Add support to create ECP assertion based on a token

A user should be able to exchange their token for an ECP wrapped
SAML assertion.

implements bp generate-saml-assertions

Change-Id: Ic9c20aebc5cd91650576ad050c09779df54f1d94

keystoneclient/tests/unit/v3/saml2_fixtures.py

@@ -170,8 +170,9 @@ DOMAINS = {
     }
 }
 
-TOKEN_BASED_SAML = """
-<?xml version='1.0' encoding='UTF-8'?>
+SAML_ENCODING = "<?xml version='1.0' encoding='UTF-8'?>"
+
+TOKEN_SAML_RESPONSE = """
 <ns2:Response Destination="http://beta.example.com/Shibboleth.sso/POST/ECP"
   ID="8c21de08d2f2435c9acf13e72c982846"
   IssueInstant="2015-03-25T14:43:21Z"
@@ -253,3 +254,28 @@ TOKEN_BASED_SAML = """
   </saml:Assertion>
 </ns2:Response>
 """
+
+TOKEN_BASED_SAML = ''.join([SAML_ENCODING, TOKEN_SAML_RESPONSE])
+
+ECP_ENVELOPE = """
+<ns0:Envelope
+  xmlns:ns0="http://schemas.xmlsoap.org/soap/envelope/"
+  xmlns:ns1="urn:oasis:names:tc:SAML:2.0:profiles:SSO:ecp"
+  xmlns:ns2="urn:oasis:names:tc:SAML:2.0:protocol"
+  xmlns:saml="urn:oasis:names:tc:SAML:2.0:assertion"
+  xmlns:xmldsig="http://www.w3.org/2000/09/xmldsig#"
+  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
+  <ns0:Header>
+    <ns1:RelayState
+      ns0:actor="http://schemas.xmlsoap.org/soap/actor/next"
+      ns0:mustUnderstand="1">
+        ss:mem:1ddfe8b0f58341a5a840d2e8717b0737
+      </ns1:RelayState>
+  </ns0:Header>
+  <ns0:Body>
+  {0}
+  </ns0:Body>
+</ns0:Envelope>
+""".format(TOKEN_SAML_RESPONSE)
+
+TOKEN_BASED_ECP = ''.join([SAML_ENCODING, ECP_ENVELOPE])

keystoneclient/tests/unit/v3/test_auth_saml2.py

@@ -631,6 +631,8 @@ class SAMLGenerationTests(utils.TestCase):
         self.manager = self.client.federation.saml
         self.SAML2_FULL_URL = ''.join([self.TEST_URL,
                                        saml_manager.SAML2_ENDPOINT])
+        self.ECP_FULL_URL = ''.join([self.TEST_URL,
+                                     saml_manager.ECP_ENDPOINT])
 
     def test_saml_create(self):
         """Test that a token can be exchanged for a SAML assertion."""
@@ -654,3 +656,26 @@ class SAMLGenerationTests(utils.TestCase):
         self.assertEqual(service_provider_id,
                          req_json['auth']['scope']['service_provider']['id'])
         self.assertRequestHeaderEqual('Content-Type', 'application/json')
+
+    def test_ecp_create(self):
+        """Test that a token can be exchanged for an ECP wrapped assertion."""
+
+        token_id = uuid.uuid4().hex
+        service_provider_id = uuid.uuid4().hex
+
+        # Mock returned text for '/auth/OS-FEDERATION/saml2/ecp
+        self.requests_mock.post(self.ECP_FULL_URL,
+                                text=saml2_fixtures.TOKEN_BASED_ECP)
+
+        text = self.manager.create_ecp_assertion(service_provider_id,
+                                                 token_id)
+
+        # Ensure returned text is correct
+        self.assertEqual(saml2_fixtures.TOKEN_BASED_ECP, text)
+
+        # Ensure request headers and body are correct
+        req_json = self.requests_mock.last_request.json()
+        self.assertEqual(token_id, req_json['auth']['identity']['token']['id'])
+        self.assertEqual(service_provider_id,
+                         req_json['auth']['scope']['service_provider']['id'])
+        self.assertRequestHeaderEqual('Content-Type', 'application/json')

keystoneclient/v3/contrib/federation/saml.py

@@ -14,6 +14,7 @@ from keystoneclient import base
 
 
 SAML2_ENDPOINT = '/auth/OS-FEDERATION/saml2'
+ECP_ENDPOINT = '/auth/OS-FEDERATION/saml2/ecp'
 
 
 class SamlManager(base.Manager):
@@ -34,6 +35,33 @@ class SamlManager(base.Manager):
         :rtype: string
         """
 
+        headers, body = self._create_common_request(service_provider, token_id)
+        resp, body = self.client.post(SAML2_ENDPOINT, json=body,
+                                      headers=headers)
+        return resp.text
+
+    def create_ecp_assertion(self, service_provider, token_id):
+        """Create an ECP wrapped SAML assertion from a token.
+
+        Equivalent Identity API call:
+        POST /auth/OS-FEDERATION/saml2/ecp
+
+        :param service_provider: Service Provider resource.
+        :type service_provider: string
+        :param token_id: Token to transform to SAML assertion.
+        :type token_id: string
+
+        :returns: SAML representation of token_id, wrapped in ECP envelope
+        :rtype: string
+        """
+
+        headers, body = self._create_common_request(service_provider, token_id)
+        resp, body = self.client.post(ECP_ENDPOINT, json=body,
+                                      headers=headers)
+        return resp.text
+
+    def _create_common_request(self, service_provider, token_id):
+        headers = {'Content-Type': 'application/json'}
         body = {
             'auth': {
                 'identity': {
@@ -50,7 +78,4 @@ class SamlManager(base.Manager):
             }
         }
 
-        headers = {'Content-Type': 'application/json'}
-        resp, body = self.client.post(SAML2_ENDPOINT, json=body,
-                                      headers=headers)
-        return resp.text
+        return (headers, body)