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Versions: 00 01 02 03 04 05 06 07 08 09 10 RFC 5275

SMIME Working Group                                     S. Turner, IECA
Internet Draft                                         January 28, 2008
Intended Status: Standard Track
Expires: July 28, 2008


               CMS Symmetric Key Management and Distribution
                    draft-ietf-smime-symkeydist-10.txt


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   This Internet-Draft will expire on July 28, 2008.

Copyright Notice

   Copyright (C) The IETF Trust (2008).

Abstract

   This document describes a mechanism to manage (i.e., setup,
   distribute, and rekey) keys used with symmetric cryptographic
   algorithms. Also defined herein is a mechanism to organize users into
   groups to support distribution of encrypted content using symmetric
   cryptographic algorithms. The mechanism uses the Cryptographic
   Message Syntax (CMS) protocol [CMS] and Certificate Management
   Message over CMS (CMC) protocol [CMC] to manage the symmetric keys.
   Any member of the group can then later use this distributed shared
   key to decrypt other CMS encrypted objects with the symmetric key.


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   This mechanism has been developed to support S/MIME Mail List Agents
   (MLAs).

Conventions used in this document

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [RFC2119].

Table of Contents

   1. Introduction...................................................3
      1.1. Applicability to E-mail...................................4
      1.2. Applicability to Repositories.............................5
      1.3. Using the Group Key.......................................5
   2. Architecture...................................................5
   3. Protocol Interactions..........................................7
      3.1. Control Attributes........................................8
         3.1.1. GL USE KEK..........................................10
         3.1.2. Delete GL...........................................13
         3.1.3. Add GL Member.......................................14
         3.1.4. Delete GL Member....................................15
         3.1.5. Rekey GL............................................15
         3.1.6. Add GL Owner........................................16
         3.1.7. Remove GL Owner.....................................17
         3.1.8. GL Key Compromise...................................17
         3.1.9. GL Key Refresh......................................17
         3.1.10. GLA Query Request and Response.....................18
            3.1.10.1. GLA Query Request.............................18
            3.1.10.2. GLA Query Response............................18
            3.1.10.3. Request and Response Types....................19
         3.1.11. Provide Cert.......................................19
         3.1.12. Update Cert........................................20
         3.1.13. GL Key.............................................21
      3.2. Use of CMC, CMS, and PKIX................................23
         3.2.1. Protection Layers...................................23
            3.2.1.1. Minimum Protection.............................23
            3.2.1.2. Additional Protection..........................24
         3.2.2. Combining Requests and Responses....................25
         3.2.3. GLA Generated Messages..............................26
         3.2.4. CMC Control Attributes and CMS Signed Attributes....27
            3.2.4.1. Using cMCStatusInfoExt.........................27
            3.2.4.2. Using transactionId............................30
            3.2.4.3. Using nonces and signingTime...................30
            3.2.4.4. CMC and CMS Attribute Support Requirements.....31
         3.2.5. Resubmitted GL Member Messages......................31
         3.2.6. PKIX Certificate and CRL Profile....................32


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   4. Administrative Messages.......................................32
      4.1. Assign KEK To GL.........................................32
      4.2. Delete GL From GLA.......................................36
      4.3. Add Members To GL........................................38
         4.3.1. GLO Initiated Additions.............................40
         4.3.2. Prospective Member Initiated Additions..............46
      4.4. Delete Members From GL...................................49
         4.4.1. GLO Initiated Deletions.............................50
         4.4.2. Member Initiated Deletions..........................55
      4.5. Request Rekey Of GL......................................57
         4.5.1. GLO Initiated Rekey Requests........................58
         4.5.2. GLA Initiated Rekey Requests........................61
      4.6. Change GLO...............................................62
      4.7. Indicate KEK Compromise..................................64
         4.7.1. GL Member Initiated KEK Compromise Message..........65
         4.7.2. GLO Initiated KEK Compromise Message................66
      4.8. Request KEK Refresh......................................67
      4.9. GLA Query Request and Response...........................69
      4.10. Update Member Certificate...............................71
         4.10.1. GLO and GLA Initiated Update Member Certificate....72
         4.10.2. GL Member Initiated Update Member Certificate......74
   5. Distribution Message..........................................75
      5.1. Distribution Process.....................................76
   6. Algorithms....................................................78
      6.1. KEK Generation Algorithm.................................78
      6.2. Shared KEK Wrap Algorithm................................78
      6.3. Shared KEK Algorithm.....................................78
   7. Message Transport.............................................78
   8. Security Considerations.......................................78
   9. IANA Considerations...........................................80
   10. Acknowledgements.............................................80
   11. References...................................................80
      11.1. Normative References....................................80
      11.2. Informative References..................................81
   12. ASN.1 Module.................................................81

1. Introduction

   With the ever-expanding use of secure electronic communications
   (e.g., S/MIME [MSG]), users require a mechanism to distribute
   encrypted data to multiple recipients (i.e., a group of users). There
   are essentially two ways to encrypt the data for recipients: using
   asymmetric algorithms with public key certificates (PKCs) or
   symmetric algorithms with symmetric keys.

   With asymmetric algorithms, the originator forms an originator-
   determined content-encryption key (CEK) and encrypts the content,


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   using a symmetric algorithm. Then, using an asymmetric algorithm and
   the recipient's PKCs, the originator generates per-recipient
   information that either (a) encrypts the CEK for a particular
   recipient (ktri RecipientInfo CHOICE), or (b) transfers sufficient
   parameters to enable a particular recipient to independently generate
   the same KEK (kari RecipientInfo CHOICE). If the group is large,
   processing of the per-recipient information may take quite some time,
   not to mention the time required to collect and validate the PKCs for
   each of the recipients. Each recipient identifies its per-recipient
   information and uses the private key associated with the public key
   of its PKC to decrypt the CEK and hence gain access to the encrypted
   content.

   With symmetric algorithms, the origination process is slightly
   different. Instead of using PKCs, the originator uses a previously
   distributed secret key-encryption key (KEK) to encrypt the CEK (kekri
   RecipientInfo CHOICE). Only one copy of the encrypted CEK is required
   because all the recipients already have the shared KEK needed to
   decrypt the CEK and hence gain access to the encrypted content.

   The techniques to protect the shared KEK are beyond the scope of this
   document. Only the members of the list and the key manager should
   have the KEK in order to maintain confidentiality. Access control to
   the information protected by the KEK is determined by the entity that
   encrypts the information, as all members of the group have access. If
   the entity that is performing the encryption wants to ensure some
   subset of the group does not gain access to the information either a
   different KEK should be used (shared only with this smaller group) or
   asymmetric algorithms should be used.

1.1. Applicability to E-mail

   One primary audience for this distribution mechanism is e-mail.
   Distribution lists, sometimes referred to as mail lists, support the
   distribution of messages to recipients subscribed to the mail list.
   There are two models for how the mail list can be used. If the
   originator is a member of the mail list, the originator sends
   messages encrypted with the shared KEK to the mail list (e.g.,
   listserv or majordomo) and the message is distributed to the mail
   list members. If the originator is not a member of the mail list
   (does not have the shared KEK), the originator sends the message
   (encrypted for the MLA) to the mail list agent (MLA), and then the
   MLA uses the shared KEK to encrypt the message for the members. In
   either case the recipients of the mail list use the previously
   distributed-shared KEK to decrypt the message.




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1.2. Applicability to Repositories

   Objects can also be distributed via a repository (e.g., Lightweight
   Directory Protocol (LDAP) servers, X.500 Directory System Agents
   (DSAs), Web-based servers). If an object is stored in a repository
   encrypted with a symmetric key algorithm, anyone with the shared KEK
   and access to that object can then decrypt that object. The encrypted
   object and the encrypted, shared KEK can be stored in the repository.

1.3. Using the Group Key

   This document was written with three specific scenarios in mind: two
   supporting mail list agents and one for general message distribution.
   Scenario 1 depicts the originator sending a public key (PK) protected
   message to a MLA who then uses the shared KEK(s) to redistribute the
   message to the members of the list. Scenario 2 depicts the originator
   sending a shared KEK protected message to a MLA who then
   redistributes the message to the members of the list (the MLA only
   adds additional recipients). The key used by the originator could
   either be a key shared amongst all recipients or just between the
   member and the MLA. Note that if the originator use a key shared only
   with the MLA, then the MLA will need to decrypt the message and
   rencrypt the message for the list recipients. Scenario 3 shows an
   originator sending a shared KEK protected message to a group of
   recipients without an intermediate MLA.

                        +---->                   +---->       +---->
         PK   +-----+ S |         S    +-----+ S |         S  |
        ----> | MLA | --+---->   ----> | MLA | --+---->   ----+---->
              +-----+   |              +-----+   |            |
                        +---->                   +---->       +---->
            Scenario 1               Scenario 2           Scenario 3

2. Architecture

   Figure 1 depicts the architecture to support symmetric key
   distribution. The Group List Agent (GLA) supports two distinct
   functions with two different agents:

    - The Key Management Agent (KMA) which is responsible for generating
      the shared KEKs.

    - The Group Management Agent (GMA) which is responsible for managing
      the Group List (GL) to which the shared KEKs are distributed.





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        +----------------------------------------------+
        |              Group List Agent                |    +-------+
        | +------------+    + -----------------------+ |    | Group |
        | |    Key     |    | Group Management Agent | |<-->| List  |
        | | Management |<-->|     +------------+     | |    | Owner |
        | |   Agent    |    |     | Group List |     | |    +-------+
        | +------------+    |     +------------+     | |
        |                   |       /  |  \          | |
        |                   +------------------------+ |
        +----------------------------------------------+
                                 /     |      \
                                /      |       \
                    +----------+ +---------+ +----------+
                    | Member 1 | |   ...   | | Member n |
                    +----------+ +---------+ +----------+

               Figure 1 - Key Distribution Architecture

   A GLA may support multiple KMAs. A GLA in general supports only one
   GMA, but the GMA may support multiple GLs. Multiple KMAs may support
   a GMA in the same fashion as GLAs support multiple KMAs. Assigning a
   particular KMA to a GL is beyond the scope of this document.

