From db37483cb6acf55b66132d534bb734f09555b1cf Mon Sep 17 00:00:00 2001
From: Andrei Vagin <avagin@google.com>
Date: Wed, 30 Oct 2019 15:32:20 -0700
Subject: Store endpoints inside multiPortEndpoint in a sorted order
It is required to guarantee the same order of endpoints after save/restore.
PiperOrigin-RevId: 277598665
---
pkg/tcpip/stack/registration.go | 3 +++
pkg/tcpip/stack/stack.go | 29 +++++++++++++++++++++++++++++
pkg/tcpip/stack/transport_demuxer.go | 10 ++++++++++
pkg/tcpip/stack/transport_test.go | 11 ++++++++---
4 files changed, 50 insertions(+), 3 deletions(-)
(limited to 'pkg/tcpip/stack')
diff --git a/pkg/tcpip/stack/registration.go b/pkg/tcpip/stack/registration.go
index 0360187b8..94015ba54 100644
--- a/pkg/tcpip/stack/registration.go
+++ b/pkg/tcpip/stack/registration.go
@@ -60,6 +60,9 @@ const (
// TransportEndpoint is the interface that needs to be implemented by transport
// protocol (e.g., tcp, udp) endpoints that can handle packets.
type TransportEndpoint interface {
+ // UniqueID returns an unique ID for this transport endpoint.
+ UniqueID() uint64
+
// HandlePacket is called by the stack when new packets arrive to
// this transport endpoint.
HandlePacket(r *Route, id TransportEndpointID, vv buffer.VectorisedView)
diff --git a/pkg/tcpip/stack/stack.go b/pkg/tcpip/stack/stack.go
index 6d6ddc0ff..115a6fcb8 100644
--- a/pkg/tcpip/stack/stack.go
+++ b/pkg/tcpip/stack/stack.go
@@ -22,6 +22,7 @@ package stack
import (
"encoding/binary"
"sync"
+ "sync/atomic"
"time"
"golang.org/x/time/rate"
@@ -344,6 +345,13 @@ type ResumableEndpoint interface {
Resume(*Stack)
}
+// uniqueIDGenerator is a default unique ID generator.
+type uniqueIDGenerator uint64
+
+func (u *uniqueIDGenerator) UniqueID() uint64 {
+ return atomic.AddUint64((*uint64)(u), 1)
+}
+
// Stack is a networking stack, with all supported protocols, NICs, and route
// table.
type Stack struct {
@@ -411,6 +419,14 @@ type Stack struct {
// ndpDisp is the NDP event dispatcher that is used to send the netstack
// integrator NDP related events.
ndpDisp NDPDispatcher
+
+ // uniqueIDGenerator is a generator of unique identifiers.
+ uniqueIDGenerator UniqueID
+}
+
+// UniqueID is an abstract generator of unique identifiers.
+type UniqueID interface {
+ UniqueID() uint64
}
// Options contains optional Stack configuration.
@@ -434,6 +450,9 @@ type Options struct {
// stack (false).
HandleLocal bool
+ // UniqueID is an optional generator of unique identifiers.
+ UniqueID UniqueID
+
// NDPConfigs is the default NDP configurations used by interfaces.
//
// By default, NDPConfigs will have a zero value for its
@@ -506,6 +525,10 @@ func New(opts Options) *Stack {
clock = &tcpip.StdClock{}
}
+ if opts.UniqueID == nil {
+ opts.UniqueID = new(uniqueIDGenerator)
+ }
+
// Make sure opts.NDPConfigs contains valid values only.
opts.NDPConfigs.validate()
@@ -524,6 +547,7 @@ func New(opts Options) *Stack {
portSeed: generateRandUint32(),
ndpConfigs: opts.NDPConfigs,
autoGenIPv6LinkLocal: opts.AutoGenIPv6LinkLocal,
+ uniqueIDGenerator: opts.UniqueID,
ndpDisp: opts.NDPDisp,
}
@@ -551,6 +575,11 @@ func New(opts Options) *Stack {
return s
}
+// UniqueID returns a unique identifier.
