Go で PEM/キーを使用して SSH を認証するにはどうすればよいですか?

<code class="go">package main

import (
    "crypto/x509"
    "fmt"
    "io/ioutil"
    "log"
    "net"
    "os"

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

func main() {
    // Parse the private key
    key, err := ioutil.ReadFile("mykey.pem")
    if err != nil {
        log.Fatal(err)
    }

    // Get the signer
    signer, err := ssh.ParsePrivateKey(key)
    if err != nil {
        log.Fatal(err)
    }

    // Switch to using an agent if SSH_AUTH_SOCK is set
    if authSock := os.Getenv("SSH_AUTH_SOCK"); authSock != "" {
        sock, err := net.Dial("unix", authSock)
        if err != nil {
            log.Fatalf("Failed to connect to agent: %v", err)
        }
        _ = sock
        // TODO(harsh)
        // Implement working with agent.
    }

    // Create the AuthMethod
    authMethods := []ssh.AuthMethod{ssh.PublicKeys(signer)}

    // Set up the ClientConfig
    clientConfig := &ssh.ClientConfig{
        User:            "username",
        Auth:            authMethods,
        HostKeyCallback: ssh.InsecureIgnoreHostKey(),
    }

    // Dial the connection
    client, err := ssh.Dial("tcp", "aws-hostname:22", clientConfig)
    if err != nil {
        log.Fatal(err)
    }

    // Create a session
    session, err := client.NewSession()
    if err != nil {
        log.Fatal(err)
    }

    // Execute a command
    output, err := session.Output("whoami")
    if err != nil {
        log.Fatal(err)
    }

    fmt.Println("Output:", string(output))

    // Close the session and client
    _ = session.Close()
    _ = client.Close()
}</code>