diff options
Diffstat (limited to 'pkg/tcpip/header/checksum_test.go')
| -rw-r--r-- | pkg/tcpip/header/checksum_test.go | 203 |
1 files changed, 203 insertions, 0 deletions
diff --git a/pkg/tcpip/header/checksum_test.go b/pkg/tcpip/header/checksum_test.go index d267dabd0..3445511f4 100644 --- a/pkg/tcpip/header/checksum_test.go +++ b/pkg/tcpip/header/checksum_test.go @@ -23,6 +23,7 @@ import ( "sync" "testing" + "gvisor.dev/gvisor/pkg/tcpip" "gvisor.dev/gvisor/pkg/tcpip/buffer" "gvisor.dev/gvisor/pkg/tcpip/header" ) @@ -256,3 +257,205 @@ func TestICMPv6Checksum(t *testing.T) { }) }, want, fmt.Sprintf("header: {% x} data {% x}", h, vv.ToView())) } + +func randomAddress(size int) tcpip.Address { + s := make([]byte, size) + for i := 0; i < size; i++ { + s[i] = byte(rand.Uint32()) + } + return tcpip.Address(s) +} + +func TestChecksummableNetworkUpdateAddress(t *testing.T) { + tests := []struct { + name string + update func(header.IPv4, tcpip.Address) + }{ + { + name: "SetSourceAddressWithChecksumUpdate", + update: header.IPv4.SetSourceAddressWithChecksumUpdate, + }, + { + name: "SetDestinationAddressWithChecksumUpdate", + update: header.IPv4.SetDestinationAddressWithChecksumUpdate, + }, + } + + for _, test := range tests { + t.Run(test.name, func(t *testing.T) { + for i := 0; i < 1000; i++ { + var origBytes [header.IPv4MinimumSize]byte + header.IPv4(origBytes[:]).Encode(&header.IPv4Fields{ + TOS: 1, + TotalLength: header.IPv4MinimumSize, + ID: 2, + Flags: 3, + FragmentOffset: 4, + TTL: 5, + Protocol: 6, + Checksum: 0, + SrcAddr: randomAddress(header.IPv4AddressSize), + DstAddr: randomAddress(header.IPv4AddressSize), + }) + + addr := randomAddress(header.IPv4AddressSize) + + bytesCopy := origBytes + h := header.IPv4(bytesCopy[:]) + origXSum := h.CalculateChecksum() + h.SetChecksum(^origXSum) + + test.update(h, addr) + got := ^h.Checksum() + h.SetChecksum(0) + want := h.CalculateChecksum() + if got != want { + t.Errorf("got h.Checksum() = 0x%x, want = 0x%x; originalBytes = 0x%x, new addr = %s", got, want, origBytes, addr) + } + } + }) + } +} + +func TestChecksummableTransportUpdatePort(t *testing.T) { + // The fields in the pseudo header is not tested here so we just use 0. + const pseudoHeaderXSum = 0 + + tests := []struct { + name string + transportHdr func(_, _ uint16) (header.ChecksummableTransport, func(uint16) uint16) + proto tcpip.TransportProtocolNumber + }{ + { + name: "TCP", + transportHdr: func(src, dst uint16) (header.ChecksummableTransport, func(uint16) uint16) { + h := header.TCP(make([]byte, header.TCPMinimumSize)) + h.Encode(&header.TCPFields{ + SrcPort: src, + DstPort: dst, + SeqNum: 1, + AckNum: 2, + DataOffset: header.TCPMinimumSize, + Flags: 3, + WindowSize: 4, + Checksum: 0, + UrgentPointer: 5, + }) + h.SetChecksum(^h.CalculateChecksum(pseudoHeaderXSum)) + return h, h.CalculateChecksum + }, + proto: header.TCPProtocolNumber, + }, + { + name: "UDP", + transportHdr: func(src, dst uint16) (header.ChecksummableTransport, func(uint16) uint16) { + h := header.UDP(make([]byte, header.UDPMinimumSize)) + h.Encode(&header.UDPFields{ + SrcPort: src, + DstPort: dst, + Length: 0, + Checksum: 0, + }) + h.SetChecksum(^h.CalculateChecksum(pseudoHeaderXSum)) + return h, h.CalculateChecksum + }, + proto: header.UDPProtocolNumber, + }, + } + + for i := 0; i < 1000; i++ { + origSrcPort := uint16(rand.Uint32()) + origDstPort := uint16(rand.Uint32()) + newPort := uint16(rand.Uint32()) + + t.Run(fmt.Sprintf("OrigSrcPort=%d,OrigDstPort=%d,NewPort=%d", origSrcPort, origDstPort, newPort), func(*testing.T) { + for _, test := range tests { + t.Run(test.name, func(t *testing.T) { + for _, subTest := range []struct { + name string + update func(header.ChecksummableTransport) + }{ + { + name: "Source port", + update: func(h header.ChecksummableTransport) { h.SetSourcePortWithChecksumUpdate(newPort) }, + }, + { + name: "Destination port", + update: func(h header.ChecksummableTransport) { h.SetDestinationPortWithChecksumUpdate(newPort) }, + }, + } { + t.Run(subTest.name, func(t *testing.T) { + h, calcXSum := test.transportHdr(origSrcPort, origDstPort) + subTest.update(h) + // TCP and UDP hold the 1s complement of the fully calculated + // checksum. + got := ^h.Checksum() + h.SetChecksum(0) + + if want := calcXSum(pseudoHeaderXSum); got != want { + h, _ := test.transportHdr(origSrcPort, origDstPort) + t.Errorf("got Checksum() = 0x%x, want = 0x%x; originalBytes = %#v, new port = %d", got, want, h, newPort) + } + }) + } + }) + } + }) + } +} + +func TestChecksummableTransportUpdatePseudoHeaderAddress(t *testing.T) { + const addressSize = 6 + + tests := []struct { + name string + transportHdr func() header.ChecksummableTransport + proto tcpip.TransportProtocolNumber + }{ + { + name: "TCP", + transportHdr: func() header.ChecksummableTransport { return header.TCP(make([]byte, header.TCPMinimumSize)) }, + proto: header.TCPProtocolNumber, + }, + { + name: "UDP", + transportHdr: func() header.ChecksummableTransport { return header.UDP(make([]byte, header.UDPMinimumSize)) }, + proto: header.UDPProtocolNumber, + }, + } + + for i := 0; i < 1000; i++ { + permanent := randomAddress(addressSize) + old := randomAddress(addressSize) + new := randomAddress(addressSize) + + t.Run(fmt.Sprintf("Permanent=%q,Old=%q,New=%q", permanent, old, new), func(t *testing.T) { + for _, test := range tests { + t.Run(test.name, func(t *testing.T) { + for _, fullChecksum := range []bool{true, false} { + t.Run(fmt.Sprintf("FullChecksum=%t", fullChecksum), func(t *testing.T) { + initialXSum := header.PseudoHeaderChecksum(test.proto, permanent, old, 0) + if fullChecksum { + // TCP and UDP hold the 1s complement of the fully calculated + // checksum. + initialXSum = ^initialXSum + } + + h := test.transportHdr() + h.SetChecksum(initialXSum) + h.UpdateChecksumPseudoHeaderAddress(old, new, fullChecksum) + + got := h.Checksum() + if fullChecksum { + got = ^got + } + if want := header.PseudoHeaderChecksum(test.proto, permanent, new, 0); got != want { + t.Errorf("got Checksum() = 0x%x, want = 0x%x; h = %#v", got, want, h) + } + }) + } + }) + } + }) + } +} |