Struct tlspuffin::tls::rustls::ticketer::TicketSwitcher

struct TicketSwitcher {
    generator: fn() -> Result<Box<dyn ProducesTickets>, GetRandomFailed>,
    lifetime: u32,
    state: Mutex<TicketSwitcherState>,
}

A ticketer that has a ‘current’ sub-ticketer and a single ‘previous’ ticketer. It creates a new ticketer every so often, demoting the current ticketer.

Fields

generator: fn() -> Result<Box<dyn ProducesTickets>, GetRandomFailed>

lifetime: u32

state: Mutex<TicketSwitcherState>

Implementations

impl TicketSwitcher

fn new( lifetime: u32, generator: fn() -> Result<Box<dyn ProducesTickets>, GetRandomFailed>, ) -> Result<Self, Error>

lifetime is in seconds, and is how long the current ticketer is used to generate new tickets. Tickets are accepted for no longer than twice this duration. generator produces a new ProducesTickets implementation.

fn maybe_roll( &self, now: TimeBase, ) -> Option<MutexGuard<'_, TicketSwitcherState>>

If it’s time, demote the current ticketer to previous (so it does no new encryptions but can do decryption) and use next for a new current ticketer.

Calling this regularly will ensure timely key erasure. Otherwise, key erasure will be delayed until the next encrypt/decrypt call.

For efficiency, this is also responsible for locking the state mutex and returning the mutexguard.

Trait Implementations

impl ProducesTickets for TicketSwitcher

fn lifetime(&self) -> u32

Returns the lifetime in seconds of tickets produced now. The lifetime is provided as a hint to clients that the ticket will not be useful after the given time.

fn enabled(&self) -> bool

Returns true if this implementation will encrypt/decrypt tickets. Should return false if this is a dummy implementation: the server will not send the SessionTicket extension and will not call the other functions.

fn encrypt(&self, message: &[u8]) -> Option<Vec<u8>>

Encrypt and authenticate plain, returning the resulting ticket. Return None if plain cannot be encrypted for some reason: an empty ticket will be sent and the connection will continue.

fn decrypt(&self, ciphertext: &[u8]) -> Option<Vec<u8>>

Decrypt cipher, validating its authenticity protection and recovering the plaintext. cipher is fully attacker controlled, so this decryption must be side-channel free, panic-proof, and otherwise bullet-proof. If the decryption fails, return None.