// createCoinbaseTx returns a coinbase transaction paying an appropriate subsidy
// based on the passed block height to the provided address. When the address
// is nil, the coinbase transaction will instead be redeemable by anyone.
//
// See the comment for NewBlockTemplate for more information about why the nil
// address handling is useful.
func createCoinbaseTx(coinbaseScript []byte, nextBlockHeight int64, addr btcutil.Address) (*btcutil.Tx, error) {
// Create the script to pay to the provided payment address if one was
// specified. Otherwise create a script that allows the coinbase to be
// redeemable by anyone.
var pkScript []byte
if addr != nil {
var err error
pkScript, err = btcscript.PayToAddrScript(addr)
if err != nil {
return nil, err
}
} else {
scriptBuilder := btcscript.NewScriptBuilder()
pkScript = scriptBuilder.AddOp(btcscript.OP_TRUE).Script()
}
tx := btcwire.NewMsgTx()
tx.AddTxIn(&btcwire.TxIn{
// Coinbase transactions have no inputs, so previous outpoint is
// zero hash and max index.
PreviousOutPoint: *btcwire.NewOutPoint(&btcwire.ShaHash{},
btcwire.MaxPrevOutIndex),
SignatureScript: coinbaseScript,
Sequence: btcwire.MaxTxInSequenceNum,
})
tx.AddTxOut(&btcwire.TxOut{
Value: btcchain.CalcBlockSubsidy(nextBlockHeight,
activeNetParams.Params),
PkScript: pkScript,
})
return btcutil.NewTx(tx), nil
}
// TestScriptBuilderAddInt64 tests that pushing signed integers to a script via
// the ScriptBuilder API works as expected.
func TestScriptBuilderAddInt64(t *testing.T) {
tests := []struct {
name string
val int64
expected []byte
}{
{name: "push -1", val: -1, expected: []byte{btcscript.OP_1NEGATE}},
{name: "push small int 0", val: 0, expected: []byte{btcscript.OP_0}},
{name: "push small int 1", val: 1, expected: []byte{btcscript.OP_1}},
{name: "push small int 2", val: 2, expected: []byte{btcscript.OP_2}},
{name: "push small int 3", val: 3, expected: []byte{btcscript.OP_3}},
{name: "push small int 4", val: 4, expected: []byte{btcscript.OP_4}},
{name: "push small int 5", val: 5, expected: []byte{btcscript.OP_5}},
{name: "push small int 6", val: 6, expected: []byte{btcscript.OP_6}},
{name: "push small int 7", val: 7, expected: []byte{btcscript.OP_7}},
{name: "push small int 8", val: 8, expected: []byte{btcscript.OP_8}},
{name: "push small int 9", val: 9, expected: []byte{btcscript.OP_9}},
{name: "push small int 10", val: 10, expected: []byte{btcscript.OP_10}},
{name: "push small int 11", val: 11, expected: []byte{btcscript.OP_11}},
{name: "push small int 12", val: 12, expected: []byte{btcscript.OP_12}},
{name: "push small int 13", val: 13, expected: []byte{btcscript.OP_13}},
{name: "push small int 14", val: 14, expected: []byte{btcscript.OP_14}},
{name: "push small int 15", val: 15, expected: []byte{btcscript.OP_15}},
{name: "push small int 16", val: 16, expected: []byte{btcscript.OP_16}},
{name: "push 17", val: 17, expected: []byte{btcscript.OP_DATA_1, 0x11}},
{name: "push 65", val: 65, expected: []byte{btcscript.OP_DATA_1, 0x41}},
{name: "push 127", val: 127, expected: []byte{btcscript.OP_DATA_1, 0x7f}},
{name: "push 128", val: 128, expected: []byte{btcscript.OP_DATA_2, 0x80, 0}},
{name: "push 255", val: 255, expected: []byte{btcscript.OP_DATA_2, 0xff, 0}},
