diff options
| -rw-r--r-- | pkg/tcpip/network/arp/arp.go | 76 | ||||
| -rw-r--r-- | pkg/tcpip/network/ipv4/ipv4.go | 244 | ||||
| -rw-r--r-- | pkg/tcpip/network/ipv6/dhcpv6configurationfromndpra_string.go (renamed from pkg/tcpip/stack/dhcpv6configurationfromndpra_string.go) | 2 | ||||
| -rw-r--r-- | pkg/tcpip/network/ipv6/icmp.go | 64 | ||||
| -rw-r--r-- | pkg/tcpip/network/ipv6/ipv6.go | 746 | ||||
| -rw-r--r-- | pkg/tcpip/network/ipv6/ndp.go (renamed from pkg/tcpip/stack/ndp.go) | 576 | ||||
| -rw-r--r-- | pkg/tcpip/stack/addressable_endpoint_state.go | 717 | ||||
| -rw-r--r-- | pkg/tcpip/stack/neighbor_entry.go | 17 | ||||
| -rw-r--r-- | pkg/tcpip/stack/nic.go | 1293 | ||||
| -rw-r--r-- | pkg/tcpip/stack/registration.go | 261 | ||||
| -rw-r--r-- | pkg/tcpip/stack/route.go | 118 | ||||
| -rw-r--r-- | pkg/tcpip/stack/stack.go | 337 | ||||
| -rw-r--r-- | pkg/tcpip/stack/transport_demuxer.go | 4 | ||||
| -rw-r--r-- | pkg/tcpip/tcpip.go | 8 |
14 files changed, 2690 insertions, 1773 deletions
diff --git a/pkg/tcpip/network/arp/arp.go b/pkg/tcpip/network/arp/arp.go index b025bb087..4bb7a417c 100644 --- a/pkg/tcpip/network/arp/arp.go +++ b/pkg/tcpip/network/arp/arp.go @@ -18,6 +18,8 @@ package arp import ( + "sync/atomic" + "gvisor.dev/gvisor/pkg/tcpip" "gvisor.dev/gvisor/pkg/tcpip/buffer" "gvisor.dev/gvisor/pkg/tcpip/header" @@ -33,15 +35,57 @@ const ( ProtocolAddress = tcpip.Address("arp") ) -// endpoint implements stack.NetworkEndpoint. +var _ stack.AddressableEndpoint = (*endpoint)(nil) +var _ stack.NetworkEndpoint = (*endpoint)(nil) + type endpoint struct { - protocol *protocol - nicID tcpip.NICID + stack.AddressableEndpointState + + protocol *protocol + + // enabled is set to 1 when the NIC is enabled and 0 when it is disabled. + // + // Must be accessed using atomic operations. + enabled uint32 + + nic stack.NetworkInterface linkEP stack.LinkEndpoint linkAddrCache stack.LinkAddressCache nud stack.NUDHandler } +func (e *endpoint) Enable() *tcpip.Error { + if !e.nic.Enabled() { + return tcpip.ErrNotPermitted + } + + e.setEnabled(true) + return nil +} + +func (e *endpoint) Enabled() bool { + return e.nic.Enabled() && e.isEnabled() +} + +// isEnabled returns true if the endpoint is enabled, regardless of the +// enabled status of the NIC. +func (e *endpoint) isEnabled() bool { + return atomic.LoadUint32(&e.enabled) == 1 +} + +// setEnabled sets the enabled status for the endpoint. +func (e *endpoint) setEnabled(v bool) { + if v { + atomic.StoreUint32(&e.enabled, 1) + } else { + atomic.StoreUint32(&e.enabled, 0) + } +} + +func (e *endpoint) Disable() { + e.setEnabled(false) +} + // DefaultTTL is unused for ARP. It implements stack.NetworkEndpoint. func (e *endpoint) DefaultTTL() uint8 { return 0 @@ -53,7 +97,7 @@ func (e *endpoint) MTU() uint32 { } func (e *endpoint) NICID() tcpip.NICID { - return e.nicID + return e.nic.ID() } func (e *endpoint) Capabilities() stack.LinkEndpointCapabilities { @@ -64,7 +108,9 @@ func (e *endpoint) MaxHeaderLength() uint16 { return e.linkEP.MaxHeaderLength() + header.ARPSize } -func (e *endpoint) Close() {} +func (e *endpoint) Close() { + e.AddressableEndpointState.Cleanup() +} func (e *endpoint) WritePacket(*stack.Route, *stack.GSO, stack.NetworkHeaderParams, *stack.PacketBuffer) *tcpip.Error { return tcpip.ErrNotSupported @@ -85,6 +131,10 @@ func (e *endpoint) WriteHeaderIncludedPacket(r *stack.Route, pkt *stack.PacketBu } func (e *endpoint) HandlePacket(r *stack.Route, pkt *stack.PacketBuffer) { + if !e.isEnabled() { + return + } + h := header.ARP(pkt.NetworkHeader().View()) if !h.IsValid() { return @@ -95,15 +145,15 @@ func (e *endpoint) HandlePacket(r *stack.Route, pkt *stack.PacketBuffer) { localAddr := tcpip.Address(h.ProtocolAddressTarget()) if e.nud == nil { - if e.linkAddrCache.CheckLocalAddress(e.nicID, header.IPv4ProtocolNumber, localAddr) == 0 { + if e.linkAddrCache.CheckLocalAddress(e.NICID(), header.IPv4ProtocolNumber, localAddr) == 0 { return // we have no useful answer, ignore the request } addr := tcpip.Address(h.ProtocolAddressSender()) linkAddr := tcpip.LinkAddress(h.HardwareAddressSender()) - e.linkAddrCache.AddLinkAddress(e.nicID, addr, linkAddr) + e.linkAddrCache.AddLinkAddress(e.NICID(), addr, linkAddr) } else { - if r.Stack().CheckLocalAddress(e.nicID, header.IPv4ProtocolNumber, localAddr) == 0 { + if r.Stack().CheckLocalAddress(e.NICID(), header.IPv4ProtocolNumber, localAddr) == 0 { return // we have no useful answer, ignore the request } @@ -129,7 +179,7 @@ func (e *endpoint) HandlePacket(r *stack.Route, pkt *stack.PacketBuffer) { linkAddr := tcpip.LinkAddress(h.HardwareAddressSender()) if e.nud == nil { - e.linkAddrCache.AddLinkAddress(e.nicID, addr, linkAddr) + e.linkAddrCache.AddLinkAddress(e.NICID(), addr, linkAddr) return } @@ -161,14 +211,16 @@ func (*protocol) ParseAddresses(v buffer.View) (src, dst tcpip.Address) { return tcpip.Address(h.ProtocolAddressSender()), ProtocolAddress } -func (p *protocol) NewEndpoint(nicID tcpip.NICID, linkAddrCache stack.LinkAddressCache, nud stack.NUDHandler, dispatcher stack.TransportDispatcher, sender stack.LinkEndpoint, st *stack.Stack) stack.NetworkEndpoint { - return &endpoint{ +func (p *protocol) NewEndpoint(nic stack.NetworkInterface, linkAddrCache stack.LinkAddressCache, nud stack.NUDHandler, dispatcher stack.TransportDispatcher, sender stack.LinkEndpoint, st *stack.Stack) stack.NetworkEndpoint { + e := &endpoint{ protocol: p, - nicID: nicID, + nic: nic, linkEP: sender, linkAddrCache: linkAddrCache, nud: nud, } + e.AddressableEndpointState.Init(e) + return e } // LinkAddressProtocol implements stack.LinkAddressResolver.LinkAddressProtocol. diff --git a/pkg/tcpip/network/ipv4/ipv4.go b/pkg/tcpip/network/ipv4/ipv4.go index 254d66147..41f6914b9 100644 --- a/pkg/tcpip/network/ipv4/ipv4.go +++ b/pkg/tcpip/network/ipv4/ipv4.go @@ -19,6 +19,7 @@ import ( "fmt" "sync/atomic" + "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/tcpip" "gvisor.dev/gvisor/pkg/tcpip/buffer" "gvisor.dev/gvisor/pkg/tcpip/header" @@ -47,23 +48,118 @@ const ( fragmentblockSize = 8 ) +var ipv4BroadcastAddr = header.IPv4Broadcast.WithPrefix() + +var _ stack.GroupAddressableEndpoint = (*endpoint)(nil) +var _ stack.AddressableEndpoint = (*endpoint)(nil) +var _ stack.NetworkEndpoint = (*endpoint)(nil) + type endpoint struct { - nicID tcpip.NICID + nic stack.NetworkInterface linkEP stack.LinkEndpoint dispatcher stack.TransportDispatcher protocol *protocol stack *stack.Stack + + // enabled is set to 1 when the enpoint is enabled and 0 when it is + // disabled. + // + // Must be accessed using atomic operations. + enabled uint32 + + mu struct { + sync.RWMutex + + addressableEndpointState stack.AddressableEndpointState + } } // NewEndpoint creates a new ipv4 endpoint. -func (p *protocol) NewEndpoint(nicID tcpip.NICID, _ stack.LinkAddressCache, _ stack.NUDHandler, dispatcher stack.TransportDispatcher, linkEP stack.LinkEndpoint, st *stack.Stack) stack.NetworkEndpoint { - return &endpoint{ - nicID: nicID, +func (p *protocol) NewEndpoint(nic stack.NetworkInterface, _ stack.LinkAddressCache, _ stack.NUDHandler, dispatcher stack.TransportDispatcher, linkEP stack.LinkEndpoint, st *stack.Stack) stack.NetworkEndpoint { + e := &endpoint{ + nic: nic, linkEP: linkEP, dispatcher: dispatcher, protocol: p, stack: st, } + e.mu.addressableEndpointState.Init(e) + return e +} + +// Enable implements stack.NetworkEndpoint. +func (e *endpoint) Enable() *tcpip.Error { + e.mu.Lock() + defer e.mu.Unlock() + + // If the NIC is not enabled, the endpoint can't do anything meaningful so + // don't enable the endpoint. + if !e.nic.Enabled() { + return tcpip.ErrNotPermitted + } + + // If the endpoint is already enabled, there is nothing for it to do. + if !e.setEnabled(true) { + return nil + } + + // Create an endpoint to receive broadcast packets on this interface. + ep, err := e.mu.addressableEndpointState.AddAndAcquirePermanentAddress(ipv4BroadcastAddr, stack.NeverPrimaryEndpoint, stack.AddressConfigStatic, false /* deprecated */) + if err != nil { + return err + } + // We have no need for the address endpoint. + ep.DecRef() + + // As per RFC 1122 section 3.3.7, all hosts should join the all-hosts + // multicast group. Note, the IANA calls the all-hosts multicast group the + // all-systems multicast group. + _, err = e.mu.addressableEndpointState.JoinGroup(header.IPv4AllSystems) + return err +} + +// Enabled implements stack.NetworkEndpoint. +func (e *endpoint) Enabled() bool { + return e.nic.Enabled() && e.isEnabled() +} + +// isEnabled returns true if the endpoint is enabled, regardless of the +// enabled status of the NIC. +func (e *endpoint) isEnabled() bool { + return atomic.LoadUint32(&e.enabled) == 1 +} + +// setEnabled sets the enabled status for the endpoint. +// +// Returns true if the enabled status was updated. +func (e *endpoint) setEnabled(v bool) bool { + if v { + return atomic.SwapUint32(&e.enabled, 1) == 0 + } + return atomic.SwapUint32(&e.enabled, 0) == 1 +} + +// Disable implements stack.NetworkEndpoint. +func (e *endpoint) Disable() { + e.mu.Lock() + defer e.mu.Unlock() + e.disableLocked() +} + +func (e *endpoint) disableLocked() { + if !e.setEnabled(false) { + return + } + + // The endpoint may have already left the multicast group. + if _, err := e.mu.addressableEndpointState.LeaveGroup(header.IPv4AllSystems); err != nil && err != tcpip.ErrBadLocalAddress { + panic(fmt.Sprintf("unexpected error when leaving group = %s: %s", header.IPv4AllSystems, err)) + } + + // The address may have already been removed. + if err := e.mu.addressableEndpointState.RemovePermanentAddress(ipv4BroadcastAddr.Address); err != nil && err != tcpip.ErrBadLocalAddress { + panic(fmt.Sprintf("unexpected error when removing address = %s: %s", ipv4BroadcastAddr.Address, err)) + } } // DefaultTTL is the default time-to-live value for this endpoint. @@ -77,14 +173,14 @@ func (e *endpoint) MTU() uint32 { return calculateMTU(e.linkEP.MTU()) } -// Capabilities implements stack.NetworkEndpoint.Capabilities. +// Capabilities implements stack.NetworkEndpoint. func (e *endpoint) Capabilities() stack.LinkEndpointCapabilities { return e.linkEP.Capabilities() } // NICID returns the ID of the NIC this endpoint belongs to. func (e *endpoint) NICID() tcpip.NICID { - return e.nicID + return e.nic.ID() } // MaxHeaderLength returns the maximum length needed by ipv4 headers (and @@ -385,6 +481,10 @@ func (e *endpoint) WriteHeaderIncludedPacket(r *stack.Route, pkt *stack.PacketBu // HandlePacket is called by the link layer when new ipv4 packets arrive for // this endpoint. func (e *endpoint) HandlePacket(r *stack.Route, pkt *stack.PacketBuffer) { + if !e.isEnabled() { + return + } + h := header.IPv4(pkt.NetworkHeader().View()) if !h.IsValid(pkt.Data.Size() + pkt.NetworkHeader().View().Size() + pkt.TransportHeader().View().Size()) { r.Stats().IP.MalformedPacketsReceived.Increment() @@ -475,17 +575,123 @@ func (e *endpoint) HandlePacket(r *stack.Route, pkt *stack.PacketBuffer) { } // Close cleans up resources associated with the endpoint. -func (e *endpoint) Close() {} +func (e *endpoint) Close() { + e.mu.Lock() + defer e.mu.Unlock() -type protocol struct { - ids []uint32 - hashIV uint32 + e.disableLocked() + e.mu.addressableEndpointState.Cleanup() +} + +// AddAndAcquirePermanentAddress implements stack.AddressableEndpoint. +func (e *endpoint) AddAndAcquirePermanentAddress(addr tcpip.AddressWithPrefix, peb stack.PrimaryEndpointBehavior, configType stack.AddressConfigType, deprecated bool) (stack.AddressEndpoint, *tcpip.Error) { + e.mu.Lock() + defer e.mu.Unlock() + return e.mu.addressableEndpointState.AddAndAcquirePermanentAddress(addr, peb, configType, deprecated) +} + +// RemovePermanentAddress implements stack.AddressableEndpoint. +func (e *endpoint) RemovePermanentAddress(addr tcpip.Address) *tcpip.Error { + e.mu.Lock() + defer e.mu.Unlock() + return e.mu.addressableEndpointState.RemovePermanentAddress(addr) +} + +// AcquireAssignedAddress implements stack.AddressableEndpoint. +func (e *endpoint) AcquireAssignedAddress(localAddr tcpip.Address, allowTemp bool, tempPEB stack.PrimaryEndpointBehavior) stack.AddressEndpoint { + e.mu.Lock() + defer e.mu.Unlock() + + loopback := e.nic.IsLoopback() + addressEndpoint := e.mu.addressableEndpointState.ReadOnly().AddrOrMatching(localAddr, allowTemp, func(addressEndpoint stack.AddressEndpoint) bool { + subnet := addressEndpoint.AddressWithPrefix().Subnet() + // IPv4 has a notion of a subnet broadcast address and considers the + // loopback interface bound to an address's whole subnet (on linux). + return subnet.IsBroadcast(localAddr) || (loopback && subnet.Contains(localAddr)) + }) + if addressEndpoint != nil { + return addressEndpoint + } + + if !allowTemp { + return nil + } + addr := localAddr.WithPrefix() + addressEndpoint, err := e.mu.addressableEndpointState.AddAndAcquireTemporaryAddress(addr, tempPEB) + if err != nil { + // AddAddress only returns an error if the address is already assigned, + // but we just checked above if the address exists so we expect no error. + panic(fmt.Sprintf("e.mu.addressableEndpointState.AddAndAcquireTemporaryAddress(%s, %d): %s", addr, tempPEB, err)) + } + return addressEndpoint +} + +// AcquirePrimaryAddress implements stack.AddressableEndpoint. +func (e *endpoint) AcquirePrimaryAddress(remoteAddr tcpip.Address, allowExpired bool) stack.AddressEndpoint { + e.mu.RLock() + defer e.mu.RUnlock() + return e.mu.addressableEndpointState.AcquirePrimaryAddress(remoteAddr, allowExpired) +} + +// PrimaryAddresses implements stack.AddressableEndpoint. +func (e *endpoint) PrimaryAddresses() []tcpip.AddressWithPrefix { + e.mu.RLock() + defer e.mu.RUnlock() + return e.mu.addressableEndpointState.PrimaryAddresses() +} + +// PermanentAddresses implements stack.AddressableEndpoint. +func (e *endpoint) PermanentAddresses() []tcpip.AddressWithPrefix { + e.mu.RLock() + defer e.mu.RUnlock() + return e.mu.addressableEndpointState.PermanentAddresses() +} + +// JoinGroup implements stack.GroupAddressableEndpoint. +func (e *endpoint) JoinGroup(addr tcpip.Address) (bool, *tcpip.Error) { + if !header.IsV4MulticastAddress(addr) { + return false, tcpip.ErrBadAddress + } + + e.mu.Lock() + defer e.mu.Unlock() + return e.mu.addressableEndpointState.JoinGroup(addr) +} + +// LeaveGroup implements stack.GroupAddressableEndpoint. +func (e *endpoint) LeaveGroup(addr tcpip.Address) (bool, *tcpip.Error) { + e.mu.Lock() + defer e.mu.Unlock() + return e.mu.addressableEndpointState.LeaveGroup(addr) +} + +// IsInGroup implements stack.GroupAddressableEndpoint. +func (e *endpoint) IsInGroup(addr tcpip.Address) bool { + e.mu.RLock() + defer e.mu.RUnlock() + return e.mu.addressableEndpointState.IsInGroup(addr) +} + +var _ stack.ForwardingNetworkProtocol = (*protocol)(nil) +var _ stack.NetworkProtocol = (*protocol)(nil) + +type protocol struct { // defaultTTL is the current default TTL for the protocol. Only the - // uint8 portion of it is meaningful and it must be accessed - // atomically. + // uint8 portion of it is meaningful. + // + // Must be accessed using atomic operations. defaultTTL uint32 + // forwarding is set to 1 when the protocol has forwarding enabled and 0 + // when it is disabled. + // + // Must be accessed using atomic operations. + forwarding uint32 + + ids []uint32 + hashIV uint32 + fragmentation *fragmentation.Fragmentation } @@ -558,6 +764,20 @@ func (*protocol) Parse(pkt *stack.PacketBuffer) (proto tcpip.TransportProtocolNu return ipHdr.TransportProtocol(), !ipHdr.More() && ipHdr.FragmentOffset() == 0, true } +// Forwarding implements stack.ForwardingNetworkProtocol. +func (p *protocol) Forwarding() bool { + return uint8(atomic.LoadUint32(&p.forwarding)) == 1 +} + +// SetForwarding implements stack.ForwardingNetworkProtocol. +func (p *protocol) SetForwarding(v bool) { + if v { + atomic.StoreUint32(&p.forwarding, 1) + } else { + atomic.StoreUint32(&p.forwarding, 0) + } +} + // calculateMTU calculates the network-layer payload MTU based on the link-layer // payload mtu. func calculateMTU(mtu uint32) uint32 { diff --git a/pkg/tcpip/stack/dhcpv6configurationfromndpra_string.go b/pkg/tcpip/network/ipv6/dhcpv6configurationfromndpra_string.go index d199ded6a..09ba133b1 100644 --- a/pkg/tcpip/stack/dhcpv6configurationfromndpra_string.go +++ b/pkg/tcpip/network/ipv6/dhcpv6configurationfromndpra_string.go @@ -14,7 +14,7 @@ // Code generated by "stringer -type DHCPv6ConfigurationFromNDPRA"; DO NOT EDIT. -package stack +package ipv6 import "strconv" diff --git a/pkg/tcpip/network/ipv6/icmp.go b/pkg/tcpip/network/ipv6/icmp.go index dd3295b31..270439b5c 100644 --- a/pkg/tcpip/network/ipv6/icmp.go +++ b/pkg/tcpip/network/ipv6/icmp.go @@ -15,6 +15,8 @@ package ipv6 import ( + "fmt" + "gvisor.dev/gvisor/pkg/tcpip" "gvisor.dev/gvisor/pkg/tcpip/buffer" "gvisor.dev/gvisor/pkg/tcpip/header" @@ -207,14 +209,7 @@ func (e *endpoint) handleICMP(r *stack.Route, pkt *stack.PacketBuffer, hasFragme return } - s := r.Stack() - if isTentative, err := s.IsAddrTentative(e.nicID, targetAddr); err != nil { - // We will only get an error if the NIC is unrecognized, which should not - // happen. For now, drop this packet. - // - // TODO(b/141002840): Handle this better? - return - } else if isTentative { + if e.hasTentativeAddr(targetAddr) { // If the target address is tentative and the source of the packet is a // unicast (specified) address, then the source of the packet is // attempting to perform address resolution on the target. In this case, @@ -227,7 +222,20 @@ func (e *endpoint) handleICMP(r *stack.Route, pkt *stack.PacketBuffer, hasFragme // stack know so it can handle such a scenario and do nothing further with // the NS. if r.RemoteAddress == header.IPv6Any { - s.DupTentativeAddrDetected(e.nicID, targetAddr) + // We would get an error if the address no longer exists or the address + // is no longer tentative (DAD resolved between the call to + // hasTentativeAddr and this point). Both of these are valid scenarios: + // 1) An address may be removed at any time. + // 2) As per RFC 4862 section 5.4, DAD is not a perfect: + // "Note that the method for detecting duplicates + // is not completely reliable, and it is possible that duplicate + // addresses will still exist" + // + // TODO(gvisor.dev/issue/4046): Handle the scenario when a duplicate + // address is detected for an assigned address. + if err := e.dupTentativeAddrDetected(targetAddr); err != nil && err != tcpip.ErrBadAddress && err != tcpip.ErrInvalidEndpointState { + panic(fmt.Sprintf("unexpected error handling duplicate tentative address: %s", err)) + } } // Do not handle neighbor solicitations targeted to an address that is @@ -240,7 +248,7 @@ func (e *endpoint) handleICMP(r *stack.Route, pkt *stack.PacketBuffer, hasFragme // section 5.4.3. // Is the NS targeting us? - if s.CheckLocalAddress(e.nicID, ProtocolNumber, targetAddr) == 0 { + if r.Stack().CheckLocalAddress(e.NICID(), ProtocolNumber, targetAddr) == 0 { return } @@ -275,7 +283,7 @@ func (e *endpoint) handleICMP(r *stack.Route, pkt *stack.PacketBuffer, hasFragme } else if e.nud != nil { e.nud.HandleProbe(r.RemoteAddress, r.LocalAddress, header.IPv6ProtocolNumber, sourceLinkAddr, e.protocol) } else { - e.linkAddrCache.AddLinkAddress(e.nicID, r.RemoteAddress, sourceLinkAddr) + e.linkAddrCache.AddLinkAddress(e.NICID(), r.RemoteAddress, sourceLinkAddr) } // ICMPv6 Neighbor Solicit messages are always sent to @@ -353,20 +361,26 @@ func (e *endpoint) handleICMP(r *stack.Route, pkt *stack.PacketBuffer, hasFragme // NDP datagrams are very small and ToView() will not incur allocations. na := header.NDPNeighborAdvert(payload.ToView()) targetAddr := na.TargetAddress() - s := r.Stack() - - if isTentative, err := s.IsAddrTentative(e.nicID, targetAddr); err != nil { - // We will only get an error if the NIC is unrecognized, which should not - // happen. For now short-circuit this packet. - // - // TODO(b/141002840): Handle this better? - return - } else if isTentative { + if e.hasTentativeAddr(targetAddr) { // We just got an NA from a node that owns an address we are performing // DAD on, implying the address is not unique. In this case we let the // stack know so it can handle such a scenario and do nothing furthur with // the NDP NA. - s.DupTentativeAddrDetected(e.nicID, targetAddr) + // + // We would get an error if the address no longer exists or the address + // is no longer tentative (DAD resolved between the call to + // hasTentativeAddr and this point). Both of these are valid scenarios: + // 1) An address may be removed at any time. + // 2) As per RFC 4862 section 5.4, DAD is not a perfect: + // "Note that the method for detecting duplicates + // is not completely reliable, and it is possible that duplicate + // addresses will still exist" + // + // TODO(gvisor.dev/issue/4046): Handle the scenario when a duplicate + // address is detected for an assigned address. + if err := e.dupTentativeAddrDetected(targetAddr); err != nil && err != tcpip.ErrBadAddress && err != tcpip.ErrInvalidEndpointState { + panic(fmt.Sprintf("unexpected error handling duplicate tentative address: %s", err)) + } return } @@ -396,7 +410,7 @@ func (e *endpoint) handleICMP(r *stack.Route, pkt *stack.PacketBuffer, hasFragme // address cache with the link address for the target of the message. if len(targetLinkAddr) != 0 { if e.nud == nil { - e.linkAddrCache.AddLinkAddress(e.nicID, targetAddr, targetLinkAddr) + e.linkAddrCache.AddLinkAddress(e.NICID(), targetAddr, targetLinkAddr) return } @@ -568,9 +582,9 @@ func (e *endpoint) handleICMP(r *stack.Route, pkt *stack.PacketBuffer, hasFragme e.nud.HandleProbe(routerAddr, r.LocalAddress, header.IPv6ProtocolNumber, sourceLinkAddr, e.protocol) } - // Tell the NIC to handle the RA. - stack := r.Stack() - stack.HandleNDPRA(e.nicID, routerAddr, ra) + e.mu.Lock() + e.mu.ndp.handleRA(routerAddr, ra) + e.mu.Unlock() case header.ICMPv6RedirectMsg: // TODO(gvisor.dev/issue/2285): Call `e.nud.HandleProbe` after validating diff --git a/pkg/tcpip/network/ipv6/ipv6.go b/pkg/tcpip/network/ipv6/ipv6.go index e436c6a9e..75b27a4cf 100644 --- a/pkg/tcpip/network/ipv6/ipv6.go +++ b/pkg/tcpip/network/ipv6/ipv6.go @@ -17,8 +17,10 @@ package ipv6 import ( "fmt" + "sort" "sync/atomic" + "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/tcpip" "gvisor.dev/gvisor/pkg/tcpip/buffer" "gvisor.dev/gvisor/pkg/tcpip/header" @@ -40,14 +42,302 @@ const ( DefaultTTL = 64 ) +var _ stack.GroupAddressableEndpoint = (*endpoint)(nil) +var _ stack.AddressableEndpoint = (*endpoint)(nil) +var _ stack.NetworkEndpoint = (*endpoint)(nil) +var _ stack.NDPEndpoint = (*endpoint)(nil) +var _ NDPEndpoint = (*endpoint)(nil) + type endpoint struct { - nicID tcpip.NICID + nic stack.NetworkInterface linkEP stack.LinkEndpoint linkAddrCache stack.LinkAddressCache nud stack.NUDHandler dispatcher stack.TransportDispatcher protocol *protocol stack *stack.Stack + + // enabled is set to 1 when the endpoint is enabled and 0 when it is + // disabled. + // + // Must be accessed using atomic operations. + enabled uint32 + + mu struct { + sync.RWMutex + + addressableEndpointState stack.AddressableEndpointState + ndp ndpState + } +} + +// NICNameFromID is a function that returns a stable name for the specified NIC, +// even if different NIC IDs are used to refer to the same NIC in different +// program runs. It is used when generating opaque interface identifiers (IIDs). +// If the NIC was created with a name, it is passed to NICNameFromID. +// +// NICNameFromID SHOULD return unique NIC names so unique opaque IIDs are +// generated for the same prefix on differnt NICs. +type NICNameFromID func(tcpip.NICID, string) string + +// OpaqueInterfaceIdentifierOptions holds the options related to the generation +// of opaque interface indentifiers (IIDs) as defined by RFC 7217. +type OpaqueInterfaceIdentifierOptions struct { + // NICNameFromID is a function that returns a stable name for a specified NIC, + // even if the NIC ID changes over time. + // + // Must be specified to generate the opaque IID. + NICNameFromID NICNameFromID + + // SecretKey is a pseudo-random number used as the secret key when generating + // opaque IIDs as defined by RFC 7217. The key SHOULD be at least + // header.OpaqueIIDSecretKeyMinBytes bytes and MUST follow minimum randomness + // requirements for security as outlined by RFC 4086. SecretKey MUST NOT + // change between program runs, unless explicitly changed. + // + // OpaqueInterfaceIdentifierOptions takes ownership of SecretKey. SecretKey + // MUST NOT be modified after Stack is created. + // + // May be nil, but a nil value is highly discouraged to maintain + // some level of randomness between nodes. + SecretKey []byte +} + +// InvalidateDefaultRouter implements stack.NDPEndpoint. +func (e *endpoint) InvalidateDefaultRouter(rtr tcpip.Address) { + e.mu.Lock() + defer e.mu.Unlock() + e.mu.ndp.invalidateDefaultRouter(rtr) +} + +// SetNDPConfigurations implements NDPEndpoint. +func (e *endpoint) SetNDPConfigurations(c NDPConfigurations) { + c.validate() + e.mu.Lock() + defer e.mu.Unlock() + e.mu.ndp.configs = c +} + +// hasTentativeAddr returns true if addr is tentative on e. +func (e *endpoint) hasTentativeAddr(addr tcpip.Address) bool { + e.mu.RLock() + addressEndpoint := e.getAddressRLocked(addr) + e.mu.RUnlock() + return addressEndpoint != nil && addressEndpoint.GetKind() == stack.PermanentTentative +} + +// dupTentativeAddrDetected attempts to inform e that a tentative addr is a +// duplicate on a link. +// +// dupTentativeAddrDetected removes the tentative address if it exists. If the +// address was generated via SLAAC, an attempt is made to generate a new +// address. +func (e *endpoint) dupTentativeAddrDetected(addr tcpip.Address) *tcpip.Error { + e.mu.Lock() + defer e.mu.Unlock() + + addressEndpoint := e.getAddressRLocked(addr) + if addressEndpoint == nil { + return tcpip.ErrBadAddress + } + + if addressEndpoint.GetKind() != stack.PermanentTentative { + return tcpip.ErrInvalidEndpointState + } + + // If the address is a SLAAC address, do not invalidate its SLAAC prefix as an + // attempt will be made to generate a new address for it. + if err := e.removePermanentEndpointLocked(addressEndpoint, false /* allowSLAACInvalidation */); err != nil { + return err + } + + prefix := addressEndpoint.AddressWithPrefix().Subnet() + + switch t := addressEndpoint.ConfigType(); t { + case stack.AddressConfigStatic: + case stack.AddressConfigSlaac: + e.mu.ndp.regenerateSLAACAddr(prefix) + case stack.AddressConfigSlaacTemp: + // Do not reset the generation attempts counter for the prefix as the + // temporary address is being regenerated in response to a DAD conflict. + e.mu.ndp.regenerateTempSLAACAddr(prefix, false /* resetGenAttempts */) + default: + panic(fmt.Sprintf("unrecognized address config type = %d", t)) + } + + return nil +} + +// transitionForwarding transitions the endpoint's forwarding status to +// forwarding. +// +// Must only be called when the forwarding status changes. +func (e *endpoint) transitionForwarding(forwarding bool) { + e.mu.Lock() + defer e.mu.Unlock() + + if !e.Enabled() { + return + } + + if forwarding { + // When transitioning into an IPv6 router, host-only state (NDP discovered + // routers, discovered on-link prefixes, and auto-generated addresses) is + // cleaned up/invalidated and NDP router solicitations are stopped. + e.mu.ndp.stopSolicitingRouters() + e.mu.ndp.cleanupState(true /* hostOnly */) + } else { + // When transitioning into an IPv6 host, NDP router solicitations are + // started. + e.mu.ndp.startSolicitingRouters() + } +} + +// Enable implements stack.NetworkEndpoint. +func (e *endpoint) Enable() *tcpip.Error { + e.mu.Lock() + defer e.mu.Unlock() + + // If the NIC is not enabled, the endpoint can't do anything meaningful so + // don't enable the endpoint. + if !e.nic.Enabled() { + return tcpip.ErrNotPermitted + } + + // If the endpoint is already enabled, there is nothing for it to do. + if !e.setEnabled(true) { + return nil + } + + // Join the IPv6 All-Nodes Multicast group if the stack is configured to + // use IPv6. This is required to ensure that this node properly receives + // and responds to the various NDP messages that are destined to the + // all-nodes multicast address. An example is the Neighbor Advertisement + // when we perform Duplicate Address Detection, or Router Advertisement + // when we do Router Discovery. See RFC 4862, section 5.4.2 and RFC 4861 + // section 4.2 for more information. + // + // Also auto-generate an IPv6 link-local address based on the endpoint's + // link address if it is configured to do so. Note, each interface is + // required to have IPv6 link-local unicast address, as per RFC 4291 + // section 2.1. + + // Join the All-Nodes multicast group before starting DAD as responses to DAD + // (NDP NS) messages may be sent to the All-Nodes multicast group if the + // source address of the NDP NS is the unspecified address, as per RFC 4861 + // section 7.2.4. + if _, err := e.mu.addressableEndpointState.JoinGroup(header.IPv6AllNodesMulticastAddress); err != nil { + return err + } + + // Perform DAD on the all the unicast IPv6 endpoints that are in the permanent + // state. + // + // Addresses may have aleady