lkml.org 
[lkml]   [2020]   [Mar]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [RFC PATCH 03/12] x86: Add early SHA support for Secure Launch early measurements
On Wed, Mar 25, 2020 at 12:43 PM Ross Philipson
<ross.philipson@oracle.com> wrote:
>
> From: "Daniel P. Smith" <dpsmith@apertussolutions.com>
>
> The SHA algorithms are necessary to measure configuration information into
> the TPM as early as possible before using the values. This implementation
> uses the established approach of #including the SHA libraries directly in
> the code since the compressed kernel is not uncompressed at this point.
>
> The SHA1 code here has its origins in the code in
> include/crypto/sha1_base.h. That code could not be pulled directly into
> the setup portion of the compressed kernel because of other dependencies
> it pulls in. So this is a modified copy of that code that still leverages
> the core SHA1 algorithm.
>
> Signed-off-by: Daniel P. Smith <dpsmith@apertussolutions.com>
> ---
> arch/x86/Kconfig | 24 +++
> arch/x86/boot/compressed/Makefile | 4 +
> arch/x86/boot/compressed/early_sha1.c | 104 ++++++++++++
> arch/x86/boot/compressed/early_sha1.h | 17 ++
> arch/x86/boot/compressed/early_sha256.c | 6 +
> arch/x86/boot/compressed/early_sha512.c | 6 +
> include/linux/sha512.h | 21 +++
> lib/sha1.c | 4 +
> lib/sha512.c | 209 ++++++++++++++++++++++++
> 9 files changed, 395 insertions(+)
> create mode 100644 arch/x86/boot/compressed/early_sha1.c
> create mode 100644 arch/x86/boot/compressed/early_sha1.h
> create mode 100644 arch/x86/boot/compressed/early_sha256.c
> create mode 100644 arch/x86/boot/compressed/early_sha512.c
> create mode 100644 include/linux/sha512.h
> create mode 100644 lib/sha512.c
>
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index 7f3406a9948b..f37057d3ce9f 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -2025,6 +2025,30 @@ config SECURE_LAUNCH
> of all the modules and configuration information used for
> boooting the operating system.
>
> +choice
> + prompt "Select Secure Launch Algorithm for TPM2"
> + depends on SECURE_LAUNCH
> +
> +config SECURE_LAUNCH_SHA1
> + bool "Secure Launch TPM2 SHA1"
> + help
> + When using Secure Launch and TPM2 is present, use SHA1 hash
> + algorithm for measurements.
> +

I'm surprised this is supported at all. Why allow SHA1?

\
 
 \ /
  Last update: 2020-03-26 04:45    [W:0.097 / U:1.928 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site