rm ECSignature, add script.signature instead

src/ecdsa.js

@@ -3,14 +3,18 @@ var typeforce = require('typeforce')
 var types = require('./types')
 
 var BigInteger = require('bigi')
-var ECSignature = require('./ecsignature')
 
 var ZERO = new Buffer([0])
 var ONE = new Buffer([1])
 
 var ecurve = require('ecurve')
 var secp256k1 = ecurve.getCurveByName('secp256k1')
 
+var ECSignatureType = typeforce.compile({
+  r: types.BigInt,
+  s: types.BigInt
+})
+
 // https://tools.ietf.org/html/rfc6979#section-3.2
 function deterministicGenerateK (hash, x, checkSig) {
   typeforce(types.tuple(
@@ -105,13 +109,16 @@ function sign (hash, d) {
     s = n.subtract(s)
   }
 
-  return new ECSignature(r, s)
+  return {
+    r: r,
+    s: s
+  }
 }
 
 function verify (hash, signature, Q) {
   typeforce(types.tuple(
     types.Hash256bit,
-    types.ECSignature,
+    ECSignatureType,
     types.ECPoint
   ), arguments)
 
@@ -154,93 +161,8 @@ 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,
 

src/index.js

@@ -1,15 +1,13 @@
 module.exports = {
   Block: require('./block'),
   ECPair: require('./ecpair'),
-  ECSignature: require('./ecsignature'),
   HDNode: require('./hdnode'),
   Transaction: require('./transaction'),
   TransactionBuilder: require('./transaction_builder'),
 
   address: require('./address'),
   bufferutils: require('./bufferutils'),
   crypto: require('./crypto'),
-  message: require('./message'),
   networks: require('./networks'),
   opcodes: require('./opcodes.json'),
   script: require('./script')

src/script.js

@@ -373,6 +373,7 @@ module.exports = {
   toASM: toASM,
 
   number: require('./script_number'),
+  signature: require('./script_signature'),
 
   isCanonicalPubKey: isCanonicalPubKey,
   isCanonicalSignature: isCanonicalSignature,

src/script_signature.js

@@ -0,0 +1,40 @@
+var bip66 = require('bip66')
+var BigInteger = require('bigi')
+
+// BIP62: 1 byte hashType flag (only 0x01, 0x02, 0x03, 0x81, 0x82 and 0x83 are allowed)
+function decode (buffer) {
+  var hashType = buffer.readUInt8(buffer.length - 1)
+  var hashTypeMod = hashType & ~0x80
+  if (hashTypeMod <= 0 || hashTypeMod >= 4) throw new Error('Invalid hashType ' + hashType)
+
+  var decode = bip66.decode(buffer.slice(0, -1))
+
+  return {
+    signature: {
+      r: BigInteger.fromDERInteger(decode.r),
+      s: BigInteger.fromDERInteger(decode.s)
+    },
+    hashType: hashType
+  }
+}
+
+function encode (signature, hashType) {
+  var hashTypeMod = hashType & ~0x80
+  if (hashTypeMod <= 0 || hashTypeMod >= 4) throw new Error('Invalid hashType ' + hashType)
+
+  var hashTypeBuffer = new Buffer(1)
+  hashTypeBuffer.writeUInt8(hashType, 0)
+
+  var r = new Buffer(signature.r.toDERInteger())
+  var s = new Buffer(signature.s.toDERInteger())
+
+  return Buffer.concat([
+    bip66.encode(r, s),
+    hashTypeBuffer
+  ])
+}
+
+module.exports = {
+  decode: decode,
+  encode: encode
+}

src/transaction_builder.js

@@ -9,7 +9,6 @@ var typeforce = require('typeforce')
 var types = require('./types')
 
 var ECPair = require('./ecpair')
-var ECSignature = require('./ecsignature')
 var Transaction = require('./transaction')
 
 // re-orders signatures to match pubKeys, fills undefined otherwise
@@ -74,7 +73,7 @@ function extractInput (transaction, txIn, vin) {
         return result
 
       case 'pubkeyhash':
-        parsed = ECSignature.parseScriptSignature(scriptSigChunks[0])
+        parsed = bscript.signature.decode(scriptSigChunks[0])
         hashType = parsed.hashType
         pubKeys = scriptSigChunks.slice(1)
         signatures = [parsed.signature]
@@ -83,7 +82,7 @@ function extractInput (transaction, txIn, vin) {
         break
 
       case 'pubkey':
-        parsed = ECSignature.parseScriptSignature(scriptSigChunks[0])
+        parsed = bscript.signature.decode(scriptSigChunks[0])
         hashType = parsed.hashType
         signatures = [parsed.signature]
 
@@ -97,7 +96,7 @@ function extractInput (transaction, txIn, vin) {
         signatures = scriptSigChunks.slice(1).map(function (chunk) {
           if (chunk === ops.OP_0) return undefined
 
-          parsed = ECSignature.parseScriptSignature(chunk)
+          parsed = bscript.signature.decode(chunk)
           hashType = parsed.hashType
 
           return parsed.signature
@@ -308,18 +307,18 @@ function buildFromInputData (input, scriptType, parentType, redeemScript, allowI
 
   switch (scriptType) {
     case 'pubkeyhash':
-      var pkhSignature = input.signatures[0].toScriptSignature(input.hashType)
+      var pkhSignature = bscript.signature.encode(input.signatures[0], input.hashType)
       scriptSig = bscript.pubKeyHashInput(pkhSignature, input.pubKeys[0])
       break
 
     case 'pubkey':
-      var pkSignature = input.signatures[0].toScriptSignature(input.hashType)
+      var pkSignature = bscript.signature.encode(input.signatures[0], input.hashType)
       scriptSig = bscript.pubKeyInput(pkSignature)
       break
 
     case 'multisig':
       var msSignatures = input.signatures.map(function (signature) {
-        return signature && signature.toScriptSignature(input.hashType)
+        return signature && bscript.signature.encode(signature, input.hashType)
       })
 
       // fill in blanks with OP_0