Merge release-20200622.1-33-g8dbeac53c (automated)

2 files changed, 45 insertions, 26 deletions

diff --git a/pkg/tcpip/transport/udp/endpoint.go b/pkg/tcpip/transport/udp/endpoint.go
index 8bdc1ee1f..cae29fbff 100644
--- a/pkg/tcpip/transport/udp/endpoint.go
+++ b/pkg/tcpip/transport/udp/endpoint.go
@@ -109,6 +109,7 @@ type endpoint struct {
 	portFlags      ports.Flags
 	bindToDevice   tcpip.NICID
 	broadcast      bool
+	noChecksum     bool
 
 	lastErrorMu sync.Mutex   `state:"nosave"`
 	lastError   *tcpip.Error `state:".(string)"`
@@ -529,7 +530,7 @@ func (e *endpoint) write(p tcpip.Payloader, opts tcpip.WriteOptions) (int64, <-c
 		useDefaultTTL = false
 	}
 
-	if err := sendUDP(route, buffer.View(v).ToVectorisedView(), e.ID.LocalPort, dstPort, ttl, useDefaultTTL, e.sendTOS, e.owner); err != nil {
+	if err := sendUDP(route, buffer.View(v).ToVectorisedView(), e.ID.LocalPort, dstPort, ttl, useDefaultTTL, e.sendTOS, e.owner, e.noChecksum); err != nil {
 		return 0, nil, err
 	}
 	return int64(len(v)), nil, nil
@@ -553,6 +554,11 @@ func (e *endpoint) SetSockOptBool(opt tcpip.SockOptBool, v bool) *tcpip.Error {
 		e.multicastLoop = v
 		e.mu.Unlock()
 
+	case tcpip.NoChecksumOption:
+		e.mu.Lock()
+		e.noChecksum = v
+		e.mu.Unlock()
+
 	case tcpip.ReceiveTOSOption:
 		e.mu.Lock()
 		e.receiveTOS = v
@@ -825,6 +831,12 @@ func (e *endpoint) GetSockOptBool(opt tcpip.SockOptBool) (bool, *tcpip.Error) {
 		e.mu.RUnlock()
 		return v, nil
 
+	case tcpip.NoChecksumOption:
+		e.mu.RLock()
+		v := e.noChecksum
+		e.mu.RUnlock()
+		return v, nil
+
 	case tcpip.ReceiveTOSOption:
 		e.mu.RLock()
 		v := e.receiveTOS
@@ -959,7 +971,7 @@ func (e *endpoint) GetSockOpt(opt interface{}) *tcpip.Error {
 
 // sendUDP sends a UDP segment via the provided network endpoint and under the
 // provided identity.
-func sendUDP(r *stack.Route, data buffer.VectorisedView, localPort, remotePort uint16, ttl uint8, useDefaultTTL bool, tos uint8, owner tcpip.PacketOwner) *tcpip.Error {
+func sendUDP(r *stack.Route, data buffer.VectorisedView, localPort, remotePort uint16, ttl uint8, useDefaultTTL bool, tos uint8, owner tcpip.PacketOwner, noChecksum bool) *tcpip.Error {
 	// Allocate a buffer for the UDP header.
 	hdr := buffer.NewPrependable(header.UDPMinimumSize + int(r.MaxHeaderLength()))
 
@@ -973,8 +985,12 @@ func sendUDP(r *stack.Route, data buffer.VectorisedView, localPort, remotePort u
 		Length:  length,
 	})
 
