diff options
author | Mathias Hall-Andersen <mathias@hall-andersen.dk> | 2018-02-12 22:29:11 +0100 |
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committer | Mathias Hall-Andersen <mathias@hall-andersen.dk> | 2018-02-12 22:29:11 +0100 |
commit | ea4ea6f9334b8979bec6a881d7f94d7fa94e9b9c (patch) | |
tree | e939f1c2e4c09d871918a08e9646572e318e6cf1 /ratelimiter.go | |
parent | bffe99aeadae09abd02f2bd3184925af6b680535 (diff) |
Revert "Don't use modules"
This reverts commit bffe99aeadae09abd02f2bd3184925af6b680535.
Diffstat (limited to 'ratelimiter.go')
-rw-r--r-- | ratelimiter.go | 149 |
1 files changed, 0 insertions, 149 deletions
diff --git a/ratelimiter.go b/ratelimiter.go deleted file mode 100644 index 168a743..0000000 --- a/ratelimiter.go +++ /dev/null @@ -1,149 +0,0 @@ -package main - -/* Copyright (C) 2015-2017 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved. */ - -/* This file contains a port of the rate-limiter from the linux kernel version */ - -import ( - "net" - "sync" - "time" -) - -const ( - packetsPerSecond = 20 - packetsBurstable = 5 - garbageCollectTime = time.Second - packetCost = 1000000000 / packetsPerSecond - maxTokens = packetCost * packetsBurstable -) - -type RatelimiterEntry struct { - mutex sync.Mutex - lastTime time.Time - tokens int64 -} - -type Ratelimiter struct { - mutex sync.RWMutex - stop chan struct{} - tableIPv4 map[[net.IPv4len]byte]*RatelimiterEntry - tableIPv6 map[[net.IPv6len]byte]*RatelimiterEntry -} - -func (rate *Ratelimiter) Close() { - rate.mutex.Lock() - defer rate.mutex.Unlock() - - if rate.stop != nil { - close(rate.stop) - } -} - -func (rate *Ratelimiter) Init() { - rate.mutex.Lock() - defer rate.mutex.Unlock() - - // stop any ongoing garbage collection routine - - if rate.stop != nil { - close(rate.stop) - } - - rate.stop = make(chan struct{}) - rate.tableIPv4 = make(map[[net.IPv4len]byte]*RatelimiterEntry) - rate.tableIPv6 = make(map[[net.IPv6len]byte]*RatelimiterEntry) - - // start garbage collection routine - - go func() { - timer := time.NewTimer(time.Second) - for { - select { - case <-rate.stop: - return - case <-timer.C: - func() { - rate.mutex.Lock() - defer rate.mutex.Unlock() - - for key, entry := range rate.tableIPv4 { - entry.mutex.Lock() - if time.Now().Sub(entry.lastTime) > garbageCollectTime { - delete(rate.tableIPv4, key) - } - entry.mutex.Unlock() - } - - for key, entry := range rate.tableIPv6 { - entry.mutex.Lock() - if time.Now().Sub(entry.lastTime) > garbageCollectTime { - delete(rate.tableIPv6, key) - } - entry.mutex.Unlock() - } - }() - 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 = maxTokens - packetCost - 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 > maxTokens { - entry.tokens = maxTokens - } - - // subtract cost of packet - - if entry.tokens > packetCost { - entry.tokens -= packetCost - entry.mutex.Unlock() - return true - } - entry.mutex.Unlock() - return false -} |