// TestMerkleBlockOverflowErrors performs tests to ensure encoding and decoding
// merkle blocks that are intentionally crafted to use large values for the
// number of hashes and flags are handled properly. This could otherwise
// potentially be used as an attack vector.
func TestMerkleBlockOverflowErrors(t *testing.T) {
// Use protocol version 70001 specifically here instead of the latest
// protocol version because the test data is using bytes encoded with
// that version.
pver := uint32(70001)
// Create bytes for a merkle block that claims to have more than the max
// allowed tx hashes.
var buf bytes.Buffer
wire.TstWriteVarInt(&buf, pver, wire.MaxTxPerBlock+1)
numHashesOffset := 84
exceedMaxHashes := make([]byte, numHashesOffset)
copy(exceedMaxHashes, merkleBlockOneBytes[:numHashesOffset])
exceedMaxHashes = append(exceedMaxHashes, buf.Bytes()...)
// Create bytes for a merkle block that claims to have more than the max
// allowed flag bytes.
buf.Reset()
wire.TstWriteVarInt(&buf, pver, wire.MaxFlagsPerMerkleBlock+1)
numFlagBytesOffset := 117
exceedMaxFlagBytes := make([]byte, numFlagBytesOffset)
copy(exceedMaxFlagBytes, merkleBlockOneBytes[:numFlagBytesOffset])
exceedMaxFlagBytes = append(exceedMaxFlagBytes, buf.Bytes()...)
tests := []struct {
buf []byte // Wire encoding
pver uint32 // Protocol version for wire encoding
err error // Expected error
}{
// Block that claims to have more than max allowed hashes.
{exceedMaxHashes, pver, &wire.MessageError{}},
// Block that claims to have more than max allowed flag bytes.
{exceedMaxFlagBytes, pver, &wire.MessageError{}},
}
t.Logf("Running %d tests", len(tests))
for i, test := range tests {
// Decode from wire format.
var msg wire.MsgMerkleBlock
r := bytes.NewReader(test.buf)
err := msg.BtcDecode(r, test.pver)
if reflect.TypeOf(err) != reflect.TypeOf(test.err) {
t.Errorf("BtcDecode #%d wrong error got: %v, want: %v",
i, err, reflect.TypeOf(test.err))
continue
}
}
}
// TestVarIntWireErrors performs negative tests against wire encode and decode
// of variable length integers to confirm error paths work correctly.
func TestVarIntWireErrors(t *testing.T) {
pver := wire.ProtocolVersion
tests := []struct {
in uint64 // Value to encode
buf []byte // Wire encoding
pver uint32 // Protocol version for wire encoding
max int // Max size of fixed buffer to induce errors
writeErr error // Expected write error
readErr error // Expected read error
}{
// Force errors on discriminant.
{0, []byte{0x00}, pver, 0, io.ErrShortWrite, io.EOF},
// Force errors on 2-byte read/write.
{0xfd, []byte{0xfd}, pver, 2, io.ErrShortWrite, io.ErrUnexpectedEOF},
// Force errors on 4-byte read/write.
{0x10000, []byte{0xfe}, pver, 2, io.ErrShortWrite, io.ErrUnexpectedEOF},
// Force errors on 8-byte read/write.
{0x100000000, []byte{0xff}, pver, 2, io.ErrShortWrite, io.ErrUnexpectedEOF},
}
t.Logf("Running %d tests", len(tests))
for i, test := range tests {
// Encode to wire format.
w := newFixedWriter(test.max)
err := wire.TstWriteVarInt(w, test.pver, test.in)
if err != test.writeErr {
t.Errorf("writeVarInt #%d wrong error got: %v, want: %v",
i, err, test.writeErr)
continue
}
// Decode from wire format.
r := newFixedReader(test.max, test.buf)
_, err = wire.TstReadVarInt(r, test.pver)
if err != test.readErr {
t.Errorf("readVarInt #%d wrong error got: %v, want: %v",
i, err, test.readErr)
continue
}
}
}
// TestVarIntWire tests wire encode and decode for variable length integers.
func TestVarIntWire(t *testing.T) {
pver := wire.ProtocolVersion
tests := []struct {
in uint64 // Value to encode
out uint64 // Expected decoded value
buf []byte // Wire encoding
pver uint32 // Protocol version for wire encoding
}{
// Latest protocol version.
// Single byte
{0, 0, []byte{0x00}, pver},
// Max single byte
{0xfc, 0xfc, []byte{0xfc}, pver},
// Min 2-byte
{0xfd, 0xfd, []byte{0xfd, 0x0fd, 0x00}, pver},
// Max 2-byte
{0xffff, 0xffff, []byte{0xfd, 0xff, 0xff}, pver},
// Min 4-byte
{0x10000, 0x10000, []byte{0xfe, 0x00, 0x00, 0x01, 0x00}, pver},
// Max 4-byte
{0xffffffff, 0xffffffff, []byte{0xfe, 0xff, 0xff, 0xff, 0xff}, pver},
// Min 8-byte
{
0x100000000, 0x100000000,
[]byte{0xff, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00},
pver,
},
// Max 8-byte
{
0xffffffffffffffff, 0xffffffffffffffff,
[]byte{0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff},
pver,
},
}
t.Logf("Running %d tests", len(tests))
for i, test := range tests {
// Encode to wire format.
var buf bytes.Buffer
err := wire.TstWriteVarInt(&buf, test.pver, test.in)
if err != nil {
t.Errorf("writeVarInt #%d error %v", i, err)
continue
}
if !bytes.Equal(buf.Bytes(), test.buf) {
t.Errorf("writeVarInt #%d\n got: %s want: %s", i,
spew.Sdump(buf.Bytes()), spew.Sdump(test.buf))
continue
}
// Decode from wire format.
