1.2.21. Authentication¶
Interfaces for obtaining session and authorization data.
Note
We also strongly recommend you set up SSL to improve all authentication methods’ security.
1.2.21.1. Basic Authentication¶
Basic authentication (RFC 2617) is a quick and simple way to authenticate with CouchDB. The main drawback is the need to send user credentials with each request which may be insecure and could hurt operation performance (since CouchDB must compute the password hash with every request):
Request:
GET / HTTP/1.1
Accept: application/json
Authorization: Basic cm9vdDpyZWxheA==
Host: localhost:5984
Response:
HTTP/1.1 200 OK
Cache-Control: must-revalidate
Content-Length: 177
Content-Type: application/json
Date: Mon, 03 Dec 2012 00:44:47 GMT
Server: CouchDB (Erlang/OTP)
{
"couchdb":"Welcome",
"uuid":"0a959b9b8227188afc2ac26ccdf345a6",
"version":"1.3.0",
"vendor": {
"version":"1.3.0",
"name":"The Apache Software Foundation"
}
}
1.2.21.2. Cookie Authentication¶
For cookie authentication (RFC 2109) CouchDB generates a token that the
client can use for the next few requests to CouchDB. Tokens are valid until
a timeout. When CouchDB sees a valid token in a subsequent request, it will
authenticate the user by this token without requesting the password again. By
default, cookies are valid for 10 minutes, but it’s adjustable
. Also it’s possible to make cookies
persistent
.
To obtain the first token and thus authenticate a user for the first time, the username and password must be sent to the _session API.
1.2.21.2.1. /_session
¶
-
POST
/_session
¶ Initiates new session for specified user credentials by providing Cookie value.
Request Headers: - Content-Type –
- application/x-www-form-urlencoded
- application/json
Query Parameters: - next (string) – Enforces redirect after successful login to the specified location. This location is relative from server root. Optional.
Form Parameters: - name – User name
- password – Password
Response Headers: - Set-Cookie – Authorization token
Response JSON Object: - ok (boolean) – Operation status
- name (string) – Username
- roles (array) – List of user roles
Status Codes: - 200 OK – Successfully authenticated
- 302 Found – Redirect after successful authentication
- 401 Unauthorized – Username or password wasn’t recognized
Request:
POST /_session HTTP/1.1 Accept: application/json Content-Length: 24 Content-Type: application/x-www-form-urlencoded Host: localhost:5984 name=root&password=relax
It’s also possible to send data as JSON:
POST /_session HTTP/1.1 Accept: application/json Content-Length: 37 Content-Type: application/json Host: localhost:5984 { "name": "root", "password": "relax" }
Response:
HTTP/1.1 200 OK Cache-Control: must-revalidate Content-Length: 43 Content-Type: application/json Date: Mon, 03 Dec 2012 01:23:14 GMT Server: CouchDB (Erlang/OTP) Set-Cookie: AuthSession=cm9vdDo1MEJCRkYwMjq0LO0ylOIwShrgt8y-UkhI-c6BGw; Version=1; Path=/; HttpOnly {"ok":true,"name":"root","roles":["_admin"]}
If
next
query parameter was provided the response will trigger redirection to the specified location in case of successful authentication:Request:
POST /_session?next=/blog/_design/sofa/_rewrite/recent-posts HTTP/1.1 Accept: application/json Content-Type: application/x-www-form-urlencoded Host: localhost:5984 name=root&password=relax
Response:
HTTP/1.1 302 Moved Temporarily Cache-Control: must-revalidate Content-Length: 43 Content-Type: application/json Date: Mon, 03 Dec 2012 01:32:46 GMT Location: http://localhost:5984/blog/_design/sofa/_rewrite/recent-posts Server: CouchDB (Erlang/OTP) Set-Cookie: AuthSession=cm9vdDo1MEJDMDEzRTp7Vu5GKCkTxTVxwXbpXsBARQWnhQ; Version=1; Path=/; HttpOnly {"ok":true,"name":null,"roles":["_admin"]}
- Content-Type –
-
GET
/_session
¶ Returns information about the authenticated user, including a User Context Object, the authentication method and database that were used, and a list of configured authentication handlers on the server.
