Added support for AES128/HMAC-SHA256 login tokens and online token generation.

Ylian Saint-Hilaire committed Dec 28, 2018 at 21:55 UTC caed053d2de04b4d7cda6259d7bcb8effc841174
3 files changed +66 -16
meshcentral.js
+43 -15
@@ -58,7 +58,7 @@ function CreateMeshCentralServer(config, args) {
58 obj.maintenanceTimer = null;
59 obj.serverId = null;
60 obj.currentVer = null;
61 - obj.serverKey = new Buffer(obj.crypto.randomBytes(32), 'binary');
61 + obj.serverKey = new Buffer(obj.crypto.randomBytes(48), 'binary');
62 obj.loginCookieEncryptionKey = null;
63 obj.serverSelfWriteAllowed = true;
64 try { obj.currentVer = JSON.parse(obj.fs.readFileSync(obj.path.join(__dirname, 'package.json'), 'utf8')).version; } catch (e) { } // Fetch server version
@@ -528,7 +528,7 @@ function CreateMeshCentralServer(config, args) {
528 // Load the login cookie encryption key from the database if allowed
529 if ((obj.config) && (obj.config.settings) && (obj.config.settings.allowlogintoken == true)) {
530 obj.db.Get('LoginCookieEncryptionKey', function (err, docs) {
531 - if ((docs.length > 0) && (docs[0].key != null) && (obj.args.logintokengen == null)) {
531 + if ((docs.length > 0) && (docs[0].key != null) && (obj.args.logintokengen == null) && (docs[0].key.length >= 96)) {
532 obj.loginCookieEncryptionKey = Buffer.from(docs[0].key, 'hex');
533 } else {
534 obj.loginCookieEncryptionKey = obj.generateCookieKey(); obj.db.Set({ _id: 'LoginCookieEncryptionKey', key: obj.loginCookieEncryptionKey.toString('hex'), time: Date.now() });
@@ -1067,7 +1067,7 @@ function CreateMeshCentralServer(config, args) {
1067 } else {
1068 // Load the login cookie encryption key from the database
1069 obj.db.Get('LoginCookieEncryptionKey', function (err, docs) {
1070 - if ((docs.length > 0) && (docs[0].key != null) && (obj.args.logintokengen == null)) {
1070 + if ((docs.length > 0) && (docs[0].key != null) && (obj.args.logintokengen == null) && (docs[0].key.length >= 96)) {
1071 // Key is present, use it.
1072 obj.loginCookieEncryptionKey = Buffer.from(docs[0].key, 'hex');
1073 func(obj.encodeCookie({ u: userid, a: 3 }, obj.loginCookieEncryptionKey));
@@ -1081,11 +1081,11 @@ function CreateMeshCentralServer(config, args) {
1081 });
1082 };
1083
1084 - // Show the yser login token generation key
1084 + // Show the user login token generation key
1085 obj.showLoginTokenKey = function (func) {
1086 // Load the login cookie encryption key from the database
1087 obj.db.Get('LoginCookieEncryptionKey', function (err, docs) {
1088 - if ((docs.length > 0) && (docs[0].key != null) && (obj.args.logintokengen == null)) {
1088 + if ((docs.length > 0) && (docs[0].key != null) && (obj.args.logintokengen == null) && (docs[0].key.length >= 96)) {
1089 // Key is present, use it.
1090 func(docs[0].key);
1091 } else {
@@ -1098,30 +1098,36 @@ function CreateMeshCentralServer(config, args) {
1098
1099 // Generate a cryptographic key used to encode and decode cookies
1100 obj.generateCookieKey = function () {
1101 - return new Buffer(obj.crypto.randomBytes(32), 'binary');
1102 - //return Buffer.alloc(32, 0); // Sets the key to zeros, debug only.
1101 + return new Buffer(obj.crypto.randomBytes(48), 'binary');
1102 + //return Buffer.alloc(48, 0); // Sets the key to zeros, debug only.
