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Diffstat (limited to 'pkg/tcpip/network/ipv4/ipv4.go')
-rw-r--r--pkg/tcpip/network/ipv4/ipv4.go116
1 files changed, 66 insertions, 50 deletions
diff --git a/pkg/tcpip/network/ipv4/ipv4.go b/pkg/tcpip/network/ipv4/ipv4.go
index ac16c8add..040329a74 100644
--- a/pkg/tcpip/network/ipv4/ipv4.go
+++ b/pkg/tcpip/network/ipv4/ipv4.go
@@ -117,13 +117,14 @@ func (e *endpoint) GSOMaxSize() uint32 {
}
// writePacketFragments calls e.linkEP.WritePacket with each packet fragment to
-// write. It assumes that the IP header is entirely in hdr but does not assume
-// that only the IP header is in hdr. It assumes that the input packet's stated
-// length matches the length of the hdr+payload. mtu includes the IP header and
-// options. This does not support the DontFragment IP flag.
-func (e *endpoint) writePacketFragments(r *stack.Route, gso *stack.GSO, hdr buffer.Prependable, payload buffer.VectorisedView, mtu int) *tcpip.Error {
+// write. It assumes that the IP header is entirely in pkt.Header but does not
+// assume that only the IP header is in pkt.Header. It assumes that the input
+// packet's stated length matches the length of the header+payload. mtu
+// includes the IP header and options. This does not support the DontFragment
+// IP flag.
+func (e *endpoint) writePacketFragments(r *stack.Route, gso *stack.GSO, mtu int, pkt tcpip.PacketBuffer) *tcpip.Error {
// This packet is too big, it needs to be fragmented.
- ip := header.IPv4(hdr.View())
+ ip := header.IPv4(pkt.Header.View())
flags := ip.Flags()
// Update mtu to take into account the header, which will exist in all
@@ -137,62 +138,77 @@ func (e *endpoint) writePacketFragments(r *stack.Route, gso *stack.GSO, hdr buff
outerMTU := innerMTU + int(ip.HeaderLength())
offset := ip.FragmentOffset()
- originalAvailableLength := hdr.AvailableLength()
+ originalAvailableLength := pkt.Header.AvailableLength()
for i := 0; i < n; i++ {
// Where possible, the first fragment that is sent has the same
- // hdr.UsedLength() as the input packet. The link-layer endpoint may depends
- // on this for looking at, eg, L4 headers.
+ // pkt.Header.UsedLength() as the input packet. The link-layer
+ // endpoint may depend on this for looking at, eg, L4 headers.
h := ip
if i > 0 {
- hdr = buffer.NewPrependable(int(ip.HeaderLength()) + originalAvailableLength)
- h = header.IPv4(hdr.Prepend(int(ip.HeaderLength())))
+ pkt.Header = buffer.NewPrependable(int(ip.HeaderLength()) + originalAvailableLength)
+ h = header.IPv4(pkt.Header.Prepend(int(ip.HeaderLength())))
copy(h, ip[:ip.HeaderLength()])
}
if i != n-1 {
h.SetTotalLength(uint16(outerMTU))
h.SetFlagsFragmentOffset(flags|header.IPv4FlagMoreFragments, offset)
} else {
- h.SetTotalLength(uint16(h.HeaderLength()) + uint16(payload.Size()))
+ h.SetTotalLength(uint16(h.HeaderLength()) + uint16(pkt.Data.Size()))
h.SetFlagsFragmentOffset(flags, offset)
}
h.SetChecksum(0)
h.SetChecksum(^h.CalculateChecksum())
offset += uint16(innerMTU)
if i > 0 {
- newPayload := payload.Clone([]buffer.View{})
+ newPayload := pkt.Data.Clone(nil)
newPayload.CapLength(innerMTU)
- if err := e.linkEP.WritePacket(r, gso, hdr, newPayload, ProtocolNumber); err != nil {
+ if err := e.linkEP.WritePacket(r, gso, ProtocolNumber, tcpip.PacketBuffer{
+ Header: pkt.Header,
+ Data: newPayload,
+ NetworkHeader: buffer.View(h),
+ }); err != nil {
return err
}
r.Stats().IP.PacketsSent.Increment()
- payload.TrimFront(newPayload.Size())
+ pkt.Data.TrimFront(newPayload.Size())
continue
}
- // Special handling for the first fragment because it comes from the hdr.
