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-rwxr-xr-xpkg/sentry/socket/netfilter/tcp_matcher.go5
-rwxr-xr-xpkg/sentry/socket/netfilter/udp_matcher.go5
-rw-r--r--pkg/tcpip/buffer/view.go55
-rw-r--r--pkg/tcpip/link/loopback/loopback.go10
-rw-r--r--pkg/tcpip/link/sniffer/sniffer.go65
-rw-r--r--pkg/tcpip/network/arp/arp.go5
-rw-r--r--pkg/tcpip/network/ipv4/icmp.go20
-rw-r--r--pkg/tcpip/network/ipv4/ipv4.go12
-rw-r--r--pkg/tcpip/network/ipv6/icmp.go74
-rw-r--r--pkg/tcpip/network/ipv6/ipv6.go6
-rwxr-xr-xpkg/tcpip/stack/iptables.go22
-rwxr-xr-xpkg/tcpip/stack/iptables_targets.go23
-rw-r--r--pkg/tcpip/stack/nic.go34
-rwxr-xr-xpkg/tcpip/stack/packet_buffer.go4
-rw-r--r--pkg/tcpip/transport/icmp/endpoint.go8
-rw-r--r--pkg/tcpip/transport/tcp/segment.go29
-rw-r--r--pkg/tcpip/transport/udp/endpoint.go6
-rw-r--r--pkg/tcpip/transport/udp/protocol.go9
18 files changed, 260 insertions, 132 deletions
diff --git a/pkg/sentry/socket/netfilter/tcp_matcher.go b/pkg/sentry/socket/netfilter/tcp_matcher.go
index ff1cfd8f6..55c0f04f3 100755
--- a/pkg/sentry/socket/netfilter/tcp_matcher.go
+++ b/pkg/sentry/socket/netfilter/tcp_matcher.go
@@ -121,12 +121,13 @@ func (tm *TCPMatcher) Match(hook stack.Hook, pkt stack.PacketBuffer, interfaceNa
tcpHeader = header.TCP(pkt.TransportHeader)
} else {
// The TCP header hasn't been parsed yet. We have to do it here.
- if len(pkt.Data.First()) < header.TCPMinimumSize {
+ hdr, ok := pkt.Data.PullUp(header.TCPMinimumSize)
+ if !ok {
// There's no valid TCP header here, so we hotdrop the
// packet.
return false, true
}
- tcpHeader = header.TCP(pkt.Data.First())
+ tcpHeader = header.TCP(hdr)
}
// Check whether the source and destination ports are within the
diff --git a/pkg/sentry/socket/netfilter/udp_matcher.go b/pkg/sentry/socket/netfilter/udp_matcher.go
index 3359418c1..04d03d494 100755
--- a/pkg/sentry/socket/netfilter/udp_matcher.go
+++ b/pkg/sentry/socket/netfilter/udp_matcher.go
@@ -120,12 +120,13 @@ func (um *UDPMatcher) Match(hook stack.Hook, pkt stack.PacketBuffer, interfaceNa
udpHeader = header.UDP(pkt.TransportHeader)
} else {
// The UDP header hasn't been parsed yet. We have to do it here.
- if len(pkt.Data.First()) < header.UDPMinimumSize {
+ hdr, ok := pkt.Data.PullUp(header.UDPMinimumSize)
+ if !ok {
// There's no valid UDP header here, so we hotdrop the
// packet.
return false, true
}
- udpHeader = header.UDP(pkt.Data.First())
+ udpHeader = header.UDP(hdr)
}
// Check whether the source and destination ports are within the
diff --git a/pkg/tcpip/buffer/view.go b/pkg/tcpip/buffer/view.go
index 8ec5d5d5c..f01217c91 100644
--- a/pkg/tcpip/buffer/view.go
+++ b/pkg/tcpip/buffer/view.go
@@ -77,7 +77,8 @@ func NewVectorisedView(size int, views []View) VectorisedView {
return VectorisedView{views: views, size: size}
}
-// TrimFront removes the first "count" bytes of the vectorised view.
+// TrimFront removes the first "count" bytes of the vectorised view. It panics
+// if count > vv.Size().
func (vv *VectorisedView) TrimFront(count int) {
for count > 0 && len(vv.views) > 0 {
if count < len(vv.views[0]) {
@@ -86,7 +87,7 @@ func (vv *VectorisedView) TrimFront(count int) {
return
}
count -= len(vv.views[0])
- vv.RemoveFirst()
+ vv.removeFirst()
}
}
@@ -104,7 +105,7 @@ func (vv *VectorisedView) Read(v View) (copied int, err error) {
count -= len(vv.views[0])
copy(v[copied:], vv.views[0])
copied += len(vv.views[0])
- vv.RemoveFirst()
+ vv.removeFirst()
}
if copied == 0 {
return 0, io.EOF
@@ -126,7 +127,7 @@ func (vv *VectorisedView) ReadToVV(dstVV *VectorisedView, count int) (copied int
count -= len(vv.views[0])
dstVV.AppendView(vv.views[0])
copied += len(vv.views[0])
- vv.RemoveFirst()
+ vv.removeFirst()
}
return copied
}
@@ -162,22 +163,37 @@ func (vv *VectorisedView) Clone(buffer []View) VectorisedView {
return VectorisedView{views: append(buffer[:0], vv.views...), size: vv.size}
}
-// First returns the first view of the vectorised view.
-func (vv *VectorisedView) First() View {
+// PullUp returns the first "count" bytes of the vectorised view. If those
+// bytes aren't already contiguous inside the vectorised view, PullUp will
+// reallocate as needed to make them contiguous. PullUp fails and returns false
+// when count > vv.Size().
+func (vv *VectorisedView) PullUp(count int) (View, bool) {
if len(vv.views) == 0 {
- return nil
+ return nil, count == 0
+ }
+ if count <= len(vv.views[0]) {
+ return vv.views[0][:count], true
+ }
+ if count > vv.size {
+ return nil, false
}
- return vv.views[0]
-}
-// RemoveFirst removes the first view of the vectorised view.
