implement two factor check during login

management/auth.py

@@ -2,12 +2,19 @@ import base64, os, os.path, hmac
 
 from flask import make_response
 
-import utils
+import utils, totp
 from mailconfig import get_mail_password, get_mail_user_privileges
+from mailconfig import get_two_factor_info, set_two_factor_last_used_token
 
 DEFAULT_KEY_PATH   = '/var/lib/mailinabox/api.key'
 DEFAULT_AUTH_REALM = 'Mail-in-a-Box Management Server'
 
+class MissingTokenError(ValueError):
+	pass
+
+class BadTokenError(ValueError):
+	pass
+
 class KeyAuthService:
 	"""Generate an API key for authenticating clients
 
@@ -76,8 +83,35 @@ class KeyAuthService:
 			return (None, ["admin"])
 		else:
 			# The user is trying to log in with a username and user-specific
-			# API key or password. Raises or returns privs.
+			# API key or password. Raises or returns privs and an indicator
-			return (username, self.get_user_credentials(username, password, env))
+			# whether the user is using their password or a user-specific API-key.
+			privs, is_user_key = self.get_user_credentials(username, password, env)
+
+			# If the user is using their API key to login, 2FA has been passed before
+			if is_user_key:
+				return (username, privs)
+
+			secret, last_token = get_two_factor_info(username, env)
+
+			# 2FA is not enabled, we can skip further checks
+			if secret == "" or secret == None:
+				return (username, privs)
+
+			# If 2FA is enabled, raise if:
+			# 1. no token is provided via `x-auth-token`
+			# 2. a previously supplied token is used (to counter replay attacks)
+			# 3. the token is invalid
+			# in that case, we need to raise and indicate to the client to supply a TOTP
+			token_header = request.headers.get('x-auth-token')
+			if token_header == None or token_header == "":
+				raise MissingTokenError("Two factor code missing (no x-auth-token supplied)")
+
+			# TODO: Should a token replay be handled as its own error?
+			if token_header == last_token or totp.validate(secret, token_header) != True:
+				raise BadTokenError("Two factor code incorrect")
+
+			set_two_factor_last_used_token(username, token_header, env)
+			return (username, privs)
 
 	def get_user_credentials(self, email, pw, env):
 		# Validate a user's credentials. On success returns a list of
@@ -88,11 +122,13 @@ class KeyAuthService:
 		if email == "" or pw == "":
 			raise ValueError("Enter an email address and password.")
 
+		is_user_key = False
+
 		# The password might be a user-specific API key. create_user_key raises
 		# a ValueError if the user does not exist.
 		if hmac.compare_digest(self.create_user_key(email, env), pw):
 			# OK.
-			pass
+			is_user_key = True
 		else:
 			# Get the hashed password of the user. Raise a ValueError if the
 			# email address does not correspond to a user.
@@ -119,7 +155,7 @@ class KeyAuthService:
 		if isinstance(privs, tuple): raise ValueError(privs[0])
 
 		# Return a list of privileges.
-		return privs
+		return (privs, is_user_key)
 
 	def create_user_key(self, email, env):
 		# Store an HMAC with the client. The hashed message of the HMAC will be the user's

management/daemon.py

@@ -40,14 +40,23 @@ def authorized_personnel_only(viewfunc):
 		error = None
 		try:
 			email, privs = auth_service.authenticate(request, env)
+		except auth.MissingTokenError as e:
+			privs = []
+			error = str(e)
+		except auth.BadTokenError as e:
+			# Write a line in the log recording the failed login
+			log_failed_login(request)
+
+			privs = []
+			error = str(e)
 		except ValueError as e:
+			# Write a line in the log recording the failed login
+			log_failed_login(request)
+
 			# Authentication failed.
 			privs = []
 			error = "Incorrect username or password"
 
-			# Write a line in the log recording the failed login
-			log_failed_login(request)
-
 		# Authorized to access an API view?
 		if "admin" in privs:
 			# Call view func.
@@ -119,6 +128,23 @@ def me():
 	# Is the caller authorized?
 	try:
 		email, privs = auth_service.authenticate(request, env)
+	except auth.MissingTokenError as e:
+		# Log the failed login
+		log_failed_login(request)
+
+		return json_response({
+			"status": "missing_token",
+			"reason": str(e),
+		})
+	except auth.BadTokenError as e:
+		# Log the failed login
+		log_failed_login(request)
+
+		return json_response({
+			"status": "bad_token",
+			"reason": str(e),
+		})
+
 	except ValueError as e:
 		# Log the failed login
 		log_failed_login(request)

