2 files changed, 56 insertions, 11 deletions

diff --git a/synapse/rest/client/v1/login.py b/synapse/rest/client/v1/login.py
index 4efb679a04..a31d277935 100644
--- a/synapse/rest/client/v1/login.py
+++ b/synapse/rest/client/v1/login.py
@@ -86,6 +86,7 @@ class LoginRestServlet(RestServlet):
         self.jwt_enabled = hs.config.jwt_enabled
         self.jwt_secret = hs.config.jwt_secret
         self.jwt_algorithm = hs.config.jwt_algorithm
+        self.saml2_enabled = hs.config.saml2_enabled
         self.cas_enabled = hs.config.cas_enabled
         self.auth_handler = self.hs.get_auth_handler()
         self.registration_handler = hs.get_registration_handler()
@@ -97,6 +98,9 @@ class LoginRestServlet(RestServlet):
         flows = []
         if self.jwt_enabled:
             flows.append({"type": LoginRestServlet.JWT_TYPE})
+        if self.saml2_enabled:
+            flows.append({"type": LoginRestServlet.SSO_TYPE})
+            flows.append({"type": LoginRestServlet.TOKEN_TYPE})
         if self.cas_enabled:
             flows.append({"type": LoginRestServlet.SSO_TYPE})
 
@@ -354,27 +358,49 @@ class LoginRestServlet(RestServlet):
         defer.returnValue(result)
 
 
-class CasRedirectServlet(RestServlet):
+class BaseSsoRedirectServlet(RestServlet):
+    """Common base class for /login/sso/redirect impls"""
+
     PATTERNS = client_patterns("/login/(cas|sso)/redirect", v1=True)
 
+    def on_GET(self, request):
+        args = request.args
+        if b"redirectUrl" not in args:
+            return 400, "Redirect URL not specified for SSO auth"
+        client_redirect_url = args[b"redirectUrl"][0]
+        sso_url = self.get_sso_url(client_redirect_url)
+        request.redirect(sso_url)
+        finish_request(request)
+
+    def get_sso_url(self, client_redirect_url):
+        """Get the URL to redirect to, to perform SSO auth
+
+        Args:
+            client_redirect_url (bytes): the URL that we should redirect the
+                client to when everything is done
+
+        Returns:
+            bytes: URL to redirect to
+        """
+        # to be implemented by subclasses
+        raise NotImplementedError()
+
+
+class CasRedirectServlet(BaseSsoRedirectServlet):
     def __init__(self, hs):
         super(CasRedirectServlet, self).__init__()
         self.cas_server_url = hs.config.cas_server_url.encode("ascii")
         self.cas_service_url = hs.config.cas_service_url.encode("ascii")
 
-    def on_GET(self, request):
-        args = request.args
-        if b"redirectUrl" not in args:
-            return (400, "Redirect URL not specified for CAS auth")
+    def get_sso_url(self, client_redirect_url):
         client_redirect_url_param = urllib.parse.urlencode(
-            {b"redirectUrl": args[b"redirectUrl"][0]}
+            {b"redirectUrl": client_redirect_url}
         ).encode("ascii")
         hs_redirect_url = self.cas_service_url + b"/_matrix/client/r0/login/cas/ticket"
         service_param = urllib.parse.urlencode(
             {b"service": b"%s?%s" % (hs_redirect_url, client_redirect_url_param)}
         ).encode("ascii")
-        request.redirect(b"%s/login?%s" % (self.cas_server_url, service_param))
-        finish_request(request)
+        return b"%s/login?%s" % (self.cas_server_url, service_param)
 
 
 class CasTicketServlet(RestServlet):
@@ -457,6 +483,25 @@ class CasTicketServlet(RestServlet):
         return user, attributes
 
 
+class SAMLRedirectServlet(BaseSsoRedirectServlet):
+    PATTERNS = client_patterns("/login/sso/redirect", v1=True)
+
+    def __init__(self, hs):
+        self._saml_client = hs.get_saml_client()
+
+    def get_sso_url(self, client_redirect_url):
+        reqid, info = self._saml_client.prepare_for_authenticate(
+            relay_state=client_redirect_url
+        )
+
+        for key, value in info["headers"]:
+            if key == "Location":
+                return value
+
+        # this shouldn't happen!
+        raise Exception("prepare_for_authenticate didn't return a Location header")
+
+
 class SSOAuthHandler(object):
     """
     Utility class for Resources and Servlets which handle the response from a SSO
@@ -532,3 +577,5 @@ def register_servlets(hs, http_server):
     if hs.config.cas_enabled:
         CasRedirectServlet(hs).register(http_server)
         CasTicketServlet(hs).register(http_server)
+    elif hs.config.saml2_enabled:
+        SAMLRedirectServlet(hs).register(http_server)
diff --git a/synapse/rest/saml2/response_resource.py b/synapse/rest/saml2/response_resource.py
index ab14b70675..9ec56d6adb 100644
--- a/synapse/rest/saml2/response_resource.py
+++ b/synapse/rest/saml2/response_resource.py
@@ -16,7 +16,6 @@
 import logging
 
 import saml2
-from saml2.client import Saml2Client
 
 from twisted.web.resource import Resource
 from twisted.web.server import NOT_DONE_YET
@@ -36,8 +35,7 @@ class SAML2ResponseResource(Resource):
 
     def __init__(self, hs):
         Resource.__init__(self)
-
-        self._saml_client = Saml2Client(hs.config.saml2_sp_config)
+        self._saml_client = hs.get_saml_client()
         self._sso_auth_handler = SSOAuthHandler(hs)
 
     def render_POST(self, request):