node-libcoin/ScriptInterpreter.js at master · leostera/node-libcoin · GitHub

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require('classtool');

function spec(b) {

var assert = require('assert');

var config = b.config || require('./config');

var log = b.log || require('./util/log');

var Opcode = require('./Opcode').class();

// Make opcodes available as pseudo-constants

for (var i in Opcode.map) {

eval(i + " = " + Opcode.map[i] + ";");

}

var bignum = b.bignum || require('bignum');

var Util = b.Util || require('./util/util');

var Script = require('./Script').class();

function ScriptInterpreter() {

this.stack = [];

this.disableUnsafeOpcodes = true;

};

ScriptInterpreter.prototype.eval = function eval(script, tx, inIndex, hashType, callback)

{

if ("function" !== typeof callback) {

throw new Error("ScriptInterpreter.eval() requires a callback");

}

var pc = 0;

var execStack = [];

var altStack = [];

var hashStart = 0;

var opCount = 0;

if (script.buffer.length > 10000) {

callback(new Error("Oversized script (> 10k bytes)"));

return this;

}

// Start execution by running the first step

executeStep.call(this, callback);

function executeStep(cb) {

// Once all chunks have been processed, execution ends

if (pc >= script.chunks.length) {

// Execution stack must be empty at the end of the script

if (execStack.length) {

cb(new Error("Execution stack ended non-empty"));

return;

}

// Execution successful (Note that we still have to check whether the

// final stack contains a truthy value.)

cb(null);

return;

}

try {

// The execution bit is true if there are no "false" values in the

// execution stack. (A "false" value indicates that we're in the

// inactive branch of an if statement.)

var exec = !~execStack.indexOf(false);

var opcode = script.chunks[pc++];

if (opcode.length > 520) {

throw new Error("Max push value size exceeded (>520)");

}

if (opcode > OP_16 && ++opCount > 201) {

throw new Error("Opcode limit exceeded (>200)");

}

if (this.disableUnsafeOpcodes &&

"number" === typeof opcode &&

(opcode === OP_CAT ||

opcode === OP_SUBSTR ||

opcode === OP_LEFT ||

opcode === OP_RIGHT ||

opcode === OP_INVERT ||

opcode === OP_AND ||

opcode === OP_OR ||

opcode === OP_XOR ||

opcode === OP_2MUL ||

opcode === OP_2DIV ||

opcode === OP_MUL ||

opcode === OP_DIV ||

opcode === OP_MOD ||

opcode === OP_LSHIFT ||

opcode === OP_RSHIFT)) {

throw new Error("Encountered a disabled opcode");

}

if (exec && Buffer.isBuffer(opcode))

this.stack.push(opcode);

else if (exec || (OP_IF <= opcode && opcode <= OP_ENDIF))

switch (opcode) {

case OP_0:

this.stack.push(new Buffer([]));

break;

case OP_1NEGATE:

case OP_1:

case OP_2:

case OP_3:

case OP_4:

case OP_5:

case OP_6:

case OP_7:

case OP_8:

case OP_9:

case OP_10:

case OP_11:

case OP_12:

case OP_13:

case OP_14:

case OP_15:

case OP_16:

this.stack.push(bigintToBuffer(opcode - OP_1 + 1));

break;

case OP_NOP:

case OP_NOP1: case OP_NOP2: case OP_NOP3: case OP_NOP4: case OP_NOP5:

case OP_NOP6: case OP_NOP7: case OP_NOP8: case OP_NOP9: case OP_NOP10:

break;

case OP_IF:

case OP_NOTIF:

// <expression> if [statements] [else [statements]] endif

var value = false;

if (exec) {

value = castBool(this.stackPop());

if (opcode === OP_NOTIF) {

value = !value;

}

execStack.push(value);

break;

case OP_ELSE:

if (execStack.length < 1) {

throw new Error("Unmatched OP_ELSE");

}

execStack[execStack.length-1] = !execStack[execStack.length-1];

break;

case OP_ENDIF:

if (execStack.length < 1) {

throw new Error("Unmatched OP_ENDIF");

}

execStack.pop();

break;

case OP_VERIFY:

var value = castBool(this.stackTop());

if (value) {

this.stackPop();

} else {

throw new Error("OP_VERIFY negative");

}

break;

case OP_RETURN:

throw new Error("OP_RETURN");

case OP_TOALTSTACK:

altStack.push(this.stackPop());

break;

case OP_FROMALTSTACK:

if (altStack.length < 1) {

throw new Error("OP_FROMALTSTACK with alt stack empty");