Query Parameters: - basic (boolean) – Accept Basic Auth by requesting this resource. Optional.
Response JSON Object: - ok (boolean) – Operation status
- userCtx (object) – User context for the current user
- info (object) – Server authentication configuration
Status Codes: - 200 OK – Successfully authenticated.
- 401 Unauthorized – Username or password wasn’t recognized.
Request:
GET /_session HTTP/1.1 Host: localhost:5984 Accept: application/json Cookie: AuthSession=cm9vdDo1MEJDMDQxRDpqb-Ta9QfP9hpdPjHLxNTKg_Hf9w
Response:
HTTP/1.1 200 OK Cache-Control: must-revalidate Content-Length: 175 Content-Type: application/json Date: Fri, 09 Aug 2013 20:27:45 GMT Server: CouchDB (Erlang/OTP) Set-Cookie: AuthSession=cm9vdDo1MjA1NTBDMTqmX2qKt1KDR--GUC80DQ6-Ew_XIw; Version=1; Path=/; HttpOnly { "info": { "authenticated": "cookie", "authentication_db": "_users", "authentication_handlers": [ "cookie", "default" ] }, "ok": true, "userCtx": { "name": "root", "roles": [ "_admin" ] } }
-
DELETE
/_session
¶ Closes user’s session by instructing the browser to clear the cookie. This does not invalidate the session from the server’s perspective, as there is no way to do this because CouchDB cookies are stateless. This means calling this endpoint is purely optional from a client perspective, and it does not protect against theft of a session cookie.
Status Codes: - 200 OK – Successfully close session.
Request:
DELETE /_session HTTP/1.1 Accept: application/json Cookie: AuthSession=cm9vdDo1MjA1NEVGMDo1QXNQkqC_0Qmgrk8Fw61_AzDeXw Host: localhost:5984
Response:
HTTP/1.1 200 OK Cache-Control: must-revalidate Content-Length: 12 Content-Type: application/json Date: Fri, 09 Aug 2013 20:30:12 GMT Server: CouchDB (Erlang/OTP) Set-Cookie: AuthSession=; Version=1; Path=/; HttpOnly { "ok": true }
1.2.21.3. Proxy Authentication¶
Note
To use this authentication method make sure that the
{chttpd_auth, proxy_authentication_handler}
value in added to the
list of the active chttpd/authentication_handlers
:
[chttpd]
authentication_handlers = {chttpd_auth, cookie_authentication_handler}, {chttpd_auth, proxy_authentication_handler}, {chttpd_auth, default_authentication_handler}
Proxy authentication is very useful in case your application already uses some external authentication service and you don’t want to duplicate users and their roles in CouchDB.
This authentication method allows creation of a User Context Object for remotely authenticated user. By default, the client just needs to pass specific headers to CouchDB with related requests:
X-Auth-CouchDB-UserName
: username;X-Auth-CouchDB-Roles
: comma-separated (,
) list of user roles;X-Auth-CouchDB-Token
: authentication token. Whenproxy_use_secret
is set (which is strongly recommended!), this header provides an HMAC of the username to authenticate and the secret token to prevent requests from untrusted sources.
Request:
GET /_session HTTP/1.1
Host: localhost:5984
Accept: application/json
Content-Type: application/json; charset=utf-8
X-Auth-CouchDB-Roles: users,blogger
X-Auth-CouchDB-UserName: foo
Response:
HTTP/1.1 200 OK
Cache-Control: must-revalidate
Content-Length: 190
Content-Type: application/json
Date: Fri, 14 Jun 2013 10:16:03 GMT
Server: CouchDB (Erlang/OTP)
{
"info": {
"authenticated": "proxy",
"authentication_db": "_users",
"authentication_handlers": [
"cookie",
"proxy",
"default"
]
},
"ok": true,
"userCtx": {
"name": "foo",
"roles": [
"users",
"blogger"
]
}
}
Note that you don’t need to request session to be authenticated by this method if all required HTTP headers are provided.
