refreshable tokens

.gitignore

@@ -1,2 +1,6 @@
 __pycache__/
-ENV
+ENV
+config/
+*~
+.*~
+

auth.py

@@ -2,48 +2,76 @@ import time
 import connexion
 from jose import JWTError, jwt, jwe
 import json
+from jose.exceptions import ExpiredSignatureError
 import werkzeug
 import os
 import psycopg2
 from collections import namedtuple
 from pbkdf2 import crypt
 from loguru import logger
-
+import configparser
-DB_USER = os.environ["DB_USER"]
+import random
-DB_PASS = os.environ["DB_PASS"]
+import string
-DB_HOST = os.environ["DB_HOST"]
-DB_NAME = os.environ["DB_NAME"]
-
-JWT_ISSUER = os.environ["JWT_ISSUER"]
-
 
 
+DB_USER = ""
+DB_PASS = ""
+DB_HOST = ""
+DB_NAME = ""
+JWT_ISSUER = ""
+try:
+    DB_USER = os.environ["DB_USER"]
+    DB_PASS = os.environ["DB_PASS"]
+    DB_HOST = os.environ["DB_HOST"]
+    DB_NAME = os.environ["DB_NAME"]
+    JWT_ISSUER = os.environ["JWT_ISSUER"]
+except KeyError:
+    config = configparser.ConfigParser()
+    config.read('./config/config.ini')
+    DB_USER = config["database"]["user"]
+    DB_PASS = config["database"]["pass"]
+    DB_HOST = config["database"]["host"]
+    DB_NAME = config["database"]["name"]
+    JWT_ISSUER = config["jwt"]["issuer"]
 
 
 class NoUserException(Exception): 
     pass
 
+class NoTokenException(Exception): 
+    pass
+
+class NoValidTokenException(Exception): 
+    pass
+
 class ManyUsersException(Exception): 
     pass
 
+class ManyTokensException(Exception): 
+    pass
+
 class PasswordMismatchException(Exception): 
     pass
 
+class RefreshTokenExpiredException(Exception):
+    pass
+
 
 UserEntry = namedtuple('UserEntry', ['id', 'login', 'pwhash', 'expiry', 'claims'])
+RefreshTokenEntry = namedtuple('RefreshTokenEntry', ['id', 'salt', 'login', 'app', 'expiry'])
 
 JWT_PRIV_KEY = ""
 try:
     JWT_PRIV_KEY = os.environ["JWT_PRIV_KEY"]
 except KeyError:
-    with open('/opt/app/config/authservice.key', 'r') as f:
+    with open('./config/authservice.key', 'r') as f:
         JWT_PRIV_KEY = f.read()
 
 JWT_PUB_KEY = ""
 try:
     JWT_PUB_KEY = os.environ["JWT_PUB_KEY"]
 except KeyError:
-    with open('/opt/app/config/authservice.pub', 'r') as f:
+    with open('./config/authservice.pub', 'r') as f:
         JWT_PUB_KEY = f.read()
 
 
@@ -92,13 +120,57 @@ def getUserEntryFromDB(application: str, login: str):
         if conn:
             conn.close()
 
+def getRefreshTokenFromDB(application, login):
+    conn = None
+    cur = None
+    try:
+        conn = psycopg2.connect(user = DB_USER, password = DB_PASS,
+                                host = DB_HOST, database = DB_NAME)
+        conn.autocommit = False
+
+        with conn:
+            with conn.cursor() as cur:
+                cur.execute('SELECT u.id, u.expiry, a.name FROM user_t u, application_t a, user_application_mapping_t m' +
+                            '  WHERE u.login = %s AND ' +
+                            '  a.name = %s AND ' +
+                            '  a.id = m.application AND u.id = m."user"', 
+                            (login, application))
+                userObj = cur.fetchone()
+                logger.debug("userObj: {}".format(userObj))
+                if not userObj:
+                    raise NoUserException()
+                invObj = cur.fetchone()
+                if invObj:
+                    raise ManyUsersException()
+
+            with conn.cursor() as cur:
+                salt = ''.join(random.choice(string.ascii_letters + string.digits) for _ in range(64))
+                cur.execute('INSERT INTO token_t ("user", salt)  VALUES (%s, %s) RETURNING id', 
+                            (userObj[0], salt))
+                tokenObj = cur.fetchone()
+                logger.debug("tokenObj: {}".format(tokenObj))
+                if not tokenObj:
+                    raise NoTokenException()
+                invObj = cur.fetchone()
+                if invObj:
+                    raise ManyTokensException()
+
+        refreshTokenEntry = RefreshTokenEntry(id=tokenObj[0], salt=salt, login=login, app=userObj[2], expiry=userObj[1])
+
+        return refreshTokenEntry
+    except psycopg2.Error as err:
+        raise Exception("Error when connecting to database: {}".format(err))
+    finally:
+        if conn:
+            conn.close()
+
 def getUserEntry(application, login, password):
     userEntry = getUserEntryFromDB(application, login)
     if userEntry.pwhash != crypt(password, userEntry.pwhash):
         raise PasswordMismatchException()
     return userEntry
 
