I don't see anything wrong with what you're trying to do.

Can you switch from the hardware TPM to the SW TPM?

You can then get a trace of the TPM internals.  This would tell you 
whether the problem is in the tools, in the TSS, or perhaps even in the TPM.

I can't imagine debugging any application with the HW TPM, but of course 
I wrote the SW TPM.  :-)

On 1/26/2014 3:18 PM, Andreas Thienemann wrote:
> Hi,
>
> I've been trying to create a NVRAM area I can keep a key in which is
> sealed to certain PCRs.
>
> If I have the following setting, I am being asked for the nvram password
> before being able to read the nvram area.
>
> [root@foo ~]# tpm_nvinfo -i 2
> NVRAM index   : 0x00000002 (2)
> PCR read  selection:
>    PCRs    : 4, 5, 8, 9, 12, 14
>    Localities   : ALL
>    Hash    : 51522172b46ed13a34ca45f445472291c9675ef5
> PCR write selection:
>    Localities   : ALL
> Permissions   : 0x0040004 (AUTHREAD|AUTHWRITE)
> bReadSTClear  : FALSE
> bWriteSTClear : FALSE
> bWriteDefine  : FALSE
> Size          : 32 (0x20)
>
> [root@foo ~]#
>
> If my PCRs change I am unable to access this nvram area with my nvram
> password. So far so good.
>
> I am now trying to have access to this nvram area without having to type
> in any passwords as long as the PCR registers are the same.
>
> When defining the permission as only AUTHWRITE I do have access to the
> nvnram area without a password but it seems to me that the nvram area is
> not sealed anymore. If the PCRs change, I can still read out the data
> from the nvram area which shouldn't be the case.
>
> [root@foo ~]# tpm_nvread -i 2 > /dev/null
> [root@foo ~]# echo $?
> 0
> [root@foo ~]# tpm_nvinfo -i 2
> NVRAM index   : 0x00000002 (2)
> PCR read  selection:
>    PCRs    : 4, 5, 8, 9, 12, 14
>    Localities   : ALL
>    Hash    : 51522172b46ed13a34ca45f445472291c9675ef5
> PCR write selection:
>    Localities   : ALL
> Permissions   : 0x00000004 (AUTHWRITE)
> bReadSTClear  : FALSE
> bWriteSTClear : FALSE
> bWriteDefine  : FALSE
> Size          : 32 (0x20)
>
> [root@foo ~]#
>
> Any idea how to achieve what I want?

>



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