completed DAD but in the time since the endpoint + // was last enabled, other devices may have acquired the same addresses. + var err *tcpip.Error + e.mu.addressableEndpointState.ReadOnly().ForEach(func(addressEndpoint stack.AddressEndpoint) bool { + addr := addressEndpoint.AddressWithPrefix().Address + if !header.IsV6UnicastAddress(addr) { + return true + } + + switch addressEndpoint.GetKind() { + case stack.Permanent: + addressEndpoint.SetKind(stack.PermanentTentative) + fallthrough + case stack.PermanentTentative: + err = e.mu.ndp.startDuplicateAddressDetection(addr, addressEndpoint) + return err == nil + default: + return true + } + }) + if err != nil { + return err + } + + // Do not auto-generate an IPv6 link-local address for loopback devices. + if e.protocol.autoGenIPv6LinkLocal { + // The valid and preferred lifetime is infinite for the auto-generated + // link-local address. + e.mu.ndp.doSLAAC(header.IPv6LinkLocalPrefix.Subnet(), header.NDPInfiniteLifetime, header.NDPInfiniteLifetime) + } + + // If we are operating as a router, then do not solicit routers since we + // won't process the RAs anyway. + // + // Routers do not process Router Advertisements (RA) the same way a host + // does. That is, routers do not learn from RAs (e.g. on-link prefixes + // and default routers). Therefore, soliciting RAs from other routers on + // a link is unnecessary for routers. + if !e.protocol.Forwarding() { + e.mu.ndp.startSolicitingRouters() + } + + return nil +} + +// Enabled implements stack.NetworkEndpoint. +func (e *endpoint) Enabled() bool { + return e.nic.Enabled() && e.isEnabled() +} + +// isEnabled returns true if the endpoint is enabled, regardless of the +// enabled status of the NIC. +func (e *endpoint) isEnabled() bool { + return atomic.LoadUint32(&e.enabled) == 1 +} + +// setEnabled sets the enabled status for the endpoint. +// +// Returns true if the enabled status was updated. +func (e *endpoint) setEnabled(v bool) bool { + if v { + return atomic.SwapUint32(&e.enabled, 1) == 0 + } + return atomic.SwapUint32(&e.enabled, 0) == 1 +} + +// Disable implements stack.NetworkEndpoint. +func (e *endpoint) Disable() { + e.mu.Lock() + defer e.mu.Unlock() + e.disableLocked() +} + +func (e *endpoint) disableLocked() { + if !e.setEnabled(false) { + return + } + + e.mu.ndp.stopSolicitingRouters() + e.mu.ndp.cleanupState(false /* hostOnly */) + e.stopDADForPermanentAddressesLocked() + + // The endpoint may have already left the multicast group. + if _, err := e.mu.addressableEndpointState.LeaveGroup(header.IPv6AllNodesMulticastAddress); err != nil && err != tcpip.ErrBadLocalAddress { + panic(fmt.Sprintf("unexpected error when leaving group = %s: %s", header.IPv6AllNodesMulticastAddress, err)) + } +} + +// stopDADForPermanentAddressesLocked stops DAD for all permaneent addresses. +// +// Precondition: e.mu must be write locked. +func (e *endpoint) stopDADForPermanentAddressesLocked() { + // Stop DAD for all the tentative unicast addresses. + e.mu.addressableEndpointState.ReadOnly().ForEach(func(addressEndpoint stack.AddressEndpoint) bool { + if addressEndpoint.GetKind() != stack.PermanentTentative { + return true + } + + addr := addressEndpoint.AddressWithPrefix().Address + if header.IsV6UnicastAddress(addr) { + e.mu.ndp.stopDuplicateAddressDetection(addr) + } + + return true + }) } // DefaultTTL is the default hop limit for this endpoint. @@ -63,10 +353,10 @@ func (e *endpoint) MTU() uint32 { // NICID returns the ID of the NIC this endpoint belongs to. func (e *endpoint) NICID() tcpip.NICID { - return e.nicID + return e.nic.ID() } -// Capabilities implements stack.NetworkEndpoint.Capabilities. +// Capabilities implements stack.NetworkEndpoint. func (e *endpoint) Capabilities() stack.LinkEndpointCapabilities { return e.linkEP.Capabilities() } @@ -219,6 +509,10 @@ func (*endpoint) WriteHeaderIncludedPacket(r *stack.Route, pkt *stack.PacketBuff // HandlePacket is called by the link layer when new ipv6 packets arrive for // this endpoint. func (e *endpoint) HandlePacket(r *stack.Route, pkt *stack.PacketBuffer) { + if !e.isEnabled() { + return + } + h := header.IPv6(pkt.NetworkHeader().View()) if !h.IsValid(pkt.Data.Size() + pkt.NetworkHeader().View().Size() + pkt.TransportHeader().View().Size()) { r.Stats().IP.MalformedPacketsReceived.Increment() @@ -236,7 +530,7 @@ func (e *endpoint) HandlePacket(r *stack.Route, pkt *stack.PacketBuffer) { hasFragmentHeader := false // iptables filtering. All packets that reach here are intended for - // this machine and will not be forwarded. + // this machine and need not be forwarded. ipt := e.stack.IPTables() if ok := ipt.Check(stack.Input, pkt, nil, nil, "", ""); !ok { // iptables is telling us to drop the packet. @@ -504,19 +798,331 @@ func (e *endpoint) HandlePacket(r *stack.Route, pkt *stack.PacketBuffer) { } // Close cleans up resources associated with the endpoint. -func (*endpoint) Close() {} +func (e *endpoint) Close() { + e.mu.Lock() + e.disableLocked() + e.mu.ndp.removeSLAACAddresses(false /* keepLinkLocal */) + e.stopDADForPermanentAddressesLocked() + e.mu.addressableEndpointState.Cleanup() + e.mu.Unlock() + + e.protocol.forgetEndpoint(e) +} // NetworkProtocolNumber implements stack.NetworkEndpoint.NetworkProtocolNumber. func (e *endpoint) NetworkProtocolNumber() tcpip.NetworkProtocolNumber { return e.protocol.Number() } +// AddAndAcquirePermanentAddress implements stack.AddressableEndpoint. +func (e *endpoint) AddAndAcquirePermanentAddress(addr tcpip.AddressWithPrefix, peb stack.PrimaryEndpointBehavior, configType stack.AddressConfigType, deprecated bool) (stack.AddressEndpoint, *tcpip.Error) { + // TODO(b/169350103): add checks here after making sure we no longer receive + // an empty address. + e.mu.Lock() + defer e.mu.Unlock() + return e.addAndAcquirePermanentAddressLocked(addr, peb, configType, deprecated) +} + +// addAndAcquirePermanentAddressLocked is like AddAndAcquirePermanentAddress but +// with locking requirements. +// +// addAndAcquirePermanentAddressLocked also joins the passed address's +// solicited-node multicast group and start duplicate address detection. +// +// Precondition: e.mu must be write locked. +func (e *endpoint) addAndAcquirePermanentAddressLocked(addr tcpip.AddressWithPrefix, peb stack.PrimaryEndpointBehavior, configType stack.AddressConfigType, deprecated bool) (stack.AddressEndpoint, *tcpip.Error) { + addressEndpoint, err := e.mu.addressableEndpointState.AddAndAcquirePermanentAddress(addr, peb, configType, deprecated) + if err != nil { + return nil, err + } + + if !header.IsV6UnicastAddress(addr.Address) { + return addressEndpoint, nil + } + + snmc := header.SolicitedNodeAddr(addr.Address) + if _, err := e.mu.addressableEndpointState.JoinGroup(snmc); err != nil { + return nil, err + } + + addressEndpoint.SetKind(stack.PermanentTentative) + + if e.Enabled() { + if err := e.mu.ndp.startDuplicateAddressDetection(addr.Address, addressEndpoint); err != nil { + return nil, err + } + } + + return addressEndpoint, nil +} + +// RemovePermanentAddress implements stack.AddressableEndpoint. +func (e *endpoint) RemovePermanentAddress(addr tcpip.Address) *tcpip.Error { + e.mu.Lock() + defer e.mu.Unlock() + + addressEndpoint := e.getAddressRLocked(addr) + if addressEndpoint == nil || !addressEndpoint.GetKind().IsPermanent() { + return tcpip.ErrBadLocalAddress + } + + return e.removePermanentEndpointLocked(addressEndpoint, true) +} + +// removePermanentEndpointLocked is like removePermanentAddressLocked except +// it works with a stack.AddressEndpoint. +// +// Precondition: e.mu must be write locked. +func (e *endpoint) removePermanentEndpointLocked(addressEndpoint stack.AddressEndpoint, allowSLAACInvalidation bool) *tcpip.Error { + addr := addressEndpoint.AddressWithPrefix() + unicast := header.IsV6UnicastAddress(addr.Address) + if unicast { + e.mu.ndp.stopDuplicateAddressDetection(addr.Address) + + // If we are removing an address generated via SLAAC, cleanup + // its SLAAC resources and notify the integrator. + switch addressEndpoint.ConfigType() { + case stack.AddressConfigSlaac: + e.mu.ndp.cleanupSLAACAddrResourcesAndNotify(addr, allowSLAACInvalidation) + case stack.AddressConfigSlaacTemp: + e.mu.ndp.cleanupTempSLAACAddrResourcesAndNotify(addr, allowSLAACInvalidation) + } + } + + if err := e.mu.addressableEndpointState.RemovePermanentEndpoint(addressEndpoint); err != nil { + return err + } + + if !unicast { + return nil + } + + snmc := header.SolicitedNodeAddr(addr.Address) + if _, err := e.mu.addressableEndpointState.LeaveGroup(snmc); err != nil && err != tcpip.ErrBadLocalAddress { + return err + } + + return nil +} + +// hasPermanentAddressLocked returns true if the endpoint has a permanent +// address equal to the passed address. +// +// Precondition: e.mu must be read or write locked. +func (e *endpoint) hasPermanentAddressRLocked(addr tcpip.Address) bool { + addressEndpoint := e.getAddressRLocked(addr) + if addressEndpoint == nil { + return false + } + return addressEndpoint.GetKind().IsPermanent() +} + +// getAddressRLocked returns the endpoint for the passed address. +// +// Precondition: e.mu must be read or write locked. +func (e *endpoint) getAddressRLocked(localAddr tcpip.Address) stack.AddressEndpoint { + return e.mu.addressableEndpointState.ReadOnly().Lookup(localAddr) +} + +// AcquireAssignedAddress implements stack.AddressableEndpoint. +func (e *endpoint) AcquireAssignedAddress(localAddr tcpip.Address, allowTemp bool, tempPEB stack.PrimaryEndpointBehavior) stack.AddressEndpoint { + e.mu.Lock() + defer e.mu.Unlock() + return e.acquireAddressOrCreateTempLocked(localAddr, allowTemp, tempPEB) +} + +// acquireAddressOrCreateTempLocked is like AcquireAssignedAddress but with +// locking requirements. +// +// Precondition: e.mu must be write locked. +func (e *endpoint) acquireAddressOrCreateTempLocked(localAddr tcpip.Address, allowTemp bool, tempPEB stack.PrimaryEndpointBehavior) stack.AddressEndpoint { + return e.mu.addressableEndpointState.AcquireAssignedAddress(localAddr, allowTemp, tempPEB) +} + +// AcquirePrimaryAddress implements stack.AddressableEndpoint. +func (e *endpoint) AcquirePrimaryAddress(remoteAddr tcpip.Address, allowExpired bool) stack.AddressEndpoint { + e.mu.RLock() + defer e.mu.RUnlock() + return e.acquirePrimaryAddressRLocked(remoteAddr, allowExpired) +} + +// acquirePrimaryAddressRLocked is like AcquirePrimaryAddress but with locking +// requirements. +// +// Precondition: e.mu must be read locked. +func (e *endpoint) acquirePrimaryAddressRLocked(remoteAddr tcpip.Address, allowExpired bool) stack.AddressEndpoint { + // addrCandidate is a candidate for Source Address Selection, as per + // RFC 6724 section 5. + type addrCandidate struct { + addressEndpoint stack.AddressEndpoint + scope header.IPv6AddressScope + } + + if len(remoteAddr) == 0 { + return e.mu.addressableEndpointState.AcquirePrimaryAddress(remoteAddr, allowExpired) + } + + // Create a candidate set of available addresses we can potentially use as a + // source address. + var cs []addrCandidate + e.mu.addressableEndpointState.ReadOnly().ForEachPrimaryEndpoint(func(addressEndpoint stack.AddressEndpoint) { + // If r is not valid for outgoing connections, it is not a valid endpoint. + if !addressEndpoint.IsAssigned(allowExpired) { + return + } + + addr := addressEndpoint.AddressWithPrefix().Address + scope, err := header.ScopeForIPv6Address(addr) + if err != nil { + // Should never happen as we got r from the primary IPv6 endpoint list and + // ScopeForIPv6Address only returns an error if addr is not an IPv6 + // address. + panic(fmt.Sprintf("header.ScopeForIPv6Address(%s): %s", addr, err)) + } + + cs = append(cs, addrCandidate{ + addressEndpoint: addressEndpoint, + scope: scope, + }) + }) + + remoteScope, err := header.ScopeForIPv6Address(remoteAddr) + if err != nil { + // primaryIPv6Endpoint should never be called with an invalid IPv6 address. + panic(fmt.Sprintf("header.ScopeForIPv6Address(%s): %s", remoteAddr, err)) + } + + // Sort the addresses as per RFC 6724 section 5 rules 1-3. + // + // TODO(b/146021396): Implement rules 4-8 of RFC 6724 section 5. + sort.Slice(cs, func(i, j int) bool { + sa := cs[i] + sb := cs[j] + + // Prefer same address as per RFC 6724 section 5 rule 1. + if sa.addressEndpoint.AddressWithPrefix().Address == remoteAddr { + return true + } + if sb.addressEndpoint.AddressWithPrefix().Address == remoteAddr { + return false + } + + // Prefer appropriate scope as per RFC 6724 section 5 rule 2. + if sa.scope < sb.scope { + return sa.scope >= remoteScope + } else if sb.scope < sa.scope { + return sb.scope < remoteScope + } + + // Avoid deprecated addresses as per RFC 6724 section 5 rule 3. + if saDep, sbDep := sa.addressEndpoint.Deprecated(), sb.addressEndpoint.Deprecated(); saDep != sbDep { + // If sa is not deprecated, it is preferred over sb. + return sbDep + } + + // Prefer temporary addresses as per RFC 6724 section 5 rule 7. + if saTemp, sbTemp := sa.addressEndpoint.ConfigType() == stack.AddressConfigSlaacTemp, sb.addressEndpoint.ConfigType() == stack.AddressConfigSlaacTemp; saTemp != sbTemp { + return saTemp + } + + // sa and sb are equal, return the endpoint that is closest to the front of + // the primary endpoint list. + return i < j + }) + + // Return the most preferred address that can have its reference count + // incremented. + for _, c := range cs { + if c.addressEndpoint.IncRef() { + return c.addressEndpoint + } + } + + return nil +} + +// PrimaryAddresses implements stack.AddressableEndpoint. +func (e *endpoint) PrimaryAddresses() []tcpip.AddressWithPrefix { + e.mu.RLock() + defer e.mu.RUnlock() + return e.mu.addressableEndpointState.PrimaryAddresses() +} + +// PermanentAddresses implements stack.AddressableEndpoint. +func (e *endpoint) PermanentAddresses() []tcpip.AddressWithPrefix { + e.mu.RLock() + defer e.mu.RUnlock() + return e.mu.addressableEndpointState.PermanentAddresses() +} + +// JoinGroup implements stack.GroupAddressableEndpoint. +func (e *endpoint) JoinGroup(addr tcpip.Address) (bool, *tcpip.Error) { + if !header.IsV6MulticastAddress(addr) { + return false, tcpip.ErrBadAddress + } + + e.mu.Lock() + defer e.mu.Unlock() + return e.mu.addressableEndpointState.JoinGroup(addr) +} + +// LeaveGroup implements stack.GroupAddressableEndpoint. +func (e *endpoint) LeaveGroup(addr tcpip.Address) (bool, *tcpip.Error) { + e.mu.Lock() + defer e.mu.Unlock() + return e.mu.addressableEndpointState.LeaveGroup(addr) +} + +// IsInGroup implements stack.GroupAddressableEndpoint. +func (e *endpoint) IsInGroup(addr tcpip.Address) bool { + e.mu.RLock() + defer e.mu.RUnlock() + return e.mu.addressableEndpointState.IsInGroup(addr) +} + +var _ stack.ForwardingNetworkProtocol = (*protocol)(nil) +var _ stack.NetworkProtocol = (*protocol)(nil) + type protocol struct { + mu struct { + sync.RWMutex + + eps map[*endpoint]struct{} + } + // defaultTTL is the current default TTL for the protocol. Only the - // uint8 portion of it is meaningful and it must be accessed - // atomically. - defaultTTL uint32 + // uint8 portion of it is meaningful. + // + // Must be accessed using atomic operations. + defaultTTL uint32 + + // forwarding is set to 1 when the protocol has forwarding enabled and 0 + // when it is disabled. + // + // Must be accessed using atomic operations. + forwarding uint32 + fragmentation *fragmentation.Fragmentation + + // ndpDisp is the NDP event dispatcher that is used to send the netstack + // integrator NDP related events. + ndpDisp NDPDispatcher + + // ndpConfigs is the default NDP configurations used by an IPv6 endpoint. + ndpConfigs NDPConfigurations + + // opaqueIIDOpts hold the options for generating opaque interface identifiers + // (IIDs) as outlined by RFC 7217. + opaqueIIDOpts OpaqueInterfaceIdentifierOptions + + // tempIIDSeed is used to seed the initial temporary interface identifier + // history value used to generate IIDs for temporary SLAAC addresses. + tempIIDSeed []byte + + // autoGenIPv6LinkLocal determines whether or not the stack attempts to + // auto-generate an IPv6 link-local address for newly enabled non-loopback + // NICs. See the AutoGenIPv6LinkLocal field of Options for more details. + autoGenIPv6LinkLocal bool } // Number returns the ipv6 protocol number. @@ -541,9 +1147,9 @@ func (*protocol) ParseAddresses(v buffer.View) (src, dst tcpip.Address) { } // NewEndpoint creates a new ipv6 endpoint. -func (p *protocol) NewEndpoint(nicID tcpip.NICID, linkAddrCache stack.LinkAddressCache, nud stack.NUDHandler, dispatcher stack.TransportDispatcher, linkEP stack.LinkEndpoint, st *stack.Stack) stack.NetworkEndpoint { - return &endpoint{ - nicID: nicID, +func (p *protocol) NewEndpoint(nic stack.NetworkInterface, linkAddrCache stack.LinkAddressCache, nud stack.NUDHandler, dispatcher stack.TransportDispatcher, linkEP stack.LinkEndpoint, st *stack.Stack) stack.NetworkEndpoint { + e := &endpoint{ + nic: nic, linkEP: linkEP, linkAddrCache: linkAddrCache, nud: nud, @@ -551,6 +1157,27 @@ func (p *protocol) NewEndpoint(nicID tcpip.NICID, linkAddrCache stack.LinkAddres protocol: p, stack: st, } + e.mu.addressableEndpointState.Init(e) + e.mu.ndp = ndpState{ + ep: e, + configs: p.ndpConfigs, + dad: make(map[tcpip.Address]dadState), + defaultRouters: make(map[tcpip.Address]defaultRouterState), + onLinkPrefixes: make(map[tcpip.Subnet]onLinkPrefixState), + slaacPrefixes: make(map[tcpip.Subnet]slaacPrefixState), + } + e.mu.ndp.initializeTempAddrState() + + p.mu.Lock() + defer p.mu.Unlock() + p.mu.eps[e] = struct{}{} + return e +} + +func (p *protocol) forgetEndpoint(e *endpoint) { + p.mu.Lock() + defer p.mu.Unlock() + delete(p.mu.eps, e) } // SetOption implements NetworkProtocol.SetOption. @@ -601,6 +1228,35 @@ func (*protocol) Parse(pkt *stack.PacketBuffer) (proto tcpip.TransportProtocolNu return proto, !fragMore && fragOffset == 0, true } +// Forwarding implements stack.ForwardingNetworkProtocol. +func (p *protocol) Forwarding() bool { + return uint8(atomic.LoadUint32(&p.forwarding)) == 1 +} + +// setForwarding sets the forwarding status for the protocol. +// +// Returns true if the forwarding status was updated. +func (p *protocol) setForwarding(v bool) bool { + if v { + return atomic.SwapUint32(&p.forwarding, 1) == 0 + } + return atomic.SwapUint32(&p.forwarding, 0) == 1 +} + +// SetForwarding implements stack.ForwardingNetworkProtocol. +func (p *protocol) SetForwarding(v bool) { + p.mu.Lock() + defer p.mu.Unlock() + + if !p.setForwarding(v) { + return + } + + for ep := range p.mu.eps { + ep.transitionForwarding(v) + } +} + // calculateMTU calculates the network-layer payload MTU based on the link-layer // payload mtu. func calculateMTU(mtu uint32) uint32 { @@ -611,10 +1267,68 @@ func calculateMTU(mtu uint32) uint32 { return maxPayloadSize } -// NewProtocol returns an IPv6 network protocol. -func NewProtocol(*stack.Stack) stack.NetworkProtocol { - return &protocol{ - defaultTTL: DefaultTTL, - fragmentation: fragmentation.NewFragmentation(header.IPv6FragmentExtHdrFragmentOffsetBytesPerUnit, fragmentation.HighFragThreshold, fragmentation.LowFragThreshold, fragmentation.DefaultReassembleTimeout), +// Options holds options to configure a new protocol. +type Options struct { + // NDPConfigs is the default NDP configurations used by interfaces. + NDPConfigs NDPConfigurations + + // AutoGenIPv6LinkLocal determines whether or not the stack attempts to + // auto-generate an IPv6 link-local address for newly enabled non-loopback + // NICs. + // + // Note, setting this to true does not mean that a link-local address is + // assigned right away, or at all. If Duplicate Address Detection is enabled, + // an address is only assigned if it successfully resolves. If it fails, no + // further attempts are made to auto-generate an IPv6 link-local adddress. + // + // The generated link-local address follows RFC 4291 Appendix A guidelines. + AutoGenIPv6LinkLocal bool + + // NDPDisp is the NDP event dispatcher that an integrator can provide to + // receive NDP related events. + NDPDisp NDPDispatcher + + // OpaqueIIDOpts hold the options for generating opaque interface + // identifiers (IIDs) as outlined by RFC 7217. + OpaqueIIDOpts OpaqueInterfaceIdentifierOptions + + // TempIIDSeed is used to seed the initial temporary interface identifier + // history value used to generate IIDs for temporary SLAAC addresses. + // + // Temporary SLAAC adresses are short-lived addresses which are unpredictable + // and random from the perspective of other nodes on the network. It is + // recommended that the seed be a random byte buffer of at least + // header.IIDSize bytes to make sure that temporary SLAAC addresses are + // sufficiently random. It should follow minimum randomness requirements for + // security as outlined by RFC 4086. + // + // Note: using a nil value, the same seed across netstack program runs, or a + // seed that is too small would reduce randomness and increase predictability, + // defeating the purpose of temporary SLAAC addresses. + TempIIDSeed []byte +} + +// NewProtocolWithOptions returns an IPv6 network protocol. +func NewProtocolWithOptions(opts Options) stack.NetworkProtocolFactory { + opts.NDPConfigs.validate() + + return func(*stack.Stack) stack.NetworkProtocol { + p := &protocol{ + fragmentation: fragmentation.NewFragmentation(header.IPv6FragmentExtHdrFragmentOffsetBytesPerUnit, fragmentation.HighFragThreshold, fragmentation.LowFragThreshold, fragmentation.DefaultReassembleTimeout), + + ndpDisp: opts.NDPDisp, + ndpConfigs: opts.NDPConfigs, + opaqueIIDOpts: opts.OpaqueIIDOpts, + tempIIDSeed: opts.TempIIDSeed, + autoGenIPv6LinkLocal: opts.AutoGenIPv6LinkLocal, + } + p.mu.eps = make(map[*endpoint]struct{}) + p.SetDefaultTTL(DefaultTTL) + return p } } + +// NewProtocol is equivalent to NewProtocolWithOptions with an empty Options. +func NewProtocol(s *stack.Stack) stack.NetworkProtocol { + return NewProtocolWithOptions(Options{})(s) +} diff --git a/pkg/tcpip/stack/ndp.go b/pkg/tcpip/network/ipv6/ndp.go index 97ca00d16..1b5c61b80 100644 --- a/pkg/tcpip/stack/ndp.go +++ b/pkg/tcpip/network/ipv6/ndp.go @@ -12,7 +12,7 @@ // See the License for the specific language governing permissions and // limitations under the License. -package stack +package ipv6 import ( "fmt" @@ -23,9 +23,27 @@ import ( "gvisor.dev/gvisor/pkg/tcpip" "gvisor.dev/gvisor/pkg/tcpip/buffer" "gvisor.dev/gvisor/pkg/tcpip/header" + "gvisor.dev/gvisor/pkg/tcpip/stack" ) const ( + // defaultRetransmitTimer is the default amount of time to wait between + // sending reachability probes. + // + // Default taken from RETRANS_TIMER of RFC 4861 section 10. + defaultRetransmitTimer = time.Second + + // minimumRetransmitTimer is the minimum amount of time to wait between + // sending reachability probes. + // + // Note, RFC 4861 does not impose a minimum Retransmit Timer, but we do here + // to make sure the messages are not sent all at once. We also come to this + // value because in the RetransmitTimer field of a Router Advertisement, a + // value of 0 means unspecified, so the smallest valid value is 1. Note, the + // unit of the RetransmitTimer field in the Router Advertisement is + // milliseconds. + minimumRetransmitTimer = time.Millisecond + // defaultDupAddrDetectTransmits is the default number of NDP Neighbor // Solicitation messages to send when doing Duplicate Address Detection // for a tentative address. @@ -34,7 +52,7 @@ const ( defaultDupAddrDetectTransmits = 1 // defaultMaxRtrSolicitations is the default number of Router - // Solicitation messages to send when a NIC becomes enabled. + // Solicitation messages to send when an IPv6 endpoint becomes enabled. // // Default = 3 (from RFC 4861 section 10). defaultMaxRtrSolicitations = 3 @@ -131,7 +149,7 @@ const ( minRegenAdvanceDuration = time.Duration(0) // maxSLAACAddrLocalRegenAttempts is the maximum number of times to attempt - // SLAAC address regenerations in response to a NIC-local conflict. + // SLAAC address regenerations in response to an IPv6 endpoint-local conflict. maxSLAACAddrLocalRegenAttempts = 10 ) @@ -163,7 +181,7 @@ var ( // This is exported as a variable (instead of a constant) so tests // can update it to a smaller value. // - // This value guarantees that a temporary address will be preferred for at + // This value guarantees that a temporary address is preferred for at // least 1hr if the SLAAC prefix is valid for at least that time. MinMaxTempAddrPreferredLifetime = defaultRegenAdvanceDuration + MaxDesyncFactor + time.Hour @@ -173,11 +191,17 @@ var ( // This is exported as a variable (instead of a constant) so tests // can update it to a smaller value. // - // This value guarantees that a temporary address will be valid for at least + // This value guarantees that a temporary address is valid for at least // 2hrs if the SLAAC prefix is valid for at least that time. MinMaxTempAddrValidLifetime = 2 * time.Hour ) +// NDPEndpoint is an endpoint that supports NDP. +type NDPEndpoint interface { + // SetNDPConfigurations sets the NDP configurations. + SetNDPConfigurations(NDPConfigurations) +} + // DHCPv6ConfigurationFromNDPRA is a configuration available via DHCPv6 that an // NDP Router Advertisement informed the Stack about. type DHCPv6ConfigurationFromNDPRA int @@ -192,7 +216,7 @@ const ( // DHCPv6ManagedAddress indicates that addresses are available via DHCPv6. // // DHCPv6ManagedAddress also implies DHCPv6OtherConfigurations because DHCPv6 - // will return all available configuration information. + // returns all available configuration information when serving addresses. DHCPv6ManagedAddress // DHCPv6OtherConfigurations indicates that other configuration information is @@ -207,19 +231,18 @@ const ( // NDPDispatcher is the interface integrators of netstack must implement to // receive and handle NDP related events. type NDPDispatcher interface { - // OnDuplicateAddressDetectionStatus will be called when the DAD process - // for an address (addr) on a NIC (with ID nicID) completes. resolved - // will be set to true if DAD completed successfully (no duplicate addr - // detected); false otherwise (addr was detected to be a duplicate on - // the link the NIC is a part of, or it was stopped for some other - // reason, such as the address being removed). If an error occured - // during DAD, err will be set and resolved must be ignored. + // OnDuplicateAddressDetectionStatus is called when the DAD process for an + // address (addr) on a NIC (with ID nicID) completes. resolved is set to true + // if DAD completed successfully (no duplicate addr detected); false otherwise + // (addr was detected to be a duplicate on the link the NIC is a part of, or + // it was stopped for some other reason, such as the address being removed). + // If an error occured during DAD, err is set and resolved must be ignored. // // This function is not permitted to block indefinitely. This function // is also not permitted to call into the stack. OnDuplicateAddressDetectionStatus(nicID tcpip.NICID, addr tcpip.Address, resolved bool, err *tcpip.Error) - // OnDefaultRouterDiscovered will be called when a new default router is + // OnDefaultRouterDiscovered is called when a new default router is // discovered. Implementations must return true if the newly discovered // router should be remembered. // @@ -227,56 +250,55 @@ type NDPDispatcher interface { // is also not permitted to call into the stack. OnDefaultRouterDiscovered(nicID tcpip.NICID, addr tcpip.Address) bool - // OnDefaultRouterInvalidated will be called when a discovered default - // router that was remembered is invalidated. + // OnDefaultRouterInvalidated is called when a discovered default router that + // was remembered is invalidated. // // This function is not permitted to block indefinitely. This function // is also not permitted to call into the stack. OnDefaultRouterInvalidated(nicID tcpip.NICID, addr tcpip.Address) - // OnOnLinkPrefixDiscovered will be called when a new on-link prefix is - // discovered. Implementations must return true if the newly discovered - // on-link prefix should be remembered. + // OnOnLinkPrefixDiscovered is called when a new on-link prefix is discovered. + // Implementations must return true if the newly discovered on-link prefix + // should be remembered. // // This function is not permitted to block indefinitely. This function // is also not permitted to call into the stack. OnOnLinkPrefixDiscovered(nicID tcpip.NICID, prefix tcpip.Subnet) bool - // OnOnLinkPrefixInvalidated will be called when a discovered on-link - // prefix that was remembered is invalidated. + // OnOnLinkPrefixInvalidated is called when a discovered on-link prefix that + // was remembered is invalidated. // // This function is not permitted to block indefinitely. This function // is also not permitted to call into the stack. OnOnLinkPrefixInvalidated(nicID tcpip.NICID, prefix tcpip.Subnet) - // OnAutoGenAddress will be called when a new prefix with its - // autonomous address-configuration flag set has been received and SLAAC - // has been performed. Implementations may prevent the stack from - // assigning the address to the NIC by returning false. + // OnAutoGenAddress is called when a new prefix with its autonomous address- + // configuration flag