Struct RuntimeTcbFloor 

pub struct RuntimeTcbFloor { /* private fields */ }

A resident TCB floor originating exclusively from trusted local hardware.

Obtain once from platform initialization (reusing boot reports), or use Self::new before accepting worker events, then retain the same instance across attempts and errors. Blocking hardware jobs must hold the caller’s shared mutex for each complete method call. Never recreate the floor on retry or initialize it from a VMGS protector header. Trusted servicing may transfer it with Self::save and Self::restore. The caller must provide an authenticated, VM-bound, fresh servicing channel; the DTO is not proof of a hardware observation. Never deserialize a floor from VMGS or host-controlled metadata. This is not a persisted anti-rollback counter and does not protect an arbitrary restart from rollback. It has no Clone, Copy, or Default implementation; restore validates the typed DTO without observing hardware or bootstrapping a replacement floor.

SNP ordering is component-wise only for report versions 3, 4, and 5 within the exact same version/family/model. Milan/Genoa (family 0x19, models 0x00..=0x1f) and Turin (family 0x1a, models 0x90..=0xaf and 0xc0..=0xcf) use distinct layouts; reserved TCB bytes must remain equal. All other SNP domains require exact SVN equality. Version 2 has no trusted CPUID and is also equality-only. TDX uses a structural minimum-TCB policy: CPU SVN bytes must individually meet the floor. TEE SVN byte 1 must match, including legacy identity 0. For TD-preserving modules byte 0 is module ISVSVN and bytes 2..16 are platform components; these bytes must individually meet the floor in both layouts. This is not quote appraisal or an Intel TCB status decision, which requires authenticated TCB Info.

Implementations

impl RuntimeTcbFloor

pub fn save(&self) -> SavedRuntimeTcbFloor

Save only accepted SVN/domain metadata, never secrets or derived keys. The result is only for an authenticated, VM-bound, fresh servicing channel.

pub fn restore( state: SavedRuntimeTcbFloor, tee: &dyn TeeCall, config: &AttestationVmConfig, ) -> Result<Self, Error>

Validate state from an authenticated, VM-bound, fresh servicing channel. The caller establishes that trust: the DTO itself is not a proof, and must never come from VMGS, protector headers, or other host-controlled metadata. No report, key derivation, VMGS access, or bootstrap occurs here. Only the configured policy and TEE capabilities are inspected, not the live TCB. Unknown SNP domains retain their existing equality-only interpretation.

When replacing an existing resident floor, first call its Self::check_restored_successor while holding the shared state lock. Do not replace the resident floor if either validation step fails.

pub fn check_restored_successor(&self, restored: &Self) -> Result<(), Error>

Pure check that replacing this resident floor cannot decrease it or change its comparison domain. Equal floors are allowed. Neither instance is modified, including on failure. The caller must hold its shared state lock across this check and replacement; no hardware calls are made.

pub fn new( tee: &dyn TeeCall, config: &AttestationVmConfig, ) -> Result<Self, Error>

Initialize from a fresh trusted local report, without deriving any keys. The tee must be the trusted local hardware interface, not report bytes supplied by the root or by a persisted protector.

pub fn create_protector( &mut self, tee: &dyn TeeCall, config: &AttestationVmConfig, dek: &[u8; 32], ) -> Result<Vec<u8>, Error>

Validate and ratchet from a fresh report, then seal the active DEK using that same report’s SVN. Derivation/sealing errors cannot undo the ratchet. The caller performs candidate pre-write verification separately.

pub fn verify_protector( &mut self, tee: &dyn TeeCall, config: &AttestationVmConfig, protector: &[u8], dek: &[u8; 32], ) -> Result<bool, Error>

Validate and ratchet from a fresh report before inspecting the candidate. Return Ok(false) if its header SVN differs from the observed SVN, even if hardware could still derive a key for that older candidate. Otherwise freshly derive hardware keys and authenticate/unseal via the existing stateless verifier. Neither mismatches nor errors undo a ratchet.

This does not make the report and derivation atomic with migration; the caller still needs pre-write and post-flush verification and retry logic.

Trait Implementations

impl Debug for RuntimeTcbFloor

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.