extern/netbird
1
0
Fork 0
mirror of https://github.com/netbirdio/netbird.git synced 2025-06-20 17:58:02 +02:00
Code Issues Packages Projects Releases Wiki Activity

[client] Support IP fragmentation in userspace (#3639)

Browse Source
This commit is contained in:
Viktor Liu 2025-04-08 12:49:14 +02:00 committed by GitHub
parent 4db78db49a
commit 192c97aa63
No known key found for this signature in database
GPG Key ID: B5690EEEBB952194
1 changed files with 30 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

37
client/firewall/uspfilter/uspfilter.go
View File

@ -658,7 +658,8 @@ func (m *Manager) dropFilter(packetData []byte, size int) bool {
d := m.decoders.Get().(*decoder) d := m.decoders.Get().(*decoder)
defer m.decoders.Put(d) defer m.decoders.Put(d)
if !m.isValidPacket(d, packetData) { valid, fragment := m.isValidPacket(d, packetData)
if !valid {
return true return true
} }
@ -668,6 +669,13 @@ func (m *Manager) dropFilter(packetData []byte, size int) bool {
return true return true
} }
// TODO: pass fragments of routed packets to forwarder
if fragment {
m.logger.Trace("packet is a fragment: src=%v dst=%v id=%v flags=%v",
srcIP, dstIP, d.ip4.Id, d.ip4.Flags)
return false
}
// For all inbound traffic, first check if it matches a tracked connection. // For all inbound traffic, first check if it matches a tracked connection.
// This must happen before any other filtering because the packets are statefully tracked. // This must happen before any other filtering because the packets are statefully tracked.
if m.stateful && m.isValidTrackedConnection(d, srcIP, dstIP, size) { if m.stateful && m.isValidTrackedConnection(d, srcIP, dstIP, size) {
@ -815,17 +823,32 @@ func getPortsFromPacket(d *decoder) (srcPort, dstPort uint16) {
} }
} }
func (m *Manager) isValidPacket(d *decoder, packetData []byte) bool { // isValidPacket checks if the packet is valid.
// It returns true, false if the packet is valid and not a fragment.
// It returns true, true if the packet is a fragment and valid.
func (m *Manager) isValidPacket(d *decoder, packetData []byte) (bool, bool) {
if err := d.parser.DecodeLayers(packetData, &d.decoded); err != nil { if err := d.parser.DecodeLayers(packetData, &d.decoded); err != nil {
m.logger.Trace("couldn't decode packet, err: %s", err) m.logger.Trace("couldn't decode packet, err: %s", err)
return false return false, false
} }
if len(d.decoded) < 2 { l := len(d.decoded)
m.logger.Trace("packet doesn't have network and transport layers")
return false // L3 and L4 are mandatory
if l >= 2 {
return true, false
} }
return true
// Fragments are also valid
if l == 1 && d.decoded[0] == layers.LayerTypeIPv4 {
ip4 := d.ip4
if ip4.Flags&layers.IPv4MoreFragments != 0 || ip4.FragOffset != 0 {
return true, true
}
}
m.logger.Trace("packet doesn't have network and transport layers")
return false, false
} }
func (m *Manager) isValidTrackedConnection(d *decoder, srcIP, dstIP netip.Addr, size int) bool { func (m *Manager) isValidTrackedConnection(d *decoder, srcIP, dstIP netip.Addr, size int) bool {