   Modeling real world GL implementations shows that there are very
   restrictive GLs, where a human determines GL membership, and very
   open GLs, where there are no restrictions on GL membership. To
   support this spectrum, the mechanism described herein supports both
   managed (i.e., where access control is applied) and unmanaged (i.e.,
   where no access control is applied) GLs. The access control mechanism
   for managed lists is beyond the scope of this document.

   Note: If the distribution for the list is performed by an entity
   other than the originator (e.g., an MLA distributing a mail message),
   this entity can also enforce access control rules.

   In either case, the GL must initially be constructed by an entity
   hereafter called the Group List Owner (GLO). There may be multiple
   entities who 'own' the GL and who are allowed to make changes to the
   GL's properties or membership. The GLO determines if the GL will be
   managed or unmanaged and is the only entity that may delete the GL.
   GLO(s) may or may not be GL members. GLO(s) may also set up lists
   that are closed, where the GLO solely determines GL membership.

   Though Figure 1 depicts the GLA as encompassing both the KMA and GMA
   functions, the two functions could be supported by the same entity or
   they could be supported by two different entities. If two entities
   are used, they could be located on one or two platforms. There is


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   however a close relationship between the KMA and GMA functions. If
   the GMA stores all information pertaining to the GLs and the KMA
   merely generates keys, a corrupted GMA could cause havoc. To protect
   against a corrupted GMA, the KMA would be forced to double check the
   requests it receives to ensure the GMA did not tamper with them.
   These duplicative checks blur the functionality of the two components
   together. For this reason, the interactions between the KMA and GMA
   are beyond the scope of this document.

   Proprietary mechanisms may be used to separate the functions by
   strengthening the trust relationship between the two entities.
   Henceforth, the distinction between the two agents is not discussed
   further; the term GLA will be used to address both functions. It
   should be noted that corrupt GLA can always cause havoc.

3. Protocol Interactions

   There are existing mechanisms (e.g., listserv and majordomo) to
   manage GLs; however, this document does not address securing these
   mechanisms, as they are not standardized. Instead, it defines
   protocol interactions, as depicted in Figure 2, used by the GL
   members, GLA, and GLO(s) to manage GLs and distribute shared KEKs.
   The interactions have been divided into administration messages and
   distribution messages. The administrative messages are the request
   and response messages needed to setup the GL, delete the GL, add
   members to the GL, delete members of the GL, request a group rekey,
   add owners to the GL, remove owners of the GL, indicate a group key
   compromise, refresh a group key, interrogate the GLA, and update
   member's and owner's public key certificates. The distribution
   messages are the messages that distribute the shared KEKs. The
   following sections describe the ASN.1 for both the administration and
   distribution messages. Section 4 describes how to use the
   administration messages, and section 5 describes how to use the
   distribution messages.















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                       +-----+                   +----------+
                       | GLO | <---+      +----> | Member 1 |
                       +-----+     |      |      +----------+
                                   |      |
                    +-----+ <------+      |      +----------+
                    | GLA | <-------------+----> |   ...    |
                    +-----+               |      +----------+
                                          |
                                          |      +----------+
                                          +----> | Member n |
                                                 +----------+

                         Figure 2 - Protocol Interactions

3.1. Control Attributes

   To avoid creating an entirely new protocol, the Certificate
   Management Messages over CMS (CMC) protocol was chosen as the
   foundation of this protocol. The main reason for the choice was the
   layering aspect provided by CMC where one or more control attributes
   are included in message, protected with CMS, to request or respond to
   a desired action. The CMC PKIData structure is used for requests, and
   the CMC PKIResponse structure is used for responses. The content-
   types PKIData and PKIResponse are then encapsulated in CMS's
   SignedData or EnvelopedData, or a combination of the two (see section
   3.2). The following are the control attributes defined in this
   document:

            Control
           Attribute          OID          Syntax
      -------------------  ----------- -----------------
       glUseKEK            id-skd 1    GLUseKEK
       glDelete            id-skd 2    GeneralName
       glAddMember         id-skd 3    GLAddMember
       glDeleteMember      id-skd 4    GLDeleteMember
       glRekey             id-skd 5    GLRekey
       glAddOwner          id-skd 6    GLOwnerAdministration
       glRemoveOwner       id-skd 7    GLOwnerAdministration
       glkCompromise       id-skd 8    GeneralName
       glkRefresh          id-skd 9    GLKRefresh
       glaQueryRequest     id-skd 11   GLAQueryRequest
       glaQueryResponse    id-skd 12   GLAQueryResponse
       glProvideCert       id-skd 13   GLManageCert
       glUpdateCert        id-skd 14   GLManageCert
       glKey               id-skd 15   GLKey




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   In the following conformance tables, the column headings have the
   following meanings: O for originate, R for receive, and F for
   forward. There are three types of implementations: GLOs, GLAs, and GL
   members. The GLO is an optional component hence all GLO O and GLO R
   messages are optional, and GLA F messages are optional. The first
   table includes messages that conformant implementions MUST support.
   The second table includes messages that MAY be implemented. The
   second table should be interpreted as follows: if the control
   attribute is implemented by a component then it must be implemented
   as indicated. For example, if a GLA is implemented that supports the
   glAddMember control attribute, then it MUST support receiving the
   glAddMember message. Note that "-" means not applicable.

                                Required
             Implementation Requirement       |  Control
        GLO   |        GLA        | GL Member | Attribute
       O  R   |  O      R      F  |  O    R   |
      ------- | ----------------- | --------- | ----------
      MAY  -  | MUST    -     MAY |  -   MUST | glProvideCert
      MAY MAY |  -     MUST   MAY | MUST  -   | glUpdateCert
       -   -  | MUST    -      -  |  -   MUST | glKey

                                Optional
              Implementation Requirement      |  Control
        GLO   |        GLA        | GL Member | Attribute
       O   R  |  O      R      F  |  O    R   |
      ------- | ----------------- | --------- | ----------
      MAY  -  |  -     MAY     -  |  -    -   | glUseKEK
      MAY  -  |  -     MAY     -  |  -    -   | glDelete
      MAY MAY |  -     MUST   MAY | MUST  -   | glAddMember
      MAY MAY |  -     MUST   MAY | MUST  -   | glDeleteMember
      MAY  -  |  -     MAY     -  |  -    -   | glRekey
      MAY  -  |  -     MAY     -  |  -    -   | glAddOwner
      MAY  -  |  -     MAY     -  |  -    -   | glRemoveOwner
      MAY MAY |  -     MUST   MAY | MUST  -   | glkCompromise
      MAY  -  |  -     MUST    -  | MUST  -   | glkRefresh
      MAY  -  |  -     SHOULD  -  | MAY   -   | glaQueryRequest
       -  MAY | SHOULD  -      -  |  -   MAY  | glaQueryResponse

   glaQueryResponse and gloResponse are carried in the CMC PKIResponse
   content-type, all other control attributes are carried in the CMC
   PKIData content-type. The exception is glUpdateCert which can be
   carried in either PKIData or PKIResponse.

   Success and failure messages use CMC (see section 3.2.4).




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3.1.1. GL USE KEK

   The GLO uses glUseKEK to request that a shared KEK be assigned to a
   GL. glUseKEK messages MUST be signed by the GLO. The glUseKEK control
   attribute has the syntax GLUseKEK:

     GLUseKEK ::= SEQUENCE {
       glInfo            GLInfo,
       glOwnerInfo       SEQUENCE SIZE (1..MAX) OF GLOwnerInfo,
       glAdministration  GLAdministration DEFAULT 1,
       glKeyAttributes   GLKeyAttributes OPTIONAL }

     GLInfo ::= SEQUENCE {
       glName     GeneralName,
       glAddress  GeneralName }

     GLOwnerInfo ::= SEQUENCE {
       glOwnerName     GeneralName,
       glOwnerAddress  GeneralName,
       certificate     Certificates OPTIONAL }

     Certificates ::= SEQUENCE {
       pKC       [0] Certificate OPTIONAL,
                     -- See [PROFILE]
       aC        [1] SEQUENCE SIZE (1.. MAX) OF
                       AttributeCertificate OPTIONAL,
                     -- See [ACPROF]
       certPath  [2] CertificateSet OPTIONAL }
                     -- From [CMS]

     -- CertificateSet and CertificateChoices are included only
     -- for illustrative purposes as they are imported from [CMS].

     CertificateSet ::= SET SIZE (1..MAX) OF CertificateChoices

     -- CertificateChoices supports X.509 public key certificates in
     -- certificates and v2 attribute certificates in v2AttrCert.

     GLAdministration ::= INTEGER {
       unmanaged  (0),
       managed    (1),
       closed     (2) }







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     GLKeyAttributes ::= SEQUENCE {
       rekeyControlledByGLO        [0] BOOLEAN DEFAULT FALSE,
       recipientsNotMutuallyAware  [1] BOOLEAN DEFAULT TRUE,
       duration                    [2] INTEGER DEFAULT 0,
       generationCounter           [3] INTEGER DEFAULT 2,
       requestedAlgorithm          [4] AlgorithmIdentifier
                                          DEFAULT { id-aes128-wrap } }

   The fields in GLUseKEK have the following meaning:

     - glInfo indicates the name of the GL in glName and the address of
       the GL in glAddress. The glName and glAddress can be the same,
       but this is not always the case. Both the name and address MUST
       be unique for a given GLA.

     - glOwnerInfo indicates:

        -- glOwnerName indicates the name of the owner of the GL. One of
           the names in glOwnerName MUST match one of the names in the
           certificate (either the subject distinguished name or one of
           the subject alternative names) used to sign this
           SignedData.PKIData creating the GL (i.e., the immediate
           signer).

