bitcoinjs-lib/src/transaction.js

468 lines
13 KiB
JavaScript

var bcrypto = require('./crypto')
var bscript = require('./script')
var bufferutils = require('./bufferutils')
var bufferReverse = require('buffer-reverse')
var opcodes = require('./opcodes.json')
var typeforce = require('typeforce')
var types = require('./types')
function varSliceSize (someScript) {
var length = someScript.length
return bufferutils.varIntSize(length) + length
}
function vectorSize (someVector) {
var length = someVector.length
return bufferutils.varIntSize(length) + someVector.reduce(function (sum, witness) {
return sum + varSliceSize(witness)
}, 0)
}
function Transaction () {
this.version = 1
this.locktime = 0
this.ins = []
this.outs = []
}
Transaction.DEFAULT_SEQUENCE = 0xffffffff
Transaction.SIGHASH_ALL = 0x01
Transaction.SIGHASH_NONE = 0x02
Transaction.SIGHASH_SINGLE = 0x03
Transaction.SIGHASH_ANYONECANPAY = 0x80
Transaction.ADVANCED_TRANSACTION_MARKER = 0x00
Transaction.ADVANCED_TRANSACTION_FLAG = 0x01
var EMPTY_SCRIPT = new Buffer(0)
var EMPTY_WITNESS = []
var ZERO = new Buffer('0000000000000000000000000000000000000000000000000000000000000000', 'hex')
var ONE = new Buffer('0000000000000000000000000000000000000000000000000000000000000001', 'hex')
var VALUE_UINT64_MAX = new Buffer('ffffffffffffffff', 'hex')
var BLANK_OUTPUT = {
script: EMPTY_SCRIPT,
valueBuffer: VALUE_UINT64_MAX
}
Transaction.fromBuffer = function (buffer, __noStrict) {
var offset = 0
function readSlice (n) {
offset += n
return buffer.slice(offset - n, offset)
}
function readUInt32 () {
var i = buffer.readUInt32LE(offset)
offset += 4
return i
}
function readInt32 () {
var i = buffer.readInt32LE(offset)
offset += 4
return i
}
function readUInt64 () {
var i = bufferutils.readUInt64LE(buffer, offset)
offset += 8
return i
}
function readVarInt () {
var vi = bufferutils.readVarInt(buffer, offset)
offset += vi.size
return vi.number
}
function readVarSlice () {
return readSlice(readVarInt())
}
function readVector () {
var count = readVarInt()
var vector = []
for (var i = 0; i < count; i++) vector.push(readVarSlice())
return vector
}
var tx = new Transaction()
tx.version = readInt32()
var marker = buffer.readUInt8(offset)
var flag = buffer.readUInt8(offset + 1)
var hasWitnesses = false
if (marker === Transaction.ADVANCED_TRANSACTION_MARKER &&
flag === Transaction.ADVANCED_TRANSACTION_FLAG) {
offset += 2
hasWitnesses = true
}
var vinLen = readVarInt()
for (var i = 0; i < vinLen; ++i) {
tx.ins.push({
hash: readSlice(32),
index: readUInt32(),
script: readVarSlice(),
sequence: readUInt32(),
witness: EMPTY_WITNESS
})
}
var voutLen = readVarInt()
for (i = 0; i < voutLen; ++i) {
tx.outs.push({
value: readUInt64(),
script: readVarSlice()
})
}
if (hasWitnesses) {
for (i = 0; i < vinLen; ++i) {
tx.ins[i].witness = readVector()
}
// was this pointless?
