WORKERS AHEAD!

You are viewing the development documentation for the Apereo CAS server. The functionality presented here is not officially released yet. This is a work in progress and will be continually updated as development moves forward. You are most encouraged to test the changes presented.

Verifiable Credentials - OpenID Connect Authentication

OpenID Connect Authentication can be used in conjunction with Verifiable Credentials to provide a secure and decentralized way of verifying user identities. Verifiable Credentials are digital credentials that can be issued by trusted authorities and can be presented by users to prove their identity or attributes.

In this role, CAS acts as an OpenID Credential Issuer and extends its existing OpenID Connect capabilities with support for credential issuance, credential metadata publication, proof validation, nonce generation, and wallet-facing issuance flows.

The following capabilities are in place:

Issuer metadata is published via the .well-known/openid-credential-issuer endpoint.
CAS may issue credentials formats such as SD-JWT VC (selective disclosure), etc.
Dedicated endpoints for credential issuance and nonce generation are available.
Credential offers may be produced and shared with wallets.
Pre-authorized code flows may be used to obtain issuance-scoped access tokens.
Access tokens issued for verifiable credential flows may carry authorization context for one or more credential configurations.
Proofs may be validated to ensure possession of holder key material and to prevent replay.

Supported formats are:

dc+sd-jwt
jwt_vc_json
jwt_vc_json-ld

Overview

Support is enabled by including the following module in the overlay:

<dependency>
    <groupId>org.apereo.cas</groupId>
    <artifactId>cas-server-support-oidc-vc</artifactId>
    <version>${cas.version}</version>
</dependency>

implementation "org.apereo.cas:cas-server-support-oidc-vc:${project.'cas.version'}"

dependencyManagement {
    imports {
        mavenBom "org.apereo.cas:cas-server-support-bom:${project.'cas.version'}"
    }
}

dependencies {
    implementation "org.apereo.cas:cas-server-support-oidc-vc"
}

dependencies {
    /*
        The following platform references should be included automatically and are listed here for reference only.

        implementation enforcedPlatform("org.apereo.cas:cas-server-support-bom:${project.'cas.version'}")
        implementation platform(org.springframework.boot.gradle.plugin.SpringBootPlugin.BOM_COORDINATES)
        
    */
    implementation "org.apereo.cas:cas-server-support-oidc-vc"
}

The following settings and properties are available from the CAS configuration catalog:

_{The configuration settings listed below are tagged as Required in the CAS configuration metadata. This flag indicates that the presence of the setting may be needed to activate or affect the behavior of the CAS feature and generally should be reviewed, possibly owned and adjusted. If the setting is assigned a default value, you do not need to strictly put the setting in your copy of the configuration, but should review it nonetheless to make sure it matches your deployment expectations.}

_{The configuration settings listed below are tagged as Optional in the CAS configuration metadata. This
flag indicates that the presence of the setting
is not immediately necessary in the end-user CAS configuration, because a default value is assigned or
the activation of the feature is not conditionally controlled by the setting value. In other words, you should only include this field in your
configuration if you need to modify the default value or if you need to turn on the feature controlled by the setting.}

cas.authn.oidc.vc.issuer.credential-configurations.[key].claims.[key].disclosable=true

A claim that is candidate for Selective Disclosure. It is packaged inside the credential in a way that allows the Holder to selectively share it—or completely hide it—when presenting the credential to a Verifier (Relying Party).

org.apereo.cas.configuration.model.support.oidc.OidcVerifiableCredentialClaimProperties.

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Configuration properties can be included and activated using the following strategies.

Note

When possible, properties should be stored in lower-case kebab format, such as cas.property-name=value. The only possible exception to this rule is when naming actuator endpoints; The name of the actuator endpoints (i.e. ssoSessions) MUST remain in camelCase mode.

CAS properties can be specified using the Java configuration property syntax in any and all .properties files:

cas.authn.oidc.vc.issuer.credential-configurations.[key].claims.[key].disclosable=true

This is the most common form of property configuration that is recognized by CAS, regardless of the actual property source, which might in fact be managed separately outside the CAS environment, by another system or cloud framework.

CAS properties can be specified using the YAML syntax:

cas: 
  authn: 
    oidc: 
      vc: 
        issuer: 
          credential-configurations: 
            [key]: 
              claims: 
                [key]: 
                  disclosable: "true"

Note that YAML is very specific about structure and indentation. Be sure to verify the correctness of the final result with your YAML validator of choice.

CAS properties can be passed to the CAS web application as system properties, when the application is launched:

java -Dcas.authn.oidc.vc.issuer.credential-configurations.[key].claims.[key].disclosable="true" -jar build/libs/cas.war

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory. Note the placement of the system property which must be specified before the CAS web application is launched.

CAS properties can specified as system environment variables before the CAS web application is launched:

export CAS_AUTHN_OIDC_VC_ISSUER_CREDENTIAL_CONFIGURATIONS_[KEY]_CLAIMS_[KEY]_DISCLOSABLE="true"

java -jar build/libs/cas.war

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

CAS properties can be passed to the CAS web application as command-line arguments, when the application is launched:

java -jar build/libs/cas.war --cas.authn.oidc.vc.issuer.credential-configurations.[key].claims.[key].disclosable="true"

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

cas.authn.oidc.vc.issuer.credential-configurations.[key].claims.[key].display=

Control display settings for this claim.

org.apereo.cas.configuration.model.support.oidc.OidcVerifiableCredentialClaimProperties.

_{Copy Configuration Property

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Configuration properties can be included and activated using the following strategies.

Note

CAS properties can be specified using the Java configuration property syntax in any and all .properties files:

cas.authn.oidc.vc.issuer.credential-configurations.[key].claims.[key].display=...

CAS properties can be specified using the YAML syntax:

cas: 
  authn: 
    oidc: 
      vc: 
        issuer: 
          credential-configurations: 
            [key]: 
              claims: 
                [key]: 
                  display: "..."

Note that YAML is very specific about structure and indentation. Be sure to verify the correctness of the final result with your YAML validator of choice.

