Clean up warnings

- Typos
- Unused arguments
- Useless conversions

PiperOrigin-RevId: 376362730

2 files changed, 29 insertions, 30 deletions

diff --git a/pkg/tcpip/network/ipv4/ipv4.go b/pkg/tcpip/network/ipv4/ipv4.go
index bb8d53c12..6bee55634 100644
--- a/pkg/tcpip/network/ipv4/ipv4.go
+++ b/pkg/tcpip/network/ipv4/ipv4.go
@@ -82,7 +82,7 @@ type endpoint struct {
 	protocol   *protocol
 	stats      sharedStats
 
-	// enabled is set to 1 when the enpoint is enabled and 0 when it is
+	// enabled is set to 1 when the endpoint is enabled and 0 when it is
 	// disabled.
 	//
 	// Must be accessed using atomic operations.
@@ -332,8 +332,8 @@ func (e *endpoint) DefaultTTL() uint8 {
 	return e.protocol.DefaultTTL()
 }
 
-// MTU implements stack.NetworkEndpoint.MTU. It returns the link-layer MTU minus
-// the network layer max header length.
+// MTU implements stack.NetworkEndpoint. It returns the link-layer MTU minus the
+// network layer max header length.
 func (e *endpoint) MTU() uint32 {
 	networkMTU, err := calculateNetworkMTU(e.nic.MTU(), header.IPv4MinimumSize)
 	if err != nil {
@@ -348,7 +348,7 @@ func (e *endpoint) MaxHeaderLength() uint16 {
 	return e.nic.MaxHeaderLength() + header.IPv4MaximumHeaderSize
 }
 
-// NetworkProtocolNumber implements stack.NetworkEndpoint.NetworkProtocolNumber.
+// NetworkProtocolNumber implements stack.NetworkEndpoint.
 func (e *endpoint) NetworkProtocolNumber() tcpip.NetworkProtocolNumber {
 	return e.protocol.Number()
 }
@@ -363,7 +363,7 @@ func (e *endpoint) addIPHeader(srcAddr, dstAddr tcpip.Address, pkt *stack.Packet
 	if hdrLen > header.IPv4MaximumHeaderSize {
 		return &tcpip.ErrMessageTooLong{}
 	}
-	ip := header.IPv4(pkt.NetworkHeader().Push(hdrLen))
+	ipH := header.IPv4(pkt.NetworkHeader().Push(hdrLen))
 	length := pkt.Size()
 	if length > math.MaxUint16 {
 		return &tcpip.ErrMessageTooLong{}
@@ -372,7 +372,7 @@ func (e *endpoint) addIPHeader(srcAddr, dstAddr tcpip.Address, pkt *stack.Packet
 	// datagrams. Since the DF bit is never being set here, all datagrams
 	// are non-atomic and need an ID.
 	id := atomic.AddUint32(&e.protocol.ids[hashRoute(srcAddr, dstAddr, params.Protocol, e.protocol.hashIV)%buckets], 1)
-	ip.Encode(&header.IPv4Fields{
+	ipH.Encode(&header.IPv4Fields{
 		TotalLength: uint16(length),
 		ID:          uint16(id),
 		TTL:         params.TTL,
@@ -382,7 +382,7 @@ func (e *endpoint) addIPHeader(srcAddr, dstAddr tcpip.Address, pkt *stack.Packet
 		DstAddr:     dstAddr,
 		Options:     options,
 	})
-	ip.SetChecksum(^ip.CalculateChecksum())
+	ipH.SetChecksum(^ipH.CalculateChecksum())
 	pkt.NetworkProtocolNumber = ProtocolNumber
 	return nil
 }
@@ -391,7 +391,7 @@ func (e *endpoint) addIPHeader(srcAddr, dstAddr tcpip.Address, pkt *stack.Packet
 // fragment. It returns the number of fragments handled and the number of
 // fragments left to be processed. The IP header must already be present in the
 // original packet.
-func (e *endpoint) handleFragments(r *stack.Route, networkMTU uint32, pkt *stack.PacketBuffer, handler func(*stack.PacketBuffer) tcpip.Error) (int, int, tcpip.Error) {
+func (e *endpoint) handleFragments(_ *stack.Route, networkMTU uint32, pkt *stack.PacketBuffer, handler func(*stack.PacketBuffer) tcpip.Error) (int, int, tcpip.Error) {
 	// Round the MTU down to align to 8 bytes.
 	fragmentPayloadSize := networkMTU &^ 7
 	networkHeader := header.IPv4(pkt.NetworkHeader().View())
@@ -500,7 +500,7 @@ func (e *endpoint) writePacket(r *stack.Route, pkt *stack.PacketBuffer, headerIn
 	return nil
 }
 