-func (vv *VectorisedView) RemoveFirst() {
- if len(vv.views) == 0 {
- return
+ newFirst := NewView(count)
+ i := 0
+ for offset := 0; offset < count; i++ {
+ copy(newFirst[offset:], vv.views[i])
+ if count-offset < len(vv.views[i]) {
+ vv.views[i].TrimFront(count - offset)
+ break
+ }
+ offset += len(vv.views[i])
+ vv.views[i] = nil
}
- vv.size -= len(vv.views[0])
- vv.views[0] = nil
- vv.views = vv.views[1:]
+ // We're guaranteed that i > 0, since count is too large for the first
+ // view.
+ vv.views[i-1] = newFirst
+ vv.views = vv.views[i-1:]
+ return newFirst, true
}
// Size returns the size in bytes of the entire content stored in the vectorised view.
@@ -225,3 +241,10 @@ func (vv *VectorisedView) Readers() []bytes.Reader {
}
return readers
}
+
+// removeFirst panics when len(vv.views) < 1.
+func (vv *VectorisedView) removeFirst() {
+ vv.size -= len(vv.views[0])
+ vv.views[0] = nil
+ vv.views = vv.views[1:]
+}
diff --git a/pkg/tcpip/link/loopback/loopback.go b/pkg/tcpip/link/loopback/loopback.go
index 1e2255bfa..073c84ef9 100644
--- a/pkg/tcpip/link/loopback/loopback.go
+++ b/pkg/tcpip/link/loopback/loopback.go
@@ -98,13 +98,13 @@ func (e *endpoint) WritePackets(*stack.Route, *stack.GSO, stack.PacketBufferList
// WriteRawPacket implements stack.LinkEndpoint.WriteRawPacket.
func (e *endpoint) WriteRawPacket(vv buffer.VectorisedView) *tcpip.Error {
- // Reject the packet if it's shorter than an ethernet header.
- if vv.Size() < header.EthernetMinimumSize {
+ // There should be an ethernet header at the beginning of vv.
+ hdr, ok := vv.PullUp(header.EthernetMinimumSize)
+ if !ok {
+ // Reject the packet if it's shorter than an ethernet header.
return tcpip.ErrBadAddress
}
-
- // There should be an ethernet header at the beginning of vv.
- linkHeader := header.Ethernet(vv.First()[:header.EthernetMinimumSize])
+ linkHeader := header.Ethernet(hdr)
vv.TrimFront(len(linkHeader))
e.dispatcher.DeliverNetworkPacket(e, "" /* remote */, "" /* local */, linkHeader.Type(), stack.PacketBuffer{
Data: vv,
diff --git a/pkg/tcpip/link/sniffer/sniffer.go b/pkg/tcpip/link/sniffer/sniffer.go
index be2537a82..0799c8f4d 100644
--- a/pkg/tcpip/link/sniffer/sniffer.go
+++ b/pkg/tcpip/link/sniffer/sniffer.go
@@ -171,11 +171,7 @@ func (e *endpoint) GSOMaxSize() uint32 {
func (e *endpoint) dumpPacket(prefix string, gso *stack.GSO, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer) {
writer := e.writer
if writer == nil && atomic.LoadUint32(&LogPackets) == 1 {
- first := pkt.Header.View()
- if len(first) == 0 {
- first = pkt.Data.First()
- }
- logPacket(prefix, protocol, first, gso)
+ logPacket(prefix, protocol, pkt, gso)
}
if writer != nil && atomic.LoadUint32(&LogPacketsToPCAP) == 1 {
totalLength := pkt.Header.UsedLength() + pkt.Data.Size()
@@ -238,7 +234,7 @@ func (e *endpoint) WriteRawPacket(vv buffer.VectorisedView) *tcpip.Error {
// Wait implements stack.LinkEndpoint.Wait.
func (e *endpoint) Wait() { e.lower.Wait() }
-func logPacket(prefix string, protocol tcpip.NetworkProtocolNumber, b buffer.View, gso *stack.GSO) {
+func logPacket(prefix string, protocol tcpip.NetworkProtocolNumber, pkt *stack.PacketBuffer, gso *stack.GSO) {
// Figure out the network layer info.
var transProto uint8
src := tcpip.Address("unknown")
@@ -247,28 +243,49 @@ func logPacket(prefix string, protocol tcpip.NetworkProtocolNumber, b buffer.Vie
size := uint16(0)
var fragmentOffset uint16
var moreFragments bool
+
+ // Create a clone of pkt, including any headers if present. Avoid allocating
+ // backing memory for the clone.
+ views := [8]buffer.View{}
+ vv := buffer.NewVectorisedView(0, views[:0])
+ vv.AppendView(pkt.Header.View())
+ vv.Append(pkt.Data)
+
switch protocol {
case header.IPv4ProtocolNumber:
- ipv4 := header.IPv4(b)
+ hdr, ok := vv.PullUp(header.IPv4MinimumSize)
+ if !ok {
+ return
+ }
+ ipv4 := header.IPv4(hdr)
fragmentOffset = ipv4.FragmentOffset()
moreFragments = ipv4.Flags()&header.IPv4FlagMoreFragments == header.IPv4FlagMoreFragments
src = ipv4.SourceAddress()
dst = ipv4.DestinationAddress()
transProto = ipv4.Protocol()
size = ipv4.TotalLength() - uint16(ipv4.HeaderLength())
- b = b[ipv4.HeaderLength():]
+ vv.TrimFront(int(ipv4.HeaderLength()))
id = int(ipv4.ID())
case header.IPv6ProtocolNumber:
- ipv6 := header.IPv6(b)
+ hdr, ok := vv.PullUp(header.IPv6MinimumSize)
+ if !ok {
+ return
+ }
+ ipv6 := header.IPv6(hdr)
src = ipv6.SourceAddress()
dst = ipv6.DestinationAddress()
transProto = ipv6.NextHeader()
size = ipv6.PayloadLength()
- b = b[header.IPv6MinimumSize:]
+ vv.TrimFront(header.IPv6MinimumSize)
case header.ARPProtocolNumber:
- arp := header.ARP(b)
+ hdr, ok := vv.PullUp(header.ARPSize)
+ if !ok {
+ return
+ }
+ vv.TrimFront(header.ARPSize)
+ arp := header.ARP(hdr)
log.Infof(
"%s arp %v (%v) -> %v (%v) valid:%v",
prefix,
@@ -284,7 +301,7 @@ func logPacket(prefix string, protocol tcpip.NetworkProtocolNumber, b buffer.Vie
// We aren't guaranteed to have a transport header - it's possible for
// writes via raw endpoints to contain only network headers.