CAS properties can be passed to the CAS web application as system properties, when the application is launched:

java -Dcas.authn.oidc.vc.issuer.credential-configurations.[key].claims.[key].display="..." -jar build/libs/cas.war

CAS properties can specified as system environment variables before the CAS web application is launched:

export CAS_AUTHN_OIDC_VC_ISSUER_CREDENTIAL_CONFIGURATIONS_[KEY]_CLAIMS_[KEY]_DISPLAY="..."

java -jar build/libs/cas.war

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

CAS properties can be passed to the CAS web application as command-line arguments, when the application is launched:

java -jar build/libs/cas.war --cas.authn.oidc.vc.issuer.credential-configurations.[key].claims.[key].display="..."

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

cas.authn.oidc.vc.issuer.credential-configurations.[key].claims.[key].display[0].locale=en-US

Locale that controls this configuration's display.

org.apereo.cas.configuration.model.support.oidc.OidcVerifiableCredentialClaimProperties.CredentialClaimDisplay.

_{Copy Configuration Property

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Configuration properties can be included and activated using the following strategies.

Note

CAS properties can be specified using the Java configuration property syntax in any and all .properties files:

cas.authn.oidc.vc.issuer.credential-configurations.[key].claims.[key].display[0].locale=en-US

CAS properties can be specified using the YAML syntax:

cas: 
  authn: 
    oidc: 
      vc: 
        issuer: 
          credential-configurations: 
            [key]: 
              claims: 
                [key]: 
                  display[0]: 
                    locale: "en-US"

Note that YAML is very specific about structure and indentation. Be sure to verify the correctness of the final result with your YAML validator of choice.

CAS properties can be passed to the CAS web application as system properties, when the application is launched:

java -Dcas.authn.oidc.vc.issuer.credential-configurations.[key].claims.[key].display[0].locale="en-US" -jar build/libs/cas.war

CAS properties can specified as system environment variables before the CAS web application is launched:

export CAS_AUTHN_OIDC_VC_ISSUER_CREDENTIAL_CONFIGURATIONS_[KEY]_CLAIMS_[KEY]_DISPLAY[0]_LOCALE="en-US"

java -jar build/libs/cas.war

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

CAS properties can be passed to the CAS web application as command-line arguments, when the application is launched:

java -jar build/libs/cas.war --cas.authn.oidc.vc.issuer.credential-configurations.[key].claims.[key].display[0].locale="en-US"

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

cas.authn.oidc.vc.issuer.credential-configurations.[key].claims.[key].display[0].name=

Display name for this configuration.

org.apereo.cas.configuration.model.support.oidc.OidcVerifiableCredentialClaimProperties.CredentialClaimDisplay.

_{Copy Configuration Property

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Configuration properties can be included and activated using the following strategies.

Note

CAS properties can be specified using the Java configuration property syntax in any and all .properties files:

cas.authn.oidc.vc.issuer.credential-configurations.[key].claims.[key].display[0].name=...

CAS properties can be specified using the YAML syntax:

cas: 
  authn: 
    oidc: 
      vc: 
        issuer: 
          credential-configurations: 
            [key]: 
              claims: 
                [key]: 
                  display[0]: 
                    name: "..."

Note that YAML is very specific about structure and indentation. Be sure to verify the correctness of the final result with your YAML validator of choice.

CAS properties can be passed to the CAS web application as system properties, when the application is launched:

java -Dcas.authn.oidc.vc.issuer.credential-configurations.[key].claims.[key].display[0].name="..." -jar build/libs/cas.war

CAS properties can specified as system environment variables before the CAS web application is launched:

export CAS_AUTHN_OIDC_VC_ISSUER_CREDENTIAL_CONFIGURATIONS_[KEY]_CLAIMS_[KEY]_DISPLAY[0]_NAME="..."

java -jar build/libs/cas.war

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

CAS properties can be passed to the CAS web application as command-line arguments, when the application is launched:

java -jar build/libs/cas.war --cas.authn.oidc.vc.issuer.credential-configurations.[key].claims.[key].display[0].name="..."

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

cas.authn.oidc.vc.issuer.credential-configurations.[key].claims.[key].mandatory=

Whether this claim is mandatory. A claim (attribute) that must be present in the Verifiable Credential when it is issued. The Issuer requires this data to make the credential valid.

org.apereo.cas.configuration.model.support.oidc.OidcVerifiableCredentialClaimProperties.

_{Copy Configuration Property

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Configuration properties can be included and activated using the following strategies.

Note

CAS properties can be specified using the Java configuration property syntax in any and all .properties files:

cas.authn.oidc.vc.issuer.credential-configurations.[key].claims.[key].mandatory=...

CAS properties can be specified using the YAML syntax:

cas: 
  authn: 
    oidc: 
      vc: 
        issuer: 
          credential-configurations: 
            [key]: 
              claims: 
                [key]: 
                  mandatory: "..."

Note that YAML is very specific about structure and indentation. Be sure to verify the correctness of the final result with your YAML validator of choice.

CAS properties can be passed to the CAS web application as system properties, when the application is launched:

java -Dcas.authn.oidc.vc.issuer.credential-configurations.[key].claims.[key].mandatory="..." -jar build/libs/cas.war

CAS properties can specified as system environment variables before the CAS web application is launched:

export CAS_AUTHN_OIDC_VC_ISSUER_CREDENTIAL_CONFIGURATIONS_[KEY]_CLAIMS_[KEY]_MANDATORY="..."

java -jar build/libs/cas.war

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

CAS properties can be passed to the CAS web application as command-line arguments, when the application is launched:

java -jar build/libs/cas.war --cas.authn.oidc.vc.issuer.credential-configurations.[key].claims.[key].mandatory="..."

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

cas.authn.oidc.vc.issuer.credential-configurations.[key].credential-signing-alg-values-supported=ES256,RS256

Lists the signing algorithms supported by the issuer when producing the credential for this configuration. These algorithm identifiers are typically JOSE signature algorithms such as ES256 or RS256, and are advertised in issuer metadata so wallets know what credential signature formats are supported.

org.apereo.cas.configuration.model.support.oidc.OidcVerifiableCredentialConfigurationProperties.

