fcoin/lib/bcoin/script.js
Christopher Jeffrey 7b1af73c46 address parsing.
2016-03-31 01:54:07 -07:00

2874 lines
69 KiB
JavaScript

/**
* script.js - script interpreter for bcoin
* Copyright (c) 2014-2015, Fedor Indutny (MIT License)
* https://github.com/indutny/bcoin
*/
var bcoin = require('../bcoin');
var bn = require('bn.js');
var constants = bcoin.protocol.constants;
var utils = require('./utils');
var assert = utils.assert;
var BufferWriter = require('./writer');
var opcodes = constants.opcodes;
var STACK_TRUE = new Buffer([1]);
var STACK_FALSE = new Buffer([]);
var STACK_NEGATE = new Buffer([0xff]);
function Witness(items) {
if (items instanceof Witness)
return items;
if (!(this instanceof Witness))
return new Witness(items);
if (!items)
items = [];
if (items.items)
items = items.items;
this.items = items || [];
this.redeem = null;
}
Witness.prototype.inspect = function inspect() {
return Script.format(this.items);
};
Witness.prototype.clone = function clone() {
return new Witness(this.items.slice());
};
Witness.prototype.toStack = function toStack() {
return new Stack(this.items.slice());
};
Witness.prototype.getInputType = function getInputType(prev) {
return Script.getInputType(this.items, prev, true);
};
Witness.prototype.getInputAddress = function getInputAddress(prev) {
return Script.getInputAddress(this.items, prev, true);
};
Witness.prototype.getInputHash = function getInputHash(prev) {
return Script.getInputHash(this.items, prev, true);
};
Witness.prototype.isPubkeyInput = function isPubkeyInput(key) {
return Script.isPubkeyInput(this.items, key);
};
Witness.prototype.isPubkeyhashInput = function isPubkeyhashInput(hash) {
return Script.isPubkeyhashInput(this.items, hash);
};
Witness.prototype.isMultisigInput = function isMultisigInput(keys) {
return Script.isMultisigInput(this.items, keys, true);
};
Witness.prototype.isScripthashInput = function isScripthashInput(redeem) {
return Script.isScripthashInput(this.items, redeem, true);
};
Witness.prototype.isNonstandardInput = function isNonstandardInput(prev) {
return Script.isNonstandardInput(this.items, prev, true);
};
Witness.prototype.getRedeem = function getRedeem() {
if (!this.redeem)
this.redeem = Script.getRedeem(this.items);
return this.redeem;
};
Witness.fromString = function fromString(items) {
var i, op, symbol;
items = items.trim().split(/\s+/);
for (i = 0; i < items.length; i++) {
op = items[i].toLowerCase();
if (op.indexOf('op_') === 0)
op = op.slice(3);
if (op === '-1' || op === '1negate') {
op = STACK_NEGATE;
} else if (op === '0' || op === 'false') {
op = STACK_FALSE;
} else if (op === 'true') {
op = STACK_TRUE;
} else if (+op >= 1 && +op <= 16) {
op = new Buffer([+op]);
} else {
symbol = 'OP_' + op.toUpperCase();
if (opcodes[symbol] == null) {
if (op[0] === '[')
op = op.slice(1, -1);
if (op.indexOf('0x') === 0)
op = op.substring(2);
assert(utils.isHex(op), 'Non-stack item in witness string.');
op = new Buffer(op, 'hex');
} else {
assert(false, 'Non-stack item in witness string.');
}
}
items[i] = op;
}
return new Witness(items);
};
Witness.fromSymbolic = function fromSymbolic(items) {
var code = new Array(items.length);
var i, op, symbol;
for (i = 0; i < items.length; i++) {
op = items[i];
if (Buffer.isBuffer(op)) {
code[i] = op;
continue;
}
op = (op + '').toLowerCase();
if (op.indexOf('op_') === 0)
op = op.slice(3);
if (+op === -1)
op = STACK_NEGATE;
else if (+op === 0 || op === 'false')
op = STACK_FALSE;
else if (+op === 1 || op === 'true')
op = STACK_TRUE;
else if (+op >= 1 && +op <= 16)
op = new Buffer([+op]);
else
assert(false, 'Non-stack item in witness string.');
code[i] = op;
}
return new Witness(code);
};
Witness.isWitness = function isWitness(obj) {
return obj
&& Array.isArray(obj.items)
&& typeof obj.toStack === 'function';
};
function Stack(items) {
this.items = items || [];
this.alt = [];
}
Stack.prototype.inspect = function inspect() {
return Script.format(this.items);
};
Stack.prototype.__defineGetter__('length', function() {
return this.items.length;
});
Stack.prototype.__defineSetter__('length', function(value) {
return this.items.length = value;
});
Stack.prototype.getRedeem = function getRedeem(pop) {
var redeem = Script.getRedeem(this.items);
if (!redeem)
return;
if (pop !== false)
this.pop();
return redeem;
};
Stack.prototype.clone = function clone() {
var stack = new Stack(this.items.slice());
stack.alt = this.alt.slice();
return stack;
};
Stack.prototype.getSize = function getSize() {
return this.items.length + this.alt.length;
};
Stack.prototype.push = function push(item) {
return this.items.push(item);
};
Stack.prototype.unshift = function unshift(item) {
return this.items.unshift(item);
};
Stack.prototype.slice = function slice(start, end) {
return this.items.slice(start, end);
};
Stack.prototype.splice = function splice(i, remove, insert) {
return this.items.splice(i, remove, insert);
};
Stack.prototype.pop = function pop() {
return this.items.pop();
};
Stack.prototype.shift = function shift() {
return this.items.shift();
};
Stack.prototype.get = function get(i) {
return this.items[i];
};
Stack.prototype.top = function top(i) {
return this.items[this.items.length + i];
};
Stack.prototype.set = function set(i, value) {
return this.items[i] = value;
};
Stack.prototype._swap = function _swap(i1, i2) {
var v1, v2;
i1 = this.items.length + i1;
i2 = this.items.length + i2;
v1 = this.items[i1];
v2 = this.items[i2];
this.items[i1] = v2;
this.items[i2] = v1;
};
Stack.prototype.toalt = function toalt() {
if (this.length === 0)
throw new ScriptError('Stack too small.', opcodes.OP_TOALTSTACK);
this.alt.push(this.pop());
};
Stack.prototype.fromalt = function fromalt() {
if (this.alt.length === 0)
throw new ScriptError('Stack too small.', opcodes.OP_FROMALTSTACK);
this.push(this.alt.pop());
};
Stack.prototype.ifdup = function ifdup() {
if (this.length === 0)
throw new ScriptError('Stack too small.', opcodes.OP_IFDUP);
if (Script.bool(this.top(-1)))
this.push(Script.array(this.top(-1)));
};
Stack.prototype.depth = function depth() {
this.push(Script.array(this.length));
};
Stack.prototype.drop = function drop() {
if (this.length === 0)
throw new ScriptError('Stack too small.', opcodes.OP_DROP);
this.pop();
};
Stack.prototype.dup = function dup() {
if (this.length === 0)
throw new ScriptError('Stack too small.', opcodes.OP_DUP);
this.push(this.top(-1));
};
Stack.prototype.nip = function nip() {
if (this.length < 2)
throw new ScriptError('Stack too small.', opcodes.OP_NIP);
this.splice(this.length - 2, 1);
};
Stack.prototype.over = function over() {
if (this.length < 2)
throw new ScriptError('Stack too small.', opcodes.OP_OVER);
this.push(this.top(-2));
};
Stack.prototype.pick = function pick(flags) {
return this._pickroll(opcodes.OP_PICK, flags);
};
Stack.prototype.roll = function roll(flags) {
return this._pickroll(opcodes.OP_ROLL, flags);
};
Stack.prototype._pickroll = function pickroll(op, flags) {
var val, n;
if (this.length < 2)
throw new ScriptError('Stack too small.', op);
val = this.pop();
n = Script.num(val, flags).toNumber();
if (n <= 0 || n > this.length)
throw new ScriptError('Bad value.', op);
val = this.get(-n - 1);
if (op === opcodes.OP_ROLL)
this.splice(this.length - n - 1, 1);
