refactoring of password change and preparations for server side encryption

public/javascripts/encryption.js

@@ -131,11 +131,9 @@ const encryption = (function() {
     function resetEncryptionSession() {
         dataKey = null;
 
-        if (noteEditor.getCurrentNote().detail.encryption > 0) {
-            // most secure solution - guarantees nothing remained in memory
-            // since this expires because user doesn't use the app, it shouldn't be disruptive
-            window.location.reload(true);
-        }
+        // most secure solution - guarantees nothing remained in memory
+        // since this expires because user doesn't use the app, it shouldn't be disruptive
+        window.location.reload(true);
     }
 
     function isEncryptionAvailable() {

routes/api/login.js

@@ -6,8 +6,11 @@ const options = require('../../services/options');
 const utils = require('../../services/utils');
 const migration = require('../../services/migration');
 const SOURCE_ID = require('../../services/source_id');
+const auth = require('../../services/auth');
+const password_encryption = require('../../services/password_encryption');
+const protected_session = require('../../services/protected_session');
 
-router.post('', async (req, res, next) => {
+router.post('/sync', async (req, res, next) => {
     const timestamp = req.body.timestamp;
 
     const now = utils.nowTimestamp();
@@ -41,4 +44,25 @@ router.post('', async (req, res, next) => {
     });
 });
 
+// this is for entering protected mode so user has to be already logged-in (that's the reason we don't require username)
+router.post('protected', auth.checkApiAuth, async (req, res, next) => {
+    const password = req.body.password;
+
+    if (!await password_encryption.verifyPassword(password)) {
+        return {
+            success: false,
+            message: "Given current password doesn't match hash"
+        };
+    }
+
+    const decryptedDataKey = password_encryption.getDecryptedDataKey(password);
+
+    const protectedSessionId = protected_session.setDataKey(req, decryptedDataKey);
+
+    res.send({
+        success: true,
+        protectedSessionId: protectedSessionId
+    });
+});
+
 module.exports = router;

routes/api/migration.js

@@ -8,8 +8,8 @@ const migration = require('../../services/migration');
 
 router.get('', auth.checkApiAuthWithoutMigration, async (req, res, next) => {
     res.send({
-        'db_version': parseInt(await options.getOption('db_version')),
-        'app_db_version': migration.APP_DB_VERSION
+        db_version: parseInt(await options.getOption('db_version')),
+        app_db_version: migration.APP_DB_VERSION
     });
 });
 
@@ -17,7 +17,7 @@ router.post('', auth.checkApiAuthWithoutMigration, async (req, res, next) => {
     const migrations = await migration.migrate();
 
     res.send({
-        'migrations': migrations
+        migrations: migrations
     });
 });
 

services/change_password.js

@@ -5,52 +5,22 @@ const options = require('./options');
 const my_scrypt = require('./my_scrypt');
 const utils = require('./utils');
 const audit_category = require('./audit_category');
-const crypto = require('crypto');
-const aesjs = require('./aes');
+const password_encryption = require('./password_encryption');
 
 async function changePassword(currentPassword, newPassword, req) {
-    const current_password_hash = utils.toBase64(await my_scrypt.getVerificationHash(currentPassword));
-
-    if (current_password_hash !== await options.getOption('password_verification_hash')) {
+    if (!await password_encryption.verifyPassword(currentPassword)) {
         return {
-            'success': false,
-            'message': "Given current password doesn't match hash"
+            success: false,
+            message: "Given current password doesn't match hash"
         };
     }
 
-    const currentPasswordDerivedKey = await my_scrypt.getPasswordDerivedKey(currentPassword);
-
     const newPasswordVerificationKey = utils.toBase64(await my_scrypt.getVerificationHash(newPassword));
-    const newPasswordEncryptionKey = await my_scrypt.getPasswordDerivedKey(newPassword);
-
-    function decrypt(encryptedBase64) {
-        const encryptedBytes = utils.fromBase64(encryptedBase64);
-
-        const aes = getAes(currentPasswordDerivedKey);
-        return aes.decrypt(encryptedBytes).slice(4);
-    }
-
-    function encrypt(plainText) {
-        const aes = getAes(newPasswordEncryptionKey);
-
-        const plainTextBuffer = Buffer.from(plainText, 'latin1');
-
-        const digest = crypto.createHash('sha256').update(plainTextBuffer).digest().slice(0, 4);
-
-        const encryptedBytes = aes.encrypt(Buffer.concat([digest, plainTextBuffer]));
-
-        return utils.toBase64(encryptedBytes);
-    }
-
-    function getAes(key) {
-        return new aesjs.ModeOfOperation.ctr(key, new aesjs.Counter(5));
-    }
-
-    const encryptedDataKey = await options.getOption('encrypted_data_key');
+    const newPasswordDerivedKey = await my_scrypt.getPasswordDerivedKey(newPassword);
 
