txscript: add support to re-derive output's PkScript from input

In this commit, we extend the txscript package to support re-deriving
the PkScript of an output by looking at the input's signature
script/witness attempting to spend it. As of this commit, the only
supported types are P2SH, v0 P2WSH, and v0 P2WPKH.

This will serve useful to detect when a particular script has been spent
on-chain.

A set of test vectors has also been added for the supported script types
to ensure its correctness.
This commit is contained in:
Wilmer Paulino 2018-12-04 10:19:58 -08:00
parent 5bda5314ca
commit 0cec774a75
No known key found for this signature in database
GPG key ID: 6DF57B9F9514972F
2 changed files with 700 additions and 0 deletions

260
txscript/pkscript.go Normal file
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package txscript
import (
"crypto/sha256"
"errors"
"fmt"
"github.com/btcsuite/btcd/btcec"
"github.com/btcsuite/btcd/chaincfg"
"github.com/btcsuite/btcd/wire"
"github.com/btcsuite/btcutil"
"golang.org/x/crypto/ripemd160"
)
const (
// pubKeyHashSigScriptLen is the length of a signature script attempting
// to spend a P2PKH script. The only other possible length value is 107
// bytes, due to the signature within it. This length is determined by
// the following:
// 0x47 or 0x48 (71 or 72 byte data push) | <71 or 72 byte sig> |
// 0x21 (33 byte data push) | <33 byte compressed pubkey>
pubKeyHashSigScriptLen = 106
// compressedPubKeyLen is the length in bytes of a compressed public
// key.
compressedPubKeyLen = 33
// pubKeyHashLen is the length of a P2PKH script.
pubKeyHashLen = 25
// witnessV0PubKeyHashLen is the length of a P2WPKH script.
witnessV0PubKeyHashLen = 22
// scriptHashLen is the length of a P2SH script.
scriptHashLen = 23
// witnessV0ScriptHashLen is the length of a P2WSH script.
witnessV0ScriptHashLen = 34
// maxLen is the maximum script length supported by ParsePkScript.
maxLen = witnessV0ScriptHashLen
)
var (
// ErrUnsupportedScriptType is an error returned when we attempt to
// parse/re-compute an output script into a PkScript struct.
ErrUnsupportedScriptType = errors.New("unsupported script type")
)
// PkScript is a wrapper struct around a byte array, allowing it to be used
// as a map index.
type PkScript struct {
// class is the type of the script encoded within the byte array. This
// is used to determine the correct length of the script within the byte
// array.
class ScriptClass
// script is the script contained within a byte array. If the script is
// smaller than the length of the byte array, it will be padded with 0s
// at the end.
script [maxLen]byte
}
// ParsePkScript parses an output script into the PkScript struct.
// ErrUnsupportedScriptType is returned when attempting to parse an unsupported
// script type.
func ParsePkScript(pkScript []byte) (PkScript, error) {
var outputScript PkScript
scriptClass, _, _, err := ExtractPkScriptAddrs(
pkScript, &chaincfg.MainNetParams,
)
if err != nil {
return outputScript, fmt.Errorf("unable to parse script type: "+
"%v", err)
}
if !isSupportedScriptType(scriptClass) {
return outputScript, ErrUnsupportedScriptType
}
outputScript.class = scriptClass
copy(outputScript.script[:], pkScript)
return outputScript, nil
}
// isSupportedScriptType determines whether the script type is supported by the
// PkScript struct.
func isSupportedScriptType(class ScriptClass) bool {
switch class {
case PubKeyHashTy, WitnessV0PubKeyHashTy, ScriptHashTy,
WitnessV0ScriptHashTy:
return true
default:
return false
}
}
// Class returns the script type.
func (s PkScript) Class() ScriptClass {
return s.class
}
// Script returns the script as a byte slice without any padding.
func (s PkScript) Script() []byte {
var script []byte
switch s.class {
case PubKeyHashTy:
script = make([]byte, pubKeyHashLen)
copy(script, s.script[:pubKeyHashLen])
case WitnessV0PubKeyHashTy:
script = make([]byte, witnessV0PubKeyHashLen)
copy(script, s.script[:witnessV0PubKeyHashLen])
case ScriptHashTy:
script = make([]byte, scriptHashLen)
copy(script, s.script[:scriptHashLen])
case WitnessV0ScriptHashTy:
script = make([]byte, witnessV0ScriptHashLen)
copy(script, s.script[:witnessV0ScriptHashLen])
default:
// Unsupported script type.
