[feature] require authentication token for api

implements a global auth token for the app.

this token is written to .config/leap/authtoken, and passed to the
anchor part of the landing URI when opening the index resource by the
browser.

- Resolves: #8765

7 files changed, 73 insertions, 25 deletions

diff --git a/docs/core/index.rst b/docs/core/index.rst
index d03dd72..c7fb178 100644
--- a/docs/core/index.rst
+++ b/docs/core/index.rst
@@ -24,8 +24,31 @@ throught a REST API. In bitmaskd.cfg::
   [services]
   web = True
 
-API Authentication
-==================
+
+Global API Authentication
+=========================
+
+To avoid some kind of attacks, the Bitmask API is protected by a global
+authentication token.
+
+The JS API receives this value when the initial entrypoint is loaded for the
+first time, in the anchor part of the url.
+
+To authenticate any request to the API, the ``X-Bitmask-Auth`` header has to be
+added to it, set to the single value that is initialized during the bitmask
+deaemon startup::
+
+  curl -X POST http://localhost:7070/API/mail/status
+  unauthorized:bad auth token
+
+  curl -X POST http://localhost:7070/API/mail/status -H 'X-Bitmask-Auth: fae20706aa4f4f98ac0e67996787a370'
+  {"result": {"status": "on", "childrenStatus": {"smtp": {"status": "on", "error": null}, "imap": {"status": "on", "error": null}}, "error": null}, "error": null}
+
+This token can be found in ``.config/leap/authtoken``
+
+
+API Authentication (this section not implemented yet)
+======================================================
 
 By default, the resources in the API are protected by an authentication token.
 
diff --git a/src/leap/bitmask/core/service.py b/src/leap/bitmask/core/service.py
index 902bfa6..c06a534 100644
--- a/src/leap/bitmask/core/service.py
+++ b/src/leap/bitmask/core/service.py
@@ -18,6 +18,8 @@
 Bitmask-core Service.
 """
 import json
+import os
+import uuid
 try:
     import resource
 except ImportError:
@@ -62,6 +64,16 @@ class BitmaskBackend(configurable.ConfigurableService):
 
         configurable.ConfigurableService.__init__(self, basedir)
         self.core_commands = BackendCommands(self)
+
+        # The global token is used for authenticating some of the channels that
+        # expose the dispatcher. For the moment being, this is the REST API.
+        self.global_tokens = [uuid.uuid4().hex]
+        logger.info('Global token: {0}'.format(self.global_tokens[0]))
+        self._touch_token_file()
+
+        # These tokens are user-session tokens. Implemented and rolled back,
+        # unused for now. If we don't move forward with user-session tokens on
+        # top of the global app token, this should be removed.
         self.tokens = {}
 
         def enabled(service):
@@ -89,6 +101,12 @@ class BitmaskBackend(configurable.ConfigurableService):
         if enabled('websockets'):
             on_start(self._init_websockets)
 
+    def _touch_token_file(self):
+        path = os.path.join(self.basedir, 'authtoken')
+        with open(path, 'w') as f:
+            f.write(self.global_tokens[0])
+        os.chmod(path, 0600)
+
     def init_events(self):
         event_server.ensure_server()
 
diff --git a/src/leap/bitmask/core/web/_auth.py b/src/leap/bitmask/core/web/_auth.py
index 2747fae..aa6aeb9 100644
--- a/src/leap/bitmask/core/web/_auth.py
+++ b/src/leap/bitmask/core/web/_auth.py
@@ -6,6 +6,7 @@ from twisted.web.guard import HTTPAuthSessionWrapper, BasicCredentialFactory
 from twisted.web.resource import IResource
 
 
+# Deprecate if the user-session tokens are finally not used.
 class TokenCredentialFactory(BasicCredentialFactory):
     scheme = 'token'
 
@@ -37,11 +38,11 @@ class WhitelistHTTPAuthSessionWrapper(HTTPAuthSessionWrapper):
         return HTTPAuthSessionWrapper.render(self, request)
 
 
-def protectedResourceFactory(resource, session_tokens, whitelist):
+def protectedResourceFactory(resource, tokens, whitelist):
     realm = HttpPasswordRealm(resource)
-    checker = TokenDictChecker(session_tokens)
-    resource_portal = portal.Portal(realm, [checker])
+    checker = TokenDictChecker(tokens)
     credentialFactory = TokenCredentialFactory('localhost')
+    resource_portal = portal.Portal(realm, [checker])
     protected_resource = WhitelistHTTPAuthSessionWrapper(
         resource_portal, [credentialFactory],
         whitelist=whitelist)
diff --git a/src/leap/bitmask/core/web/api.py b/src/leap/bitmask/core/web/api.py
index d31afa5..01c65ba 100644
--- a/src/leap/bitmask/core/web/api.py
+++ b/src/leap/bitmask/core/web/api.py
@@ -11,11 +11,20 @@ class Api(Resource):
 
     isLeaf = True
 
-    def __init__(self, dispatcher):
+    def __init__(self, dispatcher, global_tokens):
         Resource.__init__(self)
         self.dispatcher = dispatcher
+        self.global_tokens = global_tokens
 
