Skip to content

Commit

Permalink
read: fix script matching
Browse files Browse the repository at this point in the history
  • Loading branch information
@tuxcanfly
tuxcanfly committed Mar 4, 2023
1 parent 2f86721 commit 70fbb90
Show file tree
Hide file tree
Showing 3 changed files with 81 additions and 30 deletions.
10 changes: 10 additions & 0 deletions go.mod
View file
Original file line number Diff line number Diff line change
Expand Up @@ -10,11 +10,21 @@ require (
)

require (
github.com/aead/siphash v1.0.1 // indirect
github.com/btcsuite/btclog v0.0.0-20170628155309-84c8d2346e9f // indirect
github.com/btcsuite/go-socks v0.0.0-20170105172521-4720035b7bfd // indirect
github.com/btcsuite/websocket v0.0.0-20150119174127-31079b680792 // indirect
github.com/btcsuite/winsvc v1.0.0 // indirect
github.com/davecgh/go-spew v1.1.1 // indirect
github.com/decred/dcrd/crypto/blake256 v1.0.0 // indirect
github.com/decred/dcrd/dcrec/secp256k1/v4 v4.0.1 // indirect
github.com/decred/dcrd/lru v1.0.0 // indirect
github.com/golang/snappy v0.0.4 // indirect
github.com/jessevdk/go-flags v1.4.0 // indirect
github.com/jrick/logrotate v1.0.0 // indirect
github.com/kkdai/bstream v0.0.0-20161212061736-f391b8402d23 // indirect
github.com/rollkit/btcd v0.0.0-20230304003258-065fdfb84b46 // indirect
github.com/syndtr/goleveldb v1.0.1-0.20210819022825-2ae1ddf74ef7 // indirect
golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9 // indirect
golang.org/x/sys v0.0.0-20200814200057-3d37ad5750ed // indirect
)
10 changes: 10 additions & 0 deletions go.sum
View file
Original file line number Diff line number Diff line change
@@ -1,3 +1,4 @@
github.com/aead/siphash v1.0.1 h1:FwHfE/T45KPKYuuSAKyyvE+oPWcaQ+CUmFW0bPlM+kg=
github.com/aead/siphash v1.0.1/go.mod h1:Nywa3cDsYNNK3gaciGTWPwHt0wlpNV15vwmswBAUSII=
github.com/btcsuite/btcd v0.20.1-beta/go.mod h1:wVuoA8VJLEcwgqHBwHmzLRazpKxTv13Px/pDuV7OomQ=
github.com/btcsuite/btcd v0.22.0-beta.0.20220111032746-97732e52810c/go.mod h1:tjmYdS6MLJ5/s0Fj4DbLgSbDHbEqLJrtnHecBFkdz5M=
Expand Down Expand Up @@ -25,6 +26,7 @@ github.com/btcsuite/snappy-go v0.0.0-20151229074030-0bdef8d06723/go.mod h1:8woku
github.com/btcsuite/snappy-go v1.0.0/go.mod h1:8woku9dyThutzjeg+3xrA5iCpBRH8XEEg3lh6TiUghc=
github.com/btcsuite/websocket v0.0.0-20150119174127-31079b680792 h1:R8vQdOQdZ9Y3SkEwmHoWBmX1DNXhXZqlTpq6s4tyJGc=
github.com/btcsuite/websocket v0.0.0-20150119174127-31079b680792/go.mod h1:ghJtEyQwv5/p4Mg4C0fgbePVuGr935/5ddU9Z3TmDRY=
github.com/btcsuite/winsvc v1.0.0 h1:J9B4L7e3oqhXOcm+2IuNApwzQec85lE+QaikUcCs+dk=
github.com/btcsuite/winsvc v1.0.0/go.mod h1:jsenWakMcC0zFBFurPLEAyrnc/teJEM1O46fmI40EZs=
github.com/davecgh/go-spew v0.0.0-20171005155431-ecdeabc65495/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
Expand All @@ -34,6 +36,7 @@ github.com/decred/dcrd/crypto/blake256 v1.0.0 h1:/8DMNYp9SGi5f0w7uCm6d6M4OU2rGFK
github.com/decred/dcrd/crypto/blake256 v1.0.0/go.mod h1:sQl2p6Y26YV+ZOcSTP6thNdn47hh8kt6rqSlvmrXFAc=
github.com/decred/dcrd/dcrec/secp256k1/v4 v4.0.1 h1:YLtO71vCjJRCBcrPMtQ9nqBsqpA1m5sE92cU+pd5Mcc=
github.com/decred/dcrd/dcrec/secp256k1/v4 v4.0.1/go.mod h1:hyedUtir6IdtD/7lIxGeCxkaw7y45JueMRL4DIyJDKs=
github.com/decred/dcrd/lru v1.0.0 h1:Kbsb1SFDsIlaupWPwsPp+dkxiBY1frcS07PCPgotKz8=
github.com/decred/dcrd/lru v1.0.0/go.mod h1:mxKOwFd7lFjN2GZYsiz/ecgqR6kkYAl+0pz0tEMk218=
github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
github.com/fsnotify/fsnotify v1.4.9/go.mod h1:znqG4EE+3YCdAaPaxE2ZRY/06pZUdp0tY4IgpuI1SZQ=
Expand All @@ -44,14 +47,18 @@ github.com/golang/protobuf v1.4.0-rc.2/go.mod h1:LlEzMj4AhA7rCAGe4KMBDvJI+AwstrU
github.com/golang/protobuf v1.4.0-rc.4.0.20200313231945-b860323f09d0/go.mod h1:WU3c8KckQ9AFe+yFwt9sWVRKCVIyN9cPHBJSNnbL67w=
github.com/golang/protobuf v1.4.0/go.mod h1:jodUvKwWbYaEsadDk5Fwe5c77LiNKVO9IDvqG2KuDX0=
github.com/golang/protobuf v1.4.2/go.mod h1:oDoupMAO8OvCJWAcko0GGGIgR6R6ocIYbsSw735rRwI=
github.com/golang/snappy v0.0.4 h1:yAGX7huGHXlcLOEtBnF4w7FQwA26wojNCwOYAEhLjQM=
github.com/golang/snappy v0.0.4/go.mod h1:/XxbfmMg8lxefKM7IXC3fBNl/7bRcc72aCRzEWrmP2Q=
github.com/google/go-cmp v0.3.0/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=
github.com/google/go-cmp v0.3.1/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=