this.push(val);
};
Stack.prototype.rot = function rot() {
if (this.length < 3)
throw new ScriptError('Stack too small.', opcodes.OP_ROT);
this._swap(-3, -2);
this._swap(-2, -1);
};
Stack.prototype.swap = function swap() {
if (this.length < 2)
throw new ScriptError('Stack too small.', opcodes.OP_SWAP);
this._swap(-2, -1);
};
Stack.prototype.tuck = function tuck() {
if (this.length < 2)
throw new ScriptError('Stack too small.', opcodes.OP_TUCK);
this.splice(this.length - 2, 0, this.top(-1));
};
Stack.prototype.drop2 = function drop2() {
if (this.length < 2)
throw new ScriptError('Stack too small.', opcodes.OP_2DROP);
this.pop();
this.pop();
};
Stack.prototype.dup2 = function dup2() {
var v1, v2;
if (this.length < 2)
throw new ScriptError('Stack too small.', opcodes.OP_2DUP);
v1 = this.top(-2);
v2 = this.top(-1);
this.push(v1);
this.push(v2);
};
Stack.prototype.dup3 = function dup3() {
var v1, v2, v3;
if (this.length < 3)
throw new ScriptError('Stack too small.', opcodes.OP_3DUP);
v1 = this.top(-3);
v2 = this.top(-2);
v3 = this.top(-1);
this.push(v1);
this.push(v2);
this.push(v3);
};
Stack.prototype.over2 = function over2() {
var v1, v2;
if (this.length < 4)
throw new ScriptError('Stack too small.', opcodes.OP_2OVER);
v1 = this.top(-4);
v2 = this.top(-3);
this.push(v1);
this.push(v2);
};
Stack.prototype.rot2 = function rot2() {
var v1, v2;
if (this.length < 6)
throw new ScriptError('Stack too small.', opcodes.OP_2ROT);
v1 = this.top(-6);
v2 = this.top(-5);
this.splice(this.length - 6, 2);
this.push(v1);
this.push(v2);
};
Stack.prototype.swap2 = function swap2() {
this._swap(-4, -2);
this._swap(-3, -1);
};
Stack.prototype.size = function size() {
if (this.length < 1)
throw new ScriptError('Stack too small.', opcodes.OP_SIZE);
this.push(Script.array(this.top(-1).length));
};
Stack.isStack = function isStack(obj) {
return obj && Array.isArray(obj.alt) && typeof obj.swap2 === 'function';
};
/**
* Script
*/
function Script(code) {
if (code instanceof Script)
return code;
if (!(this instanceof Script))
return new Script(code);
if (Buffer.isBuffer(code)) {
this.raw = code;
this.code = Script.decode(code);
} else {
if (!code)
code = [];
if (code.code) {
this.raw = code.raw || null;
this.code = code.code;
if (!this.code)
this.code = Script.decode(this.raw);
} else {
assert(Array.isArray(code));
this.raw = null;
this.code = code;
}
}
this.redeem = null;
}
Script.prototype.clone = function clone() {
return new Script(this.code.slice());
};
Script.prototype.inspect = function inspect() {
return Script.format(this.code);
};
Script.prototype.encode = function encode() {
if (!this.raw)
this.raw = Script.encode(this.code);
return this.raw;
};
Script.prototype.getSubscript = function getSubscript(lastSep) {
var res = [];
var i;
if (lastSep == null)
lastSep = -1;
assert(lastSep <= 0 || this.code[lastSep] === opcodes.OP_CODESEPARATOR);
for (i = lastSep + 1; i < this.code.length; i++) {
if (this.code[i] !== opcodes.OP_CODESEPARATOR)
res.push(this.code[i]);
}
// Optimization: avoid re-rendering
// of the script in 99.9% of cases.
if (res.length === this.code.length) {
res = this.clone();
res.raw = this.raw;
return res;
}
return new Script(res);
};
Script.prototype._next = function _next(to, code, ip) {
var depth = 0;
var op;
while (code[ip]) {
op = code[ip];
if (op === opcodes.OP_IF || op === opcodes.OP_NOTIF)
depth++;
else if (op === opcodes.OP_ELSE)
depth--;
else if (op === opcodes.OP_ENDIF)
depth--;
if (depth < 0)
break;
if (depth === 0 && op === to)
return ip;
if (op === opcodes.OP_ELSE)
depth++;
ip++;
}
return -1;
};
Script.prototype.execute = function execute(stack, flags, tx, index, version) {
try {
return this.interpret(stack, flags, tx, index, version);
} catch (e) {
if (e.type === 'ScriptError') {
utils.debug('Script error: %s.', e.message);
} else {
utils.debug('Script interpreter threw:');
utils.debug(e.stack + '');
}
return false;
}
};
Script.prototype.interpret = function interpret(stack, flags, tx, index, version) {
var code = this.code.slice();
var ip = 0;
var lastSep = -1;
var op, val;
var if_, else_, endif;
var n, n1, n2, n3;
var res;
var key, sig, type, subscript, hash;
var keys, i, j, m;
var succ;
var locktime;
if (flags == null)
flags = constants.flags.STANDARD_VERIFY_FLAGS;
if (code.length > constants.script.maxOps)
throw new ScriptError('Script too large.');
for (ip = 0; ip < code.length; ip++) {
op = code[ip];
if (Buffer.isBuffer(op)) {
if (op.length > constants.script.maxPush)
throw new ScriptError('Push data too large.', op, ip);
if (!Script.checkPush(op, flags))
throw new ScriptError('Push verification failed.', op, ip);
stack.push(op);
continue;
}
if (op === opcodes.OP_0) {
stack.push(STACK_FALSE);
continue;
}
if (op >= opcodes.OP_1 && op <= opcodes.OP_16) {
stack.push(new Buffer([op - 0x50]));
continue;
}
switch (op) {
case opcodes.OP_NOP:
case opcodes.OP_NOP1:
case opcodes.OP_NOP4:
case opcodes.OP_NOP5:
case opcodes.OP_NOP6:
case opcodes.OP_NOP7:
case opcodes.OP_NOP8:
case opcodes.OP_NOP9:
case opcodes.OP_NOP10: {
if (flags & constants.flags.VERIFY_DISCOURAGE_UPGRADABLE_NOPS)
throw new ScriptError('Upgradable NOP used.', op, ip);
break;
}
case opcodes.OP_1NEGATE: {
stack.push(STACK_NEGATE);
break;
}
case opcodes.OP_IF:
case opcodes.OP_NOTIF: {
if (stack.length < 1)
throw new ScriptError('Stack too small.', op, ip);
val = Script.bool(stack.pop());
if (op === opcodes.OP_NOTIF)
val = !val;
if_ = ip;
else_ = this._next(opcodes.OP_ELSE, code, ip);
endif = this._next(opcodes.OP_ENDIF, code, ip);
// Splice out the statement blocks we don't need
if (val) {
if (endif === -1)
throw new ScriptError('Missing endif.', op, ip);
if (else_ === -1) {
code.splice(endif, 1);
code.splice(if_, 1);
} else {
code.splice(else_, (endif - else_) + 1);
code.splice(if_, 1);
}
} else {
if (endif === -1)
throw new ScriptError('Missing endif.', op, ip);
if (else_ === -1) {
code.splice(if_, (endif - if_) + 1);
} else {
code.splice(endif, 1);
code.splice(if_, (else_ - if_) + 1);
}
}
// Subtract one since we removed the if/notif opcode
ip--;
break;
}
case opcodes.OP_ELSE: {
throw new ScriptError('Unexpected else.', op, ip);
}
case opcodes.OP_ENDIF: {
throw new ScriptError('Unexpected endif.', op, ip);
}
case opcodes.OP_VERIFY: {
if (stack.length === 0)
throw new ScriptError('Stack too small.', op, ip);
if (!Script.bool(stack.pop()))
throw new ScriptError('Verification failed.', op, ip);
break;
}
case opcodes.OP_RETURN: {
throw new ScriptError('Script returned.', op, ip);
}
case opcodes.OP_TOALTSTACK: {
stack.toalt();
break;
}
case opcodes.OP_FROMALTSTACK: {
stack.fromalt();
break;
}
case opcodes.OP_IFDUP: {
stack.ifdup();
break;
}
case opcodes.OP_DEPTH: {
stack.depth();
break;
}
case opcodes.OP_DROP: {
stack.drop();
break;
}
case opcodes.OP_DUP: {
stack.dup();
break;
}
case opcodes.OP_NIP: {
stack.nip();
break;
}
case opcodes.OP_OVER: {
stack.over();
break;
}
case opcodes.OP_PICK: {
stack.pick(flags);
break;
}
case opcodes.OP_ROLL: {
stack.roll(flags);
break;
}
case opcodes.OP_ROT: {
stack.rot();
break;
}
case opcodes.OP_SWAP: {
stack.swap();
break;
}
case opcodes.OP_TUCK: {
stack.tuck();
break;
}
case opcodes.OP_2DROP: {
stack.drop2();
break;
}
case opcodes.OP_2DUP: {
