1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
|
package quicwrapper
import (
"context"
"crypto/tls"
"net"
"sync"
"sync/atomic"
"github.com/apex/log"
"github.com/getlantern/ops"
quic "github.com/lucas-clemente/quic-go"
)
// ListenAddr creates a QUIC server listening on a given address.
// The net.Conn instances returned by the net.Listener may be multiplexed connections.
func ListenAddr(addr string, tlsConf *tls.Config, config *Config) (net.Listener, error) {
tlsConf = defaultNextProtos(tlsConf, DefaultServerProtos)
ql, err := quic.ListenAddr(addr, tlsConf, config)
if err != nil {
return nil, err
}
return listen(ql, tlsConf, config)
}
// Listen creates a QUIC server listening on a given net.PacketConn
// The net.Conn instances returned by the net.Listener may be multiplexed connections.
// The caller is responsible for closing the net.PacketConn after the listener has been
// closed.
func Listen(pconn net.PacketConn, tlsConf *tls.Config, config *Config) (net.Listener, error) {
tlsConf = defaultNextProtos(tlsConf, DefaultServerProtos)
ql, err := quic.Listen(pconn, tlsConf, config)
if err != nil {
return nil, err
}
return listen(ql, tlsConf, config)
}
func listen(ql quic.Listener, tlsConf *tls.Config, config *Config) (net.Listener, error) {
l := &listener{
quicListener: ql,
config: config,
connections: make(chan net.Conn, 1000),
acceptError: make(chan error, 1),
closedSignal: make(chan struct{}),
}
// XXX wat is this?
ops.Go(l.listen)
//ops.Go(l.logStats)
return l, nil
}
var _ net.Listener = &listener{}
// wraps quic.Listener to create a net.Listener
type listener struct {
numConnections int64
numVirtualConnections int64
quicListener quic.Listener
config *Config
connections chan net.Conn
acceptError chan error
closedSignal chan struct{}
closeErr error
closeOnce sync.Once
}
// implements net.Listener.Accept
func (l *listener) Accept() (net.Conn, error) {
select {
case conn, ok := <-l.connections:
if !ok {
return nil, ErrListenerClosed
}
return conn, nil
case err, ok := <-l.acceptError:
if !ok {
return nil, ErrListenerClosed
}
return nil, err
case <-l.closedSignal:
return nil, ErrListenerClosed
}
}
// implements net.Listener.Close
// Shut down the QUIC listener.
// this implicitly sends CONNECTION_CLOSE frames to peers
// note: it is still the responsibility of the caller
// to call Close() on any Conn returned from Accept()
func (l *listener) Close() error {
l.closeOnce.Do(func() {
close(l.closedSignal)
l.closeErr = l.quicListener.Close()
})
return l.closeErr
}
func (l *listener) isClosed() bool {
select {
case <-l.closedSignal:
return true
default:
return false
}
}
// implements net.Listener.Addr
func (l *listener) Addr() net.Addr {
return l.quicListener.Addr()
}
func (l *listener) listen() {
group := &sync.WaitGroup{}
defer func() {
l.Close()
close(l.acceptError)
// wait for writers to exit, drain connections
group.Wait()
close(l.connections)
for c := range l.connections {
c.Close()
}
log.Debugf("Listener finished with Connections: %d Virtual: %d", atomic.LoadInt64(&l.numConnections), atomic.LoadInt64(&l.numVirtualConnections))
}()
for {
session, err := l.quicListener.Accept(context.Background())
if err != nil {
if !l.isClosed() {
l.acceptError <- err
}
return
}
if l.isClosed() {
session.CloseWithError(0, "")
return
} else {
atomic.AddInt64(&l.numConnections, 1)
group.Add(1)
ops.Go(func() {
l.handleSession(session)
atomic.AddInt64(&l.numConnections, -1)
group.Done()
})
}
}
}
func (l *listener) handleSession(session quic.Connection) {
// keep a smoothed average of the bandwidth estimate
// for the session
// bw := NewEMABandwidthSampler(session)
// bw.Start()
// track active session connections
active := make(map[quic.StreamID]Conn)
var mx sync.Mutex
defer func() {
// bw.Stop()
session.CloseWithError(0, "")
// snapshot any non-closed connections, then nil out active list
// conns being closed will 'remove' themselves from the nil
// list, not the snapshot.
var snapshot map[quic.StreamID]Conn
mx.Lock()
snapshot = active
active = nil
mx.Unlock()
// immediately close any connections that are still active
for _, conn := range snapshot {
conn.Close()
}
}()
for {
stream, err := session.AcceptStream(context.Background())
if err != nil {
if isPeerGoingAway(err) {
// log.Tracef("Accepting stream: Peer going away (%v)", err)
return
} else {
// log.Errorf("Accepting stream: %v", err)
return
}
} else {
atomic.AddInt64(&l.numVirtualConnections, 1)
conn := newConn(stream, session, func(id quic.StreamID) {
atomic.AddInt64(&l.numVirtualConnections, -1)
// remove conn from active list
mx.Lock()
delete(active, id)
mx.Unlock()
})
l.connections <- conn
}
}
}
|