github.com/google/go-cmp v0.4.0/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
github.com/hpcloud/tail v1.0.0/go.mod h1:ab1qPbhIpdTxEkNHXyeSf5vhxWSCs/tWer42PpOxQnU=
github.com/jessevdk/go-flags v0.0.0-20141203071132-1679536dcc89/go.mod h1:4FA24M0QyGHXBuZZK/XkWh8h0e1EYbRYJSGM75WSRxI=
github.com/jessevdk/go-flags v1.4.0 h1:4IU2WS7AumrZ/40jfhf4QVDMsQwqA7VEHozFRrGARJA=
github.com/jessevdk/go-flags v1.4.0/go.mod h1:4FA24M0QyGHXBuZZK/XkWh8h0e1EYbRYJSGM75WSRxI=
github.com/jrick/logrotate v1.0.0 h1:lQ1bL/n9mBNeIXoTUoYRlK4dHuNJVofX9oWqBtPnSzI=
github.com/jrick/logrotate v1.0.0/go.mod h1:LNinyqDIJnpAur+b8yyulnQw/wDuN1+BYKlTRt3OuAQ=
github.com/kkdai/bstream v0.0.0-20161212061736-f391b8402d23 h1:FOOIBWrEkLgmlgGfMuZT83xIwfPDxEI2OHu6xUmJMFE=
github.com/kkdai/bstream v0.0.0-20161212061736-f391b8402d23/go.mod h1:J+Gs4SYgM6CZQHDETBtE9HaSEkGmuNXF86RwHhHUvq4=
github.com/nxadm/tail v1.4.4/go.mod h1:kenIhsEOeOJmVchQTgglprH7qJGnHDVpk1VPCcaMI8A=
github.com/onsi/ginkgo v1.6.0/go.mod h1:lLunBs/Ym6LB5Z9jYTR76FiuTmxDTDusOGeTQH+WWjE=
Expand All @@ -64,9 +71,12 @@ github.com/onsi/gomega v1.7.1/go.mod h1:XdKZgCCFLUoM/7CFJVPcG8C1xQ1AJ0vpAezJrB7J
github.com/onsi/gomega v1.10.1/go.mod h1:iN09h71vgCQne3DLsj+A5owkum+a2tYe+TOCB1ybHNo=
github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
github.com/rollkit/btcd v0.0.0-20230304003258-065fdfb84b46 h1:Svr3WAt5xHdE+JgoS5r7Z+aSMhxtNvnHPItWsrlEXAY=
github.com/rollkit/btcd v0.0.0-20230304003258-065fdfb84b46/go.mod h1:FewIyVo3jCTveMYfXOJDGhUNTA6MbxH6pBJdaW/cDro=
github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
github.com/stretchr/testify v1.7.0 h1:nwc3DEeHmmLAfoZucVR881uASk0Mfjw8xYJ99tb5CcY=
github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
github.com/syndtr/goleveldb v1.0.1-0.20210819022825-2ae1ddf74ef7 h1:epCh84lMvA70Z7CTTCmYQn2CKbY8j86K7/FAIr141uY=
github.com/syndtr/goleveldb v1.0.1-0.20210819022825-2ae1ddf74ef7/go.mod h1:q4W45IWZaF22tdD+VEXcAWRA037jwmWEB5VWYORlTpc=
golang.org/x/crypto v0.0.0-20170930174604-9419663f5a44/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=
golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
Expand Down
91 changes: 61 additions & 30 deletions relayer.go
View file
Original file line number Diff line number Diff line change
Expand Up @@ -287,22 +287,14 @@ func (r Relayer) ReadTransaction(hash *chainhash.Hash) ([]byte, error) {
return nil, err
}
if len(tx.MsgTx().TxIn[0].Witness) > 1 {
// FIXME: UGLY HACK
// ideally we should template match the script and extract
// see: txscript.ExtractAtomicSwapDataPushes
witness := tx.MsgTx().TxIn[0].Witness[1]
start := bytes.Index(witness, PROTOCOL_ID)
// script template:
// < --------- 35 bytes --------->
// OP_FALSE OP_IF + "roll" marker + <data> + canonical int + 32 bytes pubkey + OP_CHECKSIG
// ^ ^
// start ------------ ^
// end -------------------------------------
if start > 0 && len(witness) > start+35 {
end := len(witness) - 35
if end > start {
return witness[start+4 : end], nil
}
pushData, err := ExtractPushData(0, witness)
if err != nil {
return nil, err
}
// skip PROTOCOL_ID
if pushData != nil && bytes.HasPrefix(pushData, PROTOCOL_ID) {
return pushData[4:], nil
}
}
return nil, nil
Expand All @@ -321,22 +313,14 @@ func (r Relayer) Read(height uint64) ([][]byte, error) {
var data [][]byte
for _, tx := range block.Transactions {
if len(tx.TxIn[0].Witness) > 1 {
// FIXME: UGLY HACK
// ideally we should template match the script and extract
// see: txscript.ExtractAtomicSwapDataPushes
witness := tx.TxIn[0].Witness[1]
start := bytes.Index(witness, PROTOCOL_ID)
// script template:
// < --------- 35 bytes --------->
// OP_FALSE OP_IF + "roll" marker + <data> + canonical int + 32 bytes pubkey + OP_CHECKSIG
// ^ ^
// start ------------ ^
// end -------------------------------------
if start > 0 && len(witness) > start+35 {
end := len(witness) - 35
if end > start {
data = append(data, witness[start+4:end])
}
pushData, err := ExtractPushData(0, witness)
if err != nil {
return nil, err
}
// skip PROTOCOL_ID
if pushData != nil && bytes.HasPrefix(pushData, PROTOCOL_ID) {
data = append(data, pushData[4:])
}
}
}
Expand All @@ -359,3 +343,50 @@ func (r Relayer) Write(data []byte) (*chainhash.Hash, error) {
}
return hash, nil
}