_{Copy Configuration Property

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Configuration properties can be included and activated using the following strategies.

Note

CAS properties can be specified using the Java configuration property syntax in any and all .properties files:

cas.authn.oidc.vc.issuer.credential-configurations.[key].credential-signing-alg-values-supported=ES256,RS256

CAS properties can be specified using the YAML syntax:

cas: 
  authn: 
    oidc: 
      vc: 
        issuer: 
          credential-configurations: 
            [key]: 
              credential-signing-alg-values-supported: "ES256,RS256"

Note that YAML is very specific about structure and indentation. Be sure to verify the correctness of the final result with your YAML validator of choice.

CAS properties can be passed to the CAS web application as system properties, when the application is launched:

java -Dcas.authn.oidc.vc.issuer.credential-configurations.[key].credential-signing-alg-values-supported="ES256,RS256" -jar build/libs/cas.war

CAS properties can specified as system environment variables before the CAS web application is launched:

export CAS_AUTHN_OIDC_VC_ISSUER_CREDENTIAL_CONFIGURATIONS_[KEY]_CREDENTIAL_SIGNING_ALG_VALUES_SUPPORTED="ES256,RS256"

java -jar build/libs/cas.war

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

CAS properties can be passed to the CAS web application as command-line arguments, when the application is launched:

java -jar build/libs/cas.war --cas.authn.oidc.vc.issuer.credential-configurations.[key].credential-signing-alg-values-supported="ES256,RS256"

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

cas.authn.oidc.vc.issuer.credential-configurations.[key].cryptographic-binding-methods-supported=jwk

Lists the supported cryptographic binding methods for this credential. These values indicate how the issued credential may be bound to key material controlled by the wallet or holder. A common value is jwk, which indicates binding via a JSON Web Key.

org.apereo.cas.configuration.model.support.oidc.OidcVerifiableCredentialConfigurationProperties.

_{Copy Configuration Property

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Configuration properties can be included and activated using the following strategies.

Note

CAS properties can be specified using the Java configuration property syntax in any and all .properties files:

cas.authn.oidc.vc.issuer.credential-configurations.[key].cryptographic-binding-methods-supported=jwk

CAS properties can be specified using the YAML syntax:

cas: 
  authn: 
    oidc: 
      vc: 
        issuer: 
          credential-configurations: 
            [key]: 
              cryptographic-binding-methods-supported: "jwk"

Note that YAML is very specific about structure and indentation. Be sure to verify the correctness of the final result with your YAML validator of choice.

CAS properties can be passed to the CAS web application as system properties, when the application is launched:

java -Dcas.authn.oidc.vc.issuer.credential-configurations.[key].cryptographic-binding-methods-supported="jwk" -jar build/libs/cas.war

CAS properties can specified as system environment variables before the CAS web application is launched:

export CAS_AUTHN_OIDC_VC_ISSUER_CREDENTIAL_CONFIGURATIONS_[KEY]_CRYPTOGRAPHIC_BINDING_METHODS_SUPPORTED="jwk"

java -jar build/libs/cas.war

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

CAS properties can be passed to the CAS web application as command-line arguments, when the application is launched:

java -jar build/libs/cas.war --cas.authn.oidc.vc.issuer.credential-configurations.[key].cryptographic-binding-methods-supported="jwk"

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

cas.authn.oidc.vc.issuer.credential-configurations.[key].display=org.apereo.cas.configuration.model.support.oidc.OidcVerifiableCredentialConfigurationProperties$CredentialConfigurationDisplay@378bd86d

Control display settings of this credential configuration used in metadata generation.

org.apereo.cas.configuration.model.support.oidc.OidcVerifiableCredentialConfigurationProperties.

_{Copy Configuration Property

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Configuration properties can be included and activated using the following strategies.

Note

CAS properties can be specified using the Java configuration property syntax in any and all .properties files:

cas.authn.oidc.vc.issuer.credential-configurations.[key].display=org.apereo.cas.configuration.model.support.oidc.OidcVerifiableCredentialConfigurationProperties$CredentialConfigurationDisplay@378bd86d

CAS properties can be specified using the YAML syntax:

cas: 
  authn: 
    oidc: 
      vc: 
        issuer: 
          credential-configurations: 
            [key]: 
              display: "org.apereo.cas.configuration.model.support.oidc.OidcVerifiableCredentialConfigurationProperties$CredentialConfigurationDisplay@378bd86d"

Note that YAML is very specific about structure and indentation. Be sure to verify the correctness of the final result with your YAML validator of choice.

CAS properties can be passed to the CAS web application as system properties, when the application is launched:

java -Dcas.authn.oidc.vc.issuer.credential-configurations.[key].display="org.apereo.cas.configuration.model.support.oidc.OidcVerifiableCredentialConfigurationProperties$CredentialConfigurationDisplay@378bd86d" -jar build/libs/cas.war

CAS properties can specified as system environment variables before the CAS web application is launched:

export CAS_AUTHN_OIDC_VC_ISSUER_CREDENTIAL_CONFIGURATIONS_[KEY]_DISPLAY="org.apereo.cas.configuration.model.support.oidc.OidcVerifiableCredentialConfigurationProperties$CredentialConfigurationDisplay@378bd86d"

java -jar build/libs/cas.war

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

CAS properties can be passed to the CAS web application as command-line arguments, when the application is launched:

java -jar build/libs/cas.war --cas.authn.oidc.vc.issuer.credential-configurations.[key].display="org.apereo.cas.configuration.model.support.oidc.OidcVerifiableCredentialConfigurationProperties$CredentialConfigurationDisplay@378bd86d"

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

cas.authn.oidc.vc.issuer.credential-configurations.[key].display[0].background-color=

Background color for this configuration.

org.apereo.cas.configuration.model.support.oidc.OidcVerifiableCredentialConfigurationProperties.CredentialConfigurationDisplay.

_{Copy Configuration Property

Copied!} _{How can I configure this property?}

Configuration properties can be included and activated using the following strategies.

