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# System prepended metadata

title: 'Attestation: Details of SGX DCAP + Provisioning and attestation protocols in Intel TDX'

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# Attestation: Details of SGX DCAP + Provisioning and attestation protocols in Intel TDX
Moderator: Felix

# Usama Sardar, Scott Raynor, Ravi Sahita


Roll Call:
- Ravi Sahita
- Scott Raynor
- Muhammad Usama Sardar 
- Felix
- Ned Smith
- Vinnie Scarlata

## Readings 
- [DCAP](https://www.researchgate.net/publication/343826554_Formal_Foundations_for_Intel_SGX_Data_Center_Attestation_Primitives) 
- [TDX](https://www.researchgate.net/publication/351699567_Demystifying_Attestation_in_Intel_Trust_Domain_Extensions_via_Formal_Verification)

## DCAP presentation

- PCCS caches attestation colletarals from Intel
- Can be used offline

## TDX presentation

- Four additional registers that are similar to PCRs in TPMs (RTMRs)
- a virtual TPM could be built on this
- The Intel TDX Module is the core TCB element for TDs
    - "A privileged library in the VMM" - protected in memory via SEAMRR (and uses own confidential key) and measured by CPU via an Intel ACM
- Intel TDX Module issues attestation statements to TD
- There is a new SEAM CPU mode (which introduces ISA - SEAMCALL, SEAMRET, TDCALL (get report is one of the ops), SEAMOPS)
- The SEAM is sort of a software version of AMD SEV's SP (on-die Arm chip)
- in short term the attestation infrastructure stays based on SGX, however in long term Intel's looking on ways of scaling TDX attestations

Discussion!
- DCAP is a set of building blocks that can be used to implement end-to-end solutions
- Intel Security Library has a production quality end-to-end solution
- [Link to Intel Security Library](https://01.org/intel-secl)
- Any FLC (flexible launch control) system allows for custom quoting enclaves
- Azure is still using the default Intel quoting enclaves


Follow ups:
- *what cool stuff did you learn?*
- *what should the community do next?*
