1 files changed, 150 insertions, 0 deletions
diff --git a/src/pixelated/resources/auth.py b/src/pixelated/resources/auth.py
new file mode 100644
index 00000000..3497f325
--- /dev/null
+++ b/src/pixelated/resources/auth.py
@@ -0,0 +1,150 @@
+#
+# Copyright (c) 2016 ThoughtWorks, Inc.
+#
+# Pixelated is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# Pixelated is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with Pixelated. If not, see <http://www.gnu.org/licenses/>.
+
+import logging
+
+from leap.auth import SRPAuth
+from leap.exceptions import SRPAuthenticationError
+from twisted.cred.checkers import ANONYMOUS
+from twisted.cred.credentials import ICredentials
+from twisted.cred.error import UnauthorizedLogin
+from twisted.internet import defer, threads
+from twisted.web._auth.wrapper import UnauthorizedResource
+from twisted.web.error import UnsupportedMethod
+from zope.interface import implements, implementer, Attribute
+from twisted.cred import portal, checkers, credentials
+from twisted.web import util
+from twisted.cred import error
+from twisted.web.resource import IResource, ErrorPage
+
+from pixelated.config.leap import authenticate_user
+from pixelated.resources import IPixelatedSession
+
+
+log = logging.getLogger(__name__)
+
+
+@implementer(checkers.ICredentialsChecker)
+class LeapPasswordChecker(object):
+    credentialInterfaces = (
+        credentials.IUsernamePassword,
+    )
+
+    def __init__(self, leap_provider):
+        self._leap_provider = leap_provider
+
+    def requestAvatarId(self, credentials):
+        def _validate_credentials():
+            try:
+                srp_auth = SRPAuth(self._leap_provider.api_uri,
+                                   self._leap_provider.local_ca_crt)
+                return srp_auth.authenticate(credentials.username, credentials.password)
+            except SRPAuthenticationError:
+                raise UnauthorizedLogin()
+
+        def _get_leap_session(srp_auth):
+            return authenticate_user(self._leap_provider, credentials.username, credentials.password, auth=srp_auth)
+
+        d = threads.deferToThread(_validate_credentials)
+        d.addCallback(_get_leap_session)
+        return d
+
+
+class ISessionCredential(ICredentials):
+
+    request = Attribute('the current request')
+
+
+@implementer(ISessionCredential)
+class SessionCredential(object):
+
+    def __init__(self, request):
+        self.request = request
+
+
+@implementer(checkers.ICredentialsChecker)
+class SessionChecker(object):
+    credentialInterfaces = (ISessionCredential,)
+
+    def __init__(self, services_factory):
+        self._services_factory = services_factory
+
+    def requestAvatarId(self, credentials):
+        session = self.get_session(credentials.request)
+        if session.is_logged_in() and self._services_factory.is_logged_in(session.user_uuid):
+            return defer.succeed(session.user_uuid)
+        return defer.succeed(ANONYMOUS)
+
+    def get_session(self, request):
+        return IPixelatedSession(request.getSession())
+
+
+class PixelatedRealm(object):
+    implements(portal.IRealm)
+
+    def __init__(self, root_resource, anonymous_resource):
+        self._root_resource = root_resource
+        self._anonymous_resource = anonymous_resource
+
+    def requestAvatar(self, avatarId, mind, *interfaces):
+        if IResource in interfaces:
+            return IResource, avatarId, lambda: None
+        raise NotImplementedError()
+
+
+@implementer(IResource)
+class PixelatedAuthSessionWrapper(object):
+
+    isLeaf = False
+
+    def __init__(self, portal, root_resource, anonymous_resource, credentialFactories):
+        self._portal = portal
+        self._credentialFactories = credentialFactories
+        self._root_resource = root_resource
+        self._anonymous_resource = anonymous_resource
+
+    def render(self, request):
+        raise UnsupportedMethod(())
+
+    def getChildWithDefault(self, path, request):
+        request.postpath.insert(0, request.prepath.pop())
+        return self._authorizedResource(request)
+
+    def _authorizedResource(self, request):
+        creds = SessionCredential(request)
+        return util.DeferredResource(self._login(creds))
+
+    def _login(self, credentials):
+        d = self._portal.login(credentials, None, IResource)
+        d.addCallbacks(self._loginSucceeded, self._loginFailed)
+        return d
+
+    def _loginSucceeded(self, args):
+        interface, avatar, logout = args
+        if avatar == checkers.ANONYMOUS:
+            return self._anonymous_resource
+        else:
+            return self._root_resource
+
+    def _loginFailed(self, result):
+        if result.check(error.Unauthorized, error.LoginFailed):
+            return UnauthorizedResource(self._credentialFactories)
+        else:
+            log.err(
+                result,
+                "HTTPAuthSessionWrapper.getChildWithDefault encountered "
+                "unexpected error")
+            return ErrorPage(500, None, None)