Client Registration
Dynamic Client Registration (DCR)#
Dynamic client registration refers to the process by which a client submits a registration request to the Authorization server and how that request is served by the Authorization server. It is explained in the following specifications:
- For OpenID Connect relying parties
- For OAuth 2.0 client (without OpenID Connect features)
- Client management (CRUD) operations
- OpenBanking OpenID Dynamic Client Registration
Client Registration endpoint#
The URI to dynamically register a client to a Janssen Auth Server can be found by checking the registration_endpoint
claim of the OpenID Connect configuration reponse, typically deployed at
https://<my.jans.server>/.well-known/openid-configuration
Configuring Janssen AS to allow clients to dynamically register#
The Janssen Authorization server will serve a DCR request if the following configuration parameters are set:
dynamicRegistrationEnabled
:true
orfalse
dynamicRegistrationExpirationTime
: Expiration time in seconds for clients created with dynamic registration, 0 or -1 means never expiredcrForbidExpirationTimeInRequest
: Boolean value specifying whether to allow to set client's expiration time in seconds during dynamic registration.. Default value isfalse
.
Client expiration
Client expiration is set based on dynamicRegistrationExpirationTime
AS configuration property or otherwise
if dcrForbidExpirationTimeInRequest
is false
then it can be requested in Dynamic Client Registration Request via lifetime
parameter
which expected value in seconds.
Configure the Janssen AS using steps explained in the link
Client registration Requests#
Client registration request primarily does two things: Communicate client metadata to the authorization server, and optionally authenticate.
There are different ways in which the client metadata is communicated to the authorization server using dynamic client registration requests.
Using request body#
A minimal DCR request with only mandatory parameters, looks like the one below.
curl -X POST -k -H 'Content-Type: application/json' -i 'https://my.jans.server/jans-auth/restv1/register' \
--data '{"redirect_uris": ["https://my.jans.client/page"]}'
If the registration is successful, Janssen Server will respond with http response code 201
with JSON body as shown
in example below:
{
"allow_spontaneous_scopes": false,
"application_type": "web",
"rpt_as_jwt": false,
"registration_client_uri": "https://my.jans.server/jans-auth/restv1/register?client_id=85192707-a38c-496c-806c-ef01a6a3ae4a",
"tls_client_auth_subject_dn": "",
"run_introspection_script_before_jwt_creation": false,
"registration_access_token": "eaee20de-54ce-4217-b960-6b72b55e6cab",
"client_id": "85192707-a38c-496c-806c-ef01a6a3ae4a",
"token_endpoint_auth_method": "client_secret_basic",
"scope": "profile work_phone phone user_name device_sso openid permission uma_protection address email clientinfo org_name offline_access https://jans.io/auth/ssa.portal test https://jans.io/auth/ssa.admin https://jans.io/auth/ssa.developer",
"client_secret": "4148f812-92d6-4245-80e0-243524b3b6a4",
"client_id_issued_at": 1678700818,
"backchannel_logout_uri": "",
"backchannel_logout_session_required": false,
"client_name": "my.jans.client",
"par_lifetime": 600,
"lifetime": 3600,
"spontaneous_scopes": [],
"id_token_signed_response_alg": "RS256",
"access_token_as_jwt": false,
"grant_types": [
"authorization_code",
"refresh_token"
],
"subject_type": "pairwise",
"keep_client_authorization_after_expiration": false,
"require_par": false,
"redirect_uris": ["https://my.jans.client/page"],
"redirect_uris_regex": "",
"additional_audience": [],
"frontchannel_logout_session_required": false,
"client_secret_expires_at": 1678787218,
"access_token_signing_alg": "RS256",
"response_types": ["code"]
}
In a typical DCR request the client or developer calls the client registration endpoint with a set of client metadata as specified in RFC7591
curl -X POST -k -i 'https://my.jans.server/jans-auth/restv1/register' \
--data '{ \
"redirect_uris": ["https://client.example.org/cb"] \
"client_id": "c3BhdRkqfX", \
"client_secret": "bd136123eeffeef234235805d", \
"grant_types": ["authorization_code", "refresh_token"], \
"token_endpoint_auth_method": "client_secret_basic", \
"jwks_uri": "https://client.example.org/my_public_keys.jwks", \
"client_name": "My Example", \
"client_name#fr": "Mon Exemple" \
}'
Using signed request object (JWT)#
In some use-cases like FAPI implementation, DCR request payload is a JWT.
