* Disconnect clients that attempt to login with banned usernames for Telnet as well

* Slow disconnects to thwart brute force attacks - these names won't exist anyway,
  but we want the attacking client to not DoS us

WHATSNEW.md

@@ -25,6 +25,7 @@ This document attempts to track **major** changes and additions in ENiGMA½. For
 * NNTP support! See [NNTP docs](/docs/servers/nntp.md) for more information.
 * `oputil.js user rm` and `oputil.js user info` are in! See [oputil CLI](/docs/admin/oputil.md).
 * Performing a file scan/import using `oputil.js fb scan` now recognizes various `FILES.BBS` formats.
+* Usernames found in the `config.users.badUserNames` are now not only disallowed from applying, but disconnected at any login attempt.
 
 
 ## 0.0.8-alpha

core/servers/login/ssh.js

@@ -57,39 +57,46 @@ function SSHClient(clientConn) {
             }
         };
 
-        function terminateConnection() {
+        const terminateConnection = () => {
             safeContextReject();
             return clientConn.end();
-        }
+        };
 
-        function promptAndTerm(msg) {
+        //  slow version to thwart brute force attacks
+        const slowTerminateConnection = () => {
+            setTimeout( () => {
+                return terminateConnection();
+            }, 2000);
+        };
+
+        const promptAndTerm = (msg, method = 'standard') => {
             if('keyboard-interactive' === ctx.method) {
                 ctx.prompt(msg);
             }
-            return terminateConnection();
+            return 'slow' === method ? slowTerminateConnection() : terminateConnection();
-        }
+        };
 
-        function accountAlreadyLoggedIn(username) {
+        const accountAlreadyLoggedIn = (username) => {
             return promptAndTerm(`${username} is already connected to the system. Terminating connection.\n(Press any key to continue)`);
-        }
+        };
 
-        function accountDisabled(username) {
+        const accountDisabled = (username) => {
             return promptAndTerm(`${username} is disabled.\n(Press any key to continue)`);
-        }
+        };
 
-        function accountInactive(username) {
+        const accountInactive = (username) => {
             return promptAndTerm(`${username} is waiting for +op activation.\n(Press any key to continue)`);
-        }
+        };
 
-        function accountLocked(username) {
+        const accountLocked = (username) => {
-            return promptAndTerm(`${username} is locked.\n(Press any key to continue)`);
+            return promptAndTerm(`${username} is locked.\n(Press any key to continue)`, 'slow');
-        }
+        };
 
-        function isSpecialHandleError(err) {
+        const isSpecialHandleError = (err) => {
             return [ ErrorReasons.AlreadyLoggedIn, ErrorReasons.Disabled, ErrorReasons.Inactive, ErrorReasons.Locked ].includes(err.reasonCode);
-        }
+        };
 
-        function handleSpecialError(err, username) {
+        const handleSpecialError = (err, username) => {
             switch(err.reasonCode) {
                 case ErrorReasons.AlreadyLoggedIn   : return accountAlreadyLoggedIn(username);
                 case ErrorReasons.Inactive          : return accountInactive(username);
@@ -97,7 +104,7 @@ function SSHClient(clientConn) {
                 case ErrorReasons.Locked            : return accountLocked(username);
                 default                             : return terminateConnection();
             }
-        }
+        };
 
         //
         //  If the system is open and |isNewUser| is true, the login
@@ -115,7 +122,7 @@ function SSHClient(clientConn) {
                     }
 
                     if(Errors.BadLogin().code === err.code) {
-                        return terminateConnection();
+                        return slowTerminateConnection();
                     }
 
                     return safeContextReject(SSHClient.ValidAuthMethods);
@@ -143,7 +150,7 @@ function SSHClient(clientConn) {
                         }
 
                         if(Errors.BadLogin().code === err.code) {
-                            return terminateConnection();
+                            return slowTerminateConnection();
                         }
 
                         const artOpts = {

core/system_menu_method.js

@@ -34,6 +34,11 @@ function login(callingMenu, formData, extraArgs, cb) {
                 return callingMenu.gotoMenu(callingMenu.menuConfig.config.tooNodeMenu, cb);
             }
 
+            //  banned username results in disconnect
+            if(ErrorReasons.NotAllowed === err.reasonCode) {
+                return logoff(callingMenu, {}, {}, cb);
+            }
+
             const ReasonsMenus = [
                 ErrorReasons.TooMany, ErrorReasons.Disabled, ErrorReasons.Inactive, ErrorReasons.Locked
             ];

core/user_login.js

@@ -27,7 +27,11 @@ function userLogin(client, username, password, cb) {
 
     if(config.users.badUserNames.includes(username.toLowerCase())) {
         client.log.info( { username : username }, 'Attempt to login with banned username');
-        return cb(Errors.BadLogin(ErrorReasons.NotAllowed));
+
+        //  slow down a bit to thwart brute force attacks
+        return setTimeout( () => {
+            return cb(Errors.BadLogin('Disallowed username', ErrorReasons.NotAllowed));
+        }, 2000);
     }
 
     client.user.authenticate(username, password, err => {