     def render_POST(self, request):
+        token = request.getHeader('x-bitmask-auth')
+        if not token:
+            request.setResponseCode(401)
+            return 'unauthorized: no app token'
+        elif token.strip() not in self.global_tokens:
+            request.setResponseCode(401)
+            return 'unauthorized: bad app token'
+
         command = request.uri.split('/')[2:]
         params = request.content.getvalue()
         if params:
diff --git a/src/leap/bitmask/core/web/service.py b/src/leap/bitmask/core/web/service.py
index c1d839e..2b8a734 100644
--- a/src/leap/bitmask/core/web/service.py
+++ b/src/leap/bitmask/core/web/service.py
@@ -61,11 +61,6 @@ class HTTPDispatcherService(service.Service):
     API_WHITELIST = (
         '/API/core/version',
         '/API/core/stats',
-        '/API/bonafide/user/create',
-        '/API/bonafide/user/authenticate',
-        '/API/bonafide/provider/list',
-        '/API/bonafide/provider/create',
-        '/API/bonafide/provider/read',
     )
 
     def __init__(self, core, port=7070, debug=False, onion=False):
@@ -76,7 +71,6 @@ class HTTPDispatcherService(service.Service):
         self.uri = ''
 
     def startService(self):
-        # TODO refactor this, too long----------------------------------------
         if HAS_WEB_UI:
             webdir = os.path.abspath(
                 pkg_resources.resource_filename('leap.bitmask_js', 'public'))
@@ -91,18 +85,16 @@ class HTTPDispatcherService(service.Service):
                 'ui', 'app', 'lib', 'bitmask.js')
             jsapi = File(os.path.abspath(jspath))
 
-        api = Api(CommandDispatcher(self._core))
-        # protected_api = protectedResourceFactory(
-        #    api, self._core.tokens, self.API_WHITELIST)
+        api = Api(CommandDispatcher(self._core), self._core.global_tokens)
 
         root = File(webdir)
+        root.putChild(u'API', api)
 
-        # FIXME -- switching off the protected api, due to
-        # https://0xacab.org/leap/bitmask-dev/issues/9
+        # XXX remove it we don't bring session tokens again
+        # protected_api = protectedResourceFactory(
+        # api, self._core.global_tokens, self.API_WHITELIST)
         # root.putChild(u'API', protected_api)
-        # -------------------------------------------------
 
-        root.putChild(u'API', api)
         if not HAS_WEB_UI:
             root.putChild('bitmask.js', jsapi)
 
@@ -110,7 +102,7 @@ class HTTPDispatcherService(service.Service):
         self.site = factory
 
         if self.onion and _has_txtorcon():
-                self._start_onion_service(factory)
+            self._start_onion_service(factory)
         else:
             interface = '127.0.0.1'
             endpoint = endpoints.TCP4ServerEndpoint(
diff --git a/src/leap/bitmask/gui/app.py b/src/leap/bitmask/gui/app.py
index ce9fc88..14025af 100644
--- a/src/leap/bitmask/gui/app.py
+++ b/src/leap/bitmask/gui/app.py
@@ -30,8 +30,8 @@ from functools import partial
 from multiprocessing import Process
 
 from leap.bitmask.core.launcher import run_bitmaskd, pid
-
 from leap.bitmask.gui import app_rc
+from leap.common.config import get_path_prefix
 
 
 if platform.system() == 'Windows':
@@ -51,7 +51,7 @@ else:
     from PyQt5.QtCore import QSize
 
 
-BITMASK_URI = 'http://localhost:7070'
+BITMASK_URI = 'http://localhost:7070/'
 
 IS_WIN = platform.system() == "Windows"
 DEBUG = os.environ.get("DEBUG", False)
@@ -100,7 +100,11 @@ class BrowserWindow(QDialog):
         self.closing = False
 
     def load_app(self):
-        self.view.load(QtCore.QUrl(BITMASK_URI))
+        path = os.path.join(get_path_prefix(), 'leap', 'authtoken')
+        global_token = open(path).read().strip()
+        anchored_uri = BITMASK_URI + 'index.html#' + global_token
+        print('[bitmask] opening Browser with {0}'.format(anchored_uri))
+        self.view.load(QtCore.QUrl(anchored_uri))
 
     def shutdown(self, *args):
         if self.closing:
diff --git a/tests/unit/core/test_web_api.py b/tests/unit/core/test_web_api.py
index 5b51869..10356f0 100644
--- a/tests/unit/core/test_web_api.py
+++ b/tests/unit/core/test_web_api.py
@@ -131,7 +131,7 @@ class RESTApiTests(unittest.TestCase):
 
     def setUp(self):
         dispatcher = dummyDispatcherFactory()
-        api = web.api.Api(dispatcher)
+        api = web.api.Api(dispatcher, ['aaa'])
         root = resource.Resource()
         root.putChild(b"API", api)
         plainSite = Site(root)
@@ -205,7 +205,8 @@ class RESTApiTests(unittest.TestCase):
         uri = networkString("http://127.0.0.1:%d/API/%s" % (
             self.plainPortno, path))
         return client.getPage(
-            uri, method=method, timeout=1, postdata=postdata)
+            uri, method=method, timeout=1, postdata=postdata,
+            headers={'X-Bitmask-Auth': 'aaa'})
 
     def assertCall(self, returned, expected):
         data = json.loads(returned)