From 8334fa56993321d1e2945713f06ee5b298b81d37 Mon Sep 17 00:00:00 2001
From: lilia <liliakai@gmail.com>
Date: Wed, 16 Nov 2016 17:03:01 +0100
Subject: [PATCH] Double the max old ratchet list length

Attempt to mitigate Bad MAC errors due to repeated ciphertext from more
than 5 exchanges ago.
---
 dist/libsignal-protocol.js | 5 +++--
 src/SessionRecord.js       | 5 +++--
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/dist/libsignal-protocol.js b/dist/libsignal-protocol.js
index bf97ef8..13353bc 100644
--- a/dist/libsignal-protocol.js
+++ b/dist/libsignal-protocol.js
@@ -35515,6 +35515,7 @@ Internal.ChainType = {
 Internal.SessionRecord = function() {
     'use strict';
     var ARCHIVED_STATES_MAX_LENGTH = 40;
+    var OLD_RATCHETS_MAX_LENGTH = 10;
     var SESSION_RECORD_VERSION = 'v1';
 
     var StaticByteBufferProto = new dcodeIO.ByteBuffer().__proto__;
@@ -35747,8 +35748,8 @@ Internal.SessionRecord = function() {
         removeOldChains: function(session) {
             // Sending ratchets are always removed when we step because we never need them again
             // Receiving ratchets are added to the oldRatchetList, which we parse
-            // here and remove all but the last five.
-            while (session.oldRatchetList.length > 5) {
+            // here and remove all but the last ten.
+            while (session.oldRatchetList.length > OLD_RATCHETS_MAX_LENGTH) {
                 var index = 0;
                 var oldest = session.oldRatchetList[0];
                 for (var i = 0; i < session.oldRatchetList.length; i++) {
diff --git a/src/SessionRecord.js b/src/SessionRecord.js
index cb6d4dc..c0cb3e6 100644
--- a/src/SessionRecord.js
+++ b/src/SessionRecord.js
@@ -16,6 +16,7 @@ Internal.ChainType = {
 Internal.SessionRecord = function() {
     'use strict';
     var ARCHIVED_STATES_MAX_LENGTH = 40;
+    var OLD_RATCHETS_MAX_LENGTH = 10;
     var SESSION_RECORD_VERSION = 'v1';
 
     var StaticByteBufferProto = new dcodeIO.ByteBuffer().__proto__;
@@ -248,8 +249,8 @@ Internal.SessionRecord = function() {
         removeOldChains: function(session) {
             // Sending ratchets are always removed when we step because we never need them again
             // Receiving ratchets are added to the oldRatchetList, which we parse
-            // here and remove all but the last five.
-            while (session.oldRatchetList.length > 5) {
+            // here and remove all but the last ten.
+            while (session.oldRatchetList.length > OLD_RATCHETS_MAX_LENGTH) {
                 var index = 0;
                 var oldest = session.oldRatchetList[0];
                 for (var i = 0; i < session.oldRatchetList.length; i++) {