diff options
| -rw-r--r-- | pkg/tcpip/header/ipv6.go | 49 | ||||
| -rw-r--r-- | pkg/tcpip/network/internal/ip/generic_multicast_protocol.go | 57 | ||||
| -rw-r--r-- | pkg/tcpip/network/ipv4/igmp.go | 12 | ||||
| -rw-r--r-- | pkg/tcpip/network/ipv6/mld.go | 20 |
4 files changed, 80 insertions, 58 deletions
diff --git a/pkg/tcpip/header/ipv6.go b/pkg/tcpip/header/ipv6.go index f2403978c..7711abec1 100644 --- a/pkg/tcpip/header/ipv6.go +++ b/pkg/tcpip/header/ipv6.go @@ -142,11 +142,6 @@ const ( // ipv6MulticastAddressScopeMask is the mask for the scope (scop) field, // within the byte holding the field, as per RFC 4291 section 2.7. ipv6MulticastAddressScopeMask = 0xF - - // ipv6LinkLocalMulticastScope is the value of the scope (scop) field within - // a multicast IPv6 address that indicates the address has link-local scope, - // as per RFC 4291 section 2.7. - ipv6LinkLocalMulticastScope = 2 ) // IPv6EmptySubnet is the empty IPv6 subnet. It may also be known as the @@ -399,7 +394,7 @@ func IsV6LoopbackAddress(addr tcpip.Address) bool { // IsV6LinkLocalMulticastAddress determines if the provided address is an IPv6 // link-local multicast address. func IsV6LinkLocalMulticastAddress(addr tcpip.Address) bool { - return IsV6MulticastAddress(addr) && addr[ipv6MulticastAddressScopeByteIdx]&ipv6MulticastAddressScopeMask == ipv6LinkLocalMulticastScope + return IsV6MulticastAddress(addr) && V6MulticastScope(addr) == IPv6LinkLocalMulticastScope } // AppendOpaqueInterfaceIdentifier appends a 64 bit opaque interface identifier @@ -520,3 +515,45 @@ func GenerateTempIPv6SLAACAddr(tempIIDHistory []byte, stableAddr tcpip.Address) PrefixLen: IIDOffsetInIPv6Address * 8, } } + +// IPv6MulticastScope is the scope of a multicast IPv6 address. +type IPv6MulticastScope uint8 + +// The various values for IPv6 multicast scopes, as per RFC 7346 section 2: +// +// +------+--------------------------+-------------------------+ +// | scop | NAME | REFERENCE | +// +------+--------------------------+-------------------------+ +// | 0 | Reserved | [RFC4291], RFC 7346 | +// | 1 | Interface-Local scope | [RFC4291], RFC 7346 | +// | 2 | Link-Local scope | [RFC4291], RFC 7346 | +// | 3 | Realm-Local scope | [RFC4291], RFC 7346 | +// | 4 | Admin-Local scope | [RFC4291], RFC 7346 | +// | 5 | Site-Local scope | [RFC4291], RFC 7346 | +// | 6 | Unassigned | | +// | 7 | Unassigned | | +// | 8 | Organization-Local scope | [RFC4291], RFC 7346 | +// | 9 | Unassigned | | +// | A | Unassigned | | +// | B | Unassigned | | +// | C | Unassigned | | +// | D | Unassigned | | +// | E | Global scope | [RFC4291], RFC 7346 | +// | F | Reserved | [RFC4291], RFC 7346 | +// +------+--------------------------+-------------------------+ +const ( + IPv6Reserved0MulticastScope = IPv6MulticastScope(0x0) + IPv6InterfaceLocalMulticastScope = IPv6MulticastScope(0x1) + IPv6LinkLocalMulticastScope = IPv6MulticastScope(0x2) + IPv6RealmLocalMulticastScope = IPv6MulticastScope(0x3) + IPv6AdminLocalMulticastScope = IPv6MulticastScope(0x4) + IPv6SiteLocalMulticastScope = IPv6MulticastScope(0x5) + IPv6OrganizationLocalMulticastScope = IPv6MulticastScope(0x8) + IPv6GlobalMulticastScope = IPv6MulticastScope(0xE) + IPv6ReservedFMulticastScope = IPv6MulticastScope(0xF) +) + +// V6MulticastScope returns the scope of a multicast address. +func V6MulticastScope(addr tcpip.Address) IPv6MulticastScope { + return IPv6MulticastScope(addr[ipv6MulticastAddressScopeByteIdx] & ipv6MulticastAddressScopeMask) +} diff --git a/pkg/tcpip/network/internal/ip/generic_multicast_protocol.go b/pkg/tcpip/network/internal/ip/generic_multicast_protocol.go index b9f129728..ac35d81e7 100644 --- a/pkg/tcpip/network/internal/ip/generic_multicast_protocol.go +++ b/pkg/tcpip/network/internal/ip/generic_multicast_protocol.go @@ -156,14 +156,6 @@ type GenericMulticastProtocolOptions struct { // // Unsolicited reports are transmitted when a group is newly joined. MaxUnsolicitedReportDelay time.Duration - - // AllNodesAddress is a multicast address that all nodes on a network should - // be a member of. - // - // This address will not have the generic multicast protocol performed on it; - // it will be left in the non member/listener state, and packets will never - // be sent for it. - AllNodesAddress tcpip.Address } // MulticastGroupProtocol is a multicast group protocol whose core state machine @@ -188,6 +180,10 @@ type MulticastGroupProtocol interface { // SendLeave sends a multicast leave for the specified group address. SendLeave(groupAddress tcpip.Address) tcpip.Error + + // ShouldPerformProtocol returns true iff the protocol should be performed for + // the specified group. + ShouldPerformProtocol(tcpip.Address) bool } // GenericMulticastProtocolState is the per interface generic multicast protocol @@ -455,20 +451,7 @@ func (g *GenericMulticastProtocolState) initializeNewMemberLocked(groupAddress t info.lastToSendReport = false - if groupAddress == g.opts.AllNodesAddress { - // As per RFC 2236 