- if outerMTU >= hdr.UsedLength() {
- // This fragment can fit all of hdr and possibly some of payload, too.
- newPayload := payload.Clone([]buffer.View{})
- newPayloadLength := outerMTU - hdr.UsedLength()
+ // Special handling for the first fragment because it comes
+ // from the header.
+ if outerMTU >= pkt.Header.UsedLength() {
+ // This fragment can fit all of pkt.Header and possibly
+ // some of pkt.Data, too.
+ newPayload := pkt.Data.Clone(nil)
+ newPayloadLength := outerMTU - pkt.Header.UsedLength()
newPayload.CapLength(newPayloadLength)
- if err := e.linkEP.WritePacket(r, gso, hdr, newPayload, ProtocolNumber); err != nil {
+ if err := e.linkEP.WritePacket(r, gso, ProtocolNumber, tcpip.PacketBuffer{
+ Header: pkt.Header,
+ Data: newPayload,
+ NetworkHeader: buffer.View(h),
+ }); err != nil {
return err
}
r.Stats().IP.PacketsSent.Increment()
- payload.TrimFront(newPayloadLength)
+ pkt.Data.TrimFront(newPayloadLength)
} else {
- // The fragment is too small to fit all of hdr.
- startOfHdr := hdr
- startOfHdr.TrimBack(hdr.UsedLength() - outerMTU)
+ // The fragment is too small to fit all of pkt.Header.
+ startOfHdr := pkt.Header
+ startOfHdr.TrimBack(pkt.Header.UsedLength() - outerMTU)
emptyVV := buffer.NewVectorisedView(0, []buffer.View{})
- if err := e.linkEP.WritePacket(r, gso, startOfHdr, emptyVV, ProtocolNumber); err != nil {
+ if err := e.linkEP.WritePacket(r, gso, ProtocolNumber, tcpip.PacketBuffer{
+ Header: startOfHdr,
+ Data: emptyVV,
+ NetworkHeader: buffer.View(h),
+ }); err != nil {
return err
}
r.Stats().IP.PacketsSent.Increment()
- // Add the unused bytes of hdr into the payload that remains to be sent.
- restOfHdr := hdr.View()[outerMTU:]
+ // Add the unused bytes of pkt.Header into the pkt.Data
+ // that remains to be sent.
+ restOfHdr := pkt.Header.View()[outerMTU:]
tmp := buffer.NewVectorisedView(len(restOfHdr), []buffer.View{buffer.NewViewFromBytes(restOfHdr)})
- tmp.Append(payload)
- payload = tmp
+ tmp.Append(pkt.Data)
+ pkt.Data = tmp
}
}
return nil
@@ -222,17 +238,17 @@ func (e *endpoint) addIPHeader(r *stack.Route, hdr *buffer.Prependable, payloadS
}
// WritePacket writes a packet to the given destination address and protocol.
-func (e *endpoint) WritePacket(r *stack.Route, gso *stack.GSO, hdr buffer.Prependable, payload buffer.VectorisedView, params stack.NetworkHeaderParams, loop stack.PacketLooping) *tcpip.Error {
- ip := e.addIPHeader(r, &hdr, payload.Size(), params)
+func (e *endpoint) WritePacket(r *stack.Route, gso *stack.GSO, params stack.NetworkHeaderParams, loop stack.PacketLooping, pkt tcpip.PacketBuffer) *tcpip.Error {
+ ip := e.addIPHeader(r, &pkt.Header, pkt.Data.Size(), params)
if loop&stack.PacketLoop != 0 {
- views := make([]buffer.View, 1, 1+len(payload.Views()))
- views[0] = hdr.View()
- views = append(views, payload.Views()...)
