SSH from Golang code successfully but hangs

user_13505905 0
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I used the following go code to open an ssh connection to a remote host

func ssh(keyname string, user string, address string) {
    cmd := exec.Command("ssh", "-tt", user+"@"+address, "-i", "~/"+keyname) 
    cmd.Stderr = os.Stderr
    cmd.Stdout = os.Stdout

    if err := cmd.Run(); err != nil {
        fmt.Println(err.Error())
    }
}

func main() {
    ssh("example.pem", "ubuntu", "192.169.0.1")
}

When i run the code i connect successully to the remote host and get a terminal, but when i type commands it doesn't show any outputs just hangs, tried to ssh normally via my terminal and everything is ok. Not sure if this is from my code or SSH

go ssh
2 Answers

Use following code

package main
import (
    "log"

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

func main() {
    // ssh config
    hostKeyCallback, err := knownhosts.New("/home/debian11/.ssh/known_hosts")
    if err != nil {
        log.Fatal(err)
    }
    config := &ssh.ClientConfig{
        User: "ubuntu",
        Auth: []ssh.AuthMethod{
            ssh.Password("password"),
        },
        HostKeyCallback: hostKeyCallback,
    }
    // connect to ssh server
    conn, err := ssh.Dial("tcp", "192.169.0.1:22", config)
    if err != nil {
        log.Fatal(err)
    }
    defer conn.Close()
}

Above is for password based login. Some changes will be required for certificate based auth.

Further reading:

user_78778570

Assigning os.stdin to Stdin solves this problem, subtle

func ssh(keyname string, user string, address string) {
    cmd := exec.Command("ssh", "-tt", user+"@"+address, "-i", "~/"+keyname)

    cmd.Stdin = os.Stdin
    cmd.Stderr = os.Stderr
    cmd.Stdout = os.Stdout

    if err := cmd.Run(); err != nil {
        fmt.Println(err.Error())
    }
}
user_135059050
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