        -- glOwnerAddress indicates the address of the owner of the GL.

        -- certificates MAY be included. It contains the following three
           fields:

            --- certificates.pKC includes the encryption certificate for
                the GLO. It will be used to encrypt responses for the
                GLO.

            --- certificates.aC MAY be included to convey any attribute
                certificate (see [ACPROF]) associated with the
                encryption certificate of the GLO included in
                certificates.pKC.

            --- certificates.certPath MAY also be included to convey
                certificates that might aid the recipient in
                constructing valid certification paths for the
                certificate provided in certificates.pKC and the
                attribute certificates provided in certificates.aC.
                Theses certificates are optional because they might
                already be included elsewhere in the message (e.g., in
                the outer CMS layer).



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        -- glAdministration indicates how the GL ought to be
           administered. The default is for the list to be managed.
           Three values are supported for glAdministration:

            --- Unmanaged - When the GLO sets glAdministration to
                unmanaged, it is allowing prospective members to
                request addition and deletion from the GL without GLO
                intervention.

            --- Managed - When the GLO sets glAdministration to managed,
                it is allowing prospective members to request addition
                and deletion from the GL, but the request is redirected
                by the GLA to GLO for review. The GLO makes the
                determination as to whether to honor the request.

            --- Closed - When the GLO sets glAdministration to closed,
                it is not allowing prospective members to request
                addition or deletion from the GL. The GLA will only
                accept glAddMember and glDeleteMember requests from the
                GLO.

        -- glKeyAttributes indicates the attributes the GLO wants the
           GLA to assign to the shared KEK. If this field is omitted,
           GL rekeys will be controlled by the GLA, the recipients are
           allowed to know about one another, the algorithm will be
           Triple-DES (see paragrpah 7), the shared KEK will be valid
           for a calendar month (i.e., first of the month until the
           last day of the month), and two shared KEKs will be
           distributed initially. The fields in glKeyAttributes have
           the following meaning:

            --- rekeyControlledByGLO indicates whether the GL rekey
                messages will be generated by the GLO or by the GLA.
                The default is for the GLA to control rekeys. If GL
                rekey is controlled by the GLA, the GL will continue to
                be rekeyed until the GLO deletes the GL or changes the
                GL rekey to be GLO controlled.

            --- recipientsNotMutuallyAware indicates that the GLO wants
                the GLA to distribute the shared KEK individually for
                each of the GL members (i.e., a separate glKey message
                is sent to each recipient). The default is for separate
                glKey message not to be required.

                NOTE: This supports lists where one member does not
                know the identities of the other members. For example,
                a list is configured granting submit permissions to


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                only one member. All other members are 'listening.' The
                security policy of the list does not allow the members
                to know who else is on the list. If a glKey is
                constructed for all of the GL members, information
                about each of the members may be derived from the
                information in RecipientInfos. To make sure the glkey
                message does not divulge information about the other
                recipients, a separate glKey message would be sent to
                each GL member.

            --- duration indicates the length of time (in days) during
                which the shared KEK is considered valid. The value
                zero (0) indicates that the shared KEK is valid for a
                calendar month in the UTC Zulu time zone. For example
                if the duration is zero (0), if the GL shared KEK is
                requested on July 24, the first key will be valid until
                the end of July and the next key will be valid for the
                entire month of August. If the value is not zero (0),
                the shared KEK will be valid for the number of days
                indicated by the value. For example, if the value of
                duration is seven (7) and the shared KEK is requested
                on Monday but not generated until Tuesday (2359); the
                shared KEKs will be valid from Tuesday (2359) to
                Tuesday (2359). The exact time of the day is determined
                when the key is generated.

            --- generationCounter indicates the number of keys the GLO
                wants the GLA to distribute. To ensure uninterrupted
                function of the GL two (2) shared KEKs at a minimum
                MUST be initially distributed. The second shared KEK is
                distributed with the first shared KEK, so that when the
                first shared KEK is no longer valid the second key can
                be used. If the GLA controls rekey then it also
                indicates the number of shared KEKs the GLO wants
                outstanding at any one time. See sections 4.5 and 5 for
                more on rekey.

            --- requestedAlgorithm indicates the algorithm and any
                parameters the GLO wants the GLA to use with the shared
                KEK. The parameters are conveyed via the
                SMIMECapabilities attribute (see [MSG]). See section 6
                for more on algorithms.

3.1.2. Delete GL

   GLOs use glDelete to request that a GL be deleted from the GLA. The
   glDelete control attribute has the syntax GeneralName. The glDelete


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   message MUST be signed by the GLO. The name of the GL to be deleted
   is included in GeneralName:

     DeleteGL ::= GeneralName

3.1.3. Add GL Member

   GLOs use the glAddMember to request addition of new members, and
   prospective GL members use the glAddMember to request their own
   addition to the GL. The glAddMember message MUST be signed by either
   the GLO or the prospective GL member. The glAddMember control
   attribute has the syntax GLAddMember:

     GLAddMember ::= SEQUENCE {
      glName    GeneralName,
      glMember  GLMember }

     GLMember ::= SEQUENCE {
       glMemberName     GeneralName,
       glMemberAddress  GeneralName OPTIONAL,
       certificates     Certificates OPTIONAL }

   The fields in GLAddMembers have the following meaning:

     - glName indicates the name of the GL to which the member should be
       added.

     - glMember indicates the particulars for the GL member. Both of the
       following fields must be unique for a given GL:

       -- glMemberName indicates the name of the GL member.

       -- glMemberAddress indicates the GL member's address. It MUST be
          included.

          Note: In some instances the glMemberName and glMemberAddress
          may be the same, but this is not always the case.

       -- certificates MUST be included. It contains the following three
          fields:

          --- certificates.pKC includes the member's encryption
             certificate. It will be used, at least initially, to
             encrypt the shared KEK for that member. If the message is
             generated by a prospective GL member, the pKC MUST be
             included. If the message is generated by a GLO, the pKC
             SHOULD be included.


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          --- certificates.aC MAY be included to convey any attribute
             certificate (see [ACPROF]) associated with the member's
             encryption certificate.

          --- certificates.certPath MAY also be included to convey
             certificates that might aid the recipient in constructing
             valid certification paths for the certificate provided in
             certificates.pKC and the attribute certificates provided
             in certificates.aC. These certificates are optional
             because they might already be included elsewhere in the
             message (e.g., in the outer CMS layer).

3.1.4. Delete GL Member

   GLOs use the glDeleteMember to request deletion of GL members, and GL
   members use the glDeleteMember to request their own removal from the
   GL. The glDeleteMember message MUST be signed by either the GLO or
   the GL member. The glDeleteMember control attribute has the syntax
   GLDeleteMember:

     GLDeleteMember ::= SEQUENCE {
       glName            GeneralName,
       glMemberToDelete  GeneralName }

   The fields in GLDeleteMembers have the following meaning:

     - glName indicates the name of the GL from which the member should
       be removed.

     - glMemberToDelete indicates the name or address of the member to
       be deleted.

3.1.5. Rekey GL

   GLOs use the glRekey to request a GL rekey. The glRekey message MUST
   be signed by the GLO. The glRekey control attribute has the syntax
   GLRekey:

     GLRekey ::= SEQUENCE {
       glName              GeneralName,
       glAdministration    GLAdministration OPTIONAL,
       glNewKeyAttributes  GLNewKeyAttributes OPTIONAL,
       glRekeyAllGLKeys    BOOLEAN OPTIONAL }






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     GLNewKeyAttributes ::= SEQUENCE {
       rekeyControlledByGLO       [0] BOOLEAN OPTIONAL,
       recipientsNotMutuallyAware [1] BOOLEAN OPTIONAL,
       duration                   [2] INTEGER OPTIONAL,
       generationCounter          [3] INTEGER OPTIONAL,
       requestedAlgorithm         [4] AlgorithmIdentifier OPTIONAL }

   The fields in GLRekey have the following meaning:

     - glName indicates the name of the GL to be rekeyed.

     - glAdministration indicates if there is any change to how the GL
       should be administered. See section 3.1.1 for the three options.
       This field is only included if there is a change from the
       previously registered administered.

     - glNewKeyAttributes indicates whether the rekey of the GLO is
       controlled by the GLA or GL, what algorithm and parameters the
       GLO wishes to use, the duration of the key, and how many keys
       will be issued. The field is only included if there is a change
       from the previously registered glKeyAttributes.

     - glRekeyAllGLKeys indicates whether the GLO wants all of the
       outstanding GL's shared KEKs rekeyed. If it is set to TRUE then
       all outstanding KEKs MUST be issued. If it is set to FALSE then
       all outstanding KEKs need not be resissued.

3.1.6. Add GL Owner

   GLOs use the glAddOwner to request that a new GLO be allowed to
   administer the GL. The glAddOwner message MUST be signed by a
   registered GLO. The glAddOwner control attribute has the syntax
   GLOwnerAdministration:

     GLOwnerAdministration ::= SEQUENCE {
       glName       GeneralName,
       glOwnerInfo  GLOwnerInfo }

   The fields in GLAddOwners have the following meaning:

     - glName indicates the name of the GL to which the new GLO should
       be associated.

     - glOwnerInfo indicates the name, address, and certificates of the
       new GLO. As this message includes names of new GLOs, the
       certificates.pKC MUST be included, and it MUST include the
       encryption certificate of the new GLO.


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3.1.7. Remove GL Owner

   GLOs use the glRemoveOwner to request that a GLO be disassociated
   with the GL. The glRemoveOwner message MUST be signed by a registered
   GLO. The glRemoveOwner control attribute has the syntax
   GLOwnerAdministration:

     GLOwnerAdministration ::= SEQUENCE {
       glName       GeneralName,
       glOwnerInfo  GLOwnerInfo }

   The fields in GLRemoveOwners have the following meaning:

     - glName indicates the name of the GL to which the GLO should be
       disassociated.

