commit
c6bc0ebdcb
7 changed files with 278 additions and 310 deletions
513
src/ecdsa.js
513
src/ecdsa.js
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@ -1,317 +1,272 @@
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var assert = require('assert')
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var assert = require('assert')
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var crypto = require('./crypto')
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var crypto = require('./crypto')
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var sec = require('./sec')
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var ecparams = sec("secp256k1")
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var BigInteger = require('bigi')
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var BigInteger = require('bigi')
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var ECPointFp = require('./ec').ECPointFp
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var ECPointFp = require('./ec').ECPointFp
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function implShamirsTrick(P, k, Q, l) {
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function deterministicGenerateK(ecparams, hash, D) {
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var m = Math.max(k.bitLength(), l.bitLength())
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assert(Buffer.isBuffer(hash), 'Hash must be a Buffer, not ' + hash)
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var Z = P.add2D(Q)
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assert.equal(hash.length, 32, 'Hash must be 256 bit')
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var R = P.curve.getInfinity()
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assert(D instanceof BigInteger, 'Private key must be a BigInteger')
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for (var i = m - 1; i >= 0; --i) {
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var x = D.toBuffer(32)
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R = R.twice2D()
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var k = new Buffer(32)
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var v = new Buffer(32)
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k.fill(0)
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v.fill(1)
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R.z = BigInteger.ONE
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k = crypto.HmacSHA256(Buffer.concat([v, new Buffer([0]), x, hash]), k)
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v = crypto.HmacSHA256(v, k)
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if (k.testBit(i)) {
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k = crypto.HmacSHA256(Buffer.concat([v, new Buffer([1]), x, hash]), k)
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if (l.testBit(i)) {
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v = crypto.HmacSHA256(v, k)
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R = R.add2D(Z)
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v = crypto.HmacSHA256(v, k)
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} else {
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R = R.add2D(P)
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}
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} else {
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if (l.testBit(i)) {
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R = R.add2D(Q)
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}
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}
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}
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return R
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var n = ecparams.getN()
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var kB = BigInteger.fromBuffer(v).mod(n)
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assert(kB.compareTo(BigInteger.ONE) > 0, 'Invalid k value')
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assert(kB.compareTo(ecparams.getN()) < 0, 'Invalid k value')
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return kB
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}
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}
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var ecdsa = {
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function sign(ecparams, hash, D) {
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deterministicGenerateK: function(hash, D) {
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var k = deterministicGenerateK(ecparams, hash, D)
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assert(Buffer.isBuffer(hash), 'Hash must be a Buffer')
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assert.equal(hash.length, 32, 'Hash must be 256 bit')
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assert(D instanceof BigInteger, 'Private key must be a BigInteger')
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var x = D.toBuffer(32)
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var n = ecparams.getN()
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var k = new Buffer(32)
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var G = ecparams.getG()
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var v = new Buffer(32)
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var Q = G.multiply(k)
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k.fill(0)
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var e = BigInteger.fromBuffer(hash)
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v.fill(1)
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k = crypto.HmacSHA256(Buffer.concat([v, new Buffer([0]), x, hash]), k)
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var r = Q.getX().toBigInteger().mod(n)
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v = crypto.HmacSHA256(v, k)
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assert.notEqual(r.signum(), 0, 'Invalid R value')
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k = crypto.HmacSHA256(Buffer.concat([v, new Buffer([1]), x, hash]), k)
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var s = k.modInverse(n).multiply(e.add(D.multiply(r))).mod(n)
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v = crypto.HmacSHA256(v, k)
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assert.notEqual(s.signum(), 0, 'Invalid S value')
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v = crypto.HmacSHA256(v, k)
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var n = ecparams.getN()
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var N_OVER_TWO = n.shiftRight(1)
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var kB = BigInteger.fromBuffer(v).mod(n)
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assert(kB.compareTo(BigInteger.ONE) > 0, 'Invalid k value')
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assert(kB.compareTo(ecparams.getN()) < 0, 'Invalid k value')
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return kB
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// enforce low S values, see bip62: 'low s values in signatures'
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},
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if (s.compareTo(N_OVER_TWO) > 0) {
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s = n.subtract(s)
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}
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sign: function (hash, D) {
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return {r: r, s: s}
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var k = ecdsa.deterministicGenerateK(hash, D)
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}
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var n = ecparams.getN()
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function verify(ecparams, hash, r, s, Q) {
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var G = ecparams.getG()
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var e = BigInteger.fromBuffer(hash)
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var Q = G.multiply(k)
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var e = BigInteger.fromBuffer(hash)
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var r = Q.getX().toBigInteger().mod(n)
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return verifyRaw(ecparams, e, r, s, Q)
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assert.notEqual(r.signum(), 0, 'Invalid R value')
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}
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var s = k.modInverse(n).multiply(e.add(D.multiply(r))).mod(n)
