Working (but not intensively tested) IPv6 support!

sgfw/dns.go

@@ -65,7 +65,7 @@ func (dc *dnsCache) processDNS(pkt *nfqueue.NFQPacket) {
 	}
 	q := dns.question[0]
 	if q.Qtype == dnsTypeA {
-		srcip, _ := getPacketIP4Addrs(pkt)
+		srcip, _ := getPacketIPAddrs(pkt)
 		pinfo := getEmptyPInfo()
 		if !isNSTrusted(srcip) {
 			pinfo, _  = findProcessForPacket(pkt, true, procsnitch.MATCH_LOOSEST)
@@ -145,6 +145,8 @@ func (dc *dnsCache) processRecordA(name string, answers []dnsRR, pid int) {
 			if !FirewallConfig.LogRedact {
 				log.Infof("Adding %s: %s", name, ip)
 			}
+		case *dnsRR_AAAA:
+			log.Warning("AAAA record read from DNS; not supported.")
 		case *dnsRR_CNAME:
 			// Not that exotic; just ignore it
 		default:

sgfw/icons.go

@@ -68,7 +68,10 @@ func loadDesktopFile(path string) {
 			inDE = false
 		}
 		if inDE && strings.HasPrefix(line, "Exec=") {
-			exec = strings.Fields(line[5:])[0]
+			fields := strings.Fields(line[5:])
+			if len(fields) > 0 {
+				exec = fields[0]
+			}
 		}
 		if inDE && strings.HasPrefix(line, "Icon=") {
 			icon = line[5:]

sgfw/ipc.go

@@ -7,7 +7,6 @@ import (
 	"bufio"
 	"strings"
 	"strconv"
-	"encoding/binary"
 )
 
 const ReceiverSocketPath = "/tmp/fwoz.sock"
@@ -120,8 +119,6 @@ func ReceiverLoop(fw *Firewall, c net.Conn) {
 			c.Write([]byte(banner))
 
 			for r := 0; r < len(rl); r++ {
-				ip := make([]byte, 4)
-		                binary.BigEndian.PutUint32(ip, rl[r].addr)
 				hostname := ""
 
 				if rl[r].hostname != "" {
@@ -134,7 +131,7 @@ func ReceiverLoop(fw *Firewall, c net.Conn) {
 					portstr = "*"
 				}
 
-				ruledesc := fmt.Sprintf("id %v, %v | %v, src:%v -> %v%v: %v\n", rl[r].id, RuleModeString[rl[r].mode], RuleActionString[rl[r].rtype], rl[r].saddr, net.IP(ip), hostname, portstr)
+				ruledesc := fmt.Sprintf("id %v, %v | %v, src:%v -> %v%v: %v\n", rl[r].id, RuleModeString[rl[r].mode], RuleActionString[rl[r].rtype], rl[r].saddr, rl[r].addr, hostname, portstr)
 				c.Write([]byte(ruledesc))
 			}
 

sgfw/policy.go

@@ -93,21 +93,13 @@ func (pp *pendingPkt) hostname() string {
 }
 
 func (pp *pendingPkt) src() net.IP {
-	src, _ := getPacketIP4Addrs(pp.pkt)
+	src, _ := getPacketIPAddrs(pp.pkt)
 	return src
 }
 
 func (pp *pendingPkt) dst() net.IP {
-	_, dst := getPacketIP4Addrs(pp.pkt)
+	_, dst := getPacketIPAddrs(pp.pkt)
 	return dst
-/*	dst := pp.pkt.Packet.NetworkLayer().NetworkFlow().Dst()
-
-	if dst.EndpointType() != layers.EndpointIPv4 {
-		return nil
-	}
-
-	return dst.Raw() */
-//	pp.pkt.NetworkLayer().Layer
 }
 
 func getNFQProto(pkt *nfqueue.NFQPacket) string {
@@ -368,7 +360,7 @@ func (p *Policy) hasPersistentRules() bool {
 func printPacket(pkt *nfqueue.NFQPacket, hostname string, pinfo *procsnitch.Info) string {
 	proto := "???"
 	SrcPort, DstPort := uint16(0), uint16(0)
-	SrcIp, DstIp := getPacketIP4Addrs(pkt)
+	SrcIp, DstIp := getPacketIPAddrs(pkt)
 	code := 0
 	codestr := ""
 
@@ -418,7 +410,7 @@ func (fw *Firewall) filterPacket(pkt *nfqueue.NFQPacket) {
 		}
 
