[PATCH 1/3] tpm: Disable TCG_TPM2_HMAC by default

[Vitor Soares]

On Tue, 2024-05-21 at 08:33 -0400, James Bottomley wrote:
> On Tue, 2024-05-21 at 10:10 +0300, Jarkko Sakkinen wrote:
> > This benchmark could be done in user space using /dev/tpm0.
> 
> Let's actually try that.  If you have the ibmtss installed, the command
> to time primary key generation from userspace on your tpm is
> 
> time tsscreateprimary -hi n -ecc nistp256
> 
> 
> And just for chuckles and grins, try it in the owner hierarchy as well
> (sometimes slow TPMs cache this)
> 
> time tsscreateprimary -hi o -ecc nistp256
> 
> And if you have tpm2 tools, the above commands should be:
> 
> time tpm2_createprimary -C n -G ecc256
> time tpm2_createprimary -C o -G ecc256
> 
> James
> 
> 

Testing on an arm64 platform I get the following results.

hmac disabled:
  time modprobe tpm_tis_spi
  real    0m2.776s
  user    0m0.006s
  sys     0m0.015s

  time tpm2_createprimary -C n -G ecc256
  real    0m0.686s
  user    0m0.044s
  sys     0m0.025s

  time tpm2_createprimary -C o -G ecc256
  real    0m0.638s
  user    0m0.048s
  sys     0m0.009s


hmac enabled:
  time modprobe tpm_tis_spi
  real    8m5.840s
  user    0m0.005s
  sys     0m0.018s


  time tpm2_createprimary -C n -G ecc256
  real    5m27.678s
  user    0m0.059s
  sys     0m0.009s

  (after first command)
  real    0m0.395s
  user    0m0.040s
  sys     0m0.015s

  time tpm2_createprimary -C o -G ecc256
  real    0m0.418s
  user    0m0.049s
  sys     0m0.009s

hmac enabled + patches applied
  time modprobe tpm_tis_spi
  real    8m6.663s
  user    0m0.000s
  sys     0m0.021s


  time tpm2_createprimary -C n -G ecc256
  real    7m24.662s
  user    0m0.048s
  sys     0m0.022s

  (after first command)
  real    0m0.395s
  user    0m0.047s
  sys     0m0.009s

  time tpm2_createprimary -C o -G ecc256
  real    0m0.404s
  user    0m0.046s
  sys     0m0.012s


Regards,
Vitor Soares