{name: "push 256", val: 256, expected: []byte{btcscript.OP_DATA_2, 0, 0x01}},
{name: "push 32767", val: 32767, expected: []byte{btcscript.OP_DATA_2, 0xff, 0x7f}},
{name: "push 32768", val: 32768, expected: []byte{btcscript.OP_DATA_3, 0, 0x80, 0}},
{name: "push -2", val: -2, expected: []byte{btcscript.OP_DATA_1, 0x82}},
{name: "push -3", val: -3, expected: []byte{btcscript.OP_DATA_1, 0x83}},
{name: "push -4", val: -4, expected: []byte{btcscript.OP_DATA_1, 0x84}},
{name: "push -5", val: -5, expected: []byte{btcscript.OP_DATA_1, 0x85}},
{name: "push -17", val: -17, expected: []byte{btcscript.OP_DATA_1, 0x91}},
{name: "push -65", val: -65, expected: []byte{btcscript.OP_DATA_1, 0xc1}},
{name: "push -127", val: -127, expected: []byte{btcscript.OP_DATA_1, 0xff}},
{name: "push -128", val: -128, expected: []byte{btcscript.OP_DATA_2, 0x80, 0x80}},
{name: "push -255", val: -255, expected: []byte{btcscript.OP_DATA_2, 0xff, 0x80}},
{name: "push -256", val: -256, expected: []byte{btcscript.OP_DATA_2, 0x00, 0x81}},
{name: "push -32767", val: -32767, expected: []byte{btcscript.OP_DATA_2, 0xff, 0xff}},
{name: "push -32768", val: -32768, expected: []byte{btcscript.OP_DATA_3, 0x00, 0x80, 0x80}},
}
builder := btcscript.NewScriptBuilder()
t.Logf("Running %d tests", len(tests))
for i, test := range tests {
builder.Reset().AddInt64(test.val)
result := builder.Script()
if !bytes.Equal(result, test.expected) {
t.Errorf("ScriptBuilder.AddInt64 #%d (%s) wrong result\n"+
"got: %x\nwant: %x", i, test.name, result,
test.expected)
continue
}
}
}
func makeScriptPubKey(toAddr string) ([]byte, error) {
addr, err := btcutil.DecodeAddress(toAddr, &btcnet.MainNetParams)
if err != nil {
return nil, err
}
log.Println("script addr:", hex.EncodeToString(addr.ScriptAddress()))
builder := btcscript.NewScriptBuilder()
builder.AddOp(btcscript.OP_DUP).AddOp(btcscript.OP_HASH160)
builder.AddData(addr.ScriptAddress())
builder.AddOp(btcscript.OP_EQUALVERIFY).AddOp(btcscript.OP_CHECKSIG)
//script := "76" + "a9" + "14" + hex.EncodeToString(addr.ScriptAddress()) + "88" + "ac"
return builder.Script(), nil
}
func (ndB *NullDataBuilder) Build() (*btcwire.MsgTx, error) {
utxo, err := specificUnspent(ndB.SatNeeded(), ndB.Params)
if err != nil {
return nil, err
}
msgtx := btcwire.NewMsgTx()
if len(ndB.Data) > 40 {
return nil, errors.New("Data is too long to make this a standard tx.")
}
// OP Return output
retbuilder := btcscript.NewScriptBuilder().AddOp(btcscript.OP_RETURN).AddData(ndB.Data)
op_return := btcwire.NewTxOut(0, retbuilder.Script())
msgtx.AddTxOut(op_return)
if ndB.Change {
// change ouput
addr, _ := newAddr(ndB.Params.Client)
change, ok := changeOutput(ndB.SatNeeded()-ndB.Params.Fee, ndB.Params.DustAmnt, addr)
if !ok {
return nil, errors.New("Not enough for change")
}
msgtx.AddTxOut(change)
}
// funding input
txin := btcwire.NewTxIn(utxo.OutPoint, []byte{})
msgtx.AddTxIn(txin)
// sign msgtx
privkey := utxo.Wif.PrivKey
scriptSig, err := btcscript.SignatureScript(msgtx, 0, utxo.TxOut.PkScript, btcscript.SigHashAll, privkey, true)
if err != nil {
return nil, err
}
txin.SignatureScript = scriptSig
return msgtx, nil
}
// TestScriptBuilderAddOp tests that pushing opcodes to a script via the
// ScriptBuilder API works as expected.