set is received and SLAAC was performed. Implementations + // may prevent the stack from assigning the address to the NIC by returning + // false. // // This function is not permitted to block indefinitely. It must not // call functions on the stack itself. OnAutoGenAddress(tcpip.NICID, tcpip.AddressWithPrefix) bool - // OnAutoGenAddressDeprecated will be called when an auto-generated - // address (as part of SLAAC) has been deprecated, but is still - // considered valid. Note, if an address is invalidated at the same - // time it is deprecated, the deprecation event MAY be omitted. + // OnAutoGenAddressDeprecated is called when an auto-generated address (SLAAC) + // is deprecated, but is still considered valid. Note, if an address is + // invalidated at the same ime it is deprecated, the deprecation event may not + // be received. // // This function is not permitted to block indefinitely. It must not // call functions on the stack itself. OnAutoGenAddressDeprecated(tcpip.NICID, tcpip.AddressWithPrefix) - // OnAutoGenAddressInvalidated will be called when an auto-generated - // address (as part of SLAAC) has been invalidated. + // OnAutoGenAddressInvalidated is called when an auto-generated address + // (SLAAC) is invalidated. // // This function is not permitted to block indefinitely. It must not // call functions on the stack itself. OnAutoGenAddressInvalidated(tcpip.NICID, tcpip.AddressWithPrefix) - // OnRecursiveDNSServerOption will be called when an NDP option with - // recursive DNS servers has been received. Note, addrs may contain - // link-local addresses. + // OnRecursiveDNSServerOption is called when the stack learns of DNS servers + // through NDP. Note, the addresses may contain link-local addresses. // // It is up to the caller to use the DNS Servers only for their valid // lifetime. OnRecursiveDNSServerOption may be called for new or @@ -288,8 +310,8 @@ type NDPDispatcher interface { // call functions on the stack itself. OnRecursiveDNSServerOption(nicID tcpip.NICID, addrs []tcpip.Address, lifetime time.Duration) - // OnDNSSearchListOption will be called when an NDP option with a DNS - // search list has been received. + // OnDNSSearchListOption is called when the stack learns of DNS search lists + // through NDP. // // It is up to the caller to use the domain names in the search list // for only their valid lifetime. OnDNSSearchListOption may be called @@ -298,8 +320,8 @@ type NDPDispatcher interface { // be increased, decreased or completely invalidated when lifetime = 0. OnDNSSearchListOption(nicID tcpip.NICID, domainNames []string, lifetime time.Duration) - // OnDHCPv6Configuration will be called with an updated configuration that is - // available via DHCPv6 for a specified NIC. + // OnDHCPv6Configuration is called with an updated configuration that is + // available via DHCPv6 for the passed NIC. // // This function is not permitted to block indefinitely. It must not // call functions on the stack itself. @@ -320,7 +342,7 @@ type NDPConfigurations struct { // Must be greater than or equal to 1ms. RetransmitTimer time.Duration - // The number of Router Solicitation messages to send when the NIC + // The number of Router Solicitation messages to send when the IPv6 endpoint // becomes enabled. MaxRtrSolicitations uint8 @@ -335,24 +357,22 @@ type NDPConfigurations struct { // Must be greater than or equal to 0s. MaxRtrSolicitationDelay time.Duration - // HandleRAs determines whether or not Router Advertisements will be - // processed. + // HandleRAs determines whether or not Router Advertisements are processed. HandleRAs bool - // DiscoverDefaultRouters determines whether or not default routers will - // be discovered from Router Advertisements. This configuration is - // ignored if HandleRAs is false. + // DiscoverDefaultRouters determines whether or not default routers are + // discovered from Router Advertisements, as per RFC 4861 section 6. This + // configuration is ignored if HandleRAs is false. DiscoverDefaultRouters bool - // DiscoverOnLinkPrefixes determines whether or not on-link prefixes - // will be discovered from Router Advertisements' Prefix Information - // option. This configuration is ignored if HandleRAs is false. + // DiscoverOnLinkPrefixes determines whether or not on-link prefixes are + // discovered from Router Advertisements' Prefix Information option, as per + // RFC 4861 section 6. This configuration is ignored if HandleRAs is false. DiscoverOnLinkPrefixes bool - // AutoGenGlobalAddresses determines whether or not global IPv6 - // addresses will be generated for a NIC in response to receiving a new - // Prefix Information option with its Autonomous Address - // AutoConfiguration flag set, as a host, as per RFC 4862 (SLAAC). + // AutoGenGlobalAddresses determines whether or not an IPv6 endpoint performs + // SLAAC to auto-generate global SLAAC addresses in response to Prefix + // Information options, as per RFC 4862. // // Note, if an address was already generated for some unique prefix, as // part of SLAAC, this option does not affect whether or not the @@ -366,12 +386,12 @@ type NDPConfigurations struct { // // If the method used to generate the address does not support creating // alternative addresses (e.g. IIDs based on the modified EUI64 of a NIC's - // MAC address), then no attempt will be made to resolve the conflict. + // MAC address), then no attempt is made to resolve the conflict. AutoGenAddressConflictRetries uint8 // AutoGenTempGlobalAddresses determines whether or not temporary SLAAC - // addresses will be generated for a NIC as part of SLAAC privacy extensions, - // RFC 4941. + // addresses are generated for an IPv6 endpoint as part of SLAAC privacy + // extensions, as per RFC 4941. // // Ignored if AutoGenGlobalAddresses is false. AutoGenTempGlobalAddresses bool @@ -410,7 +430,7 @@ func DefaultNDPConfigurations() NDPConfigurations { } // validate modifies an NDPConfigurations with valid values. If invalid values -// are present in c, the corresponding default values will be used instead. +// are present in c, the corresponding default values are used instead. func (c *NDPConfigurations) validate() { if c.RetransmitTimer < minimumRetransmitTimer { c.RetransmitTimer = defaultRetransmitTimer @@ -439,8 +459,8 @@ func (c *NDPConfigurations) validate() { // ndpState is the per-interface NDP state. type ndpState struct { - // The NIC this ndpState is for. - nic *NIC + // The IPv6 endpoint this ndpState is for. + ep *endpoint // configs is the per-interface NDP configurations. configs NDPConfigurations @@ -458,8 +478,8 @@ type ndpState struct { // Used to let the Router Solicitation timer know that it has been stopped. // // Must only be read from or written to while protected by the lock of - // the NIC this ndpState is associated with. MUST be set when the timer is - // set. + // the IPv6 endpoint this ndpState is associated with. MUST be set when the + // timer is set. done *bool } @@ -492,7 +512,7 @@ type dadState struct { // Used to let the DAD timer know that it has been stopped. // // Must only be read from or written to while protected by the lock of - // the NIC this dadState is associated with. + // the IPv6 endpoint this dadState is associated with. done *bool } @@ -537,7 +557,7 @@ type tempSLAACAddrState struct { // The address's endpoint. // // Must not be nil. - ref *referencedNetworkEndpoint + addressEndpoint stack.AddressEndpoint // Has a new temporary SLAAC address already been regenerated? regenerated bool @@ -567,10 +587,10 @@ type slaacPrefixState struct { // // May only be nil when the address is being (re-)generated. Otherwise, // must not be nil as all SLAAC prefixes must have a stable address. - ref *referencedNetworkEndpoint + addressEndpoint stack.AddressEndpoint - // The number of times an address has been generated locally where the NIC - // already had the generated address. + // The number of times an address has been generated locally where the IPv6 + // endpoint already had the generated address. localGenerationFailures uint8 } @@ -578,11 +598,12 @@ type slaacPrefixState struct { tempAddrs map[tcpip.Address]tempSLAACAddrState // The next two fields are used by both stable and temporary addresses - // generated for a SLAAC prefix. This is safe as only 1 address will be - // in the generation and DAD process at any time. That is, no two addresses - // will be generated at the same time for a given SLAAC prefix. + // generated for a SLAAC prefix. This is safe as only 1 address is in the + // generation and DAD process at any time. That is, no two addresses are + // generated at the same time for a given SLAAC prefix. - // The number of times an address has been generated and added to the NIC. + // The number of times an address has been generated and added to the IPv6 + // endpoint. // // Addresses may be regenerated in reseponse to a DAD conflicts. generationAttempts uint8 @@ -597,16 +618,16 @@ type slaacPrefixState struct { // This function must only be called by IPv6 addresses that are currently // tentative. // -// The NIC that ndp belongs to MUST be locked. -func (ndp *ndpState) startDuplicateAddressDetection(addr tcpip.Address, ref *referencedNetworkEndpoint) *tcpip.Error { +// The IPv6 endpoint that ndp belongs to MUST be locked. +func (ndp *ndpState) startDuplicateAddressDetection(addr tcpip.Address, addressEndpoint stack.AddressEndpoint) *tcpip.Error { // addr must be a valid unicast IPv6 address. if !header.IsV6UnicastAddress(addr) { return tcpip.ErrAddressFamilyNotSupported } - if ref.getKind() != permanentTentative { + if addressEndpoint.GetKind() != stack.PermanentTentative { // The endpoint should be marked as tentative since we are starting DAD. - panic(fmt.Sprintf("ndpdad: addr %s is not tentative on NIC(%d)", addr, ndp.nic.ID())) + panic(fmt.Sprintf("ndpdad: addr %s is not tentative on NIC(%d)", addr, ndp.ep.NICID())) } // Should not attempt to perform DAD on an address that is currently in the @@ -617,18 +638,18 @@ func (ndp *ndpState) startDuplicateAddressDetection(addr tcpip.Address, ref *ref // existed, we would get an error since we attempted to add a duplicate // address, or its reference count would have been increased without doing // the work that would have been done for an address that was brand new. - // See NIC.addAddressLocked. - panic(fmt.Sprintf("ndpdad: already performing DAD for addr %s on NIC(%d)", addr, ndp.nic.ID())) + // See endpoint.addAddressLocked. + panic(fmt.Sprintf("ndpdad: already performing DAD for addr %s on NIC(%d)", addr, ndp.ep.NICID())) } remaining := ndp.configs.DupAddrDetectTransmits if remaining == 0 { - ref.setKind(permanent) + addressEndpoint.SetKind(stack.Permanent) // Consider DAD to have resolved even if no DAD messages were actually // transmitted. - if ndpDisp := ndp.nic.stack.ndpDisp; ndpDisp != nil { - ndpDisp.OnDuplicateAddressDetectionStatus(ndp.nic.ID(), addr, true, nil) + if ndpDisp := ndp.ep.protocol.ndpDisp; ndpDisp != nil { + ndpDisp.OnDuplicateAddressDetectionStatus(ndp.ep.NICID(), addr, true, nil) } return nil @@ -637,25 +658,25 @@ func (ndp *ndpState) startDuplicateAddressDetection(addr tcpip.Address, ref *ref var done bool var timer tcpip.Timer // We initially start a timer to fire immediately because some of the DAD work - // cannot be done while holding the NIC's lock. This is effectively the same - // as starting a goroutine but we use a timer that fires immediately so we can - // reset it for the next DAD iteration. - timer = ndp.nic.stack.Clock().AfterFunc(0, func() { - ndp.nic.mu.Lock() - defer ndp.nic.mu.Unlock() + // cannot be done while holding the IPv6 endpoint's lock. This is effectively + // the same as starting a goroutine but we use a timer that fires immediately + // so we can reset it for the next DAD iteration. + timer = ndp.ep.stack.Clock().AfterFunc(0, func() { + ndp.ep.mu.Lock() + defer ndp.ep.mu.Unlock() if done { // If we reach this point, it means that the DAD timer fired after - // another goroutine already obtained the NIC lock and stopped DAD - // before this function obtained the NIC lock. Simply return here and do - // nothing further. + // another goroutine already obtained the IPv6 endpoint lock and stopped + // DAD before this function obtained the NIC lock. Simply return here and + // do nothing further. return } - if ref.getKind() != permanentTentative { + if addressEndpoint.GetKind() != stack.PermanentTentative { // The endpoint should still be marked as tentative since we are still // performing DAD on it. - panic(fmt.Sprintf("ndpdad: addr %s is no longer tentative on NIC(%d)", addr, ndp.nic.ID())) + panic(fmt.Sprintf("ndpdad: addr %s is no longer tentative on NIC(%d)", addr, ndp.ep.NICID())) } dadDone := remaining == 0 @@ -663,33 +684,34 @@ func (ndp *ndpState) startDuplicateAddressDetection(addr tcpip.Address, ref *ref var err *tcpip.Error if !dadDone { // Use the unspecified address as the source address when performing DAD. - ref := ndp.nic.getRefOrCreateTempLocked(header.IPv6ProtocolNumber, header.IPv6Any, NeverPrimaryEndpoint) + addressEndpoint := ndp.ep.acquireAddressOrCreateTempLocked(header.IPv6Any, true /* createTemp */, stack.NeverPrimaryEndpoint) // Do not hold the lock when sending packets which may be a long running // task or may block link address resolution. We know this is safe // because immediately after obtaining the lock again, we check if DAD - // has been stopped before doing any work with the NIC. Note, DAD would be - // stopped if the NIC was disabled or removed, or if the address was - // removed. - ndp.nic.mu.Unlock() - err = ndp.sendDADPacket(addr, ref) - ndp.nic.mu.Lock() + // has been stopped before doing any work with the IPv6 endpoint. Note, + // DAD would be stopped if the IPv6 endpoint was disabled or closed, or if + // the address was removed. + ndp.ep.mu.Unlock() + err = ndp.sendDADPacket(addr, addressEndpoint) + ndp.ep.mu.Lock() + addressEndpoint.DecRef() } if done { // If we reach this point, it means that DAD was stopped after we released - // the NIC's read lock and before we obtained the write lock. + // the IPv6 endpoint's read lock and before we obtained the write lock. return } if dadDone { // DAD has resolved. - ref.setKind(permanent) + addressEndpoint.SetKind(stack.Permanent) } else if err == nil { // DAD is not done and we had no errors when sending the last NDP NS, // schedule the next DAD timer. remaining-- - timer.Reset(ndp.nic.stack.ndpConfigs.RetransmitTimer) + timer.Reset(ndp.configs.RetransmitTimer) return } @@ -698,16 +720,16 @@ func (ndp *ndpState) startDuplicateAddressDetection(addr tcpip.Address, ref *ref // integrator know DAD has completed. delete(ndp.dad, addr) - if ndpDisp := ndp.nic.stack.ndpDisp; ndpDisp != nil { - ndpDisp.OnDuplicateAddressDetectionStatus(ndp.nic.ID(), addr, dadDone, err) + if ndpDisp := ndp.ep.protocol.ndpDisp; ndpDisp != nil { + ndpDisp.OnDuplicateAddressDetectionStatus(ndp.ep.NICID(), addr, dadDone, err) } // If DAD resolved for a stable SLAAC address, attempt generation of a // temporary SLAAC address. - if dadDone && ref.configType == slaac { + if dadDone && addressEndpoint.ConfigType() == stack.AddressConfigSlaac { // Reset the generation attempts counter as we are starting the generation // of a new address for the SLAAC prefix. - ndp.regenerateTempSLAACAddr(ref.addrWithPrefix().Subnet(), true /* resetGenAttempts */) + ndp.regenerateTempSLAACAddr(addressEndpoint.AddressWithPrefix().Subnet(), true /* resetGenAttempts */) } }) @@ -722,28 +744,31 @@ func (ndp *ndpState) startDuplicateAddressDetection(addr tcpip.Address, ref *ref // sendDADPacket sends a NS message to see if any nodes on ndp's NIC's link owns // addr. // -// addr must be a tentative IPv6 address on ndp's NIC. +// addr must be a tentative IPv6 address on ndp's IPv6 endpoint. // -// The NIC ndp belongs to MUST NOT be locked. -func (ndp *ndpState) sendDADPacket(addr tcpip.Address, ref *referencedNetworkEndpoint) *tcpip.Error { +// The IPv6 endpoint that ndp belongs to MUST NOT be locked. +func (ndp *ndpState) sendDADPacket(addr tcpip.Address, addressEndpoint stack.AddressEndpoint) *tcpip.Error { snmc := header.SolicitedNodeAddr(addr) - r := makeRoute(header.IPv6ProtocolNumber, ref.address(), snmc, ndp.nic.linkEP.LinkAddress(), ref, false, false) + r, err := ndp.ep.stack.FindRoute(ndp.ep.NICID(), header.IPv6Any, snmc, ProtocolNumber, false /* multicastLoop */) + if err != nil { + return err + } defer r.Release() // Route should resolve immediately since snmc is a multicast address so a // remote link address can be calculated without a resolution process. if c, err := r.Resolve(nil); err != nil { // Do not consider the NIC being unknown or disabled as a fatal error. - // Since this method is required to be called when the NIC is not locked, - // the NIC could have been disabled or removed by another goroutine. + // Since this method is required to be called when the IPv6 endpoint is not + // locked, the NIC could have been disabled or removed by another goroutine. if err == tcpip.ErrUnknownNICID || err != tcpip.ErrInvalidEndpointState { return err } - panic(fmt.Sprintf("ndp: error when resolving route to send NDP NS for DAD (%s -> %s on NIC(%d)): %s", header.IPv6Any, snmc, ndp.nic.ID(), err)) + panic(fmt.Sprintf("ndp: error when resolving route to send NDP NS for DAD (%s -> %s on NIC(%d)): %s", header.IPv6Any, snmc, ndp.ep.NICID(), err)) } else if c != nil { - panic(fmt.Sprintf("ndp: route resolution not immediate for route to send NDP NS for DAD (%s -> %s on NIC(%d))", header.IPv6Any, snmc, ndp.nic.ID())) + panic(fmt.Sprintf("ndp: route resolution not immediate for route to send NDP NS for DAD (%s -> %s on NIC(%d))", header.IPv6Any, snmc, ndp.ep.NICID())) } icmpData := header.ICMPv6(buffer.NewView(header.ICMPv6NeighborSolicitMinimumSize)) @@ -752,17 +777,16 @@ func (ndp *ndpState) sendDADPacket(addr tcpip.Address, ref *referencedNetworkEnd ns.SetTargetAddress(addr) icmpData.SetChecksum(header.ICMPv6Checksum(icmpData, r.LocalAddress, r.RemoteAddress, buffer.VectorisedView{})) - pkt := NewPacketBuffer(PacketBufferOptions{ + pkt := stack.NewPacketBuffer(stack.PacketBufferOptions{ ReserveHeaderBytes: int(r.MaxHeaderLength()), Data: buffer.View(icmpData).ToVectorisedView(), }) sent := r.Stats().ICMP.V6PacketsSent if err := r.WritePacket(nil, - NetworkHeaderParams{ + stack.NetworkHeaderParams{ Protocol: header.ICMPv6ProtocolNumber, TTL: header.NDPHopLimit, - TOS: DefaultTOS, }, pkt, ); err != nil { sent.Dropped.Increment() @@ -778,11 +802,9 @@ func (ndp *ndpState) sendDADPacket(addr tcpip.Address, ref *referencedNetworkEnd // such a state forever, unless some other external event resolves the DAD // process (receiving an NA from the true owner of addr, or an NS for addr // (implying another node is attempting to use addr)). It is up to the caller -// of this function to handle such a scenario. Normally, addr will be removed -// from n right after this function returns or the address successfully -// resolved. +// of this function to handle such a scenario. // -// The NIC that ndp belongs to MUST be locked. +// The IPv6 endpoint that ndp belongs to MUST be locked. func (ndp *ndpState) stopDuplicateAddressDetection(addr tcpip.Address) { dad, ok := ndp.dad[addr] if !ok { @@ -801,30 +823,30 @@ func (ndp *ndpState) stopDuplicateAddressDetection(addr tcpip.Address) { delete(ndp.dad, addr) // Let the integrator know DAD did not resolve. - if ndpDisp := ndp.nic.stack.ndpDisp; ndpDisp != nil { - ndpDisp.OnDuplicateAddressDetectionStatus(ndp.nic.ID(), addr, false, nil) + if ndpDisp := ndp.ep.protocol.ndpDisp; ndpDisp != nil { + ndpDisp.OnDuplicateAddressDetectionStatus(ndp.ep.NICID(), addr, false, nil) } } // handleRA handles a Router Advertisement message that arrived on the NIC // this ndp is for. Does nothing if the NIC is configured to not handle RAs. // -// The NIC that ndp belongs to MUST be locked. +// The IPv6 endpoint that ndp belongs to MUST be locked. func (ndp *ndpState) handleRA(ip tcpip.Address, ra header.NDPRouterAdvert) { - // Is the NIC configured to handle RAs at all? + // Is the IPv6 endpoint configured to handle RAs at all? // // Currently, the stack does not determine router interface status on a - // per-interface basis; it is a stack-wide configuration, so we check - // stack's forwarding flag to determine if the NIC is a routing - // interface. - if !ndp.configs.HandleRAs || ndp.nic.stack.Forwarding(header.IPv6ProtocolNumber) { + // per-interface basis; it is a protocol-wide configuration, so we check the + // protocol's forwarding flag to determine if the IPv6 endpoint is forwarding + // packets. + if !ndp.configs.HandleRAs || ndp.ep.protocol.Forwarding() { return } // Only worry about the DHCPv6 configuration if we have an NDPDispatcher as we // only inform the dispatcher on configuration changes. We do nothing else // with the information. - if ndpDisp := ndp.nic.stack.ndpDisp; ndpDisp != nil { + if ndpDisp := ndp.ep.protocol.ndpDisp; ndpDisp != nil { var configuration DHCPv6ConfigurationFromNDPRA switch { case ra.ManagedAddrConfFlag(): @@ -839,11 +861,11 @@ func (ndp *ndpState) handleRA(ip tcpip.Address, ra header.NDPRouterAdvert) { if ndp.dhcpv6Configuration != configuration { ndp.dhcpv6Configuration = configuration - ndpDisp.OnDHCPv6Configuration(ndp.nic.ID(), configuration) + ndpDisp.OnDHCPv6Configuration(ndp.ep.NICID(), configuration) } } - // Is the NIC configured to discover default routers? + // Is the IPv6 endpoint configured to discover default routers? if ndp.configs.DiscoverDefaultRouters { rtr, ok := ndp.defaultRouters[ip] rl := ra.RouterLifetime() @@ -881,20 +903,20 @@ func (ndp *ndpState) handleRA(ip tcpip.Address, ra header.NDPRouterAdvert) { for opt, done, _ := it.Next(); !done; opt, done, _ = it.Next() { switch opt := opt.(type) { case header.NDPRecursiveDNSServer: - if ndp.nic.stack.ndpDisp == nil { + if ndp.ep.protocol.ndpDisp == nil { continue } addrs, _ := opt.Addresses() - ndp.nic.stack.ndpDisp.OnRecursiveDNSServerOption(ndp.nic.ID(), addrs, opt.Lifetime()) + ndp.ep.protocol.ndpDisp.OnRecursiveDNSServerOption(ndp.ep.NICID(), addrs, opt.Lifetime()) case header.NDPDNSSearchList: - if ndp.nic.stack.ndpDisp == nil { + if ndp.ep.protocol.ndpDisp == nil { continue } domainNames, _ := opt.DomainNames() - ndp.nic.stack.ndpDisp.OnDNSSearchListOption(ndp.nic.ID(), domainNames, opt.Lifetime()) + ndp.ep.protocol.ndpDisp.OnDNSSearchListOption(ndp.ep.NICID(), domainNames, opt.Lifetime()) case header.NDPPrefixInformation: prefix := opt.Subnet() @@ -928,7 +950,7 @@ func (ndp *ndpState) handleRA(ip tcpip.Address, ra header.NDPRouterAdvert) { // invalidateDefaultRouter invalidates a discovered default router. // -// The NIC that ndp belongs to MUST be locked. +// The IPv6 endpoint that ndp belongs to MUST be locked. func (ndp *ndpState) invalidateDefaultRouter(ip tcpip.Address) { rtr, ok := ndp.defaultRouters[ip] @@ -942,32 +964,32 @@ func (ndp *ndpState) invalidateDefaultRouter(ip tcpip.Address) { delete(ndp.defaultRouters, ip) // Let the integrator know a discovered default router is invalidated. - if ndpDisp := ndp.nic.stack.ndpDisp; ndpDisp != nil { - ndpDisp.OnDefaultRouterInvalidated(ndp.nic.ID(), ip) + if ndpDisp := ndp.ep.protocol.ndpDisp; ndpDisp != nil { + ndpDisp.OnDefaultRouterInvalidated(ndp.ep.NICID(), ip) } } // rememberDefaultRouter remembers a newly discovered default router with IPv6 // link-local address ip with lifetime rl. // -// The router identified by ip MUST NOT already be known by the NIC. +// The router identified by ip MUST NOT already be known by the IPv6 endpoint. // -// The NIC that ndp belongs to MUST be locked. +// The IPv6 endpoint that ndp belongs to MUST be locked. func (ndp *ndpState) rememberDefaultRouter(ip tcpip.Address, rl time.Duration) { - ndpDisp := ndp.nic.stack.ndpDisp + ndpDisp := ndp.ep.protocol.ndpDisp if ndpDisp == nil { return } // Inform the integrator when we discovered a default router. - if !ndpDisp.OnDefaultRouterDiscovered(ndp.nic.ID(), ip) { + if !ndpDisp.OnDefaultRouterDiscovered(ndp.ep.NICID(), ip) { // Informed by the integrator to not remember the router, do // nothing further. return } state := defaultRouterState{ - invalidationJob: ndp.nic.stack.newJob(&ndp.nic.mu, func() { + invalidationJob: ndp.ep.stack.NewJob(&ndp.ep.mu, func() { ndp.invalidateDefaultRouter(ip) }), } @@ -982,22 +1004,22 @@ func (ndp *ndpState) rememberDefaultRouter(ip tcpip.Address, rl time.Duration) { // // The prefix identified by prefix MUST NOT already be known. // -// The NIC that ndp belongs to MUST be locked. +// The IPv6 endpoint that ndp belongs to MUST be locked. func (ndp *ndpState) rememberOnLinkPrefix(prefix tcpip.Subnet, l time.Duration) { - ndpDisp := ndp.nic.stack.ndpDisp + ndpDisp := ndp.ep.protocol.ndpDisp if ndpDisp == nil { return } // Inform the integrator when we discovered an on-link prefix. - if !ndpDisp.OnOnLinkPrefixDiscovered(ndp.nic.ID(), prefix) { + if !ndpDisp.OnOnLinkPrefixDiscovered(ndp.ep.NICID(), prefix) { // Informed by the integrator to not remember the prefix, do // nothing further. return } state := onLinkPrefixState{ - invalidationJob: ndp.nic.stack.newJob(&ndp.nic.mu, func() { + invalidationJob: ndp.ep.stack.NewJob(&ndp.ep.mu, func() { ndp.invalidateOnLinkPrefix(prefix) }), } @@ -1011,7 +1033,7 @@ func (ndp *ndpState) rememberOnLinkPrefix(prefix tcpip.Subnet, l time.Duration) // invalidateOnLinkPrefix invalidates a discovered on-link prefix. // -// The NIC that ndp belongs to MUST be locked. +// The IPv6 endpoint that ndp belongs to MUST be locked. func (ndp *ndpState) invalidateOnLinkPrefix(prefix tcpip.Subnet) { s, ok := ndp.onLinkPrefixes[prefix] @@ -1025,8 +1047,8 @@ func (ndp *ndpState) invalidateOnLinkPrefix(prefix tcpip.Subnet) { delete(ndp.onLinkPrefixes, prefix) // Let the integrator know a discovered on-link prefix is invalidated. - if ndpDisp := ndp.nic.stack.ndpDisp; ndpDisp != nil { - ndpDisp.OnOnLinkPrefixInvalidated(ndp.nic.ID(), prefix) + if ndpDisp := ndp.ep.protocol.ndpDisp; ndpDisp != nil { + ndpDisp.OnOnLinkPrefixInvalidated(ndp.ep.NICID(), prefix) } } @@ -1036,7 +1058,7 @@ func (ndp *ndpState) invalidateOnLinkPrefix(prefix tcpip.Subnet) { // handleOnLinkPrefixInformation assumes that the prefix this pi is for is // not the link-local prefix and the on-link flag is set. // -// The NIC that ndp belongs to MUST be locked. +// The IPv6 endpoint that ndp belongs to MUST be locked. func (ndp *ndpState) handleOnLinkPrefixInformation(pi header.NDPPrefixInformation) { prefix := pi.Subnet() prefixState, ok := ndp.onLinkPrefixes[prefix] @@ -1089,7 +1111,7 @@ func (ndp *ndpState) handleOnLinkPrefixInformation(pi header.NDPPrefixInformatio // handleAutonomousPrefixInformation assumes that the prefix this pi is for is // not the link-local prefix and the autonomous flag is set. // -// The NIC that ndp belongs to MUST be locked. +// The IPv6 endpoint that ndp belongs to MUST be locked. func (ndp *ndpState) handleAutonomousPrefixInformation(pi header.NDPPrefixInformation) { vl := pi.ValidLifetime() pl := pi.PreferredLifetime() @@ -1125,7 +1147,7 @@ func (ndp *ndpState) handleAutonomousPrefixInformation(pi header.NDPPrefixInform // // pl is the new preferred lifetime. vl is the new valid lifetime. // -// The NIC that ndp belongs to MUST be locked. +// The IPv6 endpoint that ndp belongs to MUST be locked. func (ndp *ndpState) doSLAAC(prefix tcpip.Subnet, pl, vl time.Duration) { // If we do not already have an address for this prefix and the valid // lifetime is 0, no need to do anything further, as per RFC 4862 @@ -1142,15 +1164,15 @@ func (ndp *ndpState) doSLAAC(prefix tcpip.Subnet, pl, vl time.Duration) { } state := slaacPrefixState{ - deprecationJob: ndp.nic.stack.newJob(&ndp.nic.mu, func() { + deprecationJob: ndp.ep.stack.NewJob(&ndp.ep.mu, func() { state, ok := ndp.slaacPrefixes[prefix] if !ok { panic(fmt.Sprintf("ndp: must have a slaacPrefixes entry for the deprecated SLAAC prefix %s", prefix)) } - ndp.deprecateSLAACAddress(state.stableAddr.ref) + ndp.deprecateSLAACAddress(state.stableAddr.addressEndpoint) }), - invalidationJob: ndp.nic.stack.newJob(&ndp.nic.mu, func() { + invalidationJob: ndp.ep.stack.NewJob(&ndp.ep.mu, func() { state, ok := ndp.slaacPrefixes[prefix] if !ok { panic(fmt.Sprintf("ndp: must have a slaacPrefixes entry for the invalidated SLAAC prefix %s", prefix)) @@ -1189,7 +1211,7 @@ func (ndp *ndpState) doSLAAC(prefix tcpip.Subnet, pl, vl time.Duration) { } // If the address is assigned (DAD resolved), generate a temporary address. - if state.stableAddr.ref.getKind() == permanent { + if state.stableAddr.addressEndpoint.GetKind() == stack.Permanent { // Reset the generation attempts counter as we are starting the generation // of a new address for the SLAAC prefix. ndp.generateTempSLAACAddr(prefix, &state, true /* resetGenAttempts */) @@ -1198,32 +1220,27 @@ func (ndp *ndpState) doSLAAC(prefix tcpip.Subnet, pl, vl time.Duration) { ndp.slaacPrefixes[prefix] = state } -// addSLAACAddr adds a SLAAC address to the NIC. +// addAndAcquireSLAACAddr adds a SLAAC address to the IPv6 endpoint. // -// The NIC that ndp belongs to MUST be locked. -func (ndp *ndpState) addSLAACAddr(addr tcpip.AddressWithPrefix, configType networkEndpointConfigType, deprecated