From mboxrd@z Thu Jan 1 00:00:00 1970 From: Javier Martinez Canillas Subject: Re: [tpmdd-devel] [PATCH v3 0/5] Call GetEventLog before ExitBootServices Date: Tue, 26 Sep 2017 13:17:27 +0200 Message-ID: References: <20170920081340.7413-1-tweek@google.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20170920081340.7413-1-tweek-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org> Content-Language: en-US Sender: linux-efi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Thiebaud Weksteen , linux-efi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-integrity-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, tpmdd-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Cc: ard.biesheuvel-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, matt-mF/unelCI9GS6iBeEJttW/XRex20P6io@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, jarkko.sakkinen-VuQAYsv1563Yd54FQh9/CA@public.gmane.org, jgunthorpe-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org, mjg59-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org List-Id: tpmdd-devel@lists.sourceforge.net Archived-At: List-Archive: List-Post: On 09/20/2017 10:13 AM, Thiebaud Weksteen via tpmdd-devel wrote: > With TPM 1.2, the ACPI table ("TCPA") has two fields to recover the Event > Log Area (LAML and LASA). These logs are useful to understand and rebuild > the final values of PCRs. > > With TPM 2.0, the ACPI table ("TPM2") does not contain these fields > anymore. The recommended method is now to call the GetEventLog EFI > protocol before ExitBootServices. > > Implement this method within the EFI stub and create a copy of the logs > for the TPM device using a Linux-specific EFI configuration table > (LINUX_EFI_TPM_EVENT_LOG). This will create > /sys/kernel/security/tpm0/binary_bios_measurements for TPM 2.0 devices > (similarly to the current behaviour for TPM 1.2 devices). > > Two formats for the log entries exist: TPM 1.2 (SHA1) and TPM 2.0 (Crypto > Agile). This patch set only retrieves the first type of logs. The second > type will be implemented in a subsequent patch set. > > According to the specifications[1], once GetEventLog has been called, > future events shall be stored in a separate EFI configuration table > (EFI_TCG2_FINAL_EVENTS_TABLE). Events stored in this table are not > processed in this patch set as they are stored in the Crypto Agile format. > These could eventually be merged with the new table for a unified view > of the logs from userspace. > > [1] TCG EFI Protocol Specification, Revision 00.13, March 30, 2016 > https://trustedcomputinggroup.org/wp-content/uploads/EFI-Protocol-Specification-rev13-160330final.pdf > > ------------------------------------------------------------------------------- > > Patchset Changelog: > > Version 3: > - Move event log providers (acpi and of) to tpm_eventlog_*.c > - Move efi changes from PATCH 3 to PATCH 2 > - Change return value of tpm_read_log_acpi and tpm_read_log_of > - Change iounmap to memunmap calls > - Use log_tbl as variable name for consistency > - Fix kbuild failures > Thanks for addressing the things I pointed out. For the whole patch-set: Reviewed-by: Javier Martinez Canillas Tested-by: Javier Martinez Canillas Best regards, -- Javier Martinez Canillas Software Engineer - Desktop Hardware Enablement Red Hat