diff options
Diffstat (limited to 'pkg/sentry/inet')
| -rw-r--r-- | pkg/sentry/inet/BUILD | 7 | ||||
| -rw-r--r-- | pkg/sentry/inet/context.go | 2 | ||||
| -rw-r--r-- | pkg/sentry/inet/inet.go | 36 | ||||
| -rw-r--r-- | pkg/sentry/inet/namespace.go | 102 | ||||
| -rw-r--r-- | pkg/sentry/inet/test_stack.go | 33 |
5 files changed, 174 insertions, 6 deletions
diff --git a/pkg/sentry/inet/BUILD b/pkg/sentry/inet/BUILD index 99481e05e..5bba9de0b 100644 --- a/pkg/sentry/inet/BUILD +++ b/pkg/sentry/inet/BUILD @@ -1,4 +1,4 @@ -load("//tools/go_stateify:defs.bzl", "go_library") +load("//tools:defs.bzl", "go_library") package( default_visibility = ["//:sandbox"], @@ -10,11 +10,12 @@ go_library( srcs = [ "context.go", "inet.go", + "namespace.go", "test_stack.go", ], - importpath = "gvisor.dev/gvisor/pkg/sentry/inet", deps = [ - "//pkg/sentry/context", + "//pkg/context", "//pkg/tcpip", + "//pkg/tcpip/stack", ], ) diff --git a/pkg/sentry/inet/context.go b/pkg/sentry/inet/context.go index 4eda7dd1f..e8cc1bffd 100644 --- a/pkg/sentry/inet/context.go +++ b/pkg/sentry/inet/context.go @@ -15,7 +15,7 @@ package inet import ( - "gvisor.dev/gvisor/pkg/sentry/context" + "gvisor.dev/gvisor/pkg/context" ) // contextID is the inet package's type for context.Context.Value keys. diff --git a/pkg/sentry/inet/inet.go b/pkg/sentry/inet/inet.go index 6217100b2..fbe6d6aa6 100644 --- a/pkg/sentry/inet/inet.go +++ b/pkg/sentry/inet/inet.go @@ -15,7 +15,10 @@ // Package inet defines semantics for IP stacks. package inet -import "gvisor.dev/gvisor/pkg/tcpip" +import ( + "gvisor.dev/gvisor/pkg/tcpip" + "gvisor.dev/gvisor/pkg/tcpip/stack" +) // Stack represents a TCP/IP stack. type Stack interface { @@ -28,6 +31,10 @@ type Stack interface { // interface indexes to a slice of associated interface address properties. InterfaceAddrs() map[int32][]InterfaceAddr + // AddInterfaceAddr adds an address to the network interface identified by + // index. + AddInterfaceAddr(idx int32, addr InterfaceAddr) error + // SupportsIPv6 returns true if the stack supports IPv6 connectivity. SupportsIPv6() bool @@ -52,6 +59,12 @@ type Stack interface { // settings. SetTCPSACKEnabled(enabled bool) error + // TCPRecovery returns the TCP loss detection algorithm. + TCPRecovery() (TCPLossRecovery, error) + + // SetTCPRecovery attempts to change TCP loss detection algorithm. + SetTCPRecovery(recovery TCPLossRecovery) error + // Statistics reports stack statistics. Statistics(stat interface{}, arg string) error @@ -61,6 +74,16 @@ type Stack interface { // Resume restarts the network stack after restore. Resume() + // RegisteredEndpoints returns all endpoints which are currently registered. + RegisteredEndpoints() []stack.TransportEndpoint + + // CleanupEndpoints returns endpoints currently in the cleanup state. + CleanupEndpoints() []stack.TransportEndpoint + + // RestoreCleanupEndpoints adds endpoints to cleanup tracking. This is useful + // for restoring a stack after a save. + RestoreCleanupEndpoints([]stack.TransportEndpoint) + // Forwarding returns if packet forwarding between NICs is enabled. Forwarding(protocol tcpip.NetworkProtocolNumber) bool @@ -181,3 +204,14 @@ type StatSNMPUDP [8]uint64 // StatSNMPUDPLite describes UdpLite line of /proc/net/snmp. type StatSNMPUDPLite [8]uint64 + +// TCPLossRecovery indicates TCP loss detection and recovery methods to use. +type TCPLossRecovery int32 + +// Loss recovery constants from include/net/tcp.h which are used to set +// /proc/sys/net/ipv4/tcp_recovery. +const ( + TCP_RACK_LOSS_DETECTION TCPLossRecovery = 1 << iota + TCP_RACK_STATIC_REO_WND + TCP_RACK_NO_DUPTHRESH +) diff --git a/pkg/sentry/inet/namespace.go b/pkg/sentry/inet/namespace.go new file mode 100644 index 000000000..029af3025 --- /dev/null +++ b/pkg/sentry/inet/namespace.go @@ -0,0 +1,102 @@ +// Copyright 2020 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 inet + +// Namespace represents a network namespace. See network_namespaces(7). +// +// +stateify savable +type Namespace struct { + // stack is the network stack implementation of this network namespace. + stack Stack `state:"nosave"` + + // creator allows kernel to create new network stack for network namespaces. + // If nil, no networking will function if network is namespaced. + // + // At afterLoad(), creator will be used to create network