ecdsa: remove unused functions

10 years ago · 7cdabef954
3 changed files with 0 additions and 206 deletions
--- a/src/ecdsa.js
+++ b/src/ecdsa.js
@ -154,93 +154,8 @@ function verify (hash, signature, Q) {
  return v.equals(r)
 }
 /**
  * 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 (e, signature, i) {
  typeforce(types.tuple(
    types.BigInt,
    types.ECSignature,
    types.UInt2
  ), arguments)
  var n = secp256k1.n
  var G = secp256k1.G
  var r = signature.r
  var s = signature.s
  if (r.signum() <= 0 || r.compareTo(n) >= 0) throw new Error('Invalid r value')
  if (s.signum() <= 0 || s.compareTo(n) >= 0) throw new Error('Invalid s value')
  // A set LSB signifies that the y-coordinate is odd
  var isYOdd = i & 1
  // The more significant bit specifies whether we should use the
  // first or second candidate key.
  var isSecondKey = i >> 1
  // 1.1 Let x = r + jn
  var x = isSecondKey ? r.add(n) : r
  var R = secp256k1.pointFromX(isYOdd, x)
  // 1.4 Check that nR is at infinity
  var nR = R.multiply(n)
  if (!secp256k1.isInfinity(nR)) throw new Error('nR is not a valid curve point')
  // Compute r^-1
  var rInv = r.modInverse(n)
  // Compute -e from e
  var eNeg = e.negate().mod(n)
  // 1.6.1 Compute Q = r^-1 (sR -  eG)
  //               Q = r^-1 (sR + -eG)
  var Q = R.multiplyTwo(s, G, eNeg).multiply(rInv)
  secp256k1.validate(Q)
  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 (e, signature, Q) {
  typeforce(types.tuple(
    types.BigInt,
    types.ECSignature,
    types.ECPoint
  ), arguments)
  for (var i = 0; i < 4; i++) {
    var Qprime = recoverPubKey(e, signature, i)
    // 1.6.2 Verify Q
    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,
--- a/test/ecdsa.js
+++ b/test/ecdsa.js
@ -81,55 +81,6 @@ describe('ecdsa', function () {
    })
  })
  describe('recoverPubKey', function () {
    fixtures.valid.ecdsa.forEach(function (f) {
      it('recovers the pubKey for ' + f.d, function () {
        var d = BigInteger.fromHex(f.d)
        var Q = curve.G.multiply(d)
        var signature = ECSignature.fromDER(new Buffer(f.signature, 'hex'))
        var h1 = bcrypto.sha256(f.message)
        var e = BigInteger.fromBuffer(h1)
        var Qprime = ecdsa.recoverPubKey(e, signature, f.i)
        assert(Qprime.equals(Q))
      })
    })
    describe('with i ∈ {0,1,2,3}', function () {
      var hash = new Buffer('feef89995d7575f12d65ccc9d28ccaf7ab224c2e59dad4cc7f6a2b0708d24696', 'hex')
      var e = BigInteger.fromBuffer(hash)
      var signatureBuffer = new Buffer('INcvXVVEFyIfHLbDX+xoxlKFn3Wzj9g0UbhObXdMq+YMKC252o5RHFr0/cKdQe1WsBLUBi4morhgZ77obDJVuV0=', 'base64')
      var signature = ECSignature.parseCompact(signatureBuffer).signature
      var points = [
        '03e3a8c44a8bf712f1fbacee274fb19c0239b1a9e877eff0075ea335f2be8ff380',
        '0279be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798',
        '03d49e765f0bc27525c51a1b98fb1c99dacd59abe85a203af90f758260550b56c5',
        '027eea09d46ac7fb6aa2e96f9c576677214ffdc238eb167734a9b39d1eb4c3d30d'
      ]
      points.forEach(function (expectedHex, i) {
        it('recovers an expected point for i of ' + i, function () {
          var Qprime = ecdsa.recoverPubKey(e, signature, i)
          var QprimeHex = Qprime.getEncoded().toString('hex')
          assert.strictEqual(QprimeHex, expectedHex)
        })
      })
    })
    fixtures.invalid.recoverPubKey.forEach(function (f) {
      it('throws on ' + f.description + ' (' + f.exception + ')', function () {
        var e = BigInteger.fromHex(f.e)
        var signature = new ECSignature(new BigInteger(f.signatureRaw.r, 16), new BigInteger(f.signatureRaw.s, 16))
        assert.throws(function () {
          ecdsa.recoverPubKey(e, signature, f.i)
        }, new RegExp(f.exception))
      })
    })
  })
  describe('sign', function () {
    fixtures.valid.ecdsa.forEach(function (f) {
      it('produces a deterministic signature for "' + f.message + '"', function () {
--- a/test/fixtures/ecdsa.json
+++ b/test/fixtures/ecdsa.json
@ -125,78 +125,6 @@
    ]
  },
  "invalid": {
    "recoverPubKey": [
      {
        "description": "Invalid r value (< 0)",
        "exception": "Invalid r value",
        "e": "01",
        "signatureRaw": {
          "r": "-01",
          "s": "02"
        },
        "i": 0
      },
      {
        "description": "Invalid r value (== 0)",
        "exception": "Invalid r value",
        "e": "01",
        "signatureRaw": {
          "r": "00",
          "s": "02"
        },
        "i": 0
      },
      {
        "description": "Invalid s value (< 0)",
        "exception": "Invalid s value",
        "e": "01",
        "signatureRaw": {
          "r": "02",
          "s": "-01"
        },
        "i": 0
      },
      {
        "description": "Invalid s value (== 0)",
        "exception": "Invalid s value",
        "e": "01",
        "signatureRaw": {
          "r": "02",
          "s": "00"
        },
        "i": 0
      },
      {
        "description": "Invalid r value (nR is infinity)",
        "exception": "nR is not a valid curve point",
        "e": "01",
        "signatureRaw": {
          "r": "fffffffffffffffffffffffffffffffebaaedce6af48a03bbfd25e8cd0364140",
          "s": "01"
        },
        "i": 0
      },
      {
        "description": "Invalid curve point",
        "exception": "Point is not on the curve",
        "e": "01",
        "signatureRaw": {
          "r": "4b3b4ca85a86c47a098a223fffffffff",
          "s": "01"
        },
        "i": 0
      },
      {
        "description": "Invalid i value (> 3)",
        "exception": "Expected property \"2\" of type UInt2, got Number 4",
        "e": "01",
        "signatureRaw": {
          "r": "00",
          "s": "02"
        },
        "i": 4
      }
    ],
    "verify": [
      {
        "description": "The wrong signature",