 	}
-	_, dstip := getPacketIP4Addrs(pkt)
+	_, dstip := getPacketIPAddrs(pkt)
 /*	_, dstp := getPacketPorts(pkt)
 	fwo := matchAgainstOzRules(srcip, dstip, dstp)
 	log.Notice("XXX: Attempting [2] to filter packet on rules -> ", fwo)
@@ -558,14 +550,14 @@ func getRealRoot(pathname string, pid int) string {
 }
 
 func findProcessForPacket(pkt *nfqueue.NFQPacket, reverse bool, strictness int) (*procsnitch.Info, string) {
-	srcip, dstip := getPacketIP4Addrs(pkt)
+	srcip, dstip := getPacketIPAddrs(pkt)
 	srcp, dstp := getPacketPorts(pkt)
 	proto := ""
 	optstr := ""
 	icode := -1
 
 	if reverse {
-		dstip, srcip = getPacketIP4Addrs(pkt)
+		dstip, srcip = getPacketIPAddrs(pkt)
 		dstp, srcp = getPacketPorts(pkt)
 	}
 
@@ -576,6 +568,9 @@ func findProcessForPacket(pkt *nfqueue.NFQPacket, reverse bool, strictness int)
 	} else if pkt.Packet.Layer(layers.LayerTypeICMPv4) != nil {
 		proto = "icmp"
 		icode, _ = getpacketICMPCode(pkt)
+	} else if pkt.Packet.Layer(layers.LayerTypeICMPv6) != nil {
+		proto = "icmp"
+		icode, _ = getpacketICMPCode(pkt)
 	}
 
 	if proto == "" {
@@ -656,7 +651,7 @@ func findProcessForPacket(pkt *nfqueue.NFQPacket, reverse bool, strictness int)
 }
 
 func basicAllowPacket(pkt *nfqueue.NFQPacket) bool {
-	srcip, dstip := getPacketIP4Addrs(pkt)
+	srcip, dstip := getPacketIPAddrs(pkt)
 	if pkt.Packet.Layer(layers.LayerTypeUDP) != nil {
 		_, dport := getPacketUDPPorts(pkt)
 		if dport == 53 {
@@ -674,15 +669,29 @@ func basicAllowPacket(pkt *nfqueue.NFQPacket) bool {
 		 pkt.Packet.Layer(layers.LayerTypeICMPv4) == nil)
 }
 
-func getPacketIP4Addrs(pkt *nfqueue.NFQPacket) (net.IP, net.IP) {
+func getPacketIPAddrs(pkt *nfqueue.NFQPacket) (net.IP, net.IP) {
+	ipv4 := true
 	ipLayer := pkt.Packet.Layer(layers.LayerTypeIPv4)
 
 	if ipLayer == nil {
-		return net.IP{0,0,0,0}, net.IP{0,0,0,0}
+		ipv4 = false
+		ipLayer = pkt.Packet.Layer(layers.LayerTypeIPv6)
+	}
+
+	if ipLayer == nil {
+		if ipv4 {
+			return net.IP{0,0,0,0}, net.IP{0,0,0,0}
+		}
+		return net.IP{}, net.IP{}
+	}
+
+	if !ipv4 {
+		ip6, _ := ipLayer.(*layers.IPv6)
+		return ip6.SrcIP, ip6.DstIP
 	}
 
-	ip, _ := ipLayer.(*layers.IPv4)
-	return ip.SrcIP, ip.DstIP
+	ip4, _ := ipLayer.(*layers.IPv4)
+	return ip4.SrcIP, ip4.DstIP
 }
 
 func getpacketICMPCode(pkt *nfqueue.NFQPacket) (int, string) {

sgfw/rules.go

@@ -9,7 +9,6 @@ import (
 	"path"
 	"strconv"
 	"strings"
-	"unicode"
 	"regexp"
 
 	nfqueue "github.com/subgraph/go-nfnetlink/nfqueue"
@@ -18,7 +17,9 @@ import (
 )
 
 const matchAny = 0
-const noAddress = uint32(0xffffffff)
+//const noAddress = uint32(0xffffffff)
+var anyAddress net.IP = net.IP{0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,}
+var noAddress net.IP = net.IP{0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff}
 
