2024-11-11 Alignment Meeting

[nnooney]

• Date: Monday November 11
• Time: 5pm CET / 8 AM PT
• Meeting Link: https://us06web.zoom.us/j/82359538490?pwd=HbiJ8IlgnbSozRd9IxUyilSf4BER15.1

Action Items from Last Meeting

• Identify the right video call technology to use going forward
  • Zoom seems to be fine - Chris will set up a recurrence with a stable link we can re-use.
• Open issues for:
  - QEMU CI for server
  - CI for server as swtpm: #120
  - The one commands on server: #119
  - The one command for client: #118
  - Making sure that server is infallable/ panic free: #42

Plans

MVP 1

• MIRI based undefined behavior CI: Done
• Add TPM_GetRandom Command on server side(Ahmed):
  • Implementation is complete an pending review at #136 and later at 30a2b728 as well.
  • Aleady existing implementation of TPM_GetRandom does not use marshal infrastructure and is adhoc, might require further refinement in the future.
  • Discussion: Errors and TPM Failure Mode. We should enter failure mode if the internal random number generator routines encounters a fault.
    • If someone passes >4GB of entropy to StirRandom (for example) the TPM should return a normal error and not go to failure mode.
    • If an internal routine encounters a fatal error, the TPM should go into failure mode.
• Create SWTPM(Ahmed):
  • WIP, near complete, currently figuring out some finer points in how tpm over tcp work, open to suggestions.
• Discussion: the control port and TCP based protocol
  • Not very well documented, kind of based on reading the simulator code
  • TPM2tools apparently expects it? (Chris finds this weird and also bad)

  ➜  ~ tpm2_getrandom  10  (process:362949): WARNING : 17:47:55.606:
  Failed to create connection with service:
  GDBus.Error:org.freedesktop.DBus.Error.AccessDenied: Sender is not
  authorized to send message
  ERROR:tcti:src/tss2-tcti/tctildr-dl.c:149:tcti_from_file() Could
  not initialize TCTI file: libtss2-tcti-tabrmd.so.0
  ERROR:tcti:src/tss2-tcti/tcti-device.c:455:Tss2_Tcti_Device_Init()
  Failed to open specified TCTI device file /dev/tpmrm0: Permission
  denied  ERROR:tcti:src/tss2-tcti/tctildr-dl.c:149:tcti_from_file()
  Could not initialize TCTI file: libtss2-tcti-device.so.0
  ERROR:tcti:src/tss2-tcti/tcti-device.c:455:Tss2_Tcti_Device_Init(
  Failed to open specified TCTI device file /dev/tpm0: Permission
  denied  ERROR:tcti:src/tss2-tcti/tctildr-dl.c:149:tcti_from_file()
  Could not initialize TCTI file: libtss2-tcti-device.so.0
  ERROR:tcti:src/tss2-tcti/tcti-device.c:455:Tss2_Tcti_Device_Init()
  Failed to open specified TCTI device file /dev/tcm0: No such file
  or directory  ERROR:tcti:src/tss2-tcti/tctildr-dl.c:1
  
  ➜  ~ tpm2_getrandom  -v tool="tpm2_getrandom" version="5.7"
  tctis="libtss2-tctildr" tcti-default=tcti-abrmd
  

• Add test that forbids panic symbols in the compiled binary
  • Discussion: Should we consider implementing the panic handler as a transition into Failure Mode (see above)
  • The way Caliptra handles it is that no-panic is expected and all error handling is done explicitly.
  • Which approach is more idiomatic for us (exception-like vs value-like error conditions)?
  • Likely a longer discussion to do over time. Let's reach out to the Caliptra team (AI: cfenn)
• Add TPM_GetRandom Command on client side
• Provide sample firmware implementation for the TPM

MVP 2

• Forcing functions for policy and non-policy sessions and paramter encryption
• (CreatePrimary) Make the EK for sealing blobs
• (StartAuthSession) Create sessions to auth the EK and the blob
• (PolicySecret) Satisfy the EK policy
• (Create) Seal a blob to the EK, using the EK policy, with a decrypt session
• (Load) Load the blob
• (Unseal) Unseal the blob with an encrypt session
• (FlushContext) Flush the blob and SRK

From Trent side: They will be working on client side, mainly reviews, and later client side at last for this quarter (Q4 2024).

Issues and Pull Requests for discussion

• How should tpm handle cases where internal error is triggered in commands that should not produce errors.
  • TPm has failure mode that it enter to, and we can enter that when drbg fails.
  • that requires modifcation to tpm DRBG trait and implementation.
  • in part 1.
• Is there documentation for TPM over TCP, there is two sockets command socket and control socket.
  • TPM protocol header, I just have to look in the code, no proper docs.
  • Tpm compliance test code, check for plaform capabilities.
    For Ahmed: Figure out what that is:

// TODO_RENAME_INC_FOLDER:platform_interface refers to the     TPM_CoreLib platform interface
#include <platform_interface/tpm_to_platform_interface.h>
#include <platform_interface/platform_to_tpm_interface.h>

• TODO: to be filled before, during, or after the meeting

Any other business

• We need calendar Item for the meeting.
  • Perhaps something like a Github action: https://github.com/gitevents/ics
• Google is becoming interested in the TPM client again, so probably worth me (trentreed) when I have time working more on that than server stuff. (Note that currently my time is still scheduled for non-tpmrs stuff, so it's not a priority yet).
• TODO: to be filled before, during, or after the meeting

Action Items and To-Do List

• We need mailing list.
• We need calendar Item for the meeting.
• Chris: Reach out to Caliptra team to follow up on panic/failure mode discussion
• check if there is panics in the swtpm version of our server. (Ahmed)
• TODO: to be filled before, during, or after the meeting

Next Meeting

• Date: Monday December 9
• Time: 5pm CET / 8 AM PT
• Meeting Link: TODO

Other notes (From Zoom chat)

Brad:

// TODO_RENAME_INC_FOLDER:platform_interface refers to the TPM_CoreLib platform interface

#include <platform_interface/tpm_to_platform_interface.h>

#include <platform_interface/platform_to_tpm_interface.h>

Also, I think we missed inviting Ankur & Christian to this.

probably my fault

where is the mailing list?

Chris:

https://github.com/orgs/tpm-rs/discussions/16#discussioncomment-10712807

Brad:

action: meeting link in GitHub & calendar invites

Imported from https://hackmd.io/@oddcoder/ryjHhaqAA