func ExtractPushData(version uint16, pkScript []byte) ([]byte, error) {
type templateMatch struct {
expectPushData bool
maxPushDatas int
opcode byte
extractedData []byte
}
var template = [6]templateMatch{
{opcode: txscript.OP_FALSE},
{opcode: txscript.OP_IF},
{expectPushData: true, maxPushDatas: 10},
{opcode: txscript.OP_ENDIF},
{expectPushData: true, maxPushDatas: 1},
{opcode: txscript.OP_CHECKSIG},
}

var templateOffset int
tokenizer := txscript.MakeScriptTokenizer(version, pkScript)
out:
for tokenizer.Next() {
// Not a rollkit script if it has more opcodes than expected in the
// template.
if templateOffset >= len(template) {
return nil, nil
}

op := tokenizer.Opcode()
tplEntry := &template[templateOffset]
if tplEntry.expectPushData {
for i := 0; i < tplEntry.maxPushDatas; i++ {
data := tokenizer.Data()
if data == nil {
break out
}
tplEntry.extractedData = append(tplEntry.extractedData, data...)
tokenizer.Next()
}
} else if op != tplEntry.opcode {
return nil, nil
}

templateOffset++
}
// TODO: skipping err checks
return template[2].extractedData, nil
}

0 comments on commit 70fbb90

Please sign in to comment.