Note

CAS properties can be specified using the Java configuration property syntax in any and all .properties files:

cas.authn.oidc.vc.issuer.credential-configurations.[key].display[0].background-color=...

CAS properties can be specified using the YAML syntax:

cas: 
  authn: 
    oidc: 
      vc: 
        issuer: 
          credential-configurations: 
            [key]: 
              display[0]: 
                background-color: "..."

Note that YAML is very specific about structure and indentation. Be sure to verify the correctness of the final result with your YAML validator of choice.

CAS properties can be passed to the CAS web application as system properties, when the application is launched:

java -Dcas.authn.oidc.vc.issuer.credential-configurations.[key].display[0].background-color="..." -jar build/libs/cas.war

CAS properties can specified as system environment variables before the CAS web application is launched:

export CAS_AUTHN_OIDC_VC_ISSUER_CREDENTIAL_CONFIGURATIONS_[KEY]_DISPLAY[0]_BACKGROUND_COLOR="..."

java -jar build/libs/cas.war

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

CAS properties can be passed to the CAS web application as command-line arguments, when the application is launched:

java -jar build/libs/cas.war --cas.authn.oidc.vc.issuer.credential-configurations.[key].display[0].background-color="..."

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

cas.authn.oidc.vc.issuer.credential-configurations.[key].display[0].description=My verifiable credential that belongs to my organization

Description for this configuration.

org.apereo.cas.configuration.model.support.oidc.OidcVerifiableCredentialConfigurationProperties.CredentialConfigurationDisplay.

_{Copy Configuration Property

Copied!} _{How can I configure this property?}

Configuration properties can be included and activated using the following strategies.

Note

CAS properties can be specified using the Java configuration property syntax in any and all .properties files:

cas.authn.oidc.vc.issuer.credential-configurations.[key].display[0].description=My verifiable credential that belongs to my organization

CAS properties can be specified using the YAML syntax:

cas: 
  authn: 
    oidc: 
      vc: 
        issuer: 
          credential-configurations: 
            [key]: 
              display[0]: 
                description: "My verifiable credential that belongs to my organization"

Note that YAML is very specific about structure and indentation. Be sure to verify the correctness of the final result with your YAML validator of choice.

CAS properties can be passed to the CAS web application as system properties, when the application is launched:

java -Dcas.authn.oidc.vc.issuer.credential-configurations.[key].display[0].description="My verifiable credential that belongs to my organization" -jar build/libs/cas.war

CAS properties can specified as system environment variables before the CAS web application is launched:

export CAS_AUTHN_OIDC_VC_ISSUER_CREDENTIAL_CONFIGURATIONS_[KEY]_DISPLAY[0]_DESCRIPTION="My verifiable credential that belongs to my organization"

java -jar build/libs/cas.war

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

CAS properties can be passed to the CAS web application as command-line arguments, when the application is launched:

java -jar build/libs/cas.war --cas.authn.oidc.vc.issuer.credential-configurations.[key].display[0].description="My verifiable credential that belongs to my organization"

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

cas.authn.oidc.vc.issuer.credential-configurations.[key].display[0].locale=en-US

Locale that controls this configuration's display.

org.apereo.cas.configuration.model.support.oidc.OidcVerifiableCredentialConfigurationProperties.CredentialConfigurationDisplay.

_{Copy Configuration Property

Copied!} _{How can I configure this property?}

Configuration properties can be included and activated using the following strategies.

Note

CAS properties can be specified using the Java configuration property syntax in any and all .properties files:

cas.authn.oidc.vc.issuer.credential-configurations.[key].display[0].locale=en-US

CAS properties can be specified using the YAML syntax:

cas: 
  authn: 
    oidc: 
      vc: 
        issuer: 
          credential-configurations: 
            [key]: 
              display[0]: 
                locale: "en-US"

Note that YAML is very specific about structure and indentation. Be sure to verify the correctness of the final result with your YAML validator of choice.

CAS properties can be passed to the CAS web application as system properties, when the application is launched:

java -Dcas.authn.oidc.vc.issuer.credential-configurations.[key].display[0].locale="en-US" -jar build/libs/cas.war

CAS properties can specified as system environment variables before the CAS web application is launched:

export CAS_AUTHN_OIDC_VC_ISSUER_CREDENTIAL_CONFIGURATIONS_[KEY]_DISPLAY[0]_LOCALE="en-US"

java -jar build/libs/cas.war

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

CAS properties can be passed to the CAS web application as command-line arguments, when the application is launched:

java -jar build/libs/cas.war --cas.authn.oidc.vc.issuer.credential-configurations.[key].display[0].locale="en-US"

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

cas.authn.oidc.vc.issuer.credential-configurations.[key].display[0].logo=https://apereo.github.io/cas/images/cas_logo.png

Logo url.

org.apereo.cas.configuration.model.support.oidc.OidcVerifiableCredentialConfigurationProperties.CredentialConfigurationDisplay.

_{Copy Configuration Property

Copied!} _{How can I configure this property?}

Configuration properties can be included and activated using the following strategies.

Note

CAS properties can be specified using the Java configuration property syntax in any and all .properties files:

cas.authn.oidc.vc.issuer.credential-configurations.[key].display[0].logo=https://apereo.github.io/cas/images/cas_logo.png

CAS properties can be specified using the YAML syntax:

cas: 
  authn: 
    oidc: 
      vc: 
        issuer: 
          credential-configurations: 
            [key]: 
              display[0]: 
                logo: "https://apereo.github.io/cas/images/cas_logo.png"

Note that YAML is very specific about structure and indentation. Be sure to verify the correctness of the final result with your YAML validator of choice.