return nil
}
return script
}
// Address encodes the script into an address for the given chain.
func (s PkScript) Address(chainParams *chaincfg.Params) (btcutil.Address, error) {
_, addrs, _, err := ExtractPkScriptAddrs(s.Script(), chainParams)
if err != nil {
return nil, fmt.Errorf("unable to parse address: %v", err)
}
return addrs[0], nil
}
// String returns a hex-encoded string representation of the script.
func (s PkScript) String() string {
str, _ := DisasmString(s.Script())
return str
}
// ComputePkScript computes the pkScript of an transaction output by looking at
// the transaction input's signature script or witness.
//
// NOTE: Only P2PKH, P2SH, P2WSH, and P2WPKH redeem scripts are supported.
func ComputePkScript(sigScript []byte, witness wire.TxWitness) (PkScript, error) {
var pkScript PkScript
// Ensure that either an input's signature script or a witness was
// provided.
if len(sigScript) == 0 && len(witness) == 0 {
return pkScript, ErrUnsupportedScriptType
}
// We'll start by checking the input's signature script, if provided.
switch {
// If a signature script is provided with a length long enough to
// represent a P2PKH script, then we'll attempt to parse the compressed
// public key from it.
case len(sigScript) == pubKeyHashSigScriptLen ||
len(sigScript) == pubKeyHashSigScriptLen+1:
// The public key should be found as the last part of the
// signature script. We'll attempt to parse it to ensure this is
// a P2PKH redeem script.
pubKey := sigScript[len(sigScript)-compressedPubKeyLen:]
if btcec.IsCompressedPubKey(pubKey) {
pubKeyHash := hash160(pubKey)
script, err := payToPubKeyHashScript(pubKeyHash)
if err != nil {
return pkScript, err
}
pkScript.class = PubKeyHashTy
copy(pkScript.script[:], script)
return pkScript, nil
}
// If it isn't, we'll assume it is a P2SH signature script.
fallthrough
// If we failed to parse a compressed public key from the script in the
// case above, or if the script length is not that of a P2PKH one, and
// our redeem script is only composed of data pushed, we can assume it's
// a P2SH signature script.
case len(sigScript) > 0 && IsPushOnlyScript(sigScript):
// The redeem script will always be the last data push of the
// signature script, so we'll parse the script into opcodes to
// obtain it.
parsedOpcodes, err := parseScript(sigScript)
if err != nil {
return pkScript, err
}
redeemScript := parsedOpcodes[len(parsedOpcodes)-1].data
scriptHash := hash160(redeemScript)
script, err := payToScriptHashScript(scriptHash)
if err != nil {
return pkScript, err
}
pkScript.class = ScriptHashTy
copy(pkScript.script[:], script)
return pkScript, nil
case len(sigScript) > 0:
return pkScript, ErrUnsupportedScriptType
}
// If a witness was provided instead, we'll use the last item of the
// witness stack to determine the proper witness type.
lastWitnessItem := witness[len(witness)-1]
switch {
// If the witness stack has a size of 2 and its last item is a
// compressed public key, then this is a P2WPKH witness.
case len(witness) == 2 && len(lastWitnessItem) == compressedPubKeyLen:
pubKeyHash := hash160(lastWitnessItem)
script, err := payToWitnessPubKeyHashScript(pubKeyHash)
if err != nil {
return pkScript, err
}
pkScript.class = WitnessV0PubKeyHashTy
copy(pkScript.script[:], script)
return pkScript, nil
// For any other witnesses, we'll assume it's a P2WSH witness.
default:
scriptHash := sha256.Sum256(lastWitnessItem)
script, err := payToWitnessScriptHashScript(scriptHash[:])
if err != nil {
return pkScript, err
}
pkScript.class = WitnessV0ScriptHashTy
copy(pkScript.script[:], script)
return pkScript, nil
}
}
// hash160 returns the RIPEMD160 hash of the SHA-256 HASH of the given data.
func hash160(data []byte) []byte {
h := sha256.Sum256(data)
return ripemd160h(h[:])
}
// ripemd160h returns the RIPEMD160 hash of the given data.