stack.dup2();
break;
}
case opcodes.OP_3DUP: {
stack.dup3();
break;
}
case opcodes.OP_2OVER: {
stack.over2();
break;
}
case opcodes.OP_2ROT: {
stack.rot2();
break;
}
case opcodes.OP_2SWAP: {
stack.swap2();
break;
}
case opcodes.OP_SIZE: {
stack.size();
break;
}
case opcodes.OP_1ADD:
case opcodes.OP_1SUB:
case opcodes.OP_NEGATE:
case opcodes.OP_ABS:
case opcodes.OP_NOT:
case opcodes.OP_0NOTEQUAL: {
if (stack.length < 1)
throw new ScriptError('Stack too small.', op, ip);
n = Script.num(stack.pop(), flags);
switch (op) {
case opcodes.OP_1ADD:
n.iadd(1);
break;
case opcodes.OP_1SUB:
n.isub(1);
break;
case opcodes.OP_NEGATE:
n = n.neg();
break;
case opcodes.OP_ABS:
if (n.cmpn(0) < 0)
n.ineg();
break;
case opcodes.OP_NOT:
n = n.cmpn(0) === 0;
break;
case opcodes.OP_0NOTEQUAL:
n = n.cmpn(0) !== 0;
break;
default:
return false;
}
if (typeof n === 'boolean')
n = new bn(n ? 1 : 0, 'le');
stack.push(Script.array(n));
break;
}
case opcodes.OP_ADD:
case opcodes.OP_SUB:
case opcodes.OP_BOOLAND:
case opcodes.OP_BOOLOR:
case opcodes.OP_NUMEQUAL:
case opcodes.OP_NUMEQUALVERIFY:
case opcodes.OP_NUMNOTEQUAL:
case opcodes.OP_LESSTHAN:
case opcodes.OP_GREATERTHAN:
case opcodes.OP_LESSTHANOREQUAL:
case opcodes.OP_GREATERTHANOREQUAL:
case opcodes.OP_MIN:
case opcodes.OP_MAX: {
switch (op) {
case opcodes.OP_ADD:
case opcodes.OP_SUB:
case opcodes.OP_BOOLAND:
case opcodes.OP_BOOLOR:
case opcodes.OP_NUMEQUAL:
case opcodes.OP_NUMEQUALVERIFY:
case opcodes.OP_NUMNOTEQUAL:
case opcodes.OP_LESSTHAN:
case opcodes.OP_GREATERTHAN:
case opcodes.OP_LESSTHANOREQUAL:
case opcodes.OP_GREATERTHANOREQUAL:
case opcodes.OP_MIN:
case opcodes.OP_MAX:
if (stack.length < 2)
throw new ScriptError('Stack too small.', op, ip);
n2 = Script.num(stack.pop(), flags);
n1 = Script.num(stack.pop(), flags);
n = new bn(0, 'le');
switch (op) {
case opcodes.OP_ADD:
n = n1.add(n2);
break;
case opcodes.OP_SUB:
n = n1.sub(n2);
break;
case opcodes.OP_BOOLAND:
n = n1.cmpn(0) !== 0 && n2.cmpn(0) !== 0;
break;
case opcodes.OP_BOOLOR:
n = n1.cmpn(0) !== 0 || n2.cmpn(0) !== 0;
break;
case opcodes.OP_NUMEQUAL:
n = n1.cmp(n2) === 0;
break;
case opcodes.OP_NUMEQUALVERIFY:
n = n1.cmp(n2) === 0;
break;
case opcodes.OP_NUMNOTEQUAL:
n = n1.cmp(n2) !== 0;
break;
case opcodes.OP_LESSTHAN:
n = n1.cmp(n2) < 0;
break;
case opcodes.OP_GREATERTHAN:
n = n1.cmp(n2) > 0;
break;
case opcodes.OP_LESSTHANOREQUAL:
n = n1.cmp(n2) <= 0;
break;
case opcodes.OP_GREATERTHANOREQUAL:
n = n1.cmp(n2) >= 0;
break;
case opcodes.OP_MIN:
n = n1.cmp(n2) < 0 ? n1 : n2;
break;
case opcodes.OP_MAX:
n = n1.cmp(n2) > 0 ? n1 : n2;
break;
default:
return false;
}
if (typeof n === 'boolean')
n = new bn(n ? 1 : 0, 'le');
res = Script.bool(n);
if (op === opcodes.OP_NUMEQUALVERIFY) {
if (!res)
return false;
} else {
stack.push(Script.array(n));
}
break;
case opcodes.OP_WITHIN:
if (stack.length < 3)
throw new ScriptError('Stack too small.', op, ip);
n3 = Script.num(stack.pop(), flags);
n2 = Script.num(stack.pop(), flags);
n1 = Script.num(stack.pop(), flags);
val = n2.cmp(n1) <= 0 && n1.cmp(n3) < 0;
stack.push(val.cmpn(0) !== 0 ? STACK_TRUE : STACK_FALSE);
break;
}
break;
}
case opcodes.OP_CODESEPARATOR: {
lastSep = ip;
break;
}
case opcodes.OP_RIPEMD160: {
if (stack.length === 0)
throw new ScriptError('Stack too small.', op, ip);
stack.push(utils.ripemd160(stack.pop()));
break;
}
case opcodes.OP_SHA1: {
if (stack.length === 0)
throw new ScriptError('Stack too small.', op, ip);
stack.push(utils.sha1(stack.pop()));
break;
}
case opcodes.OP_SHA256: {
if (stack.length === 0)
throw new ScriptError('Stack too small.', op, ip);
stack.push(utils.sha256(stack.pop()));
break;
}
case opcodes.OP_HASH256: {
if (stack.length === 0)
throw new ScriptError('Stack too small.', op, ip);
stack.push(utils.dsha256(stack.pop()));
break;
}
case opcodes.OP_HASH160: {
if (stack.length === 0)
throw new ScriptError('Stack too small.', op, ip);
stack.push(utils.ripesha(stack.pop()));
break;
}
case opcodes.OP_EQUALVERIFY:
case opcodes.OP_EQUAL: {
if (stack.length < 2)
throw new ScriptError('Stack too small.', op, ip);
res = utils.isEqual(stack.pop(), stack.pop());
if (op === opcodes.OP_EQUALVERIFY) {
if (!res)
throw new ScriptError('Equal verification failed.', op, ip);
} else {
stack.push(res ? STACK_TRUE : STACK_FALSE);
}
break;
}
case opcodes.OP_CHECKSIGVERIFY:
case opcodes.OP_CHECKSIG: {
if (!tx)
throw new ScriptError('No TX passed in.', op, ip);
if (stack.length < 2)
throw new ScriptError('Stack too small.', op, ip);
key = stack.pop();
sig = stack.pop();
if (!Script.isValidKey(key, flags))
throw new ScriptError('Key is not valid.', op, ip);
if (!Script.isValidSignature(sig, flags))
throw new ScriptError('Signature is not valid.', op, ip);
type = sig[sig.length - 1];
subscript = this.getSubscript(lastSep);
subscript.removeData(sig);
hash = tx.signatureHash(index, subscript, type, version);
res = Script.checksig(hash, sig, key, flags);
if (op === opcodes.OP_CHECKSIGVERIFY) {
if (!res)
throw new ScriptError('Signature verification failed.', op, ip);
} else {
stack.push(res ? STACK_TRUE : STACK_FALSE);
}
break;
}
case opcodes.OP_CHECKMULTISIGVERIFY:
case opcodes.OP_CHECKMULTISIG: {
if (!tx)
throw new ScriptError('No TX passed in.', op, ip);
if (stack.length < 4)
throw new ScriptError('Stack too small.', op, ip);
n = Script.num(stack.pop(), flags).toNumber();
if (!(n >= 1 && n <= 15))
throw new ScriptError('`n` is out of bounds.', op, ip);
if (stack.length < n + 1)
throw new ScriptError('`n` exceeds stack size.', op, ip);
keys = [];
for (i = 0; i < n; i++) {
key = stack.pop();
if (!Script.isValidKey(key, flags))
throw new ScriptError('Key is not valid.', op, ip);
keys.push(key);
}
m = Script.num(stack.pop(), flags).toNumber();
if (!(m >= 1 && m <= n))
throw new ScriptError('`m` is out of bounds.', op, ip);
if (stack.length < m)
throw new ScriptError('`m` exceeds stack size.', op, ip);
subscript = this.getSubscript(lastSep);
for (i = 0; i < m; i++) {
sig = stack.get(stack.length - 1 - i);
subscript.removeData(sig);
}
succ = 0;
for (i = 0, j = 0; i < m; i++) {
sig = stack.pop();
if (!Script.isValidSignature(sig, flags))
throw new ScriptError('Signature is not valid.', op, ip);
type = sig[sig.length - 1];
hash = tx.signatureHash(index, subscript, type, version);
res = false;
for (; !res && j < n; j++)
res = Script.checksig(hash, sig, keys[j], flags);
if (res)
succ++;
}
if (stack.length < 1)
throw new ScriptError('No dummy present.', op, ip);
val = stack.pop();
if (flags & constants.flags.VERIFY_NULLDUMMY) {
if (!Script.isDummy(val))
throw new ScriptError('Dummy did not verify.', op, ip);
}
res = succ >= m;
if (op === opcodes.OP_CHECKMULTISIGVERIFY) {
if (!res)
throw new ScriptError('Signature verification failed.', op, ip);
} else {
stack.push(res ? STACK_TRUE : STACK_FALSE);
}
break;
}
case opcodes.OP_CHECKLOCKTIMEVERIFY: {
// OP_CHECKLOCKTIMEVERIFY = OP_NOP2
if (!(flags & constants.flags.VERIFY_CHECKLOCKTIMEVERIFY)) {
if (flags & constants.flags.VERIFY_DISCOURAGE_UPGRADABLE_NOPS)
throw new ScriptError('Upgradable NOP used.', op, ip);
break;
}
if (!tx)
throw new ScriptError('No TX passed in.', op, ip);
if (stack.length === 0)
throw new ScriptError('Stack too small.', op, ip);
// NOTE: Bitcoind accepts 5 byte locktimes.