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function verifyRaw(ecparams, e, r, s, Q) {
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assert.notEqual(s.signum(), 0, 'Invalid S value')
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var n = ecparams.getN()
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var G = ecparams.getG()
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var N_OVER_TWO = n.shiftRight(1)
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if (r.compareTo(BigInteger.ONE) < 0 || r.compareTo(n) >= 0) {
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return false
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}
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// enforce low S values, see bip62: 'low s values in signatures'
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if (s.compareTo(BigInteger.ONE) < 0 || s.compareTo(n) >= 0) {
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if (s.compareTo(N_OVER_TWO) > 0) {
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return false
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s = n.subtract(s)
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}
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}
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return ecdsa.serializeSig(r, s)
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var c = s.modInverse(n)
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},
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var u1 = e.multiply(c).mod(n)
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var u2 = r.multiply(c).mod(n)
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verify: function (hash, sig, pubkey) {
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var point = G.multiplyTwo(u1, Q, u2)
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var r,s
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var v = point.getX().toBigInteger().mod(n)
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if (Array.isArray(sig) || Buffer.isBuffer(sig)) {
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var obj = ecdsa.parseSig(sig)
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r = obj.r
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s = obj.s
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} else if ("object" === typeof sig && sig.r && sig.s) {
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r = sig.r
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s = sig.s
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} else {
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throw new Error("Invalid value for signature")
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}
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var Q
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return v.equals(r)
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if (pubkey instanceof ECPointFp) {
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}
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Q = pubkey
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} else if (Array.isArray(pubkey) || Buffer.isBuffer(pubkey)) {
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Q = ECPointFp.decodeFrom(ecparams.getCurve(), pubkey)
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} else {
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throw new Error("Invalid format for pubkey value, must be byte array or ECPointFp")
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}
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var e = BigInteger.fromBuffer(hash)
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return ecdsa.verifyRaw(e, r, s, Q)
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/**
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},
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* Serialize a signature into DER format.
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*
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* Takes two BigIntegers representing r and s and returns a byte array.
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*/
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function serializeSig(r, s) {
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var rBa = r.toByteArraySigned()
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var sBa = s.toByteArraySigned()
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verifyRaw: function (e, r, s, Q) {
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var sequence = []
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var n = ecparams.getN()
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sequence.push(0x02); // INTEGER
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var G = ecparams.getG()
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sequence.push(rBa.length)
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sequence = sequence.concat(rBa)
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if (r.compareTo(BigInteger.ONE) < 0 || r.compareTo(n) >= 0) {
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sequence.push(0x02); // INTEGER
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return false
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sequence.push(sBa.length)
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}
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sequence = sequence.concat(sBa)
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if (s.compareTo(BigInteger.ONE) < 0 || s.compareTo(n) >= 0) {
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sequence.unshift(sequence.length)
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return false
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sequence.unshift(0x30); // SEQUENCE
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}
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var c = s.modInverse(n)
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return sequence
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var u1 = e.multiply(c).mod(n)
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}
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var u2 = r.multiply(c).mod(n)
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// TODO(!!!): For some reason Shamir's trick isn't working with
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/**
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// signed message verification!? Probably an implementation
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* Parses a buffer containing a DER-encoded signature.
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// error!
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*
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//var point = implShamirsTrick(G, u1, Q, u2)
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* This function will return an object of the form:
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var point = G.multiply(u1).add(Q.multiply(u2))
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*
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* {
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* r: BigInteger,
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* s: BigInteger
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* }
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*/
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function parseSig(buffer) {
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assert.equal(buffer.readUInt8(0), 0x30, 'Not a DER sequence')
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assert.equal(buffer.readUInt8(1), buffer.length - 2, 'Invalid sequence length')
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var v = point.getX().toBigInteger().mod(n)
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assert.equal(buffer.readUInt8(2), 0x02, 'Expected DER integer')
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var rLen = buffer.readUInt8(3)
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var rB = buffer.slice(4, 4 + rLen)
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return v.equals(r)
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var offset = 4 + rLen
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},
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assert.equal(buffer.readUInt8(offset), 0x02, 'Expected a 2nd DER integer')
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var sLen = buffer.readUInt8(1 + offset)
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var sB = buffer.slice(2 + offset)
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/**
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return {
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* Serialize a signature into DER format.