 type Rule struct {
 	id       uint
@@ -28,7 +29,7 @@ type Rule struct {
 	proto    string
 	hostname string
 	network  *net.IPNet
-	addr     uint32
+	addr     net.IP
 	saddr    net.IP
 	port     uint16
 	uid      int
@@ -66,10 +67,11 @@ func (r *Rule) AddrString(redact bool) string {
 		addr = r.hostname
 	} else if r.network != nil {
 		addr = r.network.String()
-	} else if r.addr != matchAny && r.addr != noAddress {
-		bs := make([]byte, 4)
-		binary.BigEndian.PutUint32(bs, r.addr)
-		addr = fmt.Sprintf("%d.%d.%d.%d", bs[0], bs[1], bs[2], bs[3])
+	} else if !addrMatchesAny(r.addr) && !addrMatchesNone(r.addr) {
+//		bs := make([]byte, 4)
+//		binary.BigEndian.PutUint32(bs, r.addr)
+//		addr = fmt.Sprintf("%d.%d.%d.%d", bs[0], bs[1], bs[2], bs[3])
+		addr = r.addr.String()
 	}
 
 	if r.port != matchAny || r.proto == "icmp" {
@@ -99,13 +101,11 @@ func (r *Rule) match(src net.IP, dst net.IP, dstPort uint16, hostname string, pr
 		return false
 	}
 
-xip := make(net.IP, 4)
-binary.BigEndian.PutUint32(xip, r.addr)
-log.Notice("comparison: ", hostname, " / ", dst, " : ", dstPort, " -> ", xip, " / ", r.hostname, " : ", r.port)
+log.Notice("comparison: ", hostname, " / ", dst, " : ", dstPort, " -> ", r.addr, " / ", r.hostname, " : ", r.port)
 	if r.port != matchAny && r.port != dstPort {
 		return false
 	}
-	if r.addr == matchAny {
+	if addrMatchesAny(r.addr) {
 		return true
 	}
 	if r.hostname != "" {
@@ -126,15 +126,15 @@ log.Notice("comparison: ", hostname, " / ", dst, " : ", dstPort, " -> ", xip, "
 	}
 	if proto == "icmp" {
 		fmt.Printf("network = %v, src = %v, r.addr = %x, src to4 = %x\n", r.network, src, r.addr, binary.BigEndian.Uint32(src.To4()))
-		if  (r.network != nil && r.network.Contains(src)) || (r.addr == binary.BigEndian.Uint32(src.To4())) {
+		if  (r.network != nil && r.network.Contains(src)) || (r.addr.Equal(src)) {
 			return true
 		}
 	}
-	return r.addr == binary.BigEndian.Uint32(dst.To4())
+	return r.addr.Equal(dst)
 }
 
 func (rl *RuleList) filterPacket(p *nfqueue.NFQPacket, pinfo *procsnitch.Info, srcip net.IP, hostname, optstr string) FilterResult {
-	_, dstip := getPacketIP4Addrs(p)
+	_, dstip := getPacketIPAddrs(p)
 	_, dstp := getPacketPorts(p)
 	return rl.filter(p, srcip, dstip, dstp, hostname, pinfo, optstr)
 }
@@ -162,7 +162,7 @@ log.Notice("+ MATCH SUCCEEDED")
 			}
 			srcStr := STR_UNKNOWN
 			if pkt != nil {
-				srcip, _ := getPacketIP4Addrs(pkt)
+				srcip, _ := getPacketIPAddrs(pkt)
 				srcp, _ := getPacketPorts(pkt)
 				srcStr = fmt.Sprintf("%s:%d", srcip, srcp)
 			}
@@ -272,30 +272,31 @@ func (r *Rule) parseVerb(v string) bool {
 
 func (r *Rule) parseTarget(t string) bool {
 	addrPort := strings.Split(t, ":")
-	if len(addrPort) != 2 && len(addrPort) != 3 {
+	if len(addrPort) < 2 {
 		return false
 	}
 	sind := 0
-	if len(addrPort) == 3 {
-		if addrPort[0] != "udp" && addrPort[0] != "icmp" && addrPort[0] != "tcp" {
-			return false
-		}
+	lind := len(addrPort)-1
+	if addrPort[0] == "udp" || addrPort[0] == "icmp" || addrPort[0] == "tcp" {
 		r.proto = addrPort[0]
 		sind++
 	} else {
 		r.proto = "tcp"
 	}
 
