fix write files and deprecated calls

ssh.go

@@ -4,7 +4,6 @@ import (
 	"encoding/binary"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"log"
 	"net"
 	"os"
@@ -24,7 +23,7 @@ func startSSH(cfg *config.Config) {
 		PublicKeyCallback: sshCheckPubkey,
 	}
 
-	pkBytes, err := ioutil.ReadFile("/id_rsa") // TODO configurable
+	pkBytes, err := os.ReadFile("/id_rsa") // TODO configurable
 	if err != nil {
 		fatalf("ssh: failed to load private key: %v", err)
 	}