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r: BigInteger.fromByteArraySigned(rB),
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*
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s: BigInteger.fromByteArraySigned(sB)
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* Takes two BigIntegers representing r and s and returns a byte array.
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*/
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serializeSig: function (r, s) {
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var rBa = r.toByteArraySigned()
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var sBa = s.toByteArraySigned()
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var sequence = []
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sequence.push(0x02); // INTEGER
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sequence.push(rBa.length)
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sequence = sequence.concat(rBa)
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sequence.push(0x02); // INTEGER
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sequence.push(sBa.length)
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sequence = sequence.concat(sBa)
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sequence.unshift(sequence.length)
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sequence.unshift(0x30); // SEQUENCE
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return sequence
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},
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/**
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* Parses a buffer containing a DER-encoded signature.
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*
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* This function will return an object of the form:
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*
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* {
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* r: BigInteger,
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* s: BigInteger
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* }
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*/
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parseSig: function (buffer) {
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if (Array.isArray(buffer)) buffer = new Buffer(buffer) // FIXME: transitionary
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assert.equal(buffer.readUInt8(0), 0x30, 'Not a DER sequence')
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assert.equal(buffer.readUInt8(1), buffer.length - 2, 'Invalid sequence length')
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assert.equal(buffer.readUInt8(2), 0x02, 'Expected DER integer')
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var rLen = buffer.readUInt8(3)
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var rB = buffer.slice(4, 4 + rLen)
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var offset = 4 + rLen
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assert.equal(buffer.readUInt8(offset), 0x02, 'Expected a 2nd DER integer')
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var sLen = buffer.readUInt8(1 + offset)
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var sB = buffer.slice(2 + offset)
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return {
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r: BigInteger.fromByteArraySigned(rB),
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s: BigInteger.fromByteArraySigned(sB)
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}
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},
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serializeSigCompact: function(r, s, i, compressed) {
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if (compressed) {
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i += 4
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}
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i += 27
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var buffer = new Buffer(65)
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buffer.writeUInt8(i, 0)
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r.toBuffer(32).copy(buffer, 1)
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s.toBuffer(32).copy(buffer, 33)
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return buffer
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},
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parseSigCompact: function (buffer) {
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assert.equal(buffer.length, 65, 'Invalid signature length')
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var i = buffer.readUInt8(0) - 27
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// At most 3 bits
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assert.equal(i, i & 7, 'Invalid signature type')
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var compressed = !!(i & 4)
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// Recovery param only
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i = i & 3
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var r = BigInteger.fromBuffer(buffer.slice(1, 33))
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var s = BigInteger.fromBuffer(buffer.slice(33))
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return {
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r: r,
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s: s,
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i: i,
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compressed: compressed
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}
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},
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/**
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* Recover a public key from a signature.
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*
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* See SEC 1: Elliptic Curve Cryptography, section 4.1.6, "Public
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* Key Recovery Operation".
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*
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* http://www.secg.org/download/aid-780/sec1-v2.pdf
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*/
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recoverPubKey: function (r, s, hash, i) {
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assert.strictEqual(i & 3, i, 'The recovery param is more than two bits')
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// A set LSB signifies that the y-coordinate is odd
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// By reduction, the y-coordinate is even if it is clear
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var isYEven = !(i & 1)
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// The more significant bit specifies whether we should use the
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// first or second candidate key.
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var isSecondKey = i >> 1
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var n = ecparams.getN()
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var G = ecparams.getG()
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var curve = ecparams.getCurve()
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var p = curve.getQ()
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var a = curve.getA().toBigInteger()
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var b = curve.getB().toBigInteger()
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// We precalculate (p + 1) / 4 where p is the field order
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if (!curve.P_OVER_FOUR) {
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curve.P_OVER_FOUR = p.add(BigInteger.ONE).shiftRight(2)
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}
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// 1.1 Compute x
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var x = isSecondKey ? r.add(n) : r
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// 1.3 Convert x to point
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var alpha = x.pow(3).add(a.multiply(x)).add(b).mod(p)
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var beta = alpha.modPow(curve.P_OVER_FOUR, p)
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// If beta is even, but y isn't, or vice versa, then convert it,
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// otherwise we're done and y == beta.
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var y = (beta.isEven() ^ isYEven) ? p.subtract(beta) : beta
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// 1.4 Check that nR isn't at infinity
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var R = new ECPointFp(curve, curve.fromBigInteger(x), curve.fromBigInteger(y))
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R.validate()
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// 1.5 Compute e from M
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var e = BigInteger.fromBuffer(hash)
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var eNeg = BigInteger.ZERO.subtract(e).mod(n)
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// 1.6 Compute Q = r^-1 (sR - eG)
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var rInv = r.modInverse(n)
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var Q = implShamirsTrick(R, s, G, eNeg).multiply(rInv)
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Q.validate()
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if (!ecdsa.verifyRaw(e, r, s, Q)) {
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throw new Error("Pubkey recovery unsuccessful")
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}
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return Q
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},
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/**
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* Calculate pubkey extraction parameter.
