func NewTunnelledSSHClient(user, tunaddr, tgtaddr string, checker *HostKeyChecker, agentForwarding bool, timeout time.Duration) (*SSHForwardingClient, error) {
clientConfig, err := sshClientConfig(user, checker)
if err != nil {
return nil, err
}
tunaddr = maybeAddDefaultPort(tunaddr)
tgtaddr = maybeAddDefaultPort(tgtaddr)
var tunnelClient *gossh.Client
dialFunc := func(echan chan error) {
var err error
tunnelClient, err = gossh.Dial("tcp", tunaddr, clientConfig)
echan <- err
}
err = timeoutSSHDial(dialFunc, timeout)
if err != nil {
return nil, err
}
var targetConn net.Conn
dialFunc = func(echan chan error) {
tgtTCPAddr, err := net.ResolveTCPAddr("tcp", tgtaddr)
if err != nil {
echan <- err
return
}
targetConn, err = tunnelClient.DialTCP("tcp", nil, tgtTCPAddr)
echan <- err
}
err = timeoutSSHDial(dialFunc, timeout)
if err != nil {
return nil, err
}
c, chans, reqs, err := gossh.NewClientConn(targetConn, tgtaddr, clientConfig)
if err != nil {
return nil, err
}
return newSSHForwardingClient(gossh.NewClient(c, chans, reqs), agentForwarding)
}
// ForwardToAgent routes authentication requests to the given keyring.
func ForwardToAgent(client *ssh.Client, keyring Agent) error {
channels := client.HandleChannelOpen(channelType)
if channels == nil {
return errors.New("agent: already have handler for " + channelType)
}
go func() {
for ch := range channels {
channel, reqs, err := ch.Accept()
if err != nil {
continue
}
go ssh.DiscardRequests(reqs)
go func() {
ServeAgent(keyring, channel)
channel.Close()
}()
}
}()
return nil
}
// ForwardToRemote routes authentication requests to the ssh-agent
// process serving on the given unix socket.
func ForwardToRemote(client *ssh.Client, addr string) error {
channels := client.HandleChannelOpen(channelType)
if channels == nil {
return errors.New("agent: already have handler for " + channelType)
}
conn, err := net.Dial("unix", addr)
if err != nil {
return err
}
conn.Close()
go func() {
for ch := range channels {
channel, reqs, err := ch.Accept()
if err != nil {
continue
}
go ssh.DiscardRequests(reqs)
go forwardUnixSocket(channel, addr)
}
}()
return nil
}