if (!tx._hasWitnesses()) throw new Error('Transaction has superfluous witness data')
}
tx.locktime = readUInt32()
if (__noStrict) return tx
if (offset !== buffer.length) throw new Error('Transaction has unexpected data')
return tx
}
Transaction.fromHex = function (hex) {
return Transaction.fromBuffer(new Buffer(hex, 'hex'))
}
Transaction.isCoinbaseHash = function (buffer) {
typeforce(types.Hash256bit, buffer)
for (var i = 0; i < 32; ++i) {
if (buffer[i] !== 0) return false
}
return true
}
Transaction.prototype.isCoinbase = function () {
return this.ins.length === 1 && Transaction.isCoinbaseHash(this.ins[0].hash)
}
Transaction.prototype.addInput = function (hash, index, sequence, scriptSig) {
typeforce(types.tuple(
types.Hash256bit,
types.UInt32,
types.maybe(types.UInt32),
types.maybe(types.Buffer)
), arguments)
if (types.Null(sequence)) {
sequence = Transaction.DEFAULT_SEQUENCE
}
// Add the input and return the input's index
return (this.ins.push({
hash: hash,
index: index,
script: scriptSig || EMPTY_SCRIPT,
sequence: sequence,
witness: EMPTY_WITNESS
}) - 1)
}
Transaction.prototype.addOutput = function (scriptPubKey, value) {
typeforce(types.tuple(types.Buffer, types.Satoshi), arguments)
// Add the output and return the output's index
return (this.outs.push({
script: scriptPubKey,
value: value
}) - 1)
}
Transaction.prototype._hasWitnesses = function () {
return this.ins.some(function (x) {
return x.witness.length !== 0
})
}
Transaction.prototype.byteLength = function () {
var hasWitnesses = this._hasWitnesses()
return (
(hasWitnesses ? 10 : 8) +
bufferutils.varIntSize(this.ins.length) +
bufferutils.varIntSize(this.outs.length) +
this.ins.reduce(function (sum, input) { return sum + 40 + varSliceSize(input.script) }, 0) +
this.outs.reduce(function (sum, output) { return sum + 8 + varSliceSize(output.script) }, 0) +
(hasWitnesses ? this.ins.reduce(function (sum, input) { return sum + vectorSize(input.witness) }, 0) : 0)
)
}
Transaction.prototype.clone = function () {
var newTx = new Transaction()
newTx.version = this.version
newTx.locktime = this.locktime
newTx.ins = this.ins.map(function (txIn) {
return {
hash: txIn.hash,
index: txIn.index,
script: txIn.script,
sequence: txIn.sequence,
witness: txIn.witness
}
})
newTx.outs = this.outs.map(function (txOut) {
return {
script: txOut.script,
value: txOut.value
}
})
return newTx
}
/**
* Hash transaction for signing a specific input.
*
* Bitcoin uses a different hash for each signed transaction input.
* This method copies the transaction, makes the necessary changes based on the
* hashType, and then hashes the result.
* This hash can then be used to sign the provided transaction input.
*/
Transaction.prototype.hashForSignature = function (inIndex, prevOutScript, hashType) {
typeforce(types.tuple(types.UInt32, types.Buffer, /* types.UInt8 */ types.Number), arguments)
// https://github.com/bitcoin/bitcoin/blob/master/src/test/sighash_tests.cpp#L29
if (inIndex >= this.ins.length) return ONE
// ignore OP_CODESEPARATOR
var ourScript = bscript.compile(bscript.decompile(prevOutScript).filter(function (x) {
return x !== opcodes.OP_CODESEPARATOR
}))
var txTmp = this.clone()
// SIGHASH_NONE: ignore all outputs? (wildcard payee)
if ((hashType & 0x1f) === Transaction.SIGHASH_NONE) {
txTmp.outs = []
// ignore sequence numbers (except at inIndex)
txTmp.ins.forEach(function (input, i) {
if (i === inIndex) return
input.sequence = 0
})
// SIGHASH_SINGLE: ignore all outputs, except at the same index?
} else if ((hashType & 0x1f) === Transaction.SIGHASH_SINGLE) {
// https://github.com/bitcoin/bitcoin/blob/master/src/test/sighash_tests.cpp#L60
if (inIndex >= this.outs.length) return ONE
// truncate outputs after
txTmp.outs.length = inIndex + 1
// "blank" outputs before
for (var i = 0; i < inIndex; i++) {
txTmp.outs[i] = BLANK_OUTPUT
}
// ignore sequence numbers (except at inIndex)
txTmp.ins.forEach(function (input, i) {
if (i === inIndex) return
input.sequence = 0
})
}
// SIGHASH_ANYONECANPAY: ignore inputs entirely?
if (hashType & Transaction.SIGHASH_ANYONECANPAY) {
txTmp.ins = [txTmp.ins[inIndex]]
txTmp.ins[0].script = ourScript
// SIGHASH_ALL: only ignore input scripts
} else {
// "blank" others input scripts
txTmp.ins.forEach(function (input) { input.script = EMPTY_SCRIPT })
txTmp.ins[inIndex].script = ourScript
}
// serialize and hash
var buffer = new Buffer(txTmp.byteLength() + 4)
buffer.writeInt32LE(hashType, buffer.length - 4)
txTmp.toBuffer(buffer, 0)
return bcrypto.hash256(buffer)
}
