diff --git a/src/transaction_builder.js b/src/transaction_builder.js
index 778f593..cdaecc3 100644
--- a/src/transaction_builder.js
+++ b/src/transaction_builder.js
@@ -13,9 +13,20 @@ var Transaction = require('./transaction')
// inspects a scriptSig w/ optional redeemScript and
// derives any input information required
-function expandInput (scriptSig, redeemScript) {
- var scriptSigChunks = bscript.decompile(scriptSig)
- var prevOutType = bscript.classifyInput(scriptSigChunks, true)
+function expandInput (scriptSig, redeemScript, witnessStack) {
+ var witnessType
+ if (witnessStack) {
+ witnessType = bscript.classifyWitness(witnessStack)
+ }
+
+ var prevOutType, scriptSigChunks
+ if (scriptSig.length === 0 && witnessStack) {
+ prevOutType = witnessType
+ } else {
+ scriptSigChunks = bscript.decompile(scriptSig)
+ prevOutType = bscript.classifyInput(scriptSigChunks, true)
+ }
+
var pubKeys, signatures, prevOutScript
switch (prevOutType) {
@@ -31,8 +42,14 @@ function expandInput (scriptSig, redeemScript) {
result.redeemScriptType = result.prevOutType
result.prevOutScript = bscript.scriptHash.output.encode(bcrypto.hash160(redeemScript))
result.prevOutType = scriptTypes.P2SH
+ result.witness = false
return result
+ case scriptTypes.P2WPKH:
+ pubKeys = witnessStack.slice(1)
+ signatures = witnessStack.slice(0, 1)
+ break
+
case scriptTypes.P2PKH:
// if (redeemScript) throw new Error('Nonstandard... P2SH(P2PKH)')
pubKeys = scriptSigChunks.slice(1)
@@ -59,13 +76,19 @@ function expandInput (scriptSig, redeemScript) {
return chunk === ops.OP_0 ? undefined : chunk
})
break
+
+ case scriptTypes.NONSTANDARD:
+ return { prevOutType: prevOutType, prevOutScript: EMPTY_SCRIPT }
+
+ default: return {}
}
return {
pubKeys: pubKeys,
signatures: signatures,
prevOutScript: prevOutScript,
- prevOutType: prevOutType
+ prevOutType: prevOutType,
+ witness: Boolean(witnessStack)
}
}
@@ -123,6 +146,15 @@ function expandOutput (script, scriptType, ourPubKey) {
if (pkh1.equals(pkh2)) pubKeys = [ourPubKey]
break
+ // does our hash160(pubKey) match the output scripts?
+ case scriptTypes.P2WPKH:
+ if (!ourPubKey) break
+
+ var wpkh1 = scriptChunks[1]
+ var wpkh2 = bcrypto.hash160(ourPubKey)
+ if (wpkh1.equals(wpkh2)) pubKeys = [ourPubKey]
+ break
+
case scriptTypes.P2PK:
pubKeys = scriptChunks.slice(0, 1)
break
@@ -163,11 +195,15 @@ function prepareInput (input, kpPubKey, redeemScript) {
input.redeemScriptType = expanded.scriptType
input.prevOutScript = input.prevOutScript || bscript.scriptHash.output.encode(redeemScriptHash)
input.prevOutType = scriptTypes.P2SH
+ input.witness = false
// maybe we have some prevOut knowledge
} else if (input.prevOutType) {
- // pay-to-scriptHash is not possible without a redeemScript
- if (input.prevOutType === scriptTypes.P2SH) throw new Error('PrevOutScript is P2SH, missing redeemScript')
+ // embedded scripts are not possible without a redeemScript
+ if (input.prevOutType === scriptTypes.P2SH ||
+ input.prevOutType === scriptTypes.P2WSH) {
+ throw new Error('PrevOutScript is ' + input.prevOutType + ', requires redeemScript')
+ }
// try to derive missing information using our kpPubKey
expanded = expandOutput(input.prevOutScript, input.prevOutType, kpPubKey)
@@ -175,6 +211,7 @@ function prepareInput (input, kpPubKey, redeemScript) {
input.pubKeys = expanded.pubKeys
input.signatures = expanded.signatures
+ input.witness = (input.prevOutScript === scriptTypes.P2WPKH)
// no prior knowledge, assume pubKeyHash
} else {
@@ -182,24 +219,31 @@ function prepareInput (input, kpPubKey, redeemScript) {
input.prevOutType = scriptTypes.P2PKH
input.pubKeys = [kpPubKey]
