Struct ReplayWindow 

pub struct ReplayWindow {
    pub window_size: usize,
    pub seen_nonces: VecDeque<u64>,
    pub last_sequence: u64,
}

Sliding window of recently observed nonces used to detect replay attacks.

Operates as a bounded FIFO: when the window is full, the oldest nonce is evicted to make room for the newcomer.

Fields

window_size: usize

Maximum number of nonces retained at once.

seen_nonces: VecDeque<u64>

Ordered queue of recently seen nonces (oldest first).

last_sequence: u64

Highest sequence_num seen so far (used for sequential nonce policy).

Implementations

impl ReplayWindow

pub fn new(window_size: usize) -> Self

Create a new ReplayWindow with the given capacity.

pub fn contains(&self, nonce: u64) -> bool

Return true if nonce was already seen within the window.

pub fn record(&mut self, nonce: u64)

Record nonce; evict the oldest entry if the window is at capacity.

When window_size == 0 the nonce is discarded — no replay detection is performed.

Trait Implementations

impl Clone for ReplayWindow

fn clone(&self) -> ReplayWindow

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ReplayWindow

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

Formats the value using the given formatter.