bool) *referencedNetworkEndpoint { +// The IPv6 endpoint that ndp belongs to MUST be locked. +func (ndp *ndpState) addAndAcquireSLAACAddr(addr tcpip.AddressWithPrefix, configType stack.AddressConfigType, deprecated bool) stack.AddressEndpoint { // Inform the integrator that we have a new SLAAC address. - ndpDisp := ndp.nic.stack.ndpDisp + ndpDisp := ndp.ep.protocol.ndpDisp if ndpDisp == nil { return nil } - if !ndpDisp.OnAutoGenAddress(ndp.nic.ID(), addr) { + if !ndpDisp.OnAutoGenAddress(ndp.ep.NICID(), addr) { // Informed by the integrator not to add the address. return nil } - protocolAddr := tcpip.ProtocolAddress{ - Protocol: header.IPv6ProtocolNumber, - AddressWithPrefix: addr, - } - - ref, err := ndp.nic.addAddressLocked(protocolAddr, FirstPrimaryEndpoint, permanent, configType, deprecated) + addressEndpoint, err := ndp.ep.addAndAcquirePermanentAddressLocked(addr, stack.FirstPrimaryEndpoint, configType, deprecated) if err != nil { - panic(fmt.Sprintf("ndp: error when adding SLAAC address %+v: %s", protocolAddr, err)) + panic(fmt.Sprintf("ndp: error when adding SLAAC address %+v: %s", addr, err)) } - return ref + return addressEndpoint } // generateSLAACAddr generates a SLAAC address for prefix. @@ -1232,10 +1249,10 @@ func (ndp *ndpState) addSLAACAddr(addr tcpip.AddressWithPrefix, configType netwo // // Panics if the prefix is not a SLAAC prefix or it already has an address. // -// The NIC that ndp belongs to MUST be locked. +// The IPv6 endpoint that ndp belongs to MUST be locked. func (ndp *ndpState) generateSLAACAddr(prefix tcpip.Subnet, state *slaacPrefixState) bool { - if r := state.stableAddr.ref; r != nil { - panic(fmt.Sprintf("ndp: SLAAC prefix %s already has a permenant address %s", prefix, r.addrWithPrefix())) + if addressEndpoint := state.stableAddr.addressEndpoint; addressEndpoint != nil { + panic(fmt.Sprintf("ndp: SLAAC prefix %s already has a permenant address %s", prefix, addressEndpoint.AddressWithPrefix())) } // If we have already reached the maximum address generation attempts for the @@ -1255,11 +1272,11 @@ func (ndp *ndpState) generateSLAACAddr(prefix tcpip.Subnet, state *slaacPrefixSt } dadCounter := state.generationAttempts + state.stableAddr.localGenerationFailures - if oIID := ndp.nic.stack.opaqueIIDOpts; oIID.NICNameFromID != nil { + if oIID := ndp.ep.protocol.opaqueIIDOpts; oIID.NICNameFromID != nil { addrBytes = header.AppendOpaqueInterfaceIdentifier( addrBytes[:header.IIDOffsetInIPv6Address], prefix, - oIID.NICNameFromID(ndp.nic.ID(), ndp.nic.name), + oIID.NICNameFromID(ndp.ep.NICID(), ndp.ep.nic.Name()), dadCounter, oIID.SecretKey, ) @@ -1272,7 +1289,7 @@ func (ndp *ndpState) generateSLAACAddr(prefix tcpip.Subnet, state *slaacPrefixSt // // TODO(b/141011931): Validate a LinkEndpoint's link address (provided by // LinkEndpoint.LinkAddress) before reaching this point. - linkAddr := ndp.nic.linkEP.LinkAddress() + linkAddr := ndp.ep.linkEP.LinkAddress() if !header.IsValidUnicastEthernetAddress(linkAddr) { return false } @@ -1291,15 +1308,15 @@ func (ndp *ndpState) generateSLAACAddr(prefix tcpip.Subnet, state *slaacPrefixSt PrefixLen: validPrefixLenForAutoGen, } - if !ndp.nic.hasPermanentAddrLocked(generatedAddr.Address) { + if !ndp.ep.hasPermanentAddressRLocked(generatedAddr.Address) { break } state.stableAddr.localGenerationFailures++ } - if ref := ndp.addSLAACAddr(generatedAddr, slaac, time.Since(state.preferredUntil) >= 0 /* deprecated */); ref != nil { - state.stableAddr.ref = ref + if addressEndpoint := ndp.addAndAcquireSLAACAddr(generatedAddr, stack.AddressConfigSlaac, time.Since(state.preferredUntil) >= 0 /* deprecated */); addressEndpoint != nil { + state.stableAddr.addressEndpoint = addressEndpoint state.generationAttempts++ return true } @@ -1309,10 +1326,9 @@ func (ndp *ndpState) generateSLAACAddr(prefix tcpip.Subnet, state *slaacPrefixSt // regenerateSLAACAddr regenerates an address for a SLAAC prefix. // -// If generating a new address for the prefix fails, the prefix will be -// invalidated. +// If generating a new address for the prefix fails, the prefix is invalidated. // -// The NIC that ndp belongs to MUST be locked. +// The IPv6 endpoint that ndp belongs to MUST be locked. func (ndp *ndpState) regenerateSLAACAddr(prefix tcpip.Subnet) { state, ok := ndp.slaacPrefixes[prefix] if !ok { @@ -1332,7 +1348,7 @@ func (ndp *ndpState) regenerateSLAACAddr(prefix tcpip.Subnet) { // generateTempSLAACAddr generates a new temporary SLAAC address. // -// If resetGenAttempts is true, the prefix's generation counter will be reset. +// If resetGenAttempts is true, the prefix's generation counter is reset. // // Returns true if a new address was generated. func (ndp *ndpState) generateTempSLAACAddr(prefix tcpip.Subnet, prefixState *slaacPrefixState, resetGenAttempts bool) bool { @@ -1353,7 +1369,7 @@ func (ndp *ndpState) generateTempSLAACAddr(prefix tcpip.Subnet, prefixState *sla return false } - stableAddr := prefixState.stableAddr.ref.address() + stableAddr := prefixState.stableAddr.addressEndpoint.AddressWithPrefix().Address now := time.Now() // As per RFC 4941 section 3.3 step 4, the valid lifetime of a temporary @@ -1392,7 +1408,8 @@ func (ndp *ndpState) generateTempSLAACAddr(prefix tcpip.Subnet, prefixState *sla return false } - // Attempt to generate a new address that is not already assigned to the NIC. + // Attempt to generate a new address that is not already assigned to the IPv6 + // endpoint. var generatedAddr tcpip.AddressWithPrefix for i := 0; ; i++ { // If we were unable to generate an address after the maximum SLAAC address @@ -1402,7 +1419,7 @@ func (ndp *ndpState) generateTempSLAACAddr(prefix tcpip.Subnet, prefixState *sla } generatedAddr = header.GenerateTempIPv6SLAACAddr(ndp.temporaryIIDHistory[:], stableAddr) - if !ndp.nic.hasPermanentAddrLocked(generatedAddr.Address) { + if !ndp.ep.hasPermanentAddressRLocked(generatedAddr.Address) { break } } @@ -1410,13 +1427,13 @@ func (ndp *ndpState) generateTempSLAACAddr(prefix tcpip.Subnet, prefixState *sla // As per RFC RFC 4941 section 3.3 step 5, we MUST NOT create a temporary // address with a zero preferred lifetime. The checks above ensure this // so we know the address is not deprecated. - ref := ndp.addSLAACAddr(generatedAddr, slaacTemp, false /* deprecated */) - if ref == nil { + addressEndpoint := ndp.addAndAcquireSLAACAddr(generatedAddr, stack.AddressConfigSlaacTemp, false /* deprecated */) + if addressEndpoint == nil { return false } state := tempSLAACAddrState{ - deprecationJob: ndp.nic.stack.newJob(&ndp.nic.mu, func() { + deprecationJob: ndp.ep.stack.NewJob(&ndp.ep.mu, func() { prefixState, ok := ndp.slaacPrefixes[prefix] if !ok { panic(fmt.Sprintf("ndp: must have a slaacPrefixes entry for %s to deprecate temporary address %s", prefix, generatedAddr)) @@ -1427,9 +1444,9 @@ func (ndp *ndpState) generateTempSLAACAddr(prefix tcpip.Subnet, prefixState *sla panic(fmt.Sprintf("ndp: must have a tempAddr entry to deprecate temporary address %s", generatedAddr)) } - ndp.deprecateSLAACAddress(tempAddrState.ref) + ndp.deprecateSLAACAddress(tempAddrState.addressEndpoint) }), - invalidationJob: ndp.nic.stack.newJob(&ndp.nic.mu, func() { + invalidationJob: ndp.ep.stack.NewJob(&ndp.ep.mu, func() { prefixState, ok := ndp.slaacPrefixes[prefix] if !ok { panic(fmt.Sprintf("ndp: must have a slaacPrefixes entry for %s to invalidate temporary address %s", prefix, generatedAddr)) @@ -1442,7 +1459,7 @@ func (ndp *ndpState) generateTempSLAACAddr(prefix tcpip.Subnet, prefixState *sla ndp.invalidateTempSLAACAddr(prefixState.tempAddrs, generatedAddr.Address, tempAddrState) }), - regenJob: ndp.nic.stack.newJob(&ndp.nic.mu, func() { + regenJob: ndp.ep.stack.NewJob(&ndp.ep.mu, func() { prefixState, ok := ndp.slaacPrefixes[prefix] if !ok { panic(fmt.Sprintf("ndp: must have a slaacPrefixes entry for %s to regenerate temporary address after %s", prefix, generatedAddr)) @@ -1465,8 +1482,8 @@ func (ndp *ndpState) generateTempSLAACAddr(prefix tcpip.Subnet, prefixState *sla prefixState.tempAddrs[generatedAddr.Address] = tempAddrState ndp.slaacPrefixes[prefix] = prefixState }), - createdAt: now, - ref: ref, + createdAt: now, + addressEndpoint: addressEndpoint, } state.deprecationJob.Schedule(pl) @@ -1481,7 +1498,7 @@ func (ndp *ndpState) generateTempSLAACAddr(prefix tcpip.Subnet, prefixState *sla // regenerateTempSLAACAddr regenerates a temporary address for a SLAAC prefix. // -// The NIC that ndp belongs to MUST be locked. +// The IPv6 endpoint that ndp belongs to MUST be locked. func (ndp *ndpState) regenerateTempSLAACAddr(prefix tcpip.Subnet, resetGenAttempts bool) { state, ok := ndp.slaacPrefixes[prefix] if !ok { @@ -1496,14 +1513,14 @@ func (ndp *ndpState) regenerateTempSLAACAddr(prefix tcpip.Subnet, resetGenAttemp // // pl is the new preferred lifetime. vl is the new valid lifetime. // -// The NIC that ndp belongs to MUST be locked. +// The IPv6 endpoint that ndp belongs to MUST be locked. func (ndp *ndpState) refreshSLAACPrefixLifetimes(prefix tcpip.Subnet, prefixState *slaacPrefixState, pl, vl time.Duration) { // If the preferred lifetime is zero, then the prefix should be deprecated. deprecated := pl == 0 if deprecated { - ndp.deprecateSLAACAddress(prefixState.stableAddr.ref) + ndp.deprecateSLAACAddress(prefixState.stableAddr.addressEndpoint) } else { - prefixState.stableAddr.ref.deprecated = false + prefixState.stableAddr.addressEndpoint.SetDeprecated(false) } // If prefix was preferred for some finite lifetime before, cancel the @@ -1565,7 +1582,7 @@ func (ndp *ndpState) refreshSLAACPrefixLifetimes(prefix tcpip.Subnet, prefixStat // If DAD is not yet complete on the stable address, there is no need to do // work with temporary addresses. - if prefixState.stableAddr.ref.getKind() != permanent { + if prefixState.stableAddr.addressEndpoint.GetKind() != stack.Permanent { return } @@ -1608,9 +1625,9 @@ func (ndp *ndpState) refreshSLAACPrefixLifetimes(prefix tcpip.Subnet, prefixStat newPreferredLifetime := preferredUntil.Sub(now) tempAddrState.deprecationJob.Cancel() if newPreferredLifetime <= 0 { - ndp.deprecateSLAACAddress(tempAddrState.ref) + ndp.deprecateSLAACAddress(tempAddrState.addressEndpoint) } else { - tempAddrState.ref.deprecated = false + tempAddrState.addressEndpoint.SetDeprecated(false) tempAddrState.deprecationJob.Schedule(newPreferredLifetime) } @@ -1635,8 +1652,8 @@ func (ndp *ndpState) refreshSLAACPrefixLifetimes(prefix tcpip.Subnet, prefixStat // due to an update in preferred lifetime. // // If each temporay address has already been regenerated, no new temporary - // address will be generated. To ensure continuation of temporary SLAAC - // addresses, we manually try to regenerate an address here. + // address is generated. To ensure continuation of temporary SLAAC addresses, + // we manually try to regenerate an address here. if len(regenForAddr) != 0 || allAddressesRegenerated { // Reset the generation attempts counter as we are starting the generation // of a new address for the SLAAC prefix. @@ -1647,57 +1664,58 @@ func (ndp *ndpState) refreshSLAACPrefixLifetimes(prefix tcpip.Subnet, prefixStat } } -// deprecateSLAACAddress marks ref as deprecated and notifies the stack's NDP -// dispatcher that ref has been deprecated. +// deprecateSLAACAddress marks the address as deprecated and notifies the NDP +// dispatcher that address has been deprecated. // -// deprecateSLAACAddress does nothing if ref is already deprecated. +// deprecateSLAACAddress does nothing if the address is already deprecated. // -// The NIC that ndp belongs to MUST be locked. -func (ndp *ndpState) deprecateSLAACAddress(ref *referencedNetworkEndpoint) { - if ref.deprecated { +// The IPv6 endpoint that ndp belongs to MUST be locked. +func (ndp *ndpState) deprecateSLAACAddress(addressEndpoint stack.AddressEndpoint) { + if addressEndpoint.Deprecated() { return } - ref.deprecated = true - if ndpDisp := ndp.nic.stack.ndpDisp; ndpDisp != nil { - ndpDisp.OnAutoGenAddressDeprecated(ndp.nic.ID(), ref.addrWithPrefix()) + addressEndpoint.SetDeprecated(true) + if ndpDisp := ndp.ep.protocol.ndpDisp; ndpDisp != nil { + ndpDisp.OnAutoGenAddressDeprecated(ndp.ep.NICID(), addressEndpoint.AddressWithPrefix()) } } // invalidateSLAACPrefix invalidates a SLAAC prefix. // -// The NIC that ndp belongs to MUST be locked. +// The IPv6 endpoint that ndp belongs to MUST be locked. func (ndp *ndpState) invalidateSLAACPrefix(prefix tcpip.Subnet, state slaacPrefixState) { - if r := state.stableAddr.ref; r != nil { + ndp.cleanupSLAACPrefixResources(prefix, state) + + if addressEndpoint := state.stableAddr.addressEndpoint; addressEndpoint != nil { // Since we are already invalidating the prefix, do not invalidate the // prefix when removing the address. - if err := ndp.nic.removePermanentIPv6EndpointLocked(r, false /* allowSLAACInvalidation */); err != nil { - panic(fmt.Sprintf("ndp: error removing stable SLAAC address %s: %s", r.addrWithPrefix(), err)) + if err := ndp.ep.removePermanentEndpointLocked(addressEndpoint, false /* allowSLAACInvalidation */); err != nil { + panic(fmt.Sprintf("ndp: error removing stable SLAAC address %s: %s", addressEndpoint.AddressWithPrefix(), err)) } } - - ndp.cleanupSLAACPrefixResources(prefix, state) } // cleanupSLAACAddrResourcesAndNotify cleans up an invalidated SLAAC address's // resources. // -// The NIC that ndp belongs to MUST be locked. +// The IPv6 endpoint that ndp belongs to MUST be locked. func (ndp *ndpState) cleanupSLAACAddrResourcesAndNotify(addr tcpip.AddressWithPrefix, invalidatePrefix bool) { - if ndpDisp := ndp.nic.stack.ndpDisp; ndpDisp != nil { - ndpDisp.OnAutoGenAddressInvalidated(ndp.nic.ID(), addr) + if ndpDisp := ndp.ep.protocol.ndpDisp; ndpDisp != nil { + ndpDisp.OnAutoGenAddressInvalidated(ndp.ep.NICID(), addr) } prefix := addr.Subnet() state, ok := ndp.slaacPrefixes[prefix] - if !ok || state.stableAddr.ref == nil || addr.Address != state.stableAddr.ref.address() { + if !ok || state.stableAddr.addressEndpoint == nil || addr.Address != state.stableAddr.addressEndpoint.AddressWithPrefix().Address { return } if !invalidatePrefix { // If the prefix is not being invalidated, disassociate the address from the // prefix and do nothing further. - state.stableAddr.ref = nil + state.stableAddr.addressEndpoint.DecRef() + state.stableAddr.addressEndpoint = nil ndp.slaacPrefixes[prefix] = state return } @@ -1709,14 +1727,17 @@ func (ndp *ndpState) cleanupSLAACAddrResourcesAndNotify(addr tcpip.AddressWithPr // // Panics if the SLAAC prefix is not known. // -// The NIC that ndp belongs to MUST be locked. +// The IPv6 endpoint that ndp belongs to MUST be locked. func (ndp *ndpState) cleanupSLAACPrefixResources(prefix tcpip.Subnet, state slaacPrefixState) { // Invalidate all temporary addresses. for tempAddr, tempAddrState := range state.tempAddrs { ndp.invalidateTempSLAACAddr(state.tempAddrs, tempAddr, tempAddrState) } - state.stableAddr.ref = nil + if state.stableAddr.addressEndpoint != nil { + state.stableAddr.addressEndpoint.DecRef() + state.stableAddr.addressEndpoint = nil + } state.deprecationJob.Cancel() state.invalidationJob.Cancel() delete(ndp.slaacPrefixes, prefix) @@ -1724,12 +1745,12 @@ func (ndp *ndpState) cleanupSLAACPrefixResources(prefix tcpip.Subnet, state slaa // invalidateTempSLAACAddr invalidates a temporary SLAAC address. // -// The NIC that ndp belongs to MUST be locked. +// The IPv6 endpoint that ndp belongs to MUST be locked. func (ndp *ndpState) invalidateTempSLAACAddr(tempAddrs map[tcpip.Address]tempSLAACAddrState, tempAddr tcpip.Address, tempAddrState tempSLAACAddrState) { // Since we are already invalidating the address, do not invalidate the // address when removing the address. - if err := ndp.nic.removePermanentIPv6EndpointLocked(tempAddrState.ref, false /* allowSLAACInvalidation */); err != nil { - panic(fmt.Sprintf("error removing temporary SLAAC address %s: %s", tempAddrState.ref.addrWithPrefix(), err)) + if err := ndp.ep.removePermanentEndpointLocked(tempAddrState.addressEndpoint, false /* allowSLAACInvalidation */); err != nil { + panic(fmt.Sprintf("error removing temporary SLAAC address %s: %s", tempAddrState.addressEndpoint.AddressWithPrefix(), err)) } ndp.cleanupTempSLAACAddrResources(tempAddrs, tempAddr, tempAddrState) @@ -1738,10 +1759,10 @@ func (ndp *ndpState) invalidateTempSLAACAddr(tempAddrs map[tcpip.Address]tempSLA // cleanupTempSLAACAddrResourcesAndNotify cleans up an invalidated temporary // SLAAC address's resources from ndp. // -// The NIC that ndp belongs to MUST be locked. +// The IPv6 endpoint that ndp belongs to MUST be locked. func (ndp *ndpState) cleanupTempSLAACAddrResourcesAndNotify(addr tcpip.AddressWithPrefix, invalidateAddr bool) { - if ndpDisp := ndp.nic.stack.ndpDisp; ndpDisp != nil { - ndpDisp.OnAutoGenAddressInvalidated(ndp.nic.ID(), addr) + if ndpDisp := ndp.ep.protocol.ndpDisp; ndpDisp != nil { + ndpDisp.OnAutoGenAddressInvalidated(ndp.ep.NICID(), addr) } if !invalidateAddr { @@ -1765,35 +1786,29 @@ func (ndp *ndpState) cleanupTempSLAACAddrResourcesAndNotify(addr tcpip.AddressWi // cleanupTempSLAACAddrResourcesAndNotify cleans up a temporary SLAAC address's // jobs and entry. // -// The NIC that ndp belongs to MUST be locked. +// The IPv6 endpoint that ndp belongs to MUST be locked. func (ndp *ndpState) cleanupTempSLAACAddrResources(tempAddrs map[tcpip.Address]tempSLAACAddrState, tempAddr tcpip.Address, tempAddrState tempSLAACAddrState) { + tempAddrState.addressEndpoint.DecRef() + tempAddrState.addressEndpoint = nil tempAddrState.deprecationJob.Cancel() tempAddrState.invalidationJob.Cancel() tempAddrState.regenJob.Cancel() delete(tempAddrs, tempAddr) } -// cleanupState cleans up ndp's state. -// -// If hostOnly is true, then only host-specific state will be cleaned up. +// removeSLAACAddresses removes all SLAAC addresses. // -// cleanupState MUST be called with hostOnly set to true when ndp's NIC is -// transitioning from a host to a router. This function will invalidate all -// discovered on-link prefixes, discovered routers, and auto-generated -// addresses. -// -// If hostOnly is true, then the link-local auto-generated address will not be -// invalidated as routers are also expected to generate a link-local address. +// If keepLinkLocal is false, the SLAAC generated link-local address is removed. // -// The NIC that ndp belongs to MUST be locked. -func (ndp *ndpState) cleanupState(hostOnly bool) { +// The IPv6 endpoint that ndp belongs to MUST be locked. +func (ndp *ndpState) removeSLAACAddresses(keepLinkLocal bool) { linkLocalSubnet := header.IPv6LinkLocalPrefix.Subnet() - linkLocalPrefixes := 0 + var linkLocalPrefixes int for prefix, state := range ndp.slaacPrefixes { // RFC 4862 section 5 states that routers are also expected to generate a // link-local address so we do not invalidate them if we are cleaning up // host-only state. - if hostOnly && prefix == linkLocalSubnet { + if keepLinkLocal && prefix == linkLocalSubnet { linkLocalPrefixes++ continue } @@ -1804,6 +1819,21 @@ func (ndp *ndpState) cleanupState(hostOnly bool) { if got := len(ndp.slaacPrefixes); got != linkLocalPrefixes { panic(fmt.Sprintf("ndp: still have non-linklocal SLAAC prefixes after cleaning up; found = %d prefixes, of which %d are link-local", got, linkLocalPrefixes)) } +} + +// cleanupState cleans up ndp's state. +// +// If hostOnly is true, then only host-specific state is cleaned up. +// +// This function invalidates all discovered on-link prefixes, discovered +// routers, and auto-generated addresses. +// +// If hostOnly is true, then the link-local auto-generated address aren't +// invalidated as routers are also expected to generate a link-local address. +// +// The IPv6 endpoint that ndp belongs to MUST be locked. +func (ndp *ndpState) cleanupState(hostOnly bool) { + ndp.removeSLAACAddresses(hostOnly /* keepLinkLocal */) for prefix := range ndp.onLinkPrefixes { ndp.invalidateOnLinkPrefix(prefix) @@ -1827,7 +1857,7 @@ func (ndp *ndpState) cleanupState(hostOnly bool) { // startSolicitingRouters starts soliciting routers, as per RFC 4861 section // 6.3.7. If routers are already being solicited, this function does nothing. // -// The NIC ndp belongs to MUST be locked. +// The IPv6 endpoint that ndp belongs to MUST be locked. func (ndp *ndpState) startSolicitingRouters() { if ndp.rtrSolicit.timer != nil { // We are already soliciting routers. @@ -1848,27 +1878,37 @@ func (ndp *ndpState) startSolicitingRouters() { var done bool ndp.rtrSolicit.done = &done - ndp.rtrSolicit.timer = ndp.nic.stack.Clock().AfterFunc(delay, func() { - ndp.nic.mu.Lock() + ndp.rtrSolicit.timer = ndp.ep.stack.Clock().AfterFunc(delay, func() { + ndp.ep.mu.Lock() if done { // If we reach this point, it means that the RS timer fired after another - // goroutine already obtained the NIC lock and stopped solicitations. - // Simply return here and do nothing further. - ndp.nic.mu.Unlock() + // goroutine already obtained the IPv6 endpoint lock and stopped + // solicitations. Simply return here and do nothing further. + ndp.ep.mu.Unlock() return } // As per RFC 4861 section 4.1, the source of the RS is an address assigned // to the sending interface, or the unspecified address if no address is // assigned to the sending interface. - ref := ndp.nic.primaryIPv6EndpointRLocked(header.IPv6AllRoutersMulticastAddress) - if ref == nil { - ref = ndp.nic.getRefOrCreateTempLocked(header.IPv6ProtocolNumber, header.IPv6Any, NeverPrimaryEndpoint) + addressEndpoint := ndp.ep.acquirePrimaryAddressRLocked(header.IPv6AllRoutersMulticastAddress, false) + if addressEndpoint == nil { + // Incase this ends up creating a new temporary address, we need to hold + // onto the endpoint until a route is obtained. If we decrement the + // reference count before obtaing a route, the address's resources would + // be released and attempting to obtain a route after would fail. Once a + // route is obtainted, it is safe to decrement the reference count since + // obtaining a route increments the address's reference count. + addressEndpoint = ndp.ep.acquireAddressOrCreateTempLocked(header.IPv6Any, true /* createTemp */, stack.NeverPrimaryEndpoint) } - ndp.nic.mu.Unlock() + ndp.ep.mu.Unlock() - localAddr := ref.address() - r := makeRoute(header.IPv6ProtocolNumber, localAddr, header.IPv6AllRoutersMulticastAddress, ndp.nic.linkEP.LinkAddress(), ref, false, false) + localAddr := addressEndpoint.AddressWithPrefix().Address + r, err := ndp.ep.stack.FindRoute(ndp.ep.NICID(), localAddr, header.IPv6AllRoutersMulticastAddress, ProtocolNumber, false /* multicastLoop */) + addressEndpoint.DecRef() + if err != nil { + return + } defer r.Release() // Route should resolve immediately since @@ -1876,15 +1916,16 @@ func (ndp *ndpState) startSolicitingRouters() { // remote link address can be calculated without a resolution process. if c, err := r.Resolve(nil); err != nil { // Do not consider the NIC being unknown or disabled as a fatal error. - // Since this method is required to be called when the NIC is not locked, - // the NIC could have been disabled or removed by another goroutine. + // Since this method is required to be called when the IPv6 endpoint is + // not locked, the IPv6 endpoint could have been disabled or removed by + // another goroutine. if err == tcpip.ErrUnknownNICID || err == tcpip.ErrInvalidEndpointState { return } - panic(fmt.Sprintf("ndp: error when resolving route to send NDP RS (%s -> %s on NIC(%d)): %s", header.IPv6Any, header.IPv6AllRoutersMulticastAddress, ndp.nic.ID(), err)) + panic(fmt.Sprintf("ndp: error when resolving route to send NDP RS (%s -> %s on NIC(%d)): %s", header.IPv6Any, header.IPv6AllRoutersMulticastAddress, ndp.ep.NICID(), err)) } else if c != nil { - panic(fmt.Sprintf("ndp: route resolution not immediate for route to send NDP RS (%s -> %s on NIC(%d))", header.IPv6Any, header.IPv6AllRoutersMulticastAddress, ndp.nic.ID())) + panic(fmt.Sprintf("ndp: route resolution not immediate for route to send NDP RS (%s -> %s on NIC(%d))", header.IPv6Any, header.IPv6AllRoutersMulticastAddress, ndp.ep.NICID())) } // As per RFC 4861 section 4.1, an NDP RS SHOULD include the source @@ -1907,21 +1948,20 @@ func (ndp *ndpState) startSolicitingRouters() { rs.Options().Serialize(optsSerializer) icmpData.SetChecksum(header.ICMPv6Checksum(icmpData, r.LocalAddress, r.RemoteAddress, buffer.VectorisedView{})) - pkt := NewPacketBuffer(PacketBufferOptions{ + pkt := stack.NewPacketBuffer(stack.PacketBufferOptions{ ReserveHeaderBytes: int(r.MaxHeaderLength()), Data: buffer.View(icmpData).ToVectorisedView(), }) sent := r.Stats().ICMP.V6PacketsSent if err := r.WritePacket(nil, - NetworkHeaderParams{ + stack.NetworkHeaderParams{ Protocol: header.ICMPv6ProtocolNumber, TTL: header.NDPHopLimit, - TOS: DefaultTOS, }, pkt, ); err != nil { sent.Dropped.Increment() - log.Printf("startSolicitingRouters: error writing NDP router solicit message on NIC(%d); err = %s", ndp.nic.ID(), err) + log.Printf("startSolicitingRouters: error writing NDP router solicit message on NIC(%d); err = %s", ndp.ep.NICID(), err) // Don't send any more messages if we had an error. remaining = 0 } else { @@ -1929,19 +1969,19 @@ func (ndp *ndpState) startSolicitingRouters() { remaining-- } - ndp.nic.mu.Lock() + ndp.ep.mu.Lock() if done || remaining == 0 { ndp.rtrSolicit.timer = nil ndp.rtrSolicit.done = nil } else if ndp.rtrSolicit.timer != nil { // Note, we need to explicitly check to make sure that // the timer field is not nil because if it was nil but - // we still reached this point, then we know the NIC + // we still reached this point, then we know the IPv6 endpoint // was requested to stop soliciting routers so we don't // need to send the next Router Solicitation message. ndp.rtrSolicit.timer.Reset(ndp.configs.RtrSolicitationInterval) } - ndp.nic.mu.Unlock() + ndp.ep.mu.Unlock() }) } @@ -1949,7 +1989,7 @@ func (ndp *ndpState) startSolicitingRouters() { // stopSolicitingRouters stops soliciting routers. If routers are not currently // being solicited, this function does nothing. // -// The NIC ndp belongs to MUST be locked. +// The IPv6 endpoint that ndp belongs to MUST be locked. func (ndp *ndpState) stopSolicitingRouters() { if ndp.rtrSolicit.timer == nil { // Nothing to do. @@ -1965,7 +2005,7 @@ func (ndp *ndpState) stopSolicitingRouters() { // initializeTempAddrState initializes state related to temporary SLAAC // addresses. func (ndp *ndpState) initializeTempAddrState() { - header.InitialTempIID(ndp.temporaryIIDHistory[:], ndp.nic.stack.tempIIDSeed, ndp.nic.ID()) + header.InitialTempIID(ndp.temporaryIIDHistory[:], ndp.ep.protocol.tempIIDSeed, ndp.ep.NICID()) if MaxDesyncFactor != 0 { ndp.temporaryAddressDesyncFactor = time.Duration(rand.Int63n(int64(MaxDesyncFactor))) diff --git a/pkg/tcpip/stack/addressable_endpoint_state.go b/pkg/tcpip/stack/addressable_endpoint_state.go new file mode 100644 index 000000000..270ac4977 --- /dev/null +++ b/pkg/tcpip/stack/addressable_endpoint_state.go @@ -0,0 +1,717 @@ +// 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 stack + +import ( + "fmt" + + "gvisor.dev/gvisor/pkg/sync" + "gvisor.dev/gvisor/pkg/tcpip" +) + +var _ GroupAddressableEndpoint = (*AddressableEndpointState)(nil) +var _ AddressableEndpoint = (*AddressableEndpointState)(nil) + +// AddressableEndpointState is an implementation of an AddressableEndpoint. +type AddressableEndpointState struct { + networkEndpoint NetworkEndpoint + + // Lock ordering (from outer to inner lock ordering): + // + // AddressableEndpointState.mu + // addressState.mu + mu struct { + sync.RWMutex + + endpoints map[tcpip.Address]*addressState + primary []*addressState + + // groups holds the mapping between group addresses and the number of times + // they have been joined. + groups map[tcpip.Address]uint32 + } +} + +// Init initializes the AddressableEndpointState with networkEndpoint. +// +// Must be called before calling any other function on m. +func (a *AddressableEndpointState) Init(networkEndpoint NetworkEndpoint) { + a.networkEndpoint = networkEndpoint + + a.mu.Lock() + defer a.mu.Unlock() + a.mu.endpoints = make(map[tcpip.Address]*addressState) + a.mu.groups = make(map[tcpip.Address]uint32) +} + +// ReadOnlyAddressableEndpointState provides read-only access to an +// AddressableEndpointState. +type ReadOnlyAddressableEndpointState struct { + inner *AddressableEndpointState +} + +// AddrOrMatching returns an endpoint for the passed address that is consisdered +// bound to the wrapped AddressableEndpointState. +// +// If addr is an exact match with an existing address, that address is returned. +// Otherwise, f is called with each address and the address that f returns true +// for is returned. +// +// Returns nil of no address matches. +func (m ReadOnlyAddressableEndpointState) AddrOrMatching(addr tcpip.Address, spoofingOrPrimiscuous bool, f func(AddressEndpoint) bool) AddressEndpoint { + m.inner.mu.RLock() + defer m.inner.mu.RUnlock() + + if ep, ok := m.inner.mu.endpoints[addr]; ok { + if ep.IsAssigned(spoofingOrPrimiscuous) && ep.IncRef() { + return ep + } + } + + for _, ep := range m.inner.mu.endpoints { + if ep.IsAssigned(spoofingOrPrimiscuous) && f(ep) && ep.IncRef() { + return ep + } + } + + return nil +} + +// Lookup returns the AddressEndpoint for the passed address. +// +// Returns nil if