}

this.stack.push(altStack.pop());

break;

case OP_2DROP:

// (x1 x2 -- )

this.stackPop();

break;

case OP_2DUP:

// (x1 x2 -- x1 x2 x1 x2)

var v1 = this.stackTop(2);

var v2 = this.stackTop(1);

this.stack.push(v1);

this.stack.push(v2);

break;

case OP_3DUP:

// (x1 x2 -- x1 x2 x1 x2)

var v1 = this.stackTop(3);

var v2 = this.stackTop(2);

var v3 = this.stackTop(1);

this.stack.push(v1);

this.stack.push(v2);

this.stack.push(v3);

break;

case OP_2OVER:

// (x1 x2 x3 x4 -- x1 x2 x3 x4 x1 x2)

var v1 = this.stackTop(4);

var v2 = this.stackTop(3);

this.stack.push(v1);

this.stack.push(v2);

break;

case OP_2ROT:

// (x1 x2 x3 x4 x5 x6 -- x3 x4 x5 x6 x1 x2)

var v1 = this.stackTop(6);

var v2 = this.stackTop(5);

this.stack.splice(this.stack.length - 6, 2);

this.stack.push(v1);

this.stack.push(v2);

break;

case OP_2SWAP:

// (x1 x2 x3 x4 -- x3 x4 x1 x2)

this.stackSwap(4, 2);

this.stackSwap(3, 1);

break;

case OP_IFDUP:

// (x - 0 | x x)

var value = this.stackTop();

if (castBool(value)) {

this.stack.push(value);

}

break;

case OP_DEPTH:

// -- stacksize

var value = bignum(this.stack.length);

this.stack.push(bigintToBuffer(value));

break;

case OP_DROP:

// (x -- )

this.stackPop();

break;

case OP_DUP:

// (x -- x x)

this.stack.push(this.stackTop());

break;

case OP_NIP:

// (x1 x2 -- x2)

if (this.stack.length < 2) {

throw new Error("OP_NIP insufficient stack size");

}

this.stack.splice(this.stack.length - 2, 1);

break;

case OP_OVER:

// (x1 x2 -- x1 x2 x1)

this.stack.push(this.stackTop(2));

break;

case OP_PICK:

case OP_ROLL:

// (xn ... x2 x1 x0 n - xn ... x2 x1 x0 xn)

// (xn ... x2 x1 x0 n - ... x2 x1 x0 xn)

var n = castInt(this.stackPop());

if (n < 0 || n >= this.stack.length) {

throw new Error("OP_PICK/OP_ROLL insufficient stack size");

}

var value = this.stackTop(n+1);

if (opcode === OP_ROLL) {

this.stack.splice(this.stack.length - n - 1, 1);

}

this.stack.push(value);

break;

case OP_ROT:

// (x1 x2 x3 -- x2 x3 x1)

// x2 x1 x3 after first swap

// x2 x3 x1 after second swap

this.stackSwap(3, 2);

this.stackSwap(2, 1);

break;

case OP_SWAP:

// (x1 x2 -- x2 x1)

this.stackSwap(2, 1);

break;

case OP_TUCK:

// (x1 x2 -- x2 x1 x2)

if (this.stack.length < 2) {

throw new Error("OP_TUCK insufficient stack size");

}

this.stack.splice(this.stack.length - 2, 0, this.stackTop());

break;

case OP_CAT:

// (x1 x2 -- out)

var v1 = this.stackTop(2);

var v2 = this.stackTop(1);

this.stackPop();

this.stack.push(v1.concat(v2));

break;

case OP_SUBSTR:

// (in begin size -- out)

var buf = this.stackTop(3);

var start = castInt(this.stackTop(2));

var len = castInt(this.stackTop(1));

if (start < 0 || len < 0) {

throw new Error("OP_SUBSTR start < 0 or len < 0");

}

if ((start + len) >= buf.length) {

throw new Error("OP_SUBSTR range out of bounds");

}

this.stackPop();

this.stack[this.stack.length-1] = buf.slice(start, start + len);

break;

case OP_LEFT:

case OP_RIGHT:

// (in size -- out)

var buf = this.stackTop(2);

var size = castInt(this.stackTop(1));

if (size < 0) {

throw new Error("OP_LEFT/OP_RIGHT size < 0");

}

if (size > buf.length) {

size = buf.length;

}

this.stackPop();

if (opcode === OP_LEFT) {

this.stack[this.stack.length-1] = buf.slice(0, size);