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*
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* When extracting a pubkey from a signature, we have to
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* distinguish four different cases. Rather than putting this
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* burden on the verifier, Bitcoin includes a 2-bit value with the
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* signature.
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*
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* This function simply tries all four cases and returns the value
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* that resulted in a successful pubkey recovery.
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*/
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calcPubKeyRecoveryParam: function (origPubKey, r, s, hash) {
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for (var i = 0; i < 4; i++) {
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var pubKey = ecdsa.recoverPubKey(r, s, hash, i)
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if (pubKey.equals(origPubKey)) {
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return i
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}
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}
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throw new Error("Unable to find valid recovery factor")
|
|
||||||
}
|
}
|
||||||
}
|
}
|
||||||
|
|
||||||
module.exports = ecdsa
|
function serializeSigCompact(r, s, i, compressed) {
|
||||||
|
if (compressed) {
|
||||||
|
i += 4
|
||||||
|
}
|
||||||
|
|
||||||
|
i += 27
|
||||||
|
|
||||||
|
var buffer = new Buffer(65)
|
||||||
|
buffer.writeUInt8(i, 0)
|
||||||
|
r.toBuffer(32).copy(buffer, 1)
|
||||||
|
s.toBuffer(32).copy(buffer, 33)
|
||||||
|
|
||||||
|
return buffer
|
||||||
|
}
|
||||||
|
|
||||||
|
function parseSigCompact(buffer) {
|
||||||
|
assert.equal(buffer.length, 65, 'Invalid signature length')
|
||||||
|
var i = buffer.readUInt8(0) - 27
|
||||||
|
|
||||||
|
// At most 3 bits
|
||||||
|
assert.equal(i, i & 7, 'Invalid signature type')
|
||||||
|
var compressed = !!(i & 4)
|
||||||
|
|
||||||
|
// Recovery param only
|
||||||
|
i = i & 3
|
||||||
|
|
||||||
|
var r = BigInteger.fromBuffer(buffer.slice(1, 33))
|
||||||
|
var s = BigInteger.fromBuffer(buffer.slice(33))
|
||||||
|
|
||||||
|
return {
|
||||||
|
r: r,
|
||||||
|
s: s,
|
||||||
|
i: i,
|
||||||
|
compressed: compressed
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
/**
|
||||||
|
* Recover a public key from a signature.
|
||||||
|
*
|
||||||
|
* See SEC 1: Elliptic Curve Cryptography, section 4.1.6, "Public
|
||||||
|
* Key Recovery Operation".
|
||||||
|
*
|
||||||
|
* http://www.secg.org/download/aid-780/sec1-v2.pdf
|
||||||
|
*/
|
||||||
|
function recoverPubKey(ecparams, e, r, s, i) {
|
||||||
|
assert.strictEqual(i & 3, i, 'The recovery param is more than two bits')
|
||||||
|
|
||||||
|
// A set LSB signifies that the y-coordinate is odd
|
||||||
|
// By reduction, the y-coordinate is even if it is clear
|
||||||
|
var isYEven = !(i & 1)
|
||||||
|
|
||||||
|
// The more significant bit specifies whether we should use the
|
||||||
|
// first or second candidate key.
|
||||||
|
var isSecondKey = i >> 1
|
||||||
|
|
||||||
|
var n = ecparams.getN()
|
||||||
|
var G = ecparams.getG()
|
||||||
|
var curve = ecparams.getCurve()
|
||||||
|
var p = curve.getQ()
|
||||||
|
var a = curve.getA().toBigInteger()
|
||||||
|
var b = curve.getB().toBigInteger()
|
||||||
|
|
||||||
|
// We precalculate (p + 1) / 4 where p is the field order
|
||||||
|
if (!curve.P_OVER_FOUR) {
|
||||||
|
curve.P_OVER_FOUR = p.add(BigInteger.ONE).shiftRight(2)
|
||||||
|
}
|
||||||
|
|
||||||
|
// 1.1 Compute x
|
||||||
|
var x = isSecondKey ? r.add(n) : r
|
||||||
|
|
||||||
|
// 1.3 Convert x to point
|
||||||
|
var alpha = x.pow(3).add(a.multiply(x)).add(b).mod(p)
|
||||||
|
var beta = alpha.modPow(curve.P_OVER_FOUR, p)
|
||||||
|
|
||||||
|
// If beta is even, but y isn't, or vice versa, then convert it,
|
||||||
|
// otherwise we're done and y == beta.