     - glOwnerInfo indicates the name and address of the GLO to be
       removed. The certificates field SHOULD be omitted, as it will be
       ignored.

3.1.8. GL Key Compromise

   GL members and GLOs use glkCompromise to indicate that the shared KEK
   possessed has been compromised. The glKeyCompromise control attribute
   has the syntax GeneralName. This message is always redirected by the
   GLA to the GLO for further action. The glkCompromise MAY be included
   in an EnvelopedData generated with the compromised shared KEK. The
   name of the GL to which the compromised key is associated with is
   placed in GeneralName:

     GLKCompromise ::= GeneralName

3.1.9. GL Key Refresh

   GL members use the glkRefresh to request that the shared KEK be
   redistributed to them. The glkRefresh control attribute has the
   syntax GLKRefresh.

     GLKRefresh ::= SEQUENCE {
      glName  GeneralName,
      dates   SEQUENCE SIZE (1..MAX) OF Date }

     Date ::= SEQUENCE {
       start GeneralizedTime,
       end   GeneralizedTime OPTIONAL }




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   The fields in GLKRefresh have the following meaning:

     - glName indicates the name of the GL for which the GL member wants
       shared KEKs.

     - dates indicates a date range for keys the GL member wants. The
       start field indicates the first date the GL member wants and the
       end field indicates the last date. The end date MAY be omitted
       to indicate the GL member wants all keys from the specified
       start date to the current date. Note that a procedural mechanism
       is needed to restrict users from accessing messages that they
       are not allowed to access.

3.1.10. GLA Query Request and Response

   There are situations where GLOs and GL members may need to determine
   some information from the GLA about the GL. GLOs and GL members use
   the glaQueryRequest, defined in section 3.1.10.1, to request
   information and GLAs use the glaQueryResponse, defined in section
   3.1.10.2, to return the requested information. Section 3.1.10.3
   includes one request and response type and value; others may be
   defined in additional documents.

3.1.10.1. GLA Query Request

   GLOs and GL members use the glaQueryRequest to ascertain information
   about the GLA. The glaQueryRequest control attribute has the syntax
   GLAQueryRequest:

     GLAQueryRequest ::= SEQUENCE {
       glaRequestType   OBJECT IDENTIFIER,
       glaRequestValue  ANY DEFINED BY glaRequestType }

3.1.10.2. GLA Query Response

   GLAs return the glaQueryResponse after receiving a GLAQueryRequest.
   The glaQueryResponse MUST be signed by a GLA. The glaQueryResponse
   control attribute has the syntax GLAQueryResponse:

     GLAQueryResponse ::= SEQUENCE {
       glaResponseType   OBJECT IDENTIFIER,
       glaResponseValue  ANY DEFINED BY glaResponseType }







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3.1.10.3. Request and Response Types

   Request and Responses are registered as a pair under the following
   object identifier arc:

     id-cmc-glaRR OBJECT IDENTIFIER ::= { id-cmc 99 }

   This document defines one request/response pair for GL members and
   GLOs to query the GLA for the list of algorithm it supports.  The
   following object identifier (OID) is included in the glaQueryType
   field:

     id-cmc-gla-skdAlgRequest OBJECT IDENTIFIER ::={ id-cmc-glaRR 1 }

     SKDAlgRequest ::= NULL

   If the GLA supports GLAQueryRequest and GLAQueryResponse messages,
   the GLA may return the following OID in the glaQueryType field:

     id-cmc-gla-skdAlgResponse OBJECT IDENTIFIER ::= { id-cmc-glaRR 2 }

   The glaQueryValue has the form of the smimeCapabilities attributes as
   defined in [MSG].

3.1.11. Provide Cert

   GLAs and GLOs use the glProvideCert to request that a GL member
   provide an updated or new encryption certificate. The glProvideCert
   message MUST be signed by either GLA or GLO. If the GL member's PKC
   has been revoked, the GLO or GLA MUST NOT use it to generate the
   EnvelopedData that encapsulates the glProvideCert request. The
   glProvideCert control attribute has the syntax GLManageCert:

     GLManageCert ::= SEQUENCE {
       glName    GeneralName,
       glMember  GLMember }

   The fields in GLManageCert have the following meaning:

     - glName indicates the name of the GL to which the GL member's new
       certificate is to be associated.

     - glMember indicates particulars for the GL member:

       -- glMemberName indicates the GL member's name.




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       -- glMemberAddress indicates the GL member's address. It MAY be
          omitted.

       -- certificates SHOULD be omitted.

3.1.12. Update Cert

   GL members and GLOs use the glUpdateCert to provide a new certificate
   for the GL. GL members can generate an unsolicited glUpdateCert or
   generate a response glUpdateCert as a result of receiveing a
   glProvideCert message. GL members MUST sign the glUpdateCert. If the
   GL member's encryption certificate has been revoked, the GL member
   MUST NOT use it to generate the EnvelopedData that encapsulates the
   glUpdateCert request or response. The glUpdateCert control attribute
   has the syntax GLManageCert:

     GLManageCert ::= SEQUENCE {
       glName    GeneralName,
       glMember  GLMember }

   The fields in GLManageCert have the following meaning:

     - glName indicates the name of the GL to which the GL member's new
   certificate should be associated.

     - glMember indicates the particulars for the GL member:

       -- glMemberName indicates the GL member's name.

       -- glMemberAddress indicates the GL member's address. It MAY be
          omitted.

       -- certificates MAY be omitted if the GLManageCert message is
          sent to request the GL member's certificate; otherwise, it
          MUST be included. It includes the following three fields:

            ---- certificates.pKC includes the member's encryption
                certificate that will be used to encrypt the shared KEK
                for that member.

            --- certificates.aC MAY be included to convey one or more
                attribute certificate associated with the member's
                encryption certificate.

            --- certificates.certPath MAY also be included to convey
                certificates that might aid the recipient in
                constructing valid certification paths for the


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                certificate provided in certificates.pKC and the
                attribute certificates provided in certificates.aC.
                These certificates is optional because they might
                already be included elsewhere in the message (e.g., in
                the outer CMS layer).

3.1.13. GL Key

   The GLA uses the glKey to distribute the shared KEK. The glKey
   message MUST be signed by the GLA. The glKey control attribute has
   the syntax GLKey:

     GLKey ::= SEQUENCE {
       glName        GeneralName,
       glIdentifier  KEKIdentifier,      -- See [CMS]
       glkWrapped    RecipientInfos,     -- See [CMS]
       glkAlgorithm  AlgorithmIdentifier,
       glkNotBefore  GeneralizedTime,
       glkNotAfter   GeneralizedTime }

   -- KEKIdentifier is included only for illustrative purposes as
   -- it is imported from [CMS].

     KEKIdentifier ::= SEQUENCE {
       keyIdentifier OCTET STRING,
       date GeneralizedTime OPTIONAL,
       other OtherKeyAttribute OPTIONAL }

   The fields in GLKey have the following meaning:

     - glName is the name of the GL.

     - glIdentifier is the key identifier of the shared KEK. See
       paragraph 6.2.3 of [CMS] for a description of the subfields.

     - glkWrapped is the wrapped shared KEK for the GL for a particular
       duration. The RecipientInfos MUST be generated as specified in
       section 6.2 of [CMS]. The ktri RecipientInfo choice MUST be
       supported. The key in the EncryptedKey field (i.e., the
       distributed shared KEK) MUST be generated according to the
       section concerning random number generation in the security
       considerations of [CMS].

     - glkAlgorithm identifies the algorithm the shared KEK is used
       with. Since no encrypted data content is being conveyed at this
       point, the parameters encoded with the algorithm should be the



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       structure defined for smimeCapabilities rather than encrypted
       content.

     - glkNotBefore indicates the date at which the shared KEK is
       considered valid. GeneralizedTime values MUST be expressed in
       UTC (Zulu) and MUST include seconds (i.e., times are
       YYYYMMDDHHMMSSZ), even where the number of seconds is zero.
       GeneralizedTime values MUST NOT include fractional seconds.

     - glkNotAfter indicates the date after which the shared KEK is
       considered invalid. GeneralizedTime values MUST be expressed in
       UTC (Zulu) and MUST include seconds (i.e., times are
       YYYYMMDDHHMMSSZ), even where the number of seconds is zero.
       GeneralizedTime values MUST NOT include fractional seconds.

   If the glKey message is in response to a glUseKEK message:

     - The GLA MUST generate separate glKey messages for each recipient
       if glUseKEK.glKeyAttributes.recipientsNotMutuallyAware is set to
       TRUE. For each recipient, you want to generate a message that
       contains that recipient's key (i.e., one message with one
       attribute).

     - The GLA MUST generate the requested number of glKey messages. The
       value in glUseKEK.glKeyAttributes.generationCounter indicates
       the number of glKey messages requested.

   If the glKey message is in response to a glRekey message:

     - The GLA MUST generate separate glKey messages for each recipient
       if glRekey.glNewKeyAttributes.recipientsNotMutuallyAware is set
       to TRUE.

     - The GLA MUST generate the requested number of glKey messages. The
       value in glUseKEK.glKeyAttributes.generationCounter indicates
       the number of glKey messages requested.

     - The GLA MUST generate one glKey messagefor each outstanding
       shared KEKs for the GL when glRekeyAllGLKeys is set to TRUE.

   If the glKey message was not in response to a glRekey or glUseKEK
   (e.g., where the GLA controls rekey):

     - The GLA MUST generate separate glKey messages for each recipient
       when glUseKEK.glNewKeyAttributes.recipientsNotMutuallyAware that
       set up the GL was set to TRUE.



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     - The GLA MAY generate glKey messages prior to the duration on the
       last outstanding shared KEK expiring, where the number of glKey
       messages generated is generationCounter minus one (1). Other
       distribution mechanisms can also be supported to support this
       functionality.

