From 34c367c49f4a7651c1d553f388eb4f26f9baa575 Mon Sep 17 00:00:00 2001
From: Abhinav Adduri <abhinadduri@gmail.com>
Date: Tue, 20 Jun 2017 14:33:28 -0700
Subject: [PATCH] added aad encryption

---
 frontend/src/fileReceiver.js |  8 ++++++--
 frontend/src/fileSender.js   |  5 ++++-
 frontend/src/utils.js        |  8 +++++++-
 server/portal_server.js      | 19 ++++++++++++++-----
 server/storage.js            | 22 +++++++++++++++++++++-
 5 files changed, 52 insertions(+), 10 deletions(-)

diff --git a/frontend/src/fileReceiver.js b/frontend/src/fileReceiver.js
index d7fb6a7a..68b651a3 100644
--- a/frontend/src/fileReceiver.js
+++ b/frontend/src/fileReceiver.js
@@ -1,5 +1,5 @@
 const EventEmitter = require('events');
-const { strToIv } = require('./utils');
+const { strToIv, strToUintArr } = require('./utils');
 
 const Raven = window.Raven;
 
@@ -36,6 +36,7 @@ class FileReceiver extends EventEmitter {
           fileReader.onload = function() {
             resolve({
               data: this.result,
+              aad: xhr.getResponseHeader('Additional-Data'),
               fname: xhr
                 .getResponseHeader('Content-Disposition')
                 .match(/=(.+)/)[1]
@@ -65,12 +66,15 @@ class FileReceiver extends EventEmitter {
       )
     ]).then(([fdata, key]) => {
       const salt = this.salt;
+      console.log(strToUintArr(fdata.aad));
+      
       return Promise.all([
         window.crypto.subtle.decrypt(
           {
             name: 'AES-GCM',
             iv: salt,
-            tagLength: 128
+            tagLength: 128,
+            additionalData: strToUintArr(fdata.aad)
           },
           key,
           fdata.data
diff --git a/frontend/src/fileSender.js b/frontend/src/fileSender.js
index ee64ddea..e8f0402e 100644
--- a/frontend/src/fileSender.js
+++ b/frontend/src/fileSender.js
@@ -8,6 +8,7 @@ class FileSender extends EventEmitter {
     super();
     this.file = file;
     this.iv = window.crypto.getRandomValues(new Uint8Array(12));
+    this.aad = window.crypto.getRandomValues(new Uint8Array(6));
   }
 
   static delete(fileId, token) {
@@ -60,7 +61,8 @@ class FileSender extends EventEmitter {
             {
               name: 'AES-GCM',
               iv: this.iv,
-              tagLength: 128
+              tagLength: 128,
+              additionalData: this.aad
             },
             secretKey,
             plaintext
@@ -77,6 +79,7 @@ class FileSender extends EventEmitter {
           const fd = new FormData();
           fd.append('fname', file.name);
           fd.append('data', blob, file.name);
+          fd.append('aad', this.aad);
 
           const xhr = new XMLHttpRequest();
 
diff --git a/frontend/src/utils.js b/frontend/src/utils.js
index f46b4f79..9f8f6f9b 100644
--- a/frontend/src/utils.js
+++ b/frontend/src/utils.js
@@ -20,6 +20,7 @@ function strToIv(str) {
   return iv;
 }
 
+
 function notify(str) {
   if (!('Notification' in window)) {
     return;
@@ -32,8 +33,13 @@ function notify(str) {
   }
 }
 
+function strToUintArr(str) {
+  return new Uint8Array(str.split(",").map(x => parseInt(x)));
+}
+
 module.exports = {
   ivToStr,
   strToIv,
-  notify
+  notify,
+  strToUintArr
 };
diff --git a/server/portal_server.js b/server/portal_server.js
index 75317117..c966e882 100644
--- a/server/portal_server.js
+++ b/server/portal_server.js
@@ -78,14 +78,17 @@ app.get('/assets/download/:id', (req, res) => {
     return;
   }
 
-  storage
-    .filename(id)
-    .then(reply => {
+  Promise.all([
+    storage.filename(id),
+    storage.aad(id)])
+    .then(([reply, aad]) => {
       storage.length(id).then(contentLength => {
+        
         res.writeHead(200, {
           'Content-Disposition': 'attachment; filename=' + reply,
           'Content-Type': 'application/octet-stream',
-          'Content-Length': contentLength
+          'Content-Length': contentLength,
+          'Additional-Data': aad
         });
         const file_stream = storage.get(id);
 
@@ -142,16 +145,22 @@ app.post('/upload/:id', (req, res, next) => {
   }
 
   req.pipe(req.busboy);
+  
+  req.busboy.on('field', (fieldname, value) => {
+    storage.setField(req.params.id, fieldname, value);
+  })
+
   req.busboy.on('file', (fieldname, file, filename) => {
     log.info('Uploading:', req.params.id);
 
     const protocol = conf.env === 'production' ? 'https' : req.protocol;
     const url = `${protocol}://${req.get('host')}/download/${req.params.id}/`;
-
     storage.set(req.params.id, file, filename, url).then(linkAndID => {
       res.json(linkAndID);
     });
   });
+
+
 });
 
 app.get('/__lbheartbeat__', (req, res) => {
diff --git a/server/storage.js b/server/storage.js
index dedf0040..f90d4f07 100644
--- a/server/storage.js
+++ b/server/storage.js
@@ -27,6 +27,8 @@ if (conf.s3_bucket) {
     length: awsLength,
     get: awsGet,
     set: awsSet,
+    aad: aad,
+    setField: setField,
     delete: awsDelete,
     forceDelete: awsForceDelete,
     ping: awsPing
@@ -38,6 +40,8 @@ if (conf.s3_bucket) {
     length: localLength,
     get: localGet,
     set: localSet,
+    aad: aad,
+    setField: setField,
     delete: localDelete,
     forceDelete: localForceDelete,
     ping: localPing
@@ -68,6 +72,22 @@ function exists(id) {
   });
 }
 
+function setField(id, key, value) {
+  redis_client.hset(id, key, value);
+}
+
+function aad(id) {
+  return new Promise((resolve, reject) => {
+    redis_client.hget(id, 'aad', (err, reply) => {
+      if (!err) {
+        resolve(reply);
+      } else {
+        reject();
+      }
+    })
+  })
+}
+
 function localLength(id) {
   return new Promise((resolve, reject) => {
     try {
@@ -86,7 +106,7 @@ function localSet(id, file, filename, url) {
   return new Promise((resolve, reject) => {
     const fstream = fs.createWriteStream(path.join(__dirname, '../static', id));
     file.pipe(fstream);
-    fstream.on('close', () => {
+    fstream.on('close', () => {      
       const uuid = crypto.randomBytes(10).toString('hex');
 
       redis_client.hmset([id, 'filename', filename, 'delete', uuid]);