vanja/gluetun
1
0
Fork 0
mirror of https://github.com/qdm12/gluetun.git synced 2026-08-11 14:52:56 +02:00
Code Issues Packages Projects Releases Wiki Activity

human review!

Browse Source
This commit is contained in:
Quentin McGaw
2026-08-06 20:08:38 +00:00
parent 0f337b4277
commit c513b8fbd2
6 changed files with 73 additions and 164 deletions
Download Patch File Download Diff File Expand all files Collapse all files
internal/firewall/nftables/output.go
+58 -154
View File
@@ -10,6 +10,22 @@ import (
"github.com/qdm12/gluetun/internal/models"
)
// cidrMask returns the binary mask for a CIDR prefix length.
//
//nolint:mnd
func cidrMask(bits, addrLen int) []byte {
result := make([]byte, addrLen)
fullBytes := bits / 8
remainingBits := bits % 8
for i := range fullBytes {
result[i] = 0xff
}
if remainingBits > 0 {
result[fullBytes] = byte((0xff << (8 - remainingBits)) & 0xff)
}
return result
}
func (f *Firewall) AcceptIpv6MulticastOutput(_ context.Context, intf string) error {
f.mutex.Lock()
defer f.mutex.Unlock()
@@ -35,17 +51,17 @@ func (f *Firewall) AcceptIpv6MulticastOutput(_ context.Context, intf string) err
mask := []byte{
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00,
} //nolint:mnd
}
addr := []byte{
0xff, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x01, 0xff, 0x00, 0x00, 0x00,
} //nolint:mnd
}
exprs = append(exprs,
&expr.Payload{
DestRegister: 1,
Base: expr.PayloadBaseNetworkHeader,
Offset: 24, // IPv6 Destination Address offset //nolint:mnd
Offset: 24, //nolint:mnd // IPv6 Destination Address offset
Len: 16, //nolint:mnd
},
&expr.Bitwise{
@@ -53,7 +69,7 @@ func (f *Firewall) AcceptIpv6MulticastOutput(_ context.Context, intf string) err
DestRegister: 1,
Len: 16, //nolint:mnd
Mask: mask,
Xor: []byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}, //nolint:mnd
Xor: []byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
},
&expr.Cmp{
Op: expr.CmpOpEq,
@@ -79,8 +95,9 @@ func (f *Firewall) AcceptIpv6MulticastOutput(_ context.Context, intf string) err
return nil
}
func (f *Firewall) AcceptOutputTrafficToVPN(_ context.Context, defaultInterface string,
connection models.Connection, remove bool) error {
func (f *Firewall) AcceptOutputTrafficToVPN(_ context.Context, defaultInterface string,
connection models.Connection, remove bool,
) error {
f.mutex.Lock()
defer f.mutex.Unlock()
@@ -109,8 +126,8 @@ func (f *Firewall) AcceptOutputTrafficToVPN(_ context.Context, defaultInterface
&expr.Payload{
DestRegister: 1,
Base: expr.PayloadBaseNetworkHeader,
Offset: 16, // IPv4 destination address offset
Len: 4, //nolint:mnd
Offset: 16, //nolint:mnd // IPv4 destination address offset
Len: 4, //nolint:mnd
},
&expr.Cmp{
Op: expr.CmpOpEq,
@@ -123,7 +140,7 @@ func (f *Firewall) AcceptOutputTrafficToVPN(_ context.Context, defaultInterface
&expr.Payload{
DestRegister: 1,
Base: expr.PayloadBaseNetworkHeader,
Offset: 24, // IPv6 destination address offset
Offset: 24, //nolint:mnd// IPv6 destination address offset
Len: 16, //nolint:mnd
},
&expr.Cmp{
@@ -136,21 +153,17 @@ func (f *Firewall) AcceptOutputTrafficToVPN(_ context.Context, defaultInterface
// Protocol (tcp or udp)
var protocolByte uint8
if connection.Protocol == "tcp" || connection.Protocol == "tcp-client" {