-	return r.parseAddr(addrPort[sind]) && r.parsePort(addrPort[sind+1])
+	newAddr := strings.Join(addrPort[sind:lind], ":")
+	return r.parseAddr(newAddr) && r.parsePort(addrPort[lind])
+//	return r.parseAddr(addrPort[sind]) && r.parsePort(addrPort[sind+1])
 }
 
 func (r *Rule) parseAddr(a string) bool {
 	if a == "*" {
 		r.hostname = ""
-		r.addr = matchAny
+		r.addr = anyAddress
 		return true
 	}
-	if strings.IndexFunc(a, unicode.IsLetter) != -1 {
+//	if strings.IndexFunc(a, unicode.IsLetter) != -1 {
+	if net.ParseIP(a) == nil {
 		r.hostname = a
 		return true
 	}
@@ -310,7 +311,7 @@ func (r *Rule) parseAddr(a string) bool {
 	} else {
 		r.network = ipnet
 	}
-	r.addr = binary.BigEndian.Uint32(ip.To4())
+	r.addr = ip
 	return true
 }
 
@@ -445,3 +446,23 @@ func processRuleLine(policy *Policy, line string) {
 		return
 	}
 }
+
+func addrMatchesAny(addr net.IP) bool {
+	any := anyAddress
+
+	if addr.To4() != nil {
+		any = net.IP{0,0,0,0}
+	}
+
+	return any.Equal(addr)
+}
+
+func addrMatchesNone(addr net.IP) bool {
+	none := noAddress
+
+	if addr.To4() != nil {
+		none = net.IP{0xff,0xff,0xff,0xff}
+	}
+
+	return none.Equal(addr)
+}

sgfw/sgfw.go

@@ -16,6 +16,8 @@ import (
 	nfqueue "github.com/subgraph/go-nfnetlink/nfqueue"
 //	"github.com/subgraph/go-nfnetlink"
 	"github.com/subgraph/go-procsnitch"
+	"github.com/google/gopacket"
+	"github.com/google/gopacket/layers"
 )
 
 var dbusp *dbusObjectP = nil
@@ -108,6 +110,22 @@ func (fw *Firewall) runFilter() {
 	go func() {
 		for p := range ps {
 			if fw.isEnabled() {
+				ipLayer := p.Packet.Layer(layers.LayerTypeIPv4)
+				if ipLayer == nil {
+					continue
+				}
+
+				ip, _ := ipLayer.(*layers.IPv4)
+				if ip == nil {
+					continue
+				}
+
+				if ip.Version == 6 {
+					ip6p := gopacket.NewPacket(ip.LayerContents(), layers.LayerTypeIPv6, gopacket.Default)
+					p.Packet = ip6p
+
+				}
+
 				fw.filterPacket(p)
 			} else {
 				p.Accept()

vendor/github.com/subgraph/go-procsnitch/proc.go

@@ -2,6 +2,7 @@ package procsnitch
 
 import (
 	"encoding/hex"
+	"encoding/binary"
 	"errors"
 	"fmt"
 	"github.com/op/go-logging"
@@ -9,9 +10,11 @@ import (
 	"net"
 	"strconv"
 	"strings"
+	"unsafe"
 )
 
 var log = logging.MustGetLogger("go-procsockets")
+var isLittleEndian = -1
 
 // SetLogger allows setting a custom go-logging instance
 func SetLogger(logger *logging.Logger) {
@@ -157,11 +160,32 @@ func ParseIP(ip string) (net.IP, error) {
 	}
 	// Reverse byte order -- /proc/net/tcp etc. is little-endian
 	// TODO: Does this vary by architecture?
-	for i, j := 0, len(dst)-1; i < j; i, j = i+1, j-1 {
-		dst[i], dst[j] = dst[j], dst[i]
+	if isLittleEndian == -1 {
+		setEndian()
 	}
-	result = net.IP(dst)
-	return result, nil
+
+	if len(dst) != 4 && len(dst) != 16 {
+		return result, errors.New("Unsupported address type (not IPv4 or IPv16)")
+	}
+
+	if isLittleEndian > 0 {
+		for i := 0; i < len(dst) / 4; i++ {
+			start, end := i*4, (i+1)*4
+			word := dst[start:end]
+			lval := binary.LittleEndian.Uint32(word)
+			binary.BigEndian.PutUint32(dst[start:], lval)
+		}
+	}
+
+/*		if len(dst) == 16 {
+			dst2 := []byte{dst[3], dst[2], dst[1], dst[0], dst[7], dst[6], dst[5], dst[4], dst[11], dst[10], dst[9], dst[8], dst[15], dst[14], dst[13], dst[12]}
+			return net.IP(dst2), nil
+		}
+		for i, j := 0, len(dst)-1; i < j; i, j = i+1, j-1 {
+			dst[i], dst[j] = dst[j], dst[i]
+		} */
+
+	return net.IP(dst), nil
 }
 
