10 "github.com/anacrolix/missinggo"
11 "github.com/anacrolix/missinggo/perf"
12 "github.com/pkg/errors"
13 "golang.org/x/net/proxy"
16 type dialer interface {
17 dial(_ context.Context, addr string) (net.Conn, error)
20 type socket interface {
25 func getProxyDialer(proxyURL string) (proxy.Dialer, error) {
26 fixedURL, err := url.Parse(proxyURL)
31 return proxy.FromURL(fixedURL, proxy.Direct)
34 func listen(n network, addr, proxyURL string, f firewallCallback) (socket, error) {
37 return listenTcp(n.String(), addr, proxyURL)
39 return listenUtp(n.String(), addr, proxyURL, f)
45 func listenTcp(network, address, proxyURL string) (s socket, err error) {
46 l, err := net.Listen(network, address)
56 // If we don't need the proxy - then we should return default net.Dialer,
57 // otherwise, let's try to parse the proxyURL and return proxy.Dialer
58 if len(proxyURL) != 0 {
59 dl := disabledListener{l}
60 dialer, err := getProxyDialer(proxyURL)
64 return tcpSocket{dl, func(ctx context.Context, addr string) (conn net.Conn, err error) {
65 defer perf.ScopeTimerErr(&err)()
66 return dialer.Dial(network, addr)
69 dialer := net.Dialer{}
70 return tcpSocket{l, func(ctx context.Context, addr string) (conn net.Conn, err error) {
71 defer perf.ScopeTimerErr(&err)()
72 return dialer.DialContext(ctx, network, addr)
76 type disabledListener struct {
80 func (dl disabledListener) Accept() (net.Conn, error) {
81 return nil, fmt.Errorf("tcp listener disabled due to proxy")
84 type tcpSocket struct {
86 d func(ctx context.Context, addr string) (net.Conn, error)
89 func (me tcpSocket) dial(ctx context.Context, addr string) (net.Conn, error) {
90 return me.d(ctx, addr)
93 func listenAll(networks []network, getHost func(string) string, port int, proxyURL string, f firewallCallback) ([]socket, error) {
94 if len(networks) == 0 {
97 var nahs []networkAndHost
98 for _, n := range networks {
99 nahs = append(nahs, networkAndHost{n, getHost(n.String())})
102 ss, retry, err := listenAllRetry(nahs, port, proxyURL, f)
109 type networkAndHost struct {
114 func listenAllRetry(nahs []networkAndHost, port int, proxyURL string, f firewallCallback) (ss []socket, retry bool, err error) {
115 ss = make([]socket, 1, len(nahs))
116 portStr := strconv.FormatInt(int64(port), 10)
117 ss[0], err = listen(nahs[0].Network, net.JoinHostPort(nahs[0].Host, portStr), proxyURL, f)
119 return nil, false, errors.Wrap(err, "first listen")
122 if err != nil || retry {
123 for _, s := range ss {
129 portStr = strconv.FormatInt(int64(missinggo.AddrPort(ss[0].Addr())), 10)
130 for _, nah := range nahs[1:] {
131 s, err := listen(nah.Network, net.JoinHostPort(nah.Host, portStr), proxyURL, f)
134 missinggo.IsAddrInUse(err) && port == 0,
135 errors.Wrap(err, "subsequent listen")
142 type firewallCallback func(net.Addr) bool
144 func listenUtp(network, addr, proxyURL string, fc firewallCallback) (s socket, err error) {
145 us, err := NewUtpSocket(network, addr, fc)
150 // If we don't need the proxy - then we should return default net.Dialer,
151 // otherwise, let's try to parse the proxyURL and return proxy.Dialer
152 if len(proxyURL) != 0 {
153 ds := disabledUtpSocket{us}
154 dialer, err := getProxyDialer(proxyURL)
158 return utpSocketSocket{ds, network, dialer}, nil
161 return utpSocketSocket{us, network, nil}, nil
164 type disabledUtpSocket struct {
168 func (ds disabledUtpSocket) Accept() (net.Conn, error) {
169 return nil, fmt.Errorf("utp listener disabled due to proxy")
172 type utpSocketSocket struct {
178 func (me utpSocketSocket) dial(ctx context.Context, addr string) (conn net.Conn, err error) {
179 defer perf.ScopeTimerErr(&err)()
181 return me.d.Dial(me.network, addr)
184 return me.utpSocket.DialContext(ctx, me.network, addr)