Transaction.prototype.hashForWitnessV0 = function (inIndex, prevOutScript, value, hashType) {
typeforce(types.tuple(types.UInt32, types.Buffer, types.Satoshi, types.UInt32), arguments)
var tbuffer, toffset
function writeSlice (slice) { toffset += slice.copy(tbuffer, toffset) }
function writeUInt32 (i) { toffset = tbuffer.writeUInt32LE(i, toffset) }
function writeUInt64 (i) { toffset = bufferutils.writeUInt64LE(tbuffer, i, toffset) }
function writeVarInt (i) { toffset += bufferutils.writeVarInt(tbuffer, i, toffset) }
function writeVarSlice (slice) { writeVarInt(slice.length); writeSlice(slice) }
var hashOutputs = ZERO
var hashPrevouts = ZERO
var hashSequence = ZERO
if (!(hashType & Transaction.SIGHASH_ANYONECANPAY)) {
tbuffer = new Buffer(36 * this.ins.length)
toffset = 0
this.ins.forEach(function (txIn) {
writeSlice(txIn.hash)
writeUInt32(txIn.index)
})
hashPrevouts = bcrypto.hash256(tbuffer)
}
if (!(hashType & Transaction.SIGHASH_ANYONECANPAY) &&
(hashType & 0x1f) !== Transaction.SIGHASH_SINGLE &&
(hashType & 0x1f) !== Transaction.SIGHASH_NONE) {
tbuffer = new Buffer(4 * this.ins.length)
toffset = 0
this.ins.forEach(function (txIn) {
writeUInt32(txIn.sequence)
})
hashSequence = bcrypto.hash256(tbuffer)
}
if ((hashType & 0x1f) !== Transaction.SIGHASH_SINGLE &&
(hashType & 0x1f) !== Transaction.SIGHASH_NONE) {
var txOutsSize = this.outs.reduce(function (sum, output) {
return sum + 8 + varSliceSize(output.script)
}, 0)
tbuffer = new Buffer(txOutsSize)
toffset = 0
this.outs.forEach(function (out) {
writeUInt64(out.value)
writeVarSlice(out.script)
})
hashOutputs = bcrypto.hash256(tbuffer)
} else if ((hashType & 0x1f) === Transaction.SIGHASH_SINGLE && inIndex < this.outs.length) {
var output = this.outs[inIndex]
tbuffer = new Buffer(8 + varSliceSize(output.script))
toffset = 0
writeUInt64(output.value)
writeVarSlice(output.script)
hashOutputs = bcrypto.hash256(tbuffer)
}
tbuffer = new Buffer(156 + varSliceSize(prevOutScript))
toffset = 0
var input = this.ins[inIndex]
writeUInt32(this.version)
writeSlice(hashPrevouts)
writeSlice(hashSequence)
writeSlice(input.hash)
writeUInt32(input.index)
writeVarSlice(prevOutScript)
writeUInt64(value)
writeUInt32(input.sequence)
writeSlice(hashOutputs)
writeUInt32(this.locktime)
writeUInt32(hashType)
return bcrypto.hash256(tbuffer)
}
Transaction.prototype.getHash = function () {
return bcrypto.hash256(this.toBuffer())
}
Transaction.prototype.getId = function () {
// transaction hash's are displayed in reverse order
return bufferReverse(this.getHash()).toString('hex')
}
Transaction.prototype.toBuffer = function (buffer, initialOffset) {
if (!buffer) buffer = new Buffer(this.byteLength())
var offset = initialOffset || 0
function writeSlice (slice) { offset += slice.copy(buffer, offset) }
function writeUInt8 (i) { offset = buffer.writeUInt8(i, offset) }
function writeUInt32 (i) { offset = buffer.writeUInt32LE(i, offset) }
function writeInt32 (i) { offset = buffer.writeInt32LE(i, offset) }
function writeUInt64 (i) { offset = bufferutils.writeUInt64LE(buffer, i, offset) }
function writeVarInt (i) { offset += bufferutils.writeVarInt(buffer, i, offset) }
function writeVarSlice (slice) { writeVarInt(slice.length); writeSlice(slice) }
function writeVector (vector) { writeVarInt(vector.length); vector.forEach(writeVarSlice) }
writeInt32(this.version)
var hasWitnesses = this._hasWitnesses()
if (hasWitnesses) {
writeUInt8(Transaction.ADVANCED_TRANSACTION_MARKER)
writeUInt8(Transaction.ADVANCED_TRANSACTION_FLAG)
}
writeVarInt(this.ins.length)
this.ins.forEach(function (txIn) {
writeSlice(txIn.hash)
writeUInt32(txIn.index)
writeVarSlice(txIn.script)
writeUInt32(txIn.sequence)
})
writeVarInt(this.outs.length)
this.outs.forEach(function (txOut) {
if (!txOut.valueBuffer) {
writeUInt64(txOut.value)
} else {
writeSlice(txOut.valueBuffer)
}
writeVarSlice(txOut.script)
})
if (hasWitnesses) {
this.ins.forEach(function (input) {
writeVector(input.witness)
})
}
writeUInt32(this.locktime)
// avoid slicing unless necessary
if (initialOffset !== undefined) return buffer.slice(initialOffset, offset)
return buffer
}
Transaction.prototype.toHex = function () {
return this.toBuffer().toString('hex')
}
Transaction.prototype.setInputScript = function (index, scriptSig) {
typeforce(types.tuple(types.Number, types.Buffer), arguments)
this.ins[index].script = scriptSig
}
Transaction.prototype.setWitness = function (index, witness) {
typeforce(types.tuple(types.Number, types.Buffer), arguments)
this.ins[index].witness = witness
}
module.exports = Transaction