XML Watermarking

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XML Watermarking Information Hiding
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Markup Language

• SGML (Standard Generalized Markup Language)
• XML (Extensible Markup Language)
• HTML (HyperText Markup Language)
• XHTML

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Publishing Information in WWW
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Publishing Information in WWW
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XML Document
Corresponding Watermarking and information
hiding techniques can be employed

• XML element type
• text
• image
• Video
• Audio
• executive codes

Can we use its own information to do watermarking
or information hiding?
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Known content-based technique

• Change font size, color
• Append white spaces at the end of a line
• 0-space (x0020)
• 1-tab (x0009)

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Shortcomings

• white spaces at the end of a line
• Increase page size
• Layout might be changed
• Detect very easily by selection

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Specification

• Element (Entity)
• ltname attribute1 attributengt contents lt/name gt
• ltname attribute1 attributengt lt/name gt
• ltname attribute1 attributengt
• Attribute
• namevalue
• Example
• ltfont face"Verdana" size"4" color"FFFF00"gtStud
  ent Number lt/fontgt

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Properties of markup labels

• Property 1 Element and attribute names are
  case-insensitive
• ltfont face"Verdana" size"4" color"FFFF00"gtStud
  ent Number lt/fontgt
• ltFont face"Verdana" size"4" color"FFFF00"gtStud
  ent Number lt/fontgt
• ltfont face"Verdana" size"4" color"FFFF00"gtStud
  ent Number lt/Fontgt
• ltFont face"Verdana" size"4" color"FFFF00"gtStud
  ent Number lt/Fontgt

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Properties of markup labels

• Property 2 Attributes are order-insensitive
• ltfont face"Verdana" size"4" color"FFFF00"gtStud
  ent Number lt/fontgt
• ltfont size"4" face"Verdana" color"FFFF00"gtStud
  ent Number lt/fontgt

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Pair attributes technique

• pair attributes order (Corinna John)
• key attribute, corresponding attribute
• key / corresponding (1) corresponding/key (0)
• ltfont face"Verdana" size"4" color"FFFF00"gtStud
  ent Namelt/fontgt
• ltfont size"4" face"Verdana" color"FFFF00"gtStud
  ent Namelt/Fontgt
• key / corresponding table
• size, detect difficultly

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Attributes permutation technique

• equivalent attributes permutation
• ltfont face"Verdana" size"4" color"FFFF00"gtStud
  ent Namelt/fontgt
• ltfont face"Verdana" color"FFFF00"
  size"4"gtStudent Namelt/fontgt
• ltfont size"4" face"Verdana" color"FFFF00"gtStud
  ent Namelt/fontgt
• ltfont size"4" color"FFFF00" face"Verdana"
  gtStudent Namelt/fontgt
• ltfont color"FFFF00" face"Verdana" size"4"
  gtStudent Namelt/fontgt
• ltfont color"FFFF00" size"4" face"Verdana"
  gtStudent Namelt/fontgt
• lexicographic (alphabetic) order f precedes a
  permutation g iff f(k)ltg(k) for the minimum
  value of k such that f(k)ltgtg(k).

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Attributes permutation technique

• Generating attributes permutations in
  lexicographical order
• ltfont color"FFFF00" face"Verdana" size"4"
  gtStudent Namelt/fontgt
• ltfont color"FFFF00" size"4" face"Verdana"
  gtStudent Namelt/fontgt
• ltfont face"Verdana" color"FFFF00"
  size"4"gtStudent Namelt/fontgt
• ltfont face"Verdana" size"4" color"FFFF00"gtStud
  ent Namelt/fontgt
• ltfont size"4" face"Verdana" color"FFFF00"gtStud
  ent Namelt/fontgt
• ltfont size"4" color"FFFF00" face"Verdana"
  gtStudent Namelt/fontgt
• attributes permutations ?? order numbers
• color face size 0
• color size face 1
• face color size 2
• face size color 3
• size face color 4
• Size color face 5

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Attributes permutation technique

• If the number of attributes of an element gt2, it
  may be used to embed hidden information or
  watermark
• Let be the elements, whose number of
  attributes , in a web page, the
  embedded capacity is

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Embedded capacity example
Name of web page Capacity (bytes)
www.163.com 48
www.sina.com.cn 279
www.sohu.com.cn 338
www.microsfot.com 15
www.ebay.com 78
www.yahoo.com 33
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Perceivability

• Can not perceive when browse the page
• Hard to perceive through reading the source codes

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Robust or resistant against editing

• Contents can be changed

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Robust or resistant against editing

• Font, size, color can be changed

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Security

• attributes permutations ?? order numbers
• color face size 0
• color size face 1
• face color size 2
• face size color 3
• size face color 4
• Size color face 5
• Apply hash to concatenation of attributes and key
  to get order number

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Performance comparison
Type Size change Perceivable by Perceivable by Capacity (bit) Extra payload
Type Size change view code Capacity (bit) Extra payload
White space Y easy easy Page lines N
Case change N N easy Tags N
Attribute pair N N hard Pair table
Equivalent attributes N N hard N
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Other potential properties

• String delimiters
• namevalue
• namevalue
• White Space Between the Elements Name and the
  First Attribute
• ltfont faceverdana size3gt
• ltfont faceverdana size3gt
• White Space Between Attributes
• ltfont faceverdana size3gt
• ltfont faceverdana size3gt