1.2.21.4. JWT Authentication¶
Note
To use this authentication method, make sure that the
{chttpd_auth, jwt_authentication_handler}
value is added to the
list of the active chttpd/authentication_handlers
:
[chttpd]
authentication_handlers = {chttpd_auth, cookie_authentication_handler}, {chttpd_auth, jwt_authentication_handler}, {chttpd_auth, default_authentication_handler}
JWT authentication
enables CouchDB to use externally-generated JWT tokens
instead of defining users or roles in the _users
database.
The JWT authentication handler requires that all JWT tokens are signed by a key that CouchDB has been configured to trust (there is no support for JWT’s “NONE” algorithm).
Additionally, CouchDB can be configured to reject JWT tokens that are
missing a configurable set of claims (e.g, a CouchDB administrator
could insist on the exp
claim).
All claims presented in a JWT token are validated if presented, regardless of whether they are required.
Two sections of config exist to configure JWT authentication;
The required_claims
config
setting is a comma-separated list of additional mandatory JWT claims
that must be present in any presented JWT token. A :code 400:Bad
Request is sent if any are missing.
The alg
claim is mandatory as it used to lookup the correct key for verifying the
signature.
The sub
claim is mandatory and is used as the CouchDB user’s name if the JWT token
is valid.
A private claim called _couchdb.roles
is optional. If presented,
as a JSON array of strings, it is used as the CouchDB user’s roles
list as long as the JWT token is valid.
; [jwt_keys]
; Configure at least one key here if using the JWT auth handler.
; If your JWT tokens do not include a "kid" attribute, use "_default"
; as the config key, otherwise use the kid as the config key.
; Examples
; hmac:_default = aGVsbG8=
; hmac:foo = aGVsbG8=
; The config values can represent symmetric and asymmetrics keys.
; For symmetrics keys, the value is base64 encoded;
; hmac:_default = aGVsbG8= # base64-encoded form of "hello"
; For asymmetric keys, the value is the PEM encoding of the public
; key with newlines replaced with the escape sequence \n.
; rsa:foo = -----BEGIN PUBLIC KEY-----\nMIIBIjAN...IDAQAB\n-----END PUBLIC KEY-----\n
; ec:bar = -----BEGIN PUBLIC KEY-----\nMHYwEAYHK...AzztRs\n-----END PUBLIC KEY-----\n
The jwt_key
section lists all the keys that this CouchDB server trusts. You
should ensure that all nodes of your cluster have the same list.
JWT tokens that do not include a kid
claim will be validated against the
$alg:_default
key.
It is mandatory to specify the algorithm associated with every key for security reasons (notably presenting a HMAC-signed token using an RSA or EC public key that the server trusts: https://auth0.com/blog/critical-vulnerabilities-in-json-web-token-libraries/).
Request:
GET /_session HTTP/1.1
Host: localhost:5984
Accept: application/json
Content-Type: application/json; charset=utf-8
Authorization: Bearer <JWT token>
Response:
HTTP/1.1 200 OK
Cache-Control: must-revalidate
Content-Length: 188
Content-Type: application/json
Date: Sun, 19 Apr 2020 08:29:15 GMT
Server: CouchDB (Erlang/OTP)
{
"info": {
"authenticated": "jwt",
"authentication_db": "_users",
"authentication_handlers": [
"cookie",
"proxy",
"default"
]
},
"ok": true,
"userCtx": {
"name": "foo",
"roles": [
"users",
"blogger"
]
}
}
Note that you don’t need to request session to be authenticated by this method if the required HTTP header is provided.