diff options
Diffstat (limited to 'lib/banzai/filter/sanitization_filter.rb')
| -rw-r--r-- | lib/banzai/filter/sanitization_filter.rb | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/lib/banzai/filter/sanitization_filter.rb b/lib/banzai/filter/sanitization_filter.rb index 04ddfe53ed6..e8011519608 100644 --- a/lib/banzai/filter/sanitization_filter.rb +++ b/lib/banzai/filter/sanitization_filter.rb @@ -7,6 +7,8 @@ module Banzai # # Extends HTML::Pipeline::SanitizationFilter with a custom whitelist. class SanitizationFilter < HTML::Pipeline::SanitizationFilter + UNSAFE_PROTOCOLS = %w(data javascript vbscript).freeze + def whitelist whitelist = super @@ -43,8 +45,8 @@ module Banzai # Allow any protocol in `a` elements... whitelist[:protocols].delete('a') - # ...but then remove links with the `javascript` protocol - whitelist[:transformers].push(remove_javascript_links) + # ...but then remove links with unsafe protocols + whitelist[:transformers].push(remove_unsafe_links) # Remove `rel` attribute from `a` elements whitelist[:transformers].push(remove_rel) @@ -55,14 +57,19 @@ module Banzai whitelist end - def remove_javascript_links + def remove_unsafe_links lambda do |env| node = env[:node] return unless node.name == 'a' return unless node.has_attribute?('href') - if node['href'].start_with?('javascript', ':javascript') + begin + uri = Addressable::URI.parse(node['href']) + uri.scheme.strip! if uri.scheme + + node.remove_attribute('href') if UNSAFE_PROTOCOLS.include?(uri.scheme) + rescue Addressable::URI::InvalidURIError node.remove_attribute('href') end end |