// 4 byte locktimes become useless in 2106.
locktime = Script.num(stack.top(-1), flags, 5).toNumber();
if (locktime < 0)
throw new ScriptError('Negative locktime.', op, ip);
if (!Script.checkLocktime(locktime, tx, index))
throw new ScriptError('Locktime verification failed.', op, ip);
break;
}
case opcodes.OP_CHECKSEQUENCEVERIFY: {
// OP_CHECKSEQUENCEVERIFY = OP_NOP3
if (!(flags & constants.flags.VERIFY_CHECKSEQUENCEVERIFY)) {
if (flags & constants.flags.VERIFY_DISCOURAGE_UPGRADABLE_NOPS)
throw new ScriptError('Upgradable NOP used.', op, ip);
break;
}
if (!tx)
throw new ScriptError('No TX passed in.', op, ip);
if (stack.length === 0)
throw new ScriptError('Stack too small.', op, ip);
// NOTE: Bitcoind accepts 5 byte locktimes.
// 4 byte locktimes become useless in 2106
// (will people still be using bcoin then?).
locktime = Script.num(stack.top(-1), flags, 4).toNumber();
if (locktime < 0)
throw new ScriptError('Negative sequence.', op, ip);
if ((locktime & constants.sequenceLocktimeDisableFlag) !== 0)
break;
if (!Script.checkSequence(locktime, tx, index))
throw new ScriptError('Sequence verification failed.', op, ip);
break;
}
default: {
throw new ScriptError('Unknown opcode.', op, ip);
}
}
}
if (stack.getSize() > constants.script.maxStack)
throw new ScriptError('Stack size too large.', op, ip);
return true;
};
Script.checkLocktime = function checkLocktime(locktime, tx, i) {
var threshold = constants.locktimeThreshold;
if (!(
(tx.locktime < threshold && locktime < threshold)
|| (tx.locktime >= threshold && locktime >= threshold)
)) {
return false;
}
if (locktime > tx.locktime)
return false;
if (tx.inputs[i].sequence === 0xffffffff)
return false;
return true;
};
Script.checkSequence = function checkSequence(sequence, tx, i) {
var txSequence = tx.inputs[i].sequence;
var locktimeMask, txSequenceMasked, sequenceMasked;
if ((tx.version >>> 0) < 2)
return false;
if (txSequence & constants.sequenceLocktimeDisableFlag)
return false;
locktimeMask = constants.sequenceLocktimeTypeFlag
| constants.sequenceLocktimeMask;
txSequenceMasked = txSequence & locktimeMask;
sequenceMasked = sequence & locktimeMask;
if (!(
(txSequenceMasked < constants.sequenceLocktimeTypeFlag
&& sequenceMasked < constants.sequenceLocktimeTypeFlag)
|| (txSequenceMasked >= constants.sequenceLocktimeTypeFlag
&& sequenceMasked >= constants.sequenceLocktimeTypeFlag)
)) {
return false;
}
if (sequenceMasked > txSequenceMasked)
return false;
return true;
};
Script.bool = function bool(value) {
var i;
// Should never happen:
// if (typeof value === 'boolean')
// return value;
// Should never happen:
// if (utils.isFinite(value))
// return value !== 0;
if (bn.isBN(value))
return value.cmpn(0) !== 0;
assert(Buffer.isBuffer(value));
for (i = 0; i < value.length; i++) {
if (value[i] !== 0) {
// Cannot be negative zero
if (i === value.length - 1 && value[i] === 0x80)
return false;
return true;
}
}
return false;
};
Script.num = function num(value, flags, size) {
assert(Buffer.isBuffer(value));
if (flags == null)
flags = constants.flags.STANDARD_VERIFY_FLAGS;
if (size == null)
size = 4;
if (value.length > size)
throw new ScriptError('Script number overflow.');
if ((flags & constants.flags.VERIFY_MINIMALDATA) && value.length > 0) {
// If the low bits on the last byte are unset,
// fail if the value's second to last byte does
// not have the high bit set. A number can't
// justify having the last byte's low bits unset
// unless they ran out of space for the sign bit
// in the second to last bit. We also fail on [0]
// to avoid negative zero (also avoids positive
// zero).
if (!(value[value.length - 1] & 0x7f)) {
if (value.length === 1 || !(value[value.length - 2] & 0x80))
throw new ScriptError('Non-minimally encoded Script number.');
}
}
// If we are signed, do (~num + 1) to get
// the positive counterpart and set bn's
// negative flag.
if (value[value.length - 1] & 0x80) {
if (utils.isNegZero(value, 'le')) {
value = new bn(0, 'le');
} else {
value = new bn(value, 'le');
value = value.notn(value.bitLength()).addn(1).neg();
}
} else {
value = new bn(value, 'le');
}
return value;
};
Script.array = function(value) {
if (Buffer.isBuffer(value))
return value;
if (utils.isFinite(value))
value = new bn(value, 'le');
assert(bn.isBN(value));
// Convert the number to the
// negative byte representation.
if (value.isNeg()) {
if (value.cmpn(0) === 0)
value = new bn(0);
else
value = value.neg().notn(value.bitLength()).subn(1);
}
if (value.cmpn(0) === 0)
return STACK_FALSE;
return value.toBuffer('le');
};
Script.prototype.removeData = function removeData(data) {
for (var i = this.code.length - 1; i >= 0; i--) {
if (utils.isEqual(this.code[i], data))
this.code.splice(i, 1);
}
};
Script.checkPush = function checkPush(value, flags) {
var pushdata = value.pushdata;
if (flags == null)
flags = constants.flags.STANDARD_VERIFY_FLAGS;
if (!(flags & constants.flags.VERIFY_MINIMALDATA))
return true;
if (!pushdata)
return true;
if (value.length === 1 && value[0] === 0)
return false;
if (value.length === 1 && value[0] >= 1 && value[0] <= 16)
return false;
if (value.length === 1 && value[0] === 0xff)
return false;
if (value.length <= 75)
return pushdata.opcode == null && pushdata.size === value.length;
if (value.length <= 255)
return pushdata.opcode === opcodes.OP_PUSHDATA1;
if (value.length <= 65535)
return pushdata.opcode === opcodes.OP_PUSHDATA2;
return true;
};
Script.isCode = function isCode(buf) {
var i, op, code;
if (!buf)
return false;
if (!Buffer.isBuffer(buf))
return false;
code = Script.decode(buf);
for (i = 0; i < code.length; i++) {
op = code[i];
if (Buffer.isBuffer(op))
continue;
if (constants.opcodesByVal[op] == null)
return false;
}
return true;
};
Script.prototype.concat = function concat(scripts) {
scripts.unshift(this);
return Script.concat(scripts);
};
Script.createPubkey = function createPubkey(key) {
return new Script([key, opcodes.OP_CHECKSIG]);
};
Script.createPubkeyhash = function createPubkeyhash(hash) {
return new Script([
opcodes.OP_DUP,
opcodes.OP_HASH160,
hash,
opcodes.OP_EQUALVERIFY,
opcodes.OP_CHECKSIG
]);
};
Script.createMultisig = function createMultisig(keys, m, n) {
var code = [];
var i;
assert(keys.length === n, '`n` keys are required for multisig.');
assert(m >= 1 && m <= n);
assert(n >= 1 && n <= 15);
keys = utils.sortKeys(keys);
code.push(m + 0x50);
for (i = 0; i < keys.length; i++)
code.push(keys[i]);
code.push(n + 0x50);
code.push(opcodes.OP_CHECKMULTISIG);
return new Script(code);
};
Script.createScripthash = function createScripthash(hash) {
return new Script([
opcodes.OP_HASH160,
hash,
opcodes.OP_EQUAL
]);
};
Script.createNulldata = function createNulldata(flags) {
return new Script([
opcodes.OP_RETURN,
flags
]);
};
Script.createWitnessProgram = function createWitnessProgram(version, data) {
assert(typeof version === 'number' && version >= 0 && version <= 16);
assert(Buffer.isBuffer(data));
assert(data.length === 20 || data.length === 32);
return new Script([version === 0 ? 0 : version + 0x50, data]);
};
Script.prototype.getRedeem = function getRedeem() {
if (!this.redeem)
this.redeem = Script.getRedeem(this.code);
return this.redeem;
};
Script.getRedeem = function getRedeem(code) {
var redeem = code[code.length - 1];
if (!Buffer.isBuffer(redeem))
return;
return new Script(redeem);
};
Script.prototype.getType = function getType() {
if (this.isCommitment())
return 'commitment';
if (this.isWitnessProgram()) {
if (this.isWitnessPubkeyhash())
return 'witnesspubkeyhash';
if (this.isWitnessScripthash())
return 'witnessscripthash';
return 'unknown';
}
return (this.isPubkey() && 'pubkey')
|| (this.isPubkeyhash() && 'pubkeyhash')
|| (this.isMultisig() && 'multisig')
|| (this.isScripthash() && 'scripthash')
|| (this.isNulldata() && 'nulldata')
|| 'unknown';
};
Script.prototype.isNonstandard = function isNonstandard() {
return this.getType() === 'unknown';
