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-rw-r--r--pkg/tcpip/stack/conntrack.go40
-rw-r--r--pkg/tcpip/stack/iptables.go4
-rw-r--r--pkg/tcpip/stack/iptables_targets.go28
-rw-r--r--pkg/tcpip/stack/packet_buffer.go15
4 files changed, 59 insertions, 28 deletions
diff --git a/pkg/tcpip/stack/conntrack.go b/pkg/tcpip/stack/conntrack.go
index 457f0c89b..0cd1da11f 100644
--- a/pkg/tcpip/stack/conntrack.go
+++ b/pkg/tcpip/stack/conntrack.go
@@ -196,13 +196,14 @@ type bucket struct {
// packetToTupleID converts packet to a tuple ID. It fails when pkt lacks a valid
// TCP header.
+//
+// Preconditions: pkt.NetworkHeader() is valid.
func packetToTupleID(pkt *PacketBuffer) (tupleID, *tcpip.Error) {
- // TODO(gvisor.dev/issue/170): Need to support for other
- // protocols as well.
- netHeader := header.IPv4(pkt.NetworkHeader().View())
- if len(netHeader) < header.IPv4MinimumSize || netHeader.TransportProtocol() != header.TCPProtocolNumber {
+ netHeader := pkt.Network()
+ if netHeader.TransportProtocol() != header.TCPProtocolNumber {
return tupleID{}, tcpip.ErrUnknownProtocol
}
+
tcpHeader := header.TCP(pkt.TransportHeader().View())
if len(tcpHeader) < header.TCPMinimumSize {
return tupleID{}, tcpip.ErrUnknownProtocol
@@ -214,7 +215,7 @@ func packetToTupleID(pkt *PacketBuffer) (tupleID, *tcpip.Error) {
dstAddr: netHeader.DestinationAddress(),
dstPort: tcpHeader.DestinationPort(),
transProto: netHeader.TransportProtocol(),
- netProto: header.IPv4ProtocolNumber,
+ netProto: pkt.NetworkProtocolNumber,
}, nil
}
@@ -344,7 +345,7 @@ func handlePacketPrerouting(pkt *PacketBuffer, conn *conn, dir direction) {
return
}
- netHeader := header.IPv4(pkt.NetworkHeader().View())
+ netHeader := pkt.Network()
tcpHeader := header.TCP(pkt.TransportHeader().View())
// For prerouting redirection, packets going in the original direction
@@ -366,8 +367,12 @@ func handlePacketPrerouting(pkt *PacketBuffer, conn *conn, dir direction) {
// support cases when they are validated, e.g. when we can't offload
// receive checksumming.
- netHeader.SetChecksum(0)
- netHeader.SetChecksum(^netHeader.CalculateChecksum())
+ // After modification, IPv4 packets need a valid checksum.
+ if pkt.NetworkProtocolNumber == header.IPv4ProtocolNumber {
+ netHeader := header.IPv4(pkt.NetworkHeader().View())
+ netHeader.SetChecksum(0)
+ netHeader.SetChecksum(^netHeader.CalculateChecksum())
+ }
}
// handlePacketOutput manipulates ports for packets in Output hook.
@@ -377,7 +382,7 @@ func handlePacketOutput(pkt *PacketBuffer, conn *conn, gso *GSO, r *Route, dir d
return
}
- netHeader := header.IPv4(pkt.NetworkHeader().View())
+ netHeader := pkt.Network()
tcpHeader := header.TCP(pkt.TransportHeader().View())
// For output redirection, packets going in the original direction
@@ -396,7 +401,7 @@ func handlePacketOutput(pkt *PacketBuffer, conn *conn, gso *GSO, r *Route, dir d
// Calculate the TCP checksum and set it.
