Struct network::noise::handshake::AntiReplayTimestamps

pub struct AntiReplayTimestamps(_);

In a mutually authenticated network, a client message is accompanied with a timestamp. This is in order to prevent replay attacks, where the attacker does not know the client’s static key, but can still replay a handshake message in order to force a peer into performing a few Diffie-Hellman key exchange operations.

Thus, to prevent replay attacks a responder will always check if the timestamp is strictly increasing, effectively considering it as a stateful counter.

If the client timestamp has been seen before, or is not strictly increasing, we can abort the handshake early and avoid heavy Diffie-Hellman computations. If the client timestamp is valid, we store it.

Implementations

impl AntiReplayTimestamps

pub const TIMESTAMP_SIZE: usize = 8usize

The timestamp is sent as a payload, so that it is encrypted. Note that a millisecond value is a 16-byte value in rust, but as we use it to store a duration since UNIX_EPOCH we will never use more than 8 bytes.

pub fn now() -> [u8; 8]

obtain the current timestamp

pub fn is_replay(&self, pubkey: PublicKey, timestamp: u64) -> bool

Returns true if the timestamp has already been observed for this peer or if it’s an old timestamp

pub fn store_timestamp(&mut self, pubkey: PublicKey, timestamp: u64)

Stores the timestamp

Trait Implementations

impl Default for AntiReplayTimestamps

fn default() -> AntiReplayTimestamps

Returns the “default value” for a type.