April 13, 1995

John Lowry
Senior Member of the Technical Staff

Bolt Beranek and Newman, Inc.
70 Fawcett St
Cambridge, MA.  02138  

email: jlowry@bbn.com

(617) 873-2435 Direct
(617) 873-4086 Fax


Project: Location Independent Information Object Security
(IOS)

Bolt Beranek and Newman, Inc. (BBN), under contract to the
Advanced Research Projects Agency (ARPA), has developed the
Information Object Security (IOS) Tools.  These tools use
object identifiers which are registered as Computer Security
Objects.  ARPA has unlimited rights in the software
containing the objects.  BBN specified, created, and named
the objects under contract to ARPA, and remains the primary
point of contact on all questions regarding naming
conflicts.  The NIST Computer Security Objects Register
(CSOR) assumes no responsibility pertaining to any inquiry
regarding ownership or naming conflicts. 

The IOS software is publicly available and can be obtained
on the Internet for anonymous ftp at ests.bbn.com. 

Object naming information
-------------------------

   IOS Confidentiality Component: 2.16.840.101.3.3.0.2

      iosp (3) components (0) confidentialityComponent (2)

   id-ios-confidentialityComponent


Object definition and description
---------------------------------

The confidentiality component is one of several components
defined by the Location Independent Information Object
Security (IOS) project.  The IOS components are used singly
or in combination with others to achieve a variety of
security services.

This is a syntax that denotes an IOS confidentiality
component. The confidentiality component is used to provide
confidentiality  and confidentiality-based access control
for a list of components.  

This construct supports both symmetric and asymmetric
algorithms and provides data integrity.

   ConfidentialityComponent ::= SEQUENCE {
       dataID              DataID,
       referenceID         ReferenceID,
       certComponentID     [0] DataID OPTIONAL,
       dataConfAlgorithm   AlgorithmIdentifier,
       list                ConfidantList,
       encrypted           ProtectedComponents }

   DataID ::= SEQUENCE {
     componentType   OBJECT IDENTIFIER,
     time            GeneralizedTime,
     random          OCTET STRING SIZE (2..2),
     name            EntityName,

   EntityName ::= SEQUENCE {
     formal          Name OPTIONAL,
     informal        OCTET STRING OPTIONAL}

   ReferenceID ::= SEQUENCE OF DataID

   ConfidantList ::= SEQUENCE OF Confidant

   Confidant ::= SEQUENCE {
        name            EntityName,
        tokenAlgorithm  AlgorithmIdentifier,
        said            OCTET STRING OPTIONAL,
        token           SEQUENCE {
          tokenOID       OBJECT IDENTIFIER,
          tokenData      ENCRYPTED ANY --DEFINED BY
tokenOID--}}

   ProtectedComponents ::= ENCRYPTED ComponentList


Object usage and rules
-----------------------

Confidentiality components contain a DataID with the object
identifier that defines the type of component.  The DataID
provides a unique identification for a component by the
combination of the componentType, time, random, and name
items.  The random element distinguishes among components
created at the  same time by the same user, with the
EntityName.  The informal name field is provided for those
users who do not have Names.

Such users must take care to supply an informal name that
they can be certain is unique, such as an RFC822 address.

The confidentiality component holds information necessary
for named entities to decrypt the referenced component.  The
contents of a token are encrypted and carried as an OCTET
STRING.  

The referenceID lists the component(s) protected by this
component. It is intended purely for convenience in
searching for an encrypted item.

The certComponentID is a pointer to a keyManagementComponent 
containing the certificates and revocation lists associated
with the originator of this component.

The dataConfAlgorithm specifies the algorithm used on the
protected components.

The ConfidantList is an array of entities identified by
name.  It provides a token containing cryptographic
information necessary to reverse and evaluate the
confidentiality service applied to the protected component. 
This list is intended for use with public-key or symmetric
cryptographic systems.  For symmetric systems the security
association identifier is the initialization vector; for
asymmetric systems it is available for any purpose required
by the algorithm.

Tokens containing a hash of the data are used to provide a 
higher level of integrity protection than encryption alone. 
Since some encryption algorithms "recover" at some point
after a bit error, it is possible that the garbled material
would not be apparent as an error in some decrypted objects,
such as a picture.