From d47ced1199f1bd00896628f40ef2ee5a85bf3207 Mon Sep 17 00:00:00 2001
From: lilia <liliakai@gmail.com>
Date: Tue, 20 Jun 2017 17:21:55 -0700
Subject: [PATCH] Don't recompute outgoing message padding

We can use the same padded plaintext across multiple numbers or attempts rather
than re-creating it every time we encrypt to a particular number.

// FREEBIE
---
 js/libtextsecure.js               | 23 +++++++++++++++--------
 libtextsecure/outgoing_message.js | 23 +++++++++++++++--------
 2 files changed, 30 insertions(+), 16 deletions(-)

diff --git a/js/libtextsecure.js b/js/libtextsecure.js
index fc06cae33d19..eb111990fd1f 100644
--- a/js/libtextsecure.js
+++ b/js/libtextsecure.js
@@ -38798,20 +38798,27 @@ OutgoingMessage.prototype = {
         return messagePartCount * 160;
     },
 
+    getPlaintext: function() {
+        if (!this.plaintext) {
+            var messageBuffer = this.message.toArrayBuffer();
+            this.plaintext = new Uint8Array(
+                this.getPaddedMessageLength(messageBuffer.byteLength + 1) - 1
+            );
+            this.plaintext.set(new Uint8Array(messageBuffer));
+            this.plaintext[messageBuffer.byteLength] = 0x80;
+        }
+        return this.plaintext;
+    },
+
     doSendMessage: function(number, deviceIds, recurse) {
         var ciphers = {};
-        var plaintext = this.message.toArrayBuffer();
-        var paddedPlaintext = new Uint8Array(
-            this.getPaddedMessageLength(plaintext.byteLength + 1) - 1
-        );
-        paddedPlaintext.set(new Uint8Array(plaintext));
-        paddedPlaintext[plaintext.byteLength] = 0x80;
+        var plaintext = this.getPlaintext();
 
         return Promise.all(deviceIds.map(function(deviceId) {
             var address = new libsignal.SignalProtocolAddress(number, deviceId);
-            var sessionCipher =  new libsignal.SessionCipher(textsecure.storage.protocol, address);
+            var sessionCipher = new libsignal.SessionCipher(textsecure.storage.protocol, address);
             ciphers[address.getDeviceId()] = sessionCipher;
-            return sessionCipher.encrypt(paddedPlaintext).then(function(ciphertext) {
+            return sessionCipher.encrypt(plaintext).then(function(ciphertext) {
                 return {
                     type                      : ciphertext.type,
                     destinationDeviceId       : address.getDeviceId(),
diff --git a/libtextsecure/outgoing_message.js b/libtextsecure/outgoing_message.js
index 446085637357..f7322323dab1 100644
--- a/libtextsecure/outgoing_message.js
+++ b/libtextsecure/outgoing_message.js
@@ -119,20 +119,27 @@ OutgoingMessage.prototype = {
         return messagePartCount * 160;
     },
 
+    getPlaintext: function() {
+        if (!this.plaintext) {
+            var messageBuffer = this.message.toArrayBuffer();
+            this.plaintext = new Uint8Array(
+                this.getPaddedMessageLength(messageBuffer.byteLength + 1) - 1
+            );
+            this.plaintext.set(new Uint8Array(messageBuffer));
+            this.plaintext[messageBuffer.byteLength] = 0x80;
+        }
+        return this.plaintext;
+    },
+
     doSendMessage: function(number, deviceIds, recurse) {
         var ciphers = {};
-        var plaintext = this.message.toArrayBuffer();
-        var paddedPlaintext = new Uint8Array(
-            this.getPaddedMessageLength(plaintext.byteLength + 1) - 1
-        );
-        paddedPlaintext.set(new Uint8Array(plaintext));
-        paddedPlaintext[plaintext.byteLength] = 0x80;
+        var plaintext = this.getPlaintext();
 
         return Promise.all(deviceIds.map(function(deviceId) {
             var address = new libsignal.SignalProtocolAddress(number, deviceId);
-            var sessionCipher =  new libsignal.SessionCipher(textsecure.storage.protocol, address);
+            var sessionCipher = new libsignal.SessionCipher(textsecure.storage.protocol, address);
             ciphers[address.getDeviceId()] = sessionCipher;
-            return sessionCipher.encrypt(paddedPlaintext).then(function(ciphertext) {
+            return sessionCipher.encrypt(plaintext).then(function(ciphertext) {
                 return {
                     type                      : ciphertext.type,
                     destinationDeviceId       : address.getDeviceId(),