Merge pull request #7 from sachaaaaa/fallback_decrypt

Decrypt "friend request" messages using fallback encryption. Move logic into libloki.js

.eslintignore

@@ -12,6 +12,7 @@ test/views/*.js
 # Generated files
 js/components.js
 js/libtextsecure.js
+js/libloki.js
 js/util_worker.js
 js/libsignal-protocol-worker.js
 libtextsecure/components.js

.gitignore

@@ -19,6 +19,7 @@ sql/
 js/components.js
 js/util_worker.js
 js/libtextsecure.js
+js/libloki.js
 libtextsecure/components.js
 libtextsecure/test/test.js
 stylesheets/*.css

.prettierignore

@@ -8,6 +8,7 @@ dist/**
 js/components.js
 js/util_worker.js
 js/libtextsecure.js
+js/libloki.js
 libtextsecure/components.js
 libtextsecure/test/test.js
 stylesheets/*.css

Gruntfile.js

@@ -86,6 +86,12 @@ module.exports = grunt => {
         ],
         dest: 'js/libtextsecure.js',
       },
+      libloki: {
+        src: [
+          'libloki/libloki-protocol.js',
+        ],
+        dest: 'js/libloki.js',
+      },
       libtextsecuretest: {
         src: [
           'node_modules/jquery/dist/jquery.js',
@@ -128,6 +134,10 @@ module.exports = grunt => {
         files: ['./libtextsecure/*.js', './libtextsecure/storage/*.js'],
         tasks: ['concat:libtextsecure'],
       },
+      libloki: {
+        files: ['./libloki/*.js'],
+        tasks: ['concat:libloki'],
+      },
       protobuf: {
         files: ['./protos/SignalService.proto'],
         tasks: ['exec:build-protobuf'],

background.html

@@ -584,6 +584,7 @@
   <script type='text/javascript' src='js/storage.js'></script>
   <script type='text/javascript' src='js/signal_protocol_store.js'></script>
   <script type='text/javascript' src='js/libtextsecure.js'></script>
+  <script type='text/javascript' src='js/libloki.js'></script>
 
   <script type='text/javascript' src='js/focus_listener.js'></script>
   <script type='text/javascript' src='js/notifications.js'></script>

libloki/libloki-protocol.js

@@ -0,0 +1,47 @@
+/* global window, libsignal, textsecure */
+
+// eslint-disable-next-line func-names
+(function() {
+  window.libloki = window.libloki || {};
+
+  const IV_LENGTH = 16;
+
+  FallBackSessionCipher = function (address) {
+    this.pubKey = StringView.hexToArrayBuffer(address.getName());
+
+    this.encrypt = async (plaintext) => {
+      const myKeyPair = await textsecure.storage.protocol.getIdentityKeyPair();
+      const myPrivateKey = myKeyPair.privKey;
+      const symmetricKey = libsignal.Curve.calculateAgreement(this.pubKey, myPrivateKey);
+      const iv = libsignal.crypto.getRandomBytes(IV_LENGTH);
+      const ciphertext = await libsignal.crypto.encrypt(symmetricKey, plaintext, iv);
+      const ivAndCiphertext = new Uint8Array(
+        iv.byteLength + ciphertext.byteLength
+      );
+      ivAndCiphertext.set(new Uint8Array(iv));
+      ivAndCiphertext.set(
+        new Uint8Array(ciphertext),
+        iv.byteLength
+      );
+
+      return {
+          type           : 6, //friend request
+          body           : new dcodeIO.ByteBuffer.wrap(ivAndCiphertext).toString('binary'),
+          registrationId : null
+      };
+    },
+
+    this.decrypt = async (ivAndCiphertext) => {
+      const iv = ivAndCiphertext.slice(0, IV_LENGTH);
+      const cipherText = ivAndCiphertext.slice(IV_LENGTH);
+      const myKeyPair = await textsecure.storage.protocol.getIdentityKeyPair();
+      const myPrivateKey = myKeyPair.privKey;
+      const symmetricKey = libsignal.Curve.calculateAgreement(this.pubKey, myPrivateKey);
+      const plaintext = await libsignal.crypto.decrypt(symmetricKey, cipherText, iv);
+      return plaintext;
+    }
+  }
+  
+  window.libloki.FallBackSessionCipher = FallBackSessionCipher;
+
+})();

libtextsecure/message_receiver.js

@@ -646,10 +646,17 @@ MessageReceiver.prototype.extend({
       case textsecure.protobuf.Envelope.Type.CIPHERTEXT:
         window.log.info('message from', this.getEnvelopeId(envelope));
         promise = Promise.resolve(ciphertext.toArrayBuffer())//;sessionCipher
-          // TODO: restore decryption & unpadding
+          // TODO: restore decryption & unpadding (?)
           //.decryptWhisperMessage(ciphertext)
           //.then(this.unpad);
         break;
+      case textsecure.protobuf.Envelope.Type.FRIEND_REQUEST:
+        window.log.info('friend-request message from ', envelope.source)
+        const fallBackSessionCipher = new libloki.FallBackSessionCipher(
+          address
+        );
+        promise = fallBackSessionCipher.decrypt(ciphertext.toArrayBuffer());
+        break;
       case textsecure.protobuf.Envelope.Type.PREKEY_BUNDLE:
         window.log.info('prekey message from', this.getEnvelopeId(envelope));
         promise = this.decryptPreKeyWhisperMessage(

libtextsecure/outgoing_message.js

@@ -1,4 +1,4 @@
-/* global textsecure, libsignal, window, btoa */
+/* global textsecure, libsignal, window, btoa, libloki */
 