+func (s *Stack) UniqueID() uint64 {
+ return s.uniqueIDGenerator.UniqueID()
+}
+
// SetNetworkProtocolOption allows configuring individual protocol level
// options. This method returns an error if the protocol is not supported or
// option is not supported by the protocol implementation or the provided value
diff --git a/pkg/tcpip/stack/transport_demuxer.go b/pkg/tcpip/stack/transport_demuxer.go
index f633632f0..ccd3d030e 100644
--- a/pkg/tcpip/stack/transport_demuxer.go
+++ b/pkg/tcpip/stack/transport_demuxer.go
@@ -17,6 +17,7 @@ package stack
import (
"fmt"
"math/rand"
+ "sort"
"sync"
"gvisor.dev/gvisor/pkg/tcpip"
@@ -310,6 +311,15 @@ func (ep *multiPortEndpoint) singleRegisterEndpoint(t TransportEndpoint, reusePo
// endpointsMap. This will allow us to remove endpoint from the array fast.
ep.endpointsMap[t] = len(ep.endpointsArr)
ep.endpointsArr = append(ep.endpointsArr, t)
+
+ // ep.endpointsArr is sorted by endpoint unique IDs, so that endpoints
+ // can be restored in the same order.
+ sort.Slice(ep.endpointsArr, func(i, j int) bool {
+ return ep.endpointsArr[i].UniqueID() < ep.endpointsArr[j].UniqueID()
+ })
+ for i, e := range ep.endpointsArr {
+ ep.endpointsMap[e] = i
+ }
return nil
}
diff --git a/pkg/tcpip/stack/transport_test.go b/pkg/tcpip/stack/transport_test.go
index ae6fda3a9..203e79f56 100644
--- a/pkg/tcpip/stack/transport_test.go
+++ b/pkg/tcpip/stack/transport_test.go
@@ -43,6 +43,7 @@ type fakeTransportEndpoint struct {
proto *fakeTransportProtocol
peerAddr tcpip.Address
route stack.Route
+ uniqueID uint64
// acceptQueue is non-nil iff bound.
acceptQueue []fakeTransportEndpoint
@@ -56,8 +57,8 @@ func (f *fakeTransportEndpoint) Stats() tcpip.EndpointStats {
return nil
}
-func newFakeTransportEndpoint(s *stack.Stack, proto *fakeTransportProtocol, netProto tcpip.NetworkProtocolNumber) tcpip.Endpoint {
- return &fakeTransportEndpoint{stack: s, TransportEndpointInfo: stack.TransportEndpointInfo{NetProto: netProto}, proto: proto}
+func newFakeTransportEndpoint(s *stack.Stack, proto *fakeTransportProtocol, netProto tcpip.NetworkProtocolNumber, uniqueID uint64) tcpip.Endpoint {
+ return &fakeTransportEndpoint{stack: s, TransportEndpointInfo: stack.TransportEndpointInfo{NetProto: netProto}, proto: proto, uniqueID: uniqueID}
}
func (f *fakeTransportEndpoint) Close() {
@@ -144,6 +145,10 @@ func (f *fakeTransportEndpoint) Connect(addr tcpip.FullAddress) *tcpip.Error {
return nil
}
+func (f *fakeTransportEndpoint) UniqueID() uint64 {
+ return f.uniqueID
+}
+
func (f *fakeTransportEndpoint) ConnectEndpoint(e tcpip.Endpoint) *tcpip.Error {
return nil
}
@@ -251,7 +256,7 @@ func (*fakeTransportProtocol) Number() tcpip.TransportProtocolNumber {
}
func (f *fakeTransportProtocol) NewEndpoint(stack *stack.Stack, netProto tcpip.NetworkProtocolNumber, _ *waiter.Queue) (tcpip.Endpoint, *tcpip.Error) {
- return newFakeTransportEndpoint(stack, f, netProto), nil
+ return newFakeTransportEndpoint(stack, f, netProto, stack.UniqueID()), nil
}
func (f *fakeTransportProtocol) NewRawEndpoint(stack *stack.Stack, netProto tcpip.NetworkProtocolNumber, _ *waiter.Queue) (tcpip.Endpoint, *tcpip.Error) {
--
cgit v1.2.3