diff --git a/src/ecdsa.js b/src/ecdsa.js index 56f35f4..71f0bbd 100644 --- a/src/ecdsa.js +++ b/src/ecdsa.js @@ -115,21 +115,27 @@ function verifyRaw (curve, e, signature, Q) { if (r.signum() <= 0 || r.compareTo(n) >= 0) return false if (s.signum() <= 0 || s.compareTo(n) >= 0) return false - // c = s^-1 mod n - var c = s.modInverse(n) + // Compute s^-1 + var sInv = s.modInverse(n) // 1.4.4 Compute u1 = es^−1 mod n // u2 = rs^−1 mod n - var u1 = e.multiply(c).mod(n) - var u2 = r.multiply(c).mod(n) + var u1 = e.multiply(sInv).mod(n) + var u2 = r.multiply(sInv).mod(n) - // 1.4.5 Compute R = (xR, yR) = u1G + u2Q + // 1.4.5 Compute R = (xR, yR) + // R = u1G + u2Q var R = G.multiplyTwo(u1, Q, u2) - var v = R.affineX.mod(n) // 1.4.5 (cont.) Enforce R is not at infinity if (curve.isInfinity(R)) return false + // 1.4.6 Convert the field element R.x to an integer + var xR = R.affineX + + // 1.4.7 Set v = xR mod n + var v = xR.mod(n) + // 1.4.8 If v = r, output "valid", and if v != r, output "invalid" return v.equals(r) }