Merge pull request #113 from slackhq/fw-ca

Fixes the issues with caSha and caName
This commit is contained in:
Nathan Brown 2019-12-19 09:06:50 -08:00 committed by GitHub
commit e465b13045
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
3 changed files with 254 additions and 99 deletions

View File

@ -141,7 +141,7 @@ firewall:
# The firewall is default deny. There is no way to write a deny rule.
# Rules are comprised of a protocol, port, and one or more of host, group, or CIDR
# Logical evaluation is roughly: port AND proto AND ca_sha AND ca_name AND (host OR group OR groups OR cidr)
# Logical evaluation is roughly: port AND proto AND (ca_sha OR ca_name) AND (host OR group OR groups OR cidr)
# - port: Takes `0` or `any` as any, a single number `80`, a range `200-901`, or `fragment` to match second and further fragments of fragmented packets (since there is no port available).
# code: same as port but makes more sense when talking about ICMP, TODO: this is not currently implemented in a way that works, use `any`
# proto: `any`, `tcp`, `udp`, or `icmp`

View File

@ -83,19 +83,23 @@ func newFirewallTable() *FirewallTable {
}
}
type FirewallCA struct {
Any *FirewallRule
CANames map[string]*FirewallRule
CAShas map[string]*FirewallRule
}
type FirewallRule struct {
// Any makes Hosts, Groups, and CIDR irrelevant. CAName and CASha still need to be checked
// Any makes Hosts, Groups, and CIDR irrelevant
Any bool
Hosts map[string]struct{}
Groups [][]string
CIDR *CIDRTree
CANames map[string]struct{}
CAShas map[string]struct{}
}
// Even though ports are uint16, int32 maps are faster for lookup
// Plus we can use `-1` for fragment rules
type firewallPort map[int32]*FirewallRule
type firewallPort map[int32]*FirewallCA
type FirewallPacket struct {
LocalIP uint32
@ -182,9 +186,9 @@ func NewFirewall(tcpTimeout, UDPTimeout, defaultTimeout time.Duration, c *cert.N
func NewFirewallFromConfig(nc *cert.NebulaCertificate, c *Config) (*Firewall, error) {
fw := NewFirewall(
c.GetDuration("firewall.conntrack.tcp_timeout", time.Duration(time.Minute*12)),
c.GetDuration("firewall.conntrack.udp_timeout", time.Duration(time.Minute*3)),
c.GetDuration("firewall.conntrack.default_timeout", time.Duration(time.Minute*10)),
c.GetDuration("firewall.conntrack.tcp_timeout", time.Minute*12),
c.GetDuration("firewall.conntrack.udp_timeout", time.Minute*3),
c.GetDuration("firewall.conntrack.default_timeout", time.Minute*10),
nc,
//TODO: max_connections
)
@ -499,12 +503,9 @@ func (fp firewallPort) addRule(startPort int32, endPort int32, groups []string,
for i := startPort; i <= endPort; i++ {
if _, ok := fp[i]; !ok {
fp[i] = &FirewallRule{
Groups: make([][]string, 0),
Hosts: make(map[string]struct{}),
CIDR: NewCIDRTree(),
CANames: make(map[string]struct{}),
CAShas: make(map[string]struct{}),
fp[i] = &FirewallCA{
CANames: make(map[string]*FirewallRule),
CAShas: make(map[string]*FirewallRule),
}
}
@ -539,15 +540,70 @@ func (fp firewallPort) match(p FirewallPacket, incoming bool, c *cert.NebulaCert
return fp[fwPortAny].match(p, c, caPool)
}
