From 46969c6f3a514981cc4c71ba77aa648fc58253c4 Mon Sep 17 00:00:00 2001
From: Christopher Jeffrey <chjjeffrey@gmail.com>
Date: Fri, 22 Jul 2016 21:57:42 -0700
Subject: [PATCH] bip70: fix signing.

---
 lib/bcoin/bip70/index.js | 45 ++++++++++++++++++++++------------------
 lib/bcoin/bip70/x509.js  | 17 +++++++++++++++
 2 files changed, 42 insertions(+), 20 deletions(-)

diff --git a/lib/bcoin/bip70/index.js b/lib/bcoin/bip70/index.js
index c56dc505..c6891220 100644
--- a/lib/bcoin/bip70/index.js
+++ b/lib/bcoin/bip70/index.js
@@ -55,7 +55,7 @@ PaymentRequest.prototype.fromOptions = function fromOptions(options) {
   }
 
   if (options.chain)
-    this.setChain(this.pkiType, options.chain);
+    this.setChain(options.chain);
 
   return this;
 };
@@ -122,7 +122,7 @@ PaymentRequest.prototype.getAlgorithm = function getAlgorithm() {
   if (parts[1] !== 'sha1' && parts[1] !== 'sha256')
     return;
 
-  return { key: 'rsa', hash: parts[1] };
+  return { key: parts[0], hash: parts[1] };
 };
 
 PaymentRequest.prototype.signatureData = function signatureData() {
@@ -144,20 +144,21 @@ PaymentRequest.prototype.signatureHash = function signatureHash() {
   return utils.hash(alg.hash, this.signatureData());
 };
 
-PaymentRequest.prototype.setChain = function setChain(pkiType, chain) {
+PaymentRequest.prototype.setChain = function setChain(chain) {
   var p = new ProtoWriter();
-  var i, cert;
+  var i, cert, pem;
 
-  assert(pkiType === 'x509+sha1' || pkiType === 'x509+sha256');
-  assert(Array.isArray(chain));
-
-  this.pkiType = pkiType;
+  if (!Array.isArray(chain))
+    chain = [chain];
 
   for (i = 0; i < chain.length; i++) {
     cert = chain[i];
-    if (typeof cert === 'string')
-      cert = asn1.fromPEM(cert).data;
-    assert(Buffer.isBuffer(cert), 'Bad cert format.');
+    if (typeof cert === 'string') {
+      pem = asn1.fromPEM(cert);
+      assert(pem.type === 'certificate', 'Bad certificate PEM.');
+      cert = pem.data;
+    }
+    assert(Buffer.isBuffer(cert), 'Certificates must be PEM or DER.');
     p.writeFieldBytes(1, cert);
   }
 
@@ -179,24 +180,26 @@ PaymentRequest.prototype.getChain = function getChain() {
   return chain;
 };
 
-PaymentRequest.prototype.sign = function sign(key) {
-  var alg, msg;
+PaymentRequest.prototype.sign = function sign(key, chain) {
+  var alg, msg, chain;
 
-  if (!this.pkiType || this.pkiType === 'none') {
-    this.signature = null;
-    return;
-  }
+  if (chain)
+    this.setChain(chain);
+
+  if (!this.pkiType)
+    this.pkiType = 'x509+sha256';
 
   alg = this.getAlgorithm();
   assert(alg, 'No hash algorithm available.');
 
   msg = this.signatureData();
+  chain = this.getChain();
 
-  this.signature = x509.sign(alg.hash, msg, key);
+  this.signature = x509.signSubject(alg.hash, msg, key, chain);
 };
 
 PaymentRequest.prototype.verify = function verify() {
-  var alg, msg, ver, der, pem;
+  var alg, msg, sig, chain;
 
   if (!this.pkiType || this.pkiType === 'none')
     return true;
@@ -210,8 +213,10 @@ PaymentRequest.prototype.verify = function verify() {
     return false;
 
   msg = this.signatureData();
+  sig = this.signature;
+  chain = this.getChain();
 
-  return x509.verifySubject(alg.hash, msg, this.signature, this.getChain());
+  return x509.verifySubject(alg.hash, msg, sig, chain);
 };
 
 PaymentRequest.prototype.verifyChain = function verifyChain(ignoreTime) {
diff --git a/lib/bcoin/bip70/x509.js b/lib/bcoin/bip70/x509.js
index 41a70624..42f82cc3 100644
--- a/lib/bcoin/bip70/x509.js
+++ b/lib/bcoin/bip70/x509.js
@@ -126,6 +126,23 @@ x509.verifyTime = function verifyTime(cert) {
   return now > time.notBefore && now < time.notAfter;
 };
 
+x509.signSubject = function signSubject(hash, msg, key, chain) {
+  var cert, alg;
+
+  assert(chain.length !== 0, 'No chain available.');
+
+  cert = x509.parse(chain[0]);
+  assert(cert, 'Could not parse certificate.');
+
+  alg = x509.getKeyAlgorithm(cert);
+  assert(alg, 'Certificate uses an unknown algorithm.');
+
+  if (Buffer.isBuffer(key))
+    key = asn1.toPEM(key, alg.key + ' PRIVATE KEY');
+
+  return x509.sign(alg.key, hash, msg, key);
+};
+
 x509.verifySubject = function verifySubject(hash, msg, sig, chain) {
   var cert, key, alg;