From: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
To: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: linux-integrity@vger.kernel.org, Mimi Zohar <zohar@linux.ibm.com>,
David Woodhouse <dwmw2@infradead.org>,
keyrings@vger.kernel.org
Subject: Re: [PATCH v6 6/6] security: keys: trusted: implement counter/timer policy
Date: Tue, 3 Mar 2020 22:08:20 +0200 [thread overview]
Message-ID: <20200303200820.GE5775@linux.intel.com> (raw)
In-Reply-To: <20200302122759.5204-7-James.Bottomley@HansenPartnership.com>
On Mon, Mar 02, 2020 at 07:27:59AM -0500, James Bottomley wrote:
> This is actually a generic policy allowing a range of comparisons
> against any value set in the TPM Clock, which includes things like the
> reset count, a monotonic millisecond count and the restart count. The
> most useful comparison is against the millisecond count for expiring
> keys. However, you have to remember that currently Linux doesn't try
> to sync the epoch timer with the TPM, so the expiration is actually
> measured in how long the TPM itself has been powered on ... the TPM
> timer doesn't count while the system is powered down. The millisecond
> counter is a u64 quantity found at offset 8 in the timer structure,
> and the <= comparision operand is 9, so a policy set to expire after the
> TPM has been up for 100 seconds would look like
>
> 0000016d00000000000f424000080009
>
> Where 0x16d is the counter timer policy code and 0xf4240 is 100 000 in
> hex.
>
> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
It is techincally possible to merge 1-5 without this and have something
functional?
/Jarkko
next prev parent reply other threads:[~2020-03-03 20:08 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-03-02 12:27 [PATCH v6 0/6] TPM 2.0 trusted keys with attached policy James Bottomley
2020-03-02 12:27 ` [PATCH v6 1/6] lib: add ASN.1 encoder James Bottomley
2020-03-03 19:22 ` Jarkko Sakkinen
2020-03-03 20:49 ` James Bottomley
2020-03-03 21:31 ` Jarkko Sakkinen
2020-03-02 12:27 ` [PATCH v6 2/6] oid_registry: Add TCG defined OIDS for TPM keys James Bottomley
2020-03-03 19:24 ` Jarkko Sakkinen
2020-03-02 12:27 ` [PATCH v6 3/6] security: keys: trusted: fix TPM2 authorizations James Bottomley
2020-03-03 19:33 ` Jarkko Sakkinen
2020-03-03 20:39 ` James Bottomley
2020-03-03 21:32 ` Jarkko Sakkinen
2020-03-02 12:27 ` [PATCH v6 4/6] security: keys: trusted: use ASN.1 TPM2 key format for the blobs James Bottomley
2020-03-03 20:06 ` Jarkko Sakkinen
2020-03-03 20:42 ` James Bottomley
2020-03-03 21:20 ` Jarkko Sakkinen
2020-03-02 12:27 ` [PATCH v6 5/6] security: keys: trusted: add ability to specify arbitrary policy James Bottomley
2020-03-02 12:27 ` [PATCH v6 6/6] security: keys: trusted: implement counter/timer policy James Bottomley
2020-03-03 20:08 ` Jarkko Sakkinen [this message]
2020-03-03 20:40 ` James Bottomley
2020-03-03 21:20 ` Jarkko Sakkinen
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200303200820.GE5775@linux.intel.com \
--to=jarkko.sakkinen@linux.intel.com \
--cc=James.Bottomley@HansenPartnership.com \
--cc=dwmw2@infradead.org \
--cc=keyrings@vger.kernel.org \
--cc=linux-integrity@vger.kernel.org \
--cc=zohar@linux.ibm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).