diff options
Diffstat (limited to 'pkg/tcpip')
-rw-r--r-- | pkg/tcpip/stack/conntrack.go | 40 | ||||
-rw-r--r-- | pkg/tcpip/stack/iptables.go | 4 | ||||
-rw-r--r-- | pkg/tcpip/stack/iptables_targets.go | 28 | ||||
-rw-r--r-- | pkg/tcpip/stack/packet_buffer.go | 15 | ||||
-rw-r--r-- | pkg/tcpip/transport/tcp/endpoint.go | 2 |
5 files changed, 60 insertions, 29 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. diff --git a/pkg/tcpip/transport/tcp/endpoint.go b/pkg/tcpip/transport/tcp/endpoint.go index 7ad894840..ae817091a 100644 --- a/pkg/tcpip/transport/tcp/endpoint.go +++ b/pkg/tcpip/transport/tcp/endpoint.go @@ -2099,7 +2099,7 @@ func (e *endpoint) GetSockOpt(opt tcpip.GettableSocketOption) *tcpip.Error { case *tcpip.OriginalDestinationOption: e.LockUser() ipt := e.stack.IPTables() - addr, port, err := ipt.OriginalDst(e.ID) + addr, port, err := ipt.OriginalDst(e.ID, e.NetProto) e.UnlockUser() if err != nil { return err |