Enum SecurityLevel 

pub enum SecurityLevel {
    Paranoid,
    Standard {
        ttl: Duration,
    },
    Performance {
        ttl: Duration,
    },
}

Controls the trade-off between security and performance when accessing TEE-protected data.

Level	Cached	Attack surface	Speed
Paranoid	Nothing	Minimal	Slow (TPM every call)
Standard	Data Key only	32-byte key in memory	Fast (AES-GCM only)
Performance	Data Key + plaintext	Full plaintext in memory	Fastest

Variants

Paranoid

Every unprotect() call hits the TEE (TPM unseal + AES decrypt). No plaintext or data key is ever cached in memory. Slowest, but smallest attack surface.

Standard

The unwrapped data key is cached in mlock’d, zeroize-on-drop memory for a configurable TTL. The plaintext itself is never cached. Each unprotect() still performs AES-GCM decryption, but avoids the expensive TPM unseal round-trip for repeated accesses.

Fields

ttl: Duration

How long to keep the unwrapped data key in memory.

Performance

Both the unwrapped data key AND the decrypted plaintext are cached in mlock’d, zeroize-on-drop memory for the TTL period. Fastest for repeated reads of the same data, but the plaintext lives in process memory until the TTL expires or the cache is flushed.

Fields

ttl: Duration

How long to keep cached data in memory.

Implementations

impl SecurityLevel

pub fn standard() -> Self

Standard level with a default TTL of 30 seconds.

pub fn performance() -> Self

Performance level with a default TTL of 10 seconds.

pub fn ttl(&self) -> Option<Duration>

Returns the TTL if caching is enabled, or None for Paranoid.

pub fn caches_plaintext(&self) -> bool

Returns true if plaintext caching is enabled (Performance level).

pub fn caches_data_key(&self) -> bool

Returns true if data key caching is enabled (Standard or Performance).

Trait Implementations

impl Clone for SecurityLevel

fn clone(&self) -> SecurityLevel

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for SecurityLevel

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

Formats the value using the given formatter.

impl Default for SecurityLevel

fn default() -> Self

Defaults to Paranoid for maximum security and backward compatibility.

impl PartialEq for SecurityLevel

fn eq(&self, other: &SecurityLevel) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for SecurityLevel

impl Eq for SecurityLevel

impl StructuralPartialEq for SecurityLevel