discourse/app/controllers/directory_items_controller.rb
Alan Guo Xiang Tan bfc3132bb2
SECURITY: Impose a upper bound on limit params in various controllers
What is the problem here?

In multiple controllers, we are accepting a `limit` params but do not
impose any upper bound on the values being accepted. Without an upper
bound, we may be allowing arbituary users from generating DB queries
which may end up exhausing the resources on the server.

What is the fix here?

A new `fetch_limit_from_params` helper method is introduced in
`ApplicationController` that can be used by controller actions to safely
get the limit from the params as a default limit and maximum limit has
to be set. When an invalid limit params is encountered, the server will
respond with the 400 response code.
2023-07-28 12:53:46 +01:00

151 lines
5.3 KiB
Ruby

# frozen_string_literal: true
class DirectoryItemsController < ApplicationController
PAGE_SIZE = 50
before_action :set_groups_exclusion, if: -> { params[:exclude_groups].present? }
def index
unless SiteSetting.enable_user_directory?
raise Discourse::InvalidAccess.new(:enable_user_directory)
end
period = params.require(:period)
period_type = DirectoryItem.period_types[period.to_sym]
raise Discourse::InvalidAccess.new(:period_type) unless period_type
result = DirectoryItem.where(period_type: period_type).includes(user: :user_custom_fields)
if params[:group]
group = Group.find_by(name: params[:group])
raise Discourse::InvalidParameters.new(:group) if group.blank?
guardian.ensure_can_see!(group)
guardian.ensure_can_see_group_members!(group)
result = result.includes(user: :groups).where(users: { groups: { id: group.id } })
else
result = result.includes(user: :primary_group)
end
result = apply_exclude_groups_filter(result)
if params[:exclude_usernames]
result =
result
.references(:user)
.where.not(users: { username: params[:exclude_usernames].split(",") })
end
order = params[:order] || DirectoryColumn.automatic_column_names.first
dir = params[:asc] ? "ASC" : "DESC"
active_directory_column_names = DirectoryColumn.active_column_names
if active_directory_column_names.include?(order.to_sym)
result = result.order("directory_items.#{order} #{dir}, directory_items.id")
elsif params[:order] === "username"
result = result.order("users.#{order} #{dir}, directory_items.id")
else
# Ordering by user field value
user_field = UserField.find_by(name: params[:order])
if user_field
result =
result
.references(:user)
.joins(
"LEFT OUTER JOIN user_custom_fields ON user_custom_fields.user_id = users.id AND user_custom_fields.name = 'user_field_#{user_field.id}'",
)
.order(
"user_custom_fields.name = 'user_field_#{user_field.id}' ASC, user_custom_fields.value #{dir}",
)
end
end
result = result.includes(:user_stat) if period_type == DirectoryItem.period_types[:all]
page = params[:page].to_i
user_ids = nil
if params[:name].present?
user_ids = UserSearch.new(params[:name], include_staged_users: true).search.pluck(:id)
if user_ids.present?
# Add the current user if we have at least one other match
user_ids << current_user.id if current_user && result.dup.where(user_id: user_ids).exists?
result = result.where(user_id: user_ids)
else
result = result.where("false")
end
end
if params[:username]
user_id = User.where(username_lower: params[:username].to_s.downcase).pick(:id)
if user_id
result = result.where(user_id: user_id)
else
result = result.where("false")
end
end
limit = fetch_limit_from_params(default: PAGE_SIZE, max: PAGE_SIZE)
result_count = result.count
result = result.limit(limit).offset(limit * page).to_a
more_params = params.slice(:period, :order, :asc, :group, :user_field_ids).permit!
more_params[:page] = page + 1
load_more_uri = URI.parse(directory_items_path(more_params))
load_more_directory_items_json = "#{load_more_uri.path}.json?#{load_more_uri.query}"
# Put yourself at the top of the first page
if result.present? && current_user.present? && page == 0 && !params[:group].present?
position = result.index { |r| r.user_id == current_user.id }
# Don't show the record unless you're not in the top positions already
if (position || 10) >= 10
unless @users_in_exclude_groups&.include?(current_user.id)
your_item = DirectoryItem.where(period_type: period_type, user_id: current_user.id).first
result.insert(0, your_item) if your_item
end
end
end
last_updated_at = DirectoryItem.last_updated_at(period_type)
serializer_opts = {}
if params[:user_field_ids]
serializer_opts[:user_custom_field_map] = {}
user_field_ids = params[:user_field_ids]&.split("|")&.map(&:to_i)
user_field_ids.each do |user_field_id|
serializer_opts[:user_custom_field_map][
"#{User::USER_FIELD_PREFIX}#{user_field_id}"
] = user_field_id
end
end
if params[:plugin_column_ids]
serializer_opts[:plugin_column_ids] = params[:plugin_column_ids]&.split("|")&.map(&:to_i)
end
serializer_opts[:attributes] = active_directory_column_names
serialized = serialize_data(result, DirectoryItemSerializer, serializer_opts)
render_json_dump(
directory_items: serialized,
meta: {
last_updated_at: last_updated_at,
total_rows_directory_items: result_count,
load_more_directory_items: load_more_directory_items_json,
},
)
end
private
def set_groups_exclusion
@exclude_group_names = params[:exclude_groups].split("|")
@exclude_group_ids = Group.where(name: @exclude_group_names).pluck(:id)
@users_in_exclude_groups = GroupUser.where(group_id: @exclude_group_ids).pluck(:user_id)
end
def apply_exclude_groups_filter(result)
result = result.where.not(user_id: @users_in_exclude_groups) if params[:exclude_groups]
result
end
end