From 3ba17a147945d66d2801e287d6e2e1b252035a5a Mon Sep 17 00:00:00 2001
From: Daniel Cousens <github@dcousens.com>
Date: Tue, 22 Aug 2017 11:43:48 +1000
Subject: [PATCH] TxBuilder: restrict uncompressed keyPairs for P2WPK and P2WSH

---
 src/transaction_builder.js             |  2 ++
 test/fixtures/transaction_builder.json | 24 +++++++++++++++++++++++-
 2 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/src/transaction_builder.js b/src/transaction_builder.js
index c450bd3..8eee5d0 100644
--- a/src/transaction_builder.js
+++ b/src/transaction_builder.js
@@ -693,6 +693,8 @@ TransactionBuilder.prototype.sign = function (vin, keyPair, redeemScript, hashTy
   var signed = input.pubKeys.some(function (pubKey, i) {
     if (!kpPubKey.equals(pubKey)) return false
     if (input.signatures[i]) throw new Error('Signature already exists')
+    if (!keyPair.compressed &&
+      input.signType === scriptTypes.P2WPKH) throw new Error('BIP143 rejects uncompressed public keys in P2WPKH or P2WSH')
 
     input.signatures[i] = keyPair.sign(signatureHash).toScriptSignature(hashType)
     return true
diff --git a/test/fixtures/transaction_builder.json b/test/fixtures/transaction_builder.json
index afee73b..4f05985 100644
--- a/test/fixtures/transaction_builder.json
+++ b/test/fixtures/transaction_builder.json
@@ -401,7 +401,6 @@
           }
         ]
       },
-
       {
         "description": "Transaction w/ P2WSH|P2PK -> P2PKH",
         "txHex": "010000000001014533a3bc1e039bd787656068e135aaee10aee95a64776bfc047ee6a7c1ebdd2f0000000000ffffffff0160ea0000000000001976a914851a33a5ef0d4279bd5854949174e2c65b1d450088ac02473044022039725bb7291a14dd182dafdeaf3ea0d5c05c34f4617ccbaa46522ca913995c4e02203b170d072ed2e489e7424ad96d8fa888deb530be2d4c5d9aaddf111a7efdb2d3012321038de63cf582d058a399a176825c045672d5ff8ea25b64d28d4375dcdb14c02b2bac00000000",
@@ -1838,6 +1837,29 @@
           }
         ]
       },
+      {
+        "exception": "BIP143 rejects uncompressed public keys in P2WPKH or P2WSH",
+        "inputs": [
+          {
+            "txId": "ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff",
+            "vout": 0,
+            "prevTxScript": "OP_0 15a71ffa7b5bb70cddefcf364494071022efe390",
+            "signs": [
+              {
+                "keyPair": "5JiHJJjdufSiMxbvnyNcKtQNLYH6SvUpQnRv9yZENFDWTQKQkzC",
+                "value": 10000,
+                "throws": true
+              }
+            ]
+          }
+        ],
+        "outputs": [
+          {
+            "script": "OP_0 aa4d7985c57e011a8b3dd8e0e5a73aaef41629c5",
+            "value": 10000
+          }
+        ]
+      },
       {
         "exception": "RedeemScript not supported \"OP_RETURN 06deadbeef03f895a2ad89fb6d696497af486cb7c644a27aa568c7a18dd06113401115185474\"",
         "inputs": [