CAS properties can be passed to the CAS web application as system properties, when the application is launched:

java -Dcas.authn.oidc.vc.issuer.credential-configurations.[key].display[0].logo="https://apereo.github.io/cas/images/cas_logo.png" -jar build/libs/cas.war

CAS properties can specified as system environment variables before the CAS web application is launched:

export CAS_AUTHN_OIDC_VC_ISSUER_CREDENTIAL_CONFIGURATIONS_[KEY]_DISPLAY[0]_LOGO="https://apereo.github.io/cas/images/cas_logo.png"

java -jar build/libs/cas.war

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

CAS properties can be passed to the CAS web application as command-line arguments, when the application is launched:

java -jar build/libs/cas.war --cas.authn.oidc.vc.issuer.credential-configurations.[key].display[0].logo="https://apereo.github.io/cas/images/cas_logo.png"

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

cas.authn.oidc.vc.issuer.credential-configurations.[key].display[0].name=My Verifiable Credential

Display name for this configuration.

org.apereo.cas.configuration.model.support.oidc.OidcVerifiableCredentialConfigurationProperties.CredentialConfigurationDisplay.

_{Copy Configuration Property

Copied!} _{How can I configure this property?}

Configuration properties can be included and activated using the following strategies.

Note

CAS properties can be specified using the Java configuration property syntax in any and all .properties files:

cas.authn.oidc.vc.issuer.credential-configurations.[key].display[0].name=My Verifiable Credential

CAS properties can be specified using the YAML syntax:

cas: 
  authn: 
    oidc: 
      vc: 
        issuer: 
          credential-configurations: 
            [key]: 
              display[0]: 
                name: "My Verifiable Credential"

Note that YAML is very specific about structure and indentation. Be sure to verify the correctness of the final result with your YAML validator of choice.

CAS properties can be passed to the CAS web application as system properties, when the application is launched:

java -Dcas.authn.oidc.vc.issuer.credential-configurations.[key].display[0].name="My Verifiable Credential" -jar build/libs/cas.war

CAS properties can specified as system environment variables before the CAS web application is launched:

export CAS_AUTHN_OIDC_VC_ISSUER_CREDENTIAL_CONFIGURATIONS_[KEY]_DISPLAY[0]_NAME="My Verifiable Credential"

java -jar build/libs/cas.war

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

CAS properties can be passed to the CAS web application as command-line arguments, when the application is launched:

java -jar build/libs/cas.war --cas.authn.oidc.vc.issuer.credential-configurations.[key].display[0].name="My Verifiable Credential"

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

cas.authn.oidc.vc.issuer.credential-configurations.[key].display[0].text-color=

Text color for this configuration.

org.apereo.cas.configuration.model.support.oidc.OidcVerifiableCredentialConfigurationProperties.CredentialConfigurationDisplay.

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Configuration properties can be included and activated using the following strategies.

Note

CAS properties can be specified using the Java configuration property syntax in any and all .properties files:

cas.authn.oidc.vc.issuer.credential-configurations.[key].display[0].text-color=...

CAS properties can be specified using the YAML syntax:

cas: 
  authn: 
    oidc: 
      vc: 
        issuer: 
          credential-configurations: 
            [key]: 
              display[0]: 
                text-color: "..."

Note that YAML is very specific about structure and indentation. Be sure to verify the correctness of the final result with your YAML validator of choice.

CAS properties can be passed to the CAS web application as system properties, when the application is launched:

java -Dcas.authn.oidc.vc.issuer.credential-configurations.[key].display[0].text-color="..." -jar build/libs/cas.war

CAS properties can specified as system environment variables before the CAS web application is launched:

export CAS_AUTHN_OIDC_VC_ISSUER_CREDENTIAL_CONFIGURATIONS_[KEY]_DISPLAY[0]_TEXT_COLOR="..."

java -jar build/libs/cas.war

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

CAS properties can be passed to the CAS web application as command-line arguments, when the application is launched:

java -jar build/libs/cas.war --cas.authn.oidc.vc.issuer.credential-configurations.[key].display[0].text-color="..."

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

cas.authn.oidc.vc.issuer.credential-configurations.[key].format=OidcVerifiableCredentialConfigurationProperties.CredentialConfigurationFormats.DC_SD_JWT(dc+sd-jwt)

Defines the credential format issued for this configuration. Typical values depend on the verifiable credential profile supported by the issuer, such as JWT-based or SD-JWT-based credentials. This value is published in issuer metadata and is used by wallets to determine how the credential request and response should be processed. Available values are as follows:

DC_SD_JWT: A Data Integrity Claims (DC) credential encoded as an SD-JWT, supporting selective disclosure of claims while preserving cryptographic integrity.
JWT_VC_JSON: It is a JSON-based string that represents the credential as a base64url-encoded JWT.
JWT_VC_JSON_LD: This format includes a @context URLs that maps data properties to universal schemas. Every field has a strict, globally defined semantic meaning.

org.apereo.cas.configuration.model.support.oidc.OidcVerifiableCredentialConfigurationProperties.

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Configuration properties can be included and activated using the following strategies.

Note

CAS properties can be specified using the Java configuration property syntax in any and all .properties files:

cas.authn.oidc.vc.issuer.credential-configurations.[key].format=OidcVerifiableCredentialConfigurationProperties.CredentialConfigurationFormats.DC_SD_JWT(dc+sd-jwt)

CAS properties can be specified using the YAML syntax:

cas: 
  authn: 
    oidc: 
      vc: 
        issuer: 
          credential-configurations: 
            [key]: 
              format: "OidcVerifiableCredentialConfigurationProperties.CredentialConfigurationFormats.DC_SD_JWT(dc+sd-jwt)"

Note that YAML is very specific about structure and indentation. Be sure to verify the correctness of the final result with your YAML validator of choice.

CAS properties can be passed to the CAS web application as system properties, when the application is launched:

java -Dcas.authn.oidc.vc.issuer.credential-configurations.[key].format="OidcVerifiableCredentialConfigurationProperties.CredentialConfigurationFormats.DC_SD_JWT(dc+sd-jwt)" -jar build/libs/cas.war

CAS properties can specified as system environment variables before the CAS web application is launched:

export CAS_AUTHN_OIDC_VC_ISSUER_CREDENTIAL_CONFIGURATIONS_[KEY]_FORMAT="OidcVerifiableCredentialConfigurationProperties.CredentialConfigurationFormats.DC_SD_JWT(dc+sd-jwt)"

java -jar build/libs/cas.war

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

CAS properties can be passed to the CAS web application as command-line arguments, when the application is launched:

java -jar build/libs/cas.war --cas.authn.oidc.vc.issuer.credential-configurations.[key].format="OidcVerifiableCredentialConfigurationProperties.CredentialConfigurationFormats.DC_SD_JWT(dc+sd-jwt)"

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

cas.authn.oidc.vc.issuer.credential-configurations.[key].proof-signing-alg-values-supported=ES256,RS256

Lists the signing algorithms supported for proof validation when the wallet submits proof material as part of a credential request. These values represent the algorithms CAS accepts when verifying proof-of-possession tokens or JWT-based proofs presented by the holder.

org.apereo.cas.configuration.model.support.oidc.OidcVerifiableCredentialConfigurationProperties.