 /* eslint-disable more/no-then */
 
@@ -209,7 +209,7 @@ OutgoingMessage.prototype = {
       content: outgoingObject.content,
     });
     const requestMessage = new textsecure.protobuf.WebSocketRequestMessage({
-        id: new Uint8Array(libsignal.crypto.getRandomBytes(1))[0],
+        id: new Uint8Array(libsignal.crypto.getRandomBytes(1))[0], // random ID for now
         verb: 'PUT',
         path: '/api/v1/message',
         body: messageEnvelope.encode().toArrayBuffer()
@@ -219,6 +219,7 @@ OutgoingMessage.prototype = {
       request: requestMessage
     });
     const bytes = new Uint8Array(websocketMessage.encode().toArrayBuffer())
+    bytes.toString(); // print bytes for debugging purposes: can be injected in mock socket server 
     return bytes;
   },
   doSendMessage(number, deviceIds, recurse) {
@@ -239,32 +240,7 @@ OutgoingMessage.prototype = {
 
         let sessionCipher;
         if (this.fallBackEncryption) {
-          // TODO: move to own file?
-          FallBackSessionCipher = function (address) {
-            this.recipientPubKey = StringView.hexToArrayBuffer(address.getName());
-            this.encrypt = async (plaintext) => {
-              const myKeyPair = await textsecure.storage.protocol.getIdentityKeyPair();
-              const myPrivateKey = myKeyPair.privKey;
-              const symmetricKey = libsignal.Curve.calculateAgreement(this.recipientPubKey, myPrivateKey);
-              const iv = libsignal.crypto.getRandomBytes(16);
-              const ciphertext = await libsignal.crypto.encrypt(symmetricKey, plaintext, iv);
-              const ivAndCiphertext = new Uint8Array(
-                iv.byteLength + ciphertext.byteLength
-              );
-              ivAndCiphertext.set(new Uint8Array(iv));
-              ivAndCiphertext.set(
-                new Uint8Array(ciphertext),
-                iv.byteLength
-              );
-
-              return {
-                  type           : 6, //friend request
-                  body           : new dcodeIO.ByteBuffer.wrap(ivAndCiphertext).toString('binary'),
-                  registrationId : null
-              };
-            }
-          }
-          sessionCipher = new FallBackSessionCipher(
+          sessionCipher = new libloki.FallBackSessionCipher(
             address
           );
         } else {

mockup_servers/socket_server.py

@@ -13,9 +13,11 @@ async def hello(websocket, path):
     # protomessage = new textsecure.protobuf.WebSocketMessage({type: textsecure.protobuf.WebSocketMessage.Type.REQUEST, request: {id:99, verb:'PUT', path:'/api/v1/queue/empty', body:null }})
     # new Uint8Array(protomessage.encode().toArrayBuffer())
     message =           bytes(
-        #[8, 1, 18, 70, 10, 3, 80, 85, 84, 18, 15, 47, 97, 112, 105, 47, 118, 49, 47, 109, 101, 115, 115, 97, 103, 101, 26, 44, 8, 1, 18, 15, 109, 121, 115, 111, 117, 114, 99, 101, 97, 100, 100, 114, 101, 115, 115, 56, 1, 40, 184, 151, 213, 221, 5, 66, 15, 10, 13, 10, 11, 104, 101, 108, 108, 111, 32, 119, 111, 114, 108, 100, 32, 99]
         [
-            8,1,18,117,10,3,80,85,84,18,15,47,97,112,105,47,118,49,47,109,101,115,115,97,103,101,26,91,8,1,18,66,48,53,55,51,57,102,51,54,55,50,100,55,57,52,51,56,101,57,53,53,97,55,99,99,55,55,56,52,100,98,97,53,101,97,52,98,102,56,50,55,52,54,54,53,55,55,51,99,97,102,51,101,97,98,55,48,97,50,98,57,100,98,102,101,50,99,56,1,40,0,66,15,10,13,10,11,104,101,108,108,111,32,119,111,114,108,100,32,99
+            # "hello world" - unencrypted
+            #8,1,18,117,10,3,80,85,84,18,15,47,97,112,105,47,118,49,47,109,101,115,115,97,103,101,26,91,8,1,18,66,48,53,55,51,57,102,51,54,55,50,100,55,57,52,51,56,101,57,53,53,97,55,99,99,55,55,56,52,100,98,97,53,101,97,52,98,102,56,50,55,52,54,54,53,55,55,51,99,97,102,51,101,97,98,55,48,97,50,98,57,100,98,102,101,50,99,56,1,40,0,66,15,10,13,10,11,104,101,108,108,111,32,119,111,114,108,100,32,99
+            # "test" - fall back encrypted
+            8,1,18,140,1,10,3,80,85,84,18,15,47,97,112,105,47,118,49,47,109,101,115,115,97,103,101,26,113,8,6,18,66,48,53,51,102,48,101,57,56,54,53,97,100,101,54,97,100,57,48,48,97,54,99,101,51,98,98,54,101,102,97,99,102,102,102,97,98,99,50,56,49,101,53,97,50,102,100,102,54,101,97,49,51,57,98,51,48,51,50,49,55,57,57,97,97,50,99,56,1,40,181,202,171,141,229,44,66,32,147,127,63,203,38,142,133,120,28,115,7,150,230,26,166,28,182,199,199,182,11,101,80,48,252,232,108,164,8,236,98,50,32,150,1
         ])
     # created by executing in js:
     # dataMessage = new textsecure.protobuf.DataMessage({body: "hello world", attachments:[], contact:[]})

ts/util/lint/linter.ts

@@ -52,6 +52,7 @@ const excludedFiles = [
   // Generated files
   '^js/components.js',
   '^js/libtextsecure.js',
+  '^js/libloki.js',
   '^js/util_worker.js',
   '^libtextsecure/components.js',
   '^libtextsecure/test/test.js',