1103 };
1104
1105 - // Encode an object as a cookie using a key. (key must be 32 bytes long)
1105 + // Encode an object as a cookie using a key using AES-GCM. (key must be 32 bytes or more)
1106 obj.encodeCookie = function (o, key) {
1107 try {
1108 if (key == null) { key = obj.serverKey; }
1109 o.time = Math.floor(Date.now() / 1000); // Add the cookie creation time
1110 - var iv = new Buffer(obj.crypto.randomBytes(12), 'binary'), cipher = obj.crypto.createCipheriv('aes-256-gcm', key, iv);
1111 - var crypted = Buffer.concat([cipher.update(JSON.stringify(o), 'utf8'), cipher.final()]);
1112 - var cookie = Buffer.concat([iv, cipher.getAuthTag(), crypted]).toString('base64').replace(/\+/g, '@').replace(/\//g, '$');
1113 - return cookie;
1110 + const iv = new Buffer(obj.crypto.randomBytes(12), 'binary'), cipher = obj.crypto.createCipheriv('aes-256-gcm', key.slice(0, 32), iv);
1111 + const crypted = Buffer.concat([cipher.update(JSON.stringify(o), 'utf8'), cipher.final()]);
1112 + return Buffer.concat([iv, cipher.getAuthTag(), crypted]).toString('base64').replace(/\+/g, '@').replace(/\//g, '$');
1113 } catch (e) { return null; }
1114 };
1115
1117 - // Decode a cookie back into an object using a key. Return null if it's not a valid cookie. (key must be 32 bytes long)
1116 + // Decode a cookie back into an object using a key using AES-GCM or AES128-CBC/HMAC-SHA386. Return null if it's not a valid cookie. (key must be 32 bytes or more)
1117 obj.decodeCookie = function (cookie, key, timeout) {
1118 + const r = obj.decodeCookieAESGCM(cookie, key, timeout);
1119 + if (r == null) { return obj.decodeCookieAESSHA(cookie, key, timeout); }
1120 + return r;
1121 + }
1122 +
1123 + // Decode a cookie back into an object using a key using AES-GCM. Return null if it's not a valid cookie. (key must be 32 bytes or more)
1124 + obj.decodeCookieAESGCM = function (cookie, key, timeout) {
1125 try {
1126 if (key == null) { key = obj.serverKey; }
1127 cookie = new Buffer(cookie.replace(/\@/g, '+').replace(/\$/g, '/'), 'base64');
1122 - var decipher = obj.crypto.createDecipheriv('aes-256-gcm', key, cookie.slice(0, 12));
1128 + const decipher = obj.crypto.createDecipheriv('aes-256-gcm', key.slice(0, 32), cookie.slice(0, 12));
1129 decipher.setAuthTag(cookie.slice(12, 16));
1124 - var o = JSON.parse(decipher.update(cookie.slice(28), 'binary', 'utf8') + decipher.final('utf8'));
1130 + const o = JSON.parse(decipher.update(cookie.slice(28), 'binary', 'utf8') + decipher.final('utf8'));
1131 if ((o.time == null) || (o.time == null) || (typeof o.time != 'number')) { Debug(1, 'ERR: Bad cookie due to invalid time'); return null; }
1132 o.time = o.time * 1000; // Decode the cookie creation time
1133 o.dtime = Date.now() - o.time; // Decode how long ago the cookie was created (in milliseconds)
@@ -1131,6 +1137,28 @@ function CreateMeshCentralServer(config, args) {
1137 } catch (e) { return null; }
1138 };
1139
1140 + // Decode a cookie back into an object using a key using AES128 / HMAC-SHA256. Return null if it's not a valid cookie. (key must be 48 bytes or more)
1141 + // We do this because poor .NET does not support AES-GCM.
