sshutil
A single-dependency utility package that provides a net/http style SSH server.
sshutil is part of the Smallstep crypto suite (step, step-ca, etc.).
Why sshutil?
The sshutil package depends solely on the Go x/crypto module.
The x/crypto/ssh package provides convenient support for the ssh wire protocol, the ssh authentication protocol, and the ssh connection protocol.
SSH, and thus the x/crypto implementation, is natually scoped to a single connection—whereas servers generally need to accept many connections.
A small, but tedious, amount of work is required to implement a full connection-tracking server for use in applications.
sshutil fills in the gap.
Get
$ go get go.step.sm/sshutilExamples
Example can be found in the examples directory. Run with:
$ go run go.step.sm/example/<name>
$ go run ./example/<name>Hello SSH
package main
import "go.step.sm/sshutil"
func() hello(stream sshutil.Session) {
stream.Terminal.Write([]byte("Hello SSH\n")
}
func main() {
server := &sshutil.Server{Addr: ":2022"}
server.Channel("session", sshutil.NewSessionHandler(hello))
server.ListenAndServe()
}Output:
$ go run ./example/hello
$ ssh localhost -p 2022
Hello SSH
Server closed remote connection to localhost.Host Key
Easily configure a persistent host key using sshutil.LoadHostKeyFromFile.
The default session handler is an echo terminal server.
package main
import (
"log"
"go.step.sm/sshutil"
)
func main() {
server := &sshutil.Server{
Addr: ":2022",
Config: sshutil.DefaultServerConfig(),
}
key, err := sshutil.LoadHostKeyFromFile("example/server.key", "")
if err != nil {
log.Fatalf("error loading key: %v", err)
}
server.Config.AddHostKey(key)
err = server.ListenAndServe()
log.Print(err)
}Output:
$ go run ./example/hostkey
$ ssh localhost -p 2022
> echo
echo
> ^D
Client closed connection to localhost.Test
$ go test
