Function connectOperator

cmd/install.go:343–395

connectOperator Try SSH agent without parsing key files, will succeed if the user has already added a key to the SSH Agent, or if using a configured smartcard. If the initial connection attempt fails fall through to the using the supplied/default private key file DoneFunc should be called by the c

(user string, address string, sshKeyPath string)

// the supplied/default private key file
// DoneFunc should be called by the caller to close the SSH connection when done
func connectOperator(user string, address string, sshKeyPath string) (*operator.SSHOperator, DoneFunc, bool, error) {
	var sshOperator *operator.SSHOperator
	var initialSSHErr error
	var closeSSHAgentFunc func() error

	doneFunc := func() {
		if sshOperator != nil {
			sshOperator.Close()
		}
		if closeSSHAgentFunc != nil {
			closeSSHAgentFunc()
		}
	}

	if runtime.GOOS != "windows" {
		var sshAgentAuthMethod ssh.AuthMethod
		sshAgentAuthMethod, initialSSHErr = sshAgentOnly()
		if initialSSHErr == nil {

			config := &ssh.ClientConfig{
				User:            user,
				Auth:            []ssh.AuthMethod{sshAgentAuthMethod},
				HostKeyCallback: ssh.InsecureIgnoreHostKey(),
			}

			sshOperator, initialSSHErr = operator.NewSSHOperator(address, config)
		}
	} else {
		initialSSHErr = errors.New("ssh-agent unsupported on windows")
	}

	if initialSSHErr != nil {
		publicKeyFileAuth, closeSSHAgent, err := loadPublickey(sshKeyPath)
		if err != nil {
			return nil, nil, true, fmt.Errorf("unable to load the ssh key with path %q: %w", sshKeyPath, err)
		}

		defer closeSSHAgent()

		config := &ssh.ClientConfig{
			User:            user,
			Auth:            []ssh.AuthMethod{publicKeyFileAuth},
			HostKeyCallback: ssh.InsecureIgnoreHostKey(),
		}

		sshOperator, err = operator.NewSSHOperator(address, config)
		if err != nil {
			return nil, nil, true, fmt.Errorf("unable to connect to %s over ssh: %w", address, err)
		}
	}

	return sshOperator, doneFunc, false, nil
}

func sshAgentOnly() (ssh.AuthMethod, error) {
	sshAgent, err := net.Dial("unix", os.Getenv("SSH_AUTH_SOCK"))