-// WritePackets implements stack.NetworkEndpoint.WritePackets.
+// WritePackets implements stack.NetworkEndpoint.
 func (e *endpoint) WritePackets(r *stack.Route, pkts stack.PacketBufferList, params stack.NetworkHeaderParams) (int, tcpip.Error) {
 	if r.Loop()&stack.PacketLoop != 0 {
 		panic("multiple packets in local loop")
@@ -603,34 +603,34 @@ func (e *endpoint) WriteHeaderIncludedPacket(r *stack.Route, pkt *stack.PacketBu
 	if !ok {
 		return &tcpip.ErrMalformedHeader{}
 	}
-	ip := header.IPv4(h)
+	ipH := header.IPv4(h)
 
 	// Always set the total length.
 	pktSize := pkt.Data().Size()
-	ip.SetTotalLength(uint16(pktSize))
+	ipH.SetTotalLength(uint16(pktSize))
 
 	// Set the source address when zero.
-	if ip.SourceAddress() == header.IPv4Any {
-		ip.SetSourceAddress(r.LocalAddress())
+	if ipH.SourceAddress() == header.IPv4Any {
+		ipH.SetSourceAddress(r.LocalAddress())
 	}
 
 	// Set the destination. If the packet already included a destination, it will
 	// be part of the route anyways.
-	ip.SetDestinationAddress(r.RemoteAddress())
+	ipH.SetDestinationAddress(r.RemoteAddress())
 
 	// Set the packet ID when zero.
-	if ip.ID() == 0 {
+	if ipH.ID() == 0 {
 		// RFC 6864 section 4.3 mandates uniqueness of ID values for
 		// non-atomic datagrams, so assign an ID to all such datagrams
 		// according to the definition given in RFC 6864 section 4.
-		if ip.Flags()&header.IPv4FlagDontFragment == 0 || ip.Flags()&header.IPv4FlagMoreFragments != 0 || ip.FragmentOffset() > 0 {
-			ip.SetID(uint16(atomic.AddUint32(&e.protocol.ids[hashRoute(r.LocalAddress(), r.RemoteAddress(), 0 /* protocol */, e.protocol.hashIV)%buckets], 1)))
+		if ipH.Flags()&header.IPv4FlagDontFragment == 0 || ipH.Flags()&header.IPv4FlagMoreFragments != 0 || ipH.FragmentOffset() > 0 {
+			ipH.SetID(uint16(atomic.AddUint32(&e.protocol.ids[hashRoute(r.LocalAddress(), r.RemoteAddress(), 0 /* protocol */, e.protocol.hashIV)%buckets], 1)))
 		}
 	}
 
 	// Always set the checksum.
-	ip.SetChecksum(0)
-	ip.SetChecksum(^ip.CalculateChecksum())
+	ipH.SetChecksum(0)
+	ipH.SetChecksum(^ipH.CalculateChecksum())
 
 	// Populate the packet buffer's network header and don't allow an invalid
 	// packet to be sent.
@@ -993,7 +993,7 @@ func (e *endpoint) handleValidatedPacket(h header.IPv4, pkt *stack.PacketBuffer)
 
 		// The reassembler doesn't take care of fixing up the header, so we need
 		// to do it here.
-		h.SetTotalLength(uint16(pkt.Data().Size() + len((h))))
+		h.SetTotalLength(uint16(pkt.Data().Size() + len(h)))
 		h.SetFlagsFragmentOffset(0, 0)
 	}
 	stats.ip.PacketsDelivered.Increment()
@@ -1224,13 +1224,13 @@ func (p *protocol) DefaultPrefixLen() int {
 	return header.IPv4AddressSize * 8
 }
 
