stealth: add dual key example

This commit is contained in:
Daniel Cousens 2016-12-10 13:52:08 +11:00 committed by Daniel Cousens
parent 1304527c1d
commit b4062d56d1

View file

@ -12,10 +12,8 @@ var n = secp256k1.n
// vG = (dG * sha256(e * dG)G)
function stealthSend (e, Q) {
var eQ = Q.multiply(e) // shared secret
var c = bigi.fromBuffer(bitcoin.crypto.sha256(eQ.getEncoded()))
var cG = G.multiply(c)
var vG = new bitcoin.ECPair(null, Q.add(cG))
return vG
@ -24,7 +22,6 @@ function stealthSend (e, Q) {
// v = (d + sha256(eG * d))
function stealthReceive (d, eG) {
var eQ = eG.multiply(d) // shared secret
var c = bigi.fromBuffer(bitcoin.crypto.sha256(eQ.getEncoded()))
var v = new bitcoin.ECPair(d.add(c).mod(n))
@ -40,6 +37,34 @@ function stealthRecoverLeaked (v, e, Q) {
return d
}
// vG = (rG * (dG * sha256(e * dG)G))
function stealthDualSend (e, R, Q) {
var eQ = Q.multiply(e) // shared secret
var c = bigi.fromBuffer(bitcoin.crypto.sha256(eQ.getEncoded()))
var cG = G.multiply(c)
var vG = new bitcoin.ECPair(null, R.add(Q.add(cG)))
return vG
}
// vG = (rG * (d + sha256(eG * d))G)
function stealthDualScan (d, R, eG) {
var eQ = eG.multiply(d) // shared secret
var c = bigi.fromBuffer(bitcoin.crypto.sha256(eQ.getEncoded()))
var vG = new bitcoin.ECPair(null, R.add(G.multiply(d.add(c).mod(n))))
return vG
}
// v = (r + d + sha256(eG * d))
function stealthDualReceive (d, r, eG) {
var eQ = eG.multiply(d) // shared secret
var c = bigi.fromBuffer(bitcoin.crypto.sha256(eQ.getEncoded()))
var v = new bitcoin.ECPair(r.add(d).add(c).mod(n))
return v
}
describe('bitcoinjs-lib (crypto)', function () {
it('can generate a single-key stealth address', function () {
// XXX: should be randomly generated, see next test for example
@ -93,6 +118,26 @@ describe('bitcoinjs-lib (crypto)', function () {
assert.equal(leaked.toWIF(), recipient.toWIF())
})
// TODO
it.skip('can generate a dual-key stealth address', function () {})
it('can generate a dual-key stealth address (randomly)', function () {
// XXX: should be randomly generated, see next test for example
var recipient = bitcoin.ECPair.fromWIF('5KYZdUEo39z3FPrtuX2QbbwGnNP5zTd7yyr2SC1j299sBCnWjss') // private to recipient
var scan = bitcoin.ECPair.fromWIF('L5DkCk3xLLoGKncqKsWQTdaPSR4V8gzc14WVghysQGkdryRudjBM') // private to scanner/recipient
var nonce = bitcoin.ECPair.fromWIF('KxVqB96pxbw1pokzQrZkQbLfVBjjHFfp2mFfEp8wuEyGenLFJhM9') // private to sender
// ... recipient reveals public key(s) (recipient.Q, scan.Q) to sender
var forSender = stealthDualSend(nonce.d, recipient.Q, scan.Q)
assert.throws(function () { forSender.toWIF() }, /Error: Missing private key/)
// ... sender reveals nonce public key (nonce.Q) to scanner
var forScanner = stealthDualScan(scan.d, recipient.Q, nonce.Q)
assert.throws(function () { forScanner.toWIF() }, /Error: Missing private key/)
// ... scanner reveals relevant transaction + nonce public key (nonce.Q) to recipient
var forRecipient = stealthDualReceive(scan.d, recipient.d, nonce.Q)
assert.doesNotThrow(function () { forRecipient.toWIF() })
// scanner, sender and recipient, all derived same address
assert.equal(forSender.getAddress(), forScanner.getAddress())
assert.equal(forSender.getAddress(), forRecipient.getAddress())
})
})