mirror of
https://github.com/jmcorgan/fips.git
synced 2026-08-11 17:17:54 +00:00
Johnathan Corgan
9697026c81
Hoist the two line-for-line-identical per-destination minimum-interval limiters (discovery forward, routing error) into a shared PerAddrRateLimiter, and fold the duplicated exponential-backoff math (discovery originator, FMP retry) into a shared backoff_ms helper, both in a new proto/rate_limit module. The subsystem limiters become thin delegating newtypes so should_forward/should_send and the backoff call conventions are preserved. Behavior is byte-identical.
61 lines
2.0 KiB
Rust
61 lines
2.0 KiB
Rust
//! Shared `proto` rate-limiting / backoff primitives: a per-address
|
|
//! minimum-interval limiter and an exponential backoff helper, hoisted out of
|
|
//! the subsystem `limits.rs` files.
|
|
|
|
use crate::NodeAddr;
|
|
use alloc::collections::BTreeMap;
|
|
|
|
/// Per-address minimum-interval rate limiter. Tracks the last event time per
|
|
/// address and enforces a minimum interval, evicting entries older than a max age.
|
|
pub(crate) struct PerAddrRateLimiter {
|
|
last: BTreeMap<NodeAddr, u64>,
|
|
min_interval_ms: u64,
|
|
max_age_ms: u64,
|
|
}
|
|
|
|
impl PerAddrRateLimiter {
|
|
pub(crate) fn new(min_interval_ms: u64, max_age_ms: u64) -> Self {
|
|
Self {
|
|
last: BTreeMap::new(),
|
|
min_interval_ms,
|
|
max_age_ms,
|
|
}
|
|
}
|
|
|
|
/// Returns true (and records `now_ms`) if enough time has elapsed since the
|
|
/// last event for `addr`, or this is the first; false if within the interval.
|
|
pub(crate) fn check_and_record(&mut self, addr: &NodeAddr, now_ms: u64) -> bool {
|
|
if let Some(&last) = self.last.get(addr)
|
|
&& now_ms.saturating_sub(last) < self.min_interval_ms
|
|
{
|
|
return false;
|
|
}
|
|
self.last.insert(*addr, now_ms);
|
|
self.cleanup(now_ms);
|
|
true
|
|
}
|
|
|
|
pub(crate) fn cleanup(&mut self, now_ms: u64) {
|
|
self.last
|
|
.retain(|_, &mut last| now_ms.saturating_sub(last) < self.max_age_ms);
|
|
}
|
|
|
|
#[cfg(test)]
|
|
pub(crate) fn set_interval_ms(&mut self, interval_ms: u64) {
|
|
self.min_interval_ms = interval_ms;
|
|
}
|
|
|
|
#[cfg(test)]
|
|
pub(crate) fn len(&self) -> usize {
|
|
self.last.len()
|
|
}
|
|
}
|
|
|
|
/// Exponential (base-2) backoff: `base_ms * 2^exponent`, saturating, capped at
|
|
/// `cap_ms`. Shared by the discovery originator backoff (exponent = failures-1)
|
|
/// and the FMP retry scheduler (exponent = retry_count).
|
|
pub(crate) fn backoff_ms(exponent: u32, base_ms: u64, cap_ms: u64) -> u64 {
|
|
let multiplier = 1u64.checked_shl(exponent).unwrap_or(u64::MAX);
|
|
base_ms.saturating_mul(multiplier).min(cap_ms)
|
|
}
|