Acegi Security：如何向匿名用户添加另一个GrantedAuthority到身份验证

Question

我为用户提供了带有访问密钥的特殊URL。与简单的匿名用户相比，通过此特殊网址访问公共页面的用户应该能够看到一些额外的数据。

我想根据请求中提供的参数给匿名用户一些额外的角色，这样我就可以在我的模板中做到这样的事情：

<@sec.authorize ifAnyGranted="ROLE_ADMIN, ROLE_USER, ROLE_INVITED_VISITOR">
...some additional stuff for invited user to see
</@sec.authorize>

目前我正在实现Spring的 OncePerRequestfilter ：

protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain chain) throws ServletException, IOException {
    if (null != request.getParameter("accessKey")) {
        if(isValid(request.getParameter("accessKey"))) {
            Authentication auth = SecurityContextHolder.getContext().getAuthentication();
            //how do i add additional roles to authenticated (potentially anonymous) user?
        }
    }
}

Answer 1

为什么不创建一个委托给原文的包装类，而是添加几个额外的GrantedAuthorities：

public class AuthenticationWrapper implements Authentication
{
   private Authentication original;
   private GrantedAuthority[] extraRoles;

   public AuthenticationWrapper( Authentication original, GrantedAuthority[] extraRoles )
   {
      this.original = original;
      this.extraRoles = extraRoles;
   }

   public GrantedAuthority[] getAuthorities()
   {
      GrantedAuthority[] originalRoles = original.getAuthorities();
      GrantedAuthority[]  roles = new GrantedAuthority[originalRoles.length + extraRoles.length];
      System.arraycopy( originalRoles, 0, roles, 0, originalRoles.length );
      System.arraycopy( extraRoles, 0, roles, originalRoles.length, extraRoles.length );
      return roles;
   }

   public String getName() { return original.getName(); }
   public Object getCredentials() { return original.getCredentials(); }
   public Object getDetails() { return original.getDetails(); }   
   public Object getPrincipal() { return original.getPrincipal(); }
   public boolean isAuthenticated() { return original.isAuthenticated(); }
   public void setAuthenticated( boolean isAuthenticated ) throws IllegalArgumentException
   {
      original.setAuthenticated( isAuthenticated );
   }  
}

然后在您的过滤器中执行此操作：

Authentication auth = SecurityContextHolder.getContext().getAuthentication();
GrantedAuthority extraRoles = new GrantedAuthority[2];
extraRoles[0] = new GrantedAuthorityImpl( "Role X" );
extraRoles[1] = new GrantedAuthorityImpl( "Role Y" );
AuthenticationWrapper wrapper = new AuthenticationWrapper( auth, extraRoles );
SecurityContextHolder.getContext().setAuthentication( wrapper );

现在，您的版本将使用额外角色替换身份验证。注意您可能必须处理尚未验证身份验证的情况，因此其getAuthorities（）返回null。 （包装器实现当前假定它总是从其包装的身份验证中获取非空数组）