func ripemd160h(data []byte) []byte {
h := ripemd160.New()
h.Write(data)
return h.Sum(nil)
}

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txscript/pkscript_test.go Normal file
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package txscript
import (
"bytes"
"testing"
"github.com/btcsuite/btcd/wire"
)
// TestParsePkScript ensures that the supported script types can be parsed
// correctly and re-derived into its raw byte representation.
func TestParsePkScript(t *testing.T) {
t.Parallel()
tests := []struct {
name string
pkScript []byte
valid bool
}{
{
name: "empty output script",
pkScript: []byte{},
valid: false,
},
{
name: "valid P2PKH",
pkScript: []byte{
// OP_DUP
0x76,
// OP_HASH160
0xa9,
// OP_DATA_20
0x14,
// <20-byte pubkey hash>
0xf0, 0x7a, 0xb8, 0xce, 0x72, 0xda, 0x4e, 0x76,
0x0b, 0x74, 0x7d, 0x48, 0xd6, 0x65, 0xec, 0x96,
0xad, 0xf0, 0x24, 0xf5,
// OP_EQUALVERIFY
0x88,
// OP_CHECKSIG
0xac,
},
valid: true,
},
// Invalid P2PKH - same as above but replaced OP_CHECKSIG with
// OP_CHECKSIGVERIFY.
{
name: "invalid P2PKH",
pkScript: []byte{
// OP_DUP
0x76,
// OP_HASH160
0xa9,
// OP_DATA_20
0x14,
// <20-byte pubkey hash>
0xf0, 0x7a, 0xb8, 0xce, 0x72, 0xda, 0x4e, 0x76,
0x0b, 0x74, 0x7d, 0x48, 0xd6, 0x65, 0xec, 0x96,
0xad, 0xf0, 0x24, 0xf5,
// OP_EQUALVERIFY
0x88,
// OP_CHECKSIGVERIFY
0xad,
},
valid: false,
},
{
name: "valid P2SH",
pkScript: []byte{
// OP_HASH160
0xA9,
// OP_DATA_20
0x14,
// <20-byte script hash>
0xec, 0x6f, 0x7a, 0x5a, 0xa8, 0xf2, 0xb1, 0x0c,
0xa5, 0x15, 0x04, 0x52, 0x3a, 0x60, 0xd4, 0x03,
0x06, 0xf6, 0x96, 0xcd,
// OP_EQUAL
0x87,
},
valid: true,
},
// Invalid P2SH - same as above but replaced OP_EQUAL with
// OP_EQUALVERIFY.
{
name: "invalid P2SH",
pkScript: []byte{
// OP_HASH160
0xA9,
// OP_DATA_20
0x14,
// <20-byte script hash>
0xec, 0x6f, 0x7a, 0x5a, 0xa8, 0xf2, 0xb1, 0x0c,
0xa5, 0x15, 0x04, 0x52, 0x3a, 0x60, 0xd4, 0x03,
0x06, 0xf6, 0x96, 0xcd,
// OP_EQUALVERIFY
0x88,
},
valid: false,
},
{
name: "valid v0 P2WSH",
pkScript: []byte{
// OP_0
0x00,
// OP_DATA_32
0x20,
// <32-byte script hash>
0xec, 0x6f, 0x7a, 0x5a, 0xa8, 0xf2, 0xb1, 0x0c,
0xa5, 0x15, 0x04, 0x52, 0x3a, 0x60, 0xd4, 0x03,
0x06, 0xf6, 0x96, 0xcd, 0x06, 0xf6, 0x96, 0xcd,
0x06, 0xf6, 0x96, 0xcd, 0x06, 0xf6, 0x96, 0xcd,
},
valid: true,
},
// Invalid v0 P2WSH - same as above but missing one byte.
{
name: "invalid v0 P2WSH",
pkScript: []byte{
// OP_0
0x00,
// OP_DATA_32
0x20,
// <32-byte script hash>
0xec, 0x6f, 0x7a, 0x5a, 0xa8, 0xf2, 0xb1, 0x0c,
0xa5, 0x15, 0x04, 0x52, 0x3a, 0x60, 0xd4, 0x03,
0x06, 0xf6, 0x96, 0xcd, 0x06, 0xf6, 0x96, 0xcd,
0x06, 0xf6, 0x96, 0xcd, 0x06, 0xf6, 0x96,
},
valid: false,
},
{
name: "valid v0 P2WPKH",
pkScript: []byte{
// OP_0
0x00,
// OP_DATA_20
0x14,
// <20-byte pubkey hash>
0xec, 0x6f, 0x7a, 0x5a, 0xa8, 0xf2, 0xb1, 0x0c,
0xa5, 0x15, 0x04, 0x52, 0x3a, 0x60, 0xd4, 0x03,
0x06, 0xf6, 0x96, 0xcd,
},
valid: true,
},
// Invalid v0 P2WPKH - same as above but missing one byte.
