Rename epsocket to netstack.

PiperOrigin-RevId: 273365058

1 files changed, 202 insertions, 0 deletions

diff --git a/pkg/sentry/socket/netstack/stack.go b/pkg/sentry/socket/netstack/stack.go
new file mode 100644
index 000000000..fda0156e5
--- /dev/null
+++ b/pkg/sentry/socket/netstack/stack.go
@@ -0,0 +1,202 @@
+// Copyright 2018 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package netstack
+
+import (
+	"gvisor.dev/gvisor/pkg/abi/linux"
+	"gvisor.dev/gvisor/pkg/log"
+	"gvisor.dev/gvisor/pkg/sentry/inet"
+	"gvisor.dev/gvisor/pkg/sentry/socket/netfilter"
+	"gvisor.dev/gvisor/pkg/syserr"
+	"gvisor.dev/gvisor/pkg/tcpip/header"
+	"gvisor.dev/gvisor/pkg/tcpip/iptables"
+	"gvisor.dev/gvisor/pkg/tcpip/network/ipv4"
+	"gvisor.dev/gvisor/pkg/tcpip/network/ipv6"
+	"gvisor.dev/gvisor/pkg/tcpip/stack"
+	"gvisor.dev/gvisor/pkg/tcpip/transport/tcp"
+)
+
+// Stack implements inet.Stack for netstack/tcpip/stack.Stack.
+//
+// +stateify savable
+type Stack struct {
+	Stack *stack.Stack `state:"manual"`
+}
+
+// SupportsIPv6 implements Stack.SupportsIPv6.
+func (s *Stack) SupportsIPv6() bool {
+	return s.Stack.CheckNetworkProtocol(ipv6.ProtocolNumber)
+}
+
+// Interfaces implements inet.Stack.Interfaces.
+func (s *Stack) Interfaces() map[int32]inet.Interface {
+	is := make(map[int32]inet.Interface)
+	for id, ni := range s.Stack.NICInfo() {
+		var devType uint16
+		if ni.Flags.Loopback {
+			devType = linux.ARPHRD_LOOPBACK
+		}
+		is[int32(id)] = inet.Interface{
+			Name:       ni.Name,
+			Addr:       []byte(ni.LinkAddress),
+			Flags:      uint32(nicStateFlagsToLinux(ni.Flags)),
+			DeviceType: devType,
+			MTU:        ni.MTU,
+		}
+	}
+	return is
+}
+
+// InterfaceAddrs implements inet.Stack.InterfaceAddrs.
+func (s *Stack) InterfaceAddrs() map[int32][]inet.InterfaceAddr {
+	nicAddrs := make(map[int32][]inet.InterfaceAddr)
+	for id, ni := range s.Stack.NICInfo() {
+		var addrs []inet.InterfaceAddr
+		for _, a := range ni.ProtocolAddresses {
+			var family uint8
+			switch a.Protocol {
+			case ipv4.ProtocolNumber:
+				family = linux.AF_INET
+			case ipv6.ProtocolNumber:
+				family = linux.AF_INET6
+			default:
+				log.Warningf("Unknown network protocol in %+v", a)
+				continue
+			}
+
+			addrs = append(addrs, inet.InterfaceAddr{
+				Family:    family,
+				PrefixLen: uint8(a.AddressWithPrefix.PrefixLen),
+				Addr:      []byte(a.AddressWithPrefix.Address),
+				// TODO(b/68878065): Other fields.
+			})
+		}
+		nicAddrs[int32(id)] = addrs
+	}
+	return nicAddrs
+}
+
+// TCPReceiveBufferSize implements inet.Stack.TCPReceiveBufferSize.
+func (s *Stack) TCPReceiveBufferSize() (inet.TCPBufferSize, error) {
+	var rs tcp.ReceiveBufferSizeOption
+	err := s.Stack.TransportProtocolOption(tcp.ProtocolNumber, &rs)
+	return inet.TCPBufferSize{
+		Min:     rs.Min,
+		Default: rs.Default,
+		Max:     rs.Max,
+	}, syserr.TranslateNetstackError(err).ToError()
+}
+
+// SetTCPReceiveBufferSize implements inet.Stack.SetTCPReceiveBufferSize.
+func (s *Stack) SetTCPReceiveBufferSize(size inet.TCPBufferSize) error {
+	rs := tcp.ReceiveBufferSizeOption{
+		Min:     size.Min,
