From 65698e7e454c4182904b6cf16d9a39fe94ad1bf3 Mon Sep 17 00:00:00 2001
From: Matias Alejo Garcia <ematiu@gmail.com>
Date: Tue, 29 Apr 2014 20:56:28 -0300
Subject: [PATCH] add cache for keys

---
 config.template.js          |  2 +-
 js/models/network/WebRTC.js | 24 +++++++++++++++++-------
 2 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/config.template.js b/config.template.js
index e614e7aa8..c065db489 100644
--- a/config.template.js
+++ b/config.template.js
@@ -17,7 +17,7 @@ var config = {
     maxPeers: 15,
 //    debug: 3,
     sjclParams: {
-      salt: 'cc295e13e14edcc0', // choose your own salt (hex string)
+      salt: 'mjuBtGybi/4=', // choose your own salt (base64)
       iter:500,
       mode:'ccm',
       ts:parseInt(64),   
diff --git a/js/models/network/WebRTC.js b/js/models/network/WebRTC.js
index e2aa0690d..f45eaa1f4 100644
--- a/js/models/network/WebRTC.js
+++ b/js/models/network/WebRTC.js
@@ -25,7 +25,7 @@ function Network(opts) {
   this.maxPeers       = opts.maxPeers || 10;
   this.opts           = { key: opts.key };
   this.sjclParams     = opts.sjclParams || {
-    salt: 'f28bfb49ef70573c',
+    salt: 'f28bfb49ef70573c', 
     iter:500,
     mode:'ccm',
     ts:parseInt(64),   
@@ -50,6 +50,7 @@ Network.prototype.cleanUp = function() {
   this.authenticatedPeers=[];
   this.copayerForPeer={};
   this.connections={};
+  this.keyCache={};
   if (this.peer) {
     console.log('## DESTROYING PEER INSTANCE'); //TODO
     this.peer.disconnect();
@@ -362,12 +363,22 @@ Network.prototype.getPeer = function() {
   return this.peer;
 };
 
+
+Network.prototype._keyForCopayerId = function(copayerId) {
+  var key=this.keyCache[copayerId];
+  if (key) return key;
+
+  var cBuf = new Buffer(copayerId,'hex');
+  var key = bitcore.util.sha256(cBuf).toString('base64');
+  this.keyCache[copayerId] = key;
+  return key;
+};
+
 Network.prototype._encryptFor = function(copayerId, payloadStr) {
-  var cBits= sjcl.codec.hex.toBits(copayerId);
-  var pass64= sjcl.codec.base64.fromBits(cBits);
+  var key = this._keyForCopayerId(copayerId);
   var plainText = sjcl.codec.utf8String.toBits(payloadStr);
   var p = this.sjclParams;    // auth strength
-  ct = sjcl.encrypt(pass64, plainText, p);//,p, rp);
+  ct = sjcl.encrypt(key, plainText, p);//,p, rp);
   var c = JSON.parse(ct);
   var toSend = {
     iv: c.iv,
@@ -383,9 +394,8 @@ Network.prototype._decrypt = function(encStr) {
     i[k] = this.sjclParams[k];
   }
   var str= JSON.stringify(i);
-  var cBits= sjcl.codec.hex.toBits(this.copayerId);
-  var pass64= sjcl.codec.base64.fromBits(cBits);
-  var pt = sjcl.decrypt(pass64, str);
+  var key= this._keyForCopayerId(this.copayerId);
+  var pt = sjcl.decrypt(key, str);
   return pt;
 };