diff options
| -rw-r--r-- | pkg/tcpip/network/fragmentation/fragmentation.go | 3 | ||||
| -rw-r--r-- | pkg/tcpip/network/fragmentation/fragmentation_test.go | 12 | ||||
| -rw-r--r-- | pkg/tcpip/network/ipv4/ipv4.go | 12 | ||||
| -rw-r--r-- | pkg/tcpip/network/ipv6/ipv6.go | 12 |
4 files changed, 30 insertions, 9 deletions
diff --git a/pkg/tcpip/network/fragmentation/fragmentation.go b/pkg/tcpip/network/fragmentation/fragmentation.go index 888ad62a3..ed502a473 100644 --- a/pkg/tcpip/network/fragmentation/fragmentation.go +++ b/pkg/tcpip/network/fragmentation/fragmentation.go @@ -29,9 +29,6 @@ import ( ) const ( - // DefaultReassembleTimeout is based on the linux stack: net.ipv4.ipfrag_time. - DefaultReassembleTimeout = 30 * time.Second - // HighFragThreshold is the threshold at which we start trimming old // fragmented packets. Linux uses a default value of 4 MB. See // net.ipv4.ipfrag_high_thresh for more information. diff --git a/pkg/tcpip/network/fragmentation/fragmentation_test.go b/pkg/tcpip/network/fragmentation/fragmentation_test.go index 31a1eb862..d3c7d7f92 100644 --- a/pkg/tcpip/network/fragmentation/fragmentation_test.go +++ b/pkg/tcpip/network/fragmentation/fragmentation_test.go @@ -26,6 +26,10 @@ import ( "gvisor.dev/gvisor/pkg/tcpip/network/testutil" ) +// reassembleTimeout is dummy timeout used for testing, where the clock never +// advances. +const reassembleTimeout = 1 + // vv is a helper to build VectorisedView from different strings. func vv(size int, pieces ...string) buffer.VectorisedView { views := make([]buffer.View, len(pieces)) @@ -98,7 +102,7 @@ var processTestCases = []struct { func TestFragmentationProcess(t *testing.T) { for _, c := range processTestCases { t.Run(c.comment, func(t *testing.T) { - f := NewFragmentation(minBlockSize, 1024, 512, DefaultReassembleTimeout, &faketime.NullClock{}) + f := NewFragmentation(minBlockSize, 1024, 512, reassembleTimeout, &faketime.NullClock{}) firstFragmentProto := c.in[0].proto for i, in := range c.in { vv, proto, done, err := f.Process(in.id, in.first, in.last, in.more, in.proto, in.vv) @@ -253,7 +257,7 @@ func TestReassemblingTimeout(t *testing.T) { } func TestMemoryLimits(t *testing.T) { - f := NewFragmentation(minBlockSize, 3, 1, DefaultReassembleTimeout, &faketime.NullClock{}) + f := NewFragmentation(minBlockSize, 3, 1, reassembleTimeout, &faketime.NullClock{}) // Send first fragment with id = 0. f.Process(FragmentID{ID: 0}, 0, 0, true, 0xFF, vv(1, "0")) // Send first fragment with id = 1. @@ -277,7 +281,7 @@ func TestMemoryLimits(t *testing.T) { } func TestMemoryLimitsIgnoresDuplicates(t *testing.T) { - f := NewFragmentation(minBlockSize, 1, 0, DefaultReassembleTimeout, &faketime.NullClock{}) + f := NewFragmentation(minBlockSize, 1, 0, reassembleTimeout, &faketime.NullClock{}) // Send first fragment with id = 0. f.Process(FragmentID{}, 0, 0, true, 0xFF, vv(1, "0")) // Send the same packet again. @@ -372,7 +376,7 @@ func TestErrors(t *testing.T) { for _, test := range tests { t.Run(test.name, func(t *testing.T) { - f := NewFragmentation(test.blockSize, HighFragThreshold, LowFragThreshold, DefaultReassembleTimeout, &faketime.NullClock{}) + f := NewFragmentation(test.blockSize, HighFragThreshold, LowFragThreshold, reassembleTimeout, &faketime.NullClock{}) _, _, done, err := f.Process(FragmentID{}, test.first, test.last, test.more, 0, vv(len(test.data), test.data)) if !errors.Is(err, test.err) { t.Errorf("got Process(_, %d, %d, %t, _, %q) = (_, _, _, %v), want = (_, _, _, %v)", test.first, test.last, test.more, test.data, err, test.err) diff --git a/pkg/tcpip/network/ipv4/ipv4.go b/pkg/tcpip/network/ipv4/ipv4.go index 79c939129..99274dd45 100644 --- a/pkg/tcpip/network/ipv4/ipv4.go +++ b/pkg/tcpip/network/ipv4/ipv4.go @@ -18,6 +18,7 @@ package ipv4 import ( "fmt" "sync/atomic" + "time" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/tcpip" @@ -30,6 +31,15 @@ import ( ) const ( + // As per RFC 791 section 3.2: + // The current recommendation for the initial timer setting is 15 seconds. + // This may be changed as experience with this protocol accumulates. + // + // Considering that it is an old recommendation, we use the same reassembly + // timeout that linux defines, which is 30 seconds: + // https://github.com/torvalds/linux/blob/47ec5303d73ea344e84f46660fff693c57641386/include/net/ip.h#L138 + reassembleTimeout = 30 * time.Second + // ProtocolNumber is the ipv4 protocol number. ProtocolNumber = header.IPv4ProtocolNumber @@ -785,7 +795,7 @@ func NewProtocol(s *stack.Stack) stack.NetworkProtocol { ids: ids, hashIV: hashIV, defaultTTL: DefaultTTL, - fragmentation: fragmentation.NewFragmentation(fragmentblockSize, fragmentation.HighFragThreshold, fragmentation.LowFragThreshold, fragmentation.DefaultReassembleTimeout, s.Clock()), + fragmentation: fragmentation.NewFragmentation(fragmentblockSize, fragmentation.HighFragThreshold, fragmentation.LowFragThreshold, reassembleTimeout, s.Clock()), } } diff --git a/pkg/tcpip/network/ipv6/ipv6.go b/pkg/tcpip/network/ipv6/ipv6.go index 73e50f8d6..826342c4f 100644 --- a/pkg/tcpip/network/ipv6/ipv6.go +++ b/pkg/tcpip/network/ipv6/ipv6.go @@ -21,6 +21,7 @@ import ( "hash/fnv" "sort" "sync/atomic" + "time" "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/tcpip" @@ -33,6 +34,15 @@ import ( ) const ( + // As per RFC 8200 section 4.5: + // If insufficient fragments are received to complete reassembly of a packet + // within 60 seconds of the reception of the first-arriving fragment of that + // packet, reassembly of that packet must be abandoned. + // + // Linux also uses 60 seconds for reassembly timeout: + // https://github.com/torvalds/linux/blob/47ec5303d73ea344e84f46660fff693c57641386/include/net/ipv6.h#L456 + reassembleTimeout = 60 * time.Second + // ProtocolNumber is the ipv6 protocol number. ProtocolNumber = header.IPv6ProtocolNumber @@ -1459,7 +1469,7 @@ func NewProtocolWithOptions(opts Options) stack.NetworkProtocolFactory { return func(s *stack.Stack) stack.NetworkProtocol { p := &protocol{ stack: s, - fragmentation: fragmentation.NewFragmentation(header.IPv6FragmentExtHdrFragmentOffsetBytesPerUnit, fragmentation.HighFragThreshold, fragmentation.LowFragThreshold, fragmentation.DefaultReassembleTimeout, s.Clock()), + fragmentation: fragmentation.NewFragmentation(header.IPv6FragmentExtHdrFragmentOffsetBytesPerUnit, fragmentation.HighFragThreshold, fragmentation.LowFragThreshold, reassembleTimeout, s.Clock()), ids: ids, hashIV: hashIV, |