section 6 page 10 (for IGMPv2), - // - // The all-systems group (address 224.0.0.1) is handled as a special - // case. The host starts in Idle Member state for that group on every - // interface, never transitions to another state, and never sends a - // report for that group. - // - // As per RFC 2710 section 5 page 10 (for MLDv1), - // - // The link-scope all-nodes address (FF02::1) is handled as a special - // case. The node starts in Idle Listener state for that address on - // every interface, never transitions to another state, and never sends - // a Report or Done for that address. + if !g.opts.Protocol.ShouldPerformProtocol(groupAddress) { info.state = idleMember return } @@ -537,20 +520,7 @@ func (g *GenericMulticastProtocolState) maybeSendLeave(groupAddress tcpip.Addres return } - if groupAddress == g.opts.AllNodesAddress { - // As per RFC 2236 section 6 page 10 (for IGMPv2), - // - // The all-systems group (address 224.0.0.1) is handled as a special - // case. The host starts in Idle Member state for that group on every - // interface, never transitions to another state, and never sends a - // report for that group. - // - // As per RFC 2710 section 5 page 10 (for MLDv1), - // - // The link-scope all-nodes address (FF02::1) is handled as a special - // case. The node starts in Idle Listener state for that address on - // every interface, never transitions to another state, and never sends - // a Report or Done for that address. + if !g.opts.Protocol.ShouldPerformProtocol(groupAddress) { return } @@ -627,20 +597,7 @@ func (g *GenericMulticastProtocolState) setDelayTimerForAddressRLocked(groupAddr return } - if groupAddress == g.opts.AllNodesAddress { - // As per RFC 2236 section 6 page 10 (for IGMPv2), - // - // The all-systems group (address 224.0.0.1) is handled as a special - // case. The host starts in Idle Member state for that group on every - // interface, never transitions to another state, and never sends a - // report for that group. - // - // As per RFC 2710 section 5 page 10 (for MLDv1), - // - // The link-scope all-nodes address (FF02::1) is handled as a special - // case. The node starts in Idle Listener state for that address on - // every interface, never transitions to another state, and never sends - // a Report or Done for that address. + if !g.opts.Protocol.ShouldPerformProtocol(groupAddress) { return } diff --git a/pkg/tcpip/network/ipv4/igmp.go b/pkg/tcpip/network/ipv4/igmp.go index f3fc1c87e..b1ac29294 100644 --- a/pkg/tcpip/network/ipv4/igmp.go +++ b/pkg/tcpip/network/ipv4/igmp.go @@ -126,6 +126,17 @@ func (igmp *igmpState) SendLeave(groupAddress tcpip.Address) tcpip.Error { return err } +// ShouldPerformProtocol implements ip.MulticastGroupProtocol. +func (igmp *igmpState) ShouldPerformProtocol(groupAddress tcpip.Address) bool { + // As per RFC 2236 section 6 page 10, + // + // The all-systems group (address 224.0.0.1) is handled as a special + // case. The host starts in Idle Member state for that group on every + // interface, never transitions to another state, and never sends a + // report for that group. + return groupAddress != header.IPv4AllSystems +} + // init sets up an igmpState struct, and is required to be called before using // a new igmpState. // @@ -137,7 +148,6 @@ func (igmp *igmpState) init(ep *endpoint) { Clock: ep.protocol.stack.Clock(), Protocol: igmp, MaxUnsolicitedReportDelay: UnsolicitedReportIntervalMax, - AllNodesAddress: header.IPv4AllSystems, }) igmp.igmpV1Present = igmpV1PresentDefault igmp.igmpV1Job = ep.protocol.stack.NewJob(&ep.mu, func() { diff --git a/pkg/tcpip/network/ipv6/mld.go b/pkg/tcpip/network/ipv6/mld.go index dd153466d..538590baf 100644 --- a/pkg/tcpip/network/ipv6/mld.go +++ b/pkg/tcpip/network/ipv6/mld.go @@ -80,6 +80,25 @@ func (mld *mldState) SendLeave(groupAddress tcpip.Address) tcpip.Error { return err } +// ShouldPerformProtocol implements ip.MulticastGroupProtocol. +func (mld *mldState) ShouldPerformProtocol(groupAddress tcpip.Address) bool { + // As per RFC 2710 section 5 page 10, + // + // The link-scope all-nodes address (FF02::1) is handled as a special + // case. The node starts in Idle Listener state for that address on + // every interface, never transitions to another state, and never sends + // a Report or Done for that address. + // + // MLD messages are never sent for multicast addresses whose scope is 0 + // (reserved) or 1 (node-local). + if groupAddress == header.IPv6AllNodesMulticastAddress { + return false + } + + scope := header.V6MulticastScope(groupAddress) + return scope != header.IPv6Reserved0MulticastScope && scope != header.IPv6InterfaceLocalMulticastScope +} + // init sets up an mldState struct, and is required to be called before using // a new mldState. // @@ -91,7 +110,6 @@ func (mld *mldState) init(ep *endpoint) { Clock: ep.protocol.stack.Clock(), Protocol: mld, MaxUnsolicitedReportDelay: UnsolicitedReportIntervalMax, - AllNodesAddress: header.IPv6AllNodesMulticastAddress, }) } |