JBoss Identity  supports SAML2 Metadata profile.

Configure the metadata profile at the IDP

Create a web application for the IDP metadata.  In the web.xml, the following should be present:

<?xml version="1.0" encoding="ISO-8859-1"?>
<web-app xmlns="http://java.sun.com/xml/ns/javaee"
   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
   version="2.5">

  <display-name>IDP Metadata</display-name>
  <description>
    Metadata for the IDP
  </description>

  <servlet>
    <servlet-name>metadata</servlet-name>
    <servlet-class>org.jboss.identity.federation.bindings.servlets.MetadataServlet</servlet-class>
  </servlet>

  <servlet-mapping>
    <servlet-name>metadata</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>

</web-app>

In the WEB-INF folder, you will need a jboss-idfed.xml with

<JBossIDP xmlns="urn:jboss:identity-federation:config:1.0" 
          AssertionValidity="20000"
          RoleGenerator="somefqn"
          Encrypt="true">
 <IdentityURL>http://localhost:8080/idp</IdentityURL>
 <Trust>
   <Domains>localhost,jboss.com,jboss.org</Domains>
 </Trust>
 <KeyProvider ClassName="org.jboss.identity.federation.bindings.tomcat.KeyStoreKeyManager">
    <Auth Key="KeyStoreURL" Value="jbid_test_keystore.jks" />
    <Auth Key="KeyStorePass" Value="store123" />
    <Auth Key="SigningKeyPass" Value="test123" />
    <Auth Key="SigningKeyAlias" Value="servercert" />
    <SigningAlias>servercert</SigningAlias>
    <ValidatingAlias Key="localhost" Value="servercert"/>
    <ValidatingAlias Key="127.0.0.1" Value="servercert"/>
 </KeyProvider>

 <MetaDataProvider ClassName="org.jboss.identity.federation.bindings.providers.FileBasedEntityMetadataProvider">
  <Option Key="FileName" Value="WEB-INF/idp-metadata.xml"/>
 </MetaDataProvider>  
</JBossIDP>

Both the Trust and KeyProvider elements are optional.

You will need the MetaDataProvider element.

You will need to provide the entire metadata xml in idp-metadata.xml in the WEB-INF folder of your web  app.

An example:

<EntityDescriptor xmlns="urn:oasis:names:tc:SAML:2.0:metadata"
xmlns:saml="urn:oasis:names:tc:SAML:2.0:assertion"
xmlns:ds="http://www.w3.org/2000/09/xmldsig#"
entityID="https://IdentityProvider.com/SAML"> 
<IDPSSODescriptor WantAuthnRequestsSigned="true"
protocolSupportEnumeration="urn:oasis:names:tc:SAML:2.0:protocol"> 

<ArtifactResolutionService isDefault="true" index="0"
Binding="urn:oasis:names:tc:SAML:2.0:bindings:SOAP"
Location="https://IdentityProvider.com/SAML/Artifact"/>
<SingleLogoutService
Binding="urn:oasis:names:tc:SAML:2.0:bindings:SOAP"
Location="https://IdentityProvider.com/SAML/SLO/SOAP"/>
<SingleLogoutService
Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-Redirect"
Location="https://IdentityProvider.com/SAML/SLO/Browser"
ResponseLocation="https://IdentityProvider.com/SAML/SLO/Response"/> 
<NameIDFormat>
urn:oasis:names:tc:SAML:1.1:nameid-format:X509SubjectName
</NameIDFormat>
<NameIDFormat>
urn:oasis:names:tc:SAML:2.0:nameid-format:persistent
</NameIDFormat>
<NameIDFormat>
urn:oasis:names:tc:SAML:2.0:nameid-format:transient
</NameIDFormat>
<SingleSignOnService
Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-Redirect"
Location="https://IdentityProvider.com/SAML/SSO/Browser"/>
<SingleSignOnService
Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-POST"
Location="https://IdentityProvider.com/SAML/SSO/Browser"/>
<saml:Attribute
NameFormat="urn:oasis:names:tc:SAML:2.0:attrname-format:uri"
Name="urn:oid:1.3.6.1.4.1.5923.1.1.1.6"
FriendlyName="eduPersonPrincipalName">
</saml:Attribute>
<saml:Attribute
NameFormat="urn:oasis:names:tc:SAML:2.0:attrname-format:uri"
Name="urn:oid:1.3.6.1.4.1.5923.1.1.1.1"
FriendlyName="eduPersonAffiliation">
<saml:AttributeValue>member</saml:AttributeValue>
<saml:AttributeValue>student</saml:AttributeValue>
<saml:AttributeValue>faculty</saml:AttributeValue>
<saml:AttributeValue>employee</saml:AttributeValue>
<saml:AttributeValue>staff</saml:AttributeValue>
</saml:Attribute>
</IDPSSODescriptor>
</EntityDescriptor>

Configuring the SP for metadata

It is similar to the IDP configuration.  You will need to maybe create a sp-metadata.xml and appropriately configure the jboss-idfed.xml

General Notes

1. The implementation is a servlet that serves standard metadata (that does not change often)
2. By default, the metadata provider is a file based provider that just serves a standard file that you have created (idp-metadata.xml or sp-metadata.xml).  The name of the file can be anything as long as the jboss-idfed.xml is updated.