};
Script.prototype.isStandard = function isStandard() {
var type = this.getType();
var m, n;
if (type === 'multisig') {
m = Script.getSmall(this.code[0]);
n = Script.getSmall(this.code[this.code.length - 2]);
if (n < 1 || n > 3)
return false;
if (m < 1 || m > n)
return false;
} else if (type === 'nulldata') {
if (this.getSize() > constants.script.maxOpReturnBytes)
return false;
}
return type !== 'unknown';
};
Script.prototype.isStandardProgram = function isStandardProgram(witness, flags) {
var program, witnessScript, i;
assert((flags & constants.flags.VERIFY_WITNESS) !== 0);
assert(this.isWitnessProgram());
program = this.getWitnessProgram();
if (!program.type)
return false;
if (program.version > 0) {
if (flags & constants.flags.VERIFY_DISCOURAGE_UPGRADABLE_WITNESS_PROGRAM)
return false;
return true;
}
if (program.type === 'witnesspubkeyhash') {
if (witness.items.length !== 2)
return false;
} else if (program.type === 'witnessscripthash') {
if (witness.items.length === 0)
return false;
} else {
assert(false);
}
for (i = 0; i < witness.items.length; i++) {
if (witness.items[i].length > constants.script.maxSize)
return false;
}
return true;
};
Script.prototype.getSize = function getSize() {
return this.encode().length;
};
Script.prototype.getInputAddress = function getInputAddress(prev) {
return Script.getInputAddress(this.code, prev, false);
};
Script.getInputAddress = function getInputAddress(code, prev, isWitness) {
if (prev)
return prev.getAddress();
if (Script.isPubkeyInput(code))
return;
if (Script.isPubkeyhashInput(code)) {
return bcoin.address.compileData(code[1],
isWitness ? 'witnesspubkeyhash' : 'pubkeyhash');
}
if (Script.isMultisigInput(code, null, isWitness))
return;
if (Script.isScripthashInput(code, null, isWitness)) {
return bcoin.address.compileData(code[code.length - 1],
isWitness ? 'witnessscripthash' : 'scripthash');
}
};
Script.prototype.getAddress = function getAddress() {
var program;
if (this.isWitnessProgram()) {
program = this.getWitnessProgram();
if (!program.type || program.type === 'unknown')
return;
return bcoin.address.compileHash(program.data, program.type);
}
// Convert p2pk to p2pkh addresses
if (this.isPubkey())
return bcoin.address.compileData(this.code[0], 'pubkeyhash');
if (this.isPubkeyhash())
return bcoin.address.compileHash(this.code[2], 'pubkeyhash');
// Convert bare multisig to scripthash address
if (this.isMultisig())
return bcoin.address.compileData(this.encode(), 'scripthash');
if (this.isScripthash())
return bcoin.address.compileHash(this.code[1], 'scripthash');
};
Script.prototype.getInputHash = function getInputHash(prev) {
return Script.getInputHash(this.code, prev, false);
};
Script.getInputHash = function getInputHash(prev, isWitness) {
if (prev)
return prev.getHash();
if (Script.isPubkeyInput(code))
return;
if (Script.isPubkeyhashInput(code))
return utils.ripesha(code[1]);
if (Script.isMultisigInput(code, null, isWitness))
return;
if (Script.isScripthashInput(code, null, isWitness)) {
return isWitness
? utils.sha256(code[code.length - 1])
: utils.ripesha(code[code.length - 1]);
}
};
Script.prototype.getHash = function getHash() {
var program;
if (this.isWitnessProgram()) {
program = this.getWitnessProgram();
if (!program.type || program.type === 'unknown')
return;
return program.data;
}
if (this.isPubkey())
return utils.ripesha(this.code[0]);
if (this.isPubkeyhash())
return this.code[2];
if (this.isMultisig())
return utils.ripesha(this.encode());
if (this.isScripthash())
return this.code[1];
};
Script.prototype.isPubkey = function isPubkey(key) {
var res;
if (this.code.length !== 2)
return false;
res = Script.isKey(this.code[0]) && this.code[1] === opcodes.OP_CHECKSIG;
if (!res)
return false;
if (key) {
if (!utils.isEqual(this.code[0], key))
return false;
}
return true;
};
Script.prototype.isPubkeyhash = function isPubkeyhash(hash) {
var res;
if (this.code.length !== 5)
return false;
res = this.code[0] === opcodes.OP_DUP
&& this.code[1] === opcodes.OP_HASH160
&& Script.isHash(this.code[2])
&& this.code[3] === opcodes.OP_EQUALVERIFY
&& this.code[4] === opcodes.OP_CHECKSIG;
if (!res)
return false;
if (hash) {
if (!utils.isEqual(this.code[2], hash))
return false;
}
return true;
};
Script.prototype.isMultisig = function isMultisig(keys) {
var m, n, i, j;
var total = 0;
if (this.code.length < 4)
return false;
if (this.code[this.code.length - 1] !== opcodes.OP_CHECKMULTISIG)
return false;
n = Script.getSmall(this.code[this.code.length - 2]);
if (n == null)
return false;
m = Script.getSmall(this.code[0]);
if (m == null)
return false;
if (!(m >= 1 && m <= n))
return false;
if (n + 3 !== this.code.length)
return false;
for (i = 1; i < n + 1; i++) {
if (!Script.isKey(this.code[i]))
return false;
}
if (keys) {
for (i = 1; i < n + 1; i++) {
for (j = 0; j < keys.length; j++) {
if (utils.isEqual(this.code[i], keys[j])) {
total++;
break;
}
}
}
if (total !== n)
return false;
}
return true;
};
Script.prototype.isScripthash = function isScripthash(hash) {
var res;
if (this.code.length !== 3)
return false;
res = this.code[0] === opcodes.OP_HASH160
&& Script.isHash(this.code[1])
&& this.code[2] === opcodes.OP_EQUAL;
if (!res)
return false;
if (hash) {
if (!utils.isEqual(this.code[1], hash))
return false;
}
return true;
};
Script.prototype.isNulldata = function isNulldata() {
var res;
if (this.code.length !== 2)
return false;
res = this.code[0] === opcodes.OP_RETURN && Script.isData(this.code[1]);
if (!res)
return false;
return true;
};
Script.prototype.isCommitment = function isCommitment() {
return this.code.length >= 2
&& this.code[0] === opcodes.OP_RETURN
&& Buffer.isBuffer(this.code[1])
&& this.code[1].length === 36
&& utils.readU32BE(this.code[1], 0) === 0xaa21a9ed;
};
Script.prototype.createCommitment = function createCommitment(hash) {
return new Script([
opcodes.OP_RETURN,
Buffer.concat([new Buffer([0xaa, 0x21, 0xa9, 0xed]), hash])
]);
};
Script.prototype.getCommitmentHash = function getCommitmentHash() {
if (!this.isCommitment())
return;
return this.code[1].slice(4, 36);
};
Script.prototype.isWitnessProgram = function isWitnessProgram() {
if (this.code.length !== 2)
return false;
if (typeof this.code[0] !== 'number')
return false;
if (!Buffer.isBuffer(this.code[1]))
return false;
return (this.code[0] === opcodes.OP_0
|| (this.code[0] >= opcodes.OP_1 && this.code[0] <= opcodes.OP_16))
&& this.code[1].length >= 2 && this.code[1].length <= 32;
};
Script.prototype.getWitnessProgram = function getWitnessProgram() {
var version, data, type;
if (!this.isWitnessProgram())
return;
version = Script.getSmall(this.code[0]);
data = this.code[1];
if (version > 0) {
// No interpretation of script (anyone can spend)
type = 'unknown';
} else if (version === 0 && data.length === 20) {
type = 'witnesspubkeyhash';
} else if (version === 0 && data.length === 32) {
type = 'witnessscripthash';
} else {
// Fail on bad version=0
type = null;
}
return {
version: version,
type: type,
data: data
};
};
Script.prototype.isWitnessPubkeyhash = function isWitnessPubkeyhash() {
if (!this.isWitnessProgram())
return false;
return this.code[0] === opcodes.OP_0 && this.code[1].length === 20;
};
Script.prototype.isWitnessScripthash = function isWitnessScripthash() {
if (!this.isWitnessProgram())
return false;
return this.code[0] === opcodes.OP_0 && this.code[1].length === 32;
};
Script.prototype.getInputType = function getInputType(prev) {
return Script.getInputType(this.code, prev);
};
Script.getInputType = function getInputType(code, prev, isWitness) {
var type;
if (prev)
return prev.getType();
type = (Script.isPubkeyInput(code) && 'pubkey')
|| (Script.isPubkeyhashInput(code) && 'pubkeyhash')
|| (Script.isMultisigInput(code, null, isWitness) && 'multisig')
|| (Script.isScripthashInput(code, null, isWitness) && 'scripthash')
|| 'unknown';
if (isWitness) {
if (type === 'pubkeyhash')