Example:
curl -X POST -k -H 'Content-Type: application/jwt' \
-H 'Accept: application/json' \
-i 'https://my-jans-server/jans-auth/restv1/register' \
--data 'eyJraWQiOiJrWTIyZXBUT......ueOg2HkjpggwAEP84jq9Q'
When such will be the nature of client registration requests, the following configuration properties should be set in the authorization server:
dcrSignatureValidationEnabled
- enables DCR signature validationdcrSignatureValidationJwksUri
- specifies JWKS URI for all DCR's validations.dcrSignatureValidationJwks
- specifies JWKS for all DCR's validations.
Configure the Janssen AS using steps explained in the link
Using software statement#
A signed assertion from a trusted party, a Software statement or Software Statement Assertion (SSA), is used to dynamically register clients to an Authorization server.
Example:
curl -X POST https://my.jans.server/jans-auth/restv1/register \
-H "Content-Type: application/json" \
--data-binary @- <<DATA \
{ "redirect_uris": [ "https://client.example.org/cab1" ], \
"software_statement":"eyJ0eXAi........j3ouyeYOv8", \
"jwks_uri":"https://my.portal/portal/jwks" \
} DATA
To enable client registrations using Software statements, the AS should be configured using the following configuration parameters:
softwareStatementValidationType
- The value of this variable is one of the following:- NONE - validation is skipped for software statement
- SCRIPT - (default), invokes
getSoftwareStatementJwks
of dynamic registration script which has to return jwks. - JWKS - claim name within software statement that has inlined JWKS
- JWKS_URI - claim name within software statement that points to JWKS URI that should lead to keys.
dcrSignatureValidationSoftwareStatementJwksURIClaim
- specifies claim name inside software statement that should point to JWKS URI.dcrSignatureValidationSoftwareStatementJwksClaim
- specifies claim name inside software statement. Value of claim should point to inlined JWKS.trustedSsaIssuers
- map of trusted SSA issuers with configuration (e.g. automatically granted scopes). When empty - no issuers validation is performed. When not empty - AS forces validation and each SSA must match at least one entry from list.automaticallyGrantedScopes
- automatically granted scopes for trusted issuer{ "https://trusted.as.com": { "automaticallyGrantedScopes": [ "a", "b" ] }, "https://another-trusted.as.com": { "automaticallyGrantedScopes": [ "d" ] } }
Configure the AS using steps explained in the link
Special mention about FAPI:#
In case of a typical client registration request in FAPI implementation, the request object which is a signed JWT (as seen in point 3) is also called an SSA (Software statement Assertion) or DCR payload. This SSA can contain the software_statement inside it which is also a signed JWT. Each of the JWTs, the outer JWT called the SSA and the inner JWT called the software_statement are signed by different entities - the TPP and OBIE respectively.
Security Pointers#
If dynamicRegistrationEnabled
is enabled in the Authorization Server, assess the following points to minimize
potential exposure of sensitive personal data:
trustedClientEnabled
anddynamicRegistrationPersistClientAuthorizations
properties determine whether clients are trusted and if consent should be sought from the user before releasing their personal data to the RPdynamicRegistrationScopesParamEnabled
controls whether default scopes are globally enabled. IfdynamicRegistrationScopesParamEnabled
istrue
then scopes defined as default will be automatically added to any dynamically registered client entry without consent of OP's administrator. Therefore, make an informed decision before setting this field totrue
.
