From db37483cb6acf55b66132d534bb734f09555b1cf Mon Sep 17 00:00:00 2001 From: Andrei Vagin 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 ++++++++--- pkg/tcpip/transport/icmp/endpoint.go | 7 +++++++ pkg/tcpip/transport/tcp/endpoint.go | 7 +++++++ pkg/tcpip/transport/udp/endpoint.go | 7 +++++++ 7 files changed, 71 insertions(+), 3 deletions(-) (limited to 'pkg/tcpip') 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) { diff --git a/pkg/tcpip/transport/icmp/endpoint.go b/pkg/tcpip/transport/icmp/endpoint.go index d0dd383fd..114a69b4e 100644 --- a/pkg/tcpip/transport/icmp/endpoint.go +++ b/pkg/tcpip/transport/icmp/endpoint.go @@ -58,6 +58,7 @@ type endpoint struct { // immutable. stack *stack.Stack `state:"manual"` waiterQueue *waiter.Queue + uniqueID uint64 // The following fields are used to manage the receive queue, and are // protected by rcvMu. @@ -90,9 +91,15 @@ func newEndpoint(s *stack.Stack, netProto tcpip.NetworkProtocolNumber, transProt rcvBufSizeMax: 32 * 1024, sndBufSize: 32 * 1024, state: stateInitial, + uniqueID: s.UniqueID(), }, nil } +// UniqueID implements stack.TransportEndpoint.UniqueID. +func (e *endpoint) UniqueID() uint64 { + return e.uniqueID +} + // Close puts the endpoint in a closed state and frees all resources // associated with it. func (e *endpoint) Close() { diff --git a/pkg/tcpip/transport/tcp/endpoint.go b/pkg/tcpip/transport/tcp/endpoint.go index 8a3ca0f1b..a1efd8d55 100644 --- a/pkg/tcpip/transport/tcp/endpoint.go +++ b/pkg/tcpip/transport/tcp/endpoint.go @@ -287,6 +287,7 @@ type endpoint struct { // change throughout the lifetime of the endpoint. stack *stack.Stack `state:"manual"` waiterQueue *waiter.Queue `state:"wait"` + uniqueID uint64 // lastError represents the last error that the endpoint reported; // access to it is protected by the following mutex. @@ -504,6 +505,11 @@ type endpoint struct { stats Stats `state:"nosave"` } +// UniqueID implements stack.TransportEndpoint.UniqueID. +func (e *endpoint) UniqueID() uint64 { + return e.uniqueID +} + // calculateAdvertisedMSS calculates the MSS to advertise. // // If userMSS is non-zero and is not greater than the maximum possible MSS for @@ -565,6 +571,7 @@ func newEndpoint(s *stack.Stack, netProto tcpip.NetworkProtocolNumber, waiterQue interval: 75 * time.Second, count: 9, }, + uniqueID: s.UniqueID(), } var ss SendBufferSizeOption diff --git a/pkg/tcpip/transport/udp/endpoint.go b/pkg/tcpip/transport/udp/endpoint.go index cda302bb7..68977dc25 100644 --- a/pkg/tcpip/transport/udp/endpoint.go +++ b/pkg/tcpip/transport/udp/endpoint.go @@ -80,6 +80,7 @@ type endpoint struct { // change throughout the lifetime of the endpoint. stack *stack.Stack `state:"manual"` waiterQueue *waiter.Queue + uniqueID uint64 // The following fields are used to manage the receive queue, and are // protected by rcvMu. @@ -160,9 +161,15 @@ func newEndpoint(s *stack.Stack, netProto tcpip.NetworkProtocolNumber, waiterQue rcvBufSizeMax: 32 * 1024, sndBufSize: 32 * 1024, state: StateInitial, + uniqueID: s.UniqueID(), } } +// UniqueID implements stack.TransportEndpoint.UniqueID. +func (e *endpoint) UniqueID() uint64 { + return e.uniqueID +} + // Close puts the endpoint in a closed state and frees all resources // associated with it. func (e *endpoint) Close() { -- cgit v1.2.3