return 'witnesspubkeyhash';
if (type === 'scripthash')
return 'witnessscripthash';
return 'unknown';
}
return type;
};
Script.prototype.isNonstandardInput = function isNonstandardInput(prev) {
return Script.isNonstandardInput(this.code, prev, false);
};
Script.isNonstandardInput = function isNonstandardInput(code, prev, isWitness) {
return Script.getInputType(code, prev, isWitness) === 'unknown';
};
Script.createOutputScript = function(options) {
var script, keys, m, n, hash, flags, address, redeem;
if (!options)
options = {};
if (options.keys) {
keys = options.keys.map(utils.ensureBuffer);
m = options.m;
n = options.n || keys.length;
assert(m >= 1 && m <= n, 'm must be between 1 and n');
assert(
n >= 1 && n <= (options.scriptHash ? 15 : 3),
'n must be between 1 and 15');
script = Script.createMultisig(keys, m, n);
} else if (options.address) {
address = bcoin.address.parse(options.address);
if (address.type === 'pubkeyhash')
script = Script.createPubkeyhash(address.hash);
else if (address.type === 'scripthash')
script = Script.createScripthash(address.hash);
else if (address.version !== -1)
script = Script.createWitnessProgram(address.version, address.hash);
else
assert(false);
} else if (options.key) {
script = Script.createPubkey(utils.ensureBuffer(options.key));
} else if (options.flags) {
flags = options.flags;
if (typeof flags === 'string')
flags = new Buffer(flags, 'ascii');
assert(Buffer.isBuffer(flags));
assert(flags.length <= constants.script.maxOpReturn);
script = Script.createNulldata(flags);
}
if (options.scriptHash) {
if (options.locktime != null) {
script = new Script([
Script.array(options.locktime),
opcodes.OP_CHECKLOCKTIMEVERIFY,
opcodes.OP_DROP
].concat(script.code));
}
redeem = script;
hash = utils.ripesha(script.encode());
script = Script.createScripthash(hash);
script.redeem = redeem;
}
return script;
};
Script.prototype.isPubkeyInput = function isPubkeyInput(key) {
return Script.isPubkeyInput(this.code, key);
};
Script.isPubkeyInput = function isPubkeyInput(code, key) {
if (code.length !== 1)
return false;
if (!Script.isSignature(code[0]))
return false;
assert(!key);
return true;
};
Script.prototype.isPubkeyhashInput = function isPubkeyhashInput(key) {
return Script.isPubkeyhashInput(this.code, key);
};
Script.isPubkeyhashInput = function isPubkeyhashInput(code, key) {
if (code.length !== 2)
return false;
if (!Script.isSignature(code[0]))
return false;
if (!Script.isKey(code[1]))
return false;
if (key) {
if (!utils.isEqual(code[1], key))
return false;
}
return true;
};
Script.prototype.isMultisigInput = function isMultisigInput(keys) {
return Script.isMultisigInput(this.code, keys);
};
Script.isMultisigInput = function isMultisigInput(code, keys, isWitness) {
var i;
// We need to rule out scripthash because
// it may look like multisig. This is
// strange because it's technically a
// recursive call.
if (Script.isScripthashInput(code, null, isWitness))
return false;
if (code.length < 3)
return false;
if (isWitness) {
if (!Script.isDummy(code[0]))
return false;
} else {
if (code[0] !== opcodes.OP_0)
return false;
}
for (i = 1; i < code.length; i++) {
if (!Script.isSignature(code[i]))
return false;
}
assert(!keys);
return true;
};
Script.prototype.isScripthashInput = function isScripthashInput(redeem) {
return Script.isScripthashInput(this.code, redeem);
};
Script.isScripthashInput = function isScripthashInput(code, redeem, isWitness) {
var raw;
// Grab the raw redeem script.
raw = code[code.length - 1];
// Need at least one data element with
// the redeem script. NOTE: NOT THE CASE FOR SEGWIT!
if (isWitness) {
if (code.length < 1)
return false;
} else {
if (code.length < 2)
return false;
}
// Last data element should be an array
// for the redeem script.
if (!Buffer.isBuffer(raw))
return false;
// Check data against last array in case
// a raw redeem script was passed in.
if (redeem)
return utils.isEqual(redeem.encode(), raw);
// Testing for scripthash inputs requires
// some evil magic to work. We do it by
// ruling things _out_. This test will not
// be correct 100% of the time. We rule
// out that the last data element is: a
// null dummy, a valid signature, a valid
// key, and we ensure that it is at least
// a script that does not use undefined
// opcodes.
if (Script.isDummy(raw))
return false;
if (Script.isSignatureEncoding(raw))
return false;
if (Script.isKeyEncoding(raw))
return false;
if (!Script.isCode(raw))
return false;
return true;
};
Script.prototype.getCoinbaseData = function getCoinbaseData() {
var coinbase, flags;
coinbase = {
script: this
};
if (Buffer.isBuffer(this.code[0]) && this.code[0].length <= 6)
coinbase.height = new bn(this.code[0], 'le').toNumber();
else
coinbase.height = -1;
if (Buffer.isBuffer(this.code[1]))
coinbase.extraNonce = new bn(this.code[1], 'le');
else
coinbase.extraNonce = new bn(0, 'le');
flags = this.code.slice(2).filter(function(chunk) {
return Buffer.isBuffer(chunk) && chunk.length !== 0;
});
coinbase.flags = flags;
flags = flags.map(function(flag) {
return flag.toString('utf8');
});
coinbase.text = flags.join('').replace(/[\u0000-\u0019\u007f-\u00ff]/g, '');
return coinbase;
};
// Detect script array types. Note: these functions
// are not mutually exclusive. Only use for
// verification, not detection.
Script.isHash = function isHash(hash) {
if (!Buffer.isBuffer(hash))
return false;
return hash.length === 20;
};
Script.isKey = function isKey(key) {
if (!Buffer.isBuffer(key))
return false;
return key.length >= 33 && key.length <= 65;
};
Script.isSignature = function isSignature(sig) {
if (!Buffer.isBuffer(sig))
return false;
return sig.length >= 9 && sig.length <= 73;
};
Script.isDummy = function isDummy(data) {
if (!Buffer.isBuffer(data))
return false;
return data.length === 0;
};
Script.isZero = function isZero(op) {
if (op === opcodes.OP_0)
return true;
return Script.isDummy(op);
};
Script.isData = function isData(data) {
if (!Buffer.isBuffer(data))
return false;
return data.length <= constants.script.maxOpReturn;
};
Script.isValidKey = function isValidKey(key, flags) {
if (flags == null)
flags = constants.flags.STANDARD_VERIFY_FLAGS;
if (!Buffer.isBuffer(key))
return false;
if (flags & constants.flags.VERIFY_STRICTENC) {
if (!Script.isKeyEncoding(key)) {
utils.debug('Script failed key encoding test.');
return false;
}
}
return true;
};
Script.isKeyEncoding = function isKeyEncoding(key) {
if (!Buffer.isBuffer(key))
return false;
if (key.length < 33)
return false;
if (key[0] === 0x04) {
if (key.length !== 65)
return false;
} else if (key[0] === 0x02 || key[0] === 0x03) {
if (key.length !== 33)
return false;
} else {
return false;
}
return true;
};
Script.isValidSignature = function isValidSignature(sig, flags) {
if (flags == null)
flags = constants.flags.STANDARD_VERIFY_FLAGS;
if (!Buffer.isBuffer(sig))
return false;
// Allow empty sigs
if (sig.length === 0)
return true;
if ((flags & constants.flags.VERIFY_DERSIG)
|| (flags & constants.flags.VERIFY_LOW_S)
|| (flags & constants.flags.VERIFY_STRICTENC)) {
if (!Script.isSignatureEncoding(sig)) {
utils.debug('Script does not have a proper signature encoding.');
return false;
}
}
if (flags & constants.flags.VERIFY_LOW_S) {
if (!Script.isLowDER(sig)) {
utils.debug('Script does not have a low DER.');
return false;
}
}
if (flags & constants.flags.VERIFY_STRICTENC) {
if (!Script.isHashType(sig)) {
utils.debug('Script does not have a valid hash type.');
return false;
}
}
return true;
};
// https://github.com/bitcoin/bips/blob/master/bip-0066.mediawiki
/**
* A canonical signature exists of: <30> <total len> <02> <len R> <R> <02> <len S> <S> <hashtype>
* Where R and S are not negative (their first byte has its highest bit not set), and not
* excessively padded (do not start with a 0 byte, unless an otherwise negative number follows,
* in which case a single 0 byte is necessary and even required).
