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3870705eaf
A net.UDPListener is the datagram equivalent of a net.Conn. This patch accepts at most one connection from vsock and attempts to read and write UDP datagrams along it. Signed-off-by: David Scott <dave.scott@docker.com>
101 lines
2.0 KiB
Go
101 lines
2.0 KiB
Go
package libproxy
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import (
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//"encoding/binary"
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"errors"
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"net"
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//"strings"
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"sync"
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//"syscall"
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"github.com/Sirupsen/logrus"
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)
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type udpListener interface {
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ReadFromUDP(b []byte) (int, *net.UDPAddr, error)
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WriteToUDP(b []byte, addr *net.UDPAddr) (int, error)
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Close() error
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}
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type udpEncapsulator struct {
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conn *net.Conn
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listener net.Listener
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m *sync.Mutex
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r *sync.Mutex
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w *sync.Mutex
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}
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func (u *udpEncapsulator) getConn() (net.Conn, error) {
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u.m.Lock()
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defer u.m.Unlock()
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if u.conn != nil {
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return *u.conn, nil
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}
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conn, err := u.listener.Accept()
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if err != nil {
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logrus.Printf("Failed to accept connection: %#v", err)
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return nil, err
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}
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u.conn = &conn
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return conn, nil
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}
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func (u *udpEncapsulator) ReadFromUDP(b []byte) (int, *net.UDPAddr, error) {
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conn, err := u.getConn()
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if err != nil {
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return 0, nil, err
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}
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u.r.Lock()
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defer u.r.Unlock()
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datagram := &udpDatagram{payload: b}
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err = datagram.Unmarshal(conn)
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if err != nil {
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return 0, nil, err
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}
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return len(datagram.payload), &net.UDPAddr{IP: *datagram.IP, Port: datagram.Port, Zone: datagram.Zone}, nil
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}
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func (u *udpEncapsulator) WriteToUDP(b []byte, addr *net.UDPAddr) (int, error) {
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conn, err := u.getConn()
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if err != nil {
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return 0, err
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}
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u.w.Lock()
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defer u.w.Unlock()
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datagram := &udpDatagram{payload: b, IP: &addr.IP, Port: addr.Port, Zone: addr.Zone}
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return len(b), datagram.Marshal(conn)
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}
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func (u *udpEncapsulator) Close() error {
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if u.conn != nil {
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conn := *u.conn
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conn.Close()
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}
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u.listener.Close()
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return nil
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}
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func NewUDPListener(listener net.Listener) udpListener {
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var m sync.Mutex;
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return &udpEncapsulator{
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conn: nil,
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listener: listener,
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m: &m,
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}
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}
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type udpDatagram struct {
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payload []byte
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IP *net.IP
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Port int
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Zone string
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}
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func (u *udpDatagram) Marshal(conn net.Conn) error {
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return errors.New("Marshal unimplemented")
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}
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func (u *udpDatagram) Unmarshal(conn net.Conn) error {
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return errors.New("Unmarshal unimplemented")
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}
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