Make dedicated methods for data operations in PacketBuffer

One of the preparation to decouple underlying buffer implementation.
There are still some methods that tie to VectorisedView, and they will be
changed gradually in later CLs.

This CL also introduce a new ICMPv6ChecksumParams to replace long list of
parameters when calling ICMPv6Checksum, aiming to be more descriptive.

PiperOrigin-RevId: 360778149

1 files changed, 11 insertions, 5 deletions

diff --git a/pkg/tcpip/transport/icmp/endpoint.go b/pkg/tcpip/transport/icmp/endpoint.go
index f5e1a6e45..09e9d027d 100644
--- a/pkg/tcpip/transport/icmp/endpoint.go
+++ b/pkg/tcpip/transport/icmp/endpoint.go
@@ -417,7 +417,7 @@ func send4(r *stack.Route, ident uint16, data buffer.View, ttl uint8, owner tcpi
 	icmpv4.SetChecksum(0)
 	icmpv4.SetChecksum(^header.Checksum(icmpv4, header.Checksum(data, 0)))
 
-	pkt.Data = data.ToVectorisedView()
+	pkt.Data().AppendView(data)
 
 	if ttl == 0 {
 		ttl = r.DefaultTTL()
@@ -445,9 +445,15 @@ func send6(r *stack.Route, ident uint16, data buffer.View, ttl uint8) tcpip.Erro
 		return &tcpip.ErrInvalidEndpointState{}
 	}
 
-	dataVV := data.ToVectorisedView()
-	icmpv6.SetChecksum(header.ICMPv6Checksum(icmpv6, r.LocalAddress, r.RemoteAddress, dataVV))
-	pkt.Data = dataVV
+	pkt.Data().AppendView(data)
+	dataRange := pkt.Data().AsRange()
+	icmpv6.SetChecksum(header.ICMPv6Checksum(header.ICMPv6ChecksumParams{
+		Header:      icmpv6,
+		Src:         r.LocalAddress,
+		Dst:         r.RemoteAddress,
+		PayloadCsum: dataRange.Checksum(),
+		PayloadLen:  dataRange.Size(),
+	}))
 
 	if ttl == 0 {
 		ttl = r.DefaultTTL()
@@ -763,7 +769,7 @@ func (e *endpoint) HandlePacket(id stack.TransportEndpointID, pkt *stack.PacketB
 
 	// ICMP socket's data includes ICMP header.
 	packet.data = pkt.TransportHeader().View().ToVectorisedView()
-	packet.data.Append(pkt.Data)
+	packet.data.Append(pkt.Data().ExtractVV())
 
 	e.rcvList.PushBack(packet)
 	e.rcvBufSize += packet.data.Size()