the passed address is not associated with the +// AddressableEndpointState. +func (m ReadOnlyAddressableEndpointState) Lookup(addr tcpip.Address) AddressEndpoint { + m.inner.mu.RLock() + defer m.inner.mu.RUnlock() + + ep, ok := m.inner.mu.endpoints[addr] + if !ok { + return nil + } + return ep +} + +// ForEach calls f for each address pair. +// +// If f returns false, f is no longer be called. +func (m ReadOnlyAddressableEndpointState) ForEach(f func(AddressEndpoint) bool) { + m.inner.mu.RLock() + defer m.inner.mu.RUnlock() + + for _, ep := range m.inner.mu.endpoints { + if !f(ep) { + return + } + } +} + +// ForEachPrimaryEndpoint calls f for each primary address. +// +// If f returns false, f is no longer be called. +func (m ReadOnlyAddressableEndpointState) ForEachPrimaryEndpoint(f func(AddressEndpoint)) { + m.inner.mu.RLock() + defer m.inner.mu.RUnlock() + for _, ep := range m.inner.mu.primary { + f(ep) + } +} + +// ReadOnly returns a readonly reference to a. +func (a *AddressableEndpointState) ReadOnly() ReadOnlyAddressableEndpointState { + return ReadOnlyAddressableEndpointState{inner: a} +} + +func (a *AddressableEndpointState) releaseAddressState(addrState *addressState) { + a.mu.Lock() + defer a.mu.Unlock() + a.releaseAddressStateLocked(addrState) +} + +// releaseAddressState removes addrState from s's address state (primary and endpoints list). +// +// Preconditions: a.mu must be write locked. +func (a *AddressableEndpointState) releaseAddressStateLocked(addrState *addressState) { + oldPrimary := a.mu.primary + for i, s := range a.mu.primary { + if s == addrState { + a.mu.primary = append(a.mu.primary[:i], a.mu.primary[i+1:]...) + oldPrimary[len(oldPrimary)-1] = nil + break + } + } + delete(a.mu.endpoints, addrState.addr.Address) +} + +// AddAndAcquirePermanentAddress implements AddressableEndpoint. +func (a *AddressableEndpointState) AddAndAcquirePermanentAddress(addr tcpip.AddressWithPrefix, peb PrimaryEndpointBehavior, configType AddressConfigType, deprecated bool) (AddressEndpoint, *tcpip.Error) { + a.mu.Lock() + defer a.mu.Unlock() + ep, err := a.addAndAcquireAddressLocked(addr, peb, configType, deprecated, true /* permanent */) + // From https://golang.org/doc/faq#nil_error: + // + // Under the covers, interfaces are implemented as two elements, a type T and + // a value V. + // + // An interface value is nil only if the V and T are both unset, (T=nil, V is + // not set), In particular, a nil interface will always hold a nil type. If we + // store a nil pointer of type *int inside an interface value, the inner type + // will be *int regardless of the value of the pointer: (T=*int, V=nil). Such + // an interface value will therefore be non-nil even when the pointer value V + // inside is nil. + // + // Since addAndAcquireAddressLocked returns a nil value with a non-nil type, + // we need to explicitly return nil below if ep is (a typed) nil. + if ep == nil { + return nil, err + } + return ep, err +} + +// AddAndAcquireTemporaryAddress adds a temporary address. +// +// Returns tcpip.ErrDuplicateAddress if the address exists. +// +// The temporary address's endpoint is acquired and returned. +func (a *AddressableEndpointState) AddAndAcquireTemporaryAddress(addr tcpip.AddressWithPrefix, peb PrimaryEndpointBehavior) (AddressEndpoint, *tcpip.Error) { + a.mu.Lock() + defer a.mu.Unlock() + ep, err := a.addAndAcquireAddressLocked(addr, peb, AddressConfigStatic, false /* deprecated */, false /* permanent */) + // From https://golang.org/doc/faq#nil_error: + // + // Under the covers, interfaces are implemented as two elements, a type T and + // a value V. + // + // An interface value is nil only if the V and T are both unset, (T=nil, V is + // not set), In particular, a nil interface will always hold a nil type. If we + // store a nil pointer of type *int inside an interface value, the inner type + // will be *int regardless of the value of the pointer: (T=*int, V=nil). Such + // an interface value will therefore be non-nil even when the pointer value V + // inside is nil. + // + // Since addAndAcquireAddressLocked returns a nil value with a non-nil type, + // we need to explicitly return nil below if ep is (a typed) nil. + if ep == nil { + return nil, err + } + return ep, err +} + +// addAndAcquireAddressLocked adds, acquires and returns a permanent or +// temporary address. +// +// If the addressable endpoint already has the address in a non-permanent state, +// and addAndAcquireAddressLocked is adding a permanent address, that address is +// promoted in place and its properties set to the properties provided. If the +// address already exists in any other state, then tcpip.ErrDuplicateAddress is +// returned, regardless the kind of address that is being added. +// +// Precondition: a.mu must be write locked. +func (a *AddressableEndpointState) addAndAcquireAddressLocked(addr tcpip.AddressWithPrefix, peb PrimaryEndpointBehavior, configType AddressConfigType, deprecated, permanent bool) (*addressState, *tcpip.Error) { + // attemptAddToPrimary is false when the address is already in the primary + // address list. + attemptAddToPrimary := true + addrState, ok := a.mu.endpoints[addr.Address] + if ok { + if !permanent { + // We are adding a non-permanent address but the address exists. No need + // to go any further since we can only promote existing temporary/expired + // addresses to permanent. + return nil, tcpip.ErrDuplicateAddress + } + + addrState.mu.Lock() + if addrState.mu.kind.IsPermanent() { + addrState.mu.Unlock() + // We are adding a permanent address but a permanent address already + // exists. + return nil, tcpip.ErrDuplicateAddress + } + + if addrState.mu.refs == 0 { + panic(fmt.Sprintf("found an address that should have been released (ref count == 0); address = %s", addrState.addr)) + } + + // We now promote the address. + for i, s := range a.mu.primary { + if s == addrState { + switch peb { + case CanBePrimaryEndpoint: + // The address is already in the primary address list. + attemptAddToPrimary = false + case FirstPrimaryEndpoint: + if i == 0 { + // The address is already first in the primary address list. + attemptAddToPrimary = false + } else { + a.mu.primary = append(a.mu.primary[:i], a.mu.primary[i+1:]...) + } + case NeverPrimaryEndpoint: + a.mu.primary = append(a.mu.primary[:i], a.mu.primary[i+1:]...) + default: + panic(fmt.Sprintf("unrecognized primary endpoint behaviour = %d", peb)) + } + break + } + } + } + + if addrState == nil { + addrState = &addressState{ + addressableEndpointState: a, + addr: addr, + } + a.mu.endpoints[addr.Address] = addrState + addrState.mu.Lock() + // We never promote an address to temporary - it can only be added as such. + // If we are actaully adding a permanent address, it is promoted below. + addrState.mu.kind = Temporary + } + + // At this point we have an address we are either promoting from an expired or + // temporary address to permanent, promoting an expired address to temporary, + // or we are adding a new temporary or permanent address. + // + // The address MUST be write locked at this point. + defer addrState.mu.Unlock() + + if permanent { + if addrState.mu.kind.IsPermanent() { + panic(fmt.Sprintf("only non-permanent addresses should be promoted to permanent; address = %s", addrState.addr)) + } + + // Primary addresses are biased by 1. + addrState.mu.refs++ + addrState.mu.kind = Permanent + } + // Acquire the address before returning it. + addrState.mu.refs++ + addrState.mu.deprecated = deprecated + addrState.mu.configType = configType + + if attemptAddToPrimary { + switch peb { + case NeverPrimaryEndpoint: + case CanBePrimaryEndpoint: + a.mu.primary = append(a.mu.primary, addrState) + case FirstPrimaryEndpoint: + if cap(a.mu.primary) == len(a.mu.primary) { + a.mu.primary = append([]*addressState{addrState}, a.mu.primary...) + } else { + // Shift all the endpoints by 1 to make room for the new address at the + // front. We could have just created a new slice but this saves + // allocations when the slice has capacity for the new address. + primaryCount := len(a.mu.primary) + a.mu.primary = append(a.mu.primary, nil) + if n := copy(a.mu.primary[1:], a.mu.primary); n != primaryCount { + panic(fmt.Sprintf("copied %d elements; expected = %d elements", n, primaryCount)) + } + a.mu.primary[0] = addrState + } + default: + panic(fmt.Sprintf("unrecognized primary endpoint behaviour = %d", peb)) + } + } + + return addrState, nil +} + +// RemovePermanentAddress implements AddressableEndpoint. +func (a *AddressableEndpointState) RemovePermanentAddress(addr tcpip.Address) *tcpip.Error { + a.mu.Lock() + defer a.mu.Unlock() + + if _, ok := a.mu.groups[addr]; ok { + panic(fmt.Sprintf("group address = %s must be removed with LeaveGroup", addr)) + } + + return a.removePermanentAddressLocked(addr) +} + +// removePermanentAddressLocked is like RemovePermanentAddress but with locking +// requirements. +// +// Precondition: a.mu must be write locked. +func (a *AddressableEndpointState) removePermanentAddressLocked(addr tcpip.Address) *tcpip.Error { + addrState, ok := a.mu.endpoints[addr] + if !ok { + return tcpip.ErrBadLocalAddress + } + + return a.removePermanentEndpointLocked(addrState) +} + +// RemovePermanentEndpoint removes the passed endpoint if it is associated with +// a and permanent. +func (a *AddressableEndpointState) RemovePermanentEndpoint(ep AddressEndpoint) *tcpip.Error { + addrState, ok := ep.(*addressState) + if !ok || addrState.addressableEndpointState != a { + return tcpip.ErrInvalidEndpointState + } + + return a.removePermanentEndpointLocked(addrState) +} + +// removePermanentAddressLocked is like RemovePermanentAddress but with locking +// requirements. +// +// Precondition: a.mu must be write locked. +func (a *AddressableEndpointState) removePermanentEndpointLocked(addrState *addressState) *tcpip.Error { + if !addrState.GetKind().IsPermanent() { + return tcpip.ErrBadLocalAddress + } + + addrState.SetKind(PermanentExpired) + a.decAddressRefLocked(addrState) + return nil +} + +// decAddressRef decrements the address's reference count and releases it once +// the reference count hits 0. +func (a *AddressableEndpointState) decAddressRef(addrState *addressState) { + a.mu.Lock() + defer a.mu.Unlock() + a.decAddressRefLocked(addrState) +} + +// decAddressRefLocked is like decAddressRef but with locking requirements. +// +// Precondition: a.mu must be write locked. +func (a *AddressableEndpointState) decAddressRefLocked(addrState *addressState) { + addrState.mu.Lock() + defer addrState.mu.Unlock() + + if addrState.mu.refs == 0 { + panic(fmt.Sprintf("attempted to decrease ref count for AddressEndpoint w/ addr = %s when it is already released", addrState.addr)) + } + + addrState.mu.refs-- + + if addrState.mu.refs != 0 { + return + } + + // A non-expired permanent address must not have its reference count dropped + // to 0. + if addrState.mu.kind.IsPermanent() { + panic(fmt.Sprintf("permanent addresses should be removed through the AddressableEndpoint: addr = %s, kind = %d", addrState.addr, addrState.mu.kind)) + } + + a.releaseAddressStateLocked(addrState) +} + +// AcquireAssignedAddress implements AddressableEndpoint. +func (a *AddressableEndpointState) AcquireAssignedAddress(localAddr tcpip.Address, allowTemp bool, tempPEB PrimaryEndpointBehavior) AddressEndpoint { + a.mu.Lock() + defer a.mu.Unlock() + + if addrState, ok := a.mu.endpoints[localAddr]; ok { + if !addrState.IsAssigned(allowTemp) { + return nil + } + + if !addrState.IncRef() { + panic(fmt.Sprintf("failed to increase the reference count for address = %s", addrState.addr)) + } + + return addrState + } + + if !allowTemp { + return nil + } + + addr := localAddr.WithPrefix() + ep, err := a.addAndAcquireAddressLocked(addr, tempPEB, AddressConfigStatic, false /* deprecated */, false /* permanent */) + if err != nil { + // addAndAcquireAddressLocked only returns an error if the address is + // already assigned but we just checked above if the address exists so we + // expect no error. + panic(fmt.Sprintf("a.addAndAcquireAddressLocked(%s, %d, %d, false, false): %s", addr, tempPEB, AddressConfigStatic, err)) + } + // From https://golang.org/doc/faq#nil_error: + // + // Under the covers, interfaces are implemented as two elements, a type T and + // a value V. + // + // An interface value is nil only if the V and T are both unset, (T=nil, V is + // not set), In particular, a nil interface will always hold a nil type. If we + // store a nil pointer of type *int inside an interface value, the inner type + // will be *int regardless of the value of the pointer: (T=*int, V=nil). Such + // an interface value will therefore be non-nil even when the pointer value V + // inside is nil. + // + // Since addAndAcquireAddressLocked returns a nil value with a non-nil type, + // we need to explicitly return nil below if ep is (a typed) nil. + if ep == nil { + return nil + } + return ep +} + +// AcquirePrimaryAddress implements AddressableEndpoint. +func (a *AddressableEndpointState) AcquirePrimaryAddress(remoteAddr tcpip.Address, allowExpired bool) AddressEndpoint { + a.mu.RLock() + defer a.mu.RUnlock() + + var deprecatedEndpoint *addressState + for _, ep := range a.mu.primary { + if !ep.IsAssigned(allowExpired) { + continue + } + + if !ep.Deprecated() { + if ep.IncRef() { + // ep is not deprecated, so return it immediately. + // + // If we kept track of a deprecated endpoint, decrement its reference + // count since it was incremented when we decided to keep track of it. + if deprecatedEndpoint != nil { + a.decAddressRefLocked(deprecatedEndpoint) + deprecatedEndpoint = nil + } + + return ep + } + } else if deprecatedEndpoint == nil && ep.IncRef() { + // We prefer an endpoint that is not deprecated, but we keep track of + // ep in case a doesn't have any non-deprecated endpoints. + // + // If we end up finding a more preferred endpoint, ep's reference count + // will be decremented. + deprecatedEndpoint = ep + } + } + + // a doesn't have any valid non-deprecated endpoints, so return + // deprecatedEndpoint (which may be nil if a doesn't have any valid deprecated + // endpoints either). + if deprecatedEndpoint == nil { + return nil + } + return deprecatedEndpoint +} + +// PrimaryAddresses implements AddressableEndpoint. +func (a *AddressableEndpointState) PrimaryAddresses() []tcpip.AddressWithPrefix { + a.mu.RLock() + defer a.mu.RUnlock() + + var addrs []tcpip.AddressWithPrefix + for _, ep := range a.mu.primary { + // Don't include tentative, expired or temporary endpoints + // to avoid confusion and prevent the caller from using + // those. + switch ep.GetKind() { + case PermanentTentative, PermanentExpired, Temporary: + continue + } + + addrs = append(addrs, ep.AddressWithPrefix()) + } + + return addrs +} + +// PermanentAddresses implements AddressableEndpoint. +func (a *AddressableEndpointState) PermanentAddresses() []tcpip.AddressWithPrefix { + a.mu.RLock() + defer a.mu.RUnlock() + + var addrs []tcpip.AddressWithPrefix + for _, ep := range a.mu.endpoints { + if !ep.GetKind().IsPermanent() { + continue + } + + addrs = append(addrs, ep.AddressWithPrefix()) + } + + return addrs +} + +// JoinGroup implements GroupAddressableEndpoint. +func (a *AddressableEndpointState) JoinGroup(group tcpip.Address) (bool, *tcpip.Error) { + a.mu.Lock() + defer a.mu.Unlock() + + joins, ok := a.mu.groups[group] + if !ok { + ep, err := a.addAndAcquireAddressLocked(group.WithPrefix(), NeverPrimaryEndpoint, AddressConfigStatic, false /* deprecated */, true /* permanent */) + if err != nil { + return false, err + } + // We have no need for the address endpoint. + a.decAddressRefLocked(ep) + } + + a.mu.groups[group] = joins + 1 + return !ok, nil +} + +// LeaveGroup implements GroupAddressableEndpoint. +func (a *AddressableEndpointState) LeaveGroup(group tcpip.Address) (bool, *tcpip.Error) { + a.mu.Lock() + defer a.mu.Unlock() + + joins, ok := a.mu.groups[group] + if !ok { + return false, tcpip.ErrBadLocalAddress + } + + if joins == 1 { + a.removeGroupAddressLocked(group) + delete(a.mu.groups, group) + return true, nil + } + + a.mu.groups[group] = joins - 1 + return false, nil +} + +// IsInGroup implements GroupAddressableEndpoint. +func (a *AddressableEndpointState) IsInGroup(group tcpip.Address) bool { + a.mu.RLock() + defer a.mu.RUnlock() + _, ok := a.mu.groups[group] + return ok +} + +func (a *AddressableEndpointState) removeGroupAddressLocked(group tcpip.Address) { + if err := a.removePermanentAddressLocked(group); err != nil { + // removePermanentEndpointLocked would only return an error if group is + // not bound to the addressable endpoint, but we know it MUST be assigned + // since we have group in our map of groups. + panic(fmt.Sprintf("error removing group address = %s: %s", group, err)) + } +} + +// Cleanup forcefully leaves all groups and removes all permanent addresses. +func (a *AddressableEndpointState) Cleanup() { + a.mu.Lock() + defer a.mu.Unlock() + + for group := range a.mu.groups { + a.removeGroupAddressLocked(group) + } + a.mu.groups = make(map[tcpip.Address]uint32) + + for _, ep := range a.mu.endpoints { + // removePermanentEndpointLocked returns tcpip.ErrBadLocalAddress if ep is + // not a permanent address. + if err := a.removePermanentEndpointLocked(ep); err != nil && err != tcpip.ErrBadLocalAddress { + panic(fmt.Sprintf("unexpected error from removePermanentEndpointLocked(%s): %s", ep.addr, err)) + } + } +} + +var _ AddressEndpoint = (*addressState)(nil) + +// addressState holds state for an address. +type addressState struct { + addressableEndpointState *AddressableEndpointState + addr tcpip.AddressWithPrefix + + // Lock ordering (from outer to inner lock ordering): + // + // AddressableEndpointState.mu + // addressState.mu + mu struct { + sync.RWMutex + + refs uint32 + kind AddressKind + configType AddressConfigType + deprecated bool + } +} + +// NetworkEndpoint implements AddressEndpoint. +func (a *addressState) NetworkEndpoint() NetworkEndpoint { + return a.addressableEndpointState.networkEndpoint +} + +// AddressWithPrefix implements AddressEndpoint. +func (a *addressState) AddressWithPrefix() tcpip.AddressWithPrefix { + return a.addr +} + +// GetKind implements AddressEndpoint. +func (a *addressState) GetKind() AddressKind { + a.mu.RLock() + defer a.mu.RUnlock() + return a.mu.kind +} + +// SetKind implements AddressEndpoint. +func (a *addressState) SetKind(kind AddressKind) { + a.mu.Lock() + defer a.mu.Unlock() + a.mu.kind = kind +} + +// IsAssigned implements AddressEndpoint. +func (a *addressState) IsAssigned(allowExpired bool) bool { + if !a.addressableEndpointState.networkEndpoint.Enabled() { + return false + } + + switch a.GetKind() { + case PermanentTentative: + return false + case PermanentExpired: + return allowExpired + default: + return true + } +} + +// IncRef implements AddressEndpoint. +func (a *addressState) IncRef() bool { + a.mu.Lock() + defer a.mu.Unlock() + if a.mu.refs == 0 { + return false + } + + a.mu.refs++ + return true +} + +// DecRef implements AddressEndpoint. +func (a *addressState) DecRef() { + a.addressableEndpointState.decAddressRef(a) +} + +// ConfigType implements AddressEndpoint. +func (a *addressState) ConfigType() AddressConfigType { + a.mu.RLock() + defer a.mu.RUnlock() + return a.mu.configType +} + +// SetDeprecated implements AddressEndpoint. +func (a *addressState) SetDeprecated(d bool) { + a.mu.Lock() + defer a.mu.Unlock() + a.mu.deprecated = d +} + +// Deprecated implements AddressEndpoint. +func (a *addressState) Deprecated() bool { + a.mu.RLock() + defer a.mu.RUnlock() + return a.mu.deprecated +} diff --git a/pkg/tcpip/stack/neighbor_entry.go b/pkg/tcpip/stack/neighbor_entry.go index 213646160..9a72bec79 100644 --- a/pkg/tcpip/stack/neighbor_entry.go +++ b/pkg/tcpip/stack/neighbor_entry.go @@ -21,6 +21,7 @@ import ( "gvisor.dev/gvisor/pkg/sleep" "gvisor.dev/gvisor/pkg/tcpip" + "gvisor.dev/gvisor/pkg/tcpip/header" ) // NeighborEntry describes a neighboring device in the local network. @@ -439,7 +440,7 @@ func (e *neighborEntry) handleConfirmationLocked(linkAddr tcpip.LinkAddress, fla e.notifyWakersLocked() } - if e.isRouter && !flags.IsRouter { + if e.isRouter && !flags.IsRouter && header.IsV6UnicastAddress(e.neigh.Addr) { // "In those cases where the IsRouter flag changes from TRUE to FALSE as // a result of this update, the node MUST remove that router from the // Default Router List and update the Destination Cache entries for all @@ -447,9 +448,17 @@ func (e *neighborEntry) handleConfirmationLocked(linkAddr tcpip.LinkAddress, fla // 7.3.3. This is needed to detect when a node that is used as a router // stops forwarding packets due to being configured as a host." // - RFC 4861 section 7.2.5 - e.nic.mu.Lock() - e.nic.mu.ndp.invalidateDefaultRouter(e.neigh.Addr) - e.nic.mu.Unlock() + // + // TODO(gvisor.dev/issue/4085): Remove the special casing we do for IPv6 + // here. + ep, ok := e.nic.networkEndpoints[header.IPv6ProtocolNumber] + if !ok { + panic(fmt.Sprintf("have a neighbor entry for an IPv6 router but no IPv6 network endpoint")) + } + + if ndpEP, ok := ep.(NDPEndpoint); ok { + ndpEP.InvalidateDefaultRouter(e.neigh.Addr) + } } e.isRouter = flags.IsRouter diff --git a/pkg/tcpip/stack/nic.go b/pkg/tcpip/stack/nic.go index 2875a5b60..926ce9cfc 100644 --- a/pkg/tcpip/stack/nic.go +++ b/pkg/tcpip/stack/nic.go @@ -18,7 +18,6 @@ import ( "fmt" "math/rand" "reflect" - "sort" "sync/atomic" "gvisor.dev/gvisor/pkg/sleep" @@ -28,13 +27,7 @@ import ( "gvisor.dev/gvisor/pkg/tcpip/header" ) -var ipv4BroadcastAddr = tcpip.ProtocolAddress{ - Protocol: header.IPv4ProtocolNumber, - AddressWithPrefix: tcpip.AddressWithPrefix{ - Address: header.IPv4Broadcast, - PrefixLen: 8 * header.IPv4AddressSize, - }, -} +var _ NetworkInterface = (*NIC)(nil) // NIC represents a "network interface card" to which the networking stack is // attached. @@ -49,18 +42,18 @@ type NIC struct { neigh *neighborCache networkEndpoints map[tcpip.NetworkProtocolNumber]NetworkEndpoint + // enabled is set to 1 when the NIC is enabled and 0 when it is disabled. + // + // Must be accessed using atomic operations. + enabled uint32 + mu struct { sync.RWMutex - enabled bool spoofing bool promiscuous bool - primary map[tcpip.NetworkProtocolNumber][]*referencedNetworkEndpoint - endpoints map[NetworkEndpointID]*referencedNetworkEndpoint - mcastJoins map[NetworkEndpointID]uint32 // packetEPs is protected by mu, but the contained PacketEndpoint // values are not. packetEPs map[tcpip.NetworkProtocolNumber][]PacketEndpoint - ndp ndpState } } @@ -84,25 +77,6 @@ type DirectionStats struct { Bytes *tcpip.StatCounter } -// PrimaryEndpointBehavior is an enumeration of an endpoint's primacy behavior. -type PrimaryEndpointBehavior int - -const ( - // CanBePrimaryEndpoint indicates the endpoint can be used as a primary - // endpoint for new connections with no local address. This is the - // default when calling NIC.AddAddress. - CanBePrimaryEndpoint PrimaryEndpointBehavior = iota - - // FirstPrimaryEndpoint indicates the endpoint should be the first - // primary endpoint considered. If there are multiple endpoints with - // this behavior, the most recently-added one will be first. - FirstPrimaryEndpoint - - // NeverPrimaryEndpoint indicates the endpoint should never be a - // primary endpoint. - NeverPrimaryEndpoint -) - // newNIC returns a new NIC using the default NDP configurations from stack. func newNIC(stack *Stack, id tcpip.NICID, name string, ep LinkEndpoint, ctx NICContext) *NIC { // TODO(b/141011931): Validate a LinkEndpoint (ep) is valid. For @@ -122,19 +96,7 @@ func newNIC(stack *Stack, id tcpip.NICID, name string, ep LinkEndpoint, ctx NICC stats: makeNICStats(), networkEndpoints: make(map[tcpip.NetworkProtocolNumber]NetworkEndpoint), } - nic.mu.primary = make(map[tcpip.NetworkProtocolNumber][]*referencedNetworkEndpoint) - nic.mu.endpoints = make(map[NetworkEndpointID]*referencedNetworkEndpoint) - nic.mu.mcastJoins = make(map[NetworkEndpointID]uint32) nic.mu.packetEPs = make(map[tcpip.NetworkProtocolNumber][]PacketEndpoint) - nic.mu.ndp = ndpState{ - nic: nic, - configs: stack.ndpConfigs, - dad: make(map[tcpip.Address]dadState), - defaultRouters: make(map[tcpip.Address]defaultRouterState), - onLinkPrefixes: make(map[tcpip.Subnet]onLinkPrefixState), - slaacPrefixes: make(map[tcpip.Subnet]slaacPrefixState), - } - nic.mu.ndp.initializeTempAddrState() // Check for Neighbor Unreachability Detection support. var nud NUDHandler @@ -162,7 +124,7 @@ func newNIC(stack *Stack, id tcpip.NICID, name string, ep LinkEndpoint, ctx NICC for _, netProto := range stack.networkProtocols { netNum := netProto.Number() nic.mu.packetEPs[netNum] = nil - nic.networkEndpoints[netNum] = netProto.NewEndpoint(id, stack, nud, nic, ep, stack) + nic.networkEndpoints[netNum] = netProto.NewEndpoint(nic, stack, nud, nic, ep, stack) } nic.linkEP.Attach(nic) @@ -170,29 +132,28 @@ func newNIC(stack *Stack, id tcpip.NICID, name string, ep LinkEndpoint, ctx NICC return nic } -// enabled returns true if n is enabled. -func (n *NIC) enabled() bool { - n.mu.RLock() - enabled := n.mu.enabled - n.mu.RUnlock() - return enabled +// Enabled implements NetworkInterface. +func (n *NIC) Enabled() bool { + return atomic.LoadUint32(&n.enabled) == 1 } -// disable disables n. +// setEnabled sets the enabled status for the NIC. // -// It undoes the work done by enable. -func (n *NIC) disable() *tcpip.Error { - n.mu.RLock() - enabled := n.mu.enabled - n.mu.RUnlock() - if !enabled { - return nil +// Returns true if the enabled status was updated. +func (n *NIC) setEnabled(v bool) bool { + if v { + return atomic.SwapUint32(&n.enabled, 1) == 0 } + return atomic.SwapUint32(&n.enabled, 0) == 1 +} +// disable disables n. +// +// It undoes the work done by enable. +func (n *NIC) disable() { n.mu.Lock() - err := n.disableLocked() + n.disableLocked() n.mu.Unlock() - return err } // disableLocked disables n. @@ -200,9 +161,9 @@ func (n *NIC) disable() *tcpip.Error { // It undoes the work done by enable. // // n MUST be locked. -func (n *NIC) disableLocked() *tcpip.Error { - if !n.mu.enabled { - return nil +func (n *NIC) disableLocked() { + if !n.setEnabled(false) { + return } // TODO(gvisor.dev/issue/1491): Should Routes that are currently bound to n be @@ -210,38 +171,9 @@ func (n *NIC) disableLocked() *tcpip.Error { // again, and applications may not know that the underlying NIC was ever // disabled. - if _, ok := n.stack.networkProtocols[header.IPv6ProtocolNumber]; ok { - n.mu.ndp.stopSolicitingRouters() - n.mu.ndp.cleanupState(false /* hostOnly */) - - // Stop DAD for all the unicast IPv6 endpoints that are in the - // permanentTentative state. - for _, r := range n.mu.endpoints { - if addr := r.address(); r.getKind() == permanentTentative && header.IsV6UnicastAddress(addr) { - n.mu.ndp.stopDuplicateAddressDetection(addr) - } - } - - // The NIC may have already left the multicast group. - if err := n.leaveGroupLocked(header.IPv6AllNodesMulticastAddress, false /* force */); err != nil && err != tcpip.ErrBadLocalAddress { - return err - } - } - - if _, ok := n.stack.networkProtocols[header.IPv4ProtocolNumber]; ok { - // The NIC may have already left the multicast group. - if err := n.leaveGroupLocked(header.IPv4AllSystems, false /* force */); err != nil && err != tcpip.ErrBadLocalAddress { - return err - } - - // The address may have already been removed. - if err := n.removePermanentAddressLocked(ipv4BroadcastAddr.AddressWithPrefix.Address); err != nil && err != tcpip.ErrBadLocalAddress { - return err - } + for _, ep := range n.networkEndpoints { + ep.Disable() } - - n.mu.enabled = false - return nil } // enable enables n. @@ -251,162 +183,39 @@ func (n *NIC) disableLocked() *tcpip.Error { // routers if the stack is not operating as a router. If the stack is also // configured to auto-generate a link-local address, one will be generated. func (n *NIC) enable() *tcpip.Error { - n.mu.RLock() - enabled := n.mu.enabled - n.mu.RUnlock() - if enabled { - return nil - } - n.mu.Lock() defer n.mu.Unlock() - if n.mu.enabled { + if !n.setEnabled(true) { return nil } - n.mu.enabled = true - - // Create an endpoint to receive broadcast packets on this interface. - if _, ok := n.stack.networkProtocols[header.IPv4ProtocolNumber]; ok { - if _, err := n.addAddressLocked(ipv4BroadcastAddr, NeverPrimaryEndpoint, permanent, static, false /* deprecated */); err != nil { - return err - } - - // As per RFC 1122 section 3.3.7, all hosts should join the all-hosts - // multicast group. Note, the IANA calls the all-hosts multicast group the - // all-systems multicast group. - if err := n.joinGroupLocked(header.IPv4ProtocolNumber, header.IPv4AllSystems); err != nil { - return err - } - } - - // Join the IPv6 All-Nodes Multicast group if the stack is configured to - // use IPv6. This is required to ensure that this node properly receives - // and responds to the various NDP messages that are destined to the - // all-nodes multicast address. An example is the Neighbor Advertisement - // when we perform Duplicate Address Detection, or Router Advertisement - // when we do Router Discovery. See RFC 4862, section 5.4.2 and RFC 4861 - // section 4.2 for more information. - // - // Also auto-generate an