- if minSize, ok := transportProtocolMinSizes[tcpip.TransportProtocolNumber(transProto)]; ok && len(b) < minSize {
+ if minSize, ok := transportProtocolMinSizes[tcpip.TransportProtocolNumber(transProto)]; ok && vv.Size() < minSize {
log.Infof("%s %v -> %v transport protocol: %d, but no transport header found (possible raw packet)", prefix, src, dst, transProto)
return
}
@@ -297,7 +314,11 @@ func logPacket(prefix string, protocol tcpip.NetworkProtocolNumber, b buffer.Vie
switch tcpip.TransportProtocolNumber(transProto) {
case header.ICMPv4ProtocolNumber:
transName = "icmp"
- icmp := header.ICMPv4(b)
+ hdr, ok := vv.PullUp(header.ICMPv4MinimumSize)
+ if !ok {
+ break
+ }
+ icmp := header.ICMPv4(hdr)
icmpType := "unknown"
if fragmentOffset == 0 {
switch icmp.Type() {
@@ -330,7 +351,11 @@ func logPacket(prefix string, protocol tcpip.NetworkProtocolNumber, b buffer.Vie
case header.ICMPv6ProtocolNumber:
transName = "icmp"
- icmp := header.ICMPv6(b)
+ hdr, ok := vv.PullUp(header.ICMPv6MinimumSize)
+ if !ok {
+ break
+ }
+ icmp := header.ICMPv6(hdr)
icmpType := "unknown"
switch icmp.Type() {
case header.ICMPv6DstUnreachable:
@@ -361,7 +386,11 @@ func logPacket(prefix string, protocol tcpip.NetworkProtocolNumber, b buffer.Vie
case header.UDPProtocolNumber:
transName = "udp"
- udp := header.UDP(b)
+ hdr, ok := vv.PullUp(header.UDPMinimumSize)
+ if !ok {
+ break
+ }
+ udp := header.UDP(hdr)
if fragmentOffset == 0 && len(udp) >= header.UDPMinimumSize {
srcPort = udp.SourcePort()
dstPort = udp.DestinationPort()
@@ -371,7 +400,11 @@ func logPacket(prefix string, protocol tcpip.NetworkProtocolNumber, b buffer.Vie
case header.TCPProtocolNumber:
transName = "tcp"
- tcp := header.TCP(b)
+ hdr, ok := vv.PullUp(header.TCPMinimumSize)
+ if !ok {
+ break
+ }
+ tcp := header.TCP(hdr)
if fragmentOffset == 0 && len(tcp) >= header.TCPMinimumSize {
offset := int(tcp.DataOffset())
if offset < header.TCPMinimumSize {
diff --git a/pkg/tcpip/network/arp/arp.go b/pkg/tcpip/network/arp/arp.go
index 7acbfa0a8..cf73a939e 100644
--- a/pkg/tcpip/network/arp/arp.go
+++ b/pkg/tcpip/network/arp/arp.go
@@ -93,7 +93,10 @@ func (e *endpoint) WriteHeaderIncludedPacket(r *stack.Route, pkt stack.PacketBuf
}
func (e *endpoint) HandlePacket(r *stack.Route, pkt stack.PacketBuffer) {
- v := pkt.Data.First()
+ v, ok := pkt.Data.PullUp(header.ARPSize)
+ if !ok {
+ return
+ }
h := header.ARP(v)
if !h.IsValid() {
return
diff --git a/pkg/tcpip/network/ipv4/icmp.go b/pkg/tcpip/network/ipv4/icmp.go
index c4bf1ba5c..4cbefe5ab 100644
--- a/pkg/tcpip/network/ipv4/icmp.go
+++ b/pkg/tcpip/network/ipv4/icmp.go
@@ -25,7 +25,11 @@ import (
// used to find out which transport endpoint must be notified about the ICMP
// packet.
func (e *endpoint) handleControl(typ stack.ControlType, extra uint32, pkt stack.PacketBuffer) {
- h := header.IPv4(pkt.Data.First())
+ h, ok := pkt.Data.PullUp(header.IPv4MinimumSize)
+ if !ok {
+ return
+ }
+ hdr := header.IPv4(h)
// We don't use IsValid() here because ICMP only requires that the IP
// header plus 8 bytes of the transport header be included. So it's
@@ -34,12 +38,12 @@ func (e *endpoint) handleControl(typ stack.ControlType, extra uint32, pkt stack.
//
// Drop packet if it doesn't have the basic IPv4 header or if the
// original source address doesn't match the endpoint's address.
- if len(h) < header.IPv4MinimumSize || h.SourceAddress() != e.id.LocalAddress {
+ if hdr.SourceAddress() != e.id.LocalAddress {
return
}
- hlen := int(h.HeaderLength())
- if pkt.Data.Size() < hlen || h.FragmentOffset() != 0 {
+ hlen := int(hdr.HeaderLength())
+ if pkt.Data.Size() < hlen || hdr.FragmentOffset() != 0 {
// We won't be able to handle this if it doesn't contain the
// full IPv4 header, or if it's a fragment not at offset 0
// (because it won't have the transport header).
@@ -48,15 +52,15 @@ func (e *endpoint) handleControl(typ stack.ControlType, extra uint32, pkt stack.