management/templates/index.html

@@ -297,7 +297,7 @@ function ajax_with_indicator(options) {
 }
 
 var api_credentials = ["", ""];
-function api(url, method, data, callback, callback_error) {
+function api(url, method, data, callback, callback_error, headers) {
   // from http://www.webtoolkit.info/javascript-base64.html
   function base64encode(input) {
     _keyStr = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
@@ -335,7 +335,7 @@ function api(url, method, data, callback, callback_error) {
     method: method,
     cache: false,
     data: data,
-
+    headers: headers,
     // the custom DNS api sends raw POST/PUT bodies --- prevent URL-encoding
     processData: typeof data != "string",
     mimeType: typeof data == "string" ? "text/plain; charset=ascii" : null,

management/templates/login.html

@@ -1,4 +1,29 @@
-<h1 style="margin: 1em; text-align: center">{{hostname}}</h1>
+<style>
+  .title {
+    margin: 1em;
+    text-align: center;
+  }
+
+  .subtitle {
+    margin: 2em;
+    text-align: center;
+  }
+
+  .login {
+    margin: 0 auto;
+    max-width: 32em;
+  }
+
+  .login #loginOtp {
+    display: none;
+  }
+
+  #loginForm.twofactor #loginOtp {
+    display: block
+  }
+</style>
+
+<h1 class="title">{{hostname}}</h1>
 
 {% if no_users_exist or no_admins_exist %}
 <div class="row">
@@ -20,10 +45,10 @@ sudo tools/mail.py user make-admin me@{{hostname}}</pre>
 </div>
 {% endif %}
 
-<p style="margin: 2em; text-align: center;">Log in here for your Mail-in-a-Box control panel.</p>
+<p class="subtitle">Log in here for your Mail-in-a-Box control panel.</p>
 
-<div style="margin: 0 auto; max-width: 32em;">
+<div class="login">
-  <form class="form-horizontal" role="form" onsubmit="do_login(); return false;" method="get">
+  <form id="loginForm" class="form-horizontal" role="form" onsubmit="do_login(); return false;" method="get">
     <div class="form-group">
       <label for="inputEmail3" class="col-sm-3 control-label">Email</label>
       <div class="col-sm-9">
@@ -45,6 +70,12 @@ sudo tools/mail.py user make-admin me@{{hostname}}</pre>
         </div>
       </div>
     </div>
+    <div class="form-group" id="loginOtp">
+        <label for="loginOtpInput" class="col-sm-3 control-label">Two Factor Code</label>
+        <div class="col-sm-9">
+            <input type="text" class="form-control" id="loginOtpInput" placeholder="123456">
+        </div>
+    </div>
     <div class="form-group">
       <div class="col-sm-offset-3 col-sm-9">
         <button type="submit" class="btn btn-default">Sign in</button>
@@ -53,7 +84,6 @@ sudo tools/mail.py user make-admin me@{{hostname}}</pre>
   </form>
 </div>
 
-
 <script>
 function do_login() {
   if ($('#loginEmail').val() == "") {
@@ -79,13 +109,17 @@ function do_login() {
   function(response) {
     // This API call always succeeds. It returns a JSON object indicating
     // whether the request was authenticated or not.
-    if (response.status != "ok") {
+    if (response.status != 'ok') {
+      if (response.status === 'missing_token' && !$('#loginForm').hasClass('twofactor')) {
+        $('#loginForm').addClass('twofactor');
+      } else {
+        $('#loginForm').removeClass('twofactor');
         // Show why the login failed.
         show_modal_error("Login Failed", response.reason)
 
         // Reset any saved credentials.
         do_logout();
-
+      }
     } else if (!("api_key" in response)) {
       // Login succeeded but user might not be authorized!
       show_modal_error("Login Failed", "You are not an administrator on this system.")
@@ -102,6 +136,8 @@ function do_login() {
       // Try to wipe the username/password information.
       $('#loginEmail').val('');
       $('#loginPassword').val('');
+      $('#loginOtpInput').val('');
+      $('#loginForm').removeClass('twofactor');
 
       // Remember the credentials.
       if (typeof localStorage != 'undefined' && typeof sessionStorage != 'undefined') {
@@ -119,7 +155,11 @@ function do_login() {
       // which confuses the loading indicator.
       setTimeout(function() { show_panel(!switch_back_to_panel || switch_back_to_panel == "login" ? 'system_status' : switch_back_to_panel) }, 300);
     }
-  })
+  },
+  undefined,
+  {
+    'x-auth-token': $('#loginOtpInput').val()
+  });
 }
 
 function do_logout() {
@@ -132,6 +172,8 @@ function do_logout() {
 }
 
 function show_login() {
+  $('#loginForm').removeClass('twofactor');
+  $('#loginOtpInput').val('');
   $('#loginEmail,#loginPassword').each(function() {
     var input = $(this);
     if (!$.trim(input.val())) {