 // ParsePort parses a base16 port represented as a string to a uint16
@@ -285,3 +309,15 @@ func stripLabel(s string) string {
 	}
 	return s[idx+1:]
 }
+
+// stolen from github.com/virtao/GoEndian
+const INT_SIZE int = int(unsafe.Sizeof(0))
+func setEndian() {
+	var i int = 0x1
+	bs := (*[INT_SIZE]byte)(unsafe.Pointer(&i))
+	if bs[0] == 0 {
+		isLittleEndian = 0
+	} else {
+		isLittleEndian = 1
+	}
+}

vendor/github.com/subgraph/go-procsnitch/socket.go

@@ -85,52 +85,61 @@ func (ss *socketStatus) String() string {
 }
 
 func findICMPSocketAll(srcAddr net.IP, dstAddr net.IP, code int, custdata []string) *socketStatus {
+	proto := "icmp"
+	if srcAddr.To4() == nil {
+		proto += "6"
+	}
+
 	if custdata == nil {
-		return findSocket("icmp", func(ss socketStatus) bool {
+		return findSocket(proto, func(ss socketStatus) bool {
 			return ss.remote.ip.Equal(dstAddr) && ss.local.ip.Equal(srcAddr)
 		})
 	}
 
-	return findSocketCustom("icmp", custdata, func(ss socketStatus) bool {
+	return findSocketCustom(proto, custdata, func(ss socketStatus) bool {
 		return ss.remote.ip.Equal(dstAddr) && ss.local.ip.Equal(srcAddr)
 	})
 }
 
 func findUDPSocketAll(srcAddr net.IP, srcPort uint16, dstAddr net.IP, dstPort uint16, custdata []string, strictness int) *socketStatus {
-	wildcard := net.IP{0,0,0,0}
+	proto := "udp"
+
+	if srcAddr.To4() == nil {
+		proto += "6"
+	}
 
 	if custdata == nil {
 		if strictness == MATCH_STRICT {
-			return findSocket("udp", func(ss socketStatus) bool {
+			return findSocket(proto, func(ss socketStatus) bool {
 				return ss.remote.ip.Equal(dstAddr) && ss.local.port == srcPort && ss.local.ip.Equal(srcAddr)
 			})
 		} else if strictness == MATCH_LOOSE {
-			return findSocket("udp", func(ss socketStatus) bool {
-				return (ss.remote.ip.Equal(dstAddr) || ss.remote.ip.Equal(wildcard)) && ss.local.port == srcPort && ss.local.ip.Equal(srcAddr) ||
-					(ss.local.ip.Equal(dstAddr) || ss.local.ip.Equal(wildcard)) && ss.remote.port == srcPort && ss.remote.ip.Equal(srcAddr)
+			return findSocket(proto, func(ss socketStatus) bool {
+				return (ss.remote.ip.Equal(dstAddr) || addrMatchesAny(ss.remote.ip)) && ss.local.port == srcPort && ss.local.ip.Equal(srcAddr) ||
+					(ss.local.ip.Equal(dstAddr) || addrMatchesAny(ss.local.ip)) && ss.remote.port == srcPort && ss.remote.ip.Equal(srcAddr)
 			})
 		}
-		return findSocket("udp", func(ss socketStatus) bool {
-			return (ss.remote.ip.Equal(dstAddr) || ss.remote.ip.Equal(wildcard)) && ss.local.port == srcPort && (ss.local.ip.Equal(srcAddr) || ss.local.ip.Equal(wildcard)) ||
-				(ss.local.ip.Equal(dstAddr) || ss.local.ip.Equal(wildcard)) && ss.remote.port == srcPort && (ss.remote.ip.Equal(srcAddr) || ss.remote.ip.Equal(srcAddr))
+		return findSocket(proto, func(ss socketStatus) bool {
+			return (ss.remote.ip.Equal(dstAddr) || addrMatchesAny(ss.remote.ip)) && ss.local.port == srcPort && (ss.local.ip.Equal(srcAddr) || addrMatchesAny(ss.local.ip)) ||
+				(ss.local.ip.Equal(dstAddr) || addrMatchesAny(ss.local.ip)) && ss.remote.port == srcPort && (ss.remote.ip.Equal(srcAddr) || ss.remote.ip.Equal(srcAddr))
 		})
 
