Add IPPROTO_RAW, which allows raw sockets to write IP headers.

iptables also relies on IPPROTO_RAW in a way. It opens such a socket to
manipulate the kernel's tables, but it doesn't actually use any of the
functionality. Blegh.

PiperOrigin-RevId: 257903078

1 files changed, 20 insertions, 0 deletions

diff --git a/pkg/tcpip/stack/registration.go b/pkg/tcpip/stack/registration.go
index 0ecaa0833..462265281 100644
--- a/pkg/tcpip/stack/registration.go
+++ b/pkg/tcpip/stack/registration.go
@@ -174,6 +174,10 @@ type NetworkEndpoint interface {
 	// protocol.
 	WritePacket(r *Route, gso *GSO, hdr buffer.Prependable, payload buffer.VectorisedView, protocol tcpip.TransportProtocolNumber, ttl uint8, loop PacketLooping) *tcpip.Error
 
+	// WriteHeaderIncludedPacket writes a packet that includes a network
+	// header to the given destination address.
+	WriteHeaderIncludedPacket(r *Route, payload buffer.VectorisedView, loop PacketLooping) *tcpip.Error
+
 	// ID returns the network protocol endpoint ID.
 	ID() *NetworkEndpointID
 
@@ -357,10 +361,19 @@ type TransportProtocolFactory func() TransportProtocol
 // instantiate network protocols.
 type NetworkProtocolFactory func() NetworkProtocol
 
+// UnassociatedEndpointFactory produces endpoints for writing packets not
+// associated with a particular transport protocol. Such endpoints can be used
+// to write arbitrary packets that include the IP header.
+type UnassociatedEndpointFactory interface {
+	NewUnassociatedRawEndpoint(stack *Stack, netProto tcpip.NetworkProtocolNumber, transProto tcpip.TransportProtocolNumber, waiterQueue *waiter.Queue) (tcpip.Endpoint, *tcpip.Error)
+}
+
 var (
 	transportProtocols = make(map[string]TransportProtocolFactory)
 	networkProtocols   = make(map[string]NetworkProtocolFactory)
 
+	unassociatedFactory UnassociatedEndpointFactory
+
 	linkEPMu           sync.RWMutex
 	nextLinkEndpointID tcpip.LinkEndpointID = 1
 	linkEndpoints                           = make(map[tcpip.LinkEndpointID]LinkEndpoint)
@@ -380,6 +393,13 @@ func RegisterNetworkProtocolFactory(name string, p NetworkProtocolFactory) {
 	networkProtocols[name] = p
 }
 
+// RegisterUnassociatedFactory registers a factory to produce endpoints not
+// associated with any particular transport protocol. This function is intended
+// to be called by init() functions of the protocols.
+func RegisterUnassociatedFactory(f UnassociatedEndpointFactory) {
+	unassociatedFactory = f
+}
+
 // RegisterLinkEndpoint register a link-layer protocol endpoint and returns an
 // ID that can be used to refer to it.
 func RegisterLinkEndpoint(linkEP LinkEndpoint) tcpip.LinkEndpointID {