-	// Only calculate the checksum if offloading isn't supported.
-	if r.Capabilities()&stack.CapabilityTXChecksumOffload == 0 {
+	// Set the checksum field unless TX checksum offload is enabled.
+	// On IPv4, UDP checksum is optional, and a zero value indicates the
+	// transmitter skipped the checksum generation (RFC768).
+	// On IPv6, UDP checksum is not optional (RFC2460 Section 8.1).
+	if r.Capabilities()&stack.CapabilityTXChecksumOffload == 0 &&
+		(!noChecksum || r.NetProto == header.IPv6ProtocolNumber) {
 		xsum := r.PseudoHeaderChecksum(ProtocolNumber, length)
 		for _, v := range data.Views() {
 			xsum = header.Checksum(v, xsum)
diff --git a/pkg/tcpip/transport/udp/udp_state_autogen.go b/pkg/tcpip/transport/udp/udp_state_autogen.go
index 943022c38..50fd0f186 100644
--- a/pkg/tcpip/transport/udp/udp_state_autogen.go
+++ b/pkg/tcpip/transport/udp/udp_state_autogen.go
@@ -73,6 +73,7 @@ func (x *endpoint) StateFields() []string {
 		"portFlags",
 		"bindToDevice",
 		"broadcast",
+		"noChecksum",
 		"lastError",
 		"boundBindToDevice",
 		"boundPortFlags",
@@ -92,7 +93,7 @@ func (x *endpoint) StateSave(m state.Sink) {
 	var rcvBufSizeMax int = x.saveRcvBufSizeMax()
 	m.SaveValue(5, rcvBufSizeMax)
 	var lastError string = x.saveLastError()
-	m.SaveValue(21, lastError)
+	m.SaveValue(22, lastError)
 	m.Save(0, &x.TransportEndpointInfo)
 	m.Save(1, &x.waiterQueue)
 	m.Save(2, &x.uniqueID)
@@ -113,16 +114,17 @@ func (x *endpoint) StateSave(m state.Sink) {
 	m.Save(18, &x.portFlags)
 	m.Save(19, &x.bindToDevice)
 	m.Save(20, &x.broadcast)
-	m.Save(22, &x.boundBindToDevice)
-	m.Save(23, &x.boundPortFlags)
-	m.Save(24, &x.sendTOS)
-	m.Save(25, &x.receiveTOS)
-	m.Save(26, &x.receiveTClass)
-	m.Save(27, &x.receiveIPPacketInfo)
-	m.Save(28, &x.shutdownFlags)
-	m.Save(29, &x.multicastMemberships)
-	m.Save(30, &x.effectiveNetProtos)
-	m.Save(31, &x.owner)
+	m.Save(21, &x.noChecksum)
+	m.Save(23, &x.boundBindToDevice)
+	m.Save(24, &x.boundPortFlags)
+	m.Save(25, &x.sendTOS)
+	m.Save(26, &x.receiveTOS)
+	m.Save(27, &x.receiveTClass)
+	m.Save(28, &x.receiveIPPacketInfo)
+	m.Save(29, &x.shutdownFlags)
+	m.Save(30, &x.multicastMemberships)
+	m.Save(31, &x.effectiveNetProtos)
+	m.Save(32, &x.owner)
 }
 
 func (x *endpoint) StateLoad(m state.Source) {
@@ -146,18 +148,19 @@ func (x *endpoint) StateLoad(m state.Source) {
 	m.Load(18, &x.portFlags)
 	m.Load(19, &x.bindToDevice)
 	m.Load(20, &x.broadcast)
-	m.Load(22, &x.boundBindToDevice)
-	m.Load(23, &x.boundPortFlags)
-	m.Load(24, &x.sendTOS)
-	m.Load(25, &x.receiveTOS)
-	m.Load(26, &x.receiveTClass)
-	m.Load(27, &x.receiveIPPacketInfo)
-	m.Load(28, &x.shutdownFlags)
-	m.Load(29, &x.multicastMemberships)
-	m.Load(30, &x.effectiveNetProtos)
-	m.Load(31, &x.owner)
+	m.Load(21, &x.noChecksum)
+	m.Load(23, &x.boundBindToDevice)
+	m.Load(24, &x.boundPortFlags)
+	m.Load(25, &x.sendTOS)
+	m.Load(26, &x.receiveTOS)
+	m.Load(27, &x.receiveTClass)
+	m.Load(28, &x.receiveIPPacketInfo)
+	m.Load(29, &x.shutdownFlags)
+	m.Load(30, &x.multicastMemberships)
+	m.Load(31, &x.effectiveNetProtos)
+	m.Load(32, &x.owner)
 	m.LoadValue(5, new(int), func(y interface{}) { x.loadRcvBufSizeMax(y.(int)) })
-	m.LoadValue(21, new(string), func(y interface{}) { x.loadLastError(y.(string)) })
+	m.LoadValue(22, new(string), func(y interface{}) { x.loadLastError(y.(string)) })
 	m.AfterLoad(x.afterLoad)
 }