{
name: "invalid v0 P2WPKH",
pkScript: []byte{
// OP_0
0x00,
// OP_DATA_20
0x14,
// <20-byte pubkey hash>
0xec, 0x6f, 0x7a, 0x5a, 0xa8, 0xf2, 0xb1, 0x0c,
0xa5, 0x15, 0x04, 0x52, 0x3a, 0x60, 0xd4, 0x03,
0x06, 0xf6, 0x96,
},
valid: false,
},
}
for _, test := range tests {
t.Run(test.name, func(t *testing.T) {
pkScript, err := ParsePkScript(test.pkScript)
switch {
case err != nil && test.valid:
t.Fatalf("unable to parse valid pkScript=%x: %v",
test.pkScript, err)
case err == nil && !test.valid:
t.Fatalf("successfully parsed invalid pkScript=%x",
test.pkScript)
}
if !test.valid {
return
}
if !bytes.Equal(pkScript.Script(), test.pkScript) {
t.Fatalf("expected to re-derive pkScript=%x, "+
"got pkScript=%x", test.pkScript,
pkScript.Script())
}
})
}
}
// TestComputePkScript ensures that we can correctly re-derive an output's
// pkScript by looking at the input's signature script/witness attempting to
// spend it.
func TestComputePkScript(t *testing.T) {
t.Parallel()
tests := []struct {
name string
sigScript []byte
witness wire.TxWitness
class ScriptClass
pkScript []byte
}{
{
name: "empty sigScript and witness",
sigScript: nil,
witness: nil,
class: NonStandardTy,
pkScript: nil,
},
{
name: "P2PKH sigScript",
sigScript: []byte{
// OP_DATA_71,
0x47,
// <71-byte sig>
0x30, 0x44, 0x02, 0x20, 0x65, 0x92, 0xd8, 0x8e,
0x1d, 0x0a, 0x4a, 0x3c, 0xc5, 0x9f, 0x92, 0xae,
0xfe, 0x62, 0x54, 0x74, 0xa9, 0x4d, 0x13, 0xa5,
0x9f, 0x84, 0x97, 0x78, 0xfc, 0xe7, 0xdf, 0x4b,
0xe0, 0xc2, 0x28, 0xd8, 0x02, 0x20, 0x2d, 0xea,
0x36, 0x96, 0x19, 0x1f, 0xb7, 0x00, 0xc5, 0xa7,
0x7e, 0x22, 0xd9, 0xfb, 0x6b, 0x42, 0x67, 0x42,
0xa4, 0x2c, 0xac, 0xdb, 0x74, 0xa2, 0x7c, 0x43,
0xcd, 0x89, 0xa0, 0xf9, 0x44, 0x54, 0x01,
// OP_DATA_33
0x21,
// <33-byte compressed pubkey>
0x02, 0x7d, 0x56, 0x12, 0x09, 0x75, 0x31, 0xc2,
0x17, 0xfd, 0xd4, 0xd2, 0xe1, 0x7a, 0x35, 0x4b,
0x17, 0xf2, 0x7a, 0xef, 0x30, 0x9f, 0xb2, 0x7f,
0x1f, 0x1f, 0x7b, 0x73, 0x7d, 0x9a, 0x24, 0x49,
0x90,
},
witness: nil,
class: PubKeyHashTy,
pkScript: []byte{
// OP_DUP
0x76,
// OP_HASH160
0xa9,
// OP_DATA_20
0x14,
// <20-byte pubkey hash>
0xf0, 0x7a, 0xb8, 0xce, 0x72, 0xda, 0x4e, 0x76,
0x0b, 0x74, 0x7d, 0x48, 0xd6, 0x65, 0xec, 0x96,
0xad, 0xf0, 0x24, 0xf5,
// OP_EQUALVERIFY
0x88,
// OP_CHECKSIG
0xac,
},
},
{
name: "NP2WPKH sigScript",
// Since this is a NP2PKH output, the sigScript is a
// data push of a serialized v0 P2WPKH script.
