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-rw-r--r--ratelimiter.go139
1 files changed, 0 insertions, 139 deletions
diff --git a/ratelimiter.go b/ratelimiter.go
deleted file mode 100644
index 6e5f005..0000000
--- a/ratelimiter.go
+++ /dev/null
@@ -1,139 +0,0 @@
-package main
-
-/* Copyright (C) 2015-2017 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved. */
-
-/* This file contains a port of the ratelimited from the linux kernel version
- */
-
-import (
- "net"
- "sync"
- "time"
-)
-
-const (
- RatelimiterPacketsPerSecond = 20
- RatelimiterPacketsBurstable = 5
- RatelimiterGarbageCollectTime = time.Second
- RatelimiterPacketCost = 1000000000 / RatelimiterPacketsPerSecond
- RatelimiterMaxTokens = RatelimiterPacketCost * RatelimiterPacketsBurstable
-)
-
-type RatelimiterEntry struct {
- mutex sync.Mutex
- lastTime time.Time
- tokens int64
-}
-
-type Ratelimiter struct {
- mutex sync.RWMutex
- lastGarbageCollect time.Time
- tableIPv4 map[[net.IPv4len]byte]*RatelimiterEntry
- tableIPv6 map[[net.IPv6len]byte]*RatelimiterEntry
-}
-
-func (rate *Ratelimiter) Init() {
- rate.mutex.Lock()
- defer rate.mutex.Unlock()
- rate.tableIPv4 = make(map[[net.IPv4len]byte]*RatelimiterEntry)
- rate.tableIPv6 = make(map[[net.IPv6len]byte]*RatelimiterEntry)
- rate.lastGarbageCollect = time.Now()
-}
-
-func (rate *Ratelimiter) GarbageCollectEntries() {
- rate.mutex.Lock()
-
- // remove unused IPv4 entries
-
- for key, entry := range rate.tableIPv4 {
- entry.mutex.Lock()
- if time.Now().Sub(entry.lastTime) > RatelimiterGarbageCollectTime {
- delete(rate.tableIPv4, key)
- }
- entry.mutex.Unlock()
- }
-
- // remove unused IPv6 entries
-
- for key, entry := range rate.tableIPv6 {
- entry.mutex.Lock()
- if time.Now().Sub(entry.lastTime) > RatelimiterGarbageCollectTime {
- delete(rate.tableIPv6, key)
- }
- entry.mutex.Unlock()
- }
-
- rate.mutex.Unlock()
-}
-
-func (rate *Ratelimiter) RoutineGarbageCollector(stop Signal) {
- timer := time.NewTimer(time.Second)
- for {
- select {
- case <-stop.Wait():
- return
- case <-timer.C:
- rate.GarbageCollectEntries()
- timer.Reset(time.Second)
- }
- }
-}
-
-func (rate *Ratelimiter) Allow(ip net.IP) bool {
- var entry *RatelimiterEntry
- var KeyIPv4 [net.IPv4len]byte
- var KeyIPv6 [net.IPv6len]byte
-
- // lookup entry
-
- IPv4 := ip.To4()
- IPv6 := ip.To16()
-
- rate.mutex.RLock()
-
- if IPv4 != nil {
- copy(KeyIPv4[:], IPv4)
- entry = rate.tableIPv4[KeyIPv4]
- } else {
- copy(KeyIPv6[:], IPv6)
- entry = rate.tableIPv6[KeyIPv6]
- }
-
- rate.mutex.RUnlock()
-
- // make new entry if not found
-
- if entry == nil {
- rate.mutex.Lock()
- entry = new(RatelimiterEntry)
- entry.tokens = RatelimiterMaxTokens - RatelimiterPacketCost
- entry.lastTime = time.Now()
- if IPv4 != nil {
- rate.tableIPv4[KeyIPv4] = entry
- } else {
- rate.tableIPv6[KeyIPv6] = entry
- }
- rate.mutex.Unlock()
- return true
- }
-
- // add tokens to entry
-
- entry.mutex.Lock()
- now := time.Now()
- entry.tokens += now.Sub(entry.lastTime).Nanoseconds()
- entry.lastTime = now
- if entry.tokens > RatelimiterMaxTokens {
- entry.tokens = RatelimiterMaxTokens
- }
-
- // subtract cost of packet
-
- if entry.tokens > RatelimiterPacketCost {
- entry.tokens -= RatelimiterPacketCost
- entry.mutex.Unlock()
- return true
- }
- entry.mutex.Unlock()
- return false
-}