rbuf := bytes.NewReader(test.buf)
val, err := wire.TstReadVarInt(rbuf, test.pver)
if err != nil {
t.Errorf("readVarInt #%d error %v", i, err)
continue
}
if val != test.out {
t.Errorf("readVarInt #%d\n got: %d want: %d", i,
val, test.out)
continue
}
}
}
// TestVersionWireErrors performs negative tests against wire encode and
// decode of MsgGetHeaders to confirm error paths work correctly.
func TestVersionWireErrors(t *testing.T) {
// Use protocol version 60002 specifically here instead of the latest
// because the test data is using bytes encoded with that protocol
// version.
pver := uint32(60002)
wireErr := &wire.MessageError{}
// Ensure calling MsgVersion.BtcDecode with a non *bytes.Buffer returns
// error.
fr := newFixedReader(0, []byte{})
if err := baseVersion.BtcDecode(fr, pver); err == nil {
t.Errorf("Did not received error when calling " +
"MsgVersion.BtcDecode with non *bytes.Buffer")
}
// Copy the base version and change the user agent to exceed max limits.
bvc := *baseVersion
exceedUAVer := &bvc
newUA := "/" + strings.Repeat("t", wire.MaxUserAgentLen-8+1) + ":0.0.1/"
exceedUAVer.UserAgent = newUA
// Encode the new UA length as a varint.
var newUAVarIntBuf bytes.Buffer
err := wire.TstWriteVarInt(&newUAVarIntBuf, pver, uint64(len(newUA)))
if err != nil {
t.Errorf("writeVarInt: error %v", err)
}
// Make a new buffer big enough to hold the base version plus the new
// bytes for the bigger varint to hold the new size of the user agent
// and the new user agent string. Then stich it all together.
newLen := len(baseVersionEncoded) - len(baseVersion.UserAgent)
newLen = newLen + len(newUAVarIntBuf.Bytes()) - 1 + len(newUA)
exceedUAVerEncoded := make([]byte, newLen)
copy(exceedUAVerEncoded, baseVersionEncoded[0:80])
copy(exceedUAVerEncoded[80:], newUAVarIntBuf.Bytes())
copy(exceedUAVerEncoded[83:], []byte(newUA))
copy(exceedUAVerEncoded[83+len(newUA):], baseVersionEncoded[97:100])
tests := []struct {
in *wire.MsgVersion // Value to encode
buf []byte // Wire encoding
pver uint32 // Protocol version for wire encoding
max int // Max size of fixed buffer to induce errors
writeErr error // Expected write error
readErr error // Expected read error
}{
// Force error in protocol version.
{baseVersion, baseVersionEncoded, pver, 0, io.ErrShortWrite, io.EOF},
// Force error in services.
{baseVersion, baseVersionEncoded, pver, 4, io.ErrShortWrite, io.EOF},
// Force error in timestamp.
{baseVersion, baseVersionEncoded, pver, 12, io.ErrShortWrite, io.EOF},
// Force error in remote address.
{baseVersion, baseVersionEncoded, pver, 20, io.ErrShortWrite, io.EOF},
// Force error in local address.
{baseVersion, baseVersionEncoded, pver, 47, io.ErrShortWrite, io.ErrUnexpectedEOF},
// Force error in nonce.
{baseVersion, baseVersionEncoded, pver, 73, io.ErrShortWrite, io.ErrUnexpectedEOF},
// Force error in user agent length.
{baseVersion, baseVersionEncoded, pver, 81, io.ErrShortWrite, io.EOF},
// Force error in user agent.
{baseVersion, baseVersionEncoded, pver, 82, io.ErrShortWrite, io.ErrUnexpectedEOF},
// Force error in last block.
{baseVersion, baseVersionEncoded, pver, 98, io.ErrShortWrite, io.ErrUnexpectedEOF},
// Force error in relay tx - no read error should happen since
// it's optional.
{
baseVersionBIP0037, baseVersionBIP0037Encoded,
wire.BIP0037Version, 101, io.ErrShortWrite, nil,
},
// Force error due to user agent too big
{exceedUAVer, exceedUAVerEncoded, pver, newLen, wireErr, wireErr},
}
t.Logf("Running %d tests", len(tests))
for i, test := range tests {
// Encode to wire format.
w := newFixedWriter(test.max)
err := test.in.BtcEncode(w, test.pver)
if reflect.TypeOf(err) != reflect.TypeOf(test.writeErr) {
t.Errorf("BtcEncode #%d wrong error got: %v, want: %v",
i, err, test.writeErr)
continue
}
// For errors which are not of type wire.MessageError, check
// them for equality.
if _, ok := err.(*wire.MessageError); !ok {
if err != test.writeErr {
t.Errorf("BtcEncode #%d wrong error got: %v, "+
"want: %v", i, err, test.writeErr)
continue
}
}
// Decode from wire format.
var msg wire.MsgVersion
buf := bytes.NewBuffer(test.buf[0:test.max])
err = msg.BtcDecode(buf, test.pver)
if reflect.TypeOf(err) != reflect.TypeOf(test.readErr) {
t.Errorf("BtcDecode #%d wrong error got: %v, want: %v",
i, err, test.readErr)
continue
}
// For errors which are not of type wire.MessageError, check
// them for equality.
if _, ok := err.(*wire.MessageError); !ok {
if err != test.readErr {
t.Errorf("BtcDecode #%d wrong error got: %v, "+
"want: %v", i, err, test.readErr)
continue
}
}
}
}