// Skip the ip header, then deliver control message.
pkt.Data.TrimFront(hlen)
- p := h.TransportProtocol()
- e.dispatcher.DeliverTransportControlPacket(e.id.LocalAddress, h.DestinationAddress(), ProtocolNumber, p, typ, extra, pkt)
+ p := hdr.TransportProtocol()
+ e.dispatcher.DeliverTransportControlPacket(e.id.LocalAddress, hdr.DestinationAddress(), ProtocolNumber, p, typ, extra, pkt)
}
func (e *endpoint) handleICMP(r *stack.Route, pkt stack.PacketBuffer) {
stats := r.Stats()
received := stats.ICMP.V4PacketsReceived
- v := pkt.Data.First()
- if len(v) < header.ICMPv4MinimumSize {
+ v, ok := pkt.Data.PullUp(header.ICMPv4MinimumSize)
+ if !ok {
received.Invalid.Increment()
return
}
diff --git a/pkg/tcpip/network/ipv4/ipv4.go b/pkg/tcpip/network/ipv4/ipv4.go
index 104aafbed..17202cc7a 100644
--- a/pkg/tcpip/network/ipv4/ipv4.go
+++ b/pkg/tcpip/network/ipv4/ipv4.go
@@ -328,7 +328,11 @@ func (e *endpoint) WritePackets(r *stack.Route, gso *stack.GSO, pkts stack.Packe
func (e *endpoint) WriteHeaderIncludedPacket(r *stack.Route, pkt stack.PacketBuffer) *tcpip.Error {
// The packet already has an IP header, but there are a few required
// checks.
- ip := header.IPv4(pkt.Data.First())
+ h, ok := pkt.Data.PullUp(header.IPv4MinimumSize)
+ if !ok {
+ return tcpip.ErrInvalidOptionValue
+ }
+ ip := header.IPv4(h)
if !ip.IsValid(pkt.Data.Size()) {
return tcpip.ErrInvalidOptionValue
}
@@ -378,7 +382,11 @@ func (e *endpoint) WriteHeaderIncludedPacket(r *stack.Route, pkt stack.PacketBuf
// HandlePacket is called by the link layer when new ipv4 packets arrive for
// this endpoint.
func (e *endpoint) HandlePacket(r *stack.Route, pkt stack.PacketBuffer) {
- headerView := pkt.Data.First()
+ headerView, ok := pkt.Data.PullUp(header.IPv4MinimumSize)
+ if !ok {
+ r.Stats().IP.MalformedPacketsReceived.Increment()
+ return
+ }
h := header.IPv4(headerView)
if !h.IsValid(pkt.Data.Size()) {
r.Stats().IP.MalformedPacketsReceived.Increment()
diff --git a/pkg/tcpip/network/ipv6/icmp.go b/pkg/tcpip/network/ipv6/icmp.go
index b68983d10..bdf3a0d25 100644
--- a/pkg/tcpip/network/ipv6/icmp.go
+++ b/pkg/tcpip/network/ipv6/icmp.go
@@ -28,7 +28,11 @@ import (
// used to find out which transport endpoint must be notified about the ICMP
// packet.
func (e *endpoint) handleControl(typ stack.ControlType, extra uint32, pkt stack.PacketBuffer) {
- h := header.IPv6(pkt.Data.First())
+ h, ok := pkt.Data.PullUp(header.IPv6MinimumSize)
+ if !ok {
+ return
+ }
+ hdr := header.IPv6(h)
// We don't use IsValid() here because ICMP only requires that up to
// 1280 bytes of the original packet be included. So it's likely that it
@@ -36,17 +40,21 @@ func (e *endpoint) handleControl(typ stack.ControlType, extra uint32, pkt stack.
//
// Drop packet if it doesn't have the basic IPv6 header or if the
// original source address doesn't match the endpoint's address.
- if len(h) < header.IPv6MinimumSize || h.SourceAddress() != e.id.LocalAddress {
+ if hdr.SourceAddress() != e.id.LocalAddress {
return
}
// Skip the IP header, then handle the fragmentation header if there
// is one.
pkt.Data.TrimFront(header.IPv6MinimumSize)
- p := h.TransportProtocol()
+ p := hdr.TransportProtocol()
if p == header.IPv6FragmentHeader {
- f := header.IPv6Fragment(pkt.Data.First())
- if !f.IsValid() || f.FragmentOffset() != 0 {
+ f, ok := pkt.Data.PullUp(header.IPv6FragmentHeaderSize)
+ if !ok {
+ return
+ }
+ fragHdr := header.IPv6Fragment(f)
+ if !fragHdr.IsValid() || fragHdr.FragmentOffset() != 0 {
// We can't handle fragments that aren't at offset 0
// because they don't have the transport headers.
return
@@ -55,19 +63,19 @@ func (e *endpoint) handleControl(typ stack.ControlType, extra uint32, pkt stack.
// Skip fragmentation header and find out the actual protocol
// number.
pkt.Data.TrimFront(header.IPv6FragmentHeaderSize)
- p = f.TransportProtocol()
+ p = fragHdr.TransportProtocol()
}
// Deliver the control packet to the transport endpoint.
- e.dispatcher.DeliverTransportControlPacket(e.id.LocalAddress, h.DestinationAddress(), ProtocolNumber, p, typ, extra, pkt)
+ e.dispatcher.DeliverTransportControlPacket(e.id.LocalAddress, hdr.DestinationAddress(), ProtocolNumber, p, typ, extra, pkt)
}
func (e *endpoint) handleICMP(r *stack.Route, netHeader buffer.View, pkt stack.PacketBuffer, hasFragmentHeader bool) {
stats := r.Stats().ICMP
sent := stats.V6PacketsSent
received := stats.V6PacketsReceived
- v := pkt.Data.First()
- if len(v) < header.ICMPv6MinimumSize {
+ v, ok := pkt.Data.PullUp(header.ICMPv6HeaderSize)
+ if !ok {
received.Invalid.Increment()
return
}
@@ -76,11 +84,9 @@ func (e *endpoint) handleICMP(r *stack.Route, netHeader buffer.View, pkt stack.P
// Validate ICMPv6 checksum before processing the packet.
//
- // Only the first view in vv is accounted for by h. To account for the
- // rest of vv, a shallow copy is made and the first view is removed.
