test/jdk/sun/security/provider/PolicyFile/SelfExpansion.policy

grant {
    permission javax.security.auth.AuthPermission "modifyPrincipals";
    permission javax.security.auth.AuthPermission "modifyPrivateCredentials";
    permission javax.security.auth.AuthPermission "doAsPrivileged";
    permission javax.security.auth.AuthPermission "getSubject";
};

grant principal javax.security.auth.x500.X500Principal "CN=test" {
    permission javax.security.auth.PrivateCredentialPermission "java.lang.String ${{self}}", "read";
};