add timeout and flag

config.go

@@ -3,6 +3,7 @@ package main
 import (
 	"fmt"
 	"os"
+	"time"
 
 	"github.com/urfave/cli"
 )
@@ -13,6 +14,7 @@ type configServe struct {
 	logsLocation    string
 	bindAddr        string
 	debug, demo     bool
+	idleTimeout     time.Duration
 }
 
 func parseServeConfig(c *cli.Context) (*configServe, error) {
@@ -24,6 +26,7 @@ func parseServeConfig(c *cli.Context) (*configServe, error) {
 		debug:        c.Bool("debug"),
 		demo:         c.Bool("demo"),
 		logsLocation: c.String("logs-location"),
+		idleTimeout:  c.Duration("idle-timeout"),
 	}
 	switch len(ret.aesKey) {
 	case 0, 16, 24, 32:

main.go

@@ -3,6 +3,7 @@ package main
 import (
 	"fmt"
 	"log"
+	"math"
 	"math/rand"
 	"net"
 	"os"
@@ -79,6 +80,11 @@ func main() {
 					Value: "./log",
 					Usage: "Store user session files",
 				},
+				cli.DurationFlag{
+					Name:  "idle-timeout",
+					Value: 0,
+					Usage: "Duration before an inactive connection is timed out (0 to disable)",
+				},
 			},
 		}, {
 			Name:   "healthcheck",
@@ -144,6 +150,12 @@ func server(c *configServe) (err error) {
 		Version:        fmt.Sprintf("sshportal-%s", Version),
 		ChannelHandler: channelHandler,
 	}
+	if c.idleTimeout != 0 {
+		srv.IdleTimeout = c.idleTimeout
+		// gliderlabs/ssh requires MaxTimeout to be non-zero if we want to use IdleTimeout.
+		// So, set it to the max value, because we don't want a max timeout.
+		srv.MaxTimeout = math.MaxInt64
+	}
 
 	for _, opt := range []ssh.Option{
 		// custom PublicKeyAuth handler