SSH connectivity using Swift

Question

Recently, I've been trying to make a (very) simple program with Swift that lets you connect to a server through SSH and execute some files. Unfortunately, I could not figure out how to start an SSH session completely within the Swift app. Here is some code that I have written:

var sshConnectCommand = ["-c", "spawn ssh "+sshUsername+"@"+sshHost+"; expect assword:; send "+sshPassword+"\r"]
func sshIn() {
    //starting ssh session
    let sshConnect = NSTask()
    sshConnect.arguments = [testCmd]

    //rerouting output through a pipe
    sshConnect.standardOutput = logAppend

    //launch!
    sshConnect.launch();
}

As you can see, I have used NSTask to try and run the 'expect' command to enter the password and everything. I would like to try and avoid using SSH-keygen as much as possible as this is intended to be used a server that the user does not have any access to.

So, to sum up: How would you connect to SSH without SSH-keygen while remaining completely within the application code?

edit: I should also add, when trying to compile, I get this error: [Swift._SwiftDeferredNSArray fileSystemRepresentation]: unrecognized selector sent to instance 0x600000032500. I'm not sure what this means.

Solution

I've been using something similar to this to ssh into my Raspberry Pi:

func sshIn() {
    let task = CommandLine()
    task.launchPath = "/usr/bin/ssh"
    task.arguments = ["USERNAME@IPADDRESS", "-t", "sudo systemctl stop mediacenter; /opt/vc/bin/tvservice -o"]
    task.launch()
}

-t closes the connection when the commands are finished running, and you can pass in all your commands like so command1; command 2 like where I've got sudo systemctl stop mediacenter; /opt/vc/bin/tvservice -o As for the keygen thing, I don't think you have much of a choice. You can look into locking it down a bit though. Here's a good place to start looking.

Comments

[perhapsmaybeharry]

Thank you for your response. Trying it with your method I still get the nasty 0x600000... error. I'm not sure where that comes from, but according to my logs the program never got past the command. Any idea why this is so?

[The Beanstalk]

I just took out a line that might have been causing problems (forgot to delete it earlier). In which line does the error occur?

[perhapsmaybeharry]

The error occurs at sshConnect.launch() or task.launch() in your example. It's telling me that there was an "unrecognised selector sent to instance 0x6000...".

[The Beanstalk]

It could be something with your arguments array, what's that look like?

[Mark Gerrior]

After the great renaming: NSTask in now Process in Swift.

[CousinCocaine]

After the great great renaming: NSTask that became Process is now CommandLine. So use: let task = CommandLine() git apple-swift

[Radu Ursache]

@CousinCocaine actually by using let task = CommandLine() you'll get 'CommandLine' cannot be constructed because it has no accessible initializers. So keep using let task = Process() which works in Swift 5.5