} else {

this.stack[this.stack.length-1] = buf.slice(buf.length - size);

}

break;

case OP_SIZE:

// (in -- in size)

var value = bignum(this.stackTop().length);

this.stack.push(bigintToBuffer(value));

break;

case OP_INVERT:

// (in - out)

var buf = this.stackTop();

for (var i = 0, l = buf.length; i < l; i++) {

buf[i] = ~buf[i];

}

break;

case OP_AND:

case OP_OR:

case OP_XOR:

// (x1 x2 - out)

var v1 = this.stackTop(2);

var v2 = this.stackTop(1);

this.stackPop();

var out = new Buffer(Math.max(v1.length, v2.length));

if (opcode === OP_AND) {

for (var i = 0, l = out.length; i < l; i++) {

out[i] = v1[i] & v2[i];

}

} else if (opcode === OP_OR) {

for (var i = 0, l = out.length; i < l; i++) {

out[i] = v1[i] | v2[i];

}

} else if (opcode === OP_XOR) {

for (var i = 0, l = out.length; i < l; i++) {

out[i] = v1[i] ^ v2[i];

}

this.stack.push(out);

break;

case OP_EQUAL:

case OP_EQUALVERIFY:

//case OP_NOTEQUAL: // use OP_NUMNOTEQUAL

// (x1 x2 - bool)

var v1 = this.stackTop(2);

var v2 = this.stackTop(1);

var value = v1.compare(v2) == 0;

// OP_NOTEQUAL is disabled because it would be too easy to say

// something like n != 1 and have some wiseguy pass in 1 with extra

// zero bytes after it (numerically, 0x01 == 0x0001 == 0x000001)

//if (opcode == OP_NOTEQUAL)

// fEqual = !fEqual;

this.stackPop();

this.stack.push(new Buffer([value ? 1 : 0]));

if (opcode === OP_EQUALVERIFY) {

if (value) {

this.stackPop();

} else {

throw new Error("OP_EQUALVERIFY negative");

}

break;

case OP_1ADD:

case OP_1SUB:

case OP_2MUL:

case OP_2DIV:

case OP_NEGATE:

case OP_ABS:

case OP_NOT:

case OP_0NOTEQUAL:

// (in -- out)

var num = castBigint(this.stackTop());

switch (opcode) {

case OP_1ADD: num = num.add(bignum(1)); break;

case OP_1SUB: num = num.sub(bignum(1)); break;

case OP_2MUL: num = num.mul(bignum(2)); break;

case OP_2DIV: num = num.div(bignum(2)); break;

case OP_NEGATE: num = num.neg(); break;

case OP_ABS: num = num.abs(); break;

case OP_NOT: num = bignum(num.cmp(0) == 0 ? 1 : 0); break;

case OP_0NOTEQUAL: num = bignum(num.cmp(0) == 0 ? 0 : 1); break;

}

this.stack[this.stack.length-1] = bigintToBuffer(num);

break;

case OP_ADD:

case OP_SUB:

case OP_MUL:

case OP_DIV:

case OP_MOD:

case OP_LSHIFT:

case OP_RSHIFT:

case OP_BOOLAND:

case OP_BOOLOR:

case OP_NUMEQUAL:

case OP_NUMEQUALVERIFY:

case OP_NUMNOTEQUAL:

case OP_LESSTHAN:

case OP_GREATERTHAN:

case OP_LESSTHANOREQUAL:

case OP_GREATERTHANOREQUAL:

case OP_MIN:

case OP_MAX:

// (x1 x2 -- out)

var v1 = castBigint(this.stackTop(2));

var v2 = castBigint(this.stackTop(1));

var num;

switch (opcode) {

case OP_ADD: num = v1.add(v2); break;

case OP_SUB: num = v1.sub(v2); break;

case OP_MUL: num = v1.mul(v2); break;

case OP_DIV: num = v1.div(v2); break;

case OP_MOD: num = v1.mod(v2); break;

case OP_LSHIFT:

if (v2.cmp(0) < 0 || v2.cmp(2048) > 0) {

throw new Error("OP_LSHIFT parameter out of bounds");

}

num = v1.shiftLeft(v2);

break;

case OP_RSHIFT:

if (v2.cmp(0) < 0 || v2.cmp(2048) > 0) {

throw new Error("OP_RSHIFT parameter out of bounds");