|
||||||
|
var y = (beta.isEven() ^ isYEven) ? p.subtract(beta) : beta
|
||||||
|
|
||||||
|
// 1.4 Check that nR isn't at infinity
|
||||||
|
var R = new ECPointFp(curve, curve.fromBigInteger(x), curve.fromBigInteger(y))
|
||||||
|
R.validate()
|
||||||
|
|
||||||
|
// 1.5 Compute -e from e
|
||||||
|
var eNeg = e.negate().mod(n)
|
||||||
|
|
||||||
|
// 1.6 Compute Q = r^-1 (sR - eG)
|
||||||
|
// Q = r^-1 (sR + -eG)
|
||||||
|
var rInv = r.modInverse(n)
|
||||||
|
|
||||||
|
var Q = R.multiplyTwo(s, G, eNeg).multiply(rInv)
|
||||||
|
Q.validate()
|
||||||
|
|
||||||
|
if (!verifyRaw(ecparams, e, r, s, Q)) {
|
||||||
|
throw new Error("Pubkey recovery unsuccessful")
|
||||||
|
}
|
||||||
|
|
||||||
|
return Q
|
||||||
|
}
|
||||||
|
|
||||||
|
/**
|
||||||
|
* Calculate pubkey extraction parameter.
|
||||||
|
*
|
||||||
|
* When extracting a pubkey from a signature, we have to
|
||||||
|
* distinguish four different cases. Rather than putting this
|
||||||
|
* burden on the verifier, Bitcoin includes a 2-bit value with the
|
||||||
|
* signature.
|
||||||
|
*
|
||||||
|
* This function simply tries all four cases and returns the value
|
||||||
|
* that resulted in a successful pubkey recovery.
|
||||||
|
*/
|
||||||
|
function calcPubKeyRecoveryParam(ecparams, e, r, s, Q) {
|
||||||
|
for (var i = 0; i < 4; i++) {
|
||||||
|
var Qprime = recoverPubKey(ecparams, e, r, s, i)
|
||||||
|
|
||||||
|
if (Qprime.equals(Q)) {
|
||||||
|
return i
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
throw new Error('Unable to find valid recovery factor')
|
||||||
|
}
|
||||||
|
|
||||||
|
module.exports = {
|
||||||
|
calcPubKeyRecoveryParam: calcPubKeyRecoveryParam,
|
||||||
|
deterministicGenerateK: deterministicGenerateK,
|
||||||
|
recoverPubKey: recoverPubKey,
|
||||||
|
sign: sign,
|
||||||
|
verify: verify,
|
||||||
|
verifyRaw: verifyRaw,
|
||||||
|
serializeSig: serializeSig,
|
||||||
|
parseSig: parseSig,
|
||||||
|
serializeSigCompact: serializeSigCompact,
|
||||||
|
parseSigCompact: parseSigCompact
|
||||||
|
}
|
||||||
|
|
|
@ -63,7 +63,7 @@ ECKey.prototype.toWIF = function(version) {
|
||||||
|
|
||||||
// Operations
|
// Operations
|
||||||
ECKey.prototype.sign = function(hash) {
|
ECKey.prototype.sign = function(hash) {
|
||||||
return ecdsa.sign(hash, this.D)
|
return ecdsa.sign(ecparams, hash, this.D)
|
||||||
}
|
}
|
||||||
|
|
||||||
module.exports = ECKey
|
module.exports = ECKey
|
||||||
|
|
|
@ -36,8 +36,8 @@ ECPubKey.prototype.getAddress = function(version) {
|
||||||
return new Address(crypto.hash160(this.toBuffer()), version)
|
return new Address(crypto.hash160(this.toBuffer()), version)
|
||||||
}
|
}
|
||||||
|
|
||||||
ECPubKey.prototype.verify = function(hash, sig) {
|
ECPubKey.prototype.verify = function(hash, signature) {
|
||||||
return ecdsa.verify(hash, sig, this.Q)
|
return ecdsa.verify(ecparams, hash, signature.r, signature.s, this.Q)
|
||||||
}
|
}
|
||||||
|
|
||||||
// Export functions
|
// Export functions
|
||||||
|
|
|
@ -1,5 +1,6 @@
|
||||||
/// Implements Bitcoin's feature for signing arbitrary messages.
|
/// Implements Bitcoin's feature for signing arbitrary messages.