tcpHeader.SetChecksum(0)
- length := uint16(pkt.Size()) - uint16(netHeader.HeaderLength())
+ length := uint16(pkt.Size()) - uint16(len(pkt.NetworkHeader().View()))
xsum := r.PseudoHeaderChecksum(header.TCPProtocolNumber, length)
if gso != nil && gso.NeedsCsum {
tcpHeader.SetChecksum(xsum)
@@ -405,8 +410,11 @@ func handlePacketOutput(pkt *PacketBuffer, conn *conn, gso *GSO, r *Route, dir d
tcpHeader.SetChecksum(^tcpHeader.CalculateChecksum(xsum))
}
- netHeader.SetChecksum(0)
- netHeader.SetChecksum(^netHeader.CalculateChecksum())
+ if pkt.NetworkProtocolNumber == header.IPv4ProtocolNumber {
+ netHeader := header.IPv4(pkt.NetworkHeader().View())
+ netHeader.SetChecksum(0)
+ netHeader.SetChecksum(^netHeader.CalculateChecksum())
+ }
}
// handlePacket will manipulate the port and address of the packet if the
@@ -422,7 +430,7 @@ func (ct *ConnTrack) handlePacket(pkt *PacketBuffer, hook Hook, gso *GSO, r *Rou
}
// TODO(gvisor.dev/issue/170): Support other transport protocols.
- if nh := pkt.NetworkHeader().View(); nh.IsEmpty() || header.IPv4(nh).TransportProtocol() != header.TCPProtocolNumber {
+ if pkt.Network().TransportProtocol() != header.TCPProtocolNumber {
return false
}
@@ -473,7 +481,7 @@ func (ct *ConnTrack) maybeInsertNoop(pkt *PacketBuffer, hook Hook) {
}
// We only track TCP connections.
- if nh := pkt.NetworkHeader().View(); nh.IsEmpty() || header.IPv4(nh).TransportProtocol() != header.TCPProtocolNumber {
+ if pkt.Network().TransportProtocol() != header.TCPProtocolNumber {
return
}
@@ -609,7 +617,7 @@ func (ct *ConnTrack) reapTupleLocked(tuple *tuple, bucket int, now time.Time) bo
return true
}
-func (ct *ConnTrack) originalDst(epID TransportEndpointID) (tcpip.Address, uint16, *tcpip.Error) {
+func (ct *ConnTrack) originalDst(epID TransportEndpointID, netProto tcpip.NetworkProtocolNumber) (tcpip.Address, uint16, *tcpip.Error) {
// Lookup the connection. The reply's original destination
// describes the original address.
tid := tupleID{
@@ -618,7 +626,7 @@ func (ct *ConnTrack) originalDst(epID TransportEndpointID) (tcpip.Address, uint1
dstAddr: epID.RemoteAddress,
dstPort: epID.RemotePort,
transProto: header.TCPProtocolNumber,
- netProto: header.IPv4ProtocolNumber,
+ netProto: netProto,
}
conn, _ := ct.connForTID(tid)
if conn == nil {
diff --git a/pkg/tcpip/stack/iptables.go b/pkg/tcpip/stack/iptables.go
index faa503b00..8d6d9a7f1 100644
--- a/pkg/tcpip/stack/iptables.go
+++ b/pkg/tcpip/stack/iptables.go
@@ -502,11 +502,11 @@ func (it *IPTables) checkRule(hook Hook, pkt *PacketBuffer, table Table, ruleIdx
// OriginalDst returns the original destination of redirected connections. It
// returns an error if the connection doesn't exist or isn't redirected.
-func (it *IPTables) OriginalDst(epID TransportEndpointID) (tcpip.Address, uint16, *tcpip.Error) {
+func (it *IPTables) OriginalDst(epID TransportEndpointID, netProto tcpip.NetworkProtocolNumber) (tcpip.Address, uint16, *tcpip.Error) {
it.mu.RLock()
defer it.mu.RUnlock()
if !it.modified {
return "", 0, tcpip.ErrNotConnected
}
- return it.connections.originalDst(epID)
+ return it.connections.originalDst(epID, netProto)
}
diff --git a/pkg/tcpip/stack/iptables_targets.go b/pkg/tcpip/stack/iptables_targets.go
index 611564b08..538c4625d 100644
--- a/pkg/tcpip/stack/iptables_targets.go
+++ b/pkg/tcpip/stack/iptables_targets.go
@@ -164,11 +164,15 @@ func (rt *RedirectTarget) Action(pkt *PacketBuffer, ct *ConnTrack, hook Hook, gs
return RuleDrop, 0
}
- // Change the address to localhost (127.0.0.1) in Output and
- // to primary address of the incoming interface in Prerouting.