func (fr *FirewallRule) addRule(groups []string, host string, ip *net.IPNet, caName string, caSha string) error {
if caName != "" {
fr.CANames[caName] = struct{}{}
func (fc *FirewallCA) addRule(groups []string, host string, ip *net.IPNet, caName, caSha string) error {
fr := func() *FirewallRule {
return &FirewallRule{
Hosts: make(map[string]struct{}),
Groups: make([][]string, 0),
CIDR: NewCIDRTree(),
}
}
if caSha == "" && caName == "" {
if fc.Any == nil {
fc.Any = fr()
}
return fc.Any.addRule(groups, host, ip)
}
if caSha != "" {
fr.CAShas[caSha] = struct{}{}
if _, ok := fc.CAShas[caSha]; !ok {
fc.CAShas[caSha] = fr()
}
err := fc.CAShas[caSha].addRule(groups, host, ip)
if err != nil {
return err
}
}
if caName != "" {
if _, ok := fc.CANames[caName]; !ok {
fc.CANames[caName] = fr()
}
err := fc.CANames[caName].addRule(groups, host, ip)
if err != nil {
return err
}
}
return nil
}
func (fc *FirewallCA) match(p FirewallPacket, c *cert.NebulaCertificate, caPool *cert.NebulaCAPool) bool {
if fc == nil {
return false
}
if fc.Any.match(p, c) {
return true
}
if t, ok := fc.CAShas[c.Details.Issuer]; ok {
if t.match(p, c) {
return true
}
}
s, err := caPool.GetCAForCert(c)
if err != nil {
return false
}
return fc.CANames[s.Details.Name].match(p, c)
}
func (fr *FirewallRule) addRule(groups []string, host string, ip *net.IPNet) error {
if fr.Any {
return nil
}
@ -576,6 +632,10 @@ func (fr *FirewallRule) addRule(groups []string, host string, ip *net.IPNet, caN
}
func (fr *FirewallRule) isAny(groups []string, host string, ip *net.IPNet) bool {
if len(groups) == 0 && host == "" && ip == nil {
return true
}
for _, group := range groups {
if group == "any" {
return true
@ -593,28 +653,11 @@ func (fr *FirewallRule) isAny(groups []string, host string, ip *net.IPNet) bool
return false
}
func (fr *FirewallRule) match(p FirewallPacket, c *cert.NebulaCertificate, caPool *cert.NebulaCAPool) bool {
func (fr *FirewallRule) match(p FirewallPacket, c *cert.NebulaCertificate) bool {
if fr == nil {
return false
}
// CASha and CAName always need to be checked
if len(fr.CAShas) > 0 {
if _, ok := fr.CAShas[c.Details.Issuer]; !ok {
return false
}
}
if len(fr.CANames) > 0 {
s, err := caPool.GetCAForCert(c)
if err != nil {
return false
}
if _, ok := fr.CANames[s.Details.Name]; !ok {
return false
}
}
// Shortcut path for if groups, hosts, or cidr contained an `any`
if fr.Any {
return true
@ -773,7 +816,7 @@ func setTCPRTTTracking(c *conn, p []byte) {
ihl := int(p[0]&0x0f) << 2
// Don't track FIN packets
if uint8(p[ihl+13])&tcpFIN != 0 {
if p[ihl+13]&tcpFIN != 0 {
return
}
@ -787,7 +830,7 @@ func (f *Firewall) checkTCPRTT(c *conn, p []byte) bool {
}
ihl := int(p[0]&0x0f) << 2
if uint8(p[ihl+13])&tcpACK == 0 {
if p[ihl+13]&tcpACK == 0 {
return false
}

View File

@ -51,6 +51,11 @@ func TestNewFirewall(t *testing.T) {
}
func TestFirewall_AddRule(t *testing.T) {
ob := &bytes.Buffer{}
out := l.Out
l.SetOutput(ob)
defer l.SetOutput(out)
c := &cert.NebulaCertificate{}
fw := NewFirewall(time.Second, time.Minute, time.Hour, c)
assert.NotNil(t, fw.InRules)
@ -59,39 +64,38 @@ func TestFirewall_AddRule(t *testing.T) {
