diff options
Diffstat (limited to 'pkg/tcpip/checker')
| -rw-r--r-- | pkg/tcpip/checker/BUILD | 16 | ||||
| -rw-r--r-- | pkg/tcpip/checker/checker.go | 588 |
2 files changed, 0 insertions, 604 deletions
diff --git a/pkg/tcpip/checker/BUILD b/pkg/tcpip/checker/BUILD deleted file mode 100644 index f597d0b24..000000000 --- a/pkg/tcpip/checker/BUILD +++ /dev/null @@ -1,16 +0,0 @@ -load("//tools/go_stateify:defs.bzl", "go_library") - -package(licenses = ["notice"]) - -go_library( - name = "checker", - testonly = 1, - srcs = ["checker.go"], - importpath = "gvisor.googlesource.com/gvisor/pkg/tcpip/checker", - visibility = ["//visibility:public"], - deps = [ - "//pkg/tcpip", - "//pkg/tcpip/header", - "//pkg/tcpip/seqnum", - ], -) diff --git a/pkg/tcpip/checker/checker.go b/pkg/tcpip/checker/checker.go deleted file mode 100644 index 6e7edf3ab..000000000 --- a/pkg/tcpip/checker/checker.go +++ /dev/null @@ -1,588 +0,0 @@ -// Copyright 2018 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -// Package checker provides helper functions to check networking packets for -// validity. -package checker - -import ( - "encoding/binary" - "reflect" - "testing" - - "gvisor.googlesource.com/gvisor/pkg/tcpip" - "gvisor.googlesource.com/gvisor/pkg/tcpip/header" - "gvisor.googlesource.com/gvisor/pkg/tcpip/seqnum" -) - -// NetworkChecker is a function to check a property of a network packet. -type NetworkChecker func(*testing.T, []header.Network) - -// TransportChecker is a function to check a property of a transport packet. -type TransportChecker func(*testing.T, header.Transport) - -// IPv4 checks the validity and properties of the given IPv4 packet. It is -// expected to be used in conjunction with other network checkers for specific -// properties. For example, to check the source and destination address, one -// would call: -// -// checker.IPv4(t, b, checker.SrcAddr(x), checker.DstAddr(y)) -func IPv4(t *testing.T, b []byte, checkers ...NetworkChecker) { - t.Helper() - - ipv4 := header.IPv4(b) - - if !ipv4.IsValid(len(b)) { - t.Error("Not a valid IPv4 packet") - } - - xsum := ipv4.CalculateChecksum() - if xsum != 0 && xsum != 0xffff { - t.Errorf("Bad checksum: 0x%x, checksum in packet: 0x%x", xsum, ipv4.Checksum()) - } - - for _, f := range checkers { - f(t, []header.Network{ipv4}) - } - if t.Failed() { - t.FailNow() - } -} - -// IPv6 checks the validity and properties of the given IPv6 packet. The usage -// is similar to IPv4. -func IPv6(t *testing.T, b []byte, checkers ...NetworkChecker) { - t.Helper() - - ipv6 := header.IPv6(b) - if !ipv6.IsValid(len(b)) { - t.Error("Not a valid IPv6 packet") - } - - for _, f := range checkers { - f(t, []header.Network{ipv6}) - } - if t.Failed() { - t.FailNow() - } -} - -// SrcAddr creates a checker that checks the source address. -func SrcAddr(addr tcpip.Address) NetworkChecker { - return func(t *testing.T, h []header.Network) { - t.Helper() - - if a := h[0].SourceAddress(); a != addr { - t.Errorf("Bad source address, got %v, want %v", a, addr) - } - } -} - -// DstAddr creates a checker that checks the destination address. -func DstAddr(addr tcpip.Address) NetworkChecker { - return func(t *testing.T, h []header.Network) { - t.Helper() - - if a := h[0].DestinationAddress(); a != addr { - t.Errorf("Bad destination address, got %v, want %v", a, addr) - } - } -} - -// TTL creates a checker that checks the TTL (ipv4) or HopLimit (ipv6). -func TTL(ttl uint8) NetworkChecker { - return func(t *testing.T, h []header.Network) { - var v uint8 - switch ip := h[0].(type) { - case header.IPv4: - v = ip.TTL() - case header.IPv6: - v = ip.HopLimit() - } - if v != ttl { - t.Fatalf("Bad TTL, got %v, want %v", v, ttl) - } - } -} - -// PayloadLen creates a checker that checks the payload length. -func PayloadLen(plen int) NetworkChecker { - return func(t *testing.T, h []header.Network) { - t.Helper() - - if l := len(h[0].Payload()); l != plen { - t.Errorf("Bad payload length, got %v, want %v", l, plen) - } - } -} - -// FragmentOffset creates a checker that checks the FragmentOffset field. -func FragmentOffset(offset uint16) NetworkChecker { - return func(t *testing.T, h []header.Network) { - t.Helper() - - // We only do this of IPv4 for now. - switch ip := h[0].