-def generateToken(**args):
+def generateToken(func, **args):
     try:
         body = args["body"]
 
@@ -121,23 +193,14 @@ def generateToken(**args):
             raise KeyError("Neither application, login and password nor encAleTuple given")
         
         logger.debug(f"Tuple: {application} {login} {password}")
-    
-        userEntry = getUserEntry(application, login, password)
-    
-        timestamp = int(time.time())
-        payload = {
-            "iss": JWT_ISSUER,
-            "iat": int(timestamp),
-            "exp": int(timestamp + userEntry.expiry),
-            "sub": str(userEntry.id),
-            "aud": application
-        }
-        logger.debug("claims: {}".format(userEntry.claims))
-        for claim in userEntry.claims.items():
-            logger.debug("add claim {}".format(claim))
-            payload[claim[0]] = claim[1]
 
-        return jwt.encode(payload, JWT_PRIV_KEY, algorithm='RS256')
+        return func(application, login, password)
+    except NoTokenException:
+        logger.error("no token created")
+        raise werkzeug.exceptions.Unauthorized()
+    except ManyTokensException:
+        logger.error("too many tokens created")
+        raise werkzeug.exceptions.Unauthorized()
     except NoUserException:
         logger.error("no user found, login or application wrong")
         raise werkzeug.exceptions.Unauthorized()
@@ -154,6 +217,55 @@ def generateToken(**args):
         logger.error("unspecific exception: {}".format(str(e)))
         raise werkzeug.exceptions.Unauthorized()
 
+
+def _makeSimpleToken(application, login, password, refresh=False):
+    userEntry = getUserEntry(application, login, password) if not refresh else getUserEntryFromDB(application, login)
+
+    timestamp = int(time.time())
+    payload = {
+        "iss": JWT_ISSUER,
+        "iat": int(timestamp),
+        "exp": int(timestamp + userEntry.expiry),
+        "sub": str(userEntry.id),
+        "aud": application
+    }
+    logger.debug("claims: {}".format(userEntry.claims))
+    for claim in userEntry.claims.items():
+        logger.debug("add claim {}".format(claim))
+        payload[claim[0]] = claim[1]
+
+    return jwt.encode(payload, JWT_PRIV_KEY, algorithm='RS256')
+
+def _makeRefreshToken(application, login, password):
+    refreshTokenEntry = getRefreshTokenFromDB(application, login)
+
+    timestamp = int(time.time())
+    payload = {
+        "iss": JWT_ISSUER,
+        "iat": int(timestamp),
+        "exp": int(timestamp + refreshTokenEntry.expiry),
+        "sub": str(refreshTokenEntry.login),
+        "xap": str(refreshTokenEntry.app),
+        "xid": str(refreshTokenEntry.id),
+        "xal": str(refreshTokenEntry.salt)
+    }
+
+    return jwt.encode(payload, JWT_PRIV_KEY, algorithm='RS256')
+
+def _makeRefreshableTokens(application, login, password):
+    authToken = _makeSimpleToken(application, login, password)
+    refreshToken = _makeRefreshToken(application, login, password)
+    return {
+        "authToken": authToken,
+        "refreshToken": refreshToken
+    }
+
+def generateSimpleToken(**args):
+    return generateToken(_makeSimpleToken, **args)
+
+def generateRefreshableTokens(**args):
+    return generateToken(_makeRefreshableTokens, **args)
+
 def getPubKey():
     return JWT_PUB_KEY
 
@@ -170,3 +282,82 @@ def testToken(user, token_info):
         "details": token_info
     }
 
