diff options
Diffstat (limited to 'pkg/tcpip/stack/ndp.go')
| -rw-r--r-- | pkg/tcpip/stack/ndp.go | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/pkg/tcpip/stack/ndp.go b/pkg/tcpip/stack/ndp.go index 03ddebdbd..d5352bb5f 100644 --- a/pkg/tcpip/stack/ndp.go +++ b/pkg/tcpip/stack/ndp.go @@ -38,6 +38,19 @@ const ( // Default = 1s (from RFC 4861 section 10). defaultRetransmitTimer = time.Second + // defaultHandleRAs is the default configuration for whether or not to + // handle incoming Router Advertisements as a host. + // + // Default = true. + defaultHandleRAs = true + + // defaultDiscoverDefaultRouters is the default configuration for + // whether or not to discover default routers from incoming Router + // Advertisements as a host. + // + // Default = true. + defaultDiscoverDefaultRouters = true + // minimumRetransmitTimer is the minimum amount of time to wait between // sending NDP Neighbor solicitation messages. Note, RFC 4861 does // not impose a minimum Retransmit Timer, but we do here to make sure @@ -49,6 +62,13 @@ const ( // // Min = 1ms. minimumRetransmitTimer = time.Millisecond + + // MaxDiscoveredDefaultRouters is the maximum number of discovered + // default routers. The stack should stop discovering new routers after + // discovering MaxDiscoveredDefaultRouters routers. + // + // Max = 10. + MaxDiscoveredDefaultRouters = 10 ) // NDPDispatcher is the interface integrators of netstack must implement to @@ -80,6 +100,15 @@ type NDPConfigurations struct { // // Must be greater than 0.5s. RetransmitTimer time.Duration + + // HandleRAs determines whether or not Router Advertisements will be + // 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 bool } // DefaultNDPConfigurations returns an NDPConfigurations populated with @@ -88,6 +117,8 @@ func DefaultNDPConfigurations() NDPConfigurations { return NDPConfigurations{ DupAddrDetectTransmits: defaultDupAddrDetectTransmits, RetransmitTimer: defaultRetransmitTimer, + HandleRAs: defaultHandleRAs, + DiscoverDefaultRouters: defaultDiscoverDefaultRouters, } } @@ -112,6 +143,9 @@ type ndpState struct { // The DAD state to send the next NS message, or resolve the address. dad map[tcpip.Address]dadState + + // The default routers discovered through Router Advertisements. + defaultRouters map[tcpip.Address]defaultRouterState } // dadState holds the Duplicate Address Detection timer and channel to signal @@ -127,6 +161,12 @@ type dadState struct { done *bool } +// defaultRouterState holds data associated with a default router discovered by +// a Router Advertisement. +type defaultRouterState struct { + invalidationTimer *time.Timer +} + // startDuplicateAddressDetection performs Duplicate Address Detection. // // This function must only be called by IPv6 addresses that are currently @@ -319,3 +359,18 @@ func (ndp *ndpState) stopDuplicateAddressDetection(addr tcpip.Address) { go ndp.nic.stack.ndpDisp.OnDuplicateAddressDetectionStatus(ndp.nic.ID(), addr, false, nil) } } + +// handleRA handles a Router Advertisement message that arrived on the NIC +// this ndp is for. +// +// The NIC 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? + if !ndp.configs.HandleRAs { + return + } + + // TODO(b/140882146): Do Router Discovery. + // TODO(b/140948104): Do Prefix Discovery. + // TODO(b/141556115): Do Parameter Discovery. +} |