IPv6 link-local address based on the NIC's - // link address if it is configured to do so. Note, each interface is - // required to have IPv6 link-local unicast address, as per RFC 4291 - // section 2.1. - _, ok := n.stack.networkProtocols[header.IPv6ProtocolNumber] - if !ok { - return nil - } - - // Join the All-Nodes multicast group before starting DAD as responses to DAD - // (NDP NS) messages may be sent to the All-Nodes multicast group if the - // source address of the NDP NS is the unspecified address, as per RFC 4861 - // section 7.2.4. - if err := n.joinGroupLocked(header.IPv6ProtocolNumber, header.IPv6AllNodesMulticastAddress); err != nil { - return err - } - - // Perform DAD on the all the unicast IPv6 endpoints that are in the permanent - // state. - // - // Addresses may have aleady completed DAD but in the time since the NIC was - // last enabled, other devices may have acquired the same addresses. - for _, r := range n.mu.endpoints { - addr := r.address() - if k := r.getKind(); (k != permanent && k != permanentTentative) || !header.IsV6UnicastAddress(addr) { - continue - } - - r.setKind(permanentTentative) - if err := n.mu.ndp.startDuplicateAddressDetection(addr, r); err != nil { + for _, ep := range n.networkEndpoints { + if err := ep.Enable(); err != nil { return err } } - // Do not auto-generate an IPv6 link-local address for loopback devices. - if n.stack.autoGenIPv6LinkLocal && !n.isLoopback() { - // The valid and preferred lifetime is infinite for the auto-generated - // link-local address. - n.mu.ndp.doSLAAC(header.IPv6LinkLocalPrefix.Subnet(), header.NDPInfiniteLifetime, header.NDPInfiniteLifetime) - } - - // If we are operating as a router, then do not solicit routers since we - // won't process the RAs anyways. - // - // Routers do not process Router Advertisements (RA) the same way a host - // does. That is, routers do not learn from RAs (e.g. on-link prefixes - // and default routers). Therefore, soliciting RAs from other routers on - // a link is unnecessary for routers. - if !n.stack.Forwarding(header.IPv6ProtocolNumber) { - n.mu.ndp.startSolicitingRouters() - } - return nil } -// remove detaches NIC from the link endpoint, and marks existing referenced -// network endpoints expired. This guarantees no packets between this NIC and -// the network stack. +// remove detaches NIC from the link endpoint and releases network endpoint +// resources. This guarantees no packets between this NIC and the network +// stack. func (n *NIC) remove() *tcpip.Error { n.mu.Lock() defer n.mu.Unlock() n.disableLocked() - // TODO(b/151378115): come up with a better way to pick an error than the - // first one. - var err *tcpip.Error - - // Forcefully leave multicast groups. - for nid := range n.mu.mcastJoins { - if tempErr := n.leaveGroupLocked(nid.LocalAddress, true /* force */); tempErr != nil && err == nil { - err = tempErr - } - } - - // Remove permanent and permanentTentative addresses, so no packet goes out. - for nid, ref := range n.mu.endpoints { - switch ref.getKind() { - case permanentTentative, permanent: - if tempErr := n.removePermanentAddressLocked(nid.LocalAddress); tempErr != nil && err == nil { - err = tempErr - } - } - } - - // Release any resources the network endpoint may hold. for _, ep := range n.networkEndpoints { ep.Close() } + n.networkEndpoints = nil // Detach from link endpoint, so no packet comes in. n.linkEP.Attach(nil) - - return err -} - -// becomeIPv6Router transitions n into an IPv6 router. -// -// When transitioning into an IPv6 router, host-only state (NDP discovered -// routers, discovered on-link prefixes, and auto-generated addresses) will -// be cleaned up/invalidated and NDP router solicitations will be stopped. -func (n *NIC) becomeIPv6Router() { - n.mu.Lock() - defer n.mu.Unlock() - - n.mu.ndp.cleanupState(true /* hostOnly */) - n.mu.ndp.stopSolicitingRouters() -} - -// becomeIPv6Host transitions n into an IPv6 host. -// -// When transitioning into an IPv6 host, NDP router solicitations will be -// started. -func (n *NIC) becomeIPv6Host() { - n.mu.Lock() - defer n.mu.Unlock() - - n.mu.ndp.startSolicitingRouters() + return nil } // setPromiscuousMode enables or disables promiscuous mode. @@ -423,7 +232,8 @@ func (n *NIC) isPromiscuousMode() bool { return rv } -func (n *NIC) isLoopback() bool { +// IsLoopback implements NetworkInterface. +func (n *NIC) IsLoopback() bool { return n.linkEP.Capabilities()&CapabilityLoopback != 0 } @@ -440,200 +250,41 @@ func (n *NIC) setSpoofing(enable bool) { // // If an IPv6 primary endpoint is requested, Source Address Selection (as // defined by RFC 6724 section 5) will be performed. -func (n *NIC) primaryEndpoint(protocol tcpip.NetworkProtocolNumber, remoteAddr tcpip.Address) *referencedNetworkEndpoint { - if protocol == header.IPv6ProtocolNumber && len(remoteAddr) != 0 { - return n.primaryIPv6Endpoint(remoteAddr) - } - +func (n *NIC) primaryEndpoint(protocol tcpip.NetworkProtocolNumber, remoteAddr tcpip.Address) AssignableAddressEndpoint { n.mu.RLock() defer n.mu.RUnlock() - var deprecatedEndpoint *referencedNetworkEndpoint - for _, r := range n.mu.primary[protocol] { - if !r.isValidForOutgoingRLocked() { - continue - } - - if !r.deprecated { - if r.tryIncRef() { - // r is not deprecated, so return it immediately. - // - // If we kept track of a deprecated endpoint, decrement its reference - // count since it was incremented when we decided to keep track of it. - if deprecatedEndpoint != nil { - deprecatedEndpoint.decRefLocked() - deprecatedEndpoint = nil - } - - return r - } - } else if deprecatedEndpoint == nil && r.tryIncRef() { - // We prefer an endpoint that is not deprecated, but we keep track of r in - // case n doesn't have any non-deprecated endpoints. - // - // If we end up finding a more preferred endpoint, r's reference count - // will be decremented when such an endpoint is found. - deprecatedEndpoint = r - } - } - - // n doesn't have any valid non-deprecated endpoints, so return - // deprecatedEndpoint (which may be nil if n doesn't have any valid deprecated - // endpoints either). - return deprecatedEndpoint -} - -// ipv6AddrCandidate is an IPv6 candidate for Source Address Selection (RFC -// 6724 section 5). -type ipv6AddrCandidate struct { - ref *referencedNetworkEndpoint - scope header.IPv6AddressScope -} - -// primaryIPv6Endpoint returns an IPv6 endpoint following Source Address -// Selection (RFC 6724 section 5). -// -// Note, only rules 1-3 and 7 are followed. -// -// remoteAddr must be a valid IPv6 address. -func (n *NIC) primaryIPv6Endpoint(remoteAddr tcpip.Address) *referencedNetworkEndpoint { - n.mu.RLock() - ref := n.primaryIPv6EndpointRLocked(remoteAddr) - n.mu.RUnlock() - return ref -} - -// primaryIPv6EndpointLocked returns an IPv6 endpoint following Source Address -// Selection (RFC 6724 section 5). -// -// Note, only rules 1-3 and 7 are followed. -// -// remoteAddr must be a valid IPv6 address. -// -// n.mu MUST be read locked. -func (n *NIC) primaryIPv6EndpointRLocked(remoteAddr tcpip.Address) *referencedNetworkEndpoint { - primaryAddrs := n.mu.primary[header.IPv6ProtocolNumber] - - if len(primaryAddrs) == 0 { - return nil - } - - // Create a candidate set of available addresses we can potentially use as a - // source address. - cs := make([]ipv6AddrCandidate, 0, len(primaryAddrs)) - for _, r := range primaryAddrs { - // If r is not valid for outgoing connections, it is not a valid endpoint. - if !r.isValidForOutgoingRLocked() { - continue - } - - addr := r.address() - scope, err := header.ScopeForIPv6Address(addr) - if err != nil { - // Should never happen as we got r from the primary IPv6 endpoint list and - // ScopeForIPv6Address only returns an error if addr is not an IPv6 - // address. - panic(fmt.Sprintf("header.ScopeForIPv6Address(%s): %s", addr, err)) - } - - cs = append(cs, ipv6AddrCandidate{ - ref: r, - scope: scope, - }) - } - - remoteScope, err := header.ScopeForIPv6Address(remoteAddr) - if err != nil { - // primaryIPv6Endpoint should never be called with an invalid IPv6 address. - panic(fmt.Sprintf("header.ScopeForIPv6Address(%s): %s", remoteAddr, err)) - } - - // Sort the addresses as per RFC 6724 section 5 rules 1-3. - // - // TODO(b/146021396): Implement rules 4-8 of RFC 6724 section 5. - sort.Slice(cs, func(i, j int) bool { - sa := cs[i] - sb := cs[j] - - // Prefer same address as per RFC 6724 section 5 rule 1. - if sa.ref.address() == remoteAddr { - return true - } - if sb.ref.address() == remoteAddr { - return false - } - - // Prefer appropriate scope as per RFC 6724 section 5 rule 2. - if sa.scope < sb.scope { - return sa.scope >= remoteScope - } else if sb.scope < sa.scope { - return sb.scope < remoteScope - } - - // Avoid deprecated addresses as per RFC 6724 section 5 rule 3. - if saDep, sbDep := sa.ref.deprecated, sb.ref.deprecated; saDep != sbDep { - // If sa is not deprecated, it is preferred over sb. - return sbDep - } - - // Prefer temporary addresses as per RFC 6724 section 5 rule 7. - if saTemp, sbTemp := sa.ref.configType == slaacTemp, sb.ref.configType == slaacTemp; saTemp != sbTemp { - return saTemp - } - - // sa and sb are equal, return the endpoint that is closest to the front of - // the primary endpoint list. - return i < j - }) - - // Return the most preferred address that can have its reference count - // incremented. - for _, c := range cs { - if r := c.ref; r.tryIncRef() { - return r - } - } - - return nil -} - -// hasPermanentAddrLocked returns true if n has a permanent (including currently -// tentative) address, addr. -func (n *NIC) hasPermanentAddrLocked(addr tcpip.Address) bool { - ref, ok := n.mu.endpoints[NetworkEndpointID{addr}] - + ep, ok := n.networkEndpoints[protocol] if !ok { - return false + return nil } - kind := ref.getKind() - - return kind == permanent || kind == permanentTentative + return ep.AcquirePrimaryAddress(remoteAddr, n.mu.spoofing) } -type getRefBehaviour int +type getAddressBehaviour int const ( // spoofing indicates that the NIC's spoofing flag should be observed when - // getting a NIC's referenced network endpoint. - spoofing getRefBehaviour = iota + // getting a NIC's address endpoint. + spoofing getAddressBehaviour = iota // promiscuous indicates that the NIC's promiscuous flag should be observed - // when getting a NIC's referenced network endpoint. + // when getting a NIC's address endpoint. promiscuous ) -func (n *NIC) getRef(protocol tcpip.NetworkProtocolNumber, dst tcpip.Address) *referencedNetworkEndpoint { - return n.getRefOrCreateTemp(protocol, dst, CanBePrimaryEndpoint, promiscuous) +func (n *NIC) getAddress(protocol tcpip.NetworkProtocolNumber, dst tcpip.Address) AssignableAddressEndpoint { + return n.getAddressOrCreateTemp(protocol, dst, CanBePrimaryEndpoint, promiscuous) } // findEndpoint finds the endpoint, if any, with the given address. -func (n *NIC) findEndpoint(protocol tcpip.NetworkProtocolNumber, address tcpip.Address, peb PrimaryEndpointBehavior) *referencedNetworkEndpoint { - return n.getRefOrCreateTemp(protocol, address, peb, spoofing) +func (n *NIC) findEndpoint(protocol tcpip.NetworkProtocolNumber, address tcpip.Address, peb PrimaryEndpointBehavior) AssignableAddressEndpoint { + return n.getAddressOrCreateTemp(protocol, address, peb, spoofing) } -// getRefEpOrCreateTemp returns the referenced network endpoint for the given -// protocol and address. +// getAddressEpOrCreateTemp returns the address endpoint for the given protocol +// and address. // // If none exists a temporary one may be created if we are in promiscuous mode // or spoofing. Promiscuous mode will only be checked if promiscuous is true. @@ -641,9 +292,8 @@ func (n *NIC) findEndpoint(protocol tcpip.NetworkProtocolNumber, address tcpip.A // // If the address is the IPv4 broadcast address for an endpoint's network, that // endpoint will be returned. -func (n *NIC) getRefOrCreateTemp(protocol tcpip.NetworkProtocolNumber, address tcpip.Address, peb PrimaryEndpointBehavior, tempRef getRefBehaviour) *referencedNetworkEndpoint { +func (n *NIC) getAddressOrCreateTemp(protocol tcpip.NetworkProtocolNumber, address tcpip.Address, peb PrimaryEndpointBehavior, tempRef getAddressBehaviour) AssignableAddressEndpoint { n.mu.RLock() - var spoofingOrPromiscuous bool switch tempRef { case spoofing: @@ -651,274 +301,54 @@ func (n *NIC) getRefOrCreateTemp(protocol tcpip.NetworkProtocolNumber, address t case promiscuous: spoofingOrPromiscuous = n.mu.promiscuous } - - if ref, ok := n.mu.endpoints[NetworkEndpointID{address}]; ok { - // An endpoint with this id exists, check if it can be used and return it. - if !ref.isAssignedRLocked(spoofingOrPromiscuous) { - n.mu.RUnlock() - return nil - } - - if ref.tryIncRef() { - n.mu.RUnlock() - return ref - } - } - - if protocol == header.IPv4ProtocolNumber { - if ref := n.getIPv4RefForBroadcastOrLoopbackRLocked(address); ref != nil { - n.mu.RUnlock() - return ref - } - } n.mu.RUnlock() - - if !spoofingOrPromiscuous { - return nil - } - - // Try again with the lock in exclusive mode. If we still can't get the - // endpoint, create a new "temporary" endpoint. It will only exist while - // there's a route through it. - n.mu.Lock() - ref := n.getRefOrCreateTempLocked(protocol, address, peb) - n.mu.Unlock() - return ref + return n.getAddressOrCreateTempInner(protocol, address, spoofingOrPromiscuous, peb) } -// getRefForBroadcastOrLoopbackRLocked returns an endpoint whose address is the -// broadcast address for the endpoint's network or an address in the endpoint's -// subnet if the NIC is a loopback interface. This matches linux behaviour. -// -// n.mu MUST be read or write locked. -func (n *NIC) getIPv4RefForBroadcastOrLoopbackRLocked(address tcpip.Address) *referencedNetworkEndpoint { - for _, ref := range n.mu.endpoints { - // Only IPv4 has a notion of broadcast addresses or considers the loopback - // interface bound to an address's whole subnet (on linux). - if ref.protocol != header.IPv4ProtocolNumber { - continue - } - - subnet := ref.addrWithPrefix().Subnet() - if (subnet.IsBroadcast(address) || (n.isLoopback() && subnet.Contains(address))) && ref.isValidForOutgoingRLocked() && ref.tryIncRef() { - return ref - } +// getAddressOrCreateTempInner is like getAddressEpOrCreateTemp except a boolean +// is passed to indicate whether or not we should generate temporary endpoints. +func (n *NIC) getAddressOrCreateTempInner(protocol tcpip.NetworkProtocolNumber, address tcpip.Address, createTemp bool, peb PrimaryEndpointBehavior) AssignableAddressEndpoint { + if ep, ok := n.networkEndpoints[protocol]; ok { + return ep.AcquireAssignedAddress(address, createTemp, peb) } return nil } -/// getRefOrCreateTempLocked returns an existing endpoint for address or creates -/// and returns a temporary endpoint. -// -// If the address is the IPv4 broadcast address for an endpoint's network, that -// endpoint will be returned. -// -// n.mu must be write locked. -func (n *NIC) getRefOrCreateTempLocked(protocol tcpip.NetworkProtocolNumber, address tcpip.Address, peb PrimaryEndpointBehavior) *referencedNetworkEndpoint { - if ref, ok := n.mu.endpoints[NetworkEndpointID{address}]; ok { - // No need to check the type as we are ok with expired endpoints at this - // point. - if ref.tryIncRef() { - return ref - } - // tryIncRef failing means the endpoint is scheduled to be removed once the - // lock is released. Remove it here so we can create a new (temporary) one. - // The removal logic waiting for the lock handles this case. - n.removeEndpointLocked(ref) - } - - if protocol == header.IPv4ProtocolNumber { - if ref := n.getIPv4RefForBroadcastOrLoopbackRLocked(address); ref != nil { - return ref - } - } - - // Add a new temporary endpoint. - netProto, ok := n.stack.networkProtocols[protocol] - if !ok { - return nil - } - ref, _ := n.addAddressLocked(tcpip.ProtocolAddress{ - Protocol: protocol, - AddressWithPrefix: tcpip.AddressWithPrefix{ - Address: address, - PrefixLen: netProto.DefaultPrefixLen(), - }, - }, peb, temporary, static, false) - return ref -} - -// addAddressLocked adds a new protocolAddress to n. -// -// If n already has the address in a non-permanent state, and the kind given is -// permanent, that address will be promoted in place and its properties set to -// the properties provided. Otherwise, it returns tcpip.ErrDuplicateAddress. -func (n *NIC) addAddressLocked(protocolAddress tcpip.ProtocolAddress, peb PrimaryEndpointBehavior, kind networkEndpointKind, configType networkEndpointConfigType, deprecated bool) (*referencedNetworkEndpoint, *tcpip.Error) { - // TODO(b/141022673): Validate IP addresses before adding them. - - // Sanity check. - id := NetworkEndpointID{LocalAddress: protocolAddress.AddressWithPrefix.Address} - if ref, ok := n.mu.endpoints[id]; ok { - // Endpoint already exists. - if kind != permanent { - return nil, tcpip.ErrDuplicateAddress - } - switch ref.getKind() { - case permanentTentative, permanent: - // The NIC already have a permanent endpoint with that address. - return nil, tcpip.ErrDuplicateAddress - case permanentExpired, temporary: - // Promote the endpoint to become permanent and respect the new peb, - // configType and deprecated status. - if ref.tryIncRef() { - // TODO(b/147748385): Perform Duplicate Address Detection when promoting - // an IPv6 endpoint to permanent. - ref.setKind(permanent) - ref.deprecated = deprecated - ref.configType = configType - - refs := n.mu.primary[ref.protocol] - for i, r := range refs { - if r == ref { - switch peb { - case CanBePrimaryEndpoint: - return ref, nil - case FirstPrimaryEndpoint: - if i == 0 { - return ref, nil - } - n.mu.primary[r.protocol] = append(refs[:i], refs[i+1:]...) - case NeverPrimaryEndpoint: - n.mu.primary[r.protocol] = append(refs[:i], refs[i+1:]...) - return ref, nil - } - } - } - - n.insertPrimaryEndpointLocked(ref, peb) - - return ref, nil - } - // tryIncRef failing means the endpoint is scheduled to be removed once - // the lock is released. Remove it here so we can create a new - // (permanent) one. The removal logic waiting for the lock handles this - // case. - n.removeEndpointLocked(ref) - } - } - +// addAddress adds a new address to n, so that it starts accepting packets +// targeted at the given address (and network protocol). +func (n *NIC) addAddress(protocolAddress tcpip.ProtocolAddress, peb PrimaryEndpointBehavior) *tcpip.Error { ep, ok := n.networkEndpoints[protocolAddress.Protocol] if !ok { - return nil, tcpip.ErrUnknownProtocol - } - - isIPv6Unicast := protocolAddress.Protocol == header.IPv6ProtocolNumber && header.IsV6UnicastAddress(protocolAddress.AddressWithPrefix.Address) - - // If the address is an IPv6 address and it is a permanent address, - // mark it as tentative so it goes through the DAD process if the NIC is - // enabled. If the NIC is not enabled, DAD will be started when the NIC is - // enabled. - if isIPv6Unicast && kind == permanent { - kind = permanentTentative + return tcpip.ErrUnknownProtocol } - ref := &referencedNetworkEndpoint{ - refs: 1, - addr: protocolAddress.AddressWithPrefix, - ep: ep, - nic: n, - protocol: protocolAddress.Protocol, - kind: kind, - configType: configType, - deprecated: deprecated, + addressEndpoint, err := ep.AddAndAcquirePermanentAddress(protocolAddress.AddressWithPrefix, peb, AddressConfigStatic, false /* deprecated */) + if err == nil { + // We have no need for the address endpoint. + addressEndpoint.DecRef() } - - // Set up resolver if link address resolution exists for this protocol. - if n.linkEP.Capabilities()&CapabilityResolutionRequired != 0 { - if linkRes, ok := n.stack.linkAddrResolvers[protocolAddress.Protocol]; ok { - ref.linkCache = n.stack - ref.linkRes = linkRes - } - } - - // If we are adding an IPv6 unicast address, join the solicited-node - // multicast address. - if isIPv6Unicast { - snmc := header.SolicitedNodeAddr(protocolAddress.AddressWithPrefix.Address) - if err := n.joinGroupLocked(protocolAddress.Protocol, snmc); err != nil { - return nil, err - } - } - - n.mu.endpoints[id] = ref - - n.insertPrimaryEndpointLocked(ref, peb) - - // If we are adding a tentative IPv6 address, start DAD if the NIC is enabled. - if isIPv6Unicast && kind == permanentTentative && n.mu.enabled { - if err := n.mu.ndp.startDuplicateAddressDetection(protocolAddress.AddressWithPrefix.Address, ref); err != nil { - return nil, err - } - } - - return ref, nil -} - -// AddAddress adds a new address to n, so that it starts accepting packets -// targeted at the given address (and network protocol). -func (n *NIC) AddAddress(protocolAddress tcpip.ProtocolAddress, peb PrimaryEndpointBehavior) *tcpip.Error { - // Add the endpoint. - n.mu.Lock() - _, err := n.addAddressLocked(protocolAddress, peb, permanent, static, false /* deprecated */) - n.mu.Unlock() - return err } -// AllAddresses returns all addresses (primary and non-primary) associated with +// allPermanentAddresses returns all permanent addresses associated with // this NIC. -func (n *NIC) AllAddresses() []tcpip.ProtocolAddress { - n.mu.RLock() - defer n.mu.RUnlock() - - addrs := make([]tcpip.ProtocolAddress, 0, len(n.mu.endpoints)) - for _, ref := range n.mu.endpoints { - // Don't include tentative, expired or temporary endpoints to - // avoid confusion and prevent the caller from using those. - switch ref.getKind() { - case permanentExpired, temporary: - continue +func (n *NIC) allPermanentAddresses() []tcpip.ProtocolAddress { + var addrs []tcpip.ProtocolAddress + for p, ep := range n.networkEndpoints { + for _, a := range ep.PermanentAddresses() { + addrs = append(addrs, tcpip.ProtocolAddress{Protocol: p, AddressWithPrefix: a}) } - - addrs = append(addrs, tcpip.ProtocolAddress{ - Protocol: ref.protocol, - AddressWithPrefix: ref.addrWithPrefix(), - }) } return addrs } -// PrimaryAddresses returns the primary addresses associated with this NIC. -func (n *NIC) PrimaryAddresses() []tcpip.ProtocolAddress { - n.mu.RLock() - defer n.mu.RUnlock() - +// primaryAddresses returns the primary addresses associated with this NIC. +func (n *NIC) primaryAddresses() []tcpip.ProtocolAddress { var addrs []tcpip.ProtocolAddress - for proto, list := range n.mu.primary { - for _, ref := range list { - // Don't include tentative, expired or tempory endpoints - // to avoid confusion and prevent the caller from using - // those. - switch ref.getKind() { - case permanentTentative, permanentExpired, temporary: - continue - } - - addrs = append(addrs, tcpip.ProtocolAddress{ - Protocol: proto, - AddressWithPrefix: ref.addrWithPrefix(), - }) + for p, ep := range n.networkEndpoints { + for _, a := range ep.PrimaryAddresses() { + addrs = append(addrs, tcpip.ProtocolAddress{Protocol: p, AddressWithPrefix: a}) } } return addrs @@ -930,147 +360,26 @@ func (n *NIC) PrimaryAddresses() []tcpip.ProtocolAddress { // address exists. If no non-deprecated address exists, the first deprecated // address will be returned. func (n *NIC) primaryAddress(proto tcpip.NetworkProtocolNumber) tcpip.AddressWithPrefix { - n.mu.RLock() - defer n.mu.RUnlock() - - list, ok := n.mu.primary[proto] - if !ok { + addressEndpoint := n.primaryEndpoint(proto, "") + if addressEndpoint == nil { return tcpip.AddressWithPrefix{} } - - var deprecatedEndpoint *referencedNetworkEndpoint - for _, ref := range list { - // Don't include tentative, expired or tempory endpoints to avoid confusion - // and prevent the caller from using those. - switch ref.getKind() { - case permanentTentative, permanentExpired, temporary: - continue - } - - if !ref.deprecated { - return ref.addrWithPrefix() - } - - if deprecatedEndpoint == nil { - deprecatedEndpoint = ref - } - } - - if deprecatedEndpoint != nil { - return deprecatedEndpoint.addrWithPrefix() - } - - return tcpip.AddressWithPrefix{} -} - -// insertPrimaryEndpointLocked adds r to n's primary endpoint list as required -// by peb. -// -// n MUST be locked. -func (n *NIC) insertPrimaryEndpointLocked(r *referencedNetworkEndpoint, peb PrimaryEndpointBehavior) { - switch peb { - case CanBePrimaryEndpoint: - n.mu.primary[r.protocol] = append(n.mu.primary[r.protocol], r) - case FirstPrimaryEndpoint: - n.mu.primary[r.protocol] = append([]*referencedNetworkEndpoint{r}, n.mu.primary[r.protocol]...) - } -} - -func (n *NIC) removeEndpointLocked(r *referencedNetworkEndpoint) { - id := NetworkEndpointID{LocalAddress: r.address()} - - // Nothing to do if the reference has already been replaced with a different - // one. This happens in the case where 1) this endpoint's ref count hit zero - // and was waiting (on the lock) to be removed and 2) the same address was - // re-added in the meantime by removing this endpoint from the list and - // adding a new one. - if n.mu.endpoints[id] != r { - return - } - - if r.getKind() == permanent { - panic("Reference count dropped to zero before being removed") - } - - delete(n.mu.endpoints, id) - refs := n.mu.primary[r.protocol] - for i, ref := range refs { - if ref == r { - n.mu.primary[r.protocol] = append(refs[:i], refs[i+1:]...) - refs[len(refs)-1] = nil - break - } - } -} - -func (n *NIC) removeEndpoint(r *referencedNetworkEndpoint) { - n.mu.Lock() - n.removeEndpointLocked(r) - n.mu.Unlock() -} - -func (n *NIC) removePermanentAddressLocked(addr tcpip.Address) *tcpip.Error { - r, ok := n.mu.endpoints[NetworkEndpointID{addr}] - if !ok { - return tcpip.ErrBadLocalAddress - } - - kind := r.getKind() - if kind != permanent && kind != permanentTentative { - return tcpip.ErrBadLocalAddress - } - - switch r.protocol { - case header.IPv6ProtocolNumber: - return n.removePermanentIPv6EndpointLocked(r, true /* allowSLAACInvalidation */) - default: - r.expireLocked() - return nil - } + addr := addressEndpoint.AddressWithPrefix() + addressEndpoint.DecRef() + return addr } -func (n *NIC) removePermanentIPv6EndpointLocked(r *referencedNetworkEndpoint, allowSLAACInvalidation bool) *tcpip.Error { - addr := r.addrWithPrefix() - - isIPv6Unicast := header.IsV6UnicastAddress(addr.Address) - - if isIPv6Unicast { - n.mu.ndp.stopDuplicateAddressDetection(addr.Address) - - // If we are removing an address generated via SLAAC, cleanup - // its SLAAC resources and notify the integrator. - switch r.configType { - case slaac: - n.mu.ndp.cleanupSLAACAddrResourcesAndNotify(addr, allowSLAACInvalidation) - case slaacTemp: - n.mu.ndp.cleanupTempSLAACAddrResourcesAndNotify(addr, allowSLAACInvalidation) - } - } - - r.expireLocked() - - // At this point the endpoint is deleted. - - // If we are removing an IPv6 unicast address, leave the solicited-node - // multicast address. - // - // We ignore the tcpip.ErrBadLocalAddress error because the solicited-node - // multicast group may be left by user action. - if isIPv6Unicast { - snmc := header.SolicitedNodeAddr(addr.Address) - if err := n.leaveGroupLocked(snmc, false /* force */); err != nil && err != tcpip.ErrBadLocalAddress { +// removeAddress removes an address from n. +func (n *NIC) removeAddress(addr tcpip.Address) *tcpip.Error { + for _, ep := range n.networkEndpoints { + if err := ep.RemovePermanentAddress(addr); err == tcpip.ErrBadLocalAddress { + continue + } else { return err } } - return nil -} - -// RemoveAddress removes an address from n. -func (n *NIC) RemoveAddress(addr tcpip.Address) *tcpip.Error { - n.mu.Lock() - defer n.mu.Unlock() - return n.removePermanentAddressLocked(addr) + return tcpip.ErrBadLocalAddress } func (n *NIC) neighbors() ([]NeighborEntry, *tcpip.Error) { @@ -1121,91 +430,66 @@ func (n *NIC) clearNeighbors() *tcpip.Error { // joinGroup adds a new endpoint for the given multicast address, if none // exists yet. Otherwise it just increments its count. func (n *NIC) joinGroup(protocol tcpip.NetworkProtocolNumber, addr tcpip.Address) *tcpip.Error { - n.mu.Lock() - defer n.mu.Unlock() - - return n.joinGroupLocked(protocol, addr) -} - -// joinGroupLocked adds a new endpoint for the given multicast address, if none -// exists yet. Otherwise it just increments its count. n MUST be locked before -// joinGroupLocked is called. -func (n *NIC) joinGroupLocked(protocol tcpip.NetworkProtocolNumber, addr tcpip.Address) *tcpip.Error { // TODO(b/143102137): When implementing MLD, make sure MLD packets are // not sent unless a valid link-local address is available for use on n // as an MLD packet's source address must be a link-local address as // outlined in RFC 3810 section 5. - id := NetworkEndpointID{addr} - joins := n.mu.mcastJoins[id] - if joins == 0 { - netProto, ok := n.stack.networkProtocols[protocol] - if !ok { - return tcpip.ErrUnknownProtocol - } - if _, err := n.addAddressLocked(tcpip.ProtocolAddress{ - Protocol: protocol, - AddressWithPrefix: tcpip.AddressWithPrefix{ - Address: addr, - PrefixLen: netProto.DefaultPrefixLen(), - }, - }, NeverPrimaryEndpoint, permanent, static, false /* deprecated */); err != nil { - return err - } + ep, ok := n.networkEndpoints[protocol] + if !ok { + return tcpip.ErrNotSupported } - n.mu.mcastJoins[id] = joins + 1 - return nil + + gep, ok := ep.