+
+def checkAndInvalidateRefreshToken(login, xid, xal):
+    conn = None
+    cur = None
+    try:
+        conn = psycopg2.connect(user = DB_USER, password = DB_PASS,
+                                host = DB_HOST, database = DB_NAME)
+        conn.autocommit = False
+
+        with conn:
+            with conn.cursor() as cur:
+                cur.execute('SELECT t.id FROM token_t t, user_t u' +
+                            '  WHERE t.id = %s AND ' +
+                            '        t.salt = %s AND ' +
+                            '        t."user" = u.id AND ' +
+                            '        u.login = %s AND ' +
+                            '        t.valid = true',
+                            (xid, xal, login))
+                tokenObj = cur.fetchone()
+                logger.debug("tokenObj: {}".format(tokenObj))
+                if not tokenObj:
+                    raise NoValidTokenException()
+                invObj = cur.fetchone()
+                if invObj:
+                    raise ManyTokensException()
+
+            with conn.cursor() as cur:
+                cur.execute('UPDATE token_t SET valid = false WHERE id = %s', 
+                            [ xid ])
+    except psycopg2.Error as err:
+        raise Exception("Error when connecting to database: {}".format(err))
+    finally:
+        if conn:
+            conn.close()
+
+
+def refreshTokens(**args):
+    try:
+        refreshToken = args["body"]
+        refreshTokenObj = jwt.decode(refreshToken, JWT_PUB_KEY)
+        logger.info(str(refreshTokenObj))
+
+        checkAndInvalidateRefreshToken(refreshTokenObj["sub"], refreshTokenObj["xid"], refreshTokenObj["xal"])
+
+        authToken = _makeSimpleToken(refreshTokenObj["xap"], refreshTokenObj["sub"], "", refresh=True)
+        refreshToken = _makeRefreshToken(refreshTokenObj["xap"], refreshTokenObj["sub"], "")
+        return {
+            "authToken": authToken,
+            "refreshToken": refreshToken
+        }
+    except JWTError as e:
+        logger.error("jwt.decode failed: {}".format(e))
+        raise werkzeug.exceptions.Unauthorized()
+    except NoTokenException:
+        logger.error("no token created")
+        raise werkzeug.exceptions.Unauthorized()
+    except NoValidTokenException:
+        logger.error("no valid token found")
+        raise werkzeug.exceptions.Unauthorized()
+    except ManyTokensException:
+        logger.error("too many tokens created/found")
+        raise werkzeug.exceptions.Unauthorized()
+    except NoUserException:
+        logger.error("no user found, login or application wrong")
+        raise werkzeug.exceptions.Unauthorized()
+    except ManyUsersException:
+        logger.error("too many users found")
+        raise werkzeug.exceptions.Unauthorized()
+    except PasswordMismatchException:
+        logger.error("wrong password")
+        raise werkzeug.exceptions.Unauthorized()
+    except KeyError:
+        logger.error("application, login or password missing")
+        raise werkzeug.exceptions.Unauthorized()
+    #except Exception as e:
+    #    logger.error("unspecific exception: {}".format(str(e)))
+    #    raise werkzeug.exceptions.Unauthorized()
+
+

initial-schema.sql

@@ -12,6 +12,14 @@ create table user_t (
     expiry integer not null default 600
 );
 
+create sequence token_s start with 1 increment by 1;
+create table token_t (
+    id integer primary key not null default nextval('token_s'),
+    "user" integer not null references user_t (id),
+    salt varchar(64) not null,
+    valid boolean not null default true
+);
+
 create sequence claim_s start with 1 increment by 1;
 create table claim_t (
     id integer primary key not null default nextval('claim_s'),

openapi.yaml

@@ -7,8 +7,8 @@ paths:
   /token:
     post:
       tags: [ "JWT" ]
-      summary: Accept encrypted or clear set of credentials, return JWT token 
+      summary: Accepts encrypted or clear set of credentials, returns JWT token 
-      operationId: auth.generateToken
+      operationId: auth.generateSimpleToken
       requestBody:
         content:
           'application/json':
@@ -23,6 +23,42 @@ paths:
             'text/plain':
               schema:
                 type: string
+  /refreshable:
+    post:
+      tags: [ "JWT" ]
+      summary: Accepts encrypted or clear set of credentials, returns tuple of AuthToken and RefreshToken
+      operationId: auth.generateRefreshableTokens
+      requestBody:
+        content:
+          'application/json':
+            schema:
+              anyOf:
+                - $ref: '#/components/schemas/User'
+                - $ref: '#/components/schemas/EncUser'
+      responses:
+        '200':
+          description: Token tuple
+          content:
+            'application/json':
+              schema:
+                $ref: '#/components/schemas/TokenTuple'
+  /refresh:
+    post:
+      tags: [ "JWT" ]
+      summary: Accepts refresh token, returns tuple of AuthToken and RefreshToken
+      operationId: auth.refreshTokens
+      requestBody:
+        content:
+          'text/plain':
+            schema:
+              $ref: '#/components/schemas/RefreshToken'
+      responses:
+        '200':
+          description: Token tuple
+          content:
+            'application/json':
+              schema:
+                $ref: '#/components/schemas/TokenTuple'
   /test:
     get:
       tags: [ "Test" ]
@@ -83,3 +119,18 @@ components:
           type: string
         details:
           type: object
+    AuthToken:
+      description: Token for authentication purposes, just a string
+      type: string
+    RefreshToken:
+      description: Token for refresh purposes, just a string
+      type: string
+    TokenTuple:
+      description: Test Output
+      type: object
+      properties:
+        authToken:
+          $ref: '#/components/schemas/AuthToken'
+        refreshToken:
+          $ref: '#/components/schemas/RefreshToken'
+