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Configuration properties can be included and activated using the following strategies.

Note

CAS properties can be specified using the Java configuration property syntax in any and all .properties files:

cas.authn.oidc.vc.issuer.credential-configurations.[key].proof-signing-alg-values-supported=ES256,RS256

CAS properties can be specified using the YAML syntax:

cas: 
  authn: 
    oidc: 
      vc: 
        issuer: 
          credential-configurations: 
            [key]: 
              proof-signing-alg-values-supported: "ES256,RS256"

Note that YAML is very specific about structure and indentation. Be sure to verify the correctness of the final result with your YAML validator of choice.

CAS properties can be passed to the CAS web application as system properties, when the application is launched:

java -Dcas.authn.oidc.vc.issuer.credential-configurations.[key].proof-signing-alg-values-supported="ES256,RS256" -jar build/libs/cas.war

CAS properties can specified as system environment variables before the CAS web application is launched:

export CAS_AUTHN_OIDC_VC_ISSUER_CREDENTIAL_CONFIGURATIONS_[KEY]_PROOF_SIGNING_ALG_VALUES_SUPPORTED="ES256,RS256"

java -jar build/libs/cas.war

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

CAS properties can be passed to the CAS web application as command-line arguments, when the application is launched:

java -jar build/libs/cas.war --cas.authn.oidc.vc.issuer.credential-configurations.[key].proof-signing-alg-values-supported="ES256,RS256"

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

cas.authn.oidc.vc.issuer.credential-configurations.[key].scope=

OAuth scope associated with this credential configuration. This scope may be used during authorization and token issuance to indicate that the client or wallet is requesting permission to obtain this specific type of verifiable credential.

org.apereo.cas.configuration.model.support.oidc.OidcVerifiableCredentialConfigurationProperties.

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Configuration properties can be included and activated using the following strategies.

Note

CAS properties can be specified using the Java configuration property syntax in any and all .properties files:

cas.authn.oidc.vc.issuer.credential-configurations.[key].scope=...

CAS properties can be specified using the YAML syntax:

cas: 
  authn: 
    oidc: 
      vc: 
        issuer: 
          credential-configurations: 
            [key]: 
              scope: "..."

Note that YAML is very specific about structure and indentation. Be sure to verify the correctness of the final result with your YAML validator of choice.

CAS properties can be passed to the CAS web application as system properties, when the application is launched:

java -Dcas.authn.oidc.vc.issuer.credential-configurations.[key].scope="..." -jar build/libs/cas.war

CAS properties can specified as system environment variables before the CAS web application is launched:

export CAS_AUTHN_OIDC_VC_ISSUER_CREDENTIAL_CONFIGURATIONS_[KEY]_SCOPE="..."

java -jar build/libs/cas.war

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

CAS properties can be passed to the CAS web application as command-line arguments, when the application is launched:

java -jar build/libs/cas.war --cas.authn.oidc.vc.issuer.credential-configurations.[key].scope="..."

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

cas.authn.oidc.vc.metadata.include-claims=true

Whether claims should be included in the metadata.

org.apereo.cas.configuration.model.support.oidc.OidcVerifiableCredentialsMetadataProperties.

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Configuration properties can be included and activated using the following strategies.

Note

CAS properties can be specified using the Java configuration property syntax in any and all .properties files:

cas.authn.oidc.vc.metadata.include-claims=true

CAS properties can be specified using the YAML syntax:

cas: 
  authn: 
    oidc: 
      vc: 
        metadata: 
          include-claims: "true"

Note that YAML is very specific about structure and indentation. Be sure to verify the correctness of the final result with your YAML validator of choice.

CAS properties can be passed to the CAS web application as system properties, when the application is launched:

java -Dcas.authn.oidc.vc.metadata.include-claims="true" -jar build/libs/cas.war

CAS properties can specified as system environment variables before the CAS web application is launched:

export CAS_AUTHN_OIDC_VC_METADATA_INCLUDE_CLAIMS="true"

java -jar build/libs/cas.war

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

CAS properties can be passed to the CAS web application as command-line arguments, when the application is launched:

java -jar build/libs/cas.war --cas.authn.oidc.vc.metadata.include-claims="true"

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

# A claim that is candidate for Selective Disclosure.
# cas.authn.oidc.vc.issuer.credential-configurations.[key].claims.[key].disclosable=true

# Control display settings for this claim.
# cas.authn.oidc.vc.issuer.credential-configurations.[key].claims.[key].display=

# Locale that controls this configuration's display.
# cas.authn.oidc.vc.issuer.credential-configurations.[key].claims.[key].display[0].locale=en-US

# Display name for this configuration.
# cas.authn.oidc.vc.issuer.credential-configurations.[key].claims.[key].display[0].name=

# Whether this claim is mandatory.
# cas.authn.oidc.vc.issuer.credential-configurations.[key].claims.[key].mandatory=

# Lists the signing algorithms supported by the issuer when producing the credential for this configuration.
# cas.authn.oidc.vc.issuer.credential-configurations.[key].credential-signing-alg-values-supported=ES256,RS256

# Lists the supported cryptographic binding methods for this credential.
# cas.authn.oidc.vc.issuer.credential-configurations.[key].cryptographic-binding-methods-supported=jwk

# Control display settings of this credential configuration used in metadata generation.
# cas.authn.oidc.vc.issuer.credential-configurations.[key].display=org.apereo.cas.configuration.model.support.oidc.OidcVerifiableCredentialConfigurationProperties$CredentialConfigurationDisplay@378bd86d

