SSH握手抱怨缺少主机密钥

Question

我试图连接到远程主机，并检查文件是否存在 在这个阶段，我想只是连接，但我得到了一个错误：

2017/08/01 18:16:39 unable to connect: ssh: handshake failed: ssh: required host key was nil 

我试图找出他人是否有我的问题，但我无法找到。

我明白，我需要以某种方式检查knowns_hosts的过程，但我只是无法弄清楚如何...

var hostKey ssh.PublicKey 
    // A public key may be used to authenticate against the remote 
    // server by using an unencrypted PEM-encoded private key file. 
    // 
    // If you have an encrypted private key, the crypto/x509 package 
    // can be used to decrypt it. 
    key, err := ioutil.ReadFile("/home/user/.ssh/id_rsa") 
    if err != nil { 
     log.Fatalf("unable to read private key: %v", err) 
    } 

    // Create the Signer for this private key. 
    signer, err := ssh.ParsePrivateKey(key) 
    if err != nil { 
     log.Fatalf("unable to parse private key: %v", err) 
    } 

    config := &ssh.ClientConfig{ 
     User: "user", 
     Auth: []ssh.AuthMethod{ 
      // Use the PublicKeys method for remote authentication. 
      ssh.PublicKeys(signer), 
     }, 
     HostKeyCallback: ssh.FixedHostKey(hostKey), 
    } 

    // Connect to the remote server and perform the SSH handshake. 
    client, err := ssh.Dial("tcp", "host.com:22", config) 
    if err != nil { 
     log.Fatalf("unable to connect: %v", err) 
    } 
    defer client.Close() 
} 

Answer 1

这里你正在寻找：

func getHostKey(host string) (ssh.PublicKey, error) { 
    file, err := os.Open(filepath.Join(os.Getenv("HOME"), ".ssh", "known_hosts")) 
    if err != nil { 
     return nil, err 
    } 
    defer file.Close() 

    scanner := bufio.NewScanner(file) 
    var hostKey ssh.PublicKey 
    for scanner.Scan() { 
     fields := strings.Split(scanner.Text(), " ") 
     if len(fields) != 3 { 
      continue 
     } 
     if strings.Contains(fields[0], host) { 
      var err error 
      hostKey, _, _, _, err = ssh.ParseAuthorizedKey(scanner.Bytes()) 
      if err != nil { 
       return nil, errors.New(fmt.Sprintf("error parsing %q: %v", fields[2], err)) 
      } 
      break 
     } 
    } 

    if hostKey == nil { 
     return nil, errors.New(fmt.Sprintf("no hostkey for %s", host)) 
    } 
    return hostKey, nil 
} 

然后将您的hostKey定义行替换为

hostKey, err := getHostKey("host.com") 
if err != nil { 
    log.Fatal(err) 
} 

有关该主题的更多信息：

• official sample这里我把代码中的某些部分
• why a hostKey is necessary now