stack. Stateify + // needs to wait for this field to be loaded before calling afterLoad(). + creator NetworkStackCreator `state:"wait"` + + // isRoot indicates whether this is the root network namespace. + isRoot bool +} + +// NewRootNamespace creates the root network namespace, with creator +// allowing new network namespaces to be created. If creator is nil, no +// networking will function if the network is namespaced. +func NewRootNamespace(stack Stack, creator NetworkStackCreator) *Namespace { + return &Namespace{ + stack: stack, + creator: creator, + isRoot: true, + } +} + +// NewNamespace creates a new network namespace from the root. +func NewNamespace(root *Namespace) *Namespace { + n := &Namespace{ + creator: root.creator, + } + n.init() + return n +} + +// Stack returns the network stack of n. Stack may return nil if no network +// stack is configured. +func (n *Namespace) Stack() Stack { + return n.stack +} + +// IsRoot returns whether n is the root network namespace. +func (n *Namespace) IsRoot() bool { + return n.isRoot +} + +// RestoreRootStack restores the root network namespace with stack. This should +// only be called when restoring kernel. +func (n *Namespace) RestoreRootStack(stack Stack) { + if !n.isRoot { + panic("RestoreRootStack can only be called on root network namespace") + } + if n.stack != nil { + panic("RestoreRootStack called after a stack has already been set") + } + n.stack = stack +} + +func (n *Namespace) init() { + // Root network namespace will have stack assigned later. + if n.isRoot { + return + } + if n.creator != nil { + var err error + n.stack, err = n.creator.CreateStack() + if err != nil { + panic(err) + } + } +} + +// afterLoad is invoked by stateify. +func (n *Namespace) afterLoad() { + n.init() +} + +// NetworkStackCreator allows new instances of a network stack to be created. It +// is used by the kernel to create new network namespaces when requested. +type NetworkStackCreator interface { + // CreateStack creates a new network stack for a network namespace. + CreateStack() (Stack, error) +} diff --git a/pkg/sentry/inet/test_stack.go b/pkg/sentry/inet/test_stack.go index c6907cfcb..1779cc6f3 100644 --- a/pkg/sentry/inet/test_stack.go +++ b/pkg/sentry/inet/test_stack.go @@ -16,6 +16,7 @@ package inet import ( "gvisor.dev/gvisor/pkg/tcpip" + "gvisor.dev/gvisor/pkg/tcpip/stack" ) // TestStack is a dummy implementation of Stack for tests. @@ -27,6 +28,7 @@ type TestStack struct { TCPRecvBufSize TCPBufferSize TCPSendBufSize TCPBufferSize TCPSACKFlag bool + Recovery TCPLossRecovery IPForwarding bool } @@ -50,6 +52,12 @@ func (s *TestStack) InterfaceAddrs() map[int32][]InterfaceAddr { return s.InterfaceAddrsMap } +// AddInterfaceAddr implements Stack.AddInterfaceAddr. +func (s *TestStack) AddInterfaceAddr(idx int32, addr InterfaceAddr) error { + s.InterfaceAddrsMap[idx] = append(s.InterfaceAddrsMap[idx], addr) + return nil +} + // SupportsIPv6 implements Stack.SupportsIPv6. func (s *TestStack) SupportsIPv6() bool { return s.SupportsIPv6Flag @@ -88,6 +96,17 @@ func (s *TestStack) SetTCPSACKEnabled(enabled bool) error { return nil } +// TCPRecovery implements Stack.TCPRecovery. +func (s *TestStack) TCPRecovery() (TCPLossRecovery, error) { + return s.Recovery, nil +} + +// SetTCPRecovery implements Stack.SetTCPRecovery. +func (s *TestStack) SetTCPRecovery(recovery TCPLossRecovery) error { + s.Recovery = recovery + return nil +} + // Statistics implements inet.Stack.Statistics. func (s *TestStack) Statistics(stat interface{}, arg string) error { return nil @@ -99,9 +118,21 @@ func (s *TestStack) RouteTable() []Route { } // Resume implements Stack.Resume. -func (s *TestStack) Resume() { +func (s *TestStack) Resume() {} + +// RegisteredEndpoints implements inet.Stack.RegisteredEndpoints. +func (s *TestStack) RegisteredEndpoints() []stack.TransportEndpoint { + return nil } +// CleanupEndpoints implements inet.Stack.CleanupEndpoints. +func (s *TestStack) CleanupEndpoints() []stack.TransportEndpoint { + return nil +} + +// RestoreCleanupEndpoints implements inet.Stack.RestoreCleanupEndpoints. +func (s *TestStack) RestoreCleanupEndpoints([]stack.TransportEndpoint) {} + // Forwarding implements inet.Stack.Forwarding. func (s *TestStack) Forwarding(protocol tcpip.NetworkProtocolNumber) bool { return s.IPForwarding |