// This copy is used as extra payload during the checksum calculation.
payload := pkt.Data.Clone(nil)
- payload.RemoveFirst()
+ payload.TrimFront(len(h))
if got, want := h.Checksum(), header.ICMPv6Checksum(h, iph.SourceAddress(), iph.DestinationAddress(), payload); got != want {
received.Invalid.Increment()
return
@@ -101,34 +107,40 @@ func (e *endpoint) handleICMP(r *stack.Route, netHeader buffer.View, pkt stack.P
switch h.Type() {
case header.ICMPv6PacketTooBig:
received.PacketTooBig.Increment()
- if len(v) < header.ICMPv6PacketTooBigMinimumSize {
+ hdr, ok := pkt.Data.PullUp(header.ICMPv6PacketTooBigMinimumSize)
+ if !ok {
received.Invalid.Increment()
return
}
pkt.Data.TrimFront(header.ICMPv6PacketTooBigMinimumSize)
- mtu := h.MTU()
+ mtu := header.ICMPv6(hdr).MTU()
e.handleControl(stack.ControlPacketTooBig, calculateMTU(mtu), pkt)
case header.ICMPv6DstUnreachable:
received.DstUnreachable.Increment()
- if len(v) < header.ICMPv6DstUnreachableMinimumSize {
+ hdr, ok := pkt.Data.PullUp(header.ICMPv6DstUnreachableMinimumSize)
+ if !ok {
received.Invalid.Increment()
return
}
pkt.Data.TrimFront(header.ICMPv6DstUnreachableMinimumSize)
- switch h.Code() {
+ switch header.ICMPv6(hdr).Code() {
case header.ICMPv6PortUnreachable:
e.handleControl(stack.ControlPortUnreachable, 0, pkt)
}
case header.ICMPv6NeighborSolicit:
received.NeighborSolicit.Increment()
- if len(v) < header.ICMPv6NeighborSolicitMinimumSize || !isNDPValid() {
+ if pkt.Data.Size() < header.ICMPv6NeighborSolicitMinimumSize || !isNDPValid() {
received.Invalid.Increment()
return
}
- ns := header.NDPNeighborSolicit(h.NDPPayload())
+ // The remainder of payload must be only the neighbor solicitation, so
+ // payload.ToView() always returns the solicitation. Per RFC 6980 section 5,
+ // NDP messages cannot be fragmented. Also note that in the common case NDP
+ // datagrams are very small and ToView() will not incur allocations.
+ ns := header.NDPNeighborSolicit(payload.ToView())
it, err := ns.Options().Iter(true)
if err != nil {
// If we have a malformed NDP NS option, drop the packet.
@@ -286,12 +298,16 @@ func (e *endpoint) handleICMP(r *stack.Route, netHeader buffer.View, pkt stack.P
case header.ICMPv6NeighborAdvert:
received.NeighborAdvert.Increment()
- if len(v) < header.ICMPv6NeighborAdvertSize || !isNDPValid() {
+ if pkt.Data.Size() < header.ICMPv6NeighborAdvertSize || !isNDPValid() {
received.Invalid.Increment()
return
}
- na := header.NDPNeighborAdvert(h.NDPPayload())
+ // The remainder of payload must be only the neighbor advertisement, so
+ // payload.ToView() always returns the advertisement. Per RFC 6980 section
+ // 5, NDP messages cannot be fragmented. Also note that in the common case
+ // NDP datagrams are very small and ToView() will not incur allocations.
+ na := header.NDPNeighborAdvert(payload.ToView())
it, err := na.Options().Iter(true)
if err != nil {
// If we have a malformed NDP NA option, drop the packet.
@@ -363,14 +379,15 @@ func (e *endpoint) handleICMP(r *stack.Route, netHeader buffer.View, pkt stack.P
case header.ICMPv6EchoRequest:
received.EchoRequest.Increment()
- if len(v) < header.ICMPv6EchoMinimumSize {
+ icmpHdr, ok := pkt.Data.PullUp(header.ICMPv6EchoMinimumSize)
+ if !ok {
received.Invalid.Increment()
return
}
pkt.Data.TrimFront(header.ICMPv6EchoMinimumSize)
hdr := buffer.NewPrependable(int(r.MaxHeaderLength()) + header.ICMPv6EchoMinimumSize)
packet := header.ICMPv6(hdr.Prepend(header.ICMPv6EchoMinimumSize))
- copy(packet, h)
+ copy(packet, icmpHdr)
packet.SetType(header.ICMPv6EchoReply)
packet.SetChecksum(header.ICMPv6Checksum(packet, r.LocalAddress, r.RemoteAddress, pkt.Data))
if err := r.WritePacket(nil /* gso */, stack.NetworkHeaderParams{Protocol: header.ICMPv6ProtocolNumber, TTL: r.DefaultTTL(), TOS: stack.DefaultTOS}, stack.PacketBuffer{
@@ -384,7 +401,7 @@ func (e *endpoint) handleICMP(r *stack.Route, netHeader buffer.View, pkt stack.P
case header.ICMPv6EchoReply:
received.EchoReply.Increment()
- if len(v) < header.ICMPv6EchoMinimumSize {
+ if pkt.Data.Size() < header.ICMPv6EchoMinimumSize {
received.Invalid.Increment()
return
}
@@ -406,8 +423,9 @@ func (e *endpoint) handleICMP(r *stack.Route, netHeader buffer.View, pkt stack.P
case header.ICMPv6RouterAdvert:
received.RouterAdvert.Increment()
- p := h.NDPPayload()
- if len(p) < header.NDPRAMinimumSize || !isNDPValid() {
+ // Is the NDP payload of sufficient size to hold a Router
+ // Advertisement?
+ if pkt.Data.Size()-header.ICMPv6HeaderSize < header.NDPRAMinimumSize || !isNDPValid() {
received.Invalid.Increment()
return
}
@@ -425,7 +443,11 @@ func (e *endpoint) handleICMP(r *stack.Route, netHeader buffer.View, pkt stack.P
return
}
- ra := header.NDPRouterAdvert(p)
+ // The remainder of payload must be only the router advertisement, so
+ // payload.ToView() always returns the advertisement. Per RFC 6980 section
+ // 5, NDP messages cannot be fragmented. Also note that in the common case
+ // NDP datagrams are very small and ToView() will not incur allocations.
