From cf20326e98d8c6356a2260295c6005268b98c292 Mon Sep 17 00:00:00 2001
From: Christopher Jeffrey <chjjeffrey@gmail.com>
Date: Mon, 7 Dec 2015 14:12:42 -0800
Subject: [PATCH] verify sighash types other than `all`.

---
 lib/bcoin/script.js | 26 +++++++++++++-------------
 lib/bcoin/tx.js     | 27 +++++++++++++++++----------
 2 files changed, 30 insertions(+), 23 deletions(-)

diff --git a/lib/bcoin/script.js b/lib/bcoin/script.js
index ecd21535..d0785fac 100644
--- a/lib/bcoin/script.js
+++ b/lib/bcoin/script.js
@@ -128,7 +128,7 @@ script.verify = function verify(hash, sig, pub) {
   }
 };
 
-script.execute = function execute(s, stack, tx) {
+script.execute = function execute(s, stack, hasher) {
   if (s.length > 10000) {
     return false;
   }
@@ -160,20 +160,20 @@ script.execute = function execute(s, stack, tx) {
       }
 
     } else if (o === 'checksigverify' || o === 'checksig') {
-      if (!tx || stack.length < 2)
+      if (!hasher || stack.length < 2)
         return false;
 
       var pub = stack.pop();
       var sig = stack.pop();
       var type = sig[sig.length - 1];
-      if (type !== 1)
+      if (!constants.rhashType[type & 0x7f])
         return false;
 
-      // XXX Deal with different hashTypes besides `all`
-      // if (typeof tx === 'function')
-      //   tx = tx(constants.rhashType[type]);
+      var hash = hasher;
+      if (typeof hash === 'function')
+        hash = hash(type);
 
-      var res = script.verify(tx, sig.slice(0, -1), pub);
+      var res = script.verify(hash, sig.slice(0, -1), pub);
       if (o === 'checksigverify') {
         if (!res)
           return false;
@@ -181,7 +181,7 @@ script.execute = function execute(s, stack, tx) {
         stack.push(res ? [ 1 ] : []);
       }
     } else if (o === 'checkmultisigverify' || o === 'checkmultisig') {
-      if (!tx || stack.length < 3)
+      if (!hasher || stack.length < 3)
         return false;
 
       var n = stack.pop();
@@ -214,16 +214,16 @@ script.execute = function execute(s, stack, tx) {
       for (var i = 0, j = 0; i < m && j < n; i++) {
         var sig = stack.pop();
         var type = sig[sig.length - 1];
-        if (type !== 1)
+        if (!constants.rhashType[type & 0x7f])
           return false;
 
-        // XXX Deal with different hashTypes besides `all`
-        // if (typeof tx === 'function')
-        //   tx = tx(constants.rhashType[type]);
+        var hash = hasher;
+        if (typeof hash === 'function')
+          hash = hash(type);
 
         var res = false;
         for (; !res && j < n; j++)
-          res = script.verify(tx, sig.slice(0, -1), keys[j]);
+          res = script.verify(hash, sig.slice(0, -1), keys[j]);
         if (res)
           succ++;
       }
diff --git a/lib/bcoin/tx.js b/lib/bcoin/tx.js
index e1f879dd..74d9cea3 100644
--- a/lib/bcoin/tx.js
+++ b/lib/bcoin/tx.js
@@ -124,6 +124,12 @@ TX.prototype._inputIndex = function _inputIndex(hash, index) {
 };
 
 TX.prototype.signature = function(input, key, type) {
+  if (!type)
+    type = 'all';
+
+  if (typeof type === 'string')
+    type = bcoin.protocol.constants.hashType[type];
+
   // Get the previous output's subscript
   var s = input.out.tx.getSubscript(input.out.index);
 
@@ -134,7 +140,7 @@ TX.prototype.signature = function(input, key, type) {
   var signature = bcoin.ecdsa.sign(hash, key).toDER();
 
   // Add the sighash as a single byte to the signature
-  signature = signature.concat(constants.hashType[type]);
+  signature = signature.concat(type);
 
   return signature;
 };
@@ -187,6 +193,9 @@ TX.prototype.signInput = function(input, key, type) {
   if (!type)
     type = 'all';
 
+  if (typeof type === 'string')
+    type = bcoin.protocol.constants.hashType[type];
+
   // Get the previous output's subscript
   var s = input.out.tx.getSubscript(input.out.index);
 
@@ -197,7 +206,7 @@ TX.prototype.signInput = function(input, key, type) {
   var signature = bcoin.ecdsa.sign(hash, key).toDER();
 
   // Add the sighash as a single byte to the signature
-  signature = signature.concat(constants.hashType[type]);
+  signature = signature.concat(type);
 
   // P2PKH and simple tx
   if (bcoin.script.isPubkeyhash(s) || bcoin.script.isSimplePubkeyhash(s)) {
@@ -329,13 +338,14 @@ TX.prototype.getSubscript = function getSubscript(index) {
 TX.prototype.subscriptHash = function subscriptHash(index, s, type) {
   var copy = this.clone();
 
+  if (typeof type === 'string')
+    type = bcoin.protocol.constants.hashType[type];
+
   copy.inputs.forEach(function(input, i) {
     input.script = index === i ? s : [];
   });
   var verifyStr = copy.render();
-  verifyStr = verifyStr.concat(
-    bcoin.protocol.constants.hashType[type], 0, 0, 0
-  );
+  utils.writeU32(verifyStr, type, verifyStr.length);
   var hash = utils.dsha256(verifyStr);
 
   return hash;
@@ -356,15 +366,12 @@ TX.prototype.verify = function verify(index, force) {
     assert(input.out.tx.outputs.length > input.out.index);
 
     var subscript = input.out.tx.getSubscript(input.out.index);
-    var hash = this.subscriptHash(i, subscript, 'all');
-
-    // XXX Deal with different hashTypes besides `all`
-    // var hash = this.subscriptHash.bind(this, i, subscript);
+    var hasher = this.subscriptHash.bind(this, i, subscript);
 
     var stack = [];
     bcoin.script.execute(input.script, stack);
     var prev = input.out.tx.outputs[input.out.index].script;
-    var res = bcoin.script.execute(prev, stack, hash);
+    var res = bcoin.script.execute(prev, stack, hasher);
     if (!res)
       return false;