# Background color for this configuration.
# cas.authn.oidc.vc.issuer.credential-configurations.[key].display[0].background-color=

# Description for this configuration.
# cas.authn.oidc.vc.issuer.credential-configurations.[key].display[0].description=My verifiable credential that belongs to my organization

# Locale that controls this configuration's display.
# cas.authn.oidc.vc.issuer.credential-configurations.[key].display[0].locale=en-US

# Logo url.
# cas.authn.oidc.vc.issuer.credential-configurations.[key].display[0].logo=https://apereo.github.io/cas/images/cas_logo.png

# Display name for this configuration.
# cas.authn.oidc.vc.issuer.credential-configurations.[key].display[0].name=My Verifiable Credential

# Text color for this configuration.
# cas.authn.oidc.vc.issuer.credential-configurations.[key].display[0].text-color=

# Defines the credential format issued for this configuration.
# cas.authn.oidc.vc.issuer.credential-configurations.[key].format=OidcVerifiableCredentialConfigurationProperties.CredentialConfigurationFormats.DC_SD_JWT(dc+sd-jwt)

# Lists the signing algorithms supported for proof validation when the wallet submits proof material as part of a credential request.
# cas.authn.oidc.vc.issuer.credential-configurations.[key].proof-signing-alg-values-supported=ES256,RS256

# OAuth scope associated with this credential configuration.
# cas.authn.oidc.vc.issuer.credential-configurations.[key].scope=

# Whether claims should be included in the metadata.
# cas.authn.oidc.vc.metadata.include-claims=true

cas.authn.oidc.vc.issuer.credential-configurations.[key].cryptographic-binding-methods-supported=jwk

org.apereo.cas.configuration.model.support.oidc.OidcVerifiableCredentialConfigurationProperties.

_{Copy Configuration Property

Copied!} _{How can I configure this property?}

Configuration properties can be included and activated using the following strategies.

Note

CAS properties can be specified using the Java configuration property syntax in any and all .properties files:

cas.authn.oidc.vc.issuer.credential-configurations.[key].cryptographic-binding-methods-supported=jwk

CAS properties can be specified using the YAML syntax:

cas: 
  authn: 
    oidc: 
      vc: 
        issuer: 
          credential-configurations: 
            [key]: 
              cryptographic-binding-methods-supported: "jwk"

Note that YAML is very specific about structure and indentation. Be sure to verify the correctness of the final result with your YAML validator of choice.

CAS properties can be passed to the CAS web application as system properties, when the application is launched:

java -Dcas.authn.oidc.vc.issuer.credential-configurations.[key].cryptographic-binding-methods-supported="jwk" -jar build/libs/cas.war

CAS properties can specified as system environment variables before the CAS web application is launched:

export CAS_AUTHN_OIDC_VC_ISSUER_CREDENTIAL_CONFIGURATIONS_[KEY]_CRYPTOGRAPHIC_BINDING_METHODS_SUPPORTED="jwk"

java -jar build/libs/cas.war

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

CAS properties can be passed to the CAS web application as command-line arguments, when the application is launched:

java -jar build/libs/cas.war --cas.authn.oidc.vc.issuer.credential-configurations.[key].cryptographic-binding-methods-supported="jwk"

The above example assumes that the CAS web application is packaged as cas.war with an embedded server container and can be found in the build/libs directory.

This CAS feature is able to accept signing and encryption crypto keys. In most scenarios if keys are not provided, CAS will auto-generate them. The following instructions apply if you wish to manually and beforehand create the signing and encryption keys.

Note that if you are asked to create a JWK of a certain size for the key, you are to use the following set of commands to generate the token:

wget https://raw.githubusercontent.com/apereo/cas/master/etc/jwk-gen.jar
java -jar jwk-gen.jar -t oct -s [size]

The outcome would be similar to:

{
  "kty": "oct",
  "kid": "...",
  "k": "..."
}

The generated value for k needs to be assigned to the relevant CAS settings. Note that keys generated via the above algorithm are processed by CAS using the Advanced Encryption Standard (AES) algorithm which is a specification for the encryption of electronic data established by the U.S. National Institute of Standards and Technology.

CAS takes advantage of Apache Groovy in forms of either embedded or external scripts that allow one to, by default, dynamically build constructs, attributes, access strategies and a lot more. To activate the functionality described here, you may need to prepare CAS to support and integrate with Apache Groovy.

Please review this guide to configure your build.

Configuration Metadata

The collection of configuration properties listed in this section are automatically generated from the CAS source and components that contain the actual field definitions, types, descriptions, modules, etc. This metadata may not always be 100% accurate, or could be lacking details and sufficient explanations.

Be Selective

This section is meant as a guide only. Do NOT copy/paste the entire collection of settings into your CAS configuration; rather pick only the properties that you need. Do NOT enable settings unless you are certain of their purpose and do NOT copy settings into your configuration only to keep them as reference. All these ideas lead to upgrade headaches, maintenance nightmares and premature aging.

YAGNI

Note that for nearly ALL use cases, declaring and configuring properties listed here is sufficient. You should NOT have to explicitly massage a CAS XML/Java/etc configuration file to design an authentication handler, create attribute release policies, etc. CAS at runtime will auto-configure all required changes for you. If you are unsure about the meaning of a given CAS setting, do NOT turn it on without hesitation. Review the codebase or better yet, ask questions to clarify the intended behavior.

Naming Convention

Property names can be specified in very relaxed terms. For instance cas.someProperty, cas.some-property, cas.some_property are all valid names. While all forms are accepted by CAS, there are certain components (in CAS and other frameworks used) whose activation at runtime is conditional on a property value, where this property is required to have been specified in CAS configuration using kebab case. This is both true for properties that are owned by CAS as well as those that might be presented to the system via an external library or framework such as Spring Boot, etc.

