Fixing key error in Keystone authentication
[osm/NBI.git] / osm_nbi / auth.py
index 4bc4628..18986a3 100644 (file)
@@ -1,17 +1,23 @@
 # -*- coding: utf-8 -*-
 
 # -*- coding: utf-8 -*-
 
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
+# Copyright 2018 Whitestack, LLC
+# Copyright 2018 Telefonica S.A.
 #
 #
-#    http://www.apache.org/licenses/LICENSE-2.0
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
 #
 # Unless required by applicable law or agreed to in writing, software
 #
 # Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
-# implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+#
+# For those usages not covered by the Apache License, Version 2.0 please
+# contact: esousa@whitestack.com or alfonso.tiernosepulveda@telefonica.com
+##
 
 
 """
 
 
 """
@@ -19,12 +25,14 @@ Authenticator is responsible for authenticating the users,
 create the tokens unscoped and scoped, retrieve the role
 list inside the projects that they are inserted
 """
 create the tokens unscoped and scoped, retrieve the role
 list inside the projects that they are inserted
 """
+from os import path
 
 __author__ = "Eduardo Sousa <esousa@whitestack.com>; Alfonso Tierno <alfonso.tiernosepulveda@telefonica.com>"
 __date__ = "$27-jul-2018 23:59:59$"
 
 import cherrypy
 import logging
 
 __author__ = "Eduardo Sousa <esousa@whitestack.com>; Alfonso Tierno <alfonso.tiernosepulveda@telefonica.com>"
 __date__ = "$27-jul-2018 23:59:59$"
 
 import cherrypy
 import logging
+import yaml
 from base64 import standard_b64decode
 from copy import deepcopy
 from functools import reduce
 from base64 import standard_b64decode
 from copy import deepcopy
 from functools import reduce
@@ -32,6 +40,7 @@ from hashlib import sha256
 from http import HTTPStatus
 from random import choice as random_choice
 from time import time
 from http import HTTPStatus
 from random import choice as random_choice
 from time import time
+from uuid import uuid4
 
 from authconn import AuthException
 from authconn_keystone import AuthconnKeystone
 
 from authconn import AuthException
 from authconn_keystone import AuthconnKeystone
@@ -48,7 +57,7 @@ class Authenticator:
     RBAC model to manage permissions on operations.
     """
 
     RBAC model to manage permissions on operations.
     """
 
-    periodin_db_pruning = 60*30  # for the internal backend only. every 30 minutes expired tokens will be pruned
+    periodin_db_pruning = 60 * 30  # for the internal backend only. every 30 minutes expired tokens will be pruned
 
     def __init__(self):
         """
 
     def __init__(self):
         """
@@ -60,7 +69,10 @@ class Authenticator:
         self.db = None
         self.tokens_cache = dict()
         self.next_db_prune_time = 0  # time when next cleaning of expired tokens must be done
         self.db = None
         self.tokens_cache = dict()
         self.next_db_prune_time = 0  # time when next cleaning of expired tokens must be done
-
+        self.resources_to_operations_file = None
+        self.roles_to_operations_file = None
+        self.resources_to_operations_mapping = {}
+        self.operation_to_allowed_roles = {}
         self.logger = logging.getLogger("nbi.authenticator")
 
     def start(self, config):
         self.logger = logging.getLogger("nbi.authenticator")
 
     def start(self, config):
@@ -92,6 +104,28 @@ class Authenticator:
                 else:
                     raise AuthException("Unknown authentication backend: {}"
                                         .format(config["authentication"]["backend"]))
                 else:
                     raise AuthException("Unknown authentication backend: {}"
                                         .format(config["authentication"]["backend"]))
+            if not self.resources_to_operations_file:
+                if "resources_to_operations" in config["rbac"]:
+                    self.resources_to_operations_file = config["rbac"]["resources_to_operations"]
+                else:
+                    for config_file in (__file__[:__file__.rfind("auth.py")] + "resources_to_operations.yml",
+                                        "./resources_to_operations.yml"):
+                        if path.isfile(config_file):
+                            self.resources_to_operations_file = config_file
+                            break
+                    if not self.resources_to_operations_file:
+                        raise AuthException("Invalid permission configuration: resources_to_operations file missing")
+            if not self.roles_to_operations_file:
+                if "roles_to_operations" in config["rbac"]:
+                    self.roles_to_operations_file = config["rbac"]["roles_to_operations"]
+                else:
+                    for config_file in (__file__[:__file__.rfind("auth.py")] + "roles_to_operations.yml",
+                                        "./roles_to_operations.yml"):
+                        if path.isfile(config_file):
+                            self.roles_to_operations_file = config_file
+                            break
+                    if not self.roles_to_operations_file:
+                        raise AuthException("Invalid permission configuration: roles_to_operations file missing")
         except Exception as e:
             raise AuthException(str(e))
 
         except Exception as e:
             raise AuthException(str(e))
 
@@ -102,15 +136,125 @@ class Authenticator:
         except DbException as e:
             raise AuthException(str(e), http_code=e.http_code)
 
         except DbException as e:
             raise AuthException(str(e), http_code=e.http_code)
 
-    def init_db(self, target_version='1.1'):
+    def init_db(self, target_version='1.0'):
         """
         """
-        Check if the database has been initialized, with at least one user. If not, create an adthe required tables
+        Check if the database has been initialized, with at least one user. If not, create the required tables
         and insert the predefined mappings between roles and permissions.
 