(GroupAddressableEndpoint) + if !ok { + return tcpip.ErrNotSupported + } + + _, err := gep.JoinGroup(addr) + return err } // leaveGroup decrements the count for the given multicast address, and when it // reaches zero removes the endpoint for this address. -func (n *NIC) leaveGroup(addr tcpip.Address) *tcpip.Error { - n.mu.Lock() - defer n.mu.Unlock() - - return n.leaveGroupLocked(addr, false /* force */) -} +func (n *NIC) leaveGroup(protocol tcpip.NetworkProtocolNumber, addr tcpip.Address) *tcpip.Error { + ep, ok := n.networkEndpoints[protocol] + if !ok { + return tcpip.ErrNotSupported + } -// leaveGroupLocked decrements the count for the given multicast address, and -// when it reaches zero removes the endpoint for this address. n MUST be locked -// before leaveGroupLocked is called. -// -// If force is true, then the count for the multicast addres is ignored and the -// endpoint will be removed immediately. -func (n *NIC) leaveGroupLocked(addr tcpip.Address, force bool) *tcpip.Error { - id := NetworkEndpointID{addr} - joins, ok := n.mu.mcastJoins[id] + gep, ok := ep.(GroupAddressableEndpoint) if !ok { - // There are no joins with this address on this NIC. - return tcpip.ErrBadLocalAddress + return tcpip.ErrNotSupported } - joins-- - if force || joins == 0 { - // There are no outstanding joins or we are forced to leave, clean up. - delete(n.mu.mcastJoins, id) - return n.removePermanentAddressLocked(addr) + if _, err := gep.LeaveGroup(addr); err != nil { + return err } - n.mu.mcastJoins[id] = joins return nil } // isInGroup returns true if n has joined the multicast group addr. func (n *NIC) isInGroup(addr tcpip.Address) bool { - n.mu.RLock() - joins := n.mu.mcastJoins[NetworkEndpointID{addr}] - n.mu.RUnlock() + for _, ep := range n.networkEndpoints { + gep, ok := ep.(GroupAddressableEndpoint) + if !ok { + continue + } + + if gep.IsInGroup(addr) { + return true + } + } - return joins != 0 + return false } -func handlePacket(protocol tcpip.NetworkProtocolNumber, dst, src tcpip.Address, localLinkAddr, remotelinkAddr tcpip.LinkAddress, ref *referencedNetworkEndpoint, pkt *PacketBuffer) { - r := makeRoute(protocol, dst, src, localLinkAddr, ref, false /* handleLocal */, false /* multicastLoop */) +func (n *NIC) handlePacket(protocol tcpip.NetworkProtocolNumber, dst, src tcpip.Address, remotelinkAddr tcpip.LinkAddress, addressEndpoint AssignableAddressEndpoint, pkt *PacketBuffer) { + r := makeRoute(protocol, dst, src, n, addressEndpoint, false /* handleLocal */, false /* multicastLoop */) r.RemoteLinkAddress = remotelinkAddr - - ref.ep.HandlePacket(&r, pkt) - ref.decRef() + addressEndpoint.NetworkEndpoint().HandlePacket(&r, pkt) + addressEndpoint.DecRef() } // DeliverNetworkPacket finds the appropriate network protocol endpoint and @@ -1216,7 +500,7 @@ func handlePacket(protocol tcpip.NetworkProtocolNumber, dst, src tcpip.Address, // the ownership of the items is not retained by the caller. func (n *NIC) DeliverNetworkPacket(remote, local tcpip.LinkAddress, protocol tcpip.NetworkProtocolNumber, pkt *PacketBuffer) { n.mu.RLock() - enabled := n.mu.enabled + enabled := n.Enabled() // If the NIC is not yet enabled, don't receive any packets. if !enabled { n.mu.RUnlock() @@ -1274,17 +558,21 @@ func (n *NIC) DeliverNetworkPacket(remote, local tcpip.LinkAddress, protocol tcp src, dst := netProto.ParseAddresses(pkt.NetworkHeader().View()) - if n.stack.handleLocal && !n.isLoopback() && n.getRef(protocol, src) != nil { - // The source address is one of our own, so we never should have gotten a - // packet like this unless handleLocal is false. Loopback also calls this - // function even though the packets didn't come from the physical interface - // so don't drop those. - n.stack.stats.IP.InvalidSourceAddressesReceived.Increment() - return + if n.stack.handleLocal && !n.IsLoopback() { + if r := n.getAddress(protocol, src); r != nil { + r.DecRef() + + // The source address is one of our own, so we never should have gotten a + // packet like this unless handleLocal is false. Loopback also calls this + // function even though the packets didn't come from the physical interface + // so don't drop those. + n.stack.stats.IP.InvalidSourceAddressesReceived.Increment() + return + } } // Loopback traffic skips the prerouting chain. - if !n.isLoopback() { + if !n.IsLoopback() { // iptables filtering. ipt := n.stack.IPTables() address := n.primaryAddress(protocol) @@ -1295,8 +583,8 @@ func (n *NIC) DeliverNetworkPacket(remote, local tcpip.LinkAddress, protocol tcp } } - if ref := n.getRef(protocol, dst); ref != nil { - handlePacket(protocol, dst, src, n.linkEP.LinkAddress(), remote, ref, pkt) + if addressEndpoint := n.getAddress(protocol, dst); addressEndpoint != nil { + n.handlePacket(protocol, dst, src, remote, addressEndpoint, pkt) return } @@ -1312,20 +600,20 @@ func (n *NIC) DeliverNetworkPacket(remote, local tcpip.LinkAddress, protocol tcp } // Found a NIC. - n := r.ref.nic - n.mu.RLock() - ref, ok := n.mu.endpoints[NetworkEndpointID{dst}] - ok = ok && ref.isValidForOutgoingRLocked() && ref.tryIncRef() - n.mu.RUnlock() - if ok { - r.LocalLinkAddress = n.linkEP.LinkAddress() - r.RemoteLinkAddress = remote - r.RemoteAddress = src - // TODO(b/123449044): Update the source NIC as well. - ref.ep.HandlePacket(&r, pkt) - ref.decRef() - r.Release() - return + n := r.nic + if addressEndpoint := n.getAddressOrCreateTempInner(protocol, dst, false, NeverPrimaryEndpoint); addressEndpoint != nil { + if n.isValidForOutgoing(addressEndpoint) { + r.LocalLinkAddress = n.linkEP.LinkAddress() + r.RemoteLinkAddress = remote + r.RemoteAddress = src + // TODO(b/123449044): Update the source NIC as well. + addressEndpoint.NetworkEndpoint().HandlePacket(&r, pkt) + addressEndpoint.DecRef() + r.Release() + return + } + + addressEndpoint.DecRef() } // n doesn't have a destination endpoint. @@ -1498,96 +786,23 @@ func (n *NIC) DeliverTransportControlPacket(local, remote tcpip.Address, net tcp } } -// ID returns the identifier of n. +// ID implements NetworkInterface. func (n *NIC) ID() tcpip.NICID { return n.id } -// Name returns the name of n. +// Name implements NetworkInterface. func (n *NIC) Name() string { return n.name } -// Stack returns the instance of the Stack that owns this NIC. -func (n *NIC) Stack() *Stack { - return n.stack -} - // LinkEndpoint returns the link endpoint of n. func (n *NIC) LinkEndpoint() LinkEndpoint { return n.linkEP } -// isAddrTentative returns true if addr is tentative on n. -// -// Note that if addr is not associated with n, then this function will return -// false. It will only return true if the address is associated with the NIC -// AND it is tentative. -func (n *NIC) isAddrTentative(addr tcpip.Address) bool { - n.mu.RLock() - defer n.mu.RUnlock() - - ref, ok := n.mu.endpoints[NetworkEndpointID{addr}] - if !ok { - return false - } - - return ref.getKind() == permanentTentative -} - -// dupTentativeAddrDetected attempts to inform n that a tentative addr is a -// duplicate on a link. -// -// dupTentativeAddrDetected will remove the tentative address if it exists. If -// the address was generated via SLAAC, an attempt will be made to generate a -// new address. -func (n *NIC) dupTentativeAddrDetected(addr tcpip.Address) *tcpip.Error { - n.mu.Lock() - defer n.mu.Unlock() - - ref, ok := n.mu.endpoints[NetworkEndpointID{addr}] - if !ok { - return tcpip.ErrBadAddress - } - - if ref.getKind() != permanentTentative { - return tcpip.ErrInvalidEndpointState - } - - // If the address is a SLAAC address, do not invalidate its SLAAC prefix as a - // new address will be generated for it. - if err := n.removePermanentIPv6EndpointLocked(ref, false /* allowSLAACInvalidation */); err != nil { - return err - } - - prefix := ref.addrWithPrefix().Subnet() - - switch ref.configType { - case slaac: - n.mu.ndp.regenerateSLAACAddr(prefix) - case slaacTemp: - // Do not reset the generation attempts counter for the prefix as the - // temporary address is being regenerated in response to a DAD conflict. - n.mu.ndp.regenerateTempSLAACAddr(prefix, false /* resetGenAttempts */) - } - - return nil -} - -// setNDPConfigs sets the NDP configurations for n. -// -// Note, if c contains invalid NDP configuration values, it will be fixed to -// use default values for the erroneous values. -func (n *NIC) setNDPConfigs(c NDPConfigurations) { - c.validate() - - n.mu.Lock() - n.mu.ndp.configs = c - n.mu.Unlock() -} - -// NUDConfigs gets the NUD configurations for n. -func (n *NIC) NUDConfigs() (NUDConfigurations, *tcpip.Error) { +// nudConfigs gets the NUD configurations for n. +func (n *NIC) nudConfigs() (NUDConfigurations, *tcpip.Error) { if n.neigh == nil { return NUDConfigurations{}, tcpip.ErrNotSupported } @@ -1607,49 +822,6 @@ func (n *NIC) setNUDConfigs(c NUDConfigurations) *tcpip.Error { return nil } -// handleNDPRA handles an NDP Router Advertisement message that arrived on n. -func (n *NIC) handleNDPRA(ip tcpip.Address, ra header.NDPRouterAdvert) { - n.mu.Lock() - defer n.mu.Unlock() - - n.mu.ndp.handleRA(ip, ra) -} - -type networkEndpointKind int32 - -const ( - // A permanentTentative endpoint is a permanent address that is not yet - // considered to be fully bound to an interface in the traditional - // sense. That is, the address is associated with a NIC, but packets - // destined to the address MUST NOT be accepted and MUST be silently - // dropped, and the address MUST NOT be used as a source address for - // outgoing packets. For IPv6, addresses will be of this kind until - // NDP's Duplicate Address Detection has resolved, or be deleted if - // the process results in detecting a duplicate address. - permanentTentative networkEndpointKind = iota - - // A permanent endpoint is created by adding a permanent address (vs. a - // temporary one) to the NIC. Its reference count is biased by 1 to avoid - // removal when no route holds a reference to it. It is removed by explicitly - // removing the permanent address from the NIC. - permanent - - // An expired permanent endpoint is a permanent endpoint that had its address - // removed from the NIC, and it is waiting to be removed once no more routes - // hold a reference to it. This is achieved by decreasing its reference count - // by 1. If its address is re-added before the endpoint is removed, its type - // changes back to permanent and its reference count increases by 1 again. - permanentExpired - - // A temporary endpoint is created for spoofing outgoing packets, or when in - // promiscuous mode and accepting incoming packets that don't match any - // permanent endpoint. Its reference count is not biased by 1 and the - // endpoint is removed immediately when no more route holds a reference to - // it. A temporary endpoint can be promoted to permanent if its address - // is added permanently. - temporary -) - func (n *NIC) registerPacketEndpoint(netProto tcpip.NetworkProtocolNumber, ep PacketEndpoint) *tcpip.Error { n.mu.Lock() defer n.mu.Unlock() @@ -1680,153 +852,12 @@ func (n *NIC) unregisterPacketEndpoint(netProto tcpip.NetworkProtocolNumber, ep } } -type networkEndpointConfigType int32 - -const ( - // A statically configured endpoint is an address that was added by - // some user-specified action (adding an explicit address, joining a - // multicast group). - static networkEndpointConfigType = iota - - // A SLAAC configured endpoint is an IPv6 endpoint that was added by - // SLAAC as per RFC 4862 section 5.5.3. - slaac - - // A temporary SLAAC configured endpoint is an IPv6 endpoint that was added by - // SLAAC as per RFC 4941. Temporary SLAAC addresses are short-lived and are - // not expected to be valid (or preferred) forever; hence the term temporary. - slaacTemp -) - -type referencedNetworkEndpoint struct { - ep NetworkEndpoint - addr tcpip.AddressWithPrefix - nic *NIC - protocol tcpip.NetworkProtocolNumber - - // linkCache is set if link address resolution is enabled for this - // protocol. Set to nil otherwise. - linkCache LinkAddressCache - - // linkRes is set if link address resolution is enabled for this protocol. - // Set to nil otherwise. - linkRes LinkAddressResolver - - // refs is counting references held for this endpoint. When refs hits zero it - // triggers the automatic removal of the endpoint from the NIC. - refs int32 - - // networkEndpointKind must only be accessed using {get,set}Kind(). - kind networkEndpointKind - - // configType is the method that was used to configure this endpoint. - // This must never change except during endpoint creation and promotion to - // permanent. - configType networkEndpointConfigType - - // deprecated indicates whether or not the endpoint should be considered - // deprecated. That is, when deprecated is true, other endpoints that are not - // deprecated should be preferred. - deprecated bool -} - -func (r *referencedNetworkEndpoint) address() tcpip.Address { - return r.addr.Address -} - -func (r *referencedNetworkEndpoint) addrWithPrefix() tcpip.AddressWithPrefix { - return r.addr -} - -func (r *referencedNetworkEndpoint) getKind() networkEndpointKind { - return networkEndpointKind(atomic.LoadInt32((*int32)(&r.kind))) -} - -func (r *referencedNetworkEndpoint) setKind(kind networkEndpointKind) { - atomic.StoreInt32((*int32)(&r.kind), int32(kind)) -} - // isValidForOutgoing returns true if the endpoint can be used to send out a // packet. It requires the endpoint to not be marked expired (i.e., its address) // has been removed) unless the NIC is in spoofing mode, or temporary. -func (r *referencedNetworkEndpoint) isValidForOutgoing() bool { - r.nic.mu.RLock() - defer r.nic.mu.RUnlock() - - return r.isValidForOutgoingRLocked() -} - -// isValidForOutgoingRLocked is the same as isValidForOutgoing but requires -// r.nic.mu to be read locked. -func (r *referencedNetworkEndpoint) isValidForOutgoingRLocked() bool { - if !r.nic.mu.enabled { - return false - } - - return r.isAssignedRLocked(r.nic.mu.spoofing) -} - -// isAssignedRLocked returns true if r is considered to be assigned to the NIC. -// -// r.nic.mu must be read locked. -func (r *referencedNetworkEndpoint) isAssignedRLocked(spoofingOrPromiscuous bool) bool { - switch r.getKind() { - case permanentTentative: - return false - case permanentExpired: - return spoofingOrPromiscuous - default: - return true - } -} - -// expireLocked decrements the reference count and marks the permanent endpoint -// as expired. -func (r *referencedNetworkEndpoint) expireLocked() { - r.setKind(permanentExpired) - r.decRefLocked() -} - -// decRef decrements the ref count and cleans up the endpoint once it reaches -// zero. -func (r *referencedNetworkEndpoint) decRef() { - if atomic.AddInt32(&r.refs, -1) == 0 { - r.nic.removeEndpoint(r) - } -} - -// decRefLocked is the same as decRef but assumes that the NIC.mu mutex is -// locked. -func (r *referencedNetworkEndpoint) decRefLocked() { - if atomic.AddInt32(&r.refs, -1) == 0 { - r.nic.removeEndpointLocked(r) - } -} - -// incRef increments the ref count. It must only be called when the caller is -// known to be holding a reference to the endpoint, otherwise tryIncRef should -// be used. -func (r *referencedNetworkEndpoint) incRef() { - atomic.AddInt32(&r.refs, 1) -} - -// tryIncRef attempts to increment the ref count from n to n+1, but only if n is -// not zero. That is, it will increment the count if the endpoint is still -// alive, and do nothing if it has already been clean up. -func (r *referencedNetworkEndpoint) tryIncRef() bool { - for { - v := atomic.LoadInt32(&r.refs) - if v == 0 { - return false - } - - if atomic.CompareAndSwapInt32(&r.refs, v, v+1) { - return true - } - } -} - -// stack returns the Stack instance that owns the underlying endpoint. -func (r *referencedNetworkEndpoint) stack() *Stack { - return r.nic.stack +func (n *NIC) isValidForOutgoing(ep AssignableAddressEndpoint) bool { + n.mu.RLock() + spoofing := n.mu.spoofing + n.mu.RUnlock() + return n.Enabled() && ep.IsAssigned(spoofing) } diff --git a/pkg/tcpip/stack/registration.go b/pkg/tcpip/stack/registration.go index 780a5ebde..ef42fd6e1 100644 --- a/pkg/tcpip/stack/registration.go +++ b/pkg/tcpip/stack/registration.go @@ -15,6 +15,8 @@ package stack import ( + "fmt" + "gvisor.dev/gvisor/pkg/sleep" "gvisor.dev/gvisor/pkg/tcpip" "gvisor.dev/gvisor/pkg/tcpip/buffer" @@ -259,9 +261,251 @@ type NetworkHeaderParams struct { TOS uint8 } +// GroupAddressableEndpoint is an endpoint that supports group addressing. +// +// An endpoint is considered to support group addressing when one or more +// endpoints may associate themselves with the same identifier (group address). +type GroupAddressableEndpoint interface { + // JoinGroup joins the spcified group. + // + // Returns true if the group was newly joined. + JoinGroup(group tcpip.Address) (bool, *tcpip.Error) + + // LeaveGroup attempts to leave the specified group. + // + // Returns tcpip.ErrBadLocalAddress if the endpoint has not joined the group. + LeaveGroup(group tcpip.Address) (bool, *tcpip.Error) + + // IsInGroup returns true if the endpoint is a member of the specified group. + IsInGroup(group tcpip.Address) bool +} + +// PrimaryEndpointBehavior is an enumeration of an AddressEndpoint's primary +// behavior. +type PrimaryEndpointBehavior int + +const ( + // CanBePrimaryEndpoint indicates the endpoint can be used as a primary + // endpoint for new connections with no local address. This is the + // default when calling NIC.AddAddress. + CanBePrimaryEndpoint PrimaryEndpointBehavior = iota + + // FirstPrimaryEndpoint indicates the endpoint should be the first + // primary endpoint considered. If there are multiple endpoints with + // this behavior, they are ordered by recency. + FirstPrimaryEndpoint + + // NeverPrimaryEndpoint indicates the endpoint should never be a + // primary endpoint. + NeverPrimaryEndpoint +) + +// AddressConfigType is the method used to add an address. +type AddressConfigType int + +const ( + // AddressConfigStatic is a statically configured address endpoint that was + // added by some user-specified action (adding an explicit address, joining a + // multicast group). + AddressConfigStatic AddressConfigType = iota + + // AddressConfigSlaac is an address endpoint added by SLAAC, as per RFC 4862 + // section 5.5.3. + AddressConfigSlaac + + // AddressConfigSlaacTemp is a temporary address endpoint added by SLAAC as + // per RFC 4941. Temporary SLAAC addresses are short-lived and are not + // to be valid (or preferred) forever; hence the term temporary. + AddressConfigSlaacTemp +) + +// AssignableAddressEndpoint is a reference counted address endpoint that may be +// assigned to a NetworkEndpoint. +type AssignableAddressEndpoint interface { + // NetworkEndpoint returns the NetworkEndpoint the receiver is associated + // with. + NetworkEndpoint() NetworkEndpoint + + // AddressWithPrefix returns the endpoint's address. + AddressWithPrefix() tcpip.AddressWithPrefix + + // IsAssigned returns whether or not the endpoint is considered bound + // to its NetworkEndpoint. + IsAssigned(allowExpired bool) bool + + // IncRef increments this endpoint's reference count. + // + // Returns true if it was successfully incremented. If it returns false, then + // the endpoint is considered expired and should no longer be used. + IncRef() bool + + // DecRef decrements this endpoint's reference count. + DecRef() +} + +// AddressEndpoint is an endpoint representing an address assigned to an +// AddressableEndpoint. +type AddressEndpoint interface { + AssignableAddressEndpoint + + // GetKind returns the address kind for this endpoint. + GetKind() AddressKind + + // SetKind sets the address kind for this endpoint. + SetKind(AddressKind) + + // ConfigType returns the method used to add the address. + ConfigType() AddressConfigType + + // Deprecated returns whether or not this endpoint is deprecated. + Deprecated() bool + + // SetDeprecated sets this endpoint's deprecated status. + SetDeprecated(bool) +} + +// AddressKind is the kind of of an address. +// +// See the values of AddressKind for more details. +type AddressKind int + +const ( + // PermanentTentative is a permanent address endpoint that is not yet + // considered to be fully bound to an interface in the traditional + // sense. That is, the address is associated with a NIC, but packets + // destined to the address MUST NOT be accepted and MUST be silently + // dropped, and the address MUST NOT be used as a source address for + // outgoing packets. For IPv6, addresses are of this kind until NDP's + // Duplicate Address Detection (DAD) resolves. If DAD fails, the address + // is removed. + PermanentTentative AddressKind = iota + + // Permanent is a permanent endpoint (vs. a temporary one) assigned to the + // NIC. Its reference count is biased by 1 to avoid removal when no route + // holds a reference to it. It is removed by explicitly removing the address + // from the NIC. + Permanent + + // PermanentExpired is a permanent endpoint that had its address removed from + // the NIC, and it is waiting to be removed once no references to it are held. + // + // If the address is re-added before the endpoint is removed, its type + // changes back to Permanent. + PermanentExpired + + // Temporary is an endpoint, created on a one-off basis to temporarily + // consider the NIC bound an an address that it is not explictiy bound to + // (such as a permanent address). Its reference count must not be biased by 1 + // so that the address is removed immediately when references to it are no + // longer held. + // + // A temporary endpoint may be promoted to permanent if the address is added + // permanently. + Temporary +) + +// IsPermanent returns true if the AddressKind represents a permanent address. +func (k AddressKind) IsPermanent() bool { + switch k { + case Permanent, PermanentTentative: + return true + case Temporary, PermanentExpired: + return false + default: + panic(fmt.Sprintf("unrecognized address kind = %d", k)) + } +} + +// AddressableEndpoint is an endpoint that supports addressing. +// +// An endpoint is considered to support addressing when the endpoint may +// associate itself with an identifier (address). +type AddressableEndpoint interface { + // AddAndAcquirePermanentAddress adds the passed permanent address. + // + // Returns tcpip.ErrDuplicateAddress if the address exists. + // + // Acquires and returns the AddressEndpoint for the added address. + AddAndAcquirePermanentAddress(addr tcpip.AddressWithPrefix, peb PrimaryEndpointBehavior, configType AddressConfigType, deprecated bool) (AddressEndpoint, *tcpip.Error) + + // RemovePermanentAddress removes the passed address if it is a permanent + // address. + // + // Returns tcpip.ErrBadLocalAddress if the endpoint does not have the passed + // permanent address. + RemovePermanentAddress(addr tcpip.Address) *tcpip.Error + + // AcquireAssignedAddress returns an AddressEndpoint for the passed address + // that is considered bound to the endpoint, optionally creating a temporary + // endpoint if requested and no existing address exists. + // + // The returned endpoint's reference count is incremented. + // + // Returns nil if the specified address is not local to this endpoint. + AcquireAssignedAddress(localAddr tcpip.Address, allowTemp bool, tempPEB PrimaryEndpointBehavior) AddressEndpoint + + // AcquirePrimaryAddress returns a primary endpoint to use when communicating + // with the passed remote address. + // + // If allowExpired is true, expired addresses may be returned. + // + // The returned endpoint's reference count is incremented. + // + // Returns nil if a primary endpoint is not available. + AcquirePrimaryAddress(remoteAddr tcpip.Address, allowExpired bool) AddressEndpoint + + // PrimaryAddresses returns the primary addresses. + PrimaryAddresses() []tcpip.AddressWithPrefix + + // PermanentAddresses returns all the permanent addresses. + PermanentAddresses() []tcpip.AddressWithPrefix +} + +// NDPEndpoint is a network endpoint that supports NDP. +type NDPEndpoint interface { + NetworkEndpoint + + // InvalidateDefaultRouter invalidates a default router discovered through + // NDP. + InvalidateDefaultRouter(tcpip.Address) +} + +// NetworkInterface is a network interface. +type NetworkInterface interface { + // ID returns the interface's ID. + ID() tcpip.NICID + + // IsLoopback returns true if the interface is a loopback interface. + IsLoopback() bool + + // Name returns the name of the interface. + // + // May return an empty string if the interface is not configured with a name. + Name() string + + // Enabled returns true if the interface is enabled. + Enabled() bool +} + // NetworkEndpoint is the interface that needs to be implemented by endpoints // of network layer protocols (e.g., ipv4, ipv6). type NetworkEndpoint interface { + AddressableEndpoint + + // Enable enables the endpoint. + // + // Must only be called when the stack is in a state that allows the endpoint + // to send and receive packets. + // + // Returns tcpip.ErrNotPermitted if the endpoint cannot be enabled. + Enable() *tcpip.Error + + // Enabled returns true if the endpoint is enabled. + Enabled() bool + + // Disable disables the endpoint. + Disable() + // DefaultTTL is the default time-to-live value (or hop limit, in ipv6) // for this endpoint. DefaultTTL() uint8 @@ -312,6 +556,17 @@ type NetworkEndpoint interface { NetworkProtocolNumber() tcpip.NetworkProtocolNumber } +// ForwardingNetworkProtocol is a NetworkProtocol that may forward packets. +type ForwardingNetworkProtocol interface { + NetworkProtocol + + // Forwarding returns the forwarding configuration. + Forwarding() bool + + // SetForwarding sets the forwarding configuration. + SetForwarding(bool) +} + // NetworkProtocol is the interface that needs to be implemented by network // protocols (e.g., ipv4, ipv6) that want to be part of the networking stack. type NetworkProtocol interface { @@ -331,7 +586,7 @@ type NetworkProtocol interface { ParseAddresses(v buffer.View) (src, dst tcpip.Address) // NewEndpoint creates a new endpoint of this protocol. - NewEndpoint(nicID tcpip.NICID, linkAddrCache LinkAddressCache, nud NUDHandler, dispatcher TransportDispatcher, sender LinkEndpoint, st *Stack) NetworkEndpoint + NewEndpoint(nic NetworkInterface, linkAddrCache LinkAddressCache, nud NUDHandler, dispatcher TransportDispatcher, sender LinkEndpoint, st *Stack) NetworkEndpoint // SetOption allows enabling/disabling protocol specific features. // SetOption returns an error if the option is not supported or the @@ -460,8 +715,8 @@ type LinkEndpoint interface { // Attach attaches the data link layer endpoint to the network-layer // dispatcher of the stack. // - // Attach will be called with a nil dispatcher if the receiver's associated - // NIC is being removed. + // Attach is called with a nil dispatcher when the endpoint's NIC is being + // removed. Attach(dispatcher NetworkDispatcher) // IsAttached returns whether a NetworkDispatcher is attached to the diff --git a/pkg/tcpip/stack/route.go b/pkg/tcpip/stack/route.go index 2cbbf0de8..1b008a067 100644 --- a/pkg/tcpip/stack/route.go +++ b/pkg/tcpip/stack/route.go @@ -42,17 +42,27 @@ type Route struct { // NetProto is the network-layer protocol. NetProto tcpip.NetworkProtocolNumber - // ref a reference to the network endpoint through which the route - // starts. - ref *referencedNetworkEndpoint - // Loop controls where WritePacket should send packets. Loop PacketLooping + + // nic is the NIC the route goes through. + nic *NIC + + // addressEndpoint is the local address this route is associated with. + addressEndpoint AssignableAddressEndpoint + + // linkCache is set if link address resolution is enabled for this protocol on + // the route's NIC. + linkCache LinkAddressCache + + // linkRes is set if link address resolution is enabled for this protocol on + // the route's NIC. + linkRes LinkAddressResolver } // makeRoute initializes a new route. It takes ownership of the provided -// reference to a network endpoint. -func makeRoute(netProto tcpip.NetworkProtocolNumber, localAddr, remoteAddr tcpip.Address, localLinkAddr tcpip.LinkAddress, ref *referencedNetworkEndpoint, handleLocal, multicastLoop bool) Route { +// AssignableAddressEndpoint. +func makeRoute(netProto tcpip.NetworkProtocolNumber, localAddr, remoteAddr tcpip.Address, nic *NIC, addressEndpoint AssignableAddressEndpoint, handleLocal, multicastLoop bool) Route { loop := PacketOut if handleLocal && localAddr != "" && remoteAddr == localAddr { loop = PacketLoop @@ -62,29 +72,39 @@ func makeRoute(netProto tcpip.NetworkProtocolNumber, localAddr, remoteAddr tcpip loop |= PacketLoop } - return Route{ + r := Route{ NetProto: netProto, LocalAddress: localAddr, - LocalLinkAddress: localLinkAddr, + LocalLinkAddress: nic.linkEP.LinkAddress(), RemoteAddress: remoteAddr, - ref: ref, + addressEndpoint: addressEndpoint, + nic: nic, Loop: loop, } + + if nic := r.nic; nic.linkEP.Capabilities()&CapabilityResolutionRequired != 0 { + if linkRes, ok := nic.stack.linkAddrResolvers[r.NetProto]; ok { + r.linkRes = linkRes + r.linkCache = nic.stack + } + } + + return r } // NICID returns the id of the NIC from which this route originates. func (r *Route) NICID() tcpip.NICID { - return r.ref.ep.NICID() + return r.addressEndpoint.NetworkEndpoint().NICID() } // MaxHeaderLength forwards the call to the network endpoint's implementation. func (r *Route) MaxHeaderLength() uint16 { - return r.ref.ep.MaxHeaderLength() + return r.addressEndpoint.NetworkEndpoint().MaxHeaderLength() } // Stats returns a mutable copy of current stats. func (r *Route) Stats() tcpip.Stats { - return r.ref.nic.stack.Stats() + return r.nic.stack.Stats() } // PseudoHeaderChecksum forwards the call to the network endpoint's @@ -95,12 +115,12 @@ func (r *Route) PseudoHeaderChecksum(protocol tcpip.TransportProtocolNumber, tot // Capabilities returns the link-layer capabilities of the route. func (r *Route) Capabilities() LinkEndpointCapabilities { - return r.ref.ep.Capabilities() + return r.addressEndpoint.NetworkEndpoint().Capabilities() } // GSOMaxSize returns the maximum GSO packet size. func (r *Route) GSOMaxSize() uint32 { - if gso, ok := r.ref.ep.