input.signatures = [undefined]
+ input.witness = false
}
}
+var EMPTY_SCRIPT = new Buffer(0)
+
function buildInput (input, allowIncomplete) {
var signatures = input.signatures
var scriptType = input.redeemScriptType || input.prevOutType
- var scriptSig
+ var stack
switch (scriptType) {
+ case scriptTypes.P2WPKH:
+ if (signatures.length < 1 || !signatures[0]) throw new Error('Not enough signatures provided')
+ stack = bscript.witnessPubKeyHash.input.encodeStack(signatures[0], input.pubKeys[0])
+ break
+
case scriptTypes.P2PKH:
+ if (signatures.length < 1 || !signatures[0]) throw new Error('Not enough signatures provided')
+ stack = bscript.pubKeyHash.input.encodeStack(signatures[0], input.pubKeys[0])
+ break
+
case scriptTypes.P2PK:
if (signatures.length < 1 || !signatures[0]) throw new Error('Not enough signatures provided')
- if (scriptType === scriptTypes.P2PKH) {
- scriptSig = bscript.pubKeyHash.input.encode(signatures[0], input.pubKeys[0])
- } else {
- scriptSig = bscript.pubKey.input.encode(signatures[0])
- }
-
+ stack = bscript.pubKey.input.encodeStack(signatures[0])
break
// ref https://github.com/bitcoin/bitcoin/blob/d612837814020ae832499d18e6ee5eb919a87907/src/script/sign.cpp#L232
@@ -213,18 +257,40 @@ function buildInput (input, allowIncomplete) {
signatures = signatures.filter(function (x) { return x !== ops.OP_0 })
}
- scriptSig = bscript.multisig.input.encode(signatures, allowIncomplete ? undefined : input.redeemScript)
+ stack = bscript.multisig.input.encodeStack(signatures, allowIncomplete ? undefined : input.redeemScript)
break
default: return
}
- // wrap as scriptHash if necessary
- if (input.prevOutType === scriptTypes.P2SH) {
- scriptSig = bscript.scriptHash.input.encode(scriptSig, input.redeemScript)
+ var script, witness
+
+ // encode witness for P2WPKH if necessary
+ if (input.prevOutType === scriptTypes.P2WPKH ||
+ input.redeemScriptType === scriptTypes.P2WPKH) {
+ witness = stack
+ script = EMPTY_SCRIPT
}
- return scriptSig
+ // no witness? plain old script!
+ if (witness === undefined) {
+ script = bscript.compilePushOnly(stack)
+ }
+
+ // wrap as scriptHash if necessary
+ if (input.prevOutType === scriptTypes.P2SH) {
+ script = bscript.scriptHash.input.encode(script, input.redeemScript)
+ }
+
+ // falsy is easier
+ if (script === EMPTY_SCRIPT) {
+ script = undefined
+ }
+
+ return {
+ script: script,
+ witness: witness
+ }
}
function TransactionBuilder (network, maximumFeeRate) {
@@ -276,7 +342,8 @@ TransactionBuilder.fromTransaction = function (transaction, network) {
transaction.ins.forEach(function (txIn) {
txb.__addInputUnsafe(txIn.hash, txIn.index, {
sequence: txIn.sequence,
- script: txIn.script
+ script: txIn.script,
+ witness: txIn.witness
})
})
@@ -328,7 +395,7 @@ TransactionBuilder.prototype.__addInputUnsafe = function (txHash, vout, options)
// derive what we can from the scriptSig
if (options.script !== undefined) {
- input = expandInput(options.script)
+ input = expandInput(options.script, null, options.witness)
}
// if an input value was given, retain it
@@ -395,16 +462,14 @@ TransactionBuilder.prototype.__build = function (allowIncomplete) {
var scriptType = input.redeemScriptType || input.prevOutType
if (!scriptType && !allowIncomplete) throw new Error('Transaction is not complete')
- // build a scriptSig
- var scriptSig = buildInput(input, allowIncomplete)
+ var result = buildInput(input, allowIncomplete)
- // skip if no scriptSig exists
- if (!scriptSig) {
- if (!allowIncomplete) throw new Error(scriptType + ' not supported')
- return
- }
+ // skip if no result
+ if (!result && allowIncomplete) return