func TestScriptBuilderAddOp(t *testing.T) {
tests := []struct {
name string
opcodes []byte
expected []byte
}{
{
name: "push OP_0",
opcodes: []byte{btcscript.OP_0},
expected: []byte{btcscript.OP_0},
},
{
name: "push OP_1 OP_2",
opcodes: []byte{btcscript.OP_1, btcscript.OP_2},
expected: []byte{btcscript.OP_1, btcscript.OP_2},
},
{
name: "push OP_HASH160 OP_EQUAL",
opcodes: []byte{btcscript.OP_HASH160, btcscript.OP_EQUAL},
expected: []byte{btcscript.OP_HASH160, btcscript.OP_EQUAL},
},
}
builder := btcscript.NewScriptBuilder()
t.Logf("Running %d tests", len(tests))
for i, test := range tests {
builder.Reset()
for _, opcode := range test.opcodes {
builder.AddOp(opcode)
}
result := builder.Script()
if !bytes.Equal(result, test.expected) {
t.Errorf("ScriptBuilder.AddOp #%d (%s) wrong result\n"+
"got: %x\nwant: %x", i, test.name, result,
test.expected)
continue
}
}
}
// TODO This will add multisig Txouts to the unspent set be AWARE
func (msB *MultiSigBuilder) Build() (*btcwire.MsgTx, error) {
utxo, err := specificUnspent(msB.SatNeeded(), msB.Params)
if err != nil {
return nil, err
}
msgtx := btcwire.NewMsgTx()
txin := btcwire.NewTxIn(utxo.OutPoint, []byte{})
msgtx.AddTxIn(txin)
for _, pubkeys := range msB.PubKeyList {
// M pubkey pubkey pubkey N OP_CHECKMULTISIG
scriptBuilder := btcscript.NewScriptBuilder().AddInt64(msB.M)
for _, pk := range pubkeys {
scriptBuilder = scriptBuilder.AddData(pk)
}
scriptBuilder = scriptBuilder.AddInt64(msB.N).AddOp(btcscript.OP_CHECKMULTISIG)
PkScript := scriptBuilder.Script()
txout := btcwire.NewTxOut(msB.eachOutVal(), PkScript)
msgtx.AddTxOut(txout)
}
// Sign this puppy
privkey := utxo.Wif.PrivKey
subscript := utxo.TxOut.PkScript
sigflag := btcscript.SigHashAll
scriptSig, err := btcscript.SignatureScript(msgtx, 0, subscript,
sigflag, privkey, true)
if err != nil {
return nil, err
}
msgtx.TxIn[0].SignatureScript = scriptSig
return msgtx, nil
}
// standardCoinbaseScript returns a standard script suitable for use as the
// signature script of the coinbase transaction of a new block. In particular,
// it starts with the block height that is required by version 2 blocks and adds
// the extra nonce as well as additional coinbase flags.
func standardCoinbaseScript(nextBlockHeight int64, extraNonce uint64) []byte {
return btcscript.NewScriptBuilder().AddInt64(nextBlockHeight).
AddUint64(extraNonce).AddData([]byte(coinbaseFlags)).Script()
}
// TestScriptBuilderAddData tests that pushing data to a script via the
// ScriptBuilder API works as expected.
func TestScriptBuilderAddData(t *testing.T) {
tests := []struct {
name string
data []byte
expected []byte
}{
// Start off with the small ints to ensure canonical encoding.