3.2. Use of CMC, CMS, and PKIX

   The following sections outline the use of CMC, CMS, and the PKIX
   certificate and CRL profile.

3.2.1. Protection Layers

   The following sections outline the protection required for the
   control attributes defined in this document.

   Note: There are multiple ways to encapsulate SignedData and
   EnvelopedData. The first is to use a MIME wrapper around each
   ContentInfo, as specified in [MSG]. The second is to not use a MIME
   wrapper around each ContentInfo, as specified in Transporting S/MIME
   Objects in X.400 [X400TRANS].

3.2.1.1. Minimum Protection

   At a minimum, a SignedData MUST protect each request and response
   encapsulated in PKIData and PKIResponse. The following is a depiction
   of the minimum wrappings:

        Minimum Protection
        ------------------
        SignedData
         PKIData or PKIResponse
          controlSequence

   Prior to taking any action on any request or response SignedData(s)
   MUST be processed according to [CMS].













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3.2.1.2. Additional Protection

   An additional EnvelopedData MAY also be used to provide
   confidentiality of the request and response. An additional SignedData
   MAY also be added to provide authentication and integrity of the
   encapsulated EnvelopedData. The following is a depiction of the
   optional additional wrappings:

                                       Authentication and Integrity
        Confidentiality Protection     of Confidentiality Protection
        --------------------------     -----------------------------
        EnvelopedData                  SignedData
         SignedData                     EnvelopedData
          PKIData or PKIResponse         SignedData
           controlSequence                PKIData or PKIResponse
                                           controlSequence

   If an incoming message is encrypted, the confidentiality of the
   message MUST be preserved. All EnvelopedData objects MUST be
   processed as specified in [CMS]. If a SignedData is added over an
   EnvelopedData, a ContentHints attribute SHOULD be added. See
   paragraph 2.9 of Extended Security Services for S/MIME [ESS].

   If the GLO or GL member applies confidentiality to a request, the
   EnvelopedData MUST include the GLA as a recipient. If the GLA
   forwards the GL member request to the GLO, then the GLA MUST decrypt
   the EnvelopedData content, strip the confidentiality layer, and apply
   its own confidentiality layer as an EnvelopedData with the GLO as a
   recipient.




















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3.2.2. Combining Requests and Responses

   Multiple requests and response corresponding to a GL MAY be included
   in one PKIData.controlSequence or PKIResponse.controlSequence.
   Requests and responses for multiple GLs MAY be combined in one
   PKIData or PKIResponse by using PKIData.cmsSequence and
   PKIResponse.cmsSequence. A separate cmsSequence MUST be used for
   different GLs. That is, requests corresponding to two different GLs
   are included in different cmsSequences. The following is a diagram
   depicting multiple requests and responses combined in one PKIData and
   PKIResponse:

            Multiple Request and Response
        Request                        Response
        -------                        --------
        SignedData                      SignedData
         PKIData                         PKIResponse
          cmsSequence                     cmsSequence
           SignedData                      SignedData
            PKIData                         PKIResponse
             controlSequence                 controlSequence
              One or more requests          One or more responses
              corresponding to one GL         corresponding to one GL
           SignedData                      SignedData
            PKIData                         PKIResponse
             controlSequence                 controlSequence
              One or more requests          One or more responses
              corresponding to another GL    corresponding to another GL

   When applying confidentiality to multiple requests and responses, all
   of the requests/response MAY be included in one EnvelopedData.


















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   The following is a depiction:

        Confidentiality of Multiple Requests and Responses
        Wrapped Together
        ----------------
        EnvelopedData
         SignedData
          PKIData
           cmsSequence
            SignedData
             PKIResponse
              controlSequence
               One or more requests
               corresponding to one GL
            SignedData
             PKIData
              controlSequence
               One or more requests
               corresponding to one GL

   Certain combinations of requests in one PKIData.controlSequence and
   one PKIResponse.controlSequence are not allowed. The invalid
   combinations listed here MUST NOT be generated:

           Invalid Combinations
        ---------------------------
        glUseKEK   & glDeleteMember
        glUseKEK   & glRekey
        glUseKEK   & glDelete
        glDelete   & glAddMember
        glDelete   & glDeleteMember
        glDelete   & glRekey
        glDelete   & glAddOwner
        glDelete   & glRemoveOwner

   To avoid unnecessary errors, certain requests and responses SHOULD be
   processed prior to others. The following is the priority of message
   processing, if not listed it is an implementation decision as to
   which to process first: glUseKEK before glAddMember, glRekey before
   glAddMember, and glDeleteMember before glRekey. Note that there is a
   processing priority but it does not imply an ordering within the
   content.

3.2.3. GLA Generated Messages

   When the GLA generates a success or fail message, it generates one
   for each request. SKDFailInfo values of unsupportedDuration,


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   unsupportedDeliveryMethod, unsupportedAlgorithm, noGLONameMatch,
   nameAlreadyInUse, alreadyAnOwner, notAnOwner are not returned to GL
   members.

   If GLKeyAttributes.recipientsNotMutuallyAware is set to TRUE, a
   separate PKIResponse.cMCStatusInfoExt and PKIData.glKey MUST be
   generated for each recipient. However, it is valid to send one
   message with multiple attributes to the same recipient.

   If the GL has multiple GLOs, the GLA MUST send cMCStatusInfoExt
   messages to the requesting GLO. The mechanism to determine which GLO
   made the request is beyond the scope of this document.

   If a GL is managed and the GLA receives a glAddMember,
   glDeleteMember, or glkCompromise message, the GLA redirects the
   request to the GLO for review. An additional, SignedData MUST be
   applied to the redirected request as follows:

        GLA Forwarded Requests
        ----------------------
        SignedData
         PKIData
           cmsSequence
             SignedData
              PKIData
               controlSequence

3.2.4. CMC Control Attributes and CMS Signed Attributes

   CMC carries control attributes as CMS signed attributes. These
   attributes are defined in [CMC] and [CMS]. Some of these attributes
   are REQUIRED; others are OPTIONAL. The required attributes are as
   follows: cMCStatusInfoExt transactionId, senderNonce, recipientNonce,
   queryPending, and signingTime. Other attributes can also be used;
   however, their use is beyond the scope of this document. The
   following sections specify requirements in addition to those already
   specified in [CMC] and [CMS].

3.2.4.1. Using cMCStatusInfoExt

   cMCStatusInfoExt is used by GLAs to indicate to GLOs and GL members
   that a request was unsuccessful. Two classes of failure codes are
   used within this document. Errors from the CMCFailInfo list, found in
   section 5.1.4 of CMC, are encoded as defined in CMC. Error codes
   defined in this document are encoded using the ExtendedFailInfo field
   of the cmcStatusInfoExt structure. If the same failure code applies
   to multiple commands, a single cmcStatusInfoExt structure can be used


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   with multiple items in cMCStatusInfoExt.bodyList. The GLA MAY also
   return other pertinent information in statusString. The SKDFailInfo
   object identifier and value are:

     id-cet-skdFailInfo OBJECT IDENTIFIER ::= { iso(1)
       identified-organization(3) dod(6) internet(1) security(5)
       mechanisms(5) pkix(7) cet(15) skdFailInfo(1) }

     SKDFailInfo ::= INTEGER {
       unspecified           (0),
       closedGL              (1),
       unsupportedDuration   (2),
       noGLACertificate      (3),
       invalidCert           (4),
       unsupportedAlgorithm  (5),
       noGLONameMatch        (6),
       invalidGLName         (7),
       nameAlreadyInUse      (8),
       noSpam                (9),
       deniedAccess          (10),
       alreadyAMember        (11),
       notAMember            (12),
       alreadyAnOwner        (13),
       notAnOwner            (14) }

   The values have the following meaning:

     - unspecified indicates that the GLA is unable or unwilling to
       perform the requested action and does not want to indicate the
       reason.

     - closedGL indicates that members can only be added or deleted by
       the GLO.

     - unsupportedDuration indicates the GLA does not support generating
       keys that are valid for the requested duration.

     - noGLACertificate indicates that the GLA does not have a valid
       certificate.

     - invalidCert indicates the member's encryption certificate was not
       verifiable (i.e., signature did not validate, certificate's
       serial number present on a CRL, expired, etc.).

     - unsupportedAlgorithm indicates the GLA does not support the
       requested algorithm.



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     - noGLONameMatch indicates that one of the names in the certificate
       used to sign a request does not match the name of a registered
       GLO.

     - invalidGLName indicates the GLA does not support the glName
       present in the request.

     - nameAlreadyInUse indicates the glName is already assigned on the
       GLA.

     - noSpam indicates the prospective GL member did not sign the
       request (i.e., if the name in glMember.glMemberName does not
       match one of the names (either the subject distinguished name or
       one of the subject alternative names) in the certificate used to
       sign the request).

     - alreadyAMember indicates the prospective GL member is already a
       GL member.

     - notAMember indicates the prospective GL member to be deleted is
       not presently a GL member.

     - alreadyAnOwner indicates the prospective GLO is already a GLO.

     - notAnOwner indicates the prospective GLO to be deleted is not
       presently a GLO.

   cMCStatusInfoExt is used by GLAs to indicate to GLOs and GL members
   that a request was successfully completed. If the request was
   successful, the GLA returns a cMCStatusInfoExt response with
   cMCStatus.success and optionally other pertinent information in
   statusString.