+ if (result && result.script) return tx.setInputScript(i, result.script)
+ if (result && result.witness) return tx.setWitness(i, result.witness)
- tx.setInputScript(i, scriptSig)
+ throw new Error(scriptType + ' not supported')
})
if (!allowIncomplete) {
@@ -422,10 +487,11 @@ function canSign (input) {
input.pubKeys !== undefined &&
input.signatures !== undefined &&
input.signatures.length === input.pubKeys.length &&
- input.pubKeys.length > 0
+ input.pubKeys.length > 0 &&
+ input.witness !== undefined
}
-TransactionBuilder.prototype.sign = function (vin, keyPair, redeemScript, hashType) {
+TransactionBuilder.prototype.sign = function (vin, keyPair, redeemScript, hashType, witnessValue) {
if (keyPair.network !== this.network) throw new Error('Inconsistent network')
if (!this.inputs[vin]) throw new Error('No input at index: ' + vin)
hashType = hashType || Transaction.SIGHASH_ALL
@@ -441,14 +507,20 @@ TransactionBuilder.prototype.sign = function (vin, keyPair, redeemScript, hashTy
var kpPubKey = keyPair.getPublicKeyBuffer()
if (!canSign(input)) {
- prepareInput(input, kpPubKey, redeemScript)
+ prepareInput(input, kpPubKey, redeemScript, witnessValue)
if (!canSign(input)) throw Error(input.prevOutType + ' not supported')
}
// ready to sign
var hashScript = input.redeemScript || input.prevOutScript
- var signatureHash = this.tx.hashForSignature(vin, hashScript, hashType)
+
+ var signatureHash
+ if (input.witness) {
+ signatureHash = this.tx.hashForWitnessV0(vin, hashScript, witnessValue, hashType)
+ } else {
+ signatureHash = this.tx.hashForSignature(vin, hashScript, hashType)
+ }
// enforce in order signing of public keys
var signed = input.pubKeys.some(function (pubKey, i) {
diff --git a/test/fixtures/transaction_builder.json b/test/fixtures/transaction_builder.json
index 811e998..855703d 100644
--- a/test/fixtures/transaction_builder.json
+++ b/test/fixtures/transaction_builder.json
@@ -377,6 +377,29 @@
"value": 10000
}
]
+ },
+ {
+ "description": "Transaction w/ P2WPKH -> P2WPKH",
+ "txHex": "01000000000101ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff0000000000ffffffff011027000000000000160014aa4d7985c57e011a8b3dd8e0e5a73aaef41629c5024730440220092de398bfbd808f6a2315c184cebf2f872692853482781eaeb72057706ac31202200a666c0eba2da011d04499b071143124559cad32a063785d713f2e0d4a15945101210279be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f8179800000000",
+ "inputs": [
+ {
+ "txId": "ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff",
+ "vout": 0,
+ "prevTxScript": "OP_0 751e76e8199196d454941c45d1b3a323f1433bd6",
+ "signs": [
+ {
+ "keyPair": "KwDiBf89QgGbjEhKnhXJuH7LrciVrZi3qYjgd9M7rFU73sVHnoWn",
+ "value": 10000
+ }
+ ]
+ }
+ ],
+ "outputs": [
+ {
+ "script": "OP_0 aa4d7985c57e011a8b3dd8e0e5a73aaef41629c5",
+ "value": 10000
+ }
+ ]
}
],
"fromTransaction": [
@@ -852,7 +875,7 @@
]
},
{
- "exception": "PrevOutScript is P2SH, missing redeemScript",
+ "exception": "PrevOutScript is scripthash, requires redeemScript",
"inputs": [
{
"txId": "ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff",
diff --git a/test/transaction_builder.js b/test/transaction_builder.js
index a33c075..fbe3315 100644
--- a/test/transaction_builder.js
+++ b/test/transaction_builder.js
@@ -283,10 +283,10 @@ describe('TransactionBuilder', function () {
}
if (!sign.throws) {
- txb.sign(index, keyPair, redeemScript, sign.hashType)
+ txb.sign(index, keyPair, redeemScript, sign.hashType, sign.value)
} else {
assert.throws(function () {
- txb.sign(index, keyPair, redeemScript, sign.hashType)
+ txb.sign(index, keyPair, redeemScript, sign.hashType, sign.value)
}, new RegExp(f.exception))
}
})