CURL commands to configure Jans-auth server#
Jans-auth server is configured using Jans Config Api :
Obtain the access token#
curl -u "put_client_id_here:put_config_api_client_secret_here" https://<your.jans.server>/jans-auth/restv1/token \
-d "grant_type=client_credentials&scope=https://jans.io/oauth/jans-auth-server/config/properties.write"
Patch jans-auth server configurations#
Patch jans-auth server configurations to reflect anExampleConfigField
with the value anExampleConfigField_value
curl -X PATCH -k -H 'Content-Type: application/json-patch+json' \
-i 'https://<your.jans.server>/jans-config-api/api/v1/jans-auth-server/config' \
-H "Authorization: Bearer put_access_token_here" --data '[
{
"op": "add",
"path": "anExampleConfigField",
"value": "anExampleConfigField_value"
}
]'
For example, to patch the jans-auth server configurations to reflect dynamicRegistrationEnabled
with value as true
curl -X PATCH -k -H 'Content-Type: application/json-patch+json' \
-i 'https://<your.jans.server>/jans-config-api/api/v1/jans-auth-server/config' \
-H "Authorization: Bearer put_access_token_here" --data '[
{
"op": "add",
"path": "dynamicRegistrationEnabled",
"value": "true"
}
]'
Client metadata#
Command to obtain metadata schema
/opt/jans/jans-cli/config-cli.py --schema /components/schemas/Client
Output:
{
"dn": "string",
"inum": "string",
"displayName": "string",
"clientSecret": "string",
"frontChannelLogoutUri": "string",
"frontChannelLogoutSessionRequired": true,
"registrationAccessToken": "string",
"clientIdIssuedAt": "2022-08-31T10:39:31.385Z",
"clientSecretExpiresAt": "2022-08-31T10:39:31.385Z",
"redirectUris": [
"https://client.example.org/cb"
],
"claimRedirectUris": [
"string"
],
"responseTypes": [
"code"
],
"grantTypes": [
"authorization_code"
],
"applicationType": "web",
"contacts": [
"string"
],
"idTokenTokenBindingCnf": "string",
"logoUri": "string",
"clientUri": "string",
"policyUri": "string",
"tosUri": "string",
"jwksUri": "string",
"jwks": "{ \"keys\" : [ { \"e\" : \"AQAB\", \"n\" : \"gmlDX_mgMcHX..\" ] }",
"sectorIdentifierUri": "string",
"subjectType": "pairwise",
"idTokenSignedResponseAlg": "HS256",
"idTokenEncryptedResponseAlg": "RSA1_5",
"idTokenEncryptedResponseEnc": "A128CBC+HS256",
"userInfoSignedResponseAlg": "HS256",
"userInfoEncryptedResponseAlg": "RSA1_5",
"userInfoEncryptedResponseEnc": "A128CBC+HS256",
"requestObjectSigningAlg": "HS256",
"requestObjectEncryptionAlg": "RSA1_5",
"requestObjectEncryptionEnc": "A128CBC+HS256",
"tokenEndpointAuthMethod": "client_secret_basic",
"tokenEndpointAuthSigningAlg": "HS256",
"defaultMaxAge": 1000000,
"requireAuthTime": true,
"defaultAcrValues": [
"string"
],
"initiateLoginUri": "string",
"postLogoutRedirectUris": [
"https://client.example.org/logout/page1",
"https://client.example.org/logout/page2",
"https://client.example.org/logout/page3"
],
"requestUris": [
"string"
],
"scopes": [
"read write dolphin"
],
"claims": [
"string"
],
"trustedClient": false,
"lastAccessTime": "2022-08-31T10:39:31.385Z",
"lastLogonTime": "2022-08-31T10:39:31.385Z",
"persistClientAuthorizations": true,
"includeClaimsInIdToken": false,
"refreshTokenLifetime": 100000000,
"accessTokenLifetime": 100000000,
"customAttributes": [
{