|
||||||
var Address = require('./address')
|
var Address = require('./address')
|
||||||
|
var BigInteger = require('bigi')
|
||||||
var bufferutils = require('./bufferutils')
|
var bufferutils = require('./bufferutils')
|
||||||
var crypto = require('./crypto')
|
var crypto = require('./crypto')
|
||||||
var ecdsa = require('./ecdsa')
|
var ecdsa = require('./ecdsa')
|
||||||
|
@ -8,6 +9,9 @@ var networks = require('./networks')
|
||||||
var Address = require('./address')
|
var Address = require('./address')
|
||||||
var ECPubKey = require('./ecpubkey')
|
var ECPubKey = require('./ecpubkey')
|
||||||
|
|
||||||
|
var sec = require('./sec')
|
||||||
|
var ecparams = sec('secp256k1')
|
||||||
|
|
||||||
function magicHash(message, network) {
|
function magicHash(message, network) {
|
||||||
var magicPrefix = new Buffer(network.magicPrefix)
|
var magicPrefix = new Buffer(network.magicPrefix)
|
||||||
var messageBuffer = new Buffer(message)
|
var messageBuffer = new Buffer(message)
|
||||||
|
@ -24,8 +28,9 @@ function sign(key, message, network) {
|
||||||
network = network || networks.bitcoin
|
network = network || networks.bitcoin
|
||||||
|
|
||||||
var hash = magicHash(message, network)
|
var hash = magicHash(message, network)
|
||||||
var sig = ecdsa.parseSig(key.sign(hash))
|
var sig = key.sign(hash)
|
||||||
var i = ecdsa.calcPubKeyRecoveryParam(key.pub.Q, sig.r, sig.s, hash)
|
var e = BigInteger.fromBuffer(hash)
|
||||||
|
var i = ecdsa.calcPubKeyRecoveryParam(ecparams, e, sig.r, sig.s, key.pub.Q)
|
||||||
|
|
||||||
return ecdsa.serializeSigCompact(sig.r, sig.s, i, key.pub.compressed)
|
return ecdsa.serializeSigCompact(sig.r, sig.s, i, key.pub.compressed)
|
||||||
}
|
}
|
||||||
|
@ -40,7 +45,8 @@ function verify(address, compactSig, message, network) {
|
||||||
|
|
||||||
var hash = magicHash(message, network)
|
var hash = magicHash(message, network)
|
||||||
var sig = ecdsa.parseSigCompact(compactSig)
|
var sig = ecdsa.parseSigCompact(compactSig)
|
||||||
var Q = ecdsa.recoverPubKey(sig.r, sig.s, hash, sig.i)
|
var e = BigInteger.fromBuffer(hash)
|
||||||
|
var Q = ecdsa.recoverPubKey(ecparams, e, sig.r, sig.s, sig.i)
|
||||||
|
|
||||||
var pubKey = new ECPubKey(Q, sig.compressed)
|
var pubKey = new ECPubKey(Q, sig.compressed)
|
||||||
return pubKey.getAddress(address.version).toString() === address.toString()
|
return pubKey.getAddress(address.version).toString() === address.toString()
|
||||||
|
|
|
@ -364,27 +364,35 @@ Transaction.prototype.sign = function(index, key, type) {
|
||||||
this.setScriptSig(index, scriptSig)
|
this.setScriptSig(index, scriptSig)
|
||||||
}
|
}
|
||||||
|
|
||||||
Transaction.prototype.signScriptSig = function(index, script, key, type) {
|
Transaction.prototype.signScriptSig = function(index, scriptPubKey, key, type) {
|
||||||
type = type || SIGHASH_ALL
|
type = type || SIGHASH_ALL
|
||||||
|
|
||||||
assert((index >= 0), 'Invalid vin index')
|
assert((index >= 0), 'Invalid vin index')
|
||||||
assert(script instanceof Script, 'Invalid Script object')
|
assert(scriptPubKey instanceof Script, 'Invalid Script object')
|
||||||
assert(key instanceof ECKey, 'Invalid private key')
|
assert(key instanceof ECKey, 'Invalid private key')
|
||||||
// assert.equal(type & 0x7F, type, 'Invalid type') // TODO
|
// assert.equal(type & 0x7F, type, 'Invalid type') // TODO
|
||||||
|
|
||||||
var hash = this.hashForSignature(script, index, type)