+ // Change the address to localhost (127.0.0.1 or ::1) in Output and to
+ // the primary address of the incoming interface in Prerouting.
switch hook {
case Output:
- rt.Addr = tcpip.Address([]byte{127, 0, 0, 1})
+ if pkt.NetworkProtocolNumber == header.IPv4ProtocolNumber {
+ rt.Addr = tcpip.Address([]byte{127, 0, 0, 1})
+ } else {
+ rt.Addr = header.IPv6Loopback
+ }
case Prerouting:
rt.Addr = address
default:
@@ -177,8 +181,7 @@ func (rt *RedirectTarget) Action(pkt *PacketBuffer, ct *ConnTrack, hook Hook, gs
// TODO(gvisor.dev/issue/170): Check Flags in RedirectTarget if
// we need to change dest address (for OUTPUT chain) or ports.
- netHeader := header.IPv4(pkt.NetworkHeader().View())
- switch protocol := netHeader.TransportProtocol(); protocol {
+ switch protocol := pkt.TransportProtocolNumber; protocol {
case header.UDPProtocolNumber:
udpHeader := header.UDP(pkt.TransportHeader().View())
udpHeader.SetDestinationPort(rt.Port)
@@ -186,10 +189,10 @@ func (rt *RedirectTarget) Action(pkt *PacketBuffer, ct *ConnTrack, hook Hook, gs
// Calculate UDP checksum and set it.
if hook == Output {
udpHeader.SetChecksum(0)
- length := uint16(pkt.Size()) - uint16(netHeader.HeaderLength())
// Only calculate the checksum if offloading isn't supported.
if r.Capabilities()&CapabilityTXChecksumOffload == 0 {
+ length := uint16(pkt.Size()) - uint16(len(pkt.NetworkHeader().View()))
xsum := r.PseudoHeaderChecksum(protocol, length)
for _, v := range pkt.Data.Views() {
xsum = header.Checksum(v, xsum)
@@ -198,10 +201,15 @@ func (rt *RedirectTarget) Action(pkt *PacketBuffer, ct *ConnTrack, hook Hook, gs
udpHeader.SetChecksum(^udpHeader.CalculateChecksum(xsum))
}
}
- // Change destination address.
- netHeader.SetDestinationAddress(rt.Addr)
- netHeader.SetChecksum(0)
- netHeader.SetChecksum(^netHeader.CalculateChecksum())
+
+ pkt.Network().SetDestinationAddress(rt.Addr)
+
+ // After modification, IPv4 packets need a valid checksum.
+ if pkt.NetworkProtocolNumber == header.IPv4ProtocolNumber {
+ netHeader := header.IPv4(pkt.NetworkHeader().View())
+ netHeader.SetChecksum(0)
+ netHeader.SetChecksum(^netHeader.CalculateChecksum())
+ }
pkt.NatDone = true
case header.TCPProtocolNumber:
if ct == nil {
diff --git a/pkg/tcpip/stack/packet_buffer.go b/pkg/tcpip/stack/packet_buffer.go
index a7d9d59fa..105583c49 100644
--- a/pkg/tcpip/stack/packet_buffer.go
+++ b/pkg/tcpip/stack/packet_buffer.go
@@ -19,6 +19,7 @@ import (
"gvisor.dev/gvisor/pkg/sync"
"gvisor.dev/gvisor/pkg/tcpip"
"gvisor.dev/gvisor/pkg/tcpip/buffer"
+ "gvisor.dev/gvisor/pkg/tcpip/header"
)
type headerType int
@@ -255,6 +256,20 @@ func (pk *PacketBuffer) Clone() *PacketBuffer {
return newPk
}
+// Network returns the network header as a header.Network.
+//
+// Network should only be called when NetworkHeader has been set.
+func (pk *PacketBuffer) Network() header.Network {
+ switch netProto := pk.NetworkProtocolNumber; netProto {
+ case header.IPv4ProtocolNumber:
+ return header.IPv4(pk.NetworkHeader().View())
+ case header.IPv6ProtocolNumber:
+ return header.IPv6(pk.NetworkHeader().View())
+ default:
+ panic(fmt.Sprintf("unknown network protocol number %d", netProto))
+ }
+}
+
// headerInfo stores metadata about a header in a packet.
type headerInfo struct {
// buf is the memorized slice for both prepended and consumed header.
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-15 03:57:12 +0000