From: Bruno Meneguele <bmeneg@redhat.com>
To: Stefan Berger <stefanb@linux.ibm.com>
Cc: Maurizio Drocco <maurizio.drocco@ibm.com>,
zohar@linux.ibm.com, Silviu.Vlasceanu@huawei.com,
dmitry.kasatkin@gmail.com, jejb@linux.ibm.com, jmorris@namei.org,
linux-integrity@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-security-module@vger.kernel.org,
mdrocco@linux.vnet.ibm.com, roberto.sassu@huawei.com,
serge@hallyn.com
Subject: Re: [PATCH v2] ima_evm_utils: extended calc_bootaggr to PCRs 8 - 9
Date: Wed, 24 Jun 2020 18:33:45 -0300 [thread overview]
Message-ID: <20200624213345.GB2639@glitch> (raw)
In-Reply-To: <92a0d170-8157-476b-8083-ae567b11f364@linux.ibm.com>
[-- Attachment #1: Type: text/plain, Size: 2663 bytes --]
On Wed, Jun 24, 2020 at 05:17:52PM -0400, Stefan Berger wrote:
> On 6/23/20 2:13 PM, Bruno Meneguele wrote:
> > On Tue, Jun 23, 2020 at 02:01:22PM -0400, Maurizio Drocco wrote:
> > > From: Maurizio <maurizio.drocco@ibm.com>
> > >
> > > If PCRs 8 - 9 are set (i.e. not all-zeros), cal_bootaggr should include
> > > them into the digest.
>
>
> Wouldn't you have to check for not all-zeros in your code?
>
boot_aggregate in kernel, after the following patch be applied:
https://lkml.org/lkml/2020/6/23/833
is calculated regardless PCR 8 & 9 being zero or not.
Thus evmctl is only reflecting the same behavior.
I think it would be worth changing the commit log here.
>
> Stefan
>
>
> > >
> > > Signed-off-by: Maurizio Drocco <maurizio.drocco@ibm.com>
> > > ---
> > > Changelog:
> > > v2:
> > > - Always include PCRs 8 & 9 to non-sha1 hashes
> > > v1:
> > > - Include non-zero PCRs 8 & 9 to boot aggregates
> > >
> > > src/evmctl.c | 15 +++++++++++++--
> > > 1 file changed, 13 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/src/evmctl.c b/src/evmctl.c
> > > index 1d065ce..46b7092 100644
> > > --- a/src/evmctl.c
> > > +++ b/src/evmctl.c
> > > @@ -1930,6 +1930,16 @@ static void calc_bootaggr(struct tpm_bank_info *bank)
> > > }
> > > }
> > > + if (strcmp(bank->algo_name, "sha1") != 0) {
> > > + for (i = 8; i < 10; i++) {
> > > + err = EVP_DigestUpdate(pctx, bank->pcr[i], bank->digest_size);
> > > + if (!err) {
> > > + log_err("EVP_DigestUpdate() failed\n");
> > > + return;
> > > + }
> > > + }
> > > + }
> > > +
> > > err = EVP_DigestFinal(pctx, bank->digest, &mdlen);
> > > if (!err) {
> > > log_err("EVP_DigestFinal() failed\n");
> > > @@ -1972,8 +1982,9 @@ static int append_bootaggr(char *bootaggr, struct tpm_bank_info *tpm_banks)
> > > /*
> > > * The IMA measurement list boot_aggregate is the link between the preboot
> > > * event log and the IMA measurement list. Read and calculate all the
> > > - * possible per TPM bank boot_aggregate digests based on the existing
> > > - * PCRs 0 - 7 to validate against the IMA boot_aggregate record.
> > > + * possible per TPM bank boot_aggregate digests based on the existing PCRs
> > > + * 0 - 9 to validate against the IMA boot_aggregate record. If the digest
> > > + * algorithm is SHA1, only PCRs 0 - 7 are considered to avoid ambiguity.
> > > */
> > > static int cmd_ima_bootaggr(struct command *cmd)
> > > {
> > > --
> > > 2.17.1
> > >
> > Reviewed-by: Bruno Meneguele <bmeneg@redhat.com>
> >
>
--
bmeneg
PGP Key: http://bmeneg.com/pubkey.txt
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 488 bytes --]
next prev parent reply other threads:[~2020-06-24 21:34 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-06-11 19:54 [PATCH] extend IMA boot_aggregate with kernel measurements Maurizio Drocco
2020-06-12 0:29 ` Mimi Zohar
2020-06-12 14:38 ` Maurizio Drocco
2020-06-12 15:11 ` Roberto Sassu
2020-06-12 17:14 ` James Bottomley
2020-06-16 17:29 ` Roberto Sassu
2020-06-16 18:11 ` Mimi Zohar
2020-06-18 12:38 ` Roberto Sassu
2020-06-18 20:11 ` Maurizio Drocco
2020-06-18 20:11 ` [PATCH] ima_evm_utils: extended calc_bootaggr to PCRs 8 - 9 Maurizio Drocco
2020-06-22 20:14 ` Mimi Zohar
2020-06-22 4:50 ` [PATCH] ima: extend boot_aggregate with kernel measurements Maurizio Drocco
2020-06-23 14:03 ` Mimi Zohar
2020-06-23 15:57 ` [PATCH v4] " Maurizio Drocco
2020-06-23 18:53 ` Bruno Meneguele
2020-06-23 18:01 ` [PATCH v2] ima_evm_utils: extended calc_bootaggr to PCRs 8 - 9 Maurizio Drocco
2020-06-23 18:13 ` Bruno Meneguele
2020-06-24 21:17 ` Stefan Berger
2020-06-24 21:33 ` [PATCH] " Maurizio Drocco
2020-06-24 21:33 ` Bruno Meneguele [this message]
2020-06-24 21:35 ` [PATCH v3] " Maurizio Drocco
2020-06-24 21:50 ` Bruno Meneguele
2020-06-12 4:47 ` [PATCH] extend IMA boot_aggregate with kernel measurements kernel test robot
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=20200624213345.GB2639@glitch \
--to=bmeneg@redhat.com \
--cc=Silviu.Vlasceanu@huawei.com \
--cc=dmitry.kasatkin@gmail.com \
--cc=jejb@linux.ibm.com \
--cc=jmorris@namei.org \
--cc=linux-integrity@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-security-module@vger.kernel.org \
--cc=maurizio.drocco@ibm.com \
--cc=mdrocco@linux.vnet.ibm.com \
--cc=roberto.sassu@huawei.com \
--cc=serge@hallyn.com \
--cc=stefanb@linux.ibm.com \
--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).