*
* See https://bitcointalk.org/index.php?topic=8392.msg127623#msg127623
*
* This function is consensus-critical since BIP66.
*/
Script.isSignatureEncoding = function isSignatureEncoding(sig) {
var lenR, lenS;
if (!Buffer.isBuffer(sig))
return false;
// Format: 0x30 [total-length] 0x02 [R-length] [R] 0x02 [S-length] [S] [sighash]
// * total-length: 1-byte length descriptor of everything that follows,
// excluding the sighash byte.
// * R-length: 1-byte length descriptor of the R value that follows.
// * R: arbitrary-length big-endian encoded R value. It must use the shortest
// possible encoding for a positive integers (which means no null bytes at
// the start, except a single one when the next byte has its highest bit set).
// * S-length: 1-byte length descriptor of the S value that follows.
// * S: arbitrary-length big-endian encoded S value. The same rules apply.
// * sighash: 1-byte value indicating what data is hashed (not part of the DER
// signature)
// Minimum and maximum size constraints.
if (sig.length < 9)
return false;
if (sig.length > 73)
return false;
// A signature is of type 0x30 (compound).
if (sig[0] !== 0x30)
return false;
// Make sure the length covers the entire signature.
if (sig[1] !== sig.length - 3)
return false;
// Extract the length of the R element.
lenR = sig[3];
// Make sure the length of the S element is still inside the signature.
if (5 + lenR >= sig.length)
return false;
// Extract the length of the S element.
lenS = sig[5 + lenR];
// Verify that the length of the signature matches the sum of the length
// of the elements.
if (lenR + lenS + 7 !== sig.length)
return false;
// Check whether the R element is an integer.
if (sig[2] !== 0x02)
return false;
// Zero-length integers are not allowed for R.
if (lenR === 0)
return false;
// Negative numbers are not allowed for R.
if (sig[4] & 0x80)
return false;
// Null bytes at the start of R are not allowed, unless R would
// otherwise be interpreted as a negative number.
if (lenR > 1 && (sig[4] === 0x00) && !(sig[5] & 0x80))
return false;
// Check whether the S element is an integer.
if (sig[lenR + 4] !== 0x02)
return false;
// Zero-length integers are not allowed for S.
if (lenS === 0)
return false;
// Negative numbers are not allowed for S.
if (sig[lenR + 6] & 0x80)
return false;
// Null bytes at the start of S are not allowed, unless S would otherwise be
// interpreted as a negative number.
if (lenS > 1 && (sig[lenR + 6] === 0x00) && !(sig[lenR + 7] & 0x80))
return false;
return true;
};
Script.isHashType = function isHashType(sig) {
var type;
if (!Buffer.isBuffer(sig))
return false;
if (sig.length === 0)
return false;
type = sig[sig.length - 1] & ~constants.hashType.anyonecanpay;
if (!constants.hashTypeByVal[type])
return false;
return true;
};
Script.isLowDER = function isLowDER(sig) {
if (!sig.s) {
if (!Buffer.isBuffer(sig))
return false;
if (!Script.isSignatureEncoding(sig))
return false;
sig = sig.slice(0, -1);
}
return bcoin.ec.isLowS(sig);
};
Script.format = function format(code) {
var scripts = [];
if (Array.isArray(code)) {
scripts.push({ code: code });
} else if (code instanceof Stack) {
scripts.push({ code: code.items });
} else if (code instanceof Witness) {
scripts.push({ code: code.items });
} else if (code instanceof Script) {
scripts.push(code);
} else if (code instanceof bcoin.input) {
scripts.push(code.script);
if (code.witness.length > 0)
scripts.push({ code: code.witness.items });
if (code.coin) {
scripts.push(code.coin.script);
if (code.coin.script.isScripthash())
scripts.push(code.coin.script.getRedeem());
}
} else if (code instanceof bcoin.output) {
scripts.push(code.script);
}
return Script.concat(scripts).map(function(chunk) {
if (Buffer.isBuffer(chunk))
return '[' + utils.toHex(chunk) + ']';
assert(typeof chunk === 'number');
if (constants.opcodesByVal[chunk])
return constants.opcodesByVal[chunk];
chunk = chunk.toString(16);
if (chunk.length < 2)
chunk = '0' + chunk;
return 'UNKNOWN(' + chunk + ')';
}).join(' ');
};
Script.prototype.isPushOnly = function isPushOnly() {
var i, op;
for (i = 0; i < this.code.length; i++) {
op = this.code[i];
if (Buffer.isBuffer(op)
|| op === opcodes.OP_1NEGATE
|| op === opcodes.OP_0
|| (op >= opcodes.OP_1 && op <= opcodes.OP_16)) {
continue;
}
return false;
}
return true;
};
Script.prototype.getSigops = function getSigops(accurate) {
var total = 0;
var lastOp = -1;
var i, op;
for (i = 0; i < this.code.length; i++) {
op = this.code[i];
if (Buffer.isBuffer(op))
continue;
if (constants.opcodesByVal[op] == null)
return 0;
if (op === opcodes.OP_CHECKSIG || op === opcodes.OP_CHECKSIGVERIFY) {
total++;
} else if (op === opcodes.OP_CHECKMULTISIG || op === opcodes.OP_CHECKMULTISIGVERIFY) {
if (accurate && lastOp >= opcodes.OP_1 && lastOp <= opcodes.OP_16)
total += lastOp;
else
total += constants.script.maxPubkeysPerMultisig;
}
lastOp = op;
}
return total;
};
Script.prototype.getArgs = function getArgs() {
var keys, m;
if (this.isPubkey())
return 1;
if (this.isPubkeyhash())
return 2;
if (this.isMultisig()) {
keys = this.code.length - 3;
m = Script.getSmall(this.code[0]);
if (keys < 1 || m < 1)
return -1;
return m + 1;
}
if (this.isScripthash())
return 1;
if (this.isNulldata())
return -1;
if (this.isWitnessScripthash())
return 1;
if (this.isWitnessPubkeyhash())
return 2;
return -1;
};
Script.fromString = function fromString(code) {
var i, op, symbol;
code = code.trim().split(/\s+/);
for (i = 0; i < code.length; i++) {
op = code[i];
if (op === '-1')
op = '1negate';
symbol = (op + '').toUpperCase();
if (symbol.indexOf('OP_') !== 0)
symbol = 'OP_' + op;
if (opcodes[symbol] == null) {
if (op[0] === '[')
op = op.slice(1, -1);
if (op.indexOf('0x') === 0)
op = op.substring(2);
assert(utils.isHex(op), 'Unknown opcode.');
op = new Buffer(op, 'hex');
code[i] = op;
continue;
}
code[i] = opcodes[symbol];
}
return new Script(code);
};
Script.prototype.getSmall = function getSmall(i) {
if (i < 0)
i = this.code.length + i;
return Script.getSmall(this.code[i]);
};
Script.getSmall = function getSmall(op) {
if (typeof op !== 'number')
return null;
if (op === opcodes.OP_0)
return 0;
if (op >= opcodes.OP_1 && op <= opcodes.OP_16)
return op - 0x50;
return null;
};
Script.toSmall = function toSmall(op) {
assert(op >= 0 && op <= 16);
if (op === 0)
return opcodes.OP_0;
return op + 0x50;
};
Script.fromSymbolic = function fromSymbolic(items) {
var code = new Array(items.length);
var i, op;
for (i = 0; i < items.length; i++) {
op = items[i];
if (Buffer.isBuffer(op)) {
code[i] = op;
continue;
}
if (+op === -1)
op = '1negate';
op = (op + '').toUpperCase();
if (op.indexOf('OP_') !== 0)
op = 'OP_' + op;
assert(opcodes[op] != null, 'Unknown opcode.');
code[i] = opcodes[op];
}
return new Script(code);
};
Script.verify = function verify(input, witness, output, tx, i, flags) {
var copy, res, raw, redeem, hadWitness;
var stack = new Stack();
if (flags == null)
flags = constants.flags.STANDARD_VERIFY_FLAGS;
if (flags & constants.flags.VERIFY_SIGPUSHONLY) {
if (!input.isPushOnly())
return false;
}
// Execute the input script
input.execute(stack, flags, tx, i, 0);
// Copy the stack for P2SH
if (flags & constants.flags.VERIFY_P2SH)
copy = stack.clone();
// Execute the previous output script
res = output.execute(stack, flags, tx, i, 0);
// Verify the script did not fail as well as the stack values
if (!res || stack.length === 0 || !Script.bool(stack.pop()))
return false;
if ((flags & constants.flags.VERIFY_WITNESS) && output.isWitnessProgram()) {
hadWitness = true;
// Input script must be empty.