switch connection.Protocol {
case "tcp", "tcp-client":
protocolByte = 6 // TCP
} else if connection.Protocol == "udp" {
case "udp":
protocolByte = 17 // UDP
} else {
default:
return fmt.Errorf("unsupported protocol: %s", connection.Protocol)
}
exprs = append(exprs,
&expr.Payload{
DestRegister: 1,
Base: expr.PayloadBaseTransportHeader,
Offset: 3, // Protocol byte offset in IP header
Len: 1,
},
&expr.Meta{Key: expr.MetaKeyL4PROTO, Register: 1},
&expr.Cmp{
Op: expr.CmpOpEq,
Register: 1,
@@ -159,130 +172,12 @@ func (f *Firewall) AcceptOutputTrafficToVPN(_ context.Context, defaultInterface
)
// Destination port
portBytes := []byte{byte(connection.Port >> 8), byte(connection.Port)} //nolint:mnd
portBytes := []byte{byte(connection.Port >> 8), byte(connection.Port)} //nolint:mnd,gosec
exprs = append(exprs,
&expr.Payload{
DestRegister: 1,
Base: expr.PayloadBaseTransportHeader,
Offset: 2, // destination port offset
Len: 2, //nolint:mnd
},
&expr.Cmp{
Op: expr.CmpOpEq,
Register: 1,
Data: portBytes,
},
&expr.Verdict{Kind: expr.VerdictAccept},
)
rule := &nftables.Rule{
Table: table,
Chain: outputChain,
Exprs: exprs,
}
if !remove {
conn.AddRule(rule)
f.rules = append(f.rules, rule)
} else {
err = f.deleteRule(conn, rule)
if err != nil {
return fmt.Errorf("deleting rule: %w", err)
}
}
err = conn.Flush()
if err != nil {
if !remove {
f.rules = f.rules[:len(f.rules)-1]
}
return fmt.Errorf("flushing: %w", err)
}
return nil
}
func (f *Firewall) AcceptOutput(_ context.Context, protocol, intf string, ip netip.Addr, port uint16, remove bool) error {
f.mutex.Lock()
defer f.mutex.Unlock()
conn, err := nftables.New()
if err != nil {
return fmt.Errorf("creating nftables connection: %w", err)
}
table, _, _, outputChain := setupFilterWithBaseChains(conn)
const maxExprsLen = 7
exprs := make([]expr.Any, 0, maxExprsLen)
if intf != "" && intf != "*" {
exprs = append(exprs,
&expr.Meta{Key: expr.MetaKeyOIFNAME, Register: 1},
&expr.Cmp{Op: expr.CmpOpEq, Register: 1, Data: []byte(intf + "\x00")},
)
}
if ip.Is4() {
exprs = append(exprs,
&expr.Payload{
DestRegister: 1,
Base: expr.PayloadBaseNetworkHeader,
Offset: 16, //nolint:mnd
Len: 4, //nolint:mnd
},
&expr.Cmp{
Op: expr.CmpOpEq,
Register: 1,
Data: ip.AsSlice(),
},
)
} else {
exprs = append(exprs,
&expr.Payload{
DestRegister: 1,
Base: expr.PayloadBaseNetworkHeader,
Offset: 24, //nolint:mnd
Len: 16, //nolint:mnd
},
&expr.Cmp{
Op: expr.CmpOpEq,
Register: 1,
Data: ip.AsSlice(),
},
)
}
var protocolByte uint8
switch protocol {
case "tcp":
protocolByte = 6 //nolint:mnd
case "udp":
protocolByte = 17 //nolint:mnd
default:
return fmt.Errorf("unsupported protocol: %s", protocol)
}
exprs = append(exprs,
&expr.Payload{
DestRegister: 1,
Base: expr.PayloadBaseTransportHeader,
Offset: 3, //nolint:mnd
Len: 1,
},
&expr.Cmp{
Op: expr.CmpOpEq,
Register: 1,
Data: []byte{protocolByte},
},
)
portBytes := []byte{byte(port >> 8), byte(port)} //nolint:mnd
exprs = append(exprs,
&expr.Payload{
DestRegister: 1,
Base: expr.PayloadBaseTransportHeader,
Offset: 2, //nolint:mnd
Offset: 2, //nolint:mnd// destination port offset
Len: 2, //nolint:mnd
},
&expr.Cmp{
@@ -349,7 +244,7 @@ func (f *Firewall) AcceptOutputFromIPPortToIPPort(_ context.Context, protocol, i
DestRegister: 1,