-    const decryptedDataKey = decrypt(encryptedDataKey);
+    const decryptedDataKey = await password_encryption.getDecryptedDataKey(currentPassword);
 
-    const newEncryptedDataKey = encrypt(decryptedDataKey);
+    const newEncryptedDataKey = password_encryption.encryptDataKey(newPasswordDerivedKey, decryptedDataKey);
 
     await sql.doInTransaction(async () => {
         await options.setOption('encrypted_data_key', newEncryptedDataKey);
@@ -61,8 +31,8 @@ async function changePassword(currentPassword, newPassword, req) {
     });
 
     return {
-        'success': true,
-        'new_encrypted_data_key': newEncryptedDataKey
+        success: true,
+        new_encrypted_data_key: newEncryptedDataKey
     };
 }
 

services/password_encryption.js

@@ -0,0 +1,53 @@
+const options = require('./options');
+const my_scrypt = require('./my_scrypt');
+const utils = require('./utils');
+const crypto = require('crypto');
+const aesjs = require('./aes');
+
+async function verifyPassword(password) {
+    const givenPasswordHash = utils.toBase64(await my_scrypt.getVerificationHash(password));
+
+    const dbPasswordHash = await options.getOption('password_verification_hash');
+
+    return givenPasswordHash === dbPasswordHash;
+}
+
+function decryptDataKey(passwordDerivedKey, encryptedBase64) {
+    const encryptedBytes = utils.fromBase64(encryptedBase64);
+
+    const aes = getAes(passwordDerivedKey);
+    return aes.decrypt(encryptedBytes).slice(4);
+}
+
+function encryptDataKey(passwordDerivedKey, plainText) {
+    const aes = getAes(passwordDerivedKey);
+
+    const plainTextBuffer = Buffer.from(plainText, 'latin1');
+
+    const digest = crypto.createHash('sha256').update(plainTextBuffer).digest().slice(0, 4);
+
+    const encryptedBytes = aes.encrypt(Buffer.concat([digest, plainTextBuffer]));
+
+    return utils.toBase64(encryptedBytes);
+}
+
+async function getDecryptedDataKey(password) {
+    const passwordDerivedKey = await my_scrypt.getPasswordDerivedKey(password);
+
+    const encryptedDataKey = await options.getOption('encrypted_data_key');
+
+    const decryptedDataKey = decryptDataKey(passwordDerivedKey, encryptedDataKey);
+
+    return decryptedDataKey;
+}
+
+function getAes(key) {
+    return new aesjs.ModeOfOperation.ctr(key, new aesjs.Counter(5));
+}
+
+module.exports = {
+    verifyPassword,
+    decryptDataKey,
+    encryptDataKey,
+    getDecryptedDataKey
+};

services/protected_session.js

@@ -0,0 +1,22 @@
+const utils = require('./utils');
+
+function setDataKey(req, decryptedDataKey) {
+    req.session.decryptedDataKey = decryptedDataKey;
+    req.session.protectedSessionId = utils.randomSecureToken(32);
+
+    return req.session.protectedSessionId;
+}
+
+function getDataKey(req, protectedSessionId) {
+    if (protectedSessionId && req.session.protectedSessionId === protectedSessionId) {
+        return req.session.decryptedDataKey;
+    }
+    else {
+        return null;
+    }
+}
+
+module.exports = {
+    setDataKey,
+    getDataKey
+};

services/sync.js

@@ -82,7 +82,7 @@ async function login() {
 
     const syncContext = { cookieJar: rp.jar() };
 
-    const resp = await syncRequest(syncContext, 'POST', '/api/login', {
+    const resp = await syncRequest(syncContext, 'POST', '/api/login/sync', {
         timestamp: timestamp,
         dbVersion: migration.APP_DB_VERSION,
         hash: hash