 	}
 
 	if strictness == MATCH_STRICT {
-		return findSocketCustom("udp", custdata, func(ss socketStatus) bool {
+		return findSocketCustom(proto, custdata, func(ss socketStatus) bool {
 			return ss.remote.ip.Equal(dstAddr) && ss.local.port == srcPort && ss.local.ip.Equal(srcAddr)
 		})
 	} else if strictness == MATCH_LOOSE {
-		return findSocketCustom("udp", custdata, func(ss socketStatus) bool {
-			return (ss.remote.ip.Equal(dstAddr) || ss.remote.ip.Equal(wildcard)) && ss.local.port == srcPort && ss.local.ip.Equal(srcAddr) ||
-				(ss.local.ip.Equal(dstAddr) || ss.local.ip.Equal(wildcard)) && ss.remote.port == srcPort && ss.remote.ip.Equal(srcAddr)
+		return findSocketCustom(proto, custdata, func(ss socketStatus) bool {
+			return (ss.remote.ip.Equal(dstAddr) || addrMatchesAny(ss.remote.ip)) && ss.local.port == srcPort && ss.local.ip.Equal(srcAddr) ||
+				(ss.local.ip.Equal(dstAddr) || addrMatchesAny(ss.local.ip)) && ss.remote.port == srcPort && ss.remote.ip.Equal(srcAddr)
 		})
 	}
 
-	return findSocketCustom("udp", custdata, func(ss socketStatus) bool {
-		return (ss.remote.ip.Equal(dstAddr) || ss.remote.ip.Equal(wildcard)) && ss.local.port == srcPort && (ss.local.ip.Equal(srcAddr) || ss.local.ip.Equal(wildcard)) ||
-			(ss.local.ip.Equal(dstAddr) || ss.local.ip.Equal(wildcard)) && ss.remote.port == srcPort && (ss.remote.ip.Equal(srcAddr) || ss.remote.ip.Equal(srcAddr))
+	return findSocketCustom(proto, custdata, func(ss socketStatus) bool {
+		return (ss.remote.ip.Equal(dstAddr) || addrMatchesAny(ss.remote.ip)) && ss.local.port == srcPort && (ss.local.ip.Equal(srcAddr) || addrMatchesAny(ss.local.ip)) ||
+			(ss.local.ip.Equal(dstAddr) || addrMatchesAny(ss.local.ip)) && ss.remote.port == srcPort && (ss.remote.ip.Equal(srcAddr) || ss.remote.ip.Equal(srcAddr))
 	})
 }
 
@@ -141,19 +150,29 @@ func findUDPSocket(srcPort uint16) *socketStatus {
 }
 
 func findTCPSocket(srcPort uint16, dstAddr net.IP, dstPort uint16) *socketStatus {
-	return findSocket("tcp", func(ss socketStatus) bool {
+	proto := "tcp"
+	if dstAddr.To4() == nil {
+		proto += "6"
+	}
+
+	return findSocket(proto, func(ss socketStatus) bool {
 		return ss.remote.port == dstPort && ss.remote.ip.Equal(dstAddr) && ss.local.port == srcPort
 	})
 }
 
 func findTCPSocketAll(srcAddr net.IP, srcPort uint16, dstAddr net.IP, dstPort uint16, custdata []string) *socketStatus {
+	proto := "tcp"
+	if srcAddr.To4() == nil {
+		proto += "6"
+	}
+
 	if custdata == nil {
-		return findSocket("tcp", func(ss socketStatus) bool {
+		return findSocket(proto, func(ss socketStatus) bool {
 			return ss.remote.port == dstPort && ss.remote.ip.Equal(dstAddr) && ss.local.port == srcPort && ss.local.ip.Equal(srcAddr)
 		})
 	}
 
-	return findSocketCustom("tcp", custdata, func(ss socketStatus) bool {
+	return findSocketCustom(proto, custdata, func(ss socketStatus) bool {
 		return ss.remote.port == dstPort && ss.remote.ip.Equal(dstAddr) && ss.local.port == srcPort && ss.local.ip.Equal(srcAddr)
 	})
 }
@@ -298,3 +317,13 @@ func getSocketLines(proto string) []string {
 	}
 	return lines
 }
+
+func addrMatchesAny(addr net.IP) bool {
+	wildcard := net.IP{0,0,0,0}
+
+	if addr.To4() == nil {
+		wildcard = net.IP{0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}
+	}
+
+        return wildcard.Equal(addr)
+}