}

num = v1.shiftRight(v2);

break;

case OP_BOOLAND:

num = bignum((v1.cmp(0) != 0 && v2.cmp(0) != 0) ? 1 : 0);

break;

case OP_BOOLOR:

num = bignum((v1.cmp(0) != 0 || v2.cmp(0) != 0) ? 1 : 0);

break;

case OP_NUMEQUAL:

case OP_NUMEQUALVERIFY:

num = bignum(v1.cmp(v2) == 0 ? 1 : 0);

break;

case OP_NUMNOTEQUAL:;

num = bignum(v1.cmp(v2) != 0 ? 1 : 0);

break;

case OP_LESSTHAN:

num = bignum(v1.lt(v2) ? 1 : 0);

break;

case OP_GREATERTHAN:

num = bignum(v1.gt(v2) ? 1 : 0);

break;

case OP_LESSTHANOREQUAL:

num = bignum(v1.gt(v2) ? 0 : 1);

break;

case OP_GREATERTHANOREQUAL:

num = bignum(v1.lt(v2) ? 0 : 1);

break;

case OP_MIN: num = (v1.lt(v2) ? v1 : v2); break;

case OP_MAX: num = (v1.gt(v2) ? v1 : v2); break;

}

this.stackPop();

this.stack.push(bigintToBuffer(num));

if (opcode === OP_NUMEQUALVERIFY) {

if (castBool(this.stackTop())) {

this.stackPop();

} else {

throw new Error("OP_NUMEQUALVERIFY negative");

}

break;

case OP_WITHIN:

// (x min max -- out)

var v1 = castBigint(this.stackTop(3));

var v2 = castBigint(this.stackTop(2));

var v3 = castBigint(this.stackTop(1));

this.stackPop();

var value = v1.cmp(v2) >= 0 && v1.cmp(v3) < 0;

this.stack.push(bigintToBuffer(value ? 1 : 0));

break;

case OP_RIPEMD160:

case OP_SHA1:

case OP_SHA256:

case OP_HASH160:

case OP_HASH256:

// (in -- hash)

var value = this.stackPop();

var hash;

if (opcode === OP_RIPEMD160) {

hash = Util.ripe160(value);

} else if (opcode === OP_SHA1) {

hash = Util.sha1(value);

} else if (opcode === OP_SHA256) {

hash = Util.sha256(value);

} else if (opcode === OP_HASH160) {

hash = Util.sha256ripe160(value);

} else if (opcode === OP_HASH256) {

hash = Util.twoSha256(value);

}

this.stack.push(hash);

break;

case OP_CODESEPARATOR:

// Hash starts after the code separator

hashStart = pc;

break;

case OP_CHECKSIG:

case OP_CHECKSIGVERIFY:

// (sig pubkey -- bool)

var sig = this.stackTop(2);

var pubkey = this.stackTop(1);

// Get the part of this script since the last OP_CODESEPARATOR

var scriptChunks = script.chunks.slice(hashStart);

// Convert to binary

var scriptCode = Script.fromChunks(scriptChunks);

// Remove signature if present (a signature can't sign itself)

scriptCode.findAndDelete(sig);

// Verify signature

checkSig(sig, pubkey, scriptCode, tx, inIndex, hashType, function (e, result) {

try {

var success;

if (e) {

// We intentionally ignore errors during signature verification and

// treat these cases as an invalid signature.

success = false;

} else {

success = result;

}

// Update stack

this.stackPop();

this.stack.push(new Buffer([success ? 1 : 0]));

if (opcode === OP_CHECKSIGVERIFY) {

if (success) {

this.stackPop();

} else {

throw new Error("OP_CHECKSIGVERIFY negative");

}

// Run next step

executeStep.call(this, cb);

} catch(e) {

cb(e);

}

}.bind(this));

// Note that for asynchronous opcodes we have to return here to prevent

// the next opcode from being executed.

return;

case OP_CHECKMULTISIG:

case OP_CHECKMULTISIGVERIFY:

// ([sig ...] num_of_signatures [pubkey ...] num_of_pubkeys -- bool)

var keysCount = castInt(this.stackPop());

if (keysCount < 0 || keysCount > 20) {

throw new Error("OP_CHECKMULTISIG keysCount out of bounds");

}

opCount += keysCount;

if (opCount > 201) {

throw new Error("Opcode limit exceeded (>200)");

}

var keys = [];

for (var i = 0, l = keysCount; i < l; i++) {

keys.push(this.stackPop());

}

var sigsCount = castInt(this.stackPop());

if (sigsCount < 0 || sigsCount > keysCount) {

throw new Error("OP_CHECKMULTISIG sigsCount out of bounds");