+ ra := header.NDPRouterAdvert(payload.ToView())
opts := ra.Options()
// Are options valid as per the wire format?
diff --git a/pkg/tcpip/network/ipv6/ipv6.go b/pkg/tcpip/network/ipv6/ipv6.go
index 331b0817b..486725131 100644
--- a/pkg/tcpip/network/ipv6/ipv6.go
+++ b/pkg/tcpip/network/ipv6/ipv6.go
@@ -171,7 +171,11 @@ func (*endpoint) WriteHeaderIncludedPacket(r *stack.Route, pkt stack.PacketBuffe
// HandlePacket is called by the link layer when new ipv6 packets arrive for
// this endpoint.
func (e *endpoint) HandlePacket(r *stack.Route, pkt stack.PacketBuffer) {
- headerView := pkt.Data.First()
+ headerView, ok := pkt.Data.PullUp(header.IPv6MinimumSize)
+ if !ok {
+ r.Stats().IP.MalformedPacketsReceived.Increment()
+ return
+ }
h := header.IPv6(headerView)
if !h.IsValid(pkt.Data.Size()) {
r.Stats().IP.MalformedPacketsReceived.Increment()
diff --git a/pkg/tcpip/stack/iptables.go b/pkg/tcpip/stack/iptables.go
index 6c0a4b24d..6b91159d4 100755
--- a/pkg/tcpip/stack/iptables.go
+++ b/pkg/tcpip/stack/iptables.go
@@ -212,6 +212,11 @@ func (it *IPTables) Check(hook Hook, pkt PacketBuffer) bool {
// CheckPackets runs pkts through the rules for hook and returns a map of packets that
// should not go forward.
//
+// Precondition: pkt is a IPv4 packet of at least length header.IPv4MinimumSize.
+//
+// TODO(gvisor.dev/issue/170): pk.NetworkHeader will always be set as a
+// precondition.
+//
// NOTE: unlike the Check API the returned map contains packets that should be
// dropped.
func (it *IPTables) CheckPackets(hook Hook, pkts PacketBufferList) (drop map[*PacketBuffer]struct{}) {
@@ -226,7 +231,9 @@ func (it *IPTables) CheckPackets(hook Hook, pkts PacketBufferList) (drop map[*Pa
return drop
}
-// Precondition: pkt.NetworkHeader is set.
+// Precondition: pkt is a IPv4 packet of at least length header.IPv4MinimumSize.
+// TODO(gvisor.dev/issue/170): pk.NetworkHeader will always be set as a
+// precondition.
func (it *IPTables) checkChain(hook Hook, pkt PacketBuffer, table Table, ruleIdx int) chainVerdict {
// Start from ruleIdx and walk the list of rules until a rule gives us
// a verdict.
@@ -271,14 +278,21 @@ func (it *IPTables) checkChain(hook Hook, pkt PacketBuffer, table Table, ruleIdx
return chainDrop
}
-// Precondition: pk.NetworkHeader is set.
+// Precondition: pkt is a IPv4 packet of at least length header.IPv4MinimumSize.
+// TODO(gvisor.dev/issue/170): pk.NetworkHeader will always be set as a
+// precondition.
func (it *IPTables) checkRule(hook Hook, pkt PacketBuffer, table Table, ruleIdx int) (RuleVerdict, int) {
rule := table.Rules[ruleIdx]
// If pkt.NetworkHeader hasn't been set yet, it will be contained in
- // pkt.Data.First().
+ // pkt.Data.
if pkt.NetworkHeader == nil {
- pkt.NetworkHeader = pkt.Data.First()
+ var ok bool
+ pkt.NetworkHeader, ok = pkt.Data.PullUp(header.IPv4MinimumSize)
+ if !ok {
+ // Precondition has been violated.
+ panic(fmt.Sprintf("iptables checks require IPv4 headers of at least %d bytes", header.IPv4MinimumSize))
+ }
}
// Check whether the packet matches the IP header filter.
diff --git a/pkg/tcpip/stack/iptables_targets.go b/pkg/tcpip/stack/iptables_targets.go
index 7b4543caf..8be61f4b1 100755
--- a/pkg/tcpip/stack/iptables_targets.go
+++ b/pkg/tcpip/stack/iptables_targets.go
@@ -96,9 +96,12 @@ func (rt RedirectTarget) Action(pkt PacketBuffer) (RuleVerdict, int) {
newPkt := pkt.Clone()
// Set network header.
- headerView := newPkt.Data.First()
+ headerView, ok := newPkt.Data.PullUp(header.IPv4MinimumSize)
+ if !ok {
+ return RuleDrop, 0
+ }
netHeader := header.IPv4(headerView)
- newPkt.NetworkHeader = headerView[:header.IPv4MinimumSize]
+ newPkt.NetworkHeader = headerView
hlen := int(netHeader.HeaderLength())
tlen := int(netHeader.TotalLength())
@@ -117,10 +120,14 @@ func (rt RedirectTarget) Action(pkt PacketBuffer) (RuleVerdict, int) {
if newPkt.TransportHeader != nil {
udpHeader = header.UDP(newPkt.TransportHeader)
} else {
- if len(pkt.Data.First()) < header.UDPMinimumSize {
+ if pkt.Data.Size() < header.UDPMinimumSize {
+ return RuleDrop, 0
+ }
+ hdr, ok := newPkt.Data.PullUp(header.UDPMinimumSize)
+ if !ok {
return RuleDrop, 0
}
- udpHeader = header.UDP(newPkt.Data.First())
+ udpHeader = header.UDP(hdr)
}
udpHeader.SetDestinationPort(rt.MinPort)
case header.TCPProtocolNumber:
@@ -128,10 +135,14 @@ func (rt RedirectTarget) Action(pkt PacketBuffer) (RuleVerdict, int) {
if newPkt.TransportHeader != nil {
tcpHeader = header.TCP(newPkt.TransportHeader)
} else {
- if len(pkt.Data.First()) < header.TCPMinimumSize {
+ if pkt.Data.Size() < header.TCPMinimumSize {
return RuleDrop, 0
}
- tcpHeader = header.TCP(newPkt.TransportHeader)
+ hdr, ok := newPkt.Data.PullUp(header.TCPMinimumSize)
+ if !ok {
+ return RuleDrop, 0
+ }
+ tcpHeader = header.TCP(hdr)
}
// TODO(gvisor.dev/issue/170): Need to recompute checksum
// and implement nat connection tracking to support TCP.