|
var hash = this.hashForSignature(scriptPubKey, index, type)
|
||||||
return key.sign(hash).concat([type])
|
var sig = key.sign(hash)
|
||||||
|
var DERsig = ecdsa.serializeSig(sig.r, sig.s)
|
||||||
|
|
||||||
|
return Buffer.concat([
|
||||||
|
new Buffer(DERsig),
|
||||||
|
new Buffer([type])
|
||||||
|
])
|
||||||
}
|
}
|
||||||
|
|
||||||
Transaction.prototype.setScriptSig = function(index, script) {
|
Transaction.prototype.setScriptSig = function(index, script) {
|
||||||
this.ins[index].script = script
|
this.ins[index].script = script
|
||||||
}
|
}
|
||||||
|
|
||||||
Transaction.prototype.validateSig = function(index, script, pub, sig) {
|
Transaction.prototype.validateSig = function(index, script, pub, DERsig) {
|
||||||
var type = sig[sig.length - 1]
|
var type = DERsig.readUInt8(DERsig.length - 1)
|
||||||
var hash = this.hashForSignature(script, index, type)
|
DERsig = DERsig.slice(0, -1)
|
||||||
|
|
||||||
|
var hash = this.hashForSignature(script, index, type)
|
||||||
|
var sig = ecdsa.parseSig(DERsig)
|
||||||
|
|
||||||
sig = sig.slice(0, -1)
|
|
||||||
return pub.verify(hash, sig)
|
return pub.verify(hash, sig)
|
||||||
}
|
}
|
||||||
|
|
||||||
|
|
|
@ -17,10 +17,10 @@ describe('ecdsa', function() {
|
||||||
describe('deterministicGenerateK', function() {
|
describe('deterministicGenerateK', function() {
|
||||||
it('matches the test vectors', function() {
|
it('matches the test vectors', function() {
|
||||||
fixtures.valid.forEach(function(f) {
|
fixtures.valid.forEach(function(f) {
|
||||||
var priv = BigInteger.fromHex(f.D)
|
var D = BigInteger.fromHex(f.D)
|
||||||
var h1 = crypto.sha256(f.message)
|
var h1 = crypto.sha256(f.message)
|
||||||
|
|
||||||
var k = ecdsa.deterministicGenerateK(h1, priv)
|
var k = ecdsa.deterministicGenerateK(ecparams, h1, D)
|
||||||
assert.equal(k.toHex(), f.k)
|
assert.equal(k.toHex(), f.k)
|
||||||
})
|
})
|
||||||
})
|
})
|
||||||
|
@ -28,14 +28,16 @@ describe('ecdsa', function() {
|
||||||
|
|
||||||
describe('recoverPubKey', function() {
|
describe('recoverPubKey', function() {
|
||||||
it('succesfully recovers a public key', function() {
|
it('succesfully recovers a public key', function() {
|
||||||
var signature = new Buffer('H0PG6+PUo96UPTJ/DVj8aBU5it+Nuli4YdsLuTMvfJxoHH9Jb7jYTQXCCOX2jrTChD5S1ic3vCrUQHdmB5/sEQY=', 'base64')
|
var D = BigInteger.ONE
|
||||||
|
var signature = new Buffer('INcvXVVEFyIfHLbDX+xoxlKFn3Wzj9g0UbhObXdMq+YMKC252o5RHFr0/cKdQe1WsBLUBi4morhgZ77obDJVuV0=', 'base64')
|
||||||
|
|
||||||
var obj = ecdsa.parseSigCompact(signature)
|
var Q = ecparams.getG().multiply(D)
|
||||||
var hash = message.magicHash('1111', networks.bitcoin)
|
var hash = message.magicHash('1111', networks.bitcoin)
|
||||||
|
var e = BigInteger.fromBuffer(hash)
|
||||||
|
var psig = ecdsa.parseSigCompact(signature)
|
||||||
|
|
||||||
var pubKey = new ECPubKey(ecdsa.recoverPubKey(obj.r, obj.s, hash, obj.i))
|
var Qprime = ecdsa.recoverPubKey(ecparams, e, psig.r, psig.s, psig.i)
|
||||||
|
assert(Q.equals(Qprime))
|
||||||
assert.equal(pubKey.toHex(), '02e8fcf4d749b35879bc1f3b14b49e67ab7301da3558c5a9b74a54f1e6339c334c')
|
|
||||||
})
|
})
|
||||||
})
|
})
|
||||||
|
|
||||||
|
@ -43,9 +45,8 @@ describe('ecdsa', function() {
|
||||||
it('matches the test vectors', function() {
|
it('matches the test vectors', function() {
|
||||||
fixtures.valid.forEach(function(f) {
|