Base: expr.PayloadBaseNetworkHeader,
Offset: 12, //nolint:mnd
Len: 4, //nolint:mnd
Len: 4, //nolint:mnd
},
&expr.Cmp{
Op: expr.CmpOpEq,
@@ -362,7 +257,7 @@ func (f *Firewall) AcceptOutputFromIPPortToIPPort(_ context.Context, protocol, i
&expr.Payload{
DestRegister: 1,
Base: expr.PayloadBaseNetworkHeader,
Offset: 8, //nolint:mnd
Offset: 8, //nolint:mnd
Len: 16, //nolint:mnd
},
&expr.Cmp{
@@ -379,7 +274,7 @@ func (f *Firewall) AcceptOutputFromIPPortToIPPort(_ context.Context, protocol, i
DestRegister: 1,
Base: expr.PayloadBaseNetworkHeader,
Offset: 16, //nolint:mnd
Len: 4, //nolint:mnd
Len: 4, //nolint:mnd
},
&expr.Cmp{
Op: expr.CmpOpEq,
@@ -410,16 +305,11 @@ func (f *Firewall) AcceptOutputFromIPPortToIPPort(_ context.Context, protocol, i
case "udp":
protocolByte = 17 //nolint:mnd
default:
return fmt.Errorf("unsupported protocol: %s", protocol)
return fmt.Errorf("unsupported protocol: %s", protocol) //nolint:err113
}
exprs = append(exprs,
&expr.Payload{
DestRegister: 1,
Base: expr.PayloadBaseTransportHeader,
Offset: 3, //nolint:mnd
Len: 1,
},
&expr.Meta{Key: expr.MetaKeyL4PROTO, Register: 1},
&expr.Cmp{
Op: expr.CmpOpEq,
Register: 1,
@@ -427,7 +317,7 @@ func (f *Firewall) AcceptOutputFromIPPortToIPPort(_ context.Context, protocol, i
},
)
sourcePortBytes := []byte{byte(source.Port() >> 8), byte(source.Port())} //nolint:mnd
sourcePortBytes := []byte{byte(source.Port() >> 8), byte(source.Port())} //nolint:mnd
destinationPortBytes := []byte{byte(destination.Port() >> 8), byte(destination.Port())} //nolint:mnd
exprs = append(exprs,
&expr.Payload{
@@ -511,7 +401,7 @@ func (f *Firewall) AcceptOutputFromIPToSubnet(_ context.Context, intf string, as
DestRegister: 1,
Base: expr.PayloadBaseNetworkHeader,
Offset: 12, //nolint:mnd
Len: 4, //nolint:mnd
Len: 4, //nolint:mnd
},
&expr.Cmp{
Op: expr.CmpOpEq,
@@ -524,7 +414,7 @@ func (f *Firewall) AcceptOutputFromIPToSubnet(_ context.Context, intf string, as
&expr.Payload{
DestRegister: 1,
Base: expr.PayloadBaseNetworkHeader,
Offset: 8, //nolint:mnd
Offset: 8, //nolint:mnd
Len: 16, //nolint:mnd
},
&expr.Cmp{
@@ -536,22 +426,31 @@ func (f *Firewall) AcceptOutputFromIPToSubnet(_ context.Context, intf string, as
}
if subnet.Addr().Is4() {
mask := cidrMask(subnet.Bits(), 4) //nolint:mnd
networkAddr := subnet.Masked().Addr().AsSlice()
exprs = append(exprs,
&expr.Payload{
DestRegister: 1,
Base: expr.PayloadBaseNetworkHeader,
Offset: 16, //nolint:mnd
Len: 4, //nolint:mnd
Len: 4, //nolint:mnd
},
&expr.Bitwise{
SourceRegister: 1,
DestRegister: 1,
Len: 4, //nolint:mnd
Mask: subnet.Masked().Addr().AsSlice(),
Mask: mask,
Xor: []byte{0, 0, 0, 0}, //nolint:mnd
},
&expr.Cmp{
Op: expr.CmpOpEq,
Register: 1,
Data: networkAddr,
},
)
} else {
mask := cidrMask(subnet.Bits(), 16) //nolint:mnd
networkAddr := subnet.Masked().Addr().AsSlice()
exprs = append(exprs,
&expr.Payload{
DestRegister: 1,
@@ -563,9 +462,14 @@ func (f *Firewall) AcceptOutputFromIPToSubnet(_ context.Context, intf string, as
SourceRegister: 1,
DestRegister: 1,
Len: 16, //nolint:mnd
Mask: subnet.Masked().Addr().AsSlice(),
Mask: mask,
Xor: []byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}, //nolint:mnd
},
&expr.Cmp{
Op: expr.CmpOpEq,
Register: 1,
Data: networkAddr,
},
)
}