diff --git a/pkg/tcpip/stack/nic.go b/pkg/tcpip/stack/nic.go
index 016dbe15e..0c2b1f36a 100644
--- a/pkg/tcpip/stack/nic.go
+++ b/pkg/tcpip/stack/nic.go
@@ -1203,12 +1203,12 @@ func (n *NIC) DeliverNetworkPacket(linkEP LinkEndpoint, remote, local tcpip.Link
n.stack.stats.IP.PacketsReceived.Increment()
}
- if len(pkt.Data.First()) < netProto.MinimumPacketSize() {
+ netHeader, ok := pkt.Data.PullUp(netProto.MinimumPacketSize())
+ if !ok {
n.stack.stats.MalformedRcvdPackets.Increment()
return
}
-
- src, dst := netProto.ParseAddresses(pkt.Data.First())
+ src, dst := netProto.ParseAddresses(netHeader)
if n.stack.handleLocal && !n.isLoopback() && n.getRef(protocol, src) != nil {
// The source address is one of our own, so we never should have gotten a
@@ -1289,22 +1289,8 @@ func (n *NIC) DeliverNetworkPacket(linkEP LinkEndpoint, remote, local tcpip.Link
func (n *NIC) forwardPacket(r *Route, protocol tcpip.NetworkProtocolNumber, pkt PacketBuffer) {
// TODO(b/143425874) Decrease the TTL field in forwarded packets.
-
- firstData := pkt.Data.First()
- pkt.Data.RemoveFirst()
-
- if linkHeaderLen := int(n.linkEP.MaxHeaderLength()); linkHeaderLen == 0 {
- pkt.Header = buffer.NewPrependableFromView(firstData)
- } else {
- firstDataLen := len(firstData)
-
- // pkt.Header should have enough capacity to hold n.linkEP's headers.
- pkt.Header = buffer.NewPrependable(firstDataLen + linkHeaderLen)
-
- // TODO(b/151227689): avoid copying the packet when forwarding
- if n := copy(pkt.Header.Prepend(firstDataLen), firstData); n != firstDataLen {
- panic(fmt.Sprintf("copied %d bytes, expected %d", n, firstDataLen))
- }
+ if linkHeaderLen := int(n.linkEP.MaxHeaderLength()); linkHeaderLen != 0 {
+ pkt.Header = buffer.NewPrependable(linkHeaderLen)
}
if err := n.linkEP.WritePacket(r, nil /* gso */, protocol, pkt); err != nil {
@@ -1332,12 +1318,13 @@ func (n *NIC) DeliverTransportPacket(r *Route, protocol tcpip.TransportProtocolN
// validly formed.
n.stack.demux.deliverRawPacket(r, protocol, pkt)
- if len(pkt.Data.First()) < transProto.MinimumPacketSize() {
+ transHeader, ok := pkt.Data.PullUp(transProto.MinimumPacketSize())
+ if !ok {
n.stack.stats.MalformedRcvdPackets.Increment()
return
}
- srcPort, dstPort, err := transProto.ParsePorts(pkt.Data.First())
+ srcPort, dstPort, err := transProto.ParsePorts(transHeader)
if err != nil {
n.stack.stats.MalformedRcvdPackets.Increment()
return
@@ -1375,11 +1362,12 @@ func (n *NIC) DeliverTransportControlPacket(local, remote tcpip.Address, net tcp
// ICMPv4 only guarantees that 8 bytes of the transport protocol will
// be present in the payload. We know that the ports are within the
// first 8 bytes for all known transport protocols.
- if len(pkt.Data.First()) < 8 {
+ transHeader, ok := pkt.Data.PullUp(8)
+ if !ok {
return
}
- srcPort, dstPort, err := transProto.ParsePorts(pkt.Data.First())
+ srcPort, dstPort, err := transProto.ParsePorts(transHeader)
if err != nil {
return
}
diff --git a/pkg/tcpip/stack/packet_buffer.go b/pkg/tcpip/stack/packet_buffer.go
index dc125f25e..e954a8b7e 100755
--- a/pkg/tcpip/stack/packet_buffer.go
+++ b/pkg/tcpip/stack/packet_buffer.go
@@ -37,7 +37,9 @@ type PacketBuffer struct {
Data buffer.VectorisedView
// Header holds the headers of outbound packets. As a packet is passed
- // down the stack, each layer adds to Header.
+ // down the stack, each layer adds to Header. Note that forwarded
+ // packets don't populate Headers on their way out -- their headers and
+ // payload are never parsed out and remain in Data.