_, ti, _ := net.ParseCIDR("1.2.3.4/32")
assert.Nil(t, fw.AddRule(true, fwProtoTCP, 1, 1, []string{}, "", nil, "", ""))
// Make sure an empty rule creates structure but doesn't allow anything to flow
//TODO: ideally an empty rule would return an error
assert.False(t, fw.InRules.TCP[1].Any)
assert.Empty(t, fw.InRules.TCP[1].Groups)
assert.Empty(t, fw.InRules.TCP[1].Hosts)
assert.Nil(t, fw.InRules.TCP[1].CIDR.root.left)
assert.Nil(t, fw.InRules.TCP[1].CIDR.root.right)
assert.Nil(t, fw.InRules.TCP[1].CIDR.root.value)
// An empty rule is any
assert.True(t, fw.InRules.TCP[1].Any.Any)
assert.Empty(t, fw.InRules.TCP[1].Any.Groups)
assert.Empty(t, fw.InRules.TCP[1].Any.Hosts)
assert.Nil(t, fw.InRules.TCP[1].Any.CIDR.root.left)
assert.Nil(t, fw.InRules.TCP[1].Any.CIDR.root.right)
assert.Nil(t, fw.InRules.TCP[1].Any.CIDR.root.value)
fw = NewFirewall(time.Second, time.Minute, time.Hour, c)
assert.Nil(t, fw.AddRule(true, fwProtoUDP, 1, 1, []string{"g1"}, "", nil, "", ""))
assert.False(t, fw.InRules.UDP[1].Any)
assert.Contains(t, fw.InRules.UDP[1].Groups[0], "g1")
assert.Empty(t, fw.InRules.UDP[1].Hosts)
assert.Nil(t, fw.InRules.UDP[1].CIDR.root.left)
assert.Nil(t, fw.InRules.UDP[1].CIDR.root.right)
assert.Nil(t, fw.InRules.UDP[1].CIDR.root.value)
assert.False(t, fw.InRules.UDP[1].Any.Any)
assert.Contains(t, fw.InRules.UDP[1].Any.Groups[0], "g1")
assert.Empty(t, fw.InRules.UDP[1].Any.Hosts)
assert.Nil(t, fw.InRules.UDP[1].Any.CIDR.root.left)
assert.Nil(t, fw.InRules.UDP[1].Any.CIDR.root.right)
assert.Nil(t, fw.InRules.UDP[1].Any.CIDR.root.value)
fw = NewFirewall(time.Second, time.Minute, time.Hour, c)
assert.Nil(t, fw.AddRule(true, fwProtoICMP, 1, 1, []string{}, "h1", nil, "", ""))
assert.False(t, fw.InRules.ICMP[1].Any)
assert.Empty(t, fw.InRules.ICMP[1].Groups)
assert.Contains(t, fw.InRules.ICMP[1].Hosts, "h1")
assert.Nil(t, fw.InRules.ICMP[1].CIDR.root.left)
assert.Nil(t, fw.InRules.ICMP[1].CIDR.root.right)
assert.Nil(t, fw.InRules.ICMP[1].CIDR.root.value)
assert.False(t, fw.InRules.ICMP[1].Any.Any)
assert.Empty(t, fw.InRules.ICMP[1].Any.Groups)
assert.Contains(t, fw.InRules.ICMP[1].Any.Hosts, "h1")
assert.Nil(t, fw.InRules.ICMP[1].Any.CIDR.root.left)
assert.Nil(t, fw.InRules.ICMP[1].Any.CIDR.root.right)
assert.Nil(t, fw.InRules.ICMP[1].Any.CIDR.root.value)
fw = NewFirewall(time.Second, time.Minute, time.Hour, c)
assert.Nil(t, fw.AddRule(false, fwProtoAny, 1, 1, []string{}, "", ti, "", ""))
assert.False(t, fw.OutRules.AnyProto[1].Any)
assert.Empty(t, fw.OutRules.AnyProto[1].Groups)
assert.Empty(t, fw.OutRules.AnyProto[1].Hosts)
assert.NotNil(t, fw.OutRules.AnyProto[1].CIDR.Match(ip2int(ti.IP)))
assert.False(t, fw.OutRules.AnyProto[1].Any.Any)
assert.Empty(t, fw.OutRules.AnyProto[1].Any.Groups)
assert.Empty(t, fw.OutRules.AnyProto[1].Any.Hosts)
assert.NotNil(t, fw.OutRules.AnyProto[1].Any.CIDR.Match(ip2int(ti.IP)))
fw = NewFirewall(time.Second, time.Minute, time.Hour, c)
assert.Nil(t, fw.AddRule(true, fwProtoUDP, 1, 1, []string{"g1"}, "", nil, "ca-name", ""))
@ -104,28 +108,29 @@ func TestFirewall_AddRule(t *testing.T) {