1142 + obj.decodeCookieAESSHA = function (cookie, key, timeout) {
1143 + try {
1144 + if (key == null) { key = obj.serverKey; }
1145 + if (key.length < 48) return null;
1146 + cookie = new Buffer(cookie.replace(/\@/g, '+').replace(/\$/g, '/'), 'base64');
1147 + const decipher = obj.crypto.createDecipheriv('aes-128-cbc', key.slice(32, 48), cookie.slice(0, 16));
1148 + const rawmsg = decipher.update(cookie.slice(16), 'binary', 'binary') + decipher.final('binary');
1149 + const hmac = obj.crypto.createHmac('sha256', key.slice(0, 32));
1150 + hmac.update(rawmsg.slice(32));
1151 + if (Buffer.compare(hmac.digest(), Buffer.from(rawmsg.slice(0, 32))) == false) { return null; }
1152 + const o = JSON.parse(rawmsg.slice(32).toString('utf8'));
1153 + if ((o.time == null) || (o.time == null) || (typeof o.time != 'number')) { Debug(1, 'ERR: Bad cookie due to invalid time'); return null; }
1154 + o.time = o.time * 1000; // Decode the cookie creation time
1155 + o.dtime = Date.now() - o.time; // Decode how long ago the cookie was created (in milliseconds)
1156 + if (timeout == null) { timeout = 2; }
1157 + if ((o.dtime > (timeout * 60000)) || (o.dtime < -30000)) { obj.debug(1, 'ERR: Bad cookie due to timeout'); return null; } // The cookie is only valid 120 seconds, or 30 seconds back in time (in case other server's clock is not quite right)
1158 + return o;
1159 + } catch (ex) { console.log(ex); return null; }
1160 + };
1161 +
1162 // Debug
1163 obj.debug = function (lvl) {
1164 if (lvl > obj.debugLevel) return;
package.json
+1 -1
@@ -1,6 +1,6 @@
1 {
2 "name": "meshcentral",
3 - "version": "0.2.5-e",
3 + "version": "0.2.5-f",
4 "keywords": [
5 "Remote Management",
6 "Intel AMT",
webserver.js
+22
@@ -1922,6 +1922,28 @@ module.exports.CreateWebServer = function (parent, db, args, certificates) {
1922 try { obj.meshAgentHandler.CreateMeshAgent(obj, obj.db, ws, req, obj.args, getDomain(req)); } catch (e) { console.log(e); }
1923 });
1924
1925 + // Creates a login token using the user/pass that is passed in as URL arguments.
1926 + // For example: https://localhost/createLoginToken.ashx?user=admin&pass=admin&a=3
1927 + // It's not advised to use this to create login tokens since the URL is often logged and you got credentials in the URL.
1928 + // However, people want it so here it is.
1929 + obj.app.get(url + 'createLoginToken.ashx', function (req, res) {
1930 + // A web socket session can be authenticated in many ways (Default user, session, user/pass and cookie). Check authentication here.
1931 + if ((req.query.user != null) && (req.query.pass != null)) {
1932 + // A user/pass is provided in URL arguments
1933 + obj.authenticate(req.query.user, req.query.pass, getDomain(req), function (err, userid) {
1934 + if ((err == null) && (obj.users[userid])) {
1935 + // User is authenticated, create a token
1936 + var x = { a: 3 }; for (var i in req.query) { if ((i != 'user') && (i != 'pass')) { x[i] = obj.common.toNumber(req.query[i]); } } x.u = userid;
1937 + res.send(obj.parent.encodeCookie(x, obj.parent.loginCookieEncryptionKey));
1938 + } else {
1939 + res.sendStatus(404);
1940 + }
1941 + });
1942 + } else {
1943 + res.sendStatus(404);
1944 + }
1945 + });
1946 +
1947 obj.app.get(url + 'stop', function (req, res) { res.send('Stopping Server, <a href="' + url + '">click here to login</a>.'); setTimeout(function () { parent.Stop(); }, 500); });
1948
1949 // Indicates to ExpressJS that the public folder should be used to serve static files.