func proxyCommand(host *config.Host, command string) error {
command = host.ExpandString(command)
args, err := shlex.Split(command)
Logger.Debugf("ProxyCommand: %s", command)
if err != nil {
return err
}
spawn := exec.Command(args[0], args[1:]...)
spawn.Stdout = os.Stdout
spawn.Stdin = os.Stdin
spawn.Stderr = os.Stderr
return spawn.Run()
}
func proxyCommand(host *config.Host, command string, dryRun bool) error {
command = host.ExpandString(command)
Logger.Debugf("ProxyCommand: %s", command)
args, err := shlex.Split(command)
if err != nil {
return err
}
if dryRun {
return fmt.Errorf("dry-run: Execute %s", args)
}
spawn := exec.Command(args[0], args[1:]...)
spawn.Stdout = os.Stdout
spawn.Stdin = os.Stdin
spawn.Stderr = os.Stderr
return spawn.Run()
}
func proxy(host *config.Host, conf *config.Config) error {
if len(host.Gateways) > 0 {
Logger.Debugf("Trying gateways: %s", host.Gateways)
for _, gateway := range host.Gateways {
if gateway == "direct" {
err := proxyDirect(host)
if err != nil {
Logger.Errorf("Failed to use 'direct' connection")
}
} else {
gatewayHost := conf.GetGatewaySafe(gateway)
err := prepareHostControlPath(host, gatewayHost)
if err != nil {
return err
}
if host.ProxyCommand == "" {
host.ProxyCommand = "nc %h %p"
}
// FIXME: dynamically add "-v" flags
if err = hostPrepare(host); err != nil {
return err
}
command := "ssh %name -- " + host.ExpandString(host.ProxyCommand)
Logger.Debugf("Using gateway '%s': %s", gateway, command)
err = proxyCommand(gatewayHost, command)
if err == nil {
return nil
}
Logger.Errorf("Cannot use gateway '%s': %v", gateway, err)
}
}
return fmt.Errorf("No such available gateway")
}
Logger.Debugf("Connecting without gateway")
return proxyDirect(host)
}
func hostPrepare(host *config.Host) error {
if host.HostName == "" {
host.HostName = host.Name()
}
if len(host.ResolveNameservers) > 0 {
Logger.Debugf("Resolving host: '%s' using nameservers %s", host.HostName, host.ResolveNameservers)
// FIXME: resolve using custom dns server
results, err := net.LookupAddr(host.HostName)
if err != nil {
return err
}
if len(results) > 0 {
host.HostName = results[0]
}
Logger.Debugf("Resolved host is: %s", host.HostName)
}
if host.ResolveCommand != "" {
command := host.ExpandString(host.ResolveCommand)
Logger.Debugf("Resolving host: %q using command: %q", host.HostName, command)
args, err := shlex.Split(command)
if err != nil {
return err
}
cmd := exec.Command(args[0], args[1:]...)
var stdout bytes.Buffer
var stderr bytes.Buffer
cmd.Stdout = &stdout
cmd.Stderr = &stderr
if err := cmd.Run(); err != nil {
Logger.Errorf("ResolveCommand failed: %s", stderr.String())
return err
}
host.HostName = strings.TrimSpace(fmt.Sprintf("%s", stdout.String()))
Logger.Debugf("Resolved host is: %s", host.HostName)
}
return nil
}
func hostPrepare(host *config.Host) error {
if host.HostName == "" {
host.HostName = host.Name()
}
if len(host.ResolveNameservers) > 0 {
Logger.Debugf("Resolving host: '%s' using nameservers %s", host.HostName, host.ResolveNameservers)
// FIXME: resolve using custom dns server
results, err := net.LookupAddr(host.HostName)
if err != nil {
return err
}
if len(results) > 0 {
host.HostName = results[0]
}
Logger.Debugf("Resolved host is: %s", host.HostName)
}
if host.ResolveCommand != "" {
command := host.ExpandString(host.ResolveCommand)
Logger.Debugf("Resolving host: %q using command: %q", host.HostName, command)
args, err := shlex.Split(command)
if err != nil {
return err
}
out, err := exec.Command(args[0], args[1:]...).Output()
if err != nil {
return err
}
host.HostName = strings.TrimSpace(fmt.Sprintf("%s", out))
Logger.Debugf("Resolved host is: %s", host.HostName)
}
return nil
}