POC IP range enumeration

add.go

@@ -7,6 +7,8 @@ func Add(hostname string, owner string, description string) {//, publicKey strin
 	presharedKey := GenerateJSONKey()
 	publicKey := privateKey.PublicKey()
 
+	conf.ChooseIP()
+
 	peer := PeerConfig{
 		Owner: owner,
 		Hostname: hostname,

go.mod

@@ -3,6 +3,7 @@ module github.com/naggie/dsnet
 go 1.13
 
 require (
+	github.com/mikioh/ipaddr v0.0.0-20190404000644-d465c8ab6721
 	golang.org/x/tools v0.0.0-20200302155637-b1e4e04173e0 // indirect
 	golang.zx2c4.com/wireguard/wgctrl v0.0.0-20200205215550-e35592f146e4
 )

go.sum

@@ -8,6 +8,7 @@ github.com/mdlayher/genetlink v1.0.0/go.mod h1:0rJ0h4itni50A86M2kHcgS85ttZazNt7a
 github.com/mdlayher/netlink v0.0.0-20190409211403-11939a169225/go.mod h1:eQB3mZE4aiYnlUsyGGCOpPETfdQq4Jhsgf1fk3cwQaA=
 github.com/mdlayher/netlink v1.0.0/go.mod h1:KxeJAFOFLG6AjpyDkQ/iIhxygIUKD+vcwqcnu43w/+M=
 github.com/mdlayher/netlink v1.1.0/go.mod h1:H4WCitaheIsdF9yOYu8CFmCgQthAPIWZmcKp9uZHgmY=
+github.com/mikioh/ipaddr v0.0.0-20190404000644-d465c8ab6721 h1:RlZweED6sbSArvlE924+mUcZuXKLBHA35U7LN621Bws=
 github.com/mikioh/ipaddr v0.0.0-20190404000644-d465c8ab6721/go.mod h1:Ickgr2WtCLZ2MDGd4Gr0geeCH5HybhRJbonOgQpvSxc=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20191002192127-34f69633bfdc/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=

types.go

@@ -6,6 +6,7 @@ import (
 	"net"
 	"strings"
 	"time"
+	"fmt"
 
 	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
 )
@@ -81,6 +82,30 @@ func (conf *DsnetConfig) MustAddPeer(peer PeerConfig) {
 	conf.Peers = append(conf.Peers, peer)
 }
 
+// choose a free IP for a new Peer
+func (conf DsnetConfig) ChooseIP() net.IP {
+	network := conf.Network.IPNet
+	ones, bits := network.Mask.Size()
+	zeros := bits - ones
+	min := 1
+	max := (1 << zeros) -1
+
+	for i := min; i <= max; i++ {
+		IP := make(net.IP, len(network.IP))
+		copy(IP, network.IP)
+
+		// OR the host part with the network part
+		for j := 0; j < len(IP); j++ {
+			shift := (len(IP) - j - 1) * 8
+			IP[j] = IP[j] | byte(i>>shift)
+		}
+
+		fmt.Println(IP)
+	}
+
+	return net.IP{}
+}
+
 type Dsnet struct {
 	Name       string
 	PrivateKey wgtypes.Key