From 12e815872510707c3e74fbb89fd3f71f1648ef8f Mon Sep 17 00:00:00 2001
From: Callan Bryant <callan.bryant@gmail.com>
Date: Mon, 2 Mar 2020 19:02:09 +0000
Subject: [PATCH] avoid broadcast addr

---
 add.go   | 4 +++-
 types.go | 4 ++--
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/add.go b/add.go
index 15ee751..62718e4 100644
--- a/add.go
+++ b/add.go
@@ -7,7 +7,9 @@ func Add(hostname string, owner string, description string) {//, publicKey strin
 	presharedKey := GenerateJSONKey()
 	publicKey := privateKey.PublicKey()
 
-	conf.ChooseIP()
+	IP, err := conf.ChooseIP()
+
+	check(err)
 
 	peer := PeerConfig{
 		Owner: owner,
diff --git a/types.go b/types.go
index b684c53..be051ff 100644
--- a/types.go
+++ b/types.go
@@ -100,8 +100,8 @@ func (conf DsnetConfig) ChooseIP() (net.IP, error) {
 	network := conf.Network.IPNet
 	ones, bits := network.Mask.Size()
 	zeros := bits - ones
-	min := 1
-	max := (1 << zeros) -1
+	min := 1  // avoids network addr
+	max := (1 << zeros) -2  // avoids broadcast addr + overflow
 
 	for i := min; i <= max; i++ {
 		IP := make(net.IP, len(network.IP))