"name": "name, displayName, birthdate, email",
"multiValued": true,
"values": [
"string"
]
}
],
"customObjectClasses": [
"string"
],
"rptAsJwt": true,
"accessTokenAsJwt": true,
"accessTokenSigningAlg": "HS256",
"disabled": false,
"authorizedOrigins": [
"string"
],
"softwareId": "4NRB1-0XZABZI9E6-5SM3R",
"softwareVersion": "2.1",
"softwareStatement": "string",
"attributes": {
"tlsClientAuthSubjectDn": "string",
"runIntrospectionScriptBeforeAccessTokenAsJwtCreationAndIncludeClaims": true,
"keepClientAuthorizationAfterExpiration": true,
"allowSpontaneousScopes": true,
"spontaneousScopes": [
"string"
],
"spontaneousScopeScriptDns": [
"string"
],
"updateTokenScriptDns": [
"string"
],
"backchannelLogoutUri": [
"string"
],
"backchannelLogoutSessionRequired": true,
"additionalAudience": [
"string"
],
"postAuthnScripts": [
"string"
],
"consentGatheringScripts": [
"string"
],
"introspectionScripts": [
"string"
],
"rptClaimsScripts": [
"string"
],
"ropcScripts": [
"string"
],
"parLifetime": 0,
"requirePar": true,
"jansAuthSignedRespAlg": "string",
"jansAuthEncRespAlg": "string",
"jansAuthEncRespEnc": "string",
"jansSubAttr": "string",
"redirectUrisRegex": "string",
"jansAuthorizedAcr": [
"string"
],
"jansDefaultPromptLogin": true
},
"backchannelTokenDeliveryMode": "poll",
"backchannelClientNotificationEndpoint": "string",
"backchannelAuthenticationRequestSigningAlg": "RS256",
"backchannelUserCodeParameter": true,
"expirationDate": "2022-08-31T10:39:31.385Z",
"deletable": false,
"jansId": "string",
"description": "string"
}
Signed DCR and SSA validation#
In OpenBanking case DCR (Dynamic Client Request) is signed and must contain SSA (Software Statement Assertion) inside it.
Non-Normative Example:
POST /register HTTP/1.1
Content-Type: application/jwt
Accept: application/json
Host: auth.bankone.com
eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJpc3MiOiJJREFtYX...
Decoded DCR Example:
{
"typ": "JWT",
"alg": "ES256",
"kid": "ABCD1234"
}
{
"iss": "Amazon TPPID",
"iat": 1492760444,
"exp": 1524296444,
"aud": "https://authn.gluu.org",
"scope": "openid makepayment",
"token_endpoint_auth_method": "private_key_jwt",
"grant_types": ["authorization_code", "refresh_token", "client_credentials"],
"response_types": ["code"],
"id_token_signed_response_alg": "ES256",
"request_object_signing_alg": "ES256",
"software_id": "65d1f27c-4aea-4549-9c21-60e495a7a86f",
"software_statement": "eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJpc3MiOiJlbXB0eSIsInN1YiI6IjEyMzQ1Njc4OTAiLCJuYW1lIjoiSm9obiBEb2UiLCJhZG1pbiI6dHJ1ZSwic2NvcGUiOiJzY29wZTEgc2NvcGUyIiwiY2xhaW1zIjoiY2xhaW0xIGNsYWltMiIsImlhdCI6MTY2OTgwNjc2MywiZXhwIjoxNjY5ODEwMzYzfQ.db0WQh2lmHkNYCWT8tSW684hqWTPJDTElppy42XM_lc"
}
{
Signature
}
AS has dcrSsaValidationConfigs
configuration value which holds json array. It can be used to validated both DCR and SSA.
Single item of this array has following properties:
- id - REQUIRED primary key for the entity
- type - REQUIRED either
ssa
ordcr
- displayName - Human friendly name in case we build an admin GUI for this
- description - Human friendly details
- scope - For SSA only -- list of allowed scopes the issuer can enable the client to request automatically. If not present, all scopes are allowed.
