1 files changed, 129 insertions, 0 deletions
diff --git a/webircgateway/pkg/proxy/proxy.go b/webircgateway/pkg/proxy/proxy.go
new file mode 100644
index 0000000..c332f40
--- /dev/null
+++ b/webircgateway/pkg/proxy/proxy.go
@@ -0,0 +1,129 @@
+package proxy
+
+import (
+	"encoding/json"
+	"errors"
+	"io"
+	"net"
+)
+
+type KiwiProxyState int
+
+const KiwiProxyStateClosed KiwiProxyState = 0
+const KiwiProxyStateConnecting KiwiProxyState = 1
+const KiwiProxyStateHandshaking KiwiProxyState = 2
+const KiwiProxyStateConnected KiwiProxyState = 3
+
+type ConnError struct {
+	Msg  string
+	Type string
+}
+
+func (err *ConnError) Error() string {
+	return err.Msg
+}
+
+type KiwiProxyConnection struct {
+	Username       string
+	ProxyInterface string
+	DestHost       string
+	DestPort       int
+	DestTLS        bool
+	State          KiwiProxyState
+	Conn           *net.Conn
+}
+
+func MakeKiwiProxyConnection() *KiwiProxyConnection {
+	return &KiwiProxyConnection{
+		State: KiwiProxyStateClosed,
+	}
+}
+
+func (c *KiwiProxyConnection) Close() error {
+	if c.State == KiwiProxyStateClosed {
+		return errors.New("Connection already closed")
+	}
+
+	return (*c.Conn).Close()
+}
+
+func (c *KiwiProxyConnection) Dial(proxyServerAddr string) error {
+	if c.State != KiwiProxyStateClosed {
+		return errors.New("Connection in closed state")
+	}
+
+	c.State = KiwiProxyStateConnecting
+
+	conn, err := net.Dial("tcp", proxyServerAddr)
+	if err != nil {
+		return err
+	}
+
+	c.Conn = &conn
+	c.State = KiwiProxyStateHandshaking
+
+	meta, _ := json.Marshal(map[string]interface{}{
+		"username":  c.Username,
+		"interface": c.ProxyInterface,
+		"host":      c.DestHost,
+		"port":      c.DestPort,
+		"ssl":       c.DestTLS,
+	})
+
+	(*c.Conn).Write(append(meta, byte('\n')))
+
+	buf := make([]byte, 1024)
+	bufLen, readErr := (*c.Conn).Read(buf)
+	if readErr != nil {
+		(*c.Conn).Close()
+		c.State = KiwiProxyStateClosed
+		return readErr
+	}
+
+	response := string(buf)
+	if bufLen > 0 && response[0] == '1' {
+		c.State = KiwiProxyStateConnected
+	} else {
+		(*c.Conn).Close()
+		c.State = KiwiProxyStateClosed
+
+		if bufLen == 0 {
+			return errors.New("The proxy could not connect to the destination")
+		}
+
+		switch response[0] {
+		case '0':
+			return errors.New("The proxy could not connect to the destination")
+		case '2':
+			return &ConnError{Msg: "Connection reset", Type: "conn_reset"}
+		case '3':
+			return &ConnError{Msg: "Connection refused", Type: "conn_refused"}
+		case '4':
+			return &ConnError{Msg: "Host not found", Type: "not_found"}
+		case '5':
+			return &ConnError{Msg: "Connection timed out", Type: "conn_timeout"}
+		}
+	}
+
+	return nil
+}
+
+func (c *KiwiProxyConnection) Read(b []byte) (n int, err error) {
+	if c.State == KiwiProxyStateConnecting || c.State == KiwiProxyStateHandshaking {
+		return 0, nil
+	} else if c.State == KiwiProxyStateClosed {
+		return 0, io.EOF
+	} else {
+		return (*c.Conn).Read(b)
+	}
+}
+
+func (c *KiwiProxyConnection) Write(b []byte) (n int, err error) {
+	if c.State == KiwiProxyStateConnecting || c.State == KiwiProxyStateHandshaking {
+		return 0, nil
+	} else if c.State == KiwiProxyStateClosed {
+		return 0, io.EOF
+	} else {
+		return (*c.Conn).Write(b)
+	}
+}