TxBuilder: remove initialized field from signature inputs

src/transaction_builder.js

@@ -33,60 +33,51 @@ function extractInput(txIn) {
   }
 
   // Extract hashType, pubKeys and signatures
-  var hashType, initialized, parsed, pubKeys, signatures
+  var hashType, parsed, pubKeys, signatures
 
   switch (scriptType) {
-    case 'pubkeyhash':
+    case 'pubkeyhash': {
       parsed = ECSignature.parseScriptSignature(scriptSig.chunks[0])
       hashType = parsed.hashType
       pubKeys = [ECPubKey.fromBuffer(scriptSig.chunks[1])]
       signatures = [parsed.signature]
-
-      initialized = true
       prevOutScript = pubKeys[0].getAddress().toOutputScript()
 
       break
+    }
 
-    case 'multisig':
-      signatures = scriptSig.chunks.slice(1).map(function(chunk) {
-        if (chunk === ops.OP_0) return chunk
-
-        var parsed = ECSignature.parseScriptSignature(chunk)
-        hashType = parsed.hashType
-
-        return parsed.signature
-      })
-
-      if (redeemScript) {
-        pubKeys = redeemScript.chunks.slice(1, -2).map(ECPubKey.fromBuffer)
-      }
-
-      break
-
-    case 'pubkey':
+    case 'pubkey': {
       parsed = ECSignature.parseScriptSignature(scriptSig.chunks[0])
       hashType = parsed.hashType
       signatures = [parsed.signature]
 
-      initialized = true
-
       if (redeemScript) {
         pubKeys = [ECPubKey.fromBuffer(redeemScript.chunks[0])]
       }
 
       break
+    }
+
+    case 'multisig': {
+      signatures = scriptSig.chunks.slice(1).map(function(chunk) {
+        if (chunk === ops.OP_0) return chunk
+
+        var parsed = ECSignature.parseScriptSignature(chunk)
+        hashType = parsed.hashType
+
+        return parsed.signature
+      })
 
-    default:
       if (redeemScript) {
-        initialized = true
+        pubKeys = redeemScript.chunks.slice(1, -2).map(ECPubKey.fromBuffer)
       }
 
       break
+    }
   }
 
   return {
     hashType: hashType,
-    initialized: initialized,
     prevOutScript: prevOutScript,
     prevOutType: prevOutType,
     pubKeys: pubKeys,
@@ -222,38 +213,40 @@ TransactionBuilder.prototype.__build = function(allowIncomplete) {
     var scriptSig
 
     if (!allowIncomplete) {
-      assert(input.initialized, 'Transaction is not complete')
+      assert(!!scriptType, 'Transaction is not complete')
       assert(scriptType in canSignTypes, scriptType + ' not supported')
       assert(input.signatures, 'Transaction is missing signatures')
     }
 
-    switch (scriptType) {
-      case 'pubkeyhash':
-        var pkhSignature = input.signatures[0].toScriptSignature(input.hashType)
-        scriptSig = scripts.pubKeyHashInput(pkhSignature, input.pubKeys[0])
-        break
+    if (input.signatures) {
+      switch (scriptType) {
+        case 'pubkeyhash':
+          var pkhSignature = input.signatures[0].toScriptSignature(input.hashType)
+          scriptSig = scripts.pubKeyHashInput(pkhSignature, input.pubKeys[0])
+          break
 
-      case 'multisig':
-        // Array.prototype.map is sparse-compatible
-        var msSignatures = input.signatures.map(function(signature) {
-          return signature.toScriptSignature(input.hashType)
-        })
+        case 'multisig':
+          // Array.prototype.map is sparse-compatible
+          var msSignatures = input.signatures.map(function(signature) {
+            return signature.toScriptSignature(input.hashType)
+          })
 
-        // fill in blanks with OP_0
-        for (var i = 0; i < msSignatures.length; ++i) {
-          if (msSignatures[i]) continue
+          // fill in blanks with OP_0
+          for (var i = 0; i < msSignatures.length; ++i) {
+            if (msSignatures[i]) continue
 
-          msSignatures[i] = ops.OP_0
-        }
+            msSignatures[i] = ops.OP_0
+          }
 
