62 lines
1.6 KiB
Ruby
62 lines
1.6 KiB
Ruby
# frozen_string_literal: true
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require_dependency 'gitlab/utils'
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module Gitlab
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module Utils
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module SanitizeNodeLink
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UNSAFE_PROTOCOLS = %w(data javascript vbscript).freeze
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ATTRS_TO_SANITIZE = %w(href src data-src).freeze
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def remove_unsafe_links(env, remove_invalid_links: true)
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node = env[:node]
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sanitize_node(node: node, remove_invalid_links: remove_invalid_links)
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# HTML entities such as <video></video> have scannable attrs in
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# children elements, which also need to be sanitized.
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#
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node.children.each do |child_node|
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sanitize_node(node: child_node, remove_invalid_links: remove_invalid_links)
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end
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end
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# Remove all invalid scheme characters before checking against the
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# list of unsafe protocols.
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#
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# See https://tools.ietf.org/html/rfc3986#section-3.1
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#
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def safe_protocol?(scheme)
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return false unless scheme
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scheme = scheme
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.strip
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.downcase
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.gsub(/[^A-Za-z\+\.\-]+/, '')
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UNSAFE_PROTOCOLS.none?(scheme)
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end
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private
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def sanitize_node(node:, remove_invalid_links: true)
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ATTRS_TO_SANITIZE.each do |attr|
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next unless node.has_attribute?(attr)
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begin
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node[attr] = node[attr].strip
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uri = Addressable::URI.parse(node[attr])
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next unless uri.scheme
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next if safe_protocol?(uri.scheme)
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node.remove_attribute(attr)
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rescue Addressable::URI::InvalidURIError
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node.remove_attribute(attr) if remove_invalid_links
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end
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end
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end
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end
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end
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end
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