Re: [PATCH v2 3/4] ima_tpm.sh: Fix calculating boot aggregate

[Petr Vorel <pvorel@suse.cz>]

> On Tue, 2020-09-29 at 14:17 +0200, Petr Vorel wrote:
> > Hi,

> > >  test1()
> > >  {
> > >  	tst_res TINFO "verify boot aggregate"

> > > -	local zero="0000000000000000000000000000000000000000"
> > >  	local tpm_bios="$SECURITYFS/tpm0/binary_bios_measurements"
> > > -	local ima_measurements="$ASCII_MEASUREMENTS"
> > > -	local boot_aggregate boot_hash line
> > > +	local cmd="evmctl ima_boot_aggregate"
> > > +	local boot_aggregate cmd zero

> > > -	# IMA boot aggregate
> > > -	read line < $ima_measurements
> > > -	boot_hash=$(echo $line | awk '{print $(NF-1)}' | cut -d':' -f2)
> > > +	if [ "$MISSING_EVMCTL" = 1 ]; then
> > > +		if [ -f "$tpm_bios" ]; then
> > I leaved this error during rebase:
> > if [ ! -f "$tpm_bios" ]; then

> > I'm still investigating corner case issue when
> > /sys/kernel/security/tpm0/binary_bios_measurements
> > is not presented (mostly when no TPM device, thus IMA "TPM-bypass" code being
> > used, but sometimes also for TPM 2.0 which does not export event log).

> There's another case as well.  On one of my test systems with a TPM 2.0
> chip, but without secure boot enabled, the binary_bios_measurements
> exists, but it can't be accessed.  dmesg contains a secure boot status
> line.
So you can view binary_bios_measurements with ls, but don't have permission to
read. Interesting.

> Mimi

Kind regards,
Petr