+		Default: size.Default,
+		Max:     size.Max,
+	}
+	return syserr.TranslateNetstackError(s.Stack.SetTransportProtocolOption(tcp.ProtocolNumber, rs)).ToError()
+}
+
+// TCPSendBufferSize implements inet.Stack.TCPSendBufferSize.
+func (s *Stack) TCPSendBufferSize() (inet.TCPBufferSize, error) {
+	var ss tcp.SendBufferSizeOption
+	err := s.Stack.TransportProtocolOption(tcp.ProtocolNumber, &ss)
+	return inet.TCPBufferSize{
+		Min:     ss.Min,
+		Default: ss.Default,
+		Max:     ss.Max,
+	}, syserr.TranslateNetstackError(err).ToError()
+}
+
+// SetTCPSendBufferSize implements inet.Stack.SetTCPSendBufferSize.
+func (s *Stack) SetTCPSendBufferSize(size inet.TCPBufferSize) error {
+	ss := tcp.SendBufferSizeOption{
+		Min:     size.Min,
+		Default: size.Default,
+		Max:     size.Max,
+	}
+	return syserr.TranslateNetstackError(s.Stack.SetTransportProtocolOption(tcp.ProtocolNumber, ss)).ToError()
+}
+
+// TCPSACKEnabled implements inet.Stack.TCPSACKEnabled.
+func (s *Stack) TCPSACKEnabled() (bool, error) {
+	var sack tcp.SACKEnabled
+	err := s.Stack.TransportProtocolOption(tcp.ProtocolNumber, &sack)
+	return bool(sack), syserr.TranslateNetstackError(err).ToError()
+}
+
+// SetTCPSACKEnabled implements inet.Stack.SetTCPSACKEnabled.
+func (s *Stack) SetTCPSACKEnabled(enabled bool) error {
+	return syserr.TranslateNetstackError(s.Stack.SetTransportProtocolOption(tcp.ProtocolNumber, tcp.SACKEnabled(enabled))).ToError()
+}
+
+// Statistics implements inet.Stack.Statistics.
+func (s *Stack) Statistics(stat interface{}, arg string) error {
+	return syserr.ErrEndpointOperation.ToError()
+}
+
+// RouteTable implements inet.Stack.RouteTable.
+func (s *Stack) RouteTable() []inet.Route {
+	var routeTable []inet.Route
+
+	for _, rt := range s.Stack.GetRouteTable() {
+		var family uint8
+		switch len(rt.Destination.ID()) {
+		case header.IPv4AddressSize:
+			family = linux.AF_INET
+		case header.IPv6AddressSize:
+			family = linux.AF_INET6
+		default:
+			log.Warningf("Unknown network protocol in route %+v", rt)
+			continue
+		}
+
+		routeTable = append(routeTable, inet.Route{
+			Family: family,
+			DstLen: uint8(rt.Destination.Prefix()), // The CIDR prefix for the destination.
+
+			// Always return unspecified protocol since we have no notion of
+			// protocol for routes.
+			Protocol: linux.RTPROT_UNSPEC,
+			// Set statically to LINK scope for now.
+			//
+			// TODO(gvisor.dev/issue/595): Set scope for routes.
+			Scope: linux.RT_SCOPE_LINK,
+			Type:  linux.RTN_UNICAST,
+
+			DstAddr:         []byte(rt.Destination.ID()),
+			OutputInterface: int32(rt.NIC),
+			GatewayAddr:     []byte(rt.Gateway),
+		})
+	}
+
+	return routeTable
+}
+
+// IPTables returns the stack's iptables.
+func (s *Stack) IPTables() (iptables.IPTables, error) {
+	return s.Stack.IPTables(), nil
+}
+
+// FillDefaultIPTables sets the stack's iptables to the default tables, which
+// allow and do not modify all traffic.
+func (s *Stack) FillDefaultIPTables() {
+	netfilter.FillDefaultIPTables(s.Stack)
+}
+
+// Resume implements inet.Stack.Resume.
+func (s *Stack) Resume() {
+	s.Stack.Resume()
+}