{name: "push small int 0", data: []byte{0}, expected: []byte{btcscript.OP_0}},
{name: "push small int 1", data: []byte{1}, expected: []byte{btcscript.OP_1}},
{name: "push small int 2", data: []byte{2}, expected: []byte{btcscript.OP_2}},
{name: "push small int 3", data: []byte{3}, expected: []byte{btcscript.OP_3}},
{name: "push small int 4", data: []byte{4}, expected: []byte{btcscript.OP_4}},
{name: "push small int 5", data: []byte{5}, expected: []byte{btcscript.OP_5}},
{name: "push small int 6", data: []byte{6}, expected: []byte{btcscript.OP_6}},
{name: "push small int 7", data: []byte{7}, expected: []byte{btcscript.OP_7}},
{name: "push small int 8", data: []byte{8}, expected: []byte{btcscript.OP_8}},
{name: "push small int 9", data: []byte{9}, expected: []byte{btcscript.OP_9}},
{name: "push small int 10", data: []byte{10}, expected: []byte{btcscript.OP_10}},
{name: "push small int 11", data: []byte{11}, expected: []byte{btcscript.OP_11}},
{name: "push small int 12", data: []byte{12}, expected: []byte{btcscript.OP_12}},
{name: "push small int 13", data: []byte{13}, expected: []byte{btcscript.OP_13}},
{name: "push small int 14", data: []byte{14}, expected: []byte{btcscript.OP_14}},
{name: "push small int 15", data: []byte{15}, expected: []byte{btcscript.OP_15}},
{name: "push small int 16", data: []byte{16}, expected: []byte{btcscript.OP_16}},
// 1-byte data push opcodes.
{
name: "push data len 17",
data: bytes.Repeat([]byte{0x49}, 17),
expected: append([]byte{btcscript.OP_DATA_17}, bytes.Repeat([]byte{0x49}, 17)...),
},
{
name: "push data len 75",
data: bytes.Repeat([]byte{0x49}, 75),
expected: append([]byte{btcscript.OP_DATA_75}, bytes.Repeat([]byte{0x49}, 75)...),
},
// 2-byte data push via OP_PUSHDATA_1.
{
name: "push data len 76",
data: bytes.Repeat([]byte{0x49}, 76),
expected: append([]byte{btcscript.OP_PUSHDATA1, 76}, bytes.Repeat([]byte{0x49}, 76)...),
},
{
name: "push data len 255",
data: bytes.Repeat([]byte{0x49}, 255),
expected: append([]byte{btcscript.OP_PUSHDATA1, 255}, bytes.Repeat([]byte{0x49}, 255)...),
},
// 3-byte data push via OP_PUSHDATA_2.
{
name: "push data len 256",
data: bytes.Repeat([]byte{0x49}, 256),
expected: append([]byte{btcscript.OP_PUSHDATA2, 0, 1}, bytes.Repeat([]byte{0x49}, 256)...),
},
{
name: "push data len 32767",
data: bytes.Repeat([]byte{0x49}, 32767),
expected: append([]byte{btcscript.OP_PUSHDATA2, 255, 127}, bytes.Repeat([]byte{0x49}, 32767)...),
},
// 5-byte data push via OP_PUSHDATA_4.
{
name: "push data len 65536",
data: bytes.Repeat([]byte{0x49}, 65536),
expected: append([]byte{btcscript.OP_PUSHDATA4, 0, 0, 1, 0}, bytes.Repeat([]byte{0x49}, 65536)...),
},
}
builder := btcscript.NewScriptBuilder()
t.Logf("Running %d tests", len(tests))
for i, test := range tests {
builder.Reset().AddData(test.data)
result := builder.Script()
if !bytes.Equal(result, test.expected) {
t.Errorf("ScriptBuilder.AddData #%d (%s) wrong result\n"+
"got: %x\nwant: %x", i, test.name, result,
test.expected)
continue
}
}
}