   When the GL is managed and the GLO has reviewed GL member initiated
   glAddMember, glDeleteMember, and glkComrpomise requests, the GLO uses
   cMCStatusInfoExt to indicate the success or failure of the request.
   If the request is allowed, cMCStatus.success is returned  and
   statusString is optionally returned to convey additional information.
   If the request is denied, cMCStatus.failed is returned and
   statusString is optionally returned to convey additional information.
   Additionally, the appropriate SKDFailInfo can be included in
   cMCStatusInfoExt.extendedFailInfo.

   cMCStatusInfoExt is used by GLOs, GLAs, and GL members to indicate
   that signature verification failed. If the signature failed to verify
   over any control attibute except a cMCStatusInfoExt, a
   cMCStatusInfoExt control attribute MUST be returned indicating


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   cMCStatus.failed and otherInfo.failInfo.badMessageCheck. If the
   signature over the outermost PKIData failed, the bodyList value is
   zero (0). If the signature over any other PKIData failed the bodyList
   value is the bodyPartId value from the request or response. GLOs and
   GL members who receive cMCStatusInfoExt messages whose signatures are
   invalid SHOULD generate a new request to avoid badMessageCheck
   message loops.

   cMCStatusInfoExt is also used by GLOs and GLAs to indicate that a
   request could not be performed immediately. If the request could not
   be processed immediately by the GLA or GLO, the cMCStatusInfoExt
   control attribute MUST be returned indicating cMCStatus.pending and
   otherInfo.pendInfo. When requests are redirected to the GLO for
   approval (for managed lists), the GLA MUST NOT return a
   cMCStatusInfoExt indicating query pending.

   cMCStatusInfoExt is also used by GLAs to indicate that a
   glaQueryRequest is not supported. If the glaQueryRequest is not
   supported, the cMCStatusInfoExt control attribute MUST be returned
   indicating cMCStatus.noSupport and statusString is optionally
   returned to convey additional information.

   cMCStatusInfoExt is also used by GL members, GLOs, and GLAs to
   indicate that the signingTime (see section 3.2.4.3) is not close
   enough to the locally specified time. If the local time is not close
   enough to the time specified in signingTime, a cMCStatus.failed and
   otherInfo.failInfo.badTime MAY be returned.

3.2.4.2. Using transactionId

   transactionId MAY be included by GLOs, GLAs, or GL members to
   identify a given transaction. All subsequent requests and responses
   related to the original request MUST include the same transactionId
   control attribute. If GL members include a transactionId and the
   request is redirected to the GLO, the GLA MAY include an additional
   transactionId in the outer PKIData. If the GLA included an additional
   transactionId in the outer PKIData, when the GLO generates a
   cMCStatusInfoExt response it generates one for the GLA with the GLA's
   transactionId and one for the GL member with the GL member's
   transactionId.

3.2.4.3. Using nonces and signingTime

   The use of nonces (see section 5.6 of [CMC]) and an indication of
   when the message was signed (see section 11.3 of [CMS]) can be used
   to provide application-level replay prevention.



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   To protect the GL, all messages MUST include the signingTime
   attribute. Message originators and recipients can then use the time
   provided in this attribute to determine whether they have previously
   received the message.

   If the originating message includes a senderNonce, the response to
   the message MUST include the received senderNonce value as the
   recipientNonce and a new value as the senderNonce value in the
   response.

   If a GLA aggragates multiple messages together or forwards a message
   to a GLO, the GLA MAY optionally generate a new nonce value and
   include that in the wrapping message. When the response comes back
   from the GLO, the GLA builds a response to the originator(s) of the
   message(s) and deals with each of the nonce values from the
   originating messages.

   For these attributes it is necessary to maintain state information on
   exchanges to compare one result to another. The time period for which
   this information is maintained in a local policy.

3.2.4.4. CMC and CMS Attribute Support Requirements

   The following are the implementation requirements for CMC control
   attributes  and CMS signed attributes for an implementation be
   considered conformant to this specification:

             Implementation Requirement     |
         GLO    |      GLA      | GL Member | Attribute
       O    R   |  O    R    F  |  O    R   |
      --------- | ------------- | --------- | ----------
      MUST MUST | MUST MUST  -  | MUST MUST | cMCStatusInfoExt
      MAY  MAY  | MUST MUST  -  | MAY  MAY  | transactionId
      MAY  MAY  | MUST MUST  -  | MAY  MAY  | senderNonce
      MAY  MAY  | MUST MUST  -  | MAY  MAY  | recepientNonce
      MUST MUST | MUST MUST  -  | MUST MUST | SKDFailInfo
      MUST MUST | MUST MUST  -  | MUST MUST | signingTime

3.2.5. Resubmitted GL Member Messages

   When the GL is managed, the GLA forwards the GL member requests to
   the GLO for GLO approval by creating a new request message containing
   the GL member request(s) as a cmsSequence item.  If the GLO approves
   the request it can either add a new layer of wrapping and send it
   back to the GLA or create a new message and send it to the GLA. (Note
   in this case there are now 3 layers of PKIData messages with
   appropriate signing layers.)


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3.2.6. PKIX Certificate and CRL Profile

   Signatures, certificates, and CRLs are verified according to the PKIX
   profile [PROFILE].

   Name matching is performed according to the PKIX profile [PROFILE].

   All distinguished name forms must follow the UTF8String convention
   noted in the PKIX profile [PROFILE].

   A certificate per-GL would be issued to the GLA.

   GL policy may mandate that the GL member's address be included in the
   GL member's certificate.

4. Administrative Messages

   There are a number of administrative messages that must be performed
   to manage a GL. The following sections describe each request and
   response message combination in detail. The procedures defined in
   this section are not prescriptive.

4.1. Assign KEK To GL

   Prior to generating a group key, a GL needs to be setup and a shared
   KEK assigned to the GL. Figure 3 depicts the protocol interactions to
   setup and assign a shared KEK. Note that error messages are not
   depicted in Figure 3. Additionally, behavior for the optional
   transactionId, senderNonce, and recipientNonce CMC control attributes
   is not addressed in these procedures.

                    +-----+   1    2  +-----+
                    | GLA | <-------> | GLO |
                    +-----+           +-----+

                   Figure 3 - Create Group List

   The process is as follows:

     1 - The GLO is the entity responsible for requesting the creation
        of the GL. The GLO sends a
        SignedData.PKIData.controlSequence.glUseKEK request to the GLA
        (1 in Figure 3). The GLO MUST include: glName, glAddress,
        glOwnerName, glOwnerAddress, and glAdministration. The GLO MAY
        also include their preferences for the shared KEK in
        glKeyAttributes by indicating whether the GLO controls the
        rekey in rekeyControlledByGLO, whether separate glKey messages


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        should be sent to each recipient in recipientsNotMutuallyAware,
        the requested algorithm to be used with the shared KEK in
        requestedAlgorithm, the duration of the shared KEK, and how
        many shared KEKs should be initially distributed in
        generationCounter. The GLO MUST also include the signingTime
        attribute with this request.

     1.a - If the GLO knows of members to be added to the GL, the
           glAddMember request(s) MAY be included in the same
           controlSequence as the glUseKEK request (see section 3.2.2).
           The GLO indicates the same glName in the glAddMember request
           as in glUseKEK.glInfo.glName. Further glAddMember procedures
           are covered in section 4.3.

     1.b - The GLO can apply confidentiality to the request by
           encapsulating the SignedData.PKIData in an EnvelopedData
           (see section 3.2.1.2).

     1.c - The GLO can also optionally apply another SignedData over the
           EnvelopedData (see section 3.2.1.2).

     2 - Upon receipt of the request, the GLA checks the signingTime and
        verifies the signature on the inner most SignedData.PKIData. If
        an additional SignedData and/or EnvelopedData encapsulates the
        request (see sections 3.2.1.2 and 3.2.2), the GLA verifies the
        outer signature(s) and/or decrypt the outer layer(s) prior to
        verifying the signature on the inner most SignedData.

     2.a - If the signingTime attribute value is not within the locally
           accepted time window, the GLA MAY return a response
           indicating cMCStatus.failed and otherInfo.failInfo.badTime
           and a signingTime attribute.

     2.b - Else if signature processing continues and if the signatures
           do not verify, the GLA returns a cMCStatusInfoExt response
           indicating cMCStatus.failed and
           otherInfo.failInfo.badMessageCheck. Additionally, a
           signingTime attribute is included with the response.

     2.c - Else if the signatures do verify but the GLA does not have a
           valid certificate, the GLA returns a cMCStatusInfoExt with
           cMCStatus.failed and otherInfo.extendedFailInfo.SKDFailInfo
           value of noValidGLACertificate. Additionally, a signingTime
           attribute is included with the response. Instead of
           immediately returning the error code, the GLA attempts to
           get a certificate, possibly using [CMC].



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     2.d - Else the signatures are valid and the GLA does have a valid
           certificate, the GLA checks that one of the names in the
           certificate used to sign the request matches one of the
           names in glUseKEK.glOwnerInfo.glOwnerName.

     2.d.1 - If the names do not match, the GLA returns a response
             indicating cMCStatusInfoExt with cMCStatus.failed and
             otherInfo.extendedFailInfo.SKDFailInfo value of
             noGLONameMatch. Additionally, a signingTime attribute is
             included with the response.

     2.d.2 - Else if the names all match, the GLA checks that the glName
             and glAddress is not already in use. The GLA also checks
             any glAddMember included within the controlSequence with
             this glUseKEK. Further processing of the glAddMember is
             covered in section 4.3.

     2.d.2.a - If the glName is already in use the GLA returns a
               response indicating cMCStatusInfoExt with
               cMCStatus.failed and
               otherInfo.extendedFailInfo.SKDFailInfo value of
               nameAlreadyInUse. Additionally, a signingTime attribute
               is included with the response.

     2.d.2.b - Else if the requestedAlgorithm is not supported, the GLA
               returns a response indicating cMCStatusInfoExt with
               cMCStatus.failed and
               otherInfo.extendedFailInfo.SKDFailInfo value of
               unsupportedAlgorithm. Additionally, a signingTime
               attribute is included with the response.

     2.d.2.c - Else if the duration cannot be supported, determining
               this is beyond the scope of this document, the GLA
               returns a response indicating cMCStatusInfoExt with
               cMCStatus.failed and
               otherInfo.extendedFailInfo.SKDFailInfo value of
               unsupportedDuration. Additionally, a signingTime
               attribute is included with the response.

