From 9f62d6577cc116409ebee59c19402109990d1c6b Mon Sep 17 00:00:00 2001
From: audric <audric@loki.network>
Date: Tue, 27 Jul 2021 13:19:48 +1000
Subject: [PATCH] remove unused accessKey derived from profileKey

---
 js/modules/crypto.js      | 19 -------------------
 ts/models/conversation.ts | 23 -----------------------
 2 files changed, 42 deletions(-)

diff --git a/js/modules/crypto.js b/js/modules/crypto.js
index e7b543372..445fb49db 100644
--- a/js/modules/crypto.js
+++ b/js/modules/crypto.js
@@ -9,7 +9,6 @@ module.exports = {
   concatenateBytes,
   constantTimeEqual,
   decryptSymmetric,
-  deriveAccessKey,
   encryptAesCtr,
   encryptSymmetric,
   getRandomBytes,
@@ -27,13 +26,6 @@ function bytesFromString(string) {
 
 // High-level Operations
 
-async function deriveAccessKey(profileKey) {
-  const iv = getZeroes(12);
-  const plaintext = getZeroes(16);
-  const accessKey = await _encrypt_aes_gcm(profileKey, iv, plaintext);
-  return _getFirstBytes(accessKey, 16);
-}
-
 const IV_LENGTH = 16;
 const MAC_LENGTH = 16;
 const NONCE_LENGTH = 16;
@@ -141,17 +133,6 @@ async function encryptAesCtr(key, plaintext, counter) {
   return ciphertext;
 }
 
-async function _encrypt_aes_gcm(key, iv, plaintext) {
-  const algorithm = {
-    name: 'AES-GCM',
-    iv,
-  };
-  const extractable = false;
-
-  const cryptoKey = await crypto.subtle.importKey('raw', key, algorithm, extractable, ['encrypt']);
-  return crypto.subtle.encrypt(algorithm, cryptoKey, plaintext);
-}
-
 // Utility
 
 function getRandomBytes(n) {
diff --git a/ts/models/conversation.ts b/ts/models/conversation.ts
index d28515b14..ab3c6f25e 100644
--- a/ts/models/conversation.ts
+++ b/ts/models/conversation.ts
@@ -92,7 +92,6 @@ export interface ConversationAttributes {
   profile?: any;
   profileAvatar?: any;
   profileKey?: string;
-  accessKey?: any;
   triggerNotificationsFor: ConversationNotificationSettingType;
   isTrustedForAttachmentDownload: boolean;
   isPinned: boolean;
@@ -130,7 +129,6 @@ export interface ConversationAttributesOptionals {
   profile?: any;
   profileAvatar?: any;
   profileKey?: string;
-  accessKey?: any;
   triggerNotificationsFor?: ConversationNotificationSettingType;
   isTrustedForAttachmentDownload?: boolean;
   isPinned: boolean;
@@ -1201,34 +1199,13 @@ export class ConversationModel extends Backbone.Model<ConversationAttributes> {
     if (this.get('profileKey') !== profileKey) {
       this.set({
         profileKey,
-        accessKey: null,
       });
 
-      await this.deriveAccessKeyIfNeeded();
 
       await this.commit();
     }
   }
 
-  public async deriveAccessKeyIfNeeded() {
-    const profileKey = this.get('profileKey');
-    if (!profileKey) {
-      return;
-    }
-    if (this.get('accessKey')) {
-      return;
-    }
-
-    try {
-      const profileKeyBuffer = fromBase64ToArrayBuffer(profileKey);
-      const accessKeyBuffer = await window.Signal.Crypto.deriveAccessKey(profileKeyBuffer);
-      const accessKey = fromArrayBufferToBase64(accessKeyBuffer);
-      this.set({ accessKey });
-    } catch (e) {
-      window?.log?.warn(`Failed to derive access key for ${this.id}`);
-    }
-  }
-
   public async upgradeMessages(messages: any) {
     // tslint:disable-next-line: one-variable-per-declaration
     for (let max = messages.length, i = 0; i < max; i += 1) {