sigScript: []byte{
// OP_DATA_16
0x16,
// <22-byte redeem script>
0x00, 0x14, 0x1d, 0x7c, 0xd6, 0xc7, 0x5c, 0x2e,
0x86, 0xf4, 0xcb, 0xf9, 0x8e, 0xae, 0xd2, 0x21,
0xb3, 0x0b, 0xd9, 0xa0, 0xb9, 0x28,
},
// NP2PKH outputs include a witness, but it is not
// needed to reconstruct the pkScript.
witness: nil,
class: ScriptHashTy,
pkScript: []byte{
// OP_HASH160
0xa9,
// OP_DATA_20
0x14,
// <20-byte script hash>
0x90, 0x1c, 0x86, 0x94, 0xc0, 0x3f, 0xaf, 0xd5,
0x52, 0x28, 0x10, 0xe0, 0x33, 0x0f, 0x26, 0xe6,
0x7a, 0x85, 0x33, 0xcd,
// OP_EQUAL
0x87,
},
},
{
name: "P2SH sigScript",
sigScript: []byte{
0x00, 0x49, 0x30, 0x46, 0x02, 0x21, 0x00, 0xda,
0xe6, 0xb6, 0x14, 0x1b, 0xa7, 0x24, 0x4f, 0x54,
0x62, 0xb6, 0x2a, 0x3b, 0x27, 0x59, 0xde, 0xe4,
0x46, 0x76, 0x19, 0x4e, 0x6c, 0x56, 0x8d, 0x5b,
0x1c, 0xda, 0x96, 0x2d, 0x4f, 0x6d, 0x79, 0x02,
0x21, 0x00, 0xa6, 0x6f, 0x60, 0x34, 0x46, 0x09,
0x0a, 0x22, 0x3c, 0xec, 0x30, 0x33, 0xd9, 0x86,
0x24, 0xd2, 0x73, 0xa8, 0x91, 0x55, 0xa5, 0xe6,
0x96, 0x66, 0x0b, 0x6a, 0x50, 0xa3, 0x46, 0x45,
0xbb, 0x67, 0x01, 0x48, 0x30, 0x45, 0x02, 0x21,
0x00, 0xe2, 0x73, 0x49, 0xdb, 0x93, 0x82, 0xe1,
0xf8, 0x8d, 0xae, 0x97, 0x5c, 0x71, 0x19, 0xb7,
0x79, 0xb6, 0xda, 0x43, 0xa8, 0x4f, 0x16, 0x05,
0x87, 0x11, 0x9f, 0xe8, 0x12, 0x1d, 0x85, 0xae,
0xee, 0x02, 0x20, 0x6f, 0x23, 0x2d, 0x0a, 0x7b,
0x4b, 0xfa, 0xcd, 0x56, 0xa0, 0x72, 0xcc, 0x2a,
0x44, 0x81, 0x31, 0xd1, 0x0d, 0x73, 0x35, 0xf9,
0xa7, 0x54, 0x8b, 0xee, 0x1f, 0x70, 0xc5, 0x71,
0x0b, 0x37, 0x9e, 0x01, 0x47, 0x52, 0x21, 0x03,
0xab, 0x11, 0x5d, 0xa6, 0xdf, 0x4f, 0x54, 0x0b,
0xd6, 0xc9, 0xc4, 0xbe, 0x5f, 0xdd, 0xcc, 0x24,
0x58, 0x8e, 0x7c, 0x2c, 0xaf, 0x13, 0x82, 0x28,
0xdd, 0x0f, 0xce, 0x29, 0xfd, 0x65, 0xb8, 0x7c,
0x21, 0x02, 0x15, 0xe8, 0xb7, 0xbf, 0xfe, 0x8d,
0x9b, 0xbd, 0x45, 0x81, 0xf9, 0xc3, 0xb6, 0xf1,
0x6d, 0x67, 0x08, 0x36, 0xc3, 0x0b, 0xb2, 0xe0,
0x3e, 0xfd, 0x9d, 0x41, 0x03, 0xb5, 0x59, 0xeb,
0x67, 0xcd, 0x52, 0xae,
},
witness: nil,
class: ScriptHashTy,
pkScript: []byte{
// OP_HASH160
0xA9,
// OP_DATA_20
0x14,
// <20-byte script hash>
0x12, 0xd6, 0x9c, 0xd3, 0x38, 0xa3, 0x8d, 0x0d,
0x77, 0x83, 0xcf, 0x22, 0x64, 0x97, 0x63, 0x3d,
0x3c, 0x20, 0x79, 0xea,
// OP_EQUAL
0x87,
},
},
// Invalid P2SH (non push-data only script).
