Function ExampleNewServerConn

tempfork/sshtest/ssh/example_test.go:25–155

()

)

func ExampleNewServerConn() {
	// Public key authentication is done by comparing
	// the public key of a received connection
	// with the entries in the authorized_keys file.
	authorizedKeysBytes, err := os.ReadFile("authorized_keys")
	if err != nil {
		log.Fatalf("Failed to load authorized_keys, err: %v", err)
	}

	authorizedKeysMap := map[string]bool{}
	for len(authorizedKeysBytes) > 0 {
		pubKey, _, _, rest, err := ssh.ParseAuthorizedKey(authorizedKeysBytes)
		if err != nil {
			log.Fatal(err)
		}

		authorizedKeysMap[string(pubKey.Marshal())] = true
		authorizedKeysBytes = rest
	}

	// An SSH server is represented by a ServerConfig, which holds
	// certificate details and handles authentication of ServerConns.
	config := &ssh.ServerConfig{
		// Remove to disable password auth.
		PasswordCallback: func(c ssh.ConnMetadata, pass []byte) (*ssh.Permissions, error) {
			// Should use constant-time compare (or better, salt+hash) in
			// a production setting.
			if c.User() == "testuser" && string(pass) == "tiger" {
				return nil, nil
			}
			return nil, fmt.Errorf("password rejected for %q", c.User())
		},

		// Remove to disable public key auth.
		PublicKeyCallback: func(c ssh.ConnMetadata, pubKey ssh.PublicKey) (*ssh.Permissions, error) {
			if authorizedKeysMap[string(pubKey.Marshal())] {
				return &ssh.Permissions{
					// Record the public key used for authentication.
					Extensions: map[string]string{
						"pubkey-fp": ssh.FingerprintSHA256(pubKey),
					},
				}, nil
			}
			return nil, fmt.Errorf("unknown public key for %q", c.User())
		},
	}

	privateBytes, err := os.ReadFile("id_rsa")
	if err != nil {
		log.Fatal("Failed to load private key: ", err)
	}

	private, err := ssh.ParsePrivateKey(privateBytes)
	if err != nil {
		log.Fatal("Failed to parse private key: ", err)
	}
	config.AddHostKey(private)