discourse/lib/content_security_policy/extension.rb

99 lines
2.6 KiB
Ruby

# frozen_string_literal: true
class ContentSecurityPolicy
module Extension
extend self
def site_setting_extension
{ script_src: SiteSetting.content_security_policy_script_src.split("|") }
end
def plugin_extensions
[].tap do |extensions|
Discourse.plugins.each do |plugin|
extensions.concat(plugin.csp_extensions) if plugin.enabled?
end
end
end
THEME_SETTING = "extend_content_security_policy"
def theme_extensions(theme_id)
key = "theme_extensions_#{theme_id}"
cache.defer_get_set(key) { find_theme_extensions(theme_id) }
end
def clear_theme_extensions_cache!
cache.clear
end
private
def cache
@cache ||= DistributedCache.new("csp_extensions")
end
def find_theme_extensions(theme_id)
extensions = []
theme_ids = Theme.transform_ids(theme_id)
Theme
.where(id: theme_ids)
.find_each do |theme|
theme.cached_settings.each do |setting, value|
extensions << build_theme_extension(value.split("|")) if setting.to_s == THEME_SETTING
end
end
extensions << build_theme_extension(
ThemeModifierHelper.new(theme_ids: theme_ids).csp_extensions,
)
html_fields =
ThemeField.where(
theme_id: theme_ids,
target_id: ThemeField.basic_targets.map { |target| Theme.targets[target.to_sym] },
name: ThemeField.html_fields,
)
auto_script_src_extension = { script_src: [] }
html_fields.each(&:ensure_baked!)
doc = html_fields.map(&:value_baked).join("\n")
Nokogiri::HTML5
.fragment(doc)
.css("script[src]")
.each do |node|
src = node["src"]
uri = URI(src)
next if GlobalSetting.cdn_url && src.starts_with?(GlobalSetting.cdn_url) # Ignore CDN urls (theme-javascripts)
next if uri.host.nil? # Ignore same-domain scripts (theme-javascripts)
next if uri.path.nil? # Ignore raw hosts
uri.query = nil # CSP should not include query part of url
uri_string = uri.to_s.sub(%r{\A//}, "") # Protocol-less CSP should not have // at beginning of URL
auto_script_src_extension[:script_src] << uri_string
rescue URI::Error
# Ignore invalid URI
end
extensions << auto_script_src_extension
extensions
end
def build_theme_extension(entries)
{}.tap do |extension|
entries.each do |entry|
directive, source = entry.split(":", 2).map(&:strip)
extension[directive] ||= []
extension[directive] << source
end
end
end
end
end