- allowed_claims - Any claims not listed in this list will be dropped. If not present, all claims are allowed.
- jwks - Public key
- jwks_uri - URI of public key
- issuers - For MTLS, list of issuers trusted
- configuration_endpoint - points to discovery page, e.g.
https://examle.com/.well-known/openid-configuration
- configuration_endpoint_claim - e.g.
ssa_jwks_endpoint
- shared_secret - for MTLS HMAC
One of jwks
, jwks_uri
or issuers
or configuration_endpoint
is required.
Non-normative example of dcrSsaValidationConfigs
[ {
"id" : "735ee1c0-895d-4398-9c1b-9ad852257cc0",
"type" : "DCR",
"scopes" : [ "read", "write" ],
"allowedClaims" : [ "exp", "iat" ],
"jwks" : "{jwks here}",
"issuers" : [ "Acme" ],
"sharedSecret" : "secret"
}, {
"id" : "7907cd0b-0f9f-4b4f-aaa2-0d0614546246",
"type" : "SSA",
"scopes" : [ "my_read", "my_write" ],
"allowedClaims" : [ "test_exp", "test_iat" ],
"jwks" : "{jwks here}",
"issuers" : [ "jans-auth" ],
"sharedSecret" : "secret"
}, {
"id" : "1e95c9b1-04d0-4440-9362-88f4e1e62d76",
"type" : "SSA",
"jwks" : "{jwks here}",
"issuers" : [ "empty" ],
"sharedSecret" : "secret"
} ]
Signed DCR validation#
DCR can be validated with two approaches.
Via dcrSsaValidationConfigs
configuration property - RECOMMENDED
When create entry in dcrSsaValidationConfigs
configuration property :
- type
MUST be equal to DCR
value
- issuers
MUST have value which equals to iss
claim in DCR.
Via other configuration properties
- trustedSsaIssuers - map of trusted SSA issuers with configuration (e.g. automatically granted scopes). When empty - no issuers validation is performed. When not empty - AS forces validation and each SSA must match at least one entry from list.
- automaticallyGrantedScopes - automatically granted scopes for trusted issuer
{ "https://trusted.as.com": { "automaticallyGrantedScopes": [ "a", "b" ] }, "https://another-trusted.as.com": { "automaticallyGrantedScopes": [ "d" ] } }
- dcrSignatureValidationJwks - specifies JWKS for DCR's validations
- dcrSignatureValidationJwksUri - specifies JWKS URI for DCR's validations
- dcrSignatureValidationSharedSecret - if HMAC is used, this is the shared secret
- dcrSignatureValidationEnabled - boolean value enables DCR signature validation. Default is false
- dcrSignatureValidationSoftwareStatementJwksURIClaim - specifies claim name inside software statement. Value of claim should point to JWKS URI
- dcrSignatureValidationSoftwareStatementJwksClaim - specifies claim name inside software statement. Value of claim should point to inlined JWKS
- dcrAuthorizationWithClientCredentials - boolean value indicating if DCR authorization to be performed using client credentials
SSA Validation#
SSA is validated based on softwareStatementValidationType
which is enum.
- softwareStatementValidationType=builtin - validation is performed against
dcrSsaValidationConfigs
configuration property, where type
MUST be equal toSSA
valueissuers
MUST have value which equals toiss
claim in DCR.- softwareStatementValidationType=script - jwks and hmac secret are returned by dynamic client registration script
- softwareStatementValidationType=jwks_uri, allows to specify jwks_uri claim name from software_statement. Claim name specified by
softwareStatementValidationClaimName
configuration property. - softwareStatementValidationType=jwks, allows to specify jwks claim name from software_statement. Claim name specified by
softwareStatementValidationClaimName
configuration property. - softwareStatementValidationType=none, no validation.
