使用设备保护活动存储

Question

使用设计 gem 对应用程序的所有用户进行身份验证。我正在尝试实施活动存储。

假设所有用户在访问应用程序后都必须进行身份验证：

class ApplicationController < ActionController::Base
  before_action :authenticate_user!

...
end

如何保护 Active Storage 生成的路由？

URL 的上传文件无需先进行身份验证即可访问。未经身份验证的用户可以获得 Active Storage 生成的文件 url。

Answer 1

这不是一个完整的答案，而是一个起点：

要点：您需要覆盖重定向控制器。

docs for activestorage/app/controllers/active_storage/blobs_controller.rb 说：

If you need to enforce access protection beyond the security-through-obscurity factor of the signed blob references, you'll need to implement your own authenticated redirection controller.

此外，如果您打算使用预览 docs for activestorage/app/models/active_storage/blob/representable.rb 说

Active Storage provides one [controller action for previews], but you may want to create your own (for example, if you need authentication).

您还可以在 this rails github issue

中找到一些相关信息

更新： 这是一个最小的例子，它“应该”在使用 devise gem.

时防止未经授权访问重定向。

url，用户登录后将被重定向到，然后是如何保护的，我想这又是另一回事了。默认情况下，它们会在 5 分钟后过期，但这可以设置为更短的时间，例如 10 秒（如果您将下面示例中的第 6 行替换为 expires_in 10.seconds）

使用以下代码创建文件 app/controllers/active_storage/blobs_controller.rb：

class ActiveStorage::BlobsController < ActiveStorage::BaseController
  before_action :authenticate_user!
  include ActiveStorage::SetBlob

  def show
    expires_in ActiveStorage::Blob.service.url_expires_in
    redirect_to @blob.service_url(disposition: params[:disposition])
  end
end

请注意，与 original code 唯一不同的是添加了第二行

before_action :authenticate_user!

更新二：

您可以在 ActiveStorage::RepresentationsController 和 ActiveStorage::BlobsController 中包含一个问题，以便为 ActiveStorage

启用 devise 身份验证

要点见 https://gist.github.com/dommmel/4e41b204b97238e9aaf35939ae8e1666 也包含在这里：

# Rails controller concern to enable Devise authentication for ActiveStorage.
# Put it in +app/controllers/concerns/blob_authenticatable.rb+ and include it when overriding
# +ActiveStorage::BlobsController+ and +ActiveStorage::RepresentationsController+.
# 
# Optional configuration:
# 
# Set the model that includes devise's database_authenticatable.
# Defaults to Devise.default_scope which defaults to the first
# devise role declared in your routes (usually :user)
#
#   blob_authenticatable resource: :admin
#   
# To specify how to determine if the current_user is allowed to access the 
# blob, override the can_access_blob? method
#   
# Minimal example:
# 
#   class ActiveStorage::BlobsController < ActiveStorage::BaseController
#     include ActiveStorage::SetBlob
#     include AdminOrUserAuthenticatable
#     
#     def show
#       expires_in ActiveStorage::Blob.service.url_expires_in
#       redirect_to @blob.service_url(disposition: params[:disposition])
#     end
#   end
# 
# Complete example:
# 
#   class ActiveStorage::RepresentationsController < ActiveStorage::BaseController
#     include ActiveStorage::SetBlob
#     include AdminOrUserAuthenticatable
# 
#     blob_authenticatable resource: :admin
#
#     def show
#       expires_in ActiveStorage::Blob.service.url_expires_in
#       redirect_to @blob.representation(params[:variation_key]).processed.service_url(disposition: params[:disposition])
#     end
#     
#     private
#
#       def can_access_blob?(current_user)
#         @blob.attachments.map(&:record).all? { |record| record.user == current_user }
#       end
#   end

module BlobAuthenticatable
  extend ActiveSupport::Concern

  included do
    around_action :wrap_in_authentication
  end
  
  module ClassMethods
    def auth_resource
      @auth_resource || Devise.default_scope
    end

    private

      def blob_authenticatable(resource:)
        @auth_resource = resource
      end
  end

  private

    def wrap_in_authentication
      is_signed_in_and_authorized = send("#{self.class.auth_resource}_signed_in?") \
        & can_access_blob?(send("current_#{self.class.auth_resource}"))

      if is_signed_in_and_authorized
        yield
      else
        head :unauthorized
      end
    end

    def can_access_blob?(_user)
      true
    end
end

Answer 2

如果要对活动存储提供的所有端点实施身份验证，可以基于original implementation覆盖ActiveStorage::BaseController：

# app/controllers/active_storage/base_controller.rb

# frozen_string_literal: true

# The base class for all Active Storage controllers.
class ActiveStorage::BaseController < ActionController::Base
  before_action :authenticate_user!
  include ActiveStorage::SetCurrent

  protect_from_forgery with: :exception
end

使用设备保护活动存储

Secure active storage with devise

ruby-on-rails

rails-activestorage