// Set any and clear fields
fw = NewFirewall(time.Second, time.Minute, time.Hour, c)
assert.Nil(t, fw.AddRule(false, fwProtoAny, 0, 0, []string{"g1", "g2"}, "h1", ti, "", ""))
assert.Equal(t, []string{"g1", "g2"}, fw.OutRules.AnyProto[0].Groups[0])
assert.Contains(t, fw.OutRules.AnyProto[0].Hosts, "h1")
assert.NotNil(t, fw.OutRules.AnyProto[0].CIDR.Match(ip2int(ti.IP)))
assert.Equal(t, []string{"g1", "g2"}, fw.OutRules.AnyProto[0].Any.Groups[0])
assert.Contains(t, fw.OutRules.AnyProto[0].Any.Hosts, "h1")
assert.NotNil(t, fw.OutRules.AnyProto[0].Any.CIDR.Match(ip2int(ti.IP)))
// run twice just to make sure
//TODO: these ANY rules should clear the CA firewall portion
assert.Nil(t, fw.AddRule(false, fwProtoAny, 0, 0, []string{"any"}, "", nil, "", ""))
assert.Nil(t, fw.AddRule(false, fwProtoAny, 0, 0, []string{}, "any", nil, "", ""))
assert.True(t, fw.OutRules.AnyProto[0].Any)
assert.Empty(t, fw.OutRules.AnyProto[0].Groups)
assert.Empty(t, fw.OutRules.AnyProto[0].Hosts)
assert.Nil(t, fw.OutRules.AnyProto[0].CIDR.root.left)
assert.Nil(t, fw.OutRules.AnyProto[0].CIDR.root.right)
assert.Nil(t, fw.OutRules.AnyProto[0].CIDR.root.value)
assert.True(t, fw.OutRules.AnyProto[0].Any.Any)
assert.Empty(t, fw.OutRules.AnyProto[0].Any.Groups)
assert.Empty(t, fw.OutRules.AnyProto[0].Any.Hosts)
assert.Nil(t, fw.OutRules.AnyProto[0].Any.CIDR.root.left)
assert.Nil(t, fw.OutRules.AnyProto[0].Any.CIDR.root.right)
assert.Nil(t, fw.OutRules.AnyProto[0].Any.CIDR.root.value)
fw = NewFirewall(time.Second, time.Minute, time.Hour, c)
assert.Nil(t, fw.AddRule(false, fwProtoAny, 0, 0, []string{}, "any", nil, "", ""))
assert.True(t, fw.OutRules.AnyProto[0].Any)
assert.True(t, fw.OutRules.AnyProto[0].Any.Any)
fw = NewFirewall(time.Second, time.Minute, time.Hour, c)
_, anyIp, _ := net.ParseCIDR("0.0.0.0/0")
assert.Nil(t, fw.AddRule(false, fwProtoAny, 0, 0, []string{}, "", anyIp, "", ""))
assert.True(t, fw.OutRules.AnyProto[0].Any)
assert.True(t, fw.OutRules.AnyProto[0].Any.Any)
// Test error conditions
fw = NewFirewall(time.Second, time.Minute, time.Hour, c)
@ -134,6 +139,11 @@ func TestFirewall_AddRule(t *testing.T) {
}
func TestFirewall_Drop(t *testing.T) {
ob := &bytes.Buffer{}
out := l.Out
l.SetOutput(ob)
defer l.SetOutput(out)
p := FirewallPacket{
ip2int(net.IPv4(1, 2, 3, 4)),
ip2int(net.IPv4(1, 2, 3, 4)),
@ -153,6 +163,7 @@ func TestFirewall_Drop(t *testing.T) {
Name: "host1",
Ips: []*net.IPNet{&ipNet},
Groups: []string{"default-group"},
InvertedGroups: map[string]struct{}{"default-group": {}},
Issuer: "signer-shasum",
},
}
@ -170,6 +181,7 @@ func TestFirewall_Drop(t *testing.T) {
// Drop outbound
assert.True(t, fw.Drop([]byte{}, p, false, &h, cp))
// Allow inbound
resetConntrack(fw)
assert.False(t, fw.Drop([]byte{}, p, true, &h, cp))
// Allow outbound because conntrack
assert.False(t, fw.Drop([]byte{}, p, false, &h, cp))
@ -180,27 +192,31 @@ func TestFirewall_Drop(t *testing.T) {
assert.True(t, fw.Drop([]byte{}, p, false, &h, cp))
p.RemoteIP = oldRemote
// test caSha assertions true
// ensure signer doesn't get in the way of group checks
