golang ssh 由 nc 替换 ssh ProxyCommand

Question

我打算实现一个 golang 版本的 ssh 客户端来通过堡垒连接到目标服务器。但不幸的是，我在替换 nc 代理时失败了。

在我本地的 ssh 配置:

Host bastion
    HostName xxx.xxx.xxx.xxx
    User ec2-user
    IdentityFile ~/.ssh/xxx-bastion.pem
Host 10.0.*.*
  User ec2-user
  IdentityFile ~/.ssh/xxx-dest.pem
  ProxyCommand ssh -q bastion "nc -w 3600 %h %p"

我的 golang 实现如下:

var(
    Bastion="xxx.xxx.xxx.xxx:22"
    Target="xxx.xxx.xxx.xxx:22"
    BastionPem ="/Users/me/.ssh/xxx-bastion.pem"
    DestPem ="/Users/me/.ssh/xxx-dest.pem"
    Timeout=30*time.Second
)

func BastionConfig() (*ssh.ClientConfig,error){
    pemBytes, err := ioutil.ReadFile(BastionPem)
    if err != nil {
        log.Fatal(err)
    }
    signer, err := ssh.ParsePrivateKey(pemBytes)
    if err != nil {
        log.Fatalf("parse key failed:%v", err)
    }
    config := &ssh.ClientConfig{
        User: "ec2-user",
        Auth: []ssh.AuthMethod{ssh.PublicKeys(signer)},
        Timeout:Timeout,
    }
    return config,err
}


func DestConfig() (*ssh.ClientConfig,error){
    pemBytes, err := ioutil.ReadFile(TargetPem)
    if err != nil {
        log.Fatal(err)
    }
    signer, err := ssh.ParsePrivateKey(pemBytes)
    if err != nil {
        log.Fatalf("parse key failed:%v", err)
    }
    config := &ssh.ClientConfig{
        User: "ec2-user",
        Auth: []ssh.AuthMethod{ssh.PublicKeys(signer)},
        Timeout:Timeout,
    }
    return config,err
}
func Connect(){
    config,_:= BastionConfig()
    bClient, err := ssh.Dial("tcp", Bastion, config)
    if err != nil {
        log.Fatal("dial bastion error:",err)
    }
    log.Println("dial bastion ok...")
    // Dial a connection to the service host, from the bastion
    conn, err := bClient.Dial("tcp", Target)
    if err != nil {
        log.Fatal("dial target error",err)
    }
    targetConfig,_:= DestConfig()
    ncc, chans, reqs, err := ssh.NewClientConn(conn, Target, targetConfig)
    if err != nil {
        log.Fatal("new target conn error:",err)
    }
    log.Printf("target conn[%s] ok\n",Target)

    targetClient := ssh.NewClient(ncc, chans, reqs)
    if err != nil {
        log.Fatalf("target ssh error:%v",err)
    }

    session,err:=targetClient.NewSession()

    if err!=nil{
        log.Fatalf("session failed:%v",err)
    }
    defer session.Close()
    var stdoutBuf bytes.Buffer
    session.Stdout = &stdoutBuf
    err = session.Run("hostname")
    if err != nil {
        log.Fatalf("Run failed:%v", err)
    }
    log.Printf(">%s", stdoutBuf)

}

但是我得到的是堡垒服务器的主机名，而不是我的目标服务器，我是不是错过了引导目标服务器的输入/输出之类的，我不知道我的代码哪里错了，谁能给我一些方向。

非常感谢。

Answer 1

试试这个包 https://github.com/appleboy/easyssh-proxy

ssh := &easyssh.MakeConfig{
    User:    "drone-scp",
    Server:  "localhost",
    Port:    "22",
    KeyPath: "./tests/.ssh/id_rsa",
    Proxy: easyssh.DefaultConfig{
        User:    "drone-scp",
        Server:  "localhost",
        Port:    "22",
        KeyPath: "./tests/.ssh/id_rsa",
    },
}