# ungleichotp #

ungleich-otp is a full blown authentication and authorisation service
made for micro services.

The basic idea is that every micro service has a (long term) triple
constisting of (name, realm, seed) and creates time based tokens.

This basically revamps Kerberos in a simple way into the web area.

ungleichotp has been created and is maintained by [ungleich](https://ungleich.ch/).

Related documentation:

* [Python pyotp](https://pyotp.readthedocs.io/)
* [RFC6238, TOTP](https://tools.ietf.org/html/rfc6238)
* [RFC4120, Kerberos](https://tools.ietf.org/html/rfc4120)

## Overview ##

This repository the reference implementation of the ungleichotp server.


## Using the ungleichotpclient ##

The client can be used to test the ungleich-otp-server.

All client commands need the parameters --auth-name and --auth-realm.
Also either --auth-seed or --auth-token needs to be specified.
```
python manage.py ungleichotpclient create \
    --server-url https://otp.ungleich.ch/ungleichotp/
    --auth-name admin
    --auth-realm ungleich-admin
    [--auth-seed THESEEDFORADMIN]
    [--auth-token THECURRENTTOKEN]
```

### Creating new users

```
--name USERNAME --realm REALMOFUSER create
```

The seed is randomly created.

### Listing users

```
list
```

### Deleting users

```
--name USERNAME --realm REALMOFUSER delete
```


### Verifying a token is correct

Verify using:

```
--name USERNAME --realm REALMOFUSER --token TOKENTOBEVERIFIED verify
```

You can also verify using a seed:

```
--name USERNAME --realm REALMOFUSER --seed SEEDOFUSER verify
```


## Server Setup instructions ##

This is a standard django project and thus can be easily setup using

```
pip install -r requirements.txt
python manage.py createsuperuser
python manage.py runserver
```


## Realms ##

Access is granting/denied based on realms. There are two reserved
realms, all other realms can be used by the users:

### Reserved realms

Conceptually the realms "ungleich-admin" and "ungleich-auth" are
reserved for higher priviliged applications.

Usually there is only 1 entry in ungleich-admin that is used to
bootstrap and manage ungleich-otp.

All micro services that are trusted to authenticate another micro
service should have an entry in the ungleich-auth realm, which allows
them to verify a token of somebody else.

```
| Name             | Capabilities                               |
|------------------+--------------------------------------------|
| ungleich-admin   | authenticate, create, delete, list, update |
| ungleich-auth    | authenticate, verify                       |
| all other realms | authenticate                               |
```


## Verify using http POST  ##

Post a JSON object to the server at /ungleichotp/verify/ that
contains the following elements:

Request JSON object:

```
{
    auth_name: "auth-name",
    auth_realm: "auth-realm",
    auth_token: "current time based token",
    name: "name that wants to be authenticated",
    realm: "realm that wants to be authenticated",
    token: "token that wants to be authenticated"
}
```

Response JSON object:

Either HTTP 200 with
```
{
    status: "OK",
}
```

OR return code 403:

* If token for authenticating is wrong, you get

```
{"detail":"Incorrect authentication credentials."}
```

* If token that is being verified is wrong, you get

```
{"detail":"You do not have permission to perform this action."}
```

## Authorize the request ##

From the ungleichotp-server, you get a validated information that a
name on a realm authenticated successfully. The associated permissions
("authorization") is application specific and needs to be decided by
your application.


## Limitations ##

* Name, Realm and seed are hard coded to 128 bytes length.
  This can be changed, if necessary.
* Only python3 support for ungleichotp


## TODOs

- [x] (server) Serialize / input request
- [x] (server) Make seed read only
- [x] (server) Implement registering of new entries
- [x] (server) OTPSerializer: allow to read seed for admin
- [x] (server) Implement deleting entry
- [x] (server) Include verify in ModelSerializer
- [x] (server) Map name+realm == User (?)
  - name == name@realm
  - password is used for admin login (?)
  - seed
  - custom auth method
- [n] (server) Try to fake username for django based on name+realm (?)
  - No need
- [n] (server) maybe overwrite get_username()
  - No need
- [x] (server) Use Custom authentication  - needs to have a user!
- [x] (server) Implement creating new "User" by POST / Model based
- [n] (server) Remove hard coded JSON in /verify (no - good enough for the moment)
- [x] (server) Fully rename server from ungleichotp to ungleichotpserver
- [x] (security) Ensure that only the right realms can verify
- [x] (security) Ensure that only the right realms can manage
- [ ] (doc) Add proper documentation
- [ ] (server) Add tests for verify
- [ ] (server) Add tests for authentication
- [ ] (server) move totp constants into settings
- [ ] (server) move field lengths into settings
- [ ] (server) Document how admin vs. rest works
- [ ] (server, client) Make settings adjustable by environment - k8s/docker compatible
- [ ] (server, client) Read DB from outside (?) (fallback to sqlite)
- [x] (client) Establish auth using urllib
- [ ] (client) Bootstrap Django + DRF (including an object for CRUD)
- [ ] (client) Add custom authentication / remote auth
- [ ] (client) Show case: any realm vs. specific realm
- [x] (library) Write a "client library" that can use ungleichotp
- [x] (library) extract generic parts from server
- [ ] (library) upload to pypi



## Changelog

### 0.8, 2019-02-08

* Verify needed to call super()

### 0.6, 2018-11-18

* Reuse TokenSerializer for VerifySerializer logic

### 0.5, 2018-11-18

* Require authentication on all rest endpoints by token