     2.d.2.d - Else if the GL cannot be supported for other reasons,
               which the GLA does not wish to disclose, the GLA returns
               a response indicating cMCStatusInfoExt with
               cMCStatus.failed and
               otherInfo.extendedFailInfo.SKDFailInfo value of
               unspecified. Additionally, a signingTime attribute is
               included with the response.



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     2.d.2.e - Else if the glName is not already in use, the duration
               can be supported, and the requestedAlgorithm is
               supported, the GLA MUST return a cMCStatusInfoExt
               indicating cMCStatus.success and a signingTime attribute.
               (2 in Figure 3). The GLA also takes administrative
               actions, which are beyond the scope of this document, to
               store the glName, glAddress, glKeyAttributes,
               glOwnerName, and glOwnerAddress. The GLA also sends a
               glKey message as described in section 5.

     2.d.2.e.1 - The GLA can apply confidentiality to the response by
                 encapsulating the SignedData.PKIResponse in an
                 EnvelopedData if the request was encapsulated in an
                 EnvelopedData (see section 3.2.1.2).

     2.d.2.e.2 - The GLA can also optionally apply another SignedData
                 over the EnvelopedData (see section 3.2.1.2).

     3 - Upon receipt of the cMCStatusInfoExt responses, the GLO checks
        the signingTime and verifies the GLA signature(s). If an
        additional SignedData and/or EnvelopedData encapsulates the
        response (see section 3.2.1.2 or 3.2.2), the GLO verifies the
        outer signature and/or decrypt the outer layer prior to
        verifying the signature on the inner most SignedData.

     3.a - If the signingTime attribute value is not within the locally
           accepted time window, the GLO MAY return a response
           indicating cMCStatus.failed and otherInfo.failInfo.badTime
           and a signingTime attribute.

     3.b - Else if signature processing continues and if the signatures
           do verify, the GLO MUST check that one of the names in the
           certificate used to sign the response matches the name of
           the GL.

     3.b.1 - If the name of the GL does not match the name present in
             the certificate used to sign the message, the GLO should
             not believe the response.

     3.b.2 - Else if the name of the GL does match the name present in
             the certificate and:

     3.b.2.a - If the signatures do verify and the response was
               cMCStatusInfoExt indicating cMCStatus.success, the GLO
               has successfully created the GL.




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     3.b.2.b - Else if the signatures are valid and the response is
               cMCStatusInfoExt.cMCStatus.failed with any reason, the
               GLO can reattempt to create the GL using the information
               provided in the response. The GLO can also use the
               glaQueryRequest to determine the algorithms and other
               characteristics supported by the GLA (see section 4.9).

4.2. Delete GL From GLA

   From time to time, there are instances when a GL is no longer needed.
   In this case, the GLO deletes the GL. Figure 4 depicts that protocol
   interactions to delete a GL. Note that behavior for the optional
   transactionId, senderNonce, and recipientNonce CMC control attributes
   is not addressed in these procedures.

                     +-----+   1    2  +-----+
                     | GLA | <-------> | GLO |
                     +-----+           +-----+

                    Figure 4 - Delete Group List

   The process is as follows:

     1 - The GLO is responsible for requesting the deletion of the GL.
        The GLO sends a SignedData.PKIData.controlSequence.glDelete
        request to the GLA (1 in Figure 4). The name of the GL to be
        deleted is included in GeneralName. The GLO MUST also include
        the signingTime attribute and can also include a transactionId
        and senderNonce attributes.

     1.a - The GLO can optionally apply confidentiality to the request
           by encapsulating the SignedData.PKIData in an EnvelopedData
           (see section 3.2.1.2).

     1.b - The GLO MAY optionally apply another SignedData over the
           EnvelopedData (see section 3.2.1.2).

     2 - Upon receipt of the request the GLA checks the signingTime and
        verifies the signature on the inner most SignedData.PKIData. If
        an additional SignedData and/or EnvelopedData encapsulates the
        request (see section 3.2.1.2 or 3.2.2), the GLA verifies the
        outer signature and/or decrypt the outer layer prior to
        verifying the signature on the inner most SignedData.

     2.a - If the signingTime attribute value is not within the locally
           accepted time window, the GLA MAY return a response



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           indicating cMCStatus.failed and otherInfo.failInfo.badTime
           and a signingTime attribute.

     2.b - Else if signature processing continues and if the signatures
           cannot be verified, the GLA returns a cMCStatusInfoExt
           response indicating cMCStatus.failed and
           otherInfo.failInfo.badMessageCheck. Additionally, a
           signingTime attribute is included with the response.

     2.c - Else if the signatures verify, the GLA makes sure the GL is
           supported by checking the name of the GL matches a glName
           stored on the GLA.

     2.c.1 - If the glName is not supported by the GLA, the GLA returns
            a response indicating cMCStatusInfoExt with
            cMCStatus.failed and otherInfo.extendedFailInfo.SKDFailInfo
            value of invalidGLName. Additionally, a signingTime
            attribute is included with the response.

     2.c.2 - Else if the glName is supported by the GLA, the GLA ensures
            a registered GLO signed the glDelete request by checking if
            one of the names present in the digital signature
            certificate used to sign the glDelete request matches a
            registered GLO.

     2.c.2.a - If the names do not match, the GLA returns a response
               indicating cMCStatusInfoExt with cMCStatus.failed and
               otherInfo.extendedFailInfo.SKDFailInfo value of
               noGLONameMatch. Additionally, a signingTime attribute is
               included with the response.

     2.c.2.b - Else if the names do match, but the GL cannot be deleted
               for other reasons, which the GLA does not wish to
               disclose, the GLA returns a response indicating
               cMCStatusInfoExt with cMCStatus.failed and
               otherInfo.extendedFailInfo.SKDFailInfo value of
               unspecified. Additionally, a signingTime attribute is
               included with the response. Actions beyond the scope of
               this document must then be taken to delete the GL from
               the GLA.

     2.c.2.c - Else if the names do match, the GLA returns a
               cMCStatusInfoExt indicating cMCStatus.success and a
               signingTime attribute (2 in Figure 4). The GLA ought not
               accept further requests for member additions, member
               deletions, or group rekeys for this GL.



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     2.c.2.c.1 - The GLA can apply confidentiality to the response by
                 encapsulating the SignedData.PKIResponse in an
                 EnvelopedData if the request was encapsulated in an
                 EnvelopedData (see section 3.2.1.2).

     2.c.2.c.2 - The GLA MAY optionally apply another SignedData over
                 the EnvelopedData (see section 3.2.1.2).

     3 - Upon receipt of the cMCStatusInfoExt response, the GLO checks
        the signingTime and verifies the GLA signature(s). If an
        additional SignedData and/or EnvelopedData encapsulates the
        response (see section 3.2.1.2 or 3.2.2), the GLO verifies the
        outer signature and/or decrypt the outer layer prior to
        verifying the signature on the inner most SignedData.

     3.a - If the signingTime attribute value is not within the locally
           accepted time window, the GLO MAY return a response
           indicating cMCStatus.failed and otherInfo.failInfo.badTime
           and a signingTime attribute.

     3.b - Else if signature processing continues and if the signatures
           verify, the GLO checks that one of the names in the
           certificate used to sign the response matches the name of
           the GL.

     3.b.1 - If the name of the GL does not match the name present in
            the certificate used to sign the message, the GLO should
            not believe the response.

     3.b.2 - Else if the name of the GL does match the name present in
            the certificate and:

     3.b.2.a - If the signatures verify and the response was
               cMCStatusInfoExt indicating cMCStatus.success, the GLO
               has successfully deleted the GL.

     3.b.2.b - Else if the signatures do verify and the response was
               cMCStatusInfoExt.cMCStatus.failed with any reason, the
               GLO can reattempt to delete the GL using the information
               provided in the response.

4.3. Add Members To GL

   To add members to GLs, either the GLO or prospective members use the
   glAddMember request. The GLA processes GLO and prospective GL member
   requests differently though. GLOs can submit the request at any time
   to add members to the GL, and the GLA, once it has verified the


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   request came from a registered GLO, should process it. If a
   prospective member sends the request, the GLA needs to determine how
   the GL is administered. When the GLO initially configured the GL,
   they set the GL to be unmanaged, managed, or closed (see section
   3.1.1). In the unmanaged case, the GLA merely processes the member's
   request. For the managed case, the GLA forwards the requests from the
   prospective members to the GLO for review. Where there are multiple
   GLOs for a GL, which GLO the request is forwarded to is beyond the
   scope of this document. The GLO reviews the request and either
   rejects it or submits a reformed request to the GLA. In the closed
   case, the GLA will not accept requests from prospective members. The
   following sections describe the processing for the GLO(s), GLA, and
   prospective GL members depending on where the glAddMeber request
   originated, either from a GLO or from prospective members. Figure 5
   depicts the protocol interactions for the three options. Note that
   the error messages are not depicted. Additionally, note that behavior
   for the optional transactionId, senderNonce, and recipientNonce CMC
   control attributes is not addressed in these procedures.

                   +-----+  2,B{A}              3  +----------+
                   | GLO | <--------+    +-------> | Member 1 |
                   +-----+          |    |         +----------+
                            1       |    |
                   +-----+ <--------+    |      3  +----------+
                   | GLA |  A            +-------> |   ...    |
                   +-----+ <-------------+         +----------+
                                         |
                                         |      3  +----------+
                                         +-------> | Member n |
                                                   +----------+

                      Figure 5 - Member Addition

   An important decision that needs to be made on a group by group basis
   is whether to rekey the group every time a new member is added.
   Typically, unmanaged GLs should not be rekeyed when a new member is
   added, as the overhead associated with rekeying the group becomes
   prohibitive, as the group becomes large. However, managed and closed
   GLs can be rekeyed to maintain the confidentiality of the traffic
   sent by group members. An option to rekeying managed or closed GLs
   when a member is added is to generate a new GL with a different group
   key. Group rekeying is discussed in sections 4.5 and 5.