-        var redeemScript = allowIncomplete ? undefined : input.redeemScript
-        scriptSig = scripts.multisigInput(signatures, redeemScript)
-        break
+          var redeemScript = allowIncomplete ? undefined : input.redeemScript
+          scriptSig = scripts.multisigInput(msSignatures, redeemScript)
+          break
 
-      case 'pubkey':
-        var pkSignature = input.signatures[0].toScriptSignature(input.hashType)
-        scriptSig = scripts.pubKeyInput(pkSignature)
-        break
+        case 'pubkey':
+          var pkSignature = input.signatures[0].toScriptSignature(input.hashType)
+          scriptSig = scripts.pubKeyInput(pkSignature)
+          break
+      }
     }
 
     // if we built a scriptSig, wrap as scriptHash if necessary
@@ -277,18 +270,19 @@ TransactionBuilder.prototype.sign = function(index, privKey, redeemScript, hashT
     assert.equal(input.hashType, hashType, 'Inconsistent hashType')
   }
 
+  var initialized = input.prevOutScript &&
+                    input.prevOutType &&
+                    input.hashType &&
+                    input.pubKeys &&
+                    input.signatures
+
   // are we already initialized?
-  if (input.initialized) {
+  if (initialized) {
     // redeemScript only needed to initialize, but if provided again, enforce consistency
     if (redeemScript) {
       assert.deepEqual(input.redeemScript, redeemScript, 'Inconsistent redeemScript')
     }
 
-    // if signatures already exist, enforce multisig scriptType
-    if (input.signatures.length > 0) {
-      assert.equal(input.scriptType, 'multisig', input.scriptType + ' doesn\'t support multiple signatures')
-    }
-
   // initialize it
   } else {
     if (redeemScript) {
@@ -344,26 +338,24 @@ TransactionBuilder.prototype.sign = function(index, privKey, redeemScript, hashT
     }
 
     input.hashType = hashType
-    input.initialized = true
     input.signatures = input.signatures || []
   }
 
   // do we know how to sign this?
   assert(input.scriptType in canSignTypes, input.scriptType + ' not supported')
 
-  var signatureScript = input.redeemScript || input.prevOutScript
-  var signatureHash = this.tx.hashForSignature(index, signatureScript, hashType)
-  var signature = privKey.sign(signatureHash)
-
-  // enforce signing in order of public keys
+  // enforce in order signing of public keys
   assert(input.pubKeys.some(function(pubKey, i) {
     if (!privKey.pub.Q.equals(pubKey.Q)) return false
 
     assert(!input.signatures[i], 'Signature already exists')
+    var signatureScript = input.redeemScript || input.prevOutScript
+    var signatureHash = this.tx.hashForSignature(index, signatureScript, hashType)
+    var signature = privKey.sign(signatureHash)
     input.signatures[i] = signature
 
     return true
-  }), 'privateKey cannot sign for this input')
+  }, this), 'privateKey cannot sign for this input')
 }
 
 module.exports = TransactionBuilder

test/fixtures/transaction_builder.json

@@ -206,7 +206,7 @@
       },
       {
         "description": "Incomplete transaction w/ prevTxScript defined",
-        "exception": "Transaction is not complete",
+        "exception": "Transaction is missing signatures",
         "alwaysThrows": true,
         "inputs": [
           {
@@ -240,7 +240,8 @@
     ],
     "sign": [
       {
-        "exception": "pubkeyhash doesn\\'t support multiple signatures",
+        "description": "Too many signatures - pubKeyHash",
+        "exception": "Signature already exists",
         "inputs": [
           {
             "txId": "ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff",
@@ -406,6 +407,7 @@
         ]
       },
       {
+        "description": "Too many signatures - scriptHash(multisig 1-of-1)",
         "exception": "Signature already exists",
         "inputs": [
           {
@@ -418,7 +420,6 @@
               },
               {
                 "privKey": "KwDiBf89QgGbjEhKnhXJuH7LrciVrZi3qYjgd9M7rFU73sVHnoWn",
-                "redeemScript": "OP_1 0479be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798483ada7726a3c4655da4fbfc0e1108a8fd17b448a68554199c47d08ffb10d4b8 OP_1 OP_CHECKMULTISIG",
                 "throws": true
               }
             ]