fw = NewFirewall(time.Second, time.Minute, time.Hour, &c)
assert.Nil(t, fw.AddRule(true, fwProtoAny, 0, 0, []string{"any"}, "", nil, "", "signer-shasum"))
assert.False(t, fw.Drop([]byte{}, p, true, &h, cp))
// test caSha assertions false
fw = NewFirewall(time.Second, time.Minute, time.Hour, &c)
assert.Nil(t, fw.AddRule(true, fwProtoAny, 0, 0, []string{"any"}, "", nil, "", "signer-shasum-nope"))
assert.Nil(t, fw.AddRule(true, fwProtoAny, 0, 0, []string{"nope"}, "", nil, "", "signer-shasum"))
assert.Nil(t, fw.AddRule(true, fwProtoAny, 0, 0, []string{"default-group"}, "", nil, "", "signer-shasum-bad"))
assert.True(t, fw.Drop([]byte{}, p, true, &h, cp))
// test caName true
cp.CAs["signer-shasum"] = &cert.NebulaCertificate{Details: cert.NebulaCertificateDetails{Name: "ca-good"}}
// test caSha doesn't drop on match
fw = NewFirewall(time.Second, time.Minute, time.Hour, &c)
assert.Nil(t, fw.AddRule(true, fwProtoAny, 0, 0, []string{"any"}, "", nil, "ca-good", ""))
assert.Nil(t, fw.AddRule(true, fwProtoAny, 0, 0, []string{"nope"}, "", nil, "", "signer-shasum-bad"))
assert.Nil(t, fw.AddRule(true, fwProtoAny, 0, 0, []string{"default-group"}, "", nil, "", "signer-shasum"))
assert.False(t, fw.Drop([]byte{}, p, true, &h, cp))
// test caName false
// ensure ca name doesn't get in the way of group checks
cp.CAs["signer-shasum"] = &cert.NebulaCertificate{Details: cert.NebulaCertificateDetails{Name: "ca-good"}}
fw = NewFirewall(time.Second, time.Minute, time.Hour, &c)
assert.Nil(t, fw.AddRule(true, fwProtoAny, 0, 0, []string{"any"}, "", nil, "ca-bad", ""))
assert.Nil(t, fw.AddRule(true, fwProtoAny, 0, 0, []string{"nope"}, "", nil, "ca-good", ""))
assert.Nil(t, fw.AddRule(true, fwProtoAny, 0, 0, []string{"default-group"}, "", nil, "ca-good-bad", ""))
assert.True(t, fw.Drop([]byte{}, p, true, &h, cp))
// test caName doesn't drop on match
cp.CAs["signer-shasum"] = &cert.NebulaCertificate{Details: cert.NebulaCertificateDetails{Name: "ca-good"}}
fw = NewFirewall(time.Second, time.Minute, time.Hour, &c)
assert.Nil(t, fw.AddRule(true, fwProtoAny, 0, 0, []string{"nope"}, "", nil, "ca-good-bad", ""))
assert.Nil(t, fw.AddRule(true, fwProtoAny, 0, 0, []string{"default-group"}, "", nil, "ca-good", ""))
assert.False(t, fw.Drop([]byte{}, p, true, &h, cp))
}
func BenchmarkFirewallTable_match(b *testing.B) {
@ -209,11 +225,11 @@ func BenchmarkFirewallTable_match(b *testing.B) {
}
_, n, _ := net.ParseCIDR("172.1.1.1/32")
ft.TCP.addRule(10, 10, []string{"good-group"}, "good-host", n, "", "")
ft.TCP.addRule(10, 10, []string{"good-group2"}, "good-host", n, "", "")
ft.TCP.addRule(10, 10, []string{"good-group3"}, "good-host", n, "", "")
ft.TCP.addRule(10, 10, []string{"good-group4"}, "good-host", n, "", "")
ft.TCP.addRule(10, 10, []string{"good-group, good-group1"}, "good-host", n, "", "")
_ = ft.TCP.addRule(10, 10, []string{"good-group"}, "good-host", n, "", "")
_ = ft.TCP.addRule(10, 10, []string{"good-group2"}, "good-host", n, "", "")
_ = ft.TCP.addRule(10, 10, []string{"good-group3"}, "good-host", n, "", "")
_ = ft.TCP.addRule(10, 10, []string{"good-group4"}, "good-host", n, "", "")
