Run multiple commands on Cisco using golang crypto/ssh

I have the following code pieced together that will let me send read and write to the ssh console of a Cisco box but I am currently not sure how to send multiple commands in the same session.

I am including the entire program in order to server as a starting point for others attempting the same thing in the future, I could not find a working example specifically for Golang<->Cisco.

package main
import (
"fmt"
"io"
"io/ioutil"
"net"
"os"
//"strings"
"golang.org/x/crypto/ssh"
"golang.org/x/crypto/ssh/agent"
)
type SSHCommand struct {
Stdin  io.Reader
Stdout io.Writer
Stderr io.Writer
}
type SSHClient struct {
Config *ssh.ClientConfig
Host   string
Port   int
}
func (client *SSHClient) RunCommand(cmd *SSHCommand) error {
var (
session *ssh.Session
err     error
)
if session, err = client.newSession(); err != nil {
return err
}
defer session.Close()
if err = client.prepareCommand(session, cmd); err != nil {
return err
}
err = session.Run("en\r")
return err
}
func (client *SSHClient) prepareCommand(session *ssh.Session, cmd *SSHCommand) error {
if cmd.Stdin != nil {
stdin, err := session.StdinPipe()
if err != nil {
return fmt.Errorf("Unable to setup stdin for session: %v", err)
}
go io.Copy(stdin, cmd.Stdin)
}
if cmd.Stdout != nil {
stdout, err := session.StdoutPipe()
if err != nil {
return fmt.Errorf("Unable to setup stdout for session: %v", err)
}
go io.Copy(cmd.Stdout, stdout)
}
if cmd.Stderr != nil {
stderr, err := session.StderrPipe()
if err != nil {
return fmt.Errorf("Unable to setup stderr for session: %v", err)
}
go io.Copy(cmd.Stderr, stderr)
}
return nil
}
func (client *SSHClient) newSession() (*ssh.Session, error) {
connection, err := ssh.Dial("tcp", fmt.Sprintf("%s:%d", client.Host, client.Port), client.Config)
if err != nil {
return nil, fmt.Errorf("Failed to dial: %s", err)
}
session, err := connection.NewSession()
if err != nil {
return nil, fmt.Errorf("Failed to create session: %s", err)
}
modes := ssh.TerminalModes{
// ssh.ECHO:          0,     // disable echoing
ssh.TTY_OP_ISPEED: 14400, // input speed = 14.4kbaud
ssh.TTY_OP_OSPEED: 14400, // output speed = 14.4kbaud
}
if err := session.RequestPty("xterm", 0, 200, modes); err != nil {
session.Close()
return nil, fmt.Errorf("request for pseudo terminal failed: %s", err)
}
return session, nil
}
func SSHAgent() ssh.AuthMethod {
if sshAgent, err := net.Dial("unix", os.Getenv("SSH_AUTH_SOCK")); err == nil {
return ssh.PublicKeysCallback(agent.NewClient(sshAgent).Signers)
}
return nil
}
func main() {
sshConfig := &ssh.ClientConfig{
User: "admin",
Auth: []ssh.AuthMethod{
ssh.Password("password"),
},
}
sshConfig.Ciphers = []string{"aes128-cbc"}
client := &SSHClient{
Config: sshConfig,
Host:   "10.10.10.10",
Port:   22,
}
cmd := &SSHCommand{
Stdin:  os.Stdin,
Stdout: os.Stdout,
Stderr: os.Stderr,
}
fmt.Printf("Running commands\n")
if err := client.RunCommand(cmd); err != nil {
fmt.Fprintf(os.Stderr, "command run error: %s\n", err)
os.Exit(1)
}
}

As you can see I have hard coded the "en" command in session.Run().
If I add a command after that by simply doing:

err = session.Run("en\r")
err = session.Run("password\r")

It gets ignored. Reading https://godoc.org/golang.org/x/crypto/ssh#Session.Shell tells me that this is by design. So my question is : How to set up something that lets me enter commands, read output, parse it, and enter more commands based on that output?

Once I wrap my head around this, I plan on parsing routing tables and issuing commands in response. IE, if route X is missing, add it.

This might not be idiomatic go, I am still learning. I wrote this a while ago to get backups off switches but I think it does what you are asking how to do:

https://github.com/plod/goSwitchBackup/blob/master/main.go

func writeBuff(command string, sshIn io.WriteCloser) (int, error) {
returnCode, err := sshIn.Write([]byte(command + "\r"))
return returnCode, err
}