Daniel Cousens
8 years ago
committed by
Daniel Cousens
3 changed files with 62 additions and 52 deletions
@ -0,0 +1,58 @@ |
|||
/* global describe, it */ |
|||
|
|||
var assert = require('assert') |
|||
var bigi = require('bigi') |
|||
var bitcoin = require('../../') |
|||
var crypto = require('crypto') |
|||
|
|||
var ecurve = require('ecurve') |
|||
var secp256k1 = ecurve.getCurveByName('secp256k1') |
|||
|
|||
describe('bitcoinjs-lib (BIP32)', function () { |
|||
it('can recover a BIP32 parent private key from the parent public key, and a derived, non-hardened child private key', function () { |
|||
function recoverParent (master, child) { |
|||
assert(!master.keyPair.d, 'You already have the parent private key') |
|||
assert(child.keyPair.d, 'Missing child private key') |
|||
|
|||
var curve = secp256k1 |
|||
var QP = master.keyPair.Q |
|||
var serQP = master.keyPair.getPublicKeyBuffer() |
|||
|
|||
var d1 = child.keyPair.d |
|||
var d2 |
|||
var data = new Buffer(37) |
|||
serQP.copy(data, 0) |
|||
|
|||
// search index space until we find it
|
|||
for (var i = 0; i < bitcoin.HDNode.HIGHEST_BIT; ++i) { |
|||
data.writeUInt32BE(i, 33) |
|||
|
|||
// calculate I
|
|||
var I = crypto.createHmac('sha512', master.chainCode).update(data).digest() |
|||
var IL = I.slice(0, 32) |
|||
var pIL = bigi.fromBuffer(IL) |
|||
|
|||
// See hdnode.js:273 to understand
|
|||
d2 = d1.subtract(pIL).mod(curve.n) |
|||
|
|||
var Qp = new bitcoin.ECPair(d2).Q |
|||
if (Qp.equals(QP)) break |
|||
} |
|||
|
|||
var node = new bitcoin.HDNode(new bitcoin.ECPair(d2), master.chainCode, master.network) |
|||
node.depth = master.depth |
|||
node.index = master.index |
|||
node.masterFingerprint = master.masterFingerprint |
|||
return node |
|||
} |
|||
|
|||
var seed = crypto.randomBytes(32) |
|||
var master = bitcoin.HDNode.fromSeedBuffer(seed) |
|||
var child = master.derive(6) // m/6
|
|||
|
|||
// now for the recovery
|
|||
var neuteredMaster = master.neutered() |
|||
var recovered = recoverParent(neuteredMaster, child) |
|||
assert.strictEqual(recovered.toBase58(), master.toBase58()) |
|||
}) |
|||
}) |
Loading…
Reference in new issue