Initial Commit

lib/cherrypy/lib/auth.py

@@ -0,0 +1,97 @@
+import cherrypy
+from cherrypy.lib import httpauth
+
+
+def check_auth(users, encrypt=None, realm=None):
+    """If an authorization header contains credentials, return True or False.
+    """
+    request = cherrypy.serving.request
+    if 'authorization' in request.headers:
+        # make sure the provided credentials are correctly set
+        ah = httpauth.parseAuthorization(request.headers['authorization'])
+        if ah is None:
+            raise cherrypy.HTTPError(400, 'Bad Request')
+
+        if not encrypt:
+            encrypt = httpauth.DIGEST_AUTH_ENCODERS[httpauth.MD5]
+
+        if hasattr(users, '__call__'):
+            try:
+                # backward compatibility
+                users = users()  # expect it to return a dictionary
+
+                if not isinstance(users, dict):
+                    raise ValueError(
+                        "Authentication users must be a dictionary")
+
+                # fetch the user password
+                password = users.get(ah["username"], None)
+            except TypeError:
+                # returns a password (encrypted or clear text)
+                password = users(ah["username"])
+        else:
+            if not isinstance(users, dict):
+                raise ValueError("Authentication users must be a dictionary")
+
+            # fetch the user password
+            password = users.get(ah["username"], None)
+
+        # validate the authorization by re-computing it here
+        # and compare it with what the user-agent provided
+        if httpauth.checkResponse(ah, password, method=request.method,
+                                  encrypt=encrypt, realm=realm):
+            request.login = ah["username"]
+            return True
+
+        request.login = False
+    return False
+
+
+def basic_auth(realm, users, encrypt=None, debug=False):
+    """If auth fails, raise 401 with a basic authentication header.
+
+    realm
+        A string containing the authentication realm.
+
+    users
+        A dict of the form: {username: password} or a callable returning
+        a dict.
+
+    encrypt
+        callable used to encrypt the password returned from the user-agent.
+        if None it defaults to a md5 encryption.
+
+    """
+    if check_auth(users, encrypt):
+        if debug:
+            cherrypy.log('Auth successful', 'TOOLS.BASIC_AUTH')
+        return
+
+    # inform the user-agent this path is protected
+    cherrypy.serving.response.headers[
+        'www-authenticate'] = httpauth.basicAuth(realm)
+
+    raise cherrypy.HTTPError(
+        401, "You are not authorized to access that resource")
+
+
+def digest_auth(realm, users, debug=False):
+    """If auth fails, raise 401 with a digest authentication header.
+
+    realm
+        A string containing the authentication realm.
+    users
+        A dict of the form: {username: password} or a callable returning
+        a dict.
+    """
+    if check_auth(users, realm=realm):
+        if debug:
+            cherrypy.log('Auth successful', 'TOOLS.DIGEST_AUTH')
+        return
+
+    # inform the user-agent this path is protected
+    cherrypy.serving.response.headers[
+        'www-authenticate'] = httpauth.digestAuth(realm)
+
+    raise cherrypy.HTTPError(
+        401, "You are not authorized to access that resource")