}

var sigs = [];

for (var i = 0, l = sigsCount; i < l; i++) {

sigs.push(this.stackPop());

}

// The original client has a bug where it pops an extra element off the

// stack. It can't be fixed without causing a chain split and we need to

// imitate this behavior as well.

this.stackPop();

// Get the part of this script since the last OP_CODESEPARATOR

var scriptChunks = script.chunks.slice(hashStart);

// Convert to binary

var scriptCode = Script.fromChunks(scriptChunks);

// Drop the signatures, since a signature can't sign itself

sigs.forEach(function (sig) {

scriptCode.findAndDelete(sig);

});

var success = true, isig = 0, ikey = 0;

checkMultiSigStep.call(this);

function checkMultiSigStep() {

try {

if (success && sigsCount > 0) {

var sig = sigs[isig];

var key = keys[ikey];

checkSig(sig, key, scriptCode, tx, inIndex, hashType, function (e, result) {

try {

if (!e && result) {

isig++;

sigsCount--;

} else {

ikey++;

keysCount--;

// If there are more signatures than keys left, then too many

// signatures have failed

if (sigsCount > keysCount) {

success = false;

}

checkMultiSigStep.call(this);

} catch (e) {

cb(e);

}

}.bind(this));

} else {

this.stack.push(new Buffer([success ? 1 : 0]));

if (opcode === OP_CHECKMULTISIGVERIFY) {

if (success) {

this.stackPop();

} else {

throw new Error("OP_CHECKMULTISIGVERIFY negative");

}

// Run next step

executeStep.call(this, cb);

}

} catch(e) {

cb(e);

}

};

// Note that for asynchronous opcodes we have to return here to prevent

// the next opcode from being executed.

return;

default:

throw new Error("Unknown opcode encountered");

}

// Size limits

if ((this.stack.length + altStack.length) > 1000) {

throw new Error("Maximum stack size exceeded");

}

// Run next step

if (pc % 100) {

// V8 allows for much deeper stacks than Bitcoin's scripting language,

// but just to be safe, we'll reset the stack every 100 steps

process.nextTick(executeStep.bind(this, cb));

} else {

executeStep.call(this, cb);

}

} catch (e) {

log.debug("Script aborted: "+

(e.message ? e : e));

cb(e);

}

};

ScriptInterpreter.prototype.evalTwo =

function evalTwo(scriptSig, scriptPubkey, tx, n, hashType, callback)

{

var self = this;

self.eval(scriptSig, tx, n, hashType, function (e) {

if (e) {

callback(e)

return;

}

self.eval(scriptPubkey, tx, n, hashType, callback);

});

};

/**

* Get the top element of the stack.

* Using the offset parameter this function can also access lower elements

* from the stack.

ScriptInterpreter.prototype.stackTop = function stackTop(offset) {

offset = +offset || 1;

if (offset < 1) offset = 1;

if (offset > this.stack.length) {

throw new Error('ScriptInterpreter.stackTop(): Stack underrun');

}

return this.stack[this.stack.length-offset];

};

ScriptInterpreter.prototype.stackBack = function stackBack()

{

return this.stack[-1];

};

/**

* Pop the top element off the stack and return it.

ScriptInterpreter.prototype.stackPop = function stackPop() {

if (this.stack.length < 1) {

throw new Error('ScriptInterpreter.stackTop(): Stack underrun');

}

return this.stack.pop();

};

ScriptInterpreter.prototype.stackSwap = function stackSwap(a, b) {

if (this.stack.length < a || this.stack.length < b) {

throw new Error('ScriptInterpreter.stackTop(): Stack underrun');

}

var s = this.stack,

l = s.length;

var tmp = s[l - a];

s[l - a] = s[l - b];

s[l - b] = tmp;

};

/**

* Returns a version of the stack with only primitive types.

* The return value is an array. Any single byte buffer is converted to an

* integer. Any longer Buffer is converted to a hex string.

