Adding additional error checks

andy-trimble · Jun 2, 2021 · db03eef · db03eef
1 parent 4f444d9
commit db03eef
Showing 1 changed file with 13 additions and 0 deletions.
diff --git a/main.go b/main.go
@@ -6,6 +6,7 @@ import (
 	"log"
 	"net"
 	"os"
+	"strconv"
 	"strings"
 	"text/tabwriter"
 )
@@ -39,6 +40,18 @@ func main() {
 		ipRange = strings.TrimSpace(ipRange)
 	}
 
+	spl := strings.Split(ipRange, "/")
+	if len(spl) < 2 {
+		log.Fatal("bad cidr")
+	}
+	r, err := strconv.Atoi(spl[1])
+	if err != nil {
+		log.Fatal(err)
+	}
+	if r < 8 {
+		log.Fatal("range cannot be smaller than 8")
+	}
+
 	addr, network, err := net.ParseCIDR(ipRange)
 	if err != nil {
 		log.Fatal(err)