_ = ft.TCP.addRule(10, 10, []string{"good-group, good-group1"}, "good-host", n, "", "")
cp := cert.NewCAPool()
b.Run("fail on proto", func(b *testing.B) {
@ -281,7 +297,7 @@ func BenchmarkFirewallTable_match(b *testing.B) {
}
})
ft.TCP.addRule(0, 0, []string{"good-group"}, "good-host", n, "", "")
_ = ft.TCP.addRule(0, 0, []string{"good-group"}, "good-host", n, "", "")
b.Run("pass on ip with any port", func(b *testing.B) {
ip := ip2int(net.IPv4(172, 1, 1, 1))
@ -298,6 +314,11 @@ func BenchmarkFirewallTable_match(b *testing.B) {
}
func TestFirewall_Drop2(t *testing.T) {
ob := &bytes.Buffer{}
out := l.Out
l.SetOutput(ob)
defer l.SetOutput(out)
p := FirewallPacket{
ip2int(net.IPv4(1, 2, 3, 4)),
ip2int(net.IPv4(1, 2, 3, 4)),
@ -347,9 +368,94 @@ func TestFirewall_Drop2(t *testing.T) {
// h1/c1 lacks the proper groups
assert.True(t, fw.Drop([]byte{}, p, true, &h1, cp))
// c has the proper groups
resetConntrack(fw)
assert.False(t, fw.Drop([]byte{}, p, true, &h, cp))
}
func TestFirewall_Drop3(t *testing.T) {
ob := &bytes.Buffer{}
out := l.Out
l.SetOutput(ob)
defer l.SetOutput(out)
p := FirewallPacket{
ip2int(net.IPv4(1, 2, 3, 4)),
ip2int(net.IPv4(1, 2, 3, 4)),
1,
1,
fwProtoUDP,
false,
}
ipNet := net.IPNet{
IP: net.IPv4(1, 2, 3, 4),
Mask: net.IPMask{255, 255, 255, 0},
}
c := cert.NebulaCertificate{
Details: cert.NebulaCertificateDetails{
Name: "host-owner",
Ips: []*net.IPNet{&ipNet},
},
}
c1 := cert.NebulaCertificate{
Details: cert.NebulaCertificateDetails{
Name: "host1",
Ips: []*net.IPNet{&ipNet},
Issuer: "signer-sha-bad",
},
}
h1 := HostInfo{
ConnectionState: &ConnectionState{
peerCert: &c1,
},
}
h1.CreateRemoteCIDR(&c1)
c2 := cert.NebulaCertificate{
Details: cert.NebulaCertificateDetails{
Name: "host2",
Ips: []*net.IPNet{&ipNet},
Issuer: "signer-sha",
},
}
h2 := HostInfo{
ConnectionState: &ConnectionState{
peerCert: &c2,
},
}
h2.CreateRemoteCIDR(&c2)
c3 := cert.NebulaCertificate{
Details: cert.NebulaCertificateDetails{
Name: "host3",
Ips: []*net.IPNet{&ipNet},
Issuer: "signer-sha-bad",
},
}
h3 := HostInfo{
ConnectionState: &ConnectionState{
peerCert: &c3,
},
}
h3.CreateRemoteCIDR(&c3)
fw := NewFirewall(time.Second, time.Minute, time.Hour, &c)
assert.Nil(t, fw.AddRule(true, fwProtoAny, 1, 1, []string{}, "host1", nil, "", ""))
assert.Nil(t, fw.AddRule(true, fwProtoAny, 1, 1, []string{}, "", nil, "", "signer-sha"))
cp := cert.NewCAPool()
// c1 should pass because host match
assert.False(t, fw.Drop([]byte{}, p, true, &h1, cp))
// c2 should pass because ca sha match
resetConntrack(fw)
assert.False(t, fw.Drop([]byte{}, p, true, &h2, cp))
// c3 should fail because no match
resetConntrack(fw)
assert.True(t, fw.Drop([]byte{}, p, true, &h3, cp))
}
func BenchmarkLookup(b *testing.B) {
ml := func(m map[string]struct{}, a [][]string) {
for n := 0; n < b.N; n++ {
@ -748,3 +854,9 @@ func (mf *mockFirewall) AddRule(incoming bool, proto uint8, startPort int32, end
mf.nextCallReturn = nil
return err
}
func resetConntrack(fw *Firewall) {
fw.connMutex.Lock()
fw.Conns = map[FirewallPacket]*conn{}
fw.connMutex.Unlock()
}