(type) { - case header.IPv4: - if v := ip.FragmentOffset(); v != offset { - t.Errorf("Bad fragment offset, got %v, want %v", v, offset) - } - } - } -} - -// FragmentFlags creates a checker that checks the fragment flags field. -func FragmentFlags(flags uint8) NetworkChecker { - return func(t *testing.T, h []header.Network) { - t.Helper() - - // We only do this of IPv4 for now. - switch ip := h[0].(type) { - case header.IPv4: - if v := ip.Flags(); v != flags { - t.Errorf("Bad fragment offset, got %v, want %v", v, flags) - } - } - } -} - -// TOS creates a checker that checks the TOS field. -func TOS(tos uint8, label uint32) NetworkChecker { - return func(t *testing.T, h []header.Network) { - t.Helper() - - if v, l := h[0].TOS(); v != tos || l != label { - t.Errorf("Bad TOS, got (%v, %v), want (%v,%v)", v, l, tos, label) - } - } -} - -// Raw creates a checker that checks the bytes of payload. -// The checker always checks the payload of the last network header. -// For instance, in case of IPv6 fragments, the payload that will be checked -// is the one containing the actual data that the packet is carrying, without -// the bytes added by the IPv6 fragmentation. -func Raw(want []byte) NetworkChecker { - return func(t *testing.T, h []header.Network) { - t.Helper() - - if got := h[len(h)-1].Payload(); !reflect.DeepEqual(got, want) { - t.Errorf("Wrong payload, got %v, want %v", got, want) - } - } -} - -// IPv6Fragment creates a checker that validates an IPv6 fragment. -func IPv6Fragment(checkers ...NetworkChecker) NetworkChecker { - return func(t *testing.T, h []header.Network) { - t.Helper() - - if p := h[0].TransportProtocol(); p != header.IPv6FragmentHeader { - t.Errorf("Bad protocol, got %v, want %v", p, header.UDPProtocolNumber) - } - - ipv6Frag := header.IPv6Fragment(h[0].Payload()) - if !ipv6Frag.IsValid() { - t.Error("Not a valid IPv6 fragment") - } - - for _, f := range checkers { - f(t, []header.Network{h[0], ipv6Frag}) - } - if t.Failed() { - t.FailNow() - } - } -} - -// TCP creates a checker that checks that the transport protocol is TCP and -// potentially additional transport header fields. -func TCP(checkers ...TransportChecker) NetworkChecker { - return func(t *testing.T, h []header.Network) { - t.Helper() - - first := h[0] - last := h[len(h)-1] - - if p := last.TransportProtocol(); p != header.TCPProtocolNumber { - t.Errorf("Bad protocol, got %v, want %v", p, header.TCPProtocolNumber) - } - - // Verify the checksum. - tcp := header.TCP(last.Payload()) - l := uint16(len(tcp)) - - xsum := header.Checksum([]byte(first.SourceAddress()), 0) - xsum = header.Checksum([]byte(first.DestinationAddress()), xsum) - xsum = header.Checksum([]byte{0, byte(last.TransportProtocol())}, xsum) - xsum = header.Checksum([]byte{byte(l >> 8), byte(l)}, xsum) - xsum = header.Checksum(tcp, xsum) - - if xsum != 0 && xsum != 0xffff { - t.Errorf("Bad checksum: 0x%x, checksum in segment: 0x%x", xsum, tcp.Checksum()) - } - - // Run the transport checkers. - for _, f := range checkers { - f(t, tcp) - } - if t.Failed() { - t.FailNow() - } - } -} - -// UDP creates a checker that checks that the transport protocol is UDP and -// potentially additional transport header fields. -func UDP(checkers ...TransportChecker) NetworkChecker { - return func(t *testing.T, h []header.Network) { - t.Helper() - - last := h[len(h)-1] - - if p := last.TransportProtocol(); p != header.UDPProtocolNumber { - t.Errorf("Bad protocol, got %v, want %v", p, header.UDPProtocolNumber) - } - - udp := header.UDP(last.Payload()) - for _, f := range checkers { - f(t, udp) - } - if t.Failed() { - t.FailNow() - } - } -} - -// SrcPort creates a checker that checks the source port. -func SrcPort(port uint16) TransportChecker { - return func(t *testing.T, h header.Transport) { - t.Helper() - - if p := h.SourcePort(); p != port { - t.Errorf("Bad source port, got %v, want %v", p, port) - } - } -} - -// DstPort creates a checker that checks the destination port. -func DstPort(port uint16) TransportChecker { - return func(t *testing.T, h header.Transport) { - if p := h.DestinationPort(); p != port { - t.Errorf("Bad destination port, got %v, want %v", p, port) - } - } -} - -// SeqNum creates a checker that checks the sequence number. -func SeqNum(seq uint32) TransportChecker { - return func(t *testing.T, h header.Transport) { - t.Helper() - - tcp, ok := h.