Customizing the behavior of the AS using Interception script#
Janssen's allows developers to register a client with the Authorization Server (AS) without any intervention by the administrator. By default, all clients are given the same default scopes and attributes. Through the use of an interception script, this behavior can be modified. These scripts can be used to analyze the registration request and apply customizations to the registered client. For example, a client can be given specific scopes by analyzing the Software Statement that is sent with the registration request.
Further reading here
The Use of Attestation in Dynamic Client Registration#
AS supports "The Use of Attestation in OAuth 2.0 Dynamic Client Registration" specification draft.
Specification draft does not define exact attestation request/response formats.
Thus AS supports Attestation calls to Verifier via ClientRegistrationType
custom script type.
Use createClient
method of ClientRegistrationType
to prevent client creation if attestation result does not satisfy expectation.
def createClient(self, context):
print "Client registration. CreateClient method"
registerRequest = context.getRegisterRequest()
configurationAttributes = context.getConfigurationAttibutes()
client = context.getClient()
# getting evidence as string or as JWT
evidenceAsString = registerRequest.getEvidence()
evidenceAsJwt = context.getEvidence()
# following code depends on attestation client used to make calls to Verifier
attestationResult = attestationClient.attestation(evidence)
if attestationResult.isFail:
print "Attestation result forbids client creation"
return False
print "Attestation result is OK"
return True
Configuration options
- dcrAttestationEvidenceRequired
- Boolean value indicating if DCR attestation evidence is required. Default value is false
.
If evidence
request parameter is not present and dcrAttestationEvidenceRequired
is true
AS returns stale_evidence
error:
HTTP/1.1 400 Bad Request
Content-Type: application/json
Cache-Control: no-store
Pragma: no-cache
{
"error": "stale_evidence",
"error_description": "The provided evidence is not current.",
"nonce": "lBjvTtuPbpzIaqyiAOOkrIol3WmflPUUepzUXNDFuUgMKUL"
}
It is common to get nonce
value from Attestation Server. In this case set dcrAttestationEvidenceRequired=false
and throw error from custom script.
def createClient(self, context):
evidenceAsString = registerRequest.getEvidence()
if StringHelper.isEmpty(evidenceAsString)
nonceFromVerifier = attestationClient.requestNonce()
context.createStaleEvidenceWebApplicationException(nonceFromVerifier)
return False
...
print "Attestation result is OK"
return True
context.createStaleEvidenceWebApplicationException(nonceFromVerifier)
leads to stale_evidence
error creation,
see example above (nonceFromVerifier
must be string value).
In case goal is to create own custom error, please use standard context.createWebApplicationException
methods and return False
from script to prevent client creation.
Example
entity = <construct error message>
context.createWebApplicationException(400, entity)
Dynamic registration custom attributes#
CRUD Operations#
Janssen Server allows client management through client configuration endpoint (RFC 7592).
JSON response to client registration request contains registration_client_uri
and
registration_access_token
data elements. The URI mentioned using registration_client_uri
provides functionality to
read, update and delete the client. This endpoint is a protected endpoint where request has to be authenticated using
access token registration_access_token
.
Read client metadata#
A read request to the same client that got created in earlier section should be as shown in the
example below. HTTP method GET
is used to send the request which signifies that it is a request to read
client
metadata.
curl -k -H 'Authorization: Bearer eaee20de-54ce-4217-b960-6b72b55e6cab' \
-i 'https://my.jans.server/jans-auth/restv1/register?client_id=85192707-a38c-496c-806c-ef01a6a3ae4a'
JSON response from Janssen Server will contain the current state of client metadata.
Update client metadata#
Client metadata can be updated by sending request with PUT
HTTP method to registration_client_uri
. Janssen Server
replaces current metadata with the one sent with update request as outlined in
the specification
Delete Client#
Client can be deleted by sending a request using DELETE
method to registration_client_uri
.
A successful delete action will invalidate the "client_id", "client_secret", and "registration_access_token" for this client, thereby preventing the "client_id" from being used at either the authorization endpoint or token endpoint of the authorization server.
Internationalization for Client metadata#
Created: 2022-07-21