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Other potential properties

• White Space after
• ltfont faceverdana size3gt
• ltfont face verdana size3gt
• White Space Between Elements
• lttdgtcon1lt/tdgtlttdgtcon2lt/tdgt
• lttdgtcon1lt/tdgt lttdgtcon2lt/tdgt

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Other potential properties

• The default value of an attribute
• ltfont faceverdana size3gt
• ltfont faceverdanagt

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Current progress

• Introduce insignificant attributes
• ltfont faceverdanagt
• ltfont faceverdana xyzabcdgt
• Break through the capacity bottle neck
• Web page watermarking
• Text watermarking

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Our focus on watermarking

• Text content security
• Funded by NSFC Key Project 60736016
• Funded by NSFC 60373062
• Software watermarking
• Funded by NSFC 60573045
• Wireless sensor network security
• Funded by 973 Project 2006CB303000
• Funded by NSFC 60873198
• Steganalysis
• Funded by 115 Project

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????0731-8821341,13875971258 Emailsunnudt_at_163.co
m http//nisl.hnu.cn/
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• HyperText Markup Language (HTML), version 4.0,
  the publishing language of the World Wide Web
• Recall that in HTML, element and attribute names
  are case-insensitive the convention is meant to
  encourage readability.
• Element and attribute names in this document have
  been marked up and may be rendered specially by
  some user agents.
• http//www.w3.org/TR/1998/REC-html40-19980424/abou
  t.htmlh-1.2.1

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http//www.w3.org/TR/html/xhtml

• HTML 4 HTML4 is an SGML (Standard Generalized
  Markup Language) application conforming to
  International Standard ISO 8879, and is widely
  regarded as the standard publishing language of
  the World Wide Web.
• SGML is a language for describing markup
  languages, particularly those used in electronic
  document exchange, document management, and
  document publishing. HTML is an example of a
  language defined in SGML.
• SGML has been around since the middle 1980's and
  has remained quite stable. Much of this stability
  stems from the fact that the language is both
  feature-rich and flexible. This flexibility,
  however, comes at a price, and that price is a
  level of complexity that has inhibited its
  adoption in a diversity of environments,
  including the World Wide Web.
• HTML, as originally conceived, was to be a
  language for the exchange of scientific and other
  technical documents, suitable for use by
  non-document specialists. HTML addressed the
  problem of SGML complexity by specifying a small
  set of structural and semantic tags suitable for
  authoring relatively simple documents. In
  addition to simplifying the document structure,
  HTML added support for hypertext. Multimedia
  capabilities were added later.
• In a remarkably short space of time, HTML became
  wildly popular and rapidly outgrew its original
  purpose. Since HTML's inception, there has been
  rapid invention of new elements for use within
  HTML (as a standard) and for adapting HTML to
  vertical, highly specialized, markets. This
  plethora of new elements has led to
  interoperability problems for documents across
  different platforms.

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• XML is the shorthand name for Extensible Markup
  Language XML.
• XML was conceived as a means of regaining the
  power and flexibility of SGML without most of its
  complexity. Although a restricted form of SGML,
  XML nonetheless preserves most of SGML's power
  and richness, and yet still retains all of SGML's
  commonly used features.
• While retaining these beneficial features, XML
  removes many of the more complex features of SGML
  that make the authoring and design of suitable
  software both difficult and costly.

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• XHTML is a family of current and future document
  types and modules that reproduce, subset, and
  extend HTML 4 HTML4. XHTML family document
  types are XML based, and ultimately are designed
  to work in conjunction with XML-based user
  agents. The details of this family and its
  evolution are discussed in more detail in
  XHTMLMOD.
• XHTML 1.0 (this specification) is the first
  document type in the XHTML family. It is a
  reformulation of the three HTML 4 document types
  as applications of XML 1.0 XML. It is intended
  to be used as a language for content that is both
  XML-conforming and, if some simple guidelines are
  followed, operates in HTML 4 conforming user
  agents. Developers who migrate their content to
  XHTML 1.0 will realize the following benefits
• XHTML documents are XML conforming. As such, they
  are readily viewed, edited, and validated with
  standard XML tools.
• XHTML documents can be written to operate as well
  or better than they did before in existing
  HTML 4-conforming user agents as well as in new,
  XHTML 1.0 conforming user agents.
• XHTML documents can utilize applications (e.g.
  scripts and applets) that rely upon either the
  HTML Document Object Model or the XML Document
  Object Model DOM.
• As the XHTML family evolves, documents conforming
  to XHTML 1.0 will be more likely to interoperate
  within and among various XHTML environments.
• The XHTML family is the next step in the
  evolution of the Internet. By migrating to XHTML
  today, content developers can enter the XML world
  with all of its attendant benefits, while still
  remaining confident in their content's backward
  and future compatibility.

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Terrorism
http//www.arabteam2000-forum.com/
Jihad??????????(????)???????
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Watermark embedding
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Watermark detection
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Classification of watermarkingby host

• Image
• Audio
• Video
• Text (Document)
• Software / Executive code
• Database

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Text watermarking Information Hiding
Watermarking
Information hiding
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Any redundance?
NO
Character
Code
One to one
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Utilize format information

• Line-shift Coding
• vertically displacing an entire text line
• Word-shift Coding
• horizontally shifting the location of a word
  within a text line
• Character feature coding
• altering a particular feature of an individual
  character

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Utilize language information

• Synonym substitution
• Syntactic transform
• TMR tree (text meaning representation)
• Add spaces at the end of a line

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Text recoverable watermarking

• Format based watermarking?
• Natural language watermarking?
• How to combine??
• Text recoverable watermarking???