{
name: "invalid P2SH sigScript",
sigScript: []byte{0x6b, 0x65, 0x6b}, // kek
witness: nil,
class: NonStandardTy,
pkScript: nil,
},
{
name: "P2WSH witness",
sigScript: nil,
witness: [][]byte{
[]byte{},
// Witness script.
[]byte{
0x21, 0x03, 0x82, 0x62, 0xa6, 0xc6,
0xce, 0xc9, 0x3c, 0x2d, 0x3e, 0xcd,
0x6c, 0x60, 0x72, 0xef, 0xea, 0x86,
0xd0, 0x2f, 0xf8, 0xe3, 0x32, 0x8b,
0xbd, 0x02, 0x42, 0xb2, 0x0a, 0xf3,
0x42, 0x59, 0x90, 0xac, 0xac,
},
},
class: WitnessV0ScriptHashTy,
pkScript: []byte{
// OP_0
0x00,
// OP_DATA_32
0x20,
// <32-byte script hash>
0x01, 0xd5, 0xd9, 0x2e, 0xff, 0xa6, 0xff, 0xba,
0x3e, 0xfa, 0x37, 0x9f, 0x98, 0x30, 0xd0, 0xf7,
0x56, 0x18, 0xb1, 0x33, 0x93, 0x82, 0x71, 0x52,
0xd2, 0x6e, 0x43, 0x09, 0x00, 0x0e, 0x88, 0xb1,
},
},
{
name: "P2WPKH witness",
sigScript: nil,
witness: [][]byte{
// Signature is not needed to re-derive the
// pkScript.
[]byte{},
// Compressed pubkey.
[]byte{
0x03, 0x82, 0x62, 0xa6, 0xc6, 0xce,
0xc9, 0x3c, 0x2d, 0x3e, 0xcd, 0x6c,
0x60, 0x72, 0xef, 0xea, 0x86, 0xd0,
0x2f, 0xf8, 0xe3, 0x32, 0x8b, 0xbd,
0x02, 0x42, 0xb2, 0x0a, 0xf3, 0x42,
0x59, 0x90, 0xac,
},
},
class: WitnessV0PubKeyHashTy,
pkScript: []byte{
// OP_0
0x00,
// OP_DATA_20
0x14,
// <20-byte pubkey hash>
0x1d, 0x7c, 0xd6, 0xc7, 0x5c, 0x2e, 0x86, 0xf4,
0xcb, 0xf9, 0x8e, 0xae, 0xd2, 0x21, 0xb3, 0x0b,
0xd9, 0xa0, 0xb9, 0x28,
},
},
// Invalid v0 P2WPKH - same as above but missing a byte on the
// public key.
{
name: "invalid P2WPKH witness",
sigScript: nil,
witness: [][]byte{
// Signature is not needed to re-derive the
// pkScript.
[]byte{},
// Malformed compressed pubkey.
[]byte{
0x03, 0x82, 0x62, 0xa6, 0xc6, 0xce,
0xc9, 0x3c, 0x2d, 0x3e, 0xcd, 0x6c,
0x60, 0x72, 0xef, 0xea, 0x86, 0xd0,
0x2f, 0xf8, 0xe3, 0x32, 0x8b, 0xbd,
0x02, 0x42, 0xb2, 0x0a, 0xf3, 0x42,
0x59, 0x90,
},
},
class: WitnessV0PubKeyHashTy,
pkScript: nil,
},
}
for _, test := range tests {
t.Run(test.name, func(t *testing.T) {
valid := test.pkScript != nil
pkScript, err := ComputePkScript(
test.sigScript, test.witness,
)
if err != nil && valid {
t.Fatalf("unable to compute pkScript: %v", err)
}
if !valid {
return
}
if pkScript.Class() != test.class {
t.Fatalf("expected pkScript of type %v, got %v",
test.class, pkScript.Class())
}
if !bytes.Equal(pkScript.Script(), test.pkScript) {
t.Fatalf("expected pkScript=%x, got pkScript=%x",
test.pkScript, pkScript.Script())
}
})
}
}