Note

Settings and properties that are controlled by the CAS platform directly always begin with the prefix cas. All other settings are controlled and provided to CAS via other underlying frameworks and may have their own schemas and syntax. BE CAREFUL with the distinction. Unrecognized properties are rejected by CAS and/or frameworks upon which CAS depends. This means if you somehow misspell a property definition or fail to adhere to the dot-notation syntax and such, your setting is entirely refused by CAS and likely the feature it controls will never be activated in the way you intend.

Validation

Configuration properties are automatically validated on CAS startup to report issues with configuration binding, especially if defined CAS settings cannot be recognized or validated by the configuration schema. Additional validation processes are also handled via Configuration Metadata and property migrations applied automatically on startup by Spring Boot and family.

Indexed Settings

CAS settings able to accept multiple values are typically documented with an index, such as cas.some.setting[0]=value. The index [0] is meant to be incremented by the adopter to allow for distinct multiple configuration blocks.

Endpoints

The following endpoints are typically involved in the verifiable credential issuance flow.

Issuer Metadata

Publishes issuer capabilities and supported credential configuration metadata.

GET /oidc/.well-known/openid-credential-issuer

This endpoint generally advertises:

The credential issuer identifier.
The credential endpoint.
The nonce endpoint, when supported.
Supported credential configurations.
Supported formats and signing algorithms.
Credential Endpoint

Issues a verifiable credential to the wallet once the access token, proof, and requested credential configuration have been validated.

POST /oidc/oidcVcCredential

This endpoint expects:

A bearer access token.
A requested credential_configuration_id.
A proof object with a nonce as a claim.

The endpoint body is expected as:

{
  credential_configuration_id: "myorg",
  proof: {
    proof_type: "jwt",
    jwt: proof
  }
}

Batch Credential Endpoint

Issues a list of verifiable credentials to the wallet once the access token, proof, and requested credential configurations have been validated.

POST /oidc/oidcVcBatchCredential

This endpoint expects a bearer access token.

…with the following body:

{
  "credential_requests": [
    {
      "credential_configuration_id": "UniversityDegreeCredential",
      "proof": {
        "proof_type": "jwt",
        "jwt": "eyJ0eXAiOiJvcGVuaWQ0dmNpL..."
      }
    }
  ]
}

Nonce Endpoint

Produces a fresh c_nonce that may be used by the wallet in a later proof for the credential request.

POST /oidc/oidcVcNonce

This endpoint typically returns:

c_nonce
c_nonce_expires_in

Credential Offer Endpoint

Exposes a prepared credential offer for a previously-created issuance transaction.

GET /oidc/oidcVcCredentialOffer/{transactionId}

This endpoint does not establish subject identity on its own. Instead, it dereferences a short-lived server-side issuance transaction and returns the corresponding credential offer document.

Trusted Transaction Creation Endpoint

Creates a server-side issuance transaction for a known subject and returns an opaque transaction identifier and a wallet-facing offer URI.

POST /oidc/oidcVcCredentialOfferTransactions

The endpoint body is expected to be:

{
  "principal": "...",
  "credentialConfigurationIds": ["..."]
}

This endpoint is intended for trusted callers such as:

Administrative tools
Internal backend services & APIs
Authenticated CAS user interfaces

This endpoint is protected and should not be exposed as an anonymous wallet-facing API.

Token Endpoint

Exchanges an authorization artifact, such as a pre-authorized code, for an access token that may later be used at the credential endpoint.

POST /oidc/token

When used for verifiable credential issuance, this endpoint may:

Accept the pre-authorized_code grant.
Require a tx_code.
Return a c_nonce.
Produce an access token that is scoped to credential issuance.

Example request:

POST /oidc/token
Content-Type: application/x-www-form-urlencoded

grant_type=urn:ietf:params:oauth:grant-type:pre-authorized_code&
pre-authorized_code=L0Qw0sT6dP5P7l7xM0H2AqQ0g9vM2j5fByuYwQ&
tx_code=TST-1234

Nonce Proof

Proofs are expected to carry a nonce claim. The nonce lets CAS tell whether the wallet’s proof is fresh, instead of a replay. In OIDC4VCI, the wallet sends a proof showing it controls the key the credential should be bound to, and the c_nonce is the primary defense against replay of that proof.

Without a nonce, an attacker who somehow gets hold of a previously valid proof could try to send it again and get a duplicate credential issued to the same key.

In practical terms, the flow is:

The wallet asks CAS for a fresh c_nonce from the nonce endpoint, or receives one from the token endpoint.
The wallet builds its proof and includes that nonce.
CAS checks that the nonce matches one it issued, is still fresh, and has not already been used.
CAS consumes it so the same proof cannot be replayed.

The token endpoint issues the nonce. The credential endpoint enforces it while validating the proof.

Authorization Code Flow

The Authorization Code Flow allows a wallet to obtain authorization to receive one or more verifiable credentials through a standard OAuth 2.0/OpenID Connect authorization process. Unlike the Pre-Authorized Code Flow, where a trusted backend initiates the issuance transaction, the Authorization Code Flow is wallet-driven. The wallet begins by sending an authorization request to the Credential Issuer’s authorization endpoint, requesting one or more credential configurations using the authorization_details parameter. The request may also include the openid scope if the wallet wishes to authenticate the end-user and receive an ID Token as part of the token response. The wallet exchanges the authorization code at the token endpoint to obtain an access token that is specifically authorized for credential issuance.

Pre-Authorized Code Flow

In pre-authorized code flows, CAS or a trusted backend prepares the issuance transaction before the wallet starts the OAuth exchange.

The general flow is:

A trusted caller creates an issuance transaction.
CAS stores the transaction and issues a pre-authorized code.
CAS returns a wallet-facing credential_offer_uri.
The wallet resolves the offer.
The wallet exchanges the pre-authorized code at the token endpoint.
CAS returns an access token, and optionally a c_nonce.
The wallet calls the credential endpoint with the access token and proof.
CAS validates the request and issues the credential.

Credential Signing

After claims are collected and validated, CAS signs the credential using issuer key material.

For JWT-based credential formats, this generally reuses the same signing infrastructure used for ID tokens and other JWT artifacts, while still producing a payload that is specific to the verifiable credential format being issued.