2/tpm2_tests.py
> > > > @@ -139,6 +139,8 @@ class SmokeTest(unittest.TestCase):
> > > >           except:
> > > >               self.client.flush_context(handle)
> > > >               raise
> > > > +        finally:
> > > > +            self.client.reset_da_lock()
> > > >           self.assertEqual(rc, tpm2.TPM2_RC_POLICY_FAIL)
> > > > -- 
> > > > 2.31.1
> > > > 
> > > I don't agree with this as a DA lock has legit use. This would be adequate
> > > for systems dedicated for kernel testing only.
> > 
> > The problem is this particular test case I am patching here causes the above
> > test failures upon rerun. We are testing the driver here presumably and not
> > the TPM2, so I think we should leave the TPM2 as cleaned up as possible,
> > thus my suggestion is to reset the DA lock and we won't hear any complaints
> > after that.
> 
> Ok.
> 
> > > We could make this available in the folder where TPM2 tests are:
> > > 
> > > https://git.kernel.org/pub/scm/linux/kernel/git/jarkko/tpm2-scripts.git/tree/tpm2-reset-da-lock
> > 
> > 
> > The tss packages also have command line tools to reset the DA lock, but it
> > shouldn't be necessary to use them after running a **driver** test case.
> 
> If you speak about TSS, please alway say which one :-)
> 
> Adding non-volatile state changes explicitly is to a test case is both

A typo, should be:

"Adding non-volatile state changes explicitly to a test case is both"

/Jarkko
Stefan Berger Dec. 1, 2021, 2:52 p.m. UTC | #5
On 12/1/21 05:16, Jarkko Sakkinen wrote:

> On Mon, Nov 29, 2021 at 07:26:12PM -0500, Stefan Berger wrote:
>> On 11/29/21 18:43, Jarkko Sakkinen wrote:
>>> On Sat, Nov 27, 2021 at 11:10:52PM -0500, Stefan Berger wrote:
>>>> From: Stefan Berger <stefanb@linux.ibm.com>
>>>>
>>>> Reset the dictionary attack lock to avoid the following types of test
>>>> failures after running the test 2 times:
>>>>
>>>> ======================================================================
>>>> ERROR: test_unseal_with_wrong_policy (tpm2_tests.SmokeTest)
>>>> ----------------------------------------------------------------------
>>>> Traceback (most recent call last):
>>>>     File "/root/linux-ima-namespaces/tools/testing/selftests/tpm2/tpm2_tests.py", line 105, in test_unseal_with_wrong_policy
>>>>       blob = self.client.seal(self.root_key, data, auth, policy_dig)
>>>>     File "/root/linux-ima-namespaces/tools/testing/selftests/tpm2/tpm2.py", line 620, in seal
>>>>       rsp = self.send_cmd(cmd)
>>>>     File "/root/linux-ima-namespaces/tools/testing/selftests/tpm2/tpm2.py", line 397, in send_cmd
>>>>       raise ProtocolError(cc, rc)
>>>> tpm2.ProtocolError: TPM_RC_LOCKOUT: cc=0x00000153, rc=0x00000921
>>>>
>>>> Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
>>>> ---
>>>>    tools/testing/selftests/tpm2/tpm2_tests.py | 2 ++
>>>>    1 file changed, 2 insertions(+)
>>>>
>>>> diff --git a/tools/testing/selftests/tpm2/tpm2_tests.py b/tools/testing/selftests/tpm2/tpm2_tests.py
>>>> index e63a37819978..ad6f54c01adf 100644
>>>> --- a/tools/testing/selftests/tpm2/tpm2_tests.py
>>>> +++ b/tools/testing/selftests/tpm2/tpm2_tests.py
>>>> @@ -139,6 +139,8 @@ class SmokeTest(unittest.TestCase):
>>>>            except:
>>>>                self.client.flush_context(handle)
>>>>                raise
>>>> +        finally:
>>>> +            self.client.reset_da_lock()
>>>>            self.assertEqual(rc, tpm2.TPM2_RC_POLICY_FAIL)
>>>> -- 
>>>> 2.31.1
>>>>
>>> I don't agree with this as a DA lock has legit use. This would be adequate
>>> for systems dedicated for kernel testing only.
>> The problem is this particular test case I am patching here causes the above
>> test failures upon rerun. We are testing the driver here presumably and not
>> the TPM2, so I think we should leave the TPM2 as cleaned up as possible,
>> thus my suggestion is to reset the DA lock and we won't hear any complaints
>> after that.
>
>> The tss packages also have command line tools to reset the DA lock, but it
>> shouldn't be necessary to use them after running a **driver** test case.
> If you speak about TSS, please alway say which one :-)

packages : both

tpm2_dictionarylockout -c [ -p password ]

tssdictionaryattacklockreset [-pwd password]


>
> Adding non-volatile state changes explicitly is to a test case is both
> intrusive and wrong. These type of choices are not to be done in the
> test case implementation for sure.

I drop this patch because if someone changed the password the lock reset 
will not work as expected.

One can also argue with having a test case that triggers a failure 
condition in the TPM2 is both intrusive and wrong. That said, the 
offending test cases should probably not even exist, especially since 
they test a user's knowledge about the device afterwards...


>
> An improvement that does not add extra side-effect, would be to read the
> TPM_PT_LOCKOUT_COUNTER and roll back with a proper error message for the
> lockout condition.
>
> You can also configure the maximum number of tries up to (2 << 31) - 1
> = 4294967295 with TPM2_DictionaryAttackParameters...

... which I think the user of a device driver test should not have to do.


   Stefan

>
> /Jarkko
diff mbox series

Patch

diff --git a/tools/testing/selftests/tpm2/tpm2_tests.py b/tools/testing/selftests/tpm2/tpm2_tests.py
index e63a37819978..ad6f54c01adf 100644
--- a/tools/testing/selftests/tpm2/tpm2_tests.py
+++ b/tools/testing/selftests/tpm2/tpm2_tests.py
@@ -139,6 +139,8 @@  class SmokeTest(unittest.TestCase):
         except:
             self.client.flush_context(handle)
             raise
+        finally:
+            self.client.reset_da_lock()
 
         self.assertEqual(rc, tpm2.TPM2_RC_POLICY_FAIL)