+package client
+
+import (
+ "fmt"
+ "net"
+ "os"
+ "errors"
+ "time"
+
+ "github.com/agl/ed25519"
+ "cypherpunks.ru/govpn"
+)
+
+type Protocol uint8
+
+const (
+ ProtocolUDP Protocol = iota
+ ProtocolTCP
+)
+
+type Configuration struct {
+ PrivateKey *[ed25519.PrivateKeySize]byte
+ Peer *govpn.PeerConf
+ Protocol Protocol
+ InterfaceName string
+ ProxyAddress string
+ ProxyAuthentication string
+ RemoteAddress string
+ UpPath, DownPath string
+ StatsAddress string
+ NoReconnect bool
+ MTU int
+}
+
+func (c *Configuration) Validate() error {
+ if c.MTU > govpn.MTUMax {
+ return fmt.Errorf("Invalid MTU %d, maximum allowable is %d",c.MTU, govpn.MTUMax)
+ }
+ if len(c.RemoteAddress) == 0 {
+ return errors.New("Missing RemoteAddress")
+ }
+ if len(c.InterfaceName) == 0 {
+ return errors.New("Missing InterfaceName")
+ }
+ return nil
+}
+
+func (c *Configuration) isProxy() bool {
+ return len(c.ProxyAddress) > 0
+}
+
+type Client struct {
+ idsCache *govpn.MACCache
+ tap *govpn.TAP
+ knownPeers govpn.KnownPeers
+ statsPort net.Listener
+ timeouted chan struct{}
+ rehandshaking chan struct{}
+ termination chan struct{}
+ firstUpCall bool
+ termSignal chan os.Signal
+ config Configuration
+
+ // Error receive any error of all routines
+ Error chan error
+}
+
+func (c *Client) MainCycle() {
+ var err error
+ c.tap, err = govpn.TAPListen(c.config.InterfaceName, c.config.MTU)
+ if err != nil {
+ c.Error <- fmt.Errorf("Can not listen on TUN/TAP interface: %s", err.Error())
+ return
+ }
+
+ if len(c.config.StatsAddress) > 0 {
+ c.statsPort, err = net.Listen("tcp", c.config.StatsAddress)
+ if err != nil {
+ c.Error <- fmt.Errorf("Can't listen on stats port: %s", err.Error())
+ return
+ }
+ c.knownPeers = govpn.KnownPeers(make(map[string]**govpn.Peer))
+ go govpn.StatsProcessor(c.statsPort, &c.knownPeers)
+ }
+
+ MainCycle:
+ for {
+ c.timeouted = make(chan struct{})
+ c.rehandshaking = make(chan struct{})
+ c.termination = make(chan struct{})
+ switch c.config.Protocol {
+ case ProtocolUDP:
+ go c.startUDP()
+ case ProtocolTCP:
+ if c.config.isProxy() {
+ go c.proxyTCP()
+ } else {
+ go c.startTCP()
+ }
+ }
+ select {
+ case <-c.termSignal:
+ govpn.BothPrintf(`[finish remote="%s"]`, c.config.RemoteAddress)
+ c.termination <- struct{}{}
+ // send a non-error to let know everything went fine
+ c.Error <- nil
+ break MainCycle
+ case <-c.timeouted:
+ if c.config.NoReconnect {
+ break MainCycle
+ }
+ govpn.BothPrintf(`[sleep seconds="%d"]`, c.config.Peer.Timeout)
+ time.Sleep(c.config.Peer.Timeout)
+ case <-c.rehandshaking:
+ }
+ close(c.timeouted)
+ close(c.rehandshaking)
+ close(c.termination)
+ }
+ if _, err = govpn.ScriptCall(c.config.DownPath, c.config.InterfaceName, c.config.RemoteAddress); err != nil {
+ c.Error <- err
+ }
+}
+
+func NewClient(conf Configuration, verifier *govpn.Verifier, termSignal chan os.Signal) *Client {
+ client := &Client{
+ idsCache: govpn.NewMACCache(),
+ firstUpCall: true,
+ config: conf,
+ termSignal: termSignal,
+ Error: make(chan error, 1),
+ }
+ confs := map[govpn.PeerId]*govpn.PeerConf{*verifier.Id: conf.Peer}
+ client.idsCache.Update(&confs)
+ return client
+}