(GSOEndpoint); ok { + if gso, ok := r.addressEndpoint.NetworkEndpoint().(GSOEndpoint); ok { return gso.GSOMaxSize() } return 0 @@ -138,8 +158,8 @@ func (r *Route) Resolve(waker *sleep.Waker) (<-chan struct{}, *tcpip.Error) { nextAddr = r.RemoteAddress } - if r.ref.nic.neigh != nil { - entry, ch, err := r.ref.nic.neigh.entry(nextAddr, r.LocalAddress, r.ref.linkRes, waker) + if neigh := r.nic.neigh; neigh != nil { + entry, ch, err := neigh.entry(nextAddr, r.LocalAddress, r.linkRes, waker) if err != nil { return ch, err } @@ -147,7 +167,7 @@ func (r *Route) Resolve(waker *sleep.Waker) (<-chan struct{}, *tcpip.Error) { return nil, nil } - linkAddr, ch, err := r.ref.linkCache.GetLinkAddress(r.ref.nic.ID(), nextAddr, r.LocalAddress, r.NetProto, waker) + linkAddr, ch, err := r.linkCache.GetLinkAddress(r.nic.ID(), nextAddr, r.LocalAddress, r.NetProto, waker) if err != nil { return ch, err } @@ -162,12 +182,12 @@ func (r *Route) RemoveWaker(waker *sleep.Waker) { nextAddr = r.RemoteAddress } - if r.ref.nic.neigh != nil { - r.ref.nic.neigh.removeWaker(nextAddr, waker) + if neigh := r.nic.neigh; neigh != nil { + neigh.removeWaker(nextAddr, waker) return } - r.ref.linkCache.RemoveWaker(r.ref.nic.ID(), nextAddr, waker) + r.linkCache.RemoveWaker(r.nic.ID(), nextAddr, waker) } // IsResolutionRequired returns true if Resolve() must be called to resolve @@ -175,27 +195,27 @@ func (r *Route) RemoveWaker(waker *sleep.Waker) { // // The NIC r uses must not be locked. func (r *Route) IsResolutionRequired() bool { - if r.ref.nic.neigh != nil { - return r.ref.isValidForOutgoing() && r.ref.linkRes != nil && r.RemoteLinkAddress == "" + if r.nic.neigh != nil { + return r.nic.isValidForOutgoing(r.addressEndpoint) && r.linkRes != nil && r.RemoteLinkAddress == "" } - return r.ref.isValidForOutgoing() && r.ref.linkCache != nil && r.RemoteLinkAddress == "" + return r.nic.isValidForOutgoing(r.addressEndpoint) && r.linkCache != nil && r.RemoteLinkAddress == "" } // WritePacket writes the packet through the given route. func (r *Route) WritePacket(gso *GSO, params NetworkHeaderParams, pkt *PacketBuffer) *tcpip.Error { - if !r.ref.isValidForOutgoing() { + if !r.nic.isValidForOutgoing(r.addressEndpoint) { return tcpip.ErrInvalidEndpointState } // WritePacket takes ownership of pkt, calculate numBytes first. numBytes := pkt.Size() - err := r.ref.ep.WritePacket(r, gso, params, pkt) + err := r.addressEndpoint.NetworkEndpoint().WritePacket(r, gso, params, pkt) if err != nil { r.Stats().IP.OutgoingPacketErrors.Increment() } else { - r.ref.nic.stats.Tx.Packets.Increment() - r.ref.nic.stats.Tx.Bytes.IncrementBy(uint64(numBytes)) + r.nic.stats.Tx.Packets.Increment() + r.nic.stats.Tx.Bytes.IncrementBy(uint64(numBytes)) } return err } @@ -203,76 +223,75 @@ func (r *Route) WritePacket(gso *GSO, params NetworkHeaderParams, pkt *PacketBuf // WritePackets writes a list of n packets through the given route and returns // the number of packets written. func (r *Route) WritePackets(gso *GSO, pkts PacketBufferList, params NetworkHeaderParams) (int, *tcpip.Error) { - if !r.ref.isValidForOutgoing() { + if !r.nic.isValidForOutgoing(r.addressEndpoint) { return 0, tcpip.ErrInvalidEndpointState } // WritePackets takes ownership of pkt, calculate length first. numPkts := pkts.Len() - n, err := r.ref.ep.WritePackets(r, gso, pkts, params) + n, err := r.addressEndpoint.NetworkEndpoint().WritePackets(r, gso, pkts, params) if err != nil { r.Stats().IP.OutgoingPacketErrors.IncrementBy(uint64(numPkts - n)) } - r.ref.nic.stats.Tx.Packets.IncrementBy(uint64(n)) + r.nic.stats.Tx.Packets.IncrementBy(uint64(n)) writtenBytes := 0 for i, pb := 0, pkts.Front(); i < n && pb != nil; i, pb = i+1, pb.Next() { writtenBytes += pb.Size() } - r.ref.nic.stats.Tx.Bytes.IncrementBy(uint64(writtenBytes)) + r.nic.stats.Tx.Bytes.IncrementBy(uint64(writtenBytes)) return n, err } // WriteHeaderIncludedPacket writes a packet already containing a network // header through the given route. func (r *Route) WriteHeaderIncludedPacket(pkt *PacketBuffer) *tcpip.Error { - if !r.ref.isValidForOutgoing() { + if !r.nic.isValidForOutgoing(r.addressEndpoint) { return tcpip.ErrInvalidEndpointState } // WriteHeaderIncludedPacket takes ownership of pkt, calculate numBytes first. numBytes := pkt.Data.Size() - if err := r.ref.ep.WriteHeaderIncludedPacket(r, pkt); err != nil { + if err := r.addressEndpoint.NetworkEndpoint().WriteHeaderIncludedPacket(r, pkt); err != nil { r.Stats().IP.OutgoingPacketErrors.Increment() return err } - r.ref.nic.stats.Tx.Packets.Increment() - r.ref.nic.stats.Tx.Bytes.IncrementBy(uint64(numBytes)) + r.nic.stats.Tx.Packets.Increment() + r.nic.stats.Tx.Bytes.IncrementBy(uint64(numBytes)) return nil } // DefaultTTL returns the default TTL of the underlying network endpoint. func (r *Route) DefaultTTL() uint8 { - return r.ref.ep.DefaultTTL() + return r.addressEndpoint.NetworkEndpoint().DefaultTTL() } // MTU returns the MTU of the underlying network endpoint. func (r *Route) MTU() uint32 { - return r.ref.ep.MTU() + return r.addressEndpoint.NetworkEndpoint().MTU() } // NetworkProtocolNumber returns the NetworkProtocolNumber of the underlying // network endpoint. func (r *Route) NetworkProtocolNumber() tcpip.NetworkProtocolNumber { - return r.ref.ep.NetworkProtocolNumber() + return r.addressEndpoint.NetworkEndpoint().NetworkProtocolNumber() } // Release frees all resources associated with the route. func (r *Route) Release() { - if r.ref != nil { - r.ref.decRef() - r.ref = nil + if r.addressEndpoint != nil { + r.addressEndpoint.DecRef() + r.addressEndpoint = nil } } -// Clone Clone a route such that the original one can be released and the new -// one will remain valid. +// Clone clones the route. func (r *Route) Clone() Route { - if r.ref != nil { - r.ref.incRef() + if r.addressEndpoint != nil { + _ = r.addressEndpoint.IncRef() } return *r } @@ -296,7 +315,7 @@ func (r *Route) MakeLoopedRoute() Route { // Stack returns the instance of the Stack that owns this route. func (r *Route) Stack() *Stack { - return r.ref.stack() + return r.nic.stack } func (r *Route) isV4Broadcast(addr tcpip.Address) bool { @@ -304,7 +323,7 @@ func (r *Route) isV4Broadcast(addr tcpip.Address) bool { return true } - subnet := r.ref.addrWithPrefix().Subnet() + subnet := r.addressEndpoint.AddressWithPrefix().Subnet() return subnet.IsBroadcast(addr) } @@ -330,7 +349,10 @@ func (r *Route) ReverseRoute(src tcpip.Address, dst tcpip.Address) Route { LocalLinkAddress: r.RemoteLinkAddress, RemoteAddress: src, RemoteLinkAddress: r.LocalLinkAddress, - ref: r.ref, Loop: r.Loop, + addressEndpoint: r.addressEndpoint, + nic: r.nic, + linkCache: r.linkCache, + linkRes: r.linkRes, } } diff --git a/pkg/tcpip/stack/stack.go b/pkg/tcpip/stack/stack.go index c22633f6b..b740aa305 100644 --- a/pkg/tcpip/stack/stack.go +++ b/pkg/tcpip/stack/stack.go @@ -363,38 +363,6 @@ func (u *uniqueIDGenerator) UniqueID() uint64 { return atomic.AddUint64((*uint64)(u), 1) } -// NICNameFromID is a function that returns a stable name for the specified NIC, -// even if different NIC IDs are used to refer to the same NIC in different -// program runs. It is used when generating opaque interface identifiers (IIDs). -// If the NIC was created with a name, it will be passed to NICNameFromID. -// -// NICNameFromID SHOULD return unique NIC names so unique opaque IIDs are -// generated for the same prefix on differnt NICs. -type NICNameFromID func(tcpip.NICID, string) string - -// OpaqueInterfaceIdentifierOptions holds the options related to the generation -// of opaque interface indentifiers (IIDs) as defined by RFC 7217. -type OpaqueInterfaceIdentifierOptions struct { - // NICNameFromID is a function that returns a stable name for a specified NIC, - // even if the NIC ID changes over time. - // - // Must be specified to generate the opaque IID. - NICNameFromID NICNameFromID - - // SecretKey is a pseudo-random number used as the secret key when generating - // opaque IIDs as defined by RFC 7217. The key SHOULD be at least - // header.OpaqueIIDSecretKeyMinBytes bytes and MUST follow minimum randomness - // requirements for security as outlined by RFC 4086. SecretKey MUST NOT - // change between program runs, unless explicitly changed. - // - // OpaqueInterfaceIdentifierOptions takes ownership of SecretKey. SecretKey - // MUST NOT be modified after Stack is created. - // - // May be nil, but a nil value is highly discouraged to maintain - // some level of randomness between nodes. - SecretKey []byte -} - // Stack is a networking stack, with all supported protocols, NICs, and route // table. type Stack struct { @@ -402,13 +370,6 @@ type Stack struct { networkProtocols map[tcpip.NetworkProtocolNumber]NetworkProtocol linkAddrResolvers map[tcpip.NetworkProtocolNumber]LinkAddressResolver - // forwarding contains the whether packet forwarding is enabled or not for - // different network protocols. - forwarding struct { - sync.RWMutex - protocols map[tcpip.NetworkProtocolNumber]bool - } - // rawFactory creates raw endpoints. If nil, raw endpoints are // disabled. It is set during Stack creation and is immutable. rawFactory RawFactory @@ -461,9 +422,6 @@ type Stack struct { // TODO(gvisor.dev/issue/940): S/R this field. seed uint32 - // ndpConfigs is the default NDP configurations used by interfaces. - ndpConfigs NDPConfigurations - // nudConfigs is the default NUD configurations used by interfaces. nudConfigs NUDConfigurations @@ -471,15 +429,6 @@ type Stack struct { // by the NIC's neighborCache instead of linkAddrCache. useNeighborCache bool - // autoGenIPv6LinkLocal determines whether or not the stack will attempt - // to auto-generate an IPv6 link-local address for newly enabled non-loopback - // NICs. See the AutoGenIPv6LinkLocal field of Options for more details. - autoGenIPv6LinkLocal bool - - // ndpDisp is the NDP event dispatcher that is used to send the netstack - // integrator NDP related events. - ndpDisp NDPDispatcher - // nudDisp is the NUD event dispatcher that is used to send the netstack // integrator NUD related events. nudDisp NUDDispatcher @@ -487,14 +436,6 @@ type Stack struct { // uniqueIDGenerator is a generator of unique identifiers. uniqueIDGenerator UniqueID - // opaqueIIDOpts hold the options for generating opaque interface identifiers - // (IIDs) as outlined by RFC 7217. - opaqueIIDOpts OpaqueInterfaceIdentifierOptions - - // tempIIDSeed is used to seed the initial temporary interface identifier - // history value used to generate IIDs for temporary SLAAC addresses. - tempIIDSeed []byte - // forwarder holds the packets that wait for their link-address resolutions // to complete, and forwards them when each resolution is done. forwarder *forwardQueue @@ -553,13 +494,6 @@ type Options struct { // 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 - // DupAddrDetectTransmits field, implying that DAD will not be performed - // before assigning an address to a NIC. - NDPConfigs NDPConfigurations - // NUDConfigs is the default NUD configurations used by interfaces. NUDConfigs NUDConfigurations @@ -570,24 +504,6 @@ type Options struct { // and ClearNeighbors. UseNeighborCache bool - // AutoGenIPv6LinkLocal determines whether or not the stack will attempt to - // auto-generate an IPv6 link-local address for newly enabled non-loopback - // NICs. - // - // Note, setting this to true does not mean that a link-local address - // will be assigned right away, or at all. If Duplicate Address Detection - // is enabled, an address will only be assigned if it successfully resolves. - // If it fails, no further attempt will be made to auto-generate an IPv6 - // link-local address. - // - // The generated link-local address will follow RFC 4291 Appendix A - // guidelines. - AutoGenIPv6LinkLocal bool - - // NDPDisp is the NDP event dispatcher that an integrator can provide to - // receive NDP related events. - NDPDisp NDPDispatcher - // NUDDisp is the NUD event dispatcher that an integrator can provide to // receive NUD related events. NUDDisp NUDDispatcher @@ -596,31 +512,12 @@ type Options struct { // this is non-nil. RawFactory RawFactory - // OpaqueIIDOpts hold the options for generating opaque interface - // identifiers (IIDs) as outlined by RFC 7217. - OpaqueIIDOpts OpaqueInterfaceIdentifierOptions - // RandSource is an optional source to use to generate random // numbers. If omitted it defaults to a Source seeded by the data // returned by rand.Read(). // // RandSource must be thread-safe. RandSource mathrand.Source - - // TempIIDSeed is used to seed the initial temporary interface identifier - // history value used to generate IIDs for temporary SLAAC addresses. - // - // Temporary SLAAC adresses are short-lived addresses which are unpredictable - // and random from the perspective of other nodes on the network. It is - // recommended that the seed be a random byte buffer of at least - // header.IIDSize bytes to make sure that temporary SLAAC addresses are - // sufficiently random. It should follow minimum randomness requirements for - // security as outlined by RFC 4086. - // - // Note: using a nil value, the same seed across netstack program runs, or a - // seed that is too small would reduce randomness and increase predictability, - // defeating the purpose of temporary SLAAC addresses. - TempIIDSeed []byte } // TransportEndpointInfo holds useful information about a transport endpoint @@ -723,36 +620,28 @@ func New(opts Options) *Stack { randSrc = &lockedRandomSource{src: mathrand.NewSource(generateRandInt64())} } - // Make sure opts.NDPConfigs contains valid values only. - opts.NDPConfigs.validate() - opts.NUDConfigs.resetInvalidFields() s := &Stack{ - transportProtocols: make(map[tcpip.TransportProtocolNumber]*transportProtocolState), - networkProtocols: make(map[tcpip.NetworkProtocolNumber]NetworkProtocol), - linkAddrResolvers: make(map[tcpip.NetworkProtocolNumber]LinkAddressResolver), - nics: make(map[tcpip.NICID]*NIC), - cleanupEndpoints: make(map[TransportEndpoint]struct{}), - linkAddrCache: newLinkAddrCache(ageLimit, resolutionTimeout, resolutionAttempts), - PortManager: ports.NewPortManager(), - clock: clock, - stats: opts.Stats.FillIn(), - handleLocal: opts.HandleLocal, - tables: DefaultTables(), - icmpRateLimiter: NewICMPRateLimiter(), - seed: generateRandUint32(), - ndpConfigs: opts.NDPConfigs, - nudConfigs: opts.NUDConfigs, - useNeighborCache: opts.UseNeighborCache, - autoGenIPv6LinkLocal: opts.AutoGenIPv6LinkLocal, - uniqueIDGenerator: opts.UniqueID, - ndpDisp: opts.NDPDisp, - nudDisp: opts.NUDDisp, - opaqueIIDOpts: opts.OpaqueIIDOpts, - tempIIDSeed: opts.TempIIDSeed, - forwarder: newForwardQueue(), - randomGenerator: mathrand.New(randSrc), + transportProtocols: make(map[tcpip.TransportProtocolNumber]*transportProtocolState), + networkProtocols: make(map[tcpip.NetworkProtocolNumber]NetworkProtocol), + linkAddrResolvers: make(map[tcpip.NetworkProtocolNumber]LinkAddressResolver), + nics: make(map[tcpip.NICID]*NIC), + cleanupEndpoints: make(map[TransportEndpoint]struct{}), + linkAddrCache: newLinkAddrCache(ageLimit, resolutionTimeout, resolutionAttempts), + PortManager: ports.NewPortManager(), + clock: clock, + stats: opts.Stats.FillIn(), + handleLocal: opts.HandleLocal, + tables: DefaultTables(), + icmpRateLimiter: NewICMPRateLimiter(), + seed: generateRandUint32(), + nudConfigs: opts.NUDConfigs, + useNeighborCache: opts.UseNeighborCache, + uniqueIDGenerator: opts.UniqueID, + nudDisp: opts.NUDDisp, + forwarder: newForwardQueue(), + randomGenerator: mathrand.New(randSrc), sendBufferSize: SendBufferSizeOption{ Min: MinBufferSize, Default: DefaultBufferSize, @@ -764,7 +653,6 @@ func New(opts Options) *Stack { Max: DefaultMaxBufferSize, }, } - s.forwarding.protocols = make(map[tcpip.NetworkProtocolNumber]bool) // Add specified network protocols. for _, netProtoFactory := range opts.NetworkProtocols { @@ -884,42 +772,37 @@ func (s *Stack) Stats() tcpip.Stats { return s.stats } -// SetForwarding enables or disables packet forwarding between NICs. -func (s *Stack) SetForwarding(protocol tcpip.NetworkProtocolNumber, enable bool) { - s.forwarding.Lock() - defer s.forwarding.Unlock() - - // If this stack does not support the protocol, do nothing. - if _, ok := s.networkProtocols[protocol]; !ok { - return +// SetForwarding enables or disables packet forwarding between NICs for the +// passed protocol. +func (s *Stack) SetForwarding(protocolNum tcpip.NetworkProtocolNumber, enable bool) *tcpip.Error { + protocol, ok := s.networkProtocols[protocolNum] + if !ok { + return tcpip.ErrUnknownProtocol } - // If the forwarding value for this protocol hasn't changed then do - // nothing. - if forwarding := s.forwarding.protocols[protocol]; forwarding == enable { - return + forwardingProtocol, ok := protocol.(ForwardingNetworkProtocol) + if !ok { + return tcpip.ErrNotSupported } - s.forwarding.protocols[protocol] = enable + forwardingProtocol.SetForwarding(enable) + return nil +} - if protocol == header.IPv6ProtocolNumber { - if enable { - for _, nic := range s.nics { - nic.becomeIPv6Router() - } - } else { - for _, nic := range s.nics { - nic.becomeIPv6Host() - } - } +// Forwarding returns true if packet forwarding between NICs is enabled for the +// passed protocol. +func (s *Stack) Forwarding(protocolNum tcpip.NetworkProtocolNumber) bool { + protocol, ok := s.networkProtocols[protocolNum] + if !ok { + return false } -} -// Forwarding returns if packet forwarding between NICs is enabled. -func (s *Stack) Forwarding(protocol tcpip.NetworkProtocolNumber) bool { - s.forwarding.RLock() - defer s.forwarding.RUnlock() - return s.forwarding.protocols[protocol] + forwardingProtocol, ok := protocol.(ForwardingNetworkProtocol) + if !ok { + return false + } + + return forwardingProtocol.Forwarding() } // SetRouteTable assigns the route table to be used by this stack. It @@ -1081,7 +964,8 @@ func (s *Stack) DisableNIC(id tcpip.NICID) *tcpip.Error { return tcpip.ErrUnknownNICID } - return nic.disable() + nic.disable() + return nil } // CheckNIC checks if a NIC is usable. @@ -1094,7 +978,7 @@ func (s *Stack) CheckNIC(id tcpip.NICID) bool { return false } - return nic.enabled() + return nic.Enabled() } // RemoveNIC removes NIC and all related routes from the network stack. @@ -1172,14 +1056,14 @@ func (s *Stack) NICInfo() map[tcpip.NICID]NICInfo { for id, nic := range s.nics { flags := NICStateFlags{ Up: true, // Netstack interfaces are always up. - Running: nic.enabled(), + Running: nic.Enabled(), Promiscuous: nic.isPromiscuousMode(), - Loopback: nic.isLoopback(), + Loopback: nic.IsLoopback(), } nics[id] = NICInfo{ Name: nic.name, LinkAddress: nic.linkEP.LinkAddress(), - ProtocolAddresses: nic.PrimaryAddresses(), + ProtocolAddresses: nic.primaryAddresses(), Flags: flags, MTU: nic.linkEP.MTU(), Stats: nic.stats, @@ -1243,7 +1127,7 @@ func (s *Stack) AddProtocolAddressWithOptions(id tcpip.NICID, protocolAddress tc return tcpip.ErrUnknownNICID } - return nic.AddAddress(protocolAddress, peb) + return nic.addAddress(protocolAddress, peb) } // RemoveAddress removes an existing network-layer address from the specified @@ -1253,7 +1137,7 @@ func (s *Stack) RemoveAddress(id tcpip.NICID, addr tcpip.Address) *tcpip.Error { defer s.mu.RUnlock() if nic, ok := s.nics[id]; ok { - return nic.RemoveAddress(addr) + return nic.removeAddress(addr) } return tcpip.ErrUnknownNICID @@ -1267,7 +1151,7 @@ func (s *Stack) AllAddresses() map[tcpip.NICID][]tcpip.ProtocolAddress { nics := make(map[tcpip.NICID][]tcpip.ProtocolAddress) for id, nic := range s.nics { - nics[id] = nic.AllAddresses() + nics[id] = nic.allPermanentAddresses() } return nics } @@ -1289,7 +1173,7 @@ func (s *Stack) GetMainNICAddress(id tcpip.NICID, protocol tcpip.NetworkProtocol return nic.primaryAddress(protocol), nil } -func (s *Stack) getRefEP(nic *NIC, localAddr, remoteAddr tcpip.Address, netProto tcpip.NetworkProtocolNumber) (ref *referencedNetworkEndpoint) { +func (s *Stack) getAddressEP(nic *NIC, localAddr, remoteAddr tcpip.Address, netProto tcpip.NetworkProtocolNumber) AssignableAddressEndpoint { if len(localAddr) == 0 { return nic.primaryEndpoint(netProto, remoteAddr) } @@ -1306,9 +1190,9 @@ func (s *Stack) FindRoute(id tcpip.NICID, localAddr, remoteAddr tcpip.Address, n isMulticast := header.IsV4MulticastAddress(remoteAddr) || header.IsV6MulticastAddress(remoteAddr) needRoute := !(isLocalBroadcast || isMulticast || header.IsV6LinkLocalAddress(remoteAddr)) if id != 0 && !needRoute { - if nic, ok := s.nics[id]; ok && nic.enabled() { - if ref := s.getRefEP(nic, localAddr, remoteAddr, netProto); ref != nil { - return makeRoute(netProto, ref.address(), remoteAddr, nic.linkEP.LinkAddress(), ref, s.handleLocal && !nic.isLoopback(), multicastLoop && !nic.isLoopback()), nil + if nic, ok := s.nics[id]; ok && nic.Enabled() { + if addressEndpoint := s.getAddressEP(nic, localAddr, remoteAddr, netProto); addressEndpoint != nil { + return makeRoute(netProto, addressEndpoint.AddressWithPrefix().Address, remoteAddr, nic, addressEndpoint, s.handleLocal && !nic.IsLoopback(), multicastLoop && !nic.IsLoopback()), nil } } } else { @@ -1316,20 +1200,20 @@ func (s *Stack) FindRoute(id tcpip.NICID, localAddr, remoteAddr tcpip.Address, n if (id != 0 && id != route.NIC) || (len(remoteAddr) != 0 && !route.Destination.Contains(remoteAddr)) { continue } - if nic, ok := s.nics[route.NIC]; ok && nic.enabled() { - if ref := s.getRefEP(nic, localAddr, remoteAddr, netProto); ref != nil { + if nic, ok := s.nics[route.NIC]; ok && nic.Enabled() { + if addressEndpoint := s.getAddressEP(nic, localAddr, remoteAddr, netProto); addressEndpoint != nil { if len(remoteAddr) == 0 { // If no remote address was provided, then the route // provided will refer to the link local address. - remoteAddr = ref.address() + remoteAddr = addressEndpoint.AddressWithPrefix().Address } - r := makeRoute(netProto, ref.address(), remoteAddr, nic.linkEP.LinkAddress(), ref, s.handleLocal && !nic.isLoopback(), multicastLoop && !nic.isLoopback()) + r := makeRoute(netProto, addressEndpoint.AddressWithPrefix().Address, remoteAddr, nic, addressEndpoint, s.handleLocal && !nic.IsLoopback(), multicastLoop && !nic.IsLoopback()) if len(route.Gateway) > 0 { if needRoute { r.NextHop = route.Gateway } - } else if subnet := ref.addrWithPrefix().Subnet(); subnet.IsBroadcast(remoteAddr) { + } else if subnet := addressEndpoint.AddressWithPrefix().Subnet(); subnet.IsBroadcast(remoteAddr) { r.RemoteLinkAddress = header.EthernetBroadcastAddress } @@ -1367,21 +1251,20 @@ func (s *Stack) CheckLocalAddress(nicID tcpip.NICID, protocol tcpip.NetworkProto return 0 } - ref := nic.findEndpoint(protocol, addr, CanBePrimaryEndpoint) - if ref == nil { + addressEndpoint := nic.findEndpoint(protocol, addr, CanBePrimaryEndpoint) + if addressEndpoint == nil { return 0 } - ref.decRef() + addressEndpoint.DecRef() return nic.id } // Go through all the NICs. for _, nic := range s.nics { - ref := nic.findEndpoint(protocol, addr, CanBePrimaryEndpoint) - if ref != nil { - ref.decRef() + if addressEndpoint := nic.findEndpoint(protocol, addr, CanBePrimaryEndpoint); addressEndpoint != nil { + addressEndpoint.DecRef() return nic.id } } @@ -1850,7 +1733,7 @@ func (s *Stack) LeaveGroup(protocol tcpip.NetworkProtocolNumber, nicID tcpip.NIC defer s.mu.RUnlock() if nic, ok := s.nics[nicID]; ok { - return nic.leaveGroup(multicastAddr) + return nic.leaveGroup(protocol, multicastAddr) } return tcpip.ErrUnknownNICID } @@ -1902,53 +1785,18 @@ func (s *Stack) AllowICMPMessage() bool { return s.icmpRateLimiter.Allow() } -// IsAddrTentative returns true if addr is tentative on the NIC with ID id. -// -// Note that if addr is not associated with a NIC with id ID, then this -// function will return false. It will only return true if the address is -// associated with the NIC AND it is tentative. -func (s *Stack) IsAddrTentative(id tcpip.NICID, addr tcpip.Address) (bool, *tcpip.Error) { - s.mu.RLock() - defer s.mu.RUnlock() - - nic, ok := s.nics[id] - if !ok { - return false, tcpip.ErrUnknownNICID - } - - return nic.isAddrTentative(addr), nil -} - -// DupTentativeAddrDetected attempts to inform the NIC with ID id that a -// tentative addr on it is a duplicate on a link. -func (s *Stack) DupTentativeAddrDetected(id tcpip.NICID, addr tcpip.Address) *tcpip.Error { - s.mu.Lock() - defer s.mu.Unlock() - - nic, ok := s.nics[id] - if !ok { - return tcpip.ErrUnknownNICID - } - - return nic.dupTentativeAddrDetected(addr) -} - -// SetNDPConfigurations sets the per-interface NDP configurations on the NIC -// with ID id to c. -// -// Note, if c contains invalid NDP configuration values, it will be fixed to -// use default values for the erroneous values. -func (s *Stack) SetNDPConfigurations(id tcpip.NICID, c NDPConfigurations) *tcpip.Error { +// GetNetworkEndpoint returns the NetworkEndpoint with the specified protocol +// number installed on the specified NIC. +func (s *Stack) GetNetworkEndpoint(nicID tcpip.NICID, proto tcpip.NetworkProtocolNumber) (NetworkEndpoint, *tcpip.Error) { s.mu.Lock() defer s.mu.Unlock() - nic, ok := s.nics[id] + nic, ok := s.nics[nicID] if !ok { - return tcpip.ErrUnknownNICID + return nil, tcpip.ErrUnknownNICID } - nic.setNDPConfigs(c) - return nil + return nic.networkEndpoints[proto], nil } // NUDConfigurations gets the per-interface NUD configurations. @@ -1961,7 +1809,7 @@ func (s *Stack) NUDConfigurations(id tcpip.NICID) (NUDConfigurations, *tcpip.Err return NUDConfigurations{}, tcpip.ErrUnknownNICID } - return nic.NUDConfigs() + return nic.nudConfigs() } // SetNUDConfigurations sets the per-interface NUD configurations. @@ -1980,22 +1828,6 @@ func (s *Stack) SetNUDConfigurations(id tcpip.NICID, c NUDConfigurations) *tcpip return nic.setNUDConfigs(c) } -// HandleNDPRA provides a NIC with ID id a validated NDP Router Advertisement -// message that it needs to handle. -func (s *Stack) HandleNDPRA(id tcpip.NICID, ip tcpip.Address, ra header.NDPRouterAdvert) *tcpip.Error { - s.mu.Lock() - defer s.mu.Unlock() - - nic, ok := s.nics[id] - if !ok { - return tcpip.ErrUnknownNICID - } - - nic.handleNDPRA(ip, ra) - - return nil -} - // Seed returns a 32 bit value that can be used as a seed value for port // picking, ISN generation etc. // @@ -2037,16 +1869,14 @@ func (s *Stack) FindNetworkEndpoint(netProto tcpip.NetworkProtocolNumber, addres defer s.mu.RUnlock() for _, nic := range s.nics { - id := NetworkEndpointID{address} - - if ref, ok := nic.mu.endpoints[id]; ok { - nic.mu.RLock() - defer nic.mu.RUnlock() - - // An endpoint with this id exists, check if it can be - // used and return it. - return ref.ep, nil + addressEndpoint := nic.getAddressOrCreateTempInner(netProto, address, false /* createTemp */, NeverPrimaryEndpoint) + if addressEndpoint == nil { + continue } + + ep := addressEndpoint.NetworkEndpoint() + addressEndpoint.DecRef() + return ep, nil } return nil, tcpip.ErrBadAddress } @@ -2063,3 +1893,8 @@ func (s *Stack) FindNICNameFromID(id tcpip.NICID) string { return nic.Name() } + +// NewJob returns a new tcpip.Job using the stack's clock. +func (s *Stack) NewJob(l sync.Locker, f func()) *tcpip.Job { + return tcpip.NewJob(s.clock, l, f) +} diff --git a/pkg/tcpip/stack/transport_demuxer.go b/pkg/tcpip/stack/transport_demuxer.go index 0774b5382..4ebc30ca8 100644 --- a/pkg/tcpip/stack/transport_demuxer.go +++ b/pkg/tcpip/stack/transport_demuxer.go @@ -155,7 +155,7 @@ func (epsByNIC *endpointsByNIC) transportEndpoints() []TransportEndpoint { func (epsByNIC *endpointsByNIC) handlePacket(r *Route, id TransportEndpointID, pkt *PacketBuffer) { epsByNIC.mu.RLock() - mpep, ok := epsByNIC.endpoints[r.ref.nic.ID()] + mpep, ok := epsByNIC.endpoints[r.nic.ID()] if !ok { if mpep, ok = epsByNIC.endpoints[0]; !ok { epsByNIC.mu.RUnlock() // Don't use defer for performance reasons. @@ -626,7 +626,7 @@ func (d *transportDemuxer) findTransportEndpoint(netProto tcpip.NetworkProtocolN epsByNIC.mu.RLock() eps.mu.RUnlock() - mpep, ok := epsByNIC.endpoints[r.ref.nic.ID()] + mpep, ok := epsByNIC.endpoints[r.nic.ID()] if !ok { if mpep, ok = epsByNIC.endpoints[0]; !ok { epsByNIC.mu.RUnlock() // Don't use defer for performance reasons. diff --git a/pkg/tcpip/tcpip.go b/pkg/tcpip/tcpip.go index 464608dee..0d4a803ff 100644 --- a/pkg/tcpip/tcpip.go +++ b/pkg/tcpip/tcpip.go @@ -237,6 +237,14 @@ type Timer interface { // network node. Or, in the case of unix endpoints, it may represent a path. type Address string +// WithPrefix returns the address with a prefix that represents a point subnet. +func (a Address) WithPrefix() AddressWithPrefix { + return AddressWithPrefix{ + Address: a, + PrefixLen: len(a) * 8, + } +} + // AddressMask is a bitmask for an address. type AddressMask string |