HDNode: enforces sane seed lengths and Transaction input

src/hdnode.js

@@ -51,6 +51,10 @@ HDNode.HIGHEST_BIT = 0x80000000
 HDNode.LENGTH = 78
 
 HDNode.fromSeedBuffer = function(seed, network) {
+  assert(Buffer.isBuffer(seed), 'Expected Buffer, got' + seed)
+  assert(seed.length >= 16, 'Seed should be at least 128 bits')
+  assert(seed.length <= 64, 'Seed should be at most 512 bits')
+
   var I = crypto.HmacSHA512(seed, HDNode.MASTER_SECRET)
   var IL = I.slice(0, 32)
   var IR = I.slice(32)

src/transaction.js

@@ -84,9 +84,11 @@ Transaction.prototype.addOutput = function(scriptPubKey, value) {
     scriptPubKey = address.toOutputScript()
   }
 
+  assert(scriptPubKey instanceof Script, 'Expected Address or Script, got ' + scriptPubKey)
+
   return (this.outs.push({
     script: scriptPubKey,
-    value: value,
+    value: value
   }) - 1)
 }
 

test/hdnode.js

@@ -65,6 +65,18 @@ describe('HDNode', function() {
         assert.equal(hd.chainCode.toString('hex'), f.master.chainCode)
       })
     })
+
+    it('throws on low entropy seed', function() {
+      assert.throws(function() {
+        HDNode.fromSeedHex('ffffffffff')
+      }, /Seed should be at least 128 bits/)
+    })
+
+    it('throws on too high entropy seed', function() {
+      assert.throws(function() {
+        HDNode.fromSeedHex('ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff')
+      }, /Seed should be at most 512 bits/)
+    })
   })
 
   describe('toBase58', function() {