ScriptInterpreter.prototype.getPrimitiveStack = function getPrimitiveStack() {

return this.stack.map(function (entry) {

if (entry.length > 2) {

return entry.slice(0).toHex();

}

var num = castBigint(entry);

if (num.cmp(-128) >= 0 && num.cmp(127) <= 0) {

return num.toNumber();

} else {

return entry.slice(0).toHex();

}

});

};

var castBool = ScriptInterpreter.castBool = function castBool(v) {

for (var i = 0, l = v.length; i < l; i++) {

if (v[i] != 0) {

// Negative zero is still zero

if (i == (l-1) && v[i] == 0x80) {

return false;

}

return true;

}

return false;

};

var castInt = ScriptInterpreter.castInt = function castInt(v) {

return castBigint(v).toNumber();

};

var castBigint = ScriptInterpreter.castBigint = function castBigint(v) {

if (!v.length) {

return bignum(0);

}

// Arithmetic operands must be in range [-2^31...2^31]

if (v.length > 4) {

throw new Error("Bigint cast overflow (> 4 bytes)");

}

var w = new Buffer(v.length);

v.copy(w);

w.reverse();

if (w[0] & 0x80) {

w[0] &= 0x7f;

return bignum.fromBuffer(w).neg();

} else {

// Positive number

return bignum.fromBuffer(w);

}

};

var bigintToBuffer = ScriptInterpreter.bigintToBuffer = function bigintToBuffer(v) {

if ("number" === typeof v) {

v = bignum(v);

}

var b,c;

var cmp = v.cmp(0);

if (cmp > 0) {

b = v.toBuffer();

if (b[0] & 0x80) {

c = new Buffer(b.length + 1);

b.copy(c, 1);

c[0] = 0;

return c.reverse();

} else {

return b.reverse();

}

} else if (cmp == 0) {

return new Buffer([]);

} else {

b = v.neg().toBuffer();

if (b[0] & 0x80) {

c = new Buffer(b.length + 1);

b.copy(c, 1);

c[0] = 0x80;

return c.reverse();

} else {

b[0] |= 0x80;

return b.reverse();

}

};

ScriptInterpreter.prototype.getResult = function getResult() {

if (this.stack.length === 0) {

throw new Error("Empty stack after script evaluation");

}

return castBool(this.stack[this.stack.length-1]);

};

ScriptInterpreter.verify =

function verify(scriptSig, scriptPubKey, txTo, n, hashType, callback)

{

if ("function" !== typeof callback) {

throw new Error("ScriptInterpreter.verify() requires a callback");

}

// Create execution environment

var si = new ScriptInterpreter();

// Evaluate scripts

si.evalTwo(scriptSig, scriptPubKey, txTo, n, hashType, function (err) {

if (err) {

callback(err);

return;

}

// Cast result to bool

try {

var result = si.getResult();

} catch (err) {

callback(err);

return;

}

callback(null, result);

});

return si;

};

function verifyStep4(scriptSig, scriptPubKey, txTo, nIn,

hashType, opts, callback, si, siCopy)

{

if (siCopy.stack.length == 0) {

callback(null, false);

return;

}

callback(null, castBool(siCopy.stackBack()));

}

function verifyStep3(scriptSig, scriptPubKey, txTo, nIn,

hashType, opts, callback, si, siCopy)

{

if (si.stack.length == 0) {

callback(null, false);

return;

}

if (castBool(si.stackBack()) == false) {

callback(null, false);

return;

}

// if not P2SH, we're done

if (!opts.verifyP2SH || !scriptPubKey.isP2SH()) {

callback(null, true);

return;

}

if (!scriptSig.isPushOnly()) {

callback(null, false);

return;

}

assert.notEqual(siCopy.length, 0);

var subscript = new Script(siCopy.stackPop());

ok = true;

siCopy.eval(subscript, txTo, nIn, hashType, function (err) {

if (err)

callback(err);

else

verifyStep4(scriptSig, scriptPubKey, txTo, nIn,

hashType, opts, callback, si, siCopy);

});

}

function verifyStep2(scriptSig, scriptPubKey, txTo, nIn,

hashType, opts, callback, si, siCopy)

{

if (opts.verifyP2SH) {

si.stack.forEach(function(item) {

siCopy.stack.push(item);

});

}

si.eval(scriptPubKey, txTo, nIn, hashType, function (err) {

if (err)

callback(err);

else

verifyStep3(scriptSig, scriptPubKey, txTo, nIn,

hashType, opts, callback, si, siCopy);

});

}

ScriptInterpreter.verifyFull =

function verifyFull(scriptSig, scriptPubKey, txTo, nIn, hashType,

opts, callback)

{

var si = new ScriptInterpreter();

var siCopy = new ScriptInterpreter();

si.eval(scriptSig, txTo, nIn, hashType, function (err) {

if (err)

callback(err);

else

verifyStep2(scriptSig, scriptPubKey, txTo, nIn,

hashType, opts, callback, si, siCopy);

});

};

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node-libcoin/ScriptInterpreter.js at master · leostera/node-libcoin · GitHub

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