Implement an OpenID identity provider.

2 files changed, 113 insertions, 1 deletions

diff --git a/src/mulk/benki/id.clj b/src/mulk/benki/id.clj
new file mode 100644
index 0000000..1442903
--- /dev/null
+++ b/src/mulk/benki/id.clj
@@ -0,0 +1,112 @@
+(ns mulk.benki.id
+  (:refer-clojure)
+  (:use [clojure         core repl pprint]
+        [hiccup core     page-helpers]
+        [mulk.benki      config util db]
+        [clojure.core.match
+         :only [match]]
+        [noir            core]
+        [clojure.java.jdbc :only [transaction do-commands]])
+  (:require [noir.session      :as session]
+            [noir.response     :as response]
+            [noir.request      :as request]
+            [clojure.java.jdbc :as sql]
+            [com.twinql.clojure.http :as http])
+  (:import [org.openid4java.server ServerManager]
+           [org.openid4java.message ParameterList AuthRequest DirectError]))
+
+
+(defonce manager
+  (doto (ServerManager.)
+    (.setOPEndpointUrl (str (:base-uri @benki-config) "/openid"))))
+
+(def profile-base-uri (str (:base-uri @benki-config) "/id/"))
+
+(defn user-owns-nickname? [user nickname]
+  (with-dbt
+    (sql/with-query-results results
+      ["SELECT 't' FROM user_nicknames WHERE nickname = ? AND \"user\" = ?"
+       nickname *user*]
+      (doall (seq results)))))
+
+(defn fail-authentication []
+  {:status 403, :type "text/plain", :body "Not authorized."})
+
+(defn nickname-from-profile-uri [uri]
+  (let [base-uri (.substring uri 0 (.length profile-base-uri))
+        nickname (.substring uri (.length profile-base-uri))]
+    (if (= base-uri profile-base-uri)
+      nickname
+      nil)))
+
+(defn format-openid-response [s]
+  {:status 200, :type "text/plain", :body s})
+
+(defn verify-openid [paramlist]
+  (let [auth-request (AuthRequest/createAuthRequest paramlist (.getRealmVerifier manager))
+        claimed-id   (or (.getClaimed auth-request)
+                         (get (:query-params (request/ring-request)) "openid.identity"))
+        nickname     (nickname-from-profile-uri claimed-id)
+        okay?        (and *user* (user-owns-nickname? *user* nickname))
+        response     (.authResponse manager paramlist nil claimed-id (boolean okay?) false)]
+    (if (isa? (class response) DirectError)
+      (fail-authentication)
+      (do
+        (.sign manager response)
+        (redirect (.getDestinationUrl response true))))))
+
+(defn process-openid-request []
+  (let [query     (:params (request/ring-request))
+        paramlist (ParameterList. query)
+        mode      (query "openid.mode")]
+    (match [mode]
+      ["associate"]
+        (format-openid-response
+         (.keyValueFormEncoding (.associationRequest manager paramlist)))
+      ["check_authentication"]
+        (format-openid-response
+         (.keyValueFormEncoding (.verify manager paramlist)))
+      ["checkid_setup"]
+        (with-auth
+          (verify-openid paramlist))
+      ["checkid_immediate"]
+        (verify-openid paramlist)
+      [x]
+        {:status 200, :headers {"Content-Type" "text/plain; charset=utf-8"}, :body (str "Whaaaat?  What is “" x "” supposed to mean??   This is what you sent:" (request/ring-request)
+                                                                                        )})))
+
+(def profile-page {})
+
+(defn show-profile-page []
+  (layout profile-page "A Profile Page"
+    [:body
+     [:p "This is a profile page."]]))
+
+(defn render-xrds [nickname]
+  {:status 200
+   :headers {"Content-Type" "application/xrds+xml; charset=UTF-8"}
+   :body
+   (clojure.string/replace
+    "<?xml version=\"1.0\" encoding=\"UTF-8\"?>
+     <xrds:XRDS xmlns:xrds=\"xri://$xrds\" xmlns=\"xri://$xrd*($v*2.0)\">
+       <XRD>
+         <Service>
+           <Type>http://openid.net/signon/1.0</Type>
+           <URI>{base-uri}/openid/api</URI>
+         </Service>
+       </XRD>
+     </xrds:XRDS>"
+    "{base-uri}"
+    (:base-uri @benki-config))})
+
+(defpage [:get  "/openid/api"] {}
+  (process-openid-request))
+
+(defpage [:post "/openid/api"] {}
+  (process-openid-request))
+
+(defpage [:get  "/id/:nickname"] {nickname :nickname}
+  (if (re-find #"application/xrds\+xml"
+               (get-in (request/ring-request) [:headers "accept"]))
+    (render-xrds nickname)
+    (show-profile-page)))
diff --git a/src/mulk/benki/main.clj b/src/mulk/benki/main.clj
index 7ec01ec..bdecdc1 100644
--- a/src/mulk/benki/main.clj
+++ b/src/mulk/benki/main.clj
@@ -5,7 +5,7 @@
         [hiccup core     page-helpers]
         [mulk.benki      util config db])
   (:require [noir server options]
-            [mulk.benki wiki auth book_marx]
+            [mulk.benki wiki auth book_marx id]
             [ring.middleware.file]
             [noir.session      :as session]
             [noir.request      :as request]