+ views := make([]buffer.View, 1, 1+len(pkt.Data.Views()))
+ views[0] = pkt.Header.View()
+ views = append(views, pkt.Data.Views()...)
loopedR := r.MakeLoopedRoute()
e.HandlePacket(&loopedR, tcpip.PacketBuffer{
- Data: buffer.NewVectorisedView(len(views[0])+payload.Size(), views),
+ Data: buffer.NewVectorisedView(len(views[0])+pkt.Data.Size(), views),
NetworkHeader: buffer.View(ip),
})
@@ -241,10 +257,10 @@ func (e *endpoint) WritePacket(r *stack.Route, gso *stack.GSO, hdr buffer.Prepen
if loop&stack.PacketOut == 0 {
return nil
}
- if hdr.UsedLength()+payload.Size() > int(e.linkEP.MTU()) && (gso == nil || gso.Type == stack.GSONone) {
- return e.writePacketFragments(r, gso, hdr, payload, int(e.linkEP.MTU()))
+ if pkt.Header.UsedLength()+pkt.Data.Size() > int(e.linkEP.MTU()) && (gso == nil || gso.Type == stack.GSONone) {
+ return e.writePacketFragments(r, gso, int(e.linkEP.MTU()), pkt)
}
- if err := e.linkEP.WritePacket(r, gso, hdr, payload, ProtocolNumber); err != nil {
+ if err := e.linkEP.WritePacket(r, gso, ProtocolNumber, pkt); err != nil {
return err
}
r.Stats().IP.PacketsSent.Increment()
@@ -270,16 +286,16 @@ func (e *endpoint) WritePackets(r *stack.Route, gso *stack.GSO, hdrs []stack.Pac
// WriteHeaderIncludedPacket writes a packet already containing a network
// header through the given route.
-func (e *endpoint) WriteHeaderIncludedPacket(r *stack.Route, payload buffer.VectorisedView, loop stack.PacketLooping) *tcpip.Error {
+func (e *endpoint) WriteHeaderIncludedPacket(r *stack.Route, loop stack.PacketLooping, pkt tcpip.PacketBuffer) *tcpip.Error {
// The packet already has an IP header, but there are a few required
// checks.
- ip := header.IPv4(payload.First())
- if !ip.IsValid(payload.Size()) {
+ ip := header.IPv4(pkt.Data.First())
+ if !ip.IsValid(pkt.Data.Size()) {
return tcpip.ErrInvalidOptionValue
}
// Always set the total length.
- ip.SetTotalLength(uint16(payload.Size()))
+ ip.SetTotalLength(uint16(pkt.Data.Size()))
// Set the source address when zero.
if ip.SourceAddress() == tcpip.Address(([]byte{0, 0, 0, 0})) {
@@ -293,7 +309,7 @@ func (e *endpoint) WriteHeaderIncludedPacket(r *stack.Route, payload buffer.Vect
// Set the packet ID when zero.
if ip.ID() == 0 {
id := uint32(0)
- if payload.Size() > header.IPv4MaximumHeaderSize+8 {
+ if pkt.Data.Size() > header.IPv4MaximumHeaderSize+8 {
// Packets of 68 bytes or less are required by RFC 791 to not be
// fragmented, so we only assign ids to larger packets.
id = atomic.AddUint32(&e.protocol.ids[hashRoute(r, 0 /* protocol */, e.protocol.hashIV)%buckets], 1)
@@ -306,18 +322,18 @@ func (e *endpoint) WriteHeaderIncludedPacket(r *stack.Route, payload buffer.Vect
ip.SetChecksum(^ip.CalculateChecksum())
if loop&stack.PacketLoop != 0 {
- e.HandlePacket(r, tcpip.PacketBuffer{
- Data: payload,
- NetworkHeader: buffer.View(ip),
- })
+ e.HandlePacket(r, pkt.Clone())
}
if loop&stack.PacketOut == 0 {
return nil
}
- hdr := buffer.NewPrependableFromView(payload.ToView())
r.Stats().IP.PacketsSent.Increment()
- return e.linkEP.WritePacket(r, nil /* gso */, hdr, buffer.VectorisedView{}, ProtocolNumber)
+
+ ip = ip[:ip.HeaderLength()]
+ pkt.Header = buffer.NewPrependableFromView(buffer.View(ip))
+ pkt.Data.TrimFront(int(ip.HeaderLength()))
+ return e.linkEP.WritePacket(r, nil /* gso */, ProtocolNumber, pkt)
}
// HandlePacket is called by the link layer when new ipv4 packets arrive for
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-06 22:45:39 +0000