-// ParseAddresses implements NetworkProtocol.ParseAddresses.
+// ParseAddresses implements stack.NetworkProtocol.
 func (*protocol) ParseAddresses(v buffer.View) (src, dst tcpip.Address) {
 	h := header.IPv4(v)
 	return h.SourceAddress(), h.DestinationAddress()
 }
 
-// SetOption implements NetworkProtocol.SetOption.
+// SetOption implements stack.NetworkProtocol.
 func (p *protocol) SetOption(option tcpip.SettableNetworkProtocolOption) tcpip.Error {
 	switch v := option.(type) {
 	case *tcpip.DefaultTTLOption:
@@ -1241,7 +1241,7 @@ func (p *protocol) SetOption(option tcpip.SettableNetworkProtocolOption) tcpip.E
 	}
 }
 
-// Option implements NetworkProtocol.Option.
+// Option implements stack.NetworkProtocol.
 func (p *protocol) Option(option tcpip.GettableNetworkProtocolOption) tcpip.Error {
 	switch v := option.(type) {
 	case *tcpip.DefaultTTLOption:
@@ -1262,10 +1262,10 @@ func (p *protocol) DefaultTTL() uint8 {
 	return uint8(atomic.LoadUint32(&p.defaultTTL))
 }
 
-// Close implements stack.TransportProtocol.Close.
+// Close implements stack.TransportProtocol.
 func (*protocol) Close() {}
 
-// Wait implements stack.TransportProtocol.Wait.
+// Wait implements stack.TransportProtocol.
 func (*protocol) Wait() {}
 
 // parseAndValidate parses the packet (including its transport layer header) and
@@ -1303,7 +1303,7 @@ func (p *protocol) parseAndValidate(pkt *stack.PacketBuffer) (header.IPv4, bool)
 	return h, true
 }
 
-// Parse implements stack.NetworkProtocol.Parse.
+// Parse implements stack.NetworkProtocol.
 func (*protocol) Parse(pkt *stack.PacketBuffer) (proto tcpip.TransportProtocolNumber, hasTransportHdr bool, ok bool) {
 	if ok := parse.IPv4(pkt); !ok {
 		return 0, false, false
@@ -1333,7 +1333,7 @@ func calculateNetworkMTU(linkMTU, networkHeaderSize uint32) (uint32, tcpip.Error
 		networkMTU = MaxTotalSize
 	}
 
-	return networkMTU - uint32(networkHeaderSize), nil
+	return networkMTU - networkHeaderSize, nil
 }
 
 func packetMustBeFragmented(pkt *stack.PacketBuffer, networkMTU uint32) bool {
@@ -1742,9 +1742,8 @@ type optionTracker struct {
 //
 // If there were no errors during parsing, the new set of options is returned as
 // a new buffer.
-func (e *endpoint) processIPOptions(pkt *stack.PacketBuffer, orig header.IPv4Options, usage optionsUsage) (header.IPv4Options, optionTracker, *header.IPv4OptParameterProblem) {
+func (e *endpoint) processIPOptions(pkt *stack.PacketBuffer, opts header.IPv4Options, usage optionsUsage) (header.IPv4Options, optionTracker, *header.IPv4OptParameterProblem) {
 	stats := e.stats.ip
-	opts := header.IPv4Options(orig)
 	optIter := opts.MakeIterator()
 
 	// Except NOP, each option must only appear at most once (RFC 791 section 3.1,
diff --git a/pkg/tcpip/network/ipv4/ipv4_test.go b/pkg/tcpip/network/ipv4/ipv4_test.go
index 0a1f02de0..4a4448cf9 100644
--- a/pkg/tcpip/network/ipv4/ipv4_test.go
+++ b/pkg/tcpip/network/ipv4/ipv4_test.go
@@ -3030,7 +3030,7 @@ func (lm *limitedMatcher) Match(stack.Hook, *stack.PacketBuffer, string, string)
 	return false, false
 }
 
-func TestPacketQueing(t *testing.T) {
+func TestPacketQueuing(t *testing.T) {
 	const nicID = 1
 
 	var (