         :param target_version: schema version that should be present in the database.
         :return: None if OK, exception if error or version is different.
         """
         and insert the predefined mappings between roles and permissions.
 
         :param target_version: schema version that should be present in the database.
         :return: None if OK, exception if error or version is different.
         """
-        pass
+        # Always reads operation to resource mapping from file (this is static, no need to store it in MongoDB)
+        # Operations encoding: "<METHOD> <URL>"
+        # Note: it is faster to rewrite the value than to check if it is already there or not
+        operations = []
+        with open(self.resources_to_operations_file, "r") as stream:
+            resources_to_operations_yaml = yaml.load(stream)
+
+        for resource, operation in resources_to_operations_yaml["resources_to_operations"].items():
+            operation_key = operation.replace(".", ":")
+            if operation_key not in operations:
+                operations.append(operation_key)
+            self.resources_to_operations_mapping[resource] = operation_key
+
+        records = self.db.get_list("roles_operations")
+
+        # Loading permissions to MongoDB. If there are permissions already in MongoDB, do nothing.
+        if len(records) == 0:
+            with open(self.roles_to_operations_file, "r") as stream:
+                roles_to_operations_yaml = yaml.load(stream)
+
+            roles = []
+            for role_with_operations in roles_to_operations_yaml["roles_to_operations"]:
+                # Verifying if role already exists. If it does, send warning to log and ignore it.
+                if role_with_operations["role"] not in roles:
+                    roles.append(role_with_operations["role"])
+                else:
+                    self.logger.warning("Duplicated role with name: {0}. Role definition is ignored."
+                                        .format(role_with_operations["role"]))
+                    continue
+
+                role_ops = {}
+                root = None
+
+                if not role_with_operations["operations"]:
+                    continue
+
+                for operation, is_allowed in role_with_operations["operations"].items():
+                    if not isinstance(is_allowed, bool):
+                        continue
+
+                    if operation == ".":
+                        root = is_allowed
+                        continue
+
+                    if len(operation) != 1 and operation[-1] == ".":
+                        self.logger.warning("Invalid operation {0} terminated in '.'. "
+                                            "Operation will be discarded"
+                                            .format(operation))
+                        continue
+
+                    operation_key = operation.replace(".", ":")
+                    if operation_key not in role_ops.keys():
+                        role_ops[operation_key] = is_allowed
+                    else:
+                        self.logger.info("In role {0}, the operation {1} with the value {2} was discarded due to "
+                                         "repetition.".format(role_with_operations["role"], operation, is_allowed))
+
+                if not root:
+                    root = False
+                    self.logger.info("Root for role {0} not defined. Default value 'False' applied."
+                                     .format(role_with_operations["role"]))
+
+                now = time()
+                operation_to_roles_item = {
+                    "_id": str(uuid4()),
+                    "_admin": {
+                        "created": now,
+                        "modified": now,
+                    },
+                    "role": role_with_operations["role"],
+                    "root": root
+                }
+
+                for operation, value in role_ops.items():
+                    operation_to_roles_item[operation] = value
+
+                self.db.create("roles_operations", operation_to_roles_item)
+
+        permissions = {oper: [] for oper in operations}
+        records = self.db.get_list("roles_operations")
+
+        ignore_fields = ["_id", "_admin", "role", "root"]
+        roles = []
+        for record in records:
+
+            roles.append(record["role"])
+            record_permissions = {oper: record["root"] for oper in operations}
+            operations_joined = [(oper, value) for oper, value in record.items() if oper not in ignore_fields]
+            operations_joined.sort(key=lambda x: x[0].count(":"))
+
+            for oper in operations_joined:
+                match = list(filter(lambda x: x.find(oper[0]) == 0, record_permissions.keys()))
+
+                for m in match:
+                    record_permissions[m] = oper[1]
+
+            allowed_operations = [k for k, v in record_permissions.items() if v is True]
+
+            for allowed_op in allowed_operations:
+                permissions[allowed_op].append(record["role"])
+
+        for oper, role_list in permissions.items():
+            self.operation_to_allowed_roles[oper] = role_list
+
+        if self.config["authentication"]["backend"] != "internal":
+            for role in roles:
+                if role == "anonymous":
+                    continue
+                self.backend.create_role(role)
+
+            self.backend.assign_role_to_user("admin", "admin", "system_admin")
 
