commit 824d87ebdd24ffb90f5f500383d9c7926561b3cc Author: David Fifield david@bamsoftware.com Date: Mon Nov 26 23:38:39 2012 -0800

Better factoring of SOCKS requests. --- websocket-transport/socks.go | 19 ++++++++++++++ websocket-transport/websocket-client.go | 42 +++++++++++++----------------- 2 files changed, 37 insertions(+), 24 deletions(-)

diff --git a/websocket-transport/socks.go b/websocket-transport/socks.go index e8ef51f..89d83ad 100644 --- a/websocket-transport/socks.go +++ b/websocket-transport/socks.go @@ -18,6 +18,25 @@ const ( socksRequestFailed = 0x5b )

+// Read a SOCKS4a connect request, and call the given connect callback with the +// requested destination string. If the callback returns an error, sends a SOCKS +// request failed message. Otherwise, sends a SOCKS request granted message for +// the destination address returned by the callback. +func AwaitSocks4aConnect(conn *net.TCPConn, connect func(string) (*net.TCPAddr, error)) error { + dest, err := ReadSocks4aConnect(conn) + if err != nil { + SendSocks4aResponseFailed(conn) + return err + } + destAddr, err := connect(dest) + if err != nil { + SendSocks4aResponseFailed(conn) + return err + } + SendSocks4aResponseGranted(conn, destAddr) + return nil +} + // Read a SOCKS4a connect request. Returns a "host:port" string. func ReadSocks4aConnect(s io.Reader) (string, error) { r := bufio.NewReader(s) diff --git a/websocket-transport/websocket-client.go b/websocket-transport/websocket-client.go index 1259a50..129e90a 100644 --- a/websocket-transport/websocket-client.go +++ b/websocket-transport/websocket-client.go @@ -101,36 +101,30 @@ func handleConnection(conn *net.TCPConn) error { handlerChan <- -1 }()

- conn.SetDeadline(time.Now().Add(socksTimeout * time.Second)) - dest, err := ReadSocks4aConnect(conn) - if err != nil { - SendSocks4aResponseFailed(conn) - return err - } - // Disable deadline. - conn.SetDeadline(time.Time{}) - logDebug("SOCKS request for %s", dest) - - // We need the parsed IP and port for the SOCKS reply. - destAddr, err := net.ResolveTCPAddr("tcp", dest) - if err != nil { - SendSocks4aResponseFailed(conn) - return err - } + var ws *websocket.Conn

- wsUrl := url.URL{Scheme: "ws", Host: dest} - ws, err := websocket.Dial(wsUrl.String(), "", wsUrl.String()) + conn.SetDeadline(time.Now().Add(socksTimeout * time.Second)) + err := AwaitSocks4aConnect(conn, func(dest string) (*net.TCPAddr, error) { + // Disable deadline. + conn.SetDeadline(time.Time{}) + logDebug("SOCKS request for %s", dest) + destAddr, err := net.ResolveTCPAddr("tcp", dest) + if err != nil { + return nil, err + } + wsUrl := url.URL{Scheme: "ws", Host: dest} + ws, err = websocket.Dial(wsUrl.String(), "", wsUrl.String()) + if err != nil { + return nil, err + } + logDebug("WebSocket connection to %s", ws.Config().Location.String()) + return destAddr, nil + }) if err != nil { - SendSocks4aResponseFailed(conn) return err } defer ws.Close() - logDebug("WebSocket connection to %s", ws.Config().Location.String()) - - SendSocks4aResponseGranted(conn, destAddr) - proxy(conn, ws) - return nil }