// matchTxAndUpdate returns true if the bloom filter matches data within the
// passed transaction, otherwise false is returned. If the filter does match
// the passed transaction, it will also update the filter depending on the bloom
// update flags set via the loaded filter if needed.
//
// This function MUST be called with the filter lock held.
func (bf *Filter) matchTxAndUpdate(tx *dcrutil.Tx) bool {
// Check if the filter matches the hash of the transaction.
// This is useful for finding transactions when they appear in a block.
matched := bf.matches(tx.Sha().Bytes())
// Check if the filter matches any data elements in the public key
// scripts of any of the outputs. When it does, add the outpoint that
// matched so transactions which spend from the matched transaction are
// also included in the filter. This removes the burden of updating the
// filter for this scenario from the client. It is also more efficient
// on the network since it avoids the need for another filteradd message
// from the client and avoids some potential races that could otherwise
// occur.
for i, txOut := range tx.MsgTx().TxOut {
pushedData, err := txscript.PushedData(txOut.PkScript)
if err != nil {
continue
}
for _, data := range pushedData {
if !bf.matches(data) {
continue
}
matched = true
bf.maybeAddOutpoint(txOut.Version, txOut.PkScript, tx.Sha(),
uint32(i), tx.Tree())
break
}
}
// Nothing more to do if a match has already been made.
if matched {
return true
}
// At this point, the transaction and none of the data elements in the
// public key scripts of its outputs matched.
// Check if the filter matches any outpoints this transaction spends or
// any any data elements in the signature scripts of any of the inputs.
for _, txin := range tx.MsgTx().TxIn {
if bf.matchesOutPoint(&txin.PreviousOutPoint) {
return true
}
pushedData, err := txscript.PushedData(txin.SignatureScript)
if err != nil {
continue
}
for _, data := range pushedData {
if bf.matches(data) {
return true
}
}
}
return false
}
// TestPushedData ensured the PushedData function extracts the expected data out
// of various scripts.
func TestPushedData(t *testing.T) {
t.Parallel()
var tests = []struct {
script string
out [][]byte
valid bool
}{
{
"0 IF 0 ELSE 2 ENDIF",
[][]byte{nil, nil},
true,
},
{
"16777216 10000000",
[][]byte{
{0x00, 0x00, 0x00, 0x01}, // 16777216
{0x80, 0x96, 0x98, 0x00}, // 10000000
},
true,
},
{
"DUP HASH160 '17VZNX1SN5NtKa8UQFxwQbFeFc3iqRYhem' EQUALVERIFY CHECKSIG",
[][]byte{
// 17VZNX1SN5NtKa8UQFxwQbFeFc3iqRYhem
{
0x31, 0x37, 0x56, 0x5a, 0x4e, 0x58, 0x31, 0x53, 0x4e, 0x35,
0x4e, 0x74, 0x4b, 0x61, 0x38, 0x55, 0x51, 0x46, 0x78, 0x77,
0x51, 0x62, 0x46, 0x65, 0x46, 0x63, 0x33, 0x69, 0x71, 0x52,
0x59, 0x68, 0x65, 0x6d,
},
},
true,
},
{
"PUSHDATA4 1000 EQUAL",
nil,
false,
},
}
for i, test := range tests {
script := mustParseShortForm(test.script)
data, err := txscript.PushedData(script)
if test.valid && err != nil {
t.Errorf("TestPushedData failed test #%d: %v\n", i, err)
continue
} else if !test.valid && err == nil {
t.Errorf("TestPushedData failed test #%d: test should "+
"be invalid\n", i)
continue
}
if !reflect.DeepEqual(data, test.out) {
t.Errorf("TestPushedData failed test #%d: want: %x "+
"got: %x\n", i, test.out, data)
}
}
}