diff options
Diffstat (limited to 'plugin/forward/persistent.go')
| -rw-r--r-- | plugin/forward/persistent.go | 43 |
1 files changed, 31 insertions, 12 deletions
diff --git a/plugin/forward/persistent.go b/plugin/forward/persistent.go index 6a7c4464e..7bf083b49 100644 --- a/plugin/forward/persistent.go +++ b/plugin/forward/persistent.go @@ -1,6 +1,7 @@ package forward import ( + "crypto/tls" "net" "time" @@ -21,8 +22,10 @@ type connErr struct { // transport hold the persistent cache. type transport struct { - conns map[string][]*persistConn // Buckets for udp, tcp and tcp-tls. - host *host + conns map[string][]*persistConn // Buckets for udp, tcp and tcp-tls. + expire time.Duration // After this duration a connection is expired. + addr string + tlsConfig *tls.Config dial chan string yield chan connErr @@ -35,10 +38,11 @@ type transport struct { stop chan bool } -func newTransport(h *host) *transport { +func newTransport(addr string, tlsConfig *tls.Config) *transport { t := &transport{ conns: make(map[string][]*persistConn), - host: h, + expire: defaultExpire, + addr: addr, dial: make(chan string), yield: make(chan connErr), ret: make(chan connErr), @@ -51,7 +55,7 @@ func newTransport(h *host) *transport { } // len returns the number of connection, used for metrics. Can only be safely -// used inside connManager() because of races. +// used inside connManager() because of data races. func (t *transport) len() int { l := 0 for _, conns := range t.conns { @@ -79,7 +83,7 @@ Wait: i := 0 for i = 0; i < len(t.conns[proto]); i++ { pc := t.conns[proto][i] - if time.Since(pc.used) < t.host.expire { + if time.Since(pc.used) < t.expire { // Found one, remove from pool and return this conn. t.conns[proto] = t.conns[proto][i+1:] t.ret <- connErr{pc.c, nil} @@ -91,22 +95,22 @@ Wait: // Not conns were found. Connect to the upstream to create one. t.conns[proto] = t.conns[proto][i:] - SocketGauge.WithLabelValues(t.host.addr).Set(float64(t.len())) + SocketGauge.WithLabelValues(t.addr).Set(float64(t.len())) go func() { if proto != "tcp-tls" { - c, err := dns.DialTimeout(proto, t.host.addr, dialTimeout) + c, err := dns.DialTimeout(proto, t.addr, dialTimeout) t.ret <- connErr{c, err} return } - c, err := dns.DialTimeoutWithTLS("tcp", t.host.addr, t.host.tlsConfig, dialTimeout) + c, err := dns.DialTimeoutWithTLS("tcp", t.addr, t.tlsConfig, dialTimeout) t.ret <- connErr{c, err} }() case conn := <-t.yield: - SocketGauge.WithLabelValues(t.host.addr).Set(float64(t.len() + 1)) + SocketGauge.WithLabelValues(t.addr).Set(float64(t.len() + 1)) // no proto here, infer from config and conn if _, ok := conn.c.Conn.(*net.UDPConn); ok { @@ -114,7 +118,7 @@ Wait: continue Wait } - if t.host.tlsConfig == nil { + if t.tlsConfig == nil { t.conns["tcp"] = append(t.conns["tcp"], &persistConn{conn.c, time.Now()}) continue Wait } @@ -134,15 +138,30 @@ Wait: } } +// Dial dials the address configured in transport, potentially reusing a connection or creating a new one. func (t *transport) Dial(proto string) (*dns.Conn, error) { + // If tls has been configured; use it. + if t.tlsConfig != nil { + proto = "tcp-tls" + } + t.dial <- proto c := <-t.ret return c.c, c.err } +// Yield return the connection to transport for reuse. func (t *transport) Yield(c *dns.Conn) { t.yield <- connErr{c, nil} } -// Stop stops the transports. +// Stop stops the transport's connection manager. func (t *transport) Stop() { t.stop <- true } + +// SetExpire sets the connection expire time in transport. +func (t *transport) SetExpire(expire time.Duration) { t.expire = expire } + +// SetTLSConfig sets the TLS config in transport. +func (t *transport) SetTLSConfig(cfg *tls.Config) { t.tlsConfig = cfg } + +const defaultExpire = 10 * time.Second |