1 files changed, 106 insertions, 0 deletions
diff --git a/pkg/tcpip/transport/ping/protocol.go b/pkg/tcpip/transport/ping/protocol.go
new file mode 100644
index 000000000..1459b4d60
--- /dev/null
+++ b/pkg/tcpip/transport/ping/protocol.go
@@ -0,0 +1,106 @@
+// Copyright 2016 The Netstack Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package ping contains the implementation of the ICMP and IPv6-ICMP transport
+// protocols for use in ping. To use it in the networking stack, this package
+// must be added to the project, and
+// activated on the stack by passing ping.ProtocolName (or "ping") and/or
+// ping.ProtocolName6 (or "ping6") as one of the transport protocols when
+// calling stack.New(). Then endpoints can be created by passing
+// ping.ProtocolNumber or ping.ProtocolNumber6 as the transport protocol number
+// when calling Stack.NewEndpoint().
+package ping
+
+import (
+	"encoding/binary"
+	"fmt"
+
+	"gvisor.googlesource.com/gvisor/pkg/tcpip"
+	"gvisor.googlesource.com/gvisor/pkg/tcpip/buffer"
+	"gvisor.googlesource.com/gvisor/pkg/tcpip/header"
+	"gvisor.googlesource.com/gvisor/pkg/tcpip/stack"
+	"gvisor.googlesource.com/gvisor/pkg/waiter"
+)
+
+const (
+	// ProtocolName4 is the string representation of the ping protocol name.
+	ProtocolName4 = "ping4"
+
+	// ProtocolNumber4 is the ICMP protocol number.
+	ProtocolNumber4 = header.ICMPv4ProtocolNumber
+
+	// ProtocolName6 is the string representation of the ping protocol name.
+	ProtocolName6 = "ping6"
+
+	// ProtocolNumber6 is the IPv6-ICMP protocol number.
+	ProtocolNumber6 = header.ICMPv6ProtocolNumber
+)
+
+type protocol struct {
+	number tcpip.TransportProtocolNumber
+}
+
+// Number returns the ICMP protocol number.
+func (p *protocol) Number() tcpip.TransportProtocolNumber {
+	return p.number
+}
+
+func (p *protocol) netProto() tcpip.NetworkProtocolNumber {
+	switch p.number {
+	case ProtocolNumber4:
+		return header.IPv4ProtocolNumber
+	case ProtocolNumber6:
+		return header.IPv6ProtocolNumber
+	}
+	panic(fmt.Sprint("unknown protocol number: ", p.number))
+}
+
+// NewEndpoint creates a new ping endpoint.
+func (p *protocol) NewEndpoint(stack *stack.Stack, netProto tcpip.NetworkProtocolNumber, waiterQueue *waiter.Queue) (tcpip.Endpoint, *tcpip.Error) {
+	if netProto != p.netProto() {
+		return nil, tcpip.ErrUnknownProtocol
+	}
+	return newEndpoint(stack, netProto, waiterQueue), nil
+}
+
+// MinimumPacketSize returns the minimum valid ping packet size.
+func (p *protocol) MinimumPacketSize() int {
+	switch p.number {
+	case ProtocolNumber4:
+		return header.ICMPv4EchoMinimumSize
+	case ProtocolNumber6:
+		return header.ICMPv6EchoMinimumSize
+	}
+	panic(fmt.Sprint("unknown protocol number: ", p.number))
+}
+
+// ParsePorts returns the source and destination ports stored in the given udp
+// packet.
+func (*protocol) ParsePorts(v buffer.View) (src, dst uint16, err *tcpip.Error) {
+	return 0, binary.BigEndian.Uint16(v[header.ICMPv4MinimumSize:]), nil
+}
+
+// HandleUnknownDestinationPacket handles packets targeted at this protocol but
+// that don't match any existing endpoint.
+func (p *protocol) HandleUnknownDestinationPacket(*stack.Route, stack.TransportEndpointID, *buffer.VectorisedView) bool {
+	return true
+}
+
+// SetOption implements TransportProtocol.SetOption.
+func (p *protocol) SetOption(option interface{}) *tcpip.Error {
+	return tcpip.ErrUnknownProtocolOption
+}
+
+// Option implements TransportProtocol.Option.
+func (p *protocol) Option(option interface{}) *tcpip.Error {
+	return tcpip.ErrUnknownProtocolOption
+}
+
+func init() {
+	stack.RegisterTransportProtocolFactory(ProtocolName4, func() stack.TransportProtocol {
+		return &protocol{ProtocolNumber4}
+	})
+
+	// TODO: Support IPv6.
+}