if (input.code.length !== 0)
return false;
// Verify the program in the output script
if (!Script.verifyProgram(witness, output, flags, tx, i))
return false;
// Force a cleanstack
stack.length = 0;
}
// If the script is P2SH, execute the real output script
if ((flags & constants.flags.VERIFY_P2SH) && output.isScripthash()) {
// P2SH can only have push ops in the scriptSig
if (!input.isPushOnly())
return false;
// Reset the stack
stack = copy;
// Stack should not be empty at this point
if (stack.length === 0)
return false;
// Grab the real redeem script
raw = stack.pop();
if (!Buffer.isBuffer(raw))
return false;
redeem = new Script(raw);
// Execute the redeem script
res = redeem.execute(stack, flags, tx, i, 0);
// Verify the script did not fail as well as the stack values
if (!res || stack.length === 0 || !Script.bool(stack.pop()))
return false;
if ((flags & constants.flags.VERIFY_WITNESS) && redeem.isWitnessProgram()) {
hadWitness = true;
// Input script must be exactly one push of the redeem script.
if (!(input.code.length === 1 && utils.isEqual(input.code[0], raw)))
return false;
// Verify the program in the redeem script
if (!Script.verifyProgram(witness, redeem, flags, tx, i))
return false;
// Force a cleanstack
stack.length = 0;
}
}
// Ensure there is nothing left on the stack
if (flags & constants.flags.VERIFY_CLEANSTACK) {
assert((flags & constants.flags.VERIFY_P2SH) !== 0);
// assert((flags & constants.flags.VERIFY_WITNESS) !== 0);
if (stack.length !== 0)
return false;
}
// If we had a witness but no witness program, fail.
if (flags & constants.flags.VERIFY_WITNESS) {
assert((flags & constants.flags.VERIFY_P2SH) !== 0);
if (!hadWitness && witness.length > 0)
return false;
}
return true;
};
Script.verifyProgram = function verifyProgram(witness, output, flags, tx, i) {
var program, witnessScript, redeem, stack, j, res;
assert((flags & constants.flags.VERIFY_WITNESS) !== 0);
assert(output.isWitnessProgram());
program = output.getWitnessProgram();
// Failure on version=0 (bad program data length)
if (!program.type) {
utils.debug('Malformed witness program.');
return false;
}
if (program.version > 0) {
utils.debug('Unknown witness program version: %s', program.version);
// Anyone can spend (we can return true here
// if we want to always relay these transactions).
// Otherwise, if we want to act like an "old"
// implementation and only accept them in blocks,
// we can use the regalar output script which will
// succeed in a block, but fail in the mempool
// due to VERIFY_CLEANSTACK.
if (flags & constants.flags.VERIFY_DISCOURAGE_UPGRADABLE_WITNESS_PROGRAM)
return false;
return true;
}
stack = witness.toStack();
if (program.type === 'witnesspubkeyhash') {
if (stack.length !== 2)
return false;
redeem = Script.createPubkeyhash(program.data);
} else if (program.type === 'witnessscripthash') {
if (stack.length === 0)
return false;
witnessScript = stack.pop();
if (!utils.isEqual(utils.sha256(witnessScript), program.data))
return false;
redeem = new Script(witnessScript);
} else {
assert(false);
}
for (j = 0; j < stack.length; j++) {
if (stack.get(j).length > constants.script.maxSize)
return false;
}
res = redeem.execute(stack, flags, tx, i, 1);
// Verify the script did not fail as well as the stack values
if (!res || stack.length === 0 || !Script.bool(stack.pop()))
return false;
// Witnesses always require cleanstack
if (stack.length !== 0)
return false;
return true;
};
Script.concat = function concat(scripts) {
var code = [];
var i;
code = code.concat(scripts[0].code);
for (i = 1; i < scripts.length; i++) {
code.push(opcodes.OP_CODESEPARATOR);
code = code.concat(scripts[i].code);
}
return code;
};
Script.checksig = function checksig(msg, sig, key, flags) {
var historical = false;
if (flags == null)
flags = constants.flags.STANDARD_VERIFY_FLAGS;
if (!Buffer.isBuffer(sig))
return false;
if (sig.length === 0)
return false;
// Attempt to normalize the signature
// length before passing to elliptic.
// Note: We only do this for historical data!
// https://github.com/indutny/elliptic/issues/78
if (!((flags & constants.flags.VERIFY_DERSIG)
|| (flags & constants.flags.VERIFY_LOW_S)
|| (flags & constants.flags.VERIFY_STRICTENC))) {
historical = true;
}
return bcoin.ec.verify(msg, sig.slice(0, -1), key, historical);
};
Script.sign = function sign(msg, key, type) {
var sig = bcoin.ec.sign(msg, key);
// Add the sighash type as a single byte
// to the signature.
sig = Buffer.concat([sig, new Buffer([type])]);
return sig;
};
Script.decode = function decode(buf) {
var code = [];
var off = 0;
var op, size;
assert(Buffer.isBuffer(buf));
// NOTE: We can't use a BufferReader here since
// script parsing was originally non-strict/ridiculous.
// Something could do a direct push of 30 bytes with
// only 20 bytes after it.
// NOTE 2: We use reference Buffer slices here. Larger
// buffer slices should _never_ be passed in here.
while (off < buf.length) {
op = buf[off++];
// Direct Push
// Next `op` bytes should be pushed to stack
if (op >= 0x01 && op <= 0x4b) {
code.push(buf.slice(off, off + op));
off += op;
if (off > buf.length) {
utils.hidden(code[code.length - 1], 'pushdata', {
opcode: null,
size: op
});
}
continue;
}
if (off >= buf.length) {
code.push(op);
continue;
}
if (op === opcodes.OP_PUSHDATA1) {
size = buf[off];
off += 1;
code.push(buf.slice(off, off + size));
off += size;
if (size <= 0x4b || off > buf.length) {
utils.hidden(code[code.length - 1], 'pushdata', {
opcode: op,
size: size
});
}
} else if (op === opcodes.OP_PUSHDATA2) {
size = utils.readU16(buf, off);
off += 2;
code.push(buf.slice(off, off + size));
off += size;
if (size <= 0xff || off > buf.length) {
utils.hidden(code[code.length - 1], 'pushdata', {
opcode: op,
size: size
});
}
} else if (op === opcodes.OP_PUSHDATA4) {
size = utils.readU32(buf, off);
off += 4;
code.push(buf.slice(off, off + size));
off += size;
if (size <= 0xffff || off > buf.length) {
utils.hidden(code[code.length - 1], 'pushdata', {
opcode: op,
size: size
});
}
} else {
code.push(op);
}
}
return code;
};
Script.encode = function encode(code) {
var p = new BufferWriter();
var i = 0;
var op;
assert(Array.isArray(code));
for (i = 0; i < code.length; i++) {
op = code[i];
// Push value to stack
if (Buffer.isBuffer(op)) {
// Check for nonstandard pushdatas that
// may have been decoded from before.
if (op.pushdata) {
if (op.pushdata.opcode === null) {
p.writeU8(op.pushdata.size);
p.writeBytes(op);
} else if (op.pushdata.opcode === opcodes.OP_PUSHDATA1) {
p.writeU8(opcodes.OP_PUSHDATA1);
p.writeU8(op.pushdata.size);
p.writeBytes(op);
} else if (op.pushdata.opcode === opcodes.OP_PUSHDATA2) {
p.writeU8(opcodes.OP_PUSHDATA2);
p.writeU16(op.pushdata.size);
p.writeBytes(op);
} else if (op.pushdata.opcode === opcodes.OP_PUSHDATA4) {
p.writeU8(opcodes.OP_PUSHDATA4);
p.writeU32(op.pushdata.size);
p.writeBytes(op);
}
continue;
}
// Standard minimaldata encoding
if (op.length === 0) {
p.writeU8(opcodes.OP_0);
} else if (op.length <= 0x4b) {
p.writeU8(op.length);
p.writeBytes(op);
} else if (op.length <= 0xff) {
p.writeU8(opcodes.OP_PUSHDATA1);
p.writeU8(op.length);
p.writeBytes(op);
} else if (op.length <= 0xffff) {
p.writeU8(opcodes.OP_PUSHDATA2);
p.writeU16(op.length);
p.writeBytes(op);
} else {
p.writeU8(opcodes.OP_PUSHDATA4);
p.writeU32(op.length);
p.writeBytes(op);
}
continue;
}
assert(typeof op === 'number');
p.writeU8(op);
}
return p.render();
};
Script.isScript = function isScript(obj) {
return obj
&& Array.isArray(obj.code)
&& typeof obj.getSubscript === 'function';
};
/**
* ScriptError
*/
function ScriptError(msg, op, ip) {
Error.call(this);
if (Error.captureStackTrace)
Error.captureStackTrace(this, ScriptError);
this.type = 'ScriptError';
if (Buffer.isBuffer(op))
op = 'PUSHDATA[' + op.length + ']';
if (op || ip != null) {
msg += '(';
if (op) {
op = constants.opcodesByVal[op] || op;
msg += 'op=' + op;
if (ip != null)
msg += ', ';
}
if (ip != null)
msg += 'ip=' + ip;
}
this.message = msg;
this.op = op;
this.ip = ip;
}
utils.inherits(ScriptError, Error);
Script.witness = Witness;
Script.stack = Stack;
Script.error = ScriptError;
module.exports = Script;