(header.TCP) - if !ok { - return - } - - if s := tcp.SequenceNumber(); s != seq { - t.Errorf("Bad sequence number, got %v, want %v", s, seq) - } - } -} - -// AckNum creates a checker that checks the ack number. -func AckNum(seq uint32) TransportChecker { - return func(t *testing.T, h header.Transport) { - t.Helper() - tcp, ok := h.(header.TCP) - if !ok { - return - } - - if s := tcp.AckNumber(); s != seq { - t.Errorf("Bad ack number, got %v, want %v", s, seq) - } - } -} - -// Window creates a checker that checks the tcp window. -func Window(window uint16) TransportChecker { - return func(t *testing.T, h header.Transport) { - tcp, ok := h.(header.TCP) - if !ok { - return - } - - if w := tcp.WindowSize(); w != window { - t.Errorf("Bad window, got 0x%x, want 0x%x", w, window) - } - } -} - -// TCPFlags creates a checker that checks the tcp flags. -func TCPFlags(flags uint8) TransportChecker { - return func(t *testing.T, h header.Transport) { - t.Helper() - - tcp, ok := h.(header.TCP) - if !ok { - return - } - - if f := tcp.Flags(); f != flags { - t.Errorf("Bad flags, got 0x%x, want 0x%x", f, flags) - } - } -} - -// TCPFlagsMatch creates a checker that checks that the tcp flags, masked by the -// given mask, match the supplied flags. -func TCPFlagsMatch(flags, mask uint8) TransportChecker { - return func(t *testing.T, h header.Transport) { - tcp, ok := h.(header.TCP) - if !ok { - return - } - - if f := tcp.Flags(); (f & mask) != (flags & mask) { - t.Errorf("Bad masked flags, got 0x%x, want 0x%x, mask 0x%x", f, flags, mask) - } - } -} - -// TCPSynOptions creates a checker that checks the presence of TCP options in -// SYN segments. -// -// If wndscale is negative, the window scale option must not be present. -func TCPSynOptions(wantOpts header.TCPSynOptions) TransportChecker { - return func(t *testing.T, h header.Transport) { - tcp, ok := h.(header.TCP) - if !ok { - return - } - opts := tcp.Options() - limit := len(opts) - foundMSS := false - foundWS := false - foundTS := false - foundSACKPermitted := false - tsVal := uint32(0) - tsEcr := uint32(0) - for i := 0; i < limit; { - switch opts[i] { - case header.TCPOptionEOL: - i = limit - case header.TCPOptionNOP: - i++ - case header.TCPOptionMSS: - v := uint16(opts[i+2])<<8 | uint16(opts[i+3]) - if wantOpts.MSS != v { - t.Errorf("Bad MSS: got %v, want %v", v, wantOpts.MSS) - } - foundMSS = true - i += 4 - case header.TCPOptionWS: - if wantOpts.WS < 0 { - t.Error("WS present when it shouldn't be") - } - v := int(opts[i+2]) - if v != wantOpts.WS { - t.Errorf("Bad WS: got %v, want %v", v, wantOpts.WS) - } - foundWS = true - i += 3 - case header.TCPOptionTS: - if i+9 >= limit { - t.Errorf("TS Option truncated , option is only: %d bytes, want 10", limit-i) - } - if opts[i+1] != 10 { - t.Errorf("Bad length %d for TS option, limit: %d", opts[i+1], limit) - } - tsVal = binary.BigEndian.Uint32(opts[i+2:]) - tsEcr = uint32(0) - if tcp.Flags()&header.TCPFlagAck != 0 { - // If the syn is an SYN-ACK then read - // the tsEcr value as well. - tsEcr = binary.BigEndian.Uint32(opts[i+6:]) - } - foundTS = true - i += 10 - case header.TCPOptionSACKPermitted: - if i+1 >= limit { - t.Errorf("SACKPermitted option truncated, option is only : %d bytes, want 2", limit-i) - } - if opts[i+1] != 2 { - t.Errorf("Bad length %d for SACKPermitted option, limit: %d", opts[i+1], limit) - } - foundSACKPermitted = true - i += 2 - - default: - i += int(opts[i+1]) - } - } - - if !foundMSS { - t.Errorf("MSS option not found. Options: %x", opts) - } - - if !foundWS && wantOpts.WS >= 0 { - t.Errorf("WS option not found. Options: %x", opts) - } - if wantOpts.TS && !foundTS { - t.Errorf("TS option not found. Options: %x", opts) - } - if foundTS && tsVal == 0 { - t.Error("TS option specified but the timestamp value is zero") - } - if foundTS && tsEcr == 0 && wantOpts.TSEcr != 0 { - t.Errorf("TS option specified but TSEcr is incorrect: got %d, want: %d", tsEcr, wantOpts.TSEcr) - } - if wantOpts.SACKPermitted && !foundSACKPermitted { - t.Errorf("SACKPermitted option not found. Options: %x", opts) - } - } -} - -// TCPTimestampChecker creates a checker that validates that a TCP segment has a -// TCP Timestamp option if wantTS is true, it also compares the wantTSVal and -// wantTSEcr values with those in the TCP segment (if present). -// -// If wantTSVal or wantTSEcr is zero then the corresponding comparison is -// skipped. -func TCPTimestampChecker(wantTS bool, wantTSVal uint32, wantTSEcr uint32) TransportChecker { - return func(t *testing.T, h header.Transport) { - tcp, ok := h.(header.TCP) - if !ok { - return - } - opts := []byte(tcp.Options()) - limit := len(opts) - foundTS := false - tsVal := uint32(0) - tsEcr := uint32(0) - for i := 0; i < limit; { - switch opts[i] { - case header.TCPOptionEOL: - i = limit - case header.TCPOptionNOP: - i++ - case header.TCPOptionTS: - if i+9 >= limit { - t.Errorf("TS option found, but option is truncated, option length: %d, want 10 bytes", limit-i) - } - if opts[i+1] != 10 { - t.Errorf("TS option found, but bad length specified: %d, want: 10", opts[i+1]) - } - tsVal = binary.BigEndian.Uint32(opts[i+2:]) - tsEcr = binary.BigEndian.Uint32(opts[i+6:]) - foundTS = true - i += 10 - default: - // We don't recognize this option, just skip over it. - if i+2 > limit { - return - } - l := int(opts[i+1]) - if i < 2 || i+l > limit { - return - } - i += l - } - } - - if wantTS != foundTS { - t.Errorf("TS Option mismatch: got TS= %v, want TS= %v", foundTS, wantTS) - } - if wantTS && wantTSVal != 0 && wantTSVal != tsVal { - t.Errorf("Timestamp value is incorrect: got: %d, want: %d", tsVal, wantTSVal) - } - if wantTS && wantTSEcr != 0 && tsEcr != wantTSEcr { - t.Errorf("Timestamp Echo Reply is incorrect: got: %d, want: %d", tsEcr, wantTSEcr) - } - } -} - -// TCPNoSACKBlockChecker creates a checker that verifies that the segment does not -// contain any SACK blocks in the TCP options. -func TCPNoSACKBlockChecker() TransportChecker { - return TCPSACKBlockChecker(nil) -} - -// TCPSACKBlockChecker creates a checker that verifies that the segment does -// contain the specified SACK blocks in the TCP options. -func TCPSACKBlockChecker(sackBlocks []header.SACKBlock) TransportChecker { - return func(t *testing.T, h header.Transport) { - t.Helper() - tcp, ok := h.(header.TCP) - if !ok { - return - } - var gotSACKBlocks []header.SACKBlock - - opts := []byte(tcp.Options()) - limit := len(opts) - for i := 0; i < limit; { - switch opts[i] { - case header.TCPOptionEOL: - i = limit - case header.TCPOptionNOP: - i++ - case header.TCPOptionSACK: - if i+2 > limit { - // Malformed SACK block. - t.Errorf("malformed SACK option in options: %v", opts) - } - sackOptionLen := int(opts[i+1]) - if i+sackOptionLen > limit || (sackOptionLen-2)%8 != 0 { - // Malformed SACK block. - t.Errorf("malformed SACK option length in options: %v", opts) - } - numBlocks := sackOptionLen / 8 - for j := 0; j < numBlocks; j++ { - start := binary.BigEndian.Uint32(opts[i+2+j*8:]) - end := binary.BigEndian.Uint32(opts[i+2+j*8+4:]) - gotSACKBlocks = append(gotSACKBlocks, header.SACKBlock{ - Start: seqnum.Value(start), - End: seqnum.Value(end), - }) - } - i += sackOptionLen - default: - // We don't recognize this option, just skip over it. - if i+2 > limit { - break - } - l := int(opts[i+1]) - if l < 2 || i+l > limit { - break - } - i += l - } - } - - if !reflect.DeepEqual(gotSACKBlocks, sackBlocks) { - t.Errorf("SACKBlocks are not equal, got: %v, want: %v", gotSACKBlocks, sackBlocks) - } - } -} - -// Payload creates a checker that checks the payload. -func Payload(want []byte) TransportChecker { - return func(t *testing.T, h header.Transport) { - if got := h.Payload(); !reflect.DeepEqual(got, want) { - t.Errorf("Wrong payload, got %v, want %v", got, want) - } - } -} |