     def authorize(self):
         token = None
 
     def authorize(self):
         token = None
@@ -145,10 +289,15 @@ class Authenticator:
             if self.config["authentication"]["backend"] == "internal":
                 return self._internal_authorize(token)
             else:
             if self.config["authentication"]["backend"] == "internal":
                 return self._internal_authorize(token)
             else:
+                if not token:
+                    raise AuthException("Needed a token or Authorization http header",
+                                        http_code=HTTPStatus.UNAUTHORIZED)
                 try:
                     self.backend.validate_token(token)
                 try:
                     self.backend.validate_token(token)
+                    self.check_permissions(self.tokens_cache[token], cherrypy.request.path_info,
+                                           cherrypy.request.method)
                     # TODO: check if this can be avoided. Backend may provide enough information
                     # TODO: check if this can be avoided. Backend may provide enough information
-                    return self.tokens_cache[token]
+                    return deepcopy(self.tokens_cache[token])
                 except AuthException:
                     self.del_token(token)
                     raise
                 except AuthException:
                     self.del_token(token)
                     raise
@@ -180,6 +329,9 @@ class Authenticator:
             else:
                 project_id = projects[0]
 
             else:
                 project_id = projects[0]
 
+            if not session:
+                token, projects = self.backend.authenticate_with_token(token, project_id)
+
             if project_id == "admin":
                 session_admin = True
             else:
             if project_id == "admin":
                 session_admin = True
             else:
@@ -239,6 +391,79 @@ class Authenticator:
             except KeyError:
                 raise AuthException("Token '{}' not found".format(token), http_code=HTTPStatus.NOT_FOUND)
 
             except KeyError:
                 raise AuthException("Token '{}' not found".format(token), http_code=HTTPStatus.NOT_FOUND)
 
+    def check_permissions(self, session, url, method):
+        self.logger.info("Session: {}".format(session))
+        self.logger.info("URL: {}".format(url))
+        self.logger.info("Method: {}".format(method))
+
+        key, parameters = self._normalize_url(url, method)
+
+        # TODO: Check if parameters might be useful for the decision
+
+        operation = self.resources_to_operations_mapping[key]
+        roles_required = self.operation_to_allowed_roles[operation]
+        roles_allowed = self.backend.get_role_list(session["id"])
+
+        if "anonymous" in roles_required:
+            return
+
+        for role in roles_allowed:
+            if role in roles_required:
+                return
+
+        raise AuthException("Access denied: lack of permissions.")
+
+    def _normalize_url(self, url, method):
+        # Removing query strings
+        normalized_url = url if '?' not in url else url[:url.find("?")]
+        normalized_url_splitted = normalized_url.split("/")
+        parameters = {}
+
+        filtered_keys = [key for key in self.resources_to_operations_mapping.keys()
+                         if method in key.split()[0]]
+
+        for idx, path_part in enumerate(normalized_url_splitted):
+            tmp_keys = []
+            for tmp_key in filtered_keys:
+                splitted = tmp_key.split()[1].split("/")
+                if idx >= len(splitted):
+                    continue
+                elif "<" in splitted[idx] and ">" in splitted[idx]:
+                    if splitted[idx] == "<artifactPath>":
+                        tmp_keys.append(tmp_key)
+                        continue
+                    elif idx == len(normalized_url_splitted) - 1 and \
+                            len(normalized_url_splitted) != len(splitted):
+                        continue
+                    else:
+                        tmp_keys.append(tmp_key)
+                elif splitted[idx] == path_part:
+                    if idx == len(normalized_url_splitted) - 1 and \
+                            len(normalized_url_splitted) != len(splitted):
+                        continue
+                    else:
+                        tmp_keys.append(tmp_key)
+            filtered_keys = tmp_keys
+            if len(filtered_keys) == 1 and \
+                    filtered_keys[0].split("/")[-1] == "<artifactPath>":
+                break
+
+        if len(filtered_keys) == 0:
+            raise AuthException("Cannot make an authorization decision. URL not found. URL: {0}".format(url))
+        elif len(filtered_keys) > 1:
+            raise AuthException("Cannot make an authorization decision. Multiple URLs found. URL: {0}".format(url))
+
+        filtered_key = filtered_keys[0]
+
+        for idx, path_part in enumerate(filtered_key.split()[1].split("/")):
+            if "<" in path_part and ">" in path_part:
+                if path_part == "<artifactPath>":
+                    parameters[path_part[1:-1]] = "/".join(normalized_url_splitted[idx:])
+                else:
+                    parameters[path_part[1:-1]] = normalized_url_splitted[idx]
+
+        return filtered_key, parameters
+
     def _internal_authorize(self, token_id):
         try:
             if not token_id:
     def _internal_authorize(self, token_id):
         try:
             if not token_id:
@@ -354,4 +579,4 @@ class Authenticator:
         if not self.next_db_prune_time or self.next_db_prune_time >= now:
             self.db.del_list("tokens", {"expires.lt": now})
             self.next_db_prune_time = self.periodin_db_pruning + now
         if not self.next_db_prune_time or self.next_db_prune_time >= now:
             self.db.del_list("tokens", {"expires.lt": now})
             self.next_db_prune_time = self.periodin_db_pruning + now
-            self.tokens_cache.clear()   # force to reload tokens from database
+            self.tokens_cache.clear()  # force to reload tokens from database