Visual Signature Profile OASIS DSSX

1
Visual Signature Profile OASIS - DSS-X
2
Agenda

• General Requirements Digital Signature
  operation
• Visual Signature content
• Verification Operation

3
General Definition

• The Digital Signature service will support adding
  a visual signature inside a given document as
  part of a digital signature operation.
• The verification service will supply visual
  related information and may include visible
  indication related to the validity of the digital
  signature.

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Document Types

• Q Which documents types to support?
• Today, there are existing standard and
  proprietary implementations of a visible
  signature
• PDF a visual signature is part of the PDF
  standard
• OFFICE 2007 OOXML relatively new
  implementation
• TIFF, Office XP/2003 Proprietary
  implementations
• Open Office Are not familiar with an existing
  implementation
• A The standard will not be limited to a certain
  type of document

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Signature Field

• Q Geometry and Visual Structure of the Visible
  Signature?
• A Signature field is a placeholder for a
  digital signature and a visible signature.
• A Signature field is identified by its xsID
• The signature field is located inside the
  document (page, (x,y) coordinates) and may
  contain meta information such as the intended
  structure of the visible signature.
• A The signature field terminology will be used

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Multiple Signatures per doc

• Q Multiple visible signature inside a document?
• A document can be prepared to have many signature
  field
• A As part of the signature operation, a field
  identification will be given

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Field Management operations

• Q Support of other operations such as signature
  field creation, clear an existing signature ?
• A No, the profile will support only a digital
  signature operation. Other field management
  operations may be handled elsewhere.

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Usage Scenario

• Three types of scenarios where identified
• Simple Workflow ScenarioThe document already
  contain signature fields. The client indicates a
  single field to be signed.
• Document Submission The document does not have
  any signature field embedded. The digital
  signature operation will generate a signature
  field and then sign it.
• Complex Signature RequestMixtures of the above
  scenarios.Q Will this usages scenario lead to
  restrictions/conformance levels? For example, the
  service will not allow creating a signature field
  in the Workflow scenario.

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Vis. Signature displays a dig. Signature

• Q Support cases where the Visible Signature
  encode digital signature information?
• On some documents type (for example, PDF), the
  digital signature is based on the visual
  signature and therefore the digital signature
  cannot be encoded into the visual signature.
• A the profile is flexible so that depending of
  the document type, it will allow displaying
  digital sig. content.

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Visible Signature content

• Signer Information items will be extracted from
  the signers certificate
• CA information items will be extracted from the
  signers certificate
• Signature time
• Signers Related image
• Additional application information Reason for
  the signature operation
• Digital Signature
• Encoded digital signature
• Scanable digital signature

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Visible Signature content

• The information is either passed to the digital
  signature service as part of a document
  submission scenario or encoded inside the
  signature field.
• The configuration includes sub-elements, each
  element (text or image) will be incorporated to
  the signature field in a certain located
  identified by (x,y) coordinates.

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DSSSign operation

• The profile adds the following information that
  should be passed to the digital signature
  service
• Document Type PDF, OOXML, Open Office,
• Field ID
• Visual Signature Position
• Visual Signature configuration

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DSSSign operation document type

• Document Content and type using the
  element in the DSSSign request. will
  include the document content.The MimeType
  attribute will include the type of the document.
• PDF application/pdf ODF
  application/vnd.oasis.opendocument.textDOCX
  application/vnd.openxmlformats-officedocument.wor
  dprocessingml.documentTIF - image/tiff
• If the document is sent via
  the mime type will be taken.
• Mime Type is a mandatory parameter.

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DSSSign operation optional inputs

• useoptional/
• useoptional/
• useoptional/
• useoptional/
• DocumentID will be used if several documents need
  to be signed.
• Should the VisualSignaturePosition defined as
  abstract? If so should the profile include
  position terminology relevant to document types?

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DSSSign operation Position

• typeVisualSignaturePositionType
• 
  
• typexsinteger/
• 
  
• 
  
• useoptional/
• useoptional/

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DSSSign operation Configuration

• typeVisualSignatureDisplayConfigType
• ype
• useoptional
• useoptional/
• useoptional/

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DSSSign operation Configuration

• typeVisualSignatureDisplayConfigType
• ype
• useoptional
• useoptional/
• useoptional/

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DSSSign operation Configuration

• ition/
• nameSimpleVisualSignatureElementPosition
• Should the position be defined as an abstract
  type here as well?

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DSSVerify operation

• Optional Inputs
• Field ID Only the digital signature that is
  linked to the given signature field is verified.
• IncludeVisibleIndication The Verify service
  will embed a visual indication into the visible
  signature that indicates the validation status of
  the digital signature.
• Optional output
• Field ID The ID of the validated field.
• DocumentWithSignature
• In the case of IncludeVisibleIndication, the
  updated document is retrieved.

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Conformance

• Is Conformance necessary?
• Should we take the