diff options
Diffstat (limited to 'pkg/tcpip/network')
-rw-r--r-- | pkg/tcpip/network/ipv6/icmp.go | 51 | ||||
-rw-r--r-- | pkg/tcpip/network/ipv6/icmp_test.go | 4 | ||||
-rw-r--r-- | pkg/tcpip/network/ipv6/ndp_test.go | 189 |
3 files changed, 240 insertions, 4 deletions
diff --git a/pkg/tcpip/network/ipv6/icmp.go b/pkg/tcpip/network/ipv6/icmp.go index c3f1dd488..05e8c075b 100644 --- a/pkg/tcpip/network/ipv6/icmp.go +++ b/pkg/tcpip/network/ipv6/icmp.go @@ -86,7 +86,8 @@ func (e *endpoint) handleICMP(r *stack.Route, netHeader buffer.View, vv buffer.V // As per RFC 4861 sections 4.1 - 4.5, 6.1.1, 6.1.2, 7.1.1, 7.1.2 and // 8.1, nodes MUST silently drop NDP packets where the Hop Limit field - // in the IPv6 header is not set to 255. + // in the IPv6 header is not set to 255, or the ICMPv6 Code field is not + // set to 0. switch h.Type() { case header.ICMPv6NeighborSolicit, header.ICMPv6NeighborAdvert, @@ -97,6 +98,11 @@ func (e *endpoint) handleICMP(r *stack.Route, netHeader buffer.View, vv buffer.V received.Invalid.Increment() return } + + if h.Code() != 0 { + received.Invalid.Increment() + return + } } // TODO(b/112892170): Meaningfully handle all ICMP types. @@ -309,8 +315,51 @@ func (e *endpoint) handleICMP(r *stack.Route, netHeader buffer.View, vv buffer.V received.RouterSolicit.Increment() case header.ICMPv6RouterAdvert: + routerAddr := iph.SourceAddress() + + // + // Validate the RA as per RFC 4861 section 6.1.2. + // + + // Is the IP Source Address a link-local address? + if !header.IsV6LinkLocalAddress(routerAddr) { + // ...No, silently drop the packet. + received.Invalid.Increment() + return + } + + p := h.NDPPayload() + + // Is the NDP payload of sufficient size to hold a Router + // Advertisement? + if len(p) < header.NDPRAMinimumSize { + // ...No, silently drop the packet. + received.Invalid.Increment() + return + } + + ra := header.NDPRouterAdvert(p) + opts := ra.Options() + + // Are options valid as per the wire format? + if _, err := opts.Iter(true); err != nil { + // ...No, silently drop the packet. + received.Invalid.Increment() + return + } + + // + // At this point, we have a valid Router Advertisement, as far + // as RFC 4861 section 6.1.2 is concerned. + // + received.RouterAdvert.Increment() + // Tell the NIC to handle the RA. + stack := r.Stack() + rxNICID := r.NICID() + stack.HandleNDPRA(rxNICID, routerAddr, ra) + case header.ICMPv6RedirectMsg: received.RedirectMsg.Increment() diff --git a/pkg/tcpip/network/ipv6/icmp_test.go b/pkg/tcpip/network/ipv6/icmp_test.go index b112303b6..d686f79ce 100644 --- a/pkg/tcpip/network/ipv6/icmp_test.go +++ b/pkg/tcpip/network/ipv6/icmp_test.go @@ -131,7 +131,7 @@ func TestICMPCounts(t *testing.T) { {header.ICMPv6EchoRequest, header.ICMPv6EchoMinimumSize}, {header.ICMPv6EchoReply, header.ICMPv6EchoMinimumSize}, {header.ICMPv6RouterSolicit, header.ICMPv6MinimumSize}, - {header.ICMPv6RouterAdvert, header.ICMPv6MinimumSize}, + {header.ICMPv6RouterAdvert, header.ICMPv6HeaderSize + header.NDPRAMinimumSize}, {header.ICMPv6NeighborSolicit, header.ICMPv6NeighborSolicitMinimumSize}, {header.ICMPv6NeighborAdvert, header.ICMPv6NeighborAdvertSize}, {header.ICMPv6RedirectMsg, header.ICMPv6MinimumSize}, @@ -426,7 +426,7 @@ func TestICMPChecksumValidationSimple(t *testing.T) { { "RouterAdvert", header.ICMPv6RouterAdvert, - header.ICMPv6MinimumSize, + header.ICMPv6HeaderSize + header.NDPRAMinimumSize, func(stats tcpip.ICMPv6ReceivedPacketStats) *tcpip.StatCounter { return stats.RouterAdvert }, diff --git a/pkg/tcpip/network/ipv6/ndp_test.go b/pkg/tcpip/network/ipv6/ndp_test.go index c32716f2e..69ab7ba12 100644 --- a/pkg/tcpip/network/ipv6/ndp_test.go +++ b/pkg/tcpip/network/ipv6/ndp_test.go @@ -21,6 +21,7 @@ import ( "gvisor.dev/gvisor/pkg/tcpip" "gvisor.dev/gvisor/pkg/tcpip/buffer" "gvisor.dev/gvisor/pkg/tcpip/header" + "gvisor.dev/gvisor/pkg/tcpip/link/channel" "gvisor.dev/gvisor/pkg/tcpip/stack" "gvisor.dev/gvisor/pkg/tcpip/transport/icmp" ) @@ -109,7 +110,7 @@ func TestHopLimitValidation(t *testing.T) { {"RouterSolicit", header.ICMPv6RouterSolicit, header.ICMPv6MinimumSize, func(stats