fixtures.valid.forEach(function(f) {
|
||||||
var D = BigInteger.fromHex(f.D)
|
var D = BigInteger.fromHex(f.D)
|
||||||
var priv = new ECKey(D)
|
|
||||||
var hash = crypto.sha256(f.message)
|
var hash = crypto.sha256(f.message)
|
||||||
var sig = ecdsa.parseSig(priv.sign(hash))
|
var sig = ecdsa.sign(ecparams, hash, D)
|
||||||
|
|
||||||
assert.equal(sig.r.toString(), f.signature.r)
|
assert.equal(sig.r.toString(), f.signature.r)
|
||||||
assert.equal(sig.s.toString(), f.signature.s)
|
assert.equal(sig.s.toString(), f.signature.s)
|
||||||
|
@ -53,14 +54,12 @@ describe('ecdsa', function() {
|
||||||
})
|
})
|
||||||
|
|
||||||
it('should sign with low S value', function() {
|
it('should sign with low S value', function() {
|
||||||
var priv = ECKey.makeRandom()
|
|
||||||
var hash = crypto.sha256('Vires in numeris')
|
var hash = crypto.sha256('Vires in numeris')
|
||||||
var signature = priv.sign(hash)
|
var sig = ecdsa.sign(ecparams, hash, BigInteger.ONE)
|
||||||
var psig = ecdsa.parseSig(signature)
|
|
||||||
|
|
||||||
// See BIP62 for more information
|
// See BIP62 for more information
|
||||||
var N_OVER_TWO = ecparams.getN().shiftRight(1)
|
var N_OVER_TWO = ecparams.getN().shiftRight(1)
|
||||||
assert(psig.s.compareTo(N_OVER_TWO) <= 0)
|
assert(sig.s.compareTo(N_OVER_TWO) <= 0)
|
||||||
})
|
})
|
||||||
})
|
})
|
||||||
|
|
||||||
|
@ -68,13 +67,13 @@ describe('ecdsa', function() {
|
||||||
it('matches the test vectors', function() {
|
it('matches the test vectors', function() {
|
||||||
fixtures.valid.forEach(function(f) {
|
fixtures.valid.forEach(function(f) {
|
||||||
var D = BigInteger.fromHex(f.D)
|
var D = BigInteger.fromHex(f.D)
|
||||||
var priv = new ECKey(D)
|
var Q = ecparams.getG().multiply(D)
|
||||||
|
|
||||||
var r = new BigInteger(f.signature.r)
|
var r = new BigInteger(f.signature.r)
|
||||||
var s = new BigInteger(f.signature.s)
|
var s = new BigInteger(f.signature.s)
|
||||||
var e = BigInteger.fromBuffer(crypto.sha256(f.message))
|
var e = BigInteger.fromBuffer(crypto.sha256(f.message))
|
||||||
|
|
||||||
assert(ecdsa.verifyRaw(e, r, s, priv.pub.Q))
|
assert(ecdsa.verifyRaw(ecparams, e, r, s, Q))
|
||||||
})
|
})
|
||||||
})
|
})
|
||||||
})
|
})
|
||||||
|
|
|
@ -197,7 +197,7 @@ describe('Transaction', function() {
|
||||||
tx.sign(0, key)
|
tx.sign(0, key)
|
||||||
|
|
||||||
var script = prevTx.outs[0].script
|
var script = prevTx.outs[0].script
|
||||||
var sig = tx.ins[0].script.chunks[0]
|
var sig = new Buffer(tx.ins[0].script.chunks[0])
|
||||||
|
|
||||||
assert.equal(tx.validateSig(0, script, key.pub, sig), true)
|
assert.equal(tx.validateSig(0, script, key.pub, sig), true)
|
||||||
})
|
})
|
||||||
|
@ -213,7 +213,7 @@ describe('Transaction', function() {
|
||||||
it('returns true for valid signature', function(){
|
it('returns true for valid signature', function(){
|
||||||
var key = ECKey.fromWIF('L44f7zxJ5Zw4EK9HZtyAnzCYz2vcZ5wiJf9AuwhJakiV4xVkxBeb')
|
var key = ECKey.fromWIF('L44f7zxJ5Zw4EK9HZtyAnzCYz2vcZ5wiJf9AuwhJakiV4xVkxBeb')
|
||||||
var script = prevTx.outs[0].script
|
var script = prevTx.outs[0].script
|
||||||
var sig = validTx.ins[0].script.chunks[0]
|
var sig = new Buffer(validTx.ins[0].script.chunks[0])
|
||||||
|
|
||||||
assert.equal(validTx.validateSig(0, script, key.pub, sig), true)
|
assert.equal(validTx.validateSig(0, script, key.pub, sig), true)
|
||||||
})
|
})
|
||||||
|
|
Loading…
Reference in a new issue