From 73f887087a04806bbd8e5b378ec0148b94616bae Mon Sep 17 00:00:00 2001
From: evilsocket <evilsocket@gmail.com>
Date: Thu, 1 Feb 2018 19:45:09 +0100
Subject: [PATCH] fix: fixed a bug of the probe and recon algos which prevented
 targets from being removed once offline

---
 modules/net_probe.go |  2 --
 modules/net_recon.go | 28 +++++++++++-----------------
 net/arp.go           | 12 ------------
 session/targets.go   |  2 +-
 4 files changed, 12 insertions(+), 32 deletions(-)

diff --git a/modules/net_probe.go b/modules/net_probe.go
index 5d566a6b..4d774986 100644
--- a/modules/net_probe.go
+++ b/modules/net_probe.go
@@ -60,8 +60,6 @@ func (p *Prober) shouldProbe(ip net.IP) bool {
 		return false
 	} else if addr == p.Session.Gateway.IpAddress {
 		return false
-	} else if p.Session.Targets.Has(addr) == true {
-		return false
 	}
 	return true
 }
diff --git a/modules/net_recon.go b/modules/net_recon.go
index dac7fa0d..93887c83 100644
--- a/modules/net_recon.go
+++ b/modules/net_recon.go
@@ -102,27 +102,21 @@ func (d *Discovery) checkShared(new net.ArpTable) {
 }
 
 func (d *Discovery) runDiff() {
-	var new net.ArpTable = make(net.ArpTable)
+	// check for endpoints who disappeared
 	var rem net.ArpTable = make(net.ArpTable)
-
-	if d.before != nil {
-		new = net.ArpDiff(d.current, d.before)
-		rem = net.ArpDiff(d.before, d.current)
-	} else {
-		new = d.current
+	for mac, t := range d.Session.Targets.Targets {
+		if _, found := d.current[mac]; found == false {
+			rem[mac] = t.IpAddress
+		}
 	}
 
-	if len(new) > 0 || len(rem) > 0 {
-		d.checkShared(new)
+	for mac, ip := range rem {
+		d.Session.Targets.Remove(ip, mac)
+	}
 
-		// refresh target pool
-		for ip, mac := range rem {
-			d.Session.Targets.Remove(ip, mac)
-		}
-
-		for ip, mac := range new {
-			d.Session.Targets.AddIfNotExist(ip, mac)
-		}
+	// now check for new friends ^_^
+	for ip, mac := range d.current {
+		d.Session.Targets.AddIfNotExist(ip, mac)
 	}
 }
 
diff --git a/net/arp.go b/net/arp.go
index 35195d63..b86f7cbe 100644
--- a/net/arp.go
+++ b/net/arp.go
@@ -13,18 +13,6 @@ var (
 	arpTable     = make(ArpTable)
 )
 
-func ArpDiff(current, before ArpTable) ArpTable {
-	diff := make(ArpTable)
-	for ip, mac := range current {
-		_, found := before[ip]
-		if !found {
-			diff[ip] = mac
-		}
-	}
-
-	return diff
-}
-
 func ArpLookup(iface string, address string, refresh bool) (string, error) {
 	// Refresh ARP table if first run or if a force refresh has been instructed.
 	if ArpParsed() == false || refresh == true {
diff --git a/session/targets.go b/session/targets.go
index 6185de59..bccb8e2e 100644
--- a/session/targets.go
+++ b/session/targets.go
@@ -12,7 +12,7 @@ import (
 	"github.com/evilsocket/bettercap-ng/net"
 )
 
-const TargetsDefaultTTL = 2
+const TargetsDefaultTTL = 10
 const TargetsAliasesFile = "~/bettercap.aliases"
 
 type Targets struct {