+++ /dev/null
-module HTML
- class Sanitizer
- def sanitize(text, options = {})
- return text unless sanitizeable?(text)
- tokenize(text, options).join
- end
-
- def sanitizeable?(text)
- !(text.nil? || text.empty? || !text.index("<"))
- end
-
- protected
- def tokenize(text, options)
- tokenizer = HTML::Tokenizer.new(text)
- result = []
- while token = tokenizer.next
- node = Node.parse(nil, 0, 0, token, false)
- process_node node, result, options
- end
- result
- end
-
- def process_node(node, result, options)
- result << node.to_s
- end
- end
-
- class FullSanitizer < Sanitizer
- def sanitize(text, options = {})
- result = super
- # strip any comments, and if they have a newline at the end (ie. line with
- # only a comment) strip that too
- result.gsub!(/<!--(.*?)-->[\n]?/m, "") if result
- # Recurse - handle all dirty nested tags
- result == text ? result : sanitize(result, options)
- end
-
- def process_node(node, result, options)
- result << node.to_s if node.class == HTML::Text
- end
- end
-
- class LinkSanitizer < FullSanitizer
- cattr_accessor :included_tags, :instance_writer => false
- self.included_tags = Set.new(%w(a href))
-
- def sanitizeable?(text)
- !(text.nil? || text.empty? || !((text.index("<a") || text.index("<href")) && text.index(">")))
- end
-
- protected
- def process_node(node, result, options)
- result << node.to_s unless node.is_a?(HTML::Tag) && included_tags.include?(node.name)
- end
- end
-
- class WhiteListSanitizer < Sanitizer
- [:protocol_separator, :uri_attributes, :allowed_attributes, :allowed_tags, :allowed_protocols, :bad_tags,
- :allowed_css_properties, :allowed_css_keywords, :shorthand_css_properties].each do |attr|
- class_inheritable_accessor attr, :instance_writer => false
- end
-
- # A regular expression of the valid characters used to separate protocols like
- # the ':' in 'http://foo.com'
- self.protocol_separator = /:|(�*58)|(p)|(%|%)3A/
-
- # Specifies a Set of HTML attributes that can have URIs.
- self.uri_attributes = Set.new(%w(href src cite action longdesc xlink:href lowsrc))
-
- # Specifies a Set of 'bad' tags that the #sanitize helper will remove completely, as opposed
- # to just escaping harmless tags like <font>
- self.bad_tags = Set.new(%w(script))
-
- # Specifies the default Set of tags that the #sanitize helper will allow unscathed.
- self.allowed_tags = Set.new(%w(strong em b i p code pre tt samp kbd var sub
- sup dfn cite big small address hr br div span h1 h2 h3 h4 h5 h6 ul ol li dt dd abbr
- acronym a img blockquote del ins))
-
- # Specifies the default Set of html attributes that the #sanitize helper will leave
- # in the allowed tag.
- self.allowed_attributes = Set.new(%w(href src width height alt cite datetime title class name xml:lang abbr))
-
- # Specifies the default Set of acceptable css properties that #sanitize and #sanitize_css will accept.
- self.allowed_protocols = Set.new(%w(ed2k ftp http https irc mailto news gopher nntp telnet webcal xmpp callto
- feed svn urn aim rsync tag ssh sftp rtsp afs))
-
- # Specifies the default Set of acceptable css keywords that #sanitize and #sanitize_css will accept.
- self.allowed_css_properties = Set.new(%w(azimuth background-color border-bottom-color border-collapse
- border-color border-left-color border-right-color border-top-color clear color cursor direction display
- elevation float font font-family font-size font-style font-variant font-weight height letter-spacing line-height
- overflow pause pause-after pause-before pitch pitch-range richness speak speak-header speak-numeral speak-punctuation
- speech-rate stress text-align text-decoration text-indent unicode-bidi vertical-align voice-family volume white-space
- width))
-
- # Specifies the default Set of acceptable css keywords that #sanitize and #sanitize_css will accept.
- self.allowed_css_keywords = Set.new(%w(auto aqua black block blue bold both bottom brown center
- collapse dashed dotted fuchsia gray green !important italic left lime maroon medium none navy normal
- nowrap olive pointer purple red right solid silver teal top transparent underline white yellow))
-
- # Specifies the default Set of allowed shorthand css properties for the #sanitize and #sanitize_css helpers.
- self.shorthand_css_properties = Set.new(%w(background border margin padding))
-
- # Sanitizes a block of css code. Used by #sanitize when it comes across a style attribute
- def sanitize_css(style)
- # disallow urls
- style = style.to_s.gsub(/url\s*\(\s*[^\s)]+?\s*\)\s*/, ' ')
-
- # gauntlet
- if style !~ /^([:,;#%.\sa-zA-Z0-9!]|\w-\w|\'[\s\w]+\'|\"[\s\w]+\"|\([\d,\s]+\))*$/ ||
- style !~ /^(\s*[-\w]+\s*:\s*[^:;]*(;|$)\s*)*$/
- return ''
- end
-
- clean = []
- style.scan(/([-\w]+)\s*:\s*([^:;]*)/) do |prop,val|
- if allowed_css_properties.include?(prop.downcase)
- clean << prop + ': ' + val + ';'
- elsif shorthand_css_properties.include?(prop.split('-')[0].downcase)
- unless val.split().any? do |keyword|
- !allowed_css_keywords.include?(keyword) &&
- keyword !~ /^(#[0-9a-f]+|rgb\(\d+%?,\d*%?,?\d*%?\)?|\d{0,2}\.?\d{0,2}(cm|em|ex|in|mm|pc|pt|px|%|,|\))?)$/
- end
- clean << prop + ': ' + val + ';'
- end
- end
- end
- clean.join(' ')
- end
-
- protected
- def tokenize(text, options)
- options[:parent] = []
- options[:attributes] ||= allowed_attributes
- options[:tags] ||= allowed_tags
- super
- end
-
- def process_node(node, result, options)
- result << case node
- when HTML::Tag
- if node.closing == :close
- options[:parent].shift
- else
- options[:parent].unshift node.name
- end
-
- process_attributes_for node, options
-
- options[:tags].include?(node.name) ? node : nil
- else
- bad_tags.include?(options[:parent].first) ? nil : node.to_s.gsub(/</, "<")
- end
- end
-
- def process_attributes_for(node, options)
- return unless node.attributes
- node.attributes.keys.each do |attr_name|
- value = node.attributes[attr_name].to_s
-
- if !options[:attributes].include?(attr_name) || contains_bad_protocols?(attr_name, value)
- node.attributes.delete(attr_name)
- else
- node.attributes[attr_name] = attr_name == 'style' ? sanitize_css(value) : CGI::escapeHTML(CGI::unescapeHTML(value))
- end
- end
- end
-
- def contains_bad_protocols?(attr_name, value)
- uri_attributes.include?(attr_name) &&
- (value =~ /(^[^\/:]*):|(�*58)|(p)|(%|%)3A/ && !allowed_protocols.include?(value.split(protocol_separator).first))
- end
- end
-end
projects / feedcatcher.git / blobdiff