explicitly dont handle returns in certain places

main.go

@@ -1,16 +1,16 @@
 package main
+
 import (
 	"fmt"
+	"net"
+	"net/http"
 	"os"
 	"os/exec"
-  "strings"
-  "net/http"
-  "net"
 	"strconv"
+	"strings"
 
 	log "github.com/sirupsen/logrus"
 	flag "github.com/spf13/pflag"
-
 )
 
 var logstdout = log.New()
@@ -92,20 +92,38 @@ func runner(remoteip string, command string, args... string) string{
 	return string(cmd)
 }
 
-func validatehosts(hosts []string) []string{
-  var valid []string
+func validatehosts(hosts []string) ([]string, []string) {
+	var validhosts []string
+	var validports []string
 	for _, host := range hosts {
+		split := strings.Split(host, "_")
+		host = split[0]
 		if hostparse := net.ParseIP(host); hostparse != nil {
 			if (net.IP.IsPrivate(hostparse) || net.IP.IsLoopback(hostparse)) && allowprivate {
-        valid = append(valid, host)
+				validhosts = append(validhosts, host)
 			} else if !(net.IP.IsPrivate(hostparse) || net.IP.IsLoopback(hostparse)) {
-        valid = append(valid, host)
+				validhosts = append(validhosts, host)
 			}
 		} else if _, err := net.LookupIP(host); err == nil {
-      valid = append(valid, host)
+			validhosts = append(validhosts, host)
+		} else {
+			continue
+		}
+
+		var port string
+		if len(split) > 1 {
+			port = split[1]
+			_, err := strconv.Atoi(port) // validate if port is just an int
+			if err == nil {
+				validports = append(validports, port)
+			} else {
+				validports = append(validports, "0")
+			}
+		} else {
+			validports = append(validports, "0")
 		}
 	}
-  return valid
+	return validhosts, validports
 }
 
 func parseopts(options []string, cmdopts map[string]string) []string {
@@ -119,7 +137,7 @@ func parseopts(options []string, cmdopts map[string]string) []string{
 func prerunner(req *http.Request, cmd string, cmdopts map[string]string, defaultopts []string) string {
 	geturl := strings.Split(req.URL.String(), "/")
 	targets := strings.Split(geturl[2], ",")
-  hosts := validatehosts(targets)
+	hosts, ports := validatehosts(targets)
 	var opts []string
 	opts = append(opts, defaultopts...)
 	if len(geturl) > 3 && len(geturl[3]) > 0 {
@@ -134,10 +152,13 @@ func prerunner(req *http.Request, cmd string, cmdopts map[string]string, default
 	} else {
 		remoteaddr = req.RemoteAddr
 	}
-  for _, host := range hosts {
-    args = append(args, opts...)
-    args = append(args, host)
-    res = fmt.Sprint(res, runner(remoteaddr, cmd, args...), "\n")
+	for i, host := range hosts {
+		runargs := append(args, opts...)
+		if ports[i] != "0" && cmd == "nping" {
+			runargs = append(runargs, "-p"+ports[i])
+		}
+		runargs = append(runargs, host)
+		res = fmt.Sprint(res, runner(remoteaddr, cmd, runargs...), "\n")
 	}
 	return res
 }
@@ -152,9 +173,9 @@ func ping(w http.ResponseWriter, req *http.Request) {
 	defaultopts = append(defaultopts, "-c10")
 	res := prerunner(req, cmd, cmdopts, defaultopts)
 	if strings.TrimSpace(res) == "" {
-    fmt.Fprintln(w, http.StatusInternalServerError)
+		http.Error(w, "500: Internal Server Error", http.StatusInternalServerError)
 	} else {
-    fmt.Fprint(w, strings.TrimSpace(res), "\n")
+		_, _ = fmt.Fprint(w, strings.TrimSpace(res), "\n")
 	}
 }
 
@@ -168,9 +189,9 @@ func mtr(w http.ResponseWriter, req *http.Request) {
 	defaultopts = append(defaultopts, "-r", "-w", "-c10")
 	res := prerunner(req, cmd, cmdopts, defaultopts)
 	if strings.TrimSpace(res) == "" {
-    fmt.Fprintln(w, http.StatusInternalServerError)
+		http.Error(w, "500: Internal Server Error", http.StatusInternalServerError)
 	} else {
-    fmt.Fprint(w, strings.TrimSpace(res), "\n")
+		_, _ = fmt.Fprint(w, strings.TrimSpace(res), "\n")
 	}
 }
 
@@ -184,9 +205,25 @@ func traceroute(w http.ResponseWriter, req *http.Request) {
 	//defaultopts = append(defaultopts) // no default options for traceroute
 	res := prerunner(req, cmd, cmdopts, defaultopts)
 	if strings.TrimSpace(res) == "" {
-    fmt.Fprintln(w, http.StatusInternalServerError)
+		http.Error(w, "500: Internal Server Error", http.StatusInternalServerError)
 	} else {
-    fmt.Fprint(w, strings.TrimSpace(res), "\n")
+		_, _ = fmt.Fprint(w, strings.TrimSpace(res), "\n")
+	}
+}
+
+func nping(w http.ResponseWriter, req *http.Request) {
+	cmd := "nping"
+	cmdopts := map[string]string{
+		"4": "-4", "6": "-6", "u": "--udp", "t": "--tcp-connect", "v": "-v", "c1": "-c1", "c3": "-c3", "c5": "-c5",
+		"force4": "-4", "force6": "-6", "udp": "--udp", "tcp": "--tcp-connect", "verbose": "-v", "count1": "-c1", "count3": "-c3", "count5": "-c5",
+	}
+	var defaultopts []string
+	defaultopts = append(defaultopts, "-c3")
+	res := prerunner(req, cmd, cmdopts, defaultopts)
+	if strings.TrimSpace(res) == "" {
+		http.Error(w, "500: Internal Server Error", http.StatusInternalServerError)
+	} else {
+		_, _ = fmt.Fprint(w, strings.TrimSpace(res), "\n")
 	}
 }
 
@@ -195,7 +232,8 @@ func main() {
 	http.HandleFunc("/mtr/", mtr)
 	http.HandleFunc("/tracert/", traceroute)
 	http.HandleFunc("/traceroute/", traceroute)
+	http.HandleFunc("/nping/", nping)
 	logstdout.Info("Serving on :", listenport)
 	logfile.Info("Serving on :", listenport)
-  http.ListenAndServe(fmt.Sprint(":", listenport), nil)
+	_ = http.ListenAndServe(fmt.Sprint(":", listenport), nil)
 }