tcpip.ICMPv6ReceivedPacketStats) *tcpip.StatCounter { return stats.RouterSolicit }}, - {"RouterAdvert", header.ICMPv6RouterAdvert, header.ICMPv6MinimumSize, func(stats tcpip.ICMPv6ReceivedPacketStats) *tcpip.StatCounter { + {"RouterAdvert", header.ICMPv6RouterAdvert, header.ICMPv6HeaderSize + header.NDPRAMinimumSize, func(stats tcpip.ICMPv6ReceivedPacketStats) *tcpip.StatCounter { return stats.RouterAdvert }}, {"NeighborSolicit", header.ICMPv6NeighborSolicit, header.ICMPv6NeighborSolicitMinimumSize, func(stats tcpip.ICMPv6ReceivedPacketStats) *tcpip.StatCounter { @@ -179,3 +180,189 @@ func TestHopLimitValidation(t *testing.T) { }) } } + +// TestRouterAdvertValidation tests that when the NIC is configured to handle +// NDP Router Advertisement packets, it validates the Router Advertisement +// properly before handling them. +func TestRouterAdvertValidation(t *testing.T) { + tests := []struct { + name string + src tcpip.Address + hopLimit uint8 + code uint8 + ndpPayload []byte + expectedSuccess bool + }{ + { + "OK", + lladdr0, + 255, + 0, + []byte{ + 0, 0, 0, 0, + 0, 0, 0, 0, + 0, 0, 0, 0, + }, + true, + }, + { + "NonLinkLocalSourceAddr", + addr1, + 255, + 0, + []byte{ + 0, 0, 0, 0, + 0, 0, 0, 0, + 0, 0, 0, 0, + }, + false, + }, + { + "HopLimitNot255", + lladdr0, + 254, + 0, + []byte{ + 0, 0, 0, 0, + 0, 0, 0, 0, + 0, 0, 0, 0, + }, + false, + }, + { + "NonZeroCode", + lladdr0, + 255, + 1, + []byte{ + 0, 0, 0, 0, + 0, 0, 0, 0, + 0, 0, 0, 0, + }, + false, + }, + { + "NDPPayloadTooSmall", + lladdr0, + 255, + 0, + []byte{ + 0, 0, 0, 0, + 0, 0, 0, 0, + 0, 0, 0, + }, + false, + }, + { + "OKWithOptions", + lladdr0, + 255, + 0, + []byte{ + // RA payload + 0, 0, 0, 0, + 0, 0, 0, 0, + 0, 0, 0, 0, + + // Option #1 (TargetLinkLayerAddress) + 2, 1, 0, 0, 0, 0, 0, 0, + + // Option #2 (unrecognized) + 255, 1, 0, 0, 0, 0, 0, 0, + + // Option #3 (PrefixInformation) + 3, 4, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, + }, + true, + }, + { + "OptionWithZeroLength", + lladdr0, + 255, + 0, + []byte{ + // RA payload + 0, 0, 0, 0, + 0, 0, 0, 0, + 0, 0, 0, 0, + + // Option #1 (TargetLinkLayerAddress) + // Invalid as it has 0 length. + 2, 0, 0, 0, 0, 0, 0, 0, + + // Option #2 (unrecognized) + 255, 1, 0, 0, 0, 0, 0, 0, + + // Option #3 (PrefixInformation) + 3, 4, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, + }, + false, + }, + } + + for _, test := range tests { + t.Run(test.name, func(t *testing.T) { + e := channel.New(10, 1280, linkAddr1) + s := stack.New(stack.Options{ + NetworkProtocols: []stack.NetworkProtocol{NewProtocol()}, + }) + + if err := s.CreateNIC(1, e); err != nil { + t.Fatalf("CreateNIC(_) = %s", err) + } + + icmpSize := header.ICMPv6HeaderSize + len(test.ndpPayload) + hdr := buffer.NewPrependable(header.IPv6MinimumSize + icmpSize) + pkt := header.ICMPv6(hdr.Prepend(icmpSize)) + pkt.SetType(header.ICMPv6RouterAdvert) + pkt.SetCode(test.code) + copy(pkt.NDPPayload(), test.ndpPayload) + payloadLength := hdr.UsedLength() + pkt.SetChecksum(header.ICMPv6Checksum(pkt, test.src, header.IPv6AllNodesMulticastAddress, buffer.VectorisedView{})) + ip := header.IPv6(hdr.Prepend(header.IPv6MinimumSize)) + ip.Encode(&header.IPv6Fields{ + PayloadLength: uint16(payloadLength), + NextHeader: uint8(icmp.ProtocolNumber6), + HopLimit: test.hopLimit, + SrcAddr: test.src, + DstAddr: header.IPv6AllNodesMulticastAddress, + }) + + stats := s.Stats().ICMP.V6PacketsReceived + invalid := stats.Invalid + rxRA := stats.RouterAdvert + + if got := invalid.Value(); got != 0 { + t.Fatalf("got invalid = %d, want = 0", got) + } + if got := rxRA.Value(); got != 0 { + t.Fatalf("got rxRA = %d, want = 0", got) + } + + e.Inject(header.IPv6ProtocolNumber, hdr.View().ToVectorisedView()) + + if test.expectedSuccess { + if got := invalid.Value(); got != 0 { + t.Fatalf("got invalid = %d, want = 0", got) + } + if got := rxRA.Value(); got != 1 { + t.Fatalf("got rxRA = %d, want = 1", got) + } + + } else { + if got := invalid.Value(); got != 1 { + t.Fatalf("got invalid = %d, want = 1", got) + } + if got := rxRA.Value(); got != 0 { + t.Fatalf("got rxRA = %d, want = 0", got) + } + } + }) + } +} |