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For DSpace 7 the REST authentication has been rewritten from the ground up. It makes use of Spring Security and to use JSON Web tokens instead of Tomcat session ID's. This was done to support stateless sessions. The implementation still uses Spring Security similar to DSpace 6.

Authenticate

To authenticate yourself, you have to send a POST request to the /api/authn/login endpoint with the following parameters:

parametervalue
user

email/id of user

passwordpassword of user

Example call with curl:

curl -v -X POST --data "user=test@dspacetest@dspace.com&password=p4ssword" "http://{springdspace-rest.url}/api/authn/login"

This call will return a JWT (JSON Web Token) in the response in the Authorization header according to the bearer scheme, this . This token has to be used in subsequent calls to provide your authentication details. For example:

curl -v "http://{spring-rest.url}/api/core/items" -H "Authorization: Bearer eyJhbG...COdbo"

Login using the HAL-browser

The HAL browser has been extended to support login inprovide a login form and to authenticate subsequent requests. You can find the login form in the top navigation menu where you can enter your credentials. After supplying valid credentials the token will be saved stored in a cookie and every request will get this token from the cookie and send it in the authorization header.

...

The authentication status can be checked by sending your received token to the status endpoint in the Authorization header:

curl -v "http://{spring-rest.url}/api/authn/status" -H "Authorization: Bearer eyJhbG...COdbo"

...

{
  "okay" : true,
  "authenticated" : true,
  "type" : "status",
  "_links" : {
    "eperson" : {
      "href" : "http://localhost:8080/dspace7-rest/api/eperson/epersons/2245f2c5-1bed-414b-a313-3fd2d2ec89d6"
    }
  },
  "_embedded" : {
    "eperson" : {
      "uuid" : "2245f2c5-1bed-414b-a313-3fd2d2ec89d6",
      "email" : "test@dspace.com",
      ...
      }
    }
  }
}

Fields

FieldMeaning
OkayTrue if
rest api
REST API is up and running, should never return false
AuthenticatedTrue if the token is valid, false if there was no token or the token wasn't valid
TypeType of the endpoint, "status" in this case
_links

returns a link to the authenticated eperson

_embeddedEmbeds the authenticated eperson


Logout

To logout and invalidate the token, send the token in the Authorization header with the bearer scheme to the following endpoint:

/api/authn/logout

E.G.

curl -v "http://{spring-rest.url}/api/authn/logout" -H "Authorization: Bearer eyJhbG...COdbo"

This will log the user out on every device /or browser.

JSON Web Token

The authentication token is a JSON Web Token (JWT) and is base64url encoded. For more information about JWT see this page:   https://jwt.io/introduction/

By default the JWT token will have a couple of claims already, which we can see if we decode the token:

ClaimData
eidContains the id of the eperson
sgContains the id's of the special groups to which a user belongs
expContains the expiration date when a token will expire

Add extra claims

Extra claims can be added by creating more beans To add a custom additional claim, you should implement a Spring bean which implement the JWTClaimProvider interface. Spring will scan for these beans implementing that interface and use them to automatically add new claims to the tokens.

The JWTClaimProvider interface requires three methods to be implemented:

getKey(): String  String  

  This method should return a string, this string will be used as key for the claim (for example "eid" for the eperson id claim)

getValue(Context, HttpServletRequest): Object

  This method should return the value of the claim, This can be any object, as long as it is Serialisable.

parseClaim(Context, HttpServletRequest, JWTClaimSet)

  This method should parse the claim when someone issues presents a token. In this method you should handle what has to happen with it (for example setting special groups on the context object)


NOTE: add @Component add @Component to your ClaimProviders so Spring can find them.

Refresh Token

Tokens are only valid for a configurable amount of time (see below). When a token is about to expire (Which can be checked with the the timestamp provided in the exp claim), you can request a new token with a new expiration time (by default 30 minutes). To do so send the token to the login endpoint without "user" and "password" parameters. As a response you'll get a new freshly issued token (again in the Authorization header of the response).

E.G.

curl -v "http://{spring-rest.url}/api/authn/login" -H "Authorization: Bearer eyJhbG...COdbo"

Which will return something like this:

HTTP/1.1 200 OK
Authorization: Bearer eyJhbGedoDfG...COdboS0df

Now you can use this new token to continue making authenticated requests.

...

The new stateless authentication introduced a few new properties that can be configured, these can all be found under modules/authentication.cfg:

jwt.token.secretManually define a key
here
that will be used (in combination with other strings) to sign the tokens. If this property is empty, a random key will be generated. Note that if you want to run DSpace in a cluster with multiple instances this has to be configured and every instance has to use the same key. It is also possible to pass this property with a value as an environment variable.
jwt.encryption.enabledBoolean property, defaults to false. If enabled the tokens will be encrypted and unreadable
clientside
client-side. As a downside enabling this makes the tokens a bit larger which will make the size of requests a bit larger, another disadvantage is not being able to use the data that is inside the token
clientside
. This means for example that the client cannot read the expiration claim and has to guess when it should refresh its token.
jwt.encryption.secretKey to use if encryption for
jwt
JWT is enabled
, if
. If none is specified and encryption is enabled, DSpace will generate a random one
, but when using clusters and encryption then one should be configured
. In a clustered setup, the encryption key should be the same on all instances.
jwt.token.expirationEnter the
time
period in minutes that a token should be valid
for
, by default this is 30
jwt.token.include.ipBoolean property, if true then the JWT signing key will also use the
ip-
IP address of the user
, this
. This will prevent the same token from being used from another
ip-address
IP address in case it gets stolen (similar to cookie theft). Defaults to true


Running DSpace in a clustered setup

One of the biggest advantages of this stateless authentication is that we can scale DSpace horizontally and run by running multiple instances of DSpace and side-by-side without complex configuration. Each node in the cluster will be able to send the same token to all of themunderstand the tokens. To do so a few properties have to be configured:

  • jwt.token.secret: This property has to be the same on every instance of DSpace. It's best to choose a long, non trivial

...

  • secret for extra security. Remember that properties can also be set through environment variables.
  • if jwt.encryption.enabled is set to true then jwt.encryption.secret also has to be configured and the same key has to be used on every instance.

Construction of signing key

The signing key of the used to sign and validate tokens is unique per eperson session. The signing key is constructed by

  • a random generated salt per user + 
  • The the server jwt.token.secret or a random one if empty +
  • The ip-the IP address of the user is if jwt.token.include.ip = true (default)

The session salt is saved in the EPerson table in the database and is used for:

  • Invalidating tokens: When someone logs out the salt will be removed from the database, so that

...

  • tokens won't be valid anymore since the sign key can't be constructed anymore.
  • Making sure the signing key has a valid length: The salt is always 32 bytes and the key to sign is required to be

...

  • >= 32 bytes

As long as a user refreshes his tokens before they expire, the session salt will not change. Once all tokens are expired and have not been refreshed (or if the user called the logout endpoint), the session salt will change on the next login.