Header buffer.Prependable
// These fields are used by both inbound and outbound packets. They
diff --git a/pkg/tcpip/transport/icmp/endpoint.go b/pkg/tcpip/transport/icmp/endpoint.go
index feef8dca0..b1d820372 100644
--- a/pkg/tcpip/transport/icmp/endpoint.go
+++ b/pkg/tcpip/transport/icmp/endpoint.go
@@ -747,15 +747,15 @@ func (e *endpoint) HandlePacket(r *stack.Route, id stack.TransportEndpointID, pk
// Only accept echo replies.
switch e.NetProto {
case header.IPv4ProtocolNumber:
- h := header.ICMPv4(pkt.Data.First())
- if h.Type() != header.ICMPv4EchoReply {
+ h, ok := pkt.Data.PullUp(header.ICMPv4MinimumSize)
+ if !ok || header.ICMPv4(h).Type() != header.ICMPv4EchoReply {
e.stack.Stats().DroppedPackets.Increment()
e.stats.ReceiveErrors.MalformedPacketsReceived.Increment()
return
}
case header.IPv6ProtocolNumber:
- h := header.ICMPv6(pkt.Data.First())
- if h.Type() != header.ICMPv6EchoReply {
+ h, ok := pkt.Data.PullUp(header.ICMPv6MinimumSize)
+ if !ok || header.ICMPv6(h).Type() != header.ICMPv6EchoReply {
e.stack.Stats().DroppedPackets.Increment()
e.stats.ReceiveErrors.MalformedPacketsReceived.Increment()
return
diff --git a/pkg/tcpip/transport/tcp/segment.go b/pkg/tcpip/transport/tcp/segment.go
index 40461fd31..7712ce652 100644
--- a/pkg/tcpip/transport/tcp/segment.go
+++ b/pkg/tcpip/transport/tcp/segment.go
@@ -144,7 +144,11 @@ func (s *segment) logicalLen() seqnum.Size {
// TCP checksum and stores the checksum and result of checksum verification in
// the csum and csumValid fields of the segment.
func (s *segment) parse() bool {
- h := header.TCP(s.data.First())
+ h, ok := s.data.PullUp(header.TCPMinimumSize)
+ if !ok {
+ return false
+ }
+ hdr := header.TCP(h)
// h is the header followed by the payload. We check that the offset to
// the data respects the following constraints:
@@ -156,12 +160,16 @@ func (s *segment) parse() bool {
// N.B. The segment has already been validated as having at least the
// minimum TCP size before reaching here, so it's safe to read the
// fields.
- offset := int(h.DataOffset())
- if offset < header.TCPMinimumSize || offset > len(h) {
+ offset := int(hdr.DataOffset())
+ if offset < header.TCPMinimumSize {
+ return false
+ }
+ hdrWithOpts, ok := s.data.PullUp(offset)
+ if !ok {
return false
}
- s.options = []byte(h[header.TCPMinimumSize:offset])
+ s.options = []byte(hdrWithOpts[header.TCPMinimumSize:])
s.parsedOptions = header.ParseTCPOptions(s.options)
// Query the link capabilities to decide if checksum validation is
@@ -173,18 +181,19 @@ func (s *segment) parse() bool {
s.data.TrimFront(offset)
}
if verifyChecksum {
- s.csum = h.Checksum()
+ hdr = header.TCP(hdrWithOpts)
+ s.csum = hdr.Checksum()
xsum := s.route.PseudoHeaderChecksum(ProtocolNumber, uint16(s.data.Size()))
- xsum = h.CalculateChecksum(xsum)
+ xsum = hdr.CalculateChecksum(xsum)
s.data.TrimFront(offset)
xsum = header.ChecksumVV(s.data, xsum)
s.csumValid = xsum == 0xffff
}
- s.sequenceNumber = seqnum.Value(h.SequenceNumber())
- s.ackNumber = seqnum.Value(h.AckNumber())
- s.flags = h.Flags()
- s.window = seqnum.Size(h.WindowSize())
+ s.sequenceNumber = seqnum.Value(hdr.SequenceNumber())
+ s.ackNumber = seqnum.Value(hdr.AckNumber())
+ s.flags = hdr.Flags()
+ s.window = seqnum.Size(hdr.WindowSize())
return true
}
diff --git a/pkg/tcpip/transport/udp/endpoint.go b/pkg/tcpip/transport/udp/endpoint.go
index edb54f0be..756ab913a 100644
--- a/pkg/tcpip/transport/udp/endpoint.go
+++ b/pkg/tcpip/transport/udp/endpoint.go
@@ -1250,8 +1250,8 @@ func (e *endpoint) Readiness(mask waiter.EventMask) waiter.EventMask {
// endpoint.
func (e *endpoint) HandlePacket(r *stack.Route, id stack.TransportEndpointID, pkt stack.PacketBuffer) {
// Get the header then trim it from the view.
- hdr := header.UDP(pkt.Data.First())
- if int(hdr.Length()) > pkt.Data.Size() {
+ hdr, ok := pkt.Data.PullUp(header.UDPMinimumSize)
+ if !ok || int(header.UDP(hdr).Length()) > pkt.Data.Size() {
// Malformed packet.
e.stack.Stats().UDP.MalformedPacketsReceived.Increment()
e.stats.ReceiveErrors.MalformedPacketsReceived.Increment()
@@ -1286,7 +1286,7 @@ func (e *endpoint) HandlePacket(r *stack.Route, id stack.TransportEndpointID, pk
senderAddress: tcpip.FullAddress{
NIC: r.NICID(),
Addr: id.RemoteAddress,
- Port: hdr.SourcePort(),
+ Port: header.UDP(hdr).SourcePort(),
},
}
packet.data = pkt.Data
diff --git a/pkg/tcpip/transport/udp/protocol.go b/pkg/tcpip/transport/udp/protocol.go
index 6e31a9bac..52af6de22 100644
--- a/pkg/tcpip/transport/udp/protocol.go
+++ b/pkg/tcpip/transport/udp/protocol.go
@@ -68,8 +68,13 @@ func (*protocol) ParsePorts(v buffer.View) (src, dst uint16, err *tcpip.Error) {
// that don't match any existing endpoint.
func (p *protocol) HandleUnknownDestinationPacket(r *stack.Route, id stack.TransportEndpointID, pkt stack.PacketBuffer) bool {
// Get the header then trim it from the view.
- hdr := header.UDP(pkt.Data.First())
- if int(hdr.Length()) > pkt.Data.Size() {
+ h, ok := pkt.Data.PullUp(header.UDPMinimumSize)
+ if !ok {
+ // Malformed packet.
+ r.Stack().Stats().UDP.MalformedPacketsReceived.Increment()
+ return true
+ }
+ if int(header.UDP(h).Length()) > pkt.Data.Size() {
// Malformed packet.
r.Stack().Stats().UDP.MalformedPacketsReceived.Increment()
return true
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-14 22:21:33 +0000