ssh.go

package main

import (
  "bytes"
  "io/ioutil"
  "log"
  "net"
  "os"

  "golang.org/x/crypto/ssh"
  "golang.org/x/crypto/ssh/agent"
)

// Get default location of a private key
func privateKeyPath() string {
  return os.Getenv("HOME") + "/.ssh/id_rsa"
}

// Get private key for ssh authentication
func parsePrivateKey(keyPath string) (ssh.Signer, error) {
  buff, _ := ioutil.ReadFile(keyPath)
  return ssh.ParsePrivateKey(buff)
}

func makeSshConfig(user string) (*ssh.ClientConfig, error) {
  /*key, err := parsePrivateKey(privateKeyPath())
  if err != nil {
    return nil, err
  }*/

  socket := os.Getenv("SSH_AUTH_SOCK")
  conn, err := net.Dial("unix", socket)
  if err != nil {
    return nil, err
  }
  agentClient := agent.NewClient(conn)

  config := ssh.ClientConfig{
    User: user,
    Auth: []ssh.AuthMethod{
      //ssh.PublicKeys(key),
      ssh.PublicKeysCallback(agentClient.Signers),
    },
  }

  return &config, nil
}

func main() {
  config, err := makeSshConfig("erik")
  if err != nil {
    log.Fatalf("[ERR] %v", err)
  }

  client, err := ssh.Dial("tcp", "homepage:22", config)
  if err != nil {
    log.Fatalf("[ERR] %v", err)
  }

  session, err := client.NewSession()
  if err != nil {
    log.Fatalf("[ERR] %v", err)
  }
  defer session.Close()

  var b bytes.Buffer
  session.Stdout = &b
  if err := session.Run("/bin/ps auxf"); err != nil {
    log.Fatalf("[ERR] %v", err)
  }
  log.Println(b.String())
}