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4.3.1. GLO Initiated Additions

   The process for GLO initiated glAddMember requests is as follows:

     1 - The GLO collects the pertinent information for the member(s) to
        be added (this may be done through an out of bands means). The
        GLO then sends a SignedData.PKIData.controlSequence with a
        separate glAddMember request for each member to the GLA (1 in
        Figure 5). The GLO includes: the GL name in glName, the
        member's name in glMember.glMemberName, the member's address in
        glMember.glMemberAddress, and the member's encryption
        certificate in glMember.certificates.pKC. The GLO can also
        include any attribute certificates associated with the member's
        encryption certificate in glMember.certificates.aC, and the
        certification path associated with the member's encryption and
        attribute certificates in glMember.certificates.certPath. The
        GLO MUST also include the signingTime attribute with this
        request.

     1.a - The GLO can optionally apply confidentiality to the request
           by encapsulating the SignedData.PKIData in an EnvelopedData
           (see section 3.2.1.2).

     1.b - The GLO can also optionally apply another SignedData over the
           EnvelopedData (see section 3.2.1.2).

     2 - Upon receipt of the request, the GLA checks the signingTime and
        verifies the signature on the inner most SignedData.PKIData. If
        an additional SignedData and/or EnvelopedData encapsulates the
        request (see section 3.2.1.2 or 3.2.2), the GLA verifies the
        outer signature and/or decrypt the outer layer prior to
        verifying the signature on the inner most SignedData.

     2.a - If the signingTime attribute value is not within the locally
           accepted time window, the GLA MAY return a response
           indicating cMCStatus.failed and otherInfo.failInfo.badTime
           and a signingTime attribute.

     2.b - Else if signature processing continues and if the signatures
           cannot be verified, the GLA returns a cMCStatusInfoExt
           response indicating cMCStatus.failed and
           otherInfo.failInfo.badMessageCheck. Additionally, a
           signingTime attribute is included with the response.

     2.c - Else if the signatures verify, the glAddMember request is
           included in a controlSequence with the glUseKEK request, and
           the processing in section 4.1 item 2.e is successfully


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           completed the GLA returns a cMCStatusInfoExt indicating
           cMCStatus.success and a signingTime attribute (2 in Figure
           5).

     2.c.1 - The GLA can apply confidentiality to the response by
            encapsulating the SignedData.PKIData in an EnvelopedData if
            the request was encapsulated in an EnvelopedData (see
            section 3.2.1.2).

     2.c.2 - The GLA can also optionally apply another SignedData over
            the EnvelopedData (see section 3.2.1.2).

     2.d - Else if the signatures verify and the GLAddMember request is
           not included in a controlSequence with the GLCreate request,
           the GLA makes sure the GL is supported by checking that the
           glName matches a glName stored on the GLA.

     2.d.1 - If the glName is not supported by the GLA, the GLA returns
            a response indicating cMCStatusInfoExt with
            cMCStatus.failed and otherInfo.extendedFailInfo.SKDFailInfo
            value of invalidGLName. Additionally, a signingTime
            attribute is included with the response.

     2.d.2 - Else if the glName is supported by the GLA, the GLA checks
            to see if the glMemberName is present on the GL.

     2.d.2.a - If the glMemberName is present on the GL, the GLA returns
               a response indicating cMCStatusInfoExt with
               cMCStatus.failed and
               otherInfo.extendedFailInfo.SKDFailInfo value of
               alreadyAMember. Additionally, a signingTime attribute is
               included with the response.

     2.d.2.b - Else if the glMemberName is not present on the GL, the
               GLA checks how the GL is administered.

     2.d.2.b.1 - If the GL is closed, the GLA checks that a registered
                 GLO signed the request by checking that one of the
                 names in the digital signature certificate used to
                 sign the request matches a registered GLO.

     2.d.2.b.1.a - If the names do not match, the GLA returns a response
                  indicating cMCStatusInfoExt with cMCStatus.failed and
                  otherInfo.extendedFailInfo.SKDFailInfo value of
                  noGLONameMatch. Additionally, a signingTime attribute
                  is included with the response.



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     2.d.2.b.1.b - Else if the names match, the GLA verifies the
                  member's encryption certificate.

     2.d.2.b.1.b.1 - If the member's encryption certificate cannot be
                     verified, the GLA can return a response indicating
                     cMCStatusInfoExt with cMCStatus.failed and
                     otherInfo.extendedFailInfo.SKDFailInfo value of
                     invalidCert to the GLO. Additionally, a
                     signingTime attribute is included with the
                     response. If the GLA does not return a
                     cMCStatusInfoExt.cMCStatus.failed response, the
                     GLA issues a glProvideCert request (see section
                     4.10).

     2.d.2.b.1.b.2 - Else if the member's certificate verifies, the GLA
                     returns a cMCStatusInfoExt indicating
                     cMCStatus.success and a signingTime attribute (2
                     in Figure 5). The GLA also takes administrative
                     actions, which are beyond the scope of this
                     document, to add the member to the GL stored on
                     the GLA. The GLA also distributes the shared KEK
                     to the member via the mechanism described in
                     section 5.

     2.d.2.b.1.b.2.a - The GLA applies confidentiality to the response
                       by encapsulating the SignedData.PKIData in an
                       EnvelopedData if the request was encapsulated in
                       an EnvelopedData (see section 3.2.1.2).

     2.d.2.b.1.b.2.b - The GLA can also optionally apply another
                       SignedData over the EnvelopedData (see section
                       3.2.1.2).

     2.d.2.b.2 - Else if the GL is managed, the GLA checks that either a
                 registered GLO or the prospective member signed the
                 request. For GLOs, one of the names in the certificate
                 used to sign the request needs to match a registered
                 GLO. For the prospective member, the name in
                 glMember.glMemberName needs to match one of the names
                 in the certificate used to sign the request.

     2.d.2.b.2.a - If the signer is neither a registered GLO nor the
                  prospective GL member, the GLA returns a response
                  indicating cMCStatusInfoExt with cMCStatus.failed and
                  otherInfo.extendedFailInfo.SKDFailInfo value of
                  noSpam. Additionally, a signingTime attribute is
                  included with the response.


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     2.d.2.b.2.b - Else if the signer is a registered GLO, the GLA
                  verifies the member's encryption certificate.

     2.d.2.b.2.b.1 - If the member's certificate cannot be verified, the
                     GLA can return a response indicating
                     cMCStatusInfoExt with cMCStatus.failed and
                     otherInfo.extendedFailInfo.SKDFailInfo value of
                     invalidCert. Additionally, a signingTime attribute
                     is included with the response. If the GLA does not
                     return a cMCStatus.failed response, the GLA MUST
                     issue a glProvideCert request (see section 4.10).

     2.d.2.b.2.b.2 - Else if the member's certificate verifies, the GLA
                     MUST return a cMCStatusInfoExt indicating
                     cMCStatus.success and a signingTime attribute to
                     the GLO (2 in Figure 5). The GLA also takes
                     administrative actions, which are beyond the scope
                     of this document, to add the member to the GL
                     stored on the GLA. The GLA also distributes the
                     shared KEK to the member via the mechanism
                     described in section 5. The GL policy may mandate
                     that the GL member's address be included in the GL
                     member's certificate.

     2.d.2.b.2.b.2.a - The GLA applies confidentiality to the response
                      by encapsulating the SignedData.PKIData in an
                      EnvelopedData if the request was encapsulated in
                      an EnvelopedData (see section 3.2.1.2).

     2.d.2.b.2.b.2.b - The GLA can also optionally apply another
                      SignedData over the EnvelopedData (see section
                      3.2.1.2).

     2.d.2.b.2.c - Else if the signer is the prospective member, the GLA
                      forwards the glAddMember request (see section
                      3.2.3) to a registered GLO (B{A} in Figure 5). If
                      there is more than one registered GLO, the GLO to
                      which the request is forwarded to is beyond the
                      scope of this document. Further processing of the
                      forwarded request by GLOs is addressed in 3 of
                      section 4.3.2.

     2.d.2.b.2.c.1 - The GLA applies confidentiality to the forwarded
                     request by encapsulating the SignedData.PKIData in
                     an EnvelopedData if the original request was
                     encapsulated in an EnvelopedData (see section
                     3.2.1.2).


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     2.d.2.b.2.c.2 - The GLA can also optionally apply another
                     SignedData over the EnvelopedData (see section
                     3.2.1.2).

     2.d.2.b.3 - Else if the GL is unmanaged, the GLA checks that either
                 a registered GLO or the prospective member signed the
                 request. For GLOs, one of the names in the certificate
                 used to sign the request needs tp match the name of a
                 registered GLO. For the prospective member, the name
                 in glMember.glMemberName needs to match one of the
                 names in the certificate used to sign the request.

     2.d.2.b.3.a - If the signer is neither a registered GLO nor the
                  prospective member, the GLA returns a response
                  indicating cMCStatusInfoExt with cMCStatus.failed and
                  otherInfo.extendedFailInfo.SKDFailInfo value of
                  noSpam. Additionally, a signingTime attribute is
                  included with the response.

     2.d.2.b.3.b - Else if the signer is either a registered GLO or the
                  prospective member, the GLA verifies the member's
                  encryption certificate.

     2.d.2.b.3.b.1 - If the member's certificate cannot be verified, the
                     GLA can return a response indicating
                     cMCStatusInfoExt with cMCStatus.failed and
                     otherInfo.extendedFailInfo.SKDFailInfo value of
                     invalidCert and a signingTime attribute to either
                     the GLO or the prospective member depending on
                     where the request originated. If the GLA does not
                     return a cMCStatus.failed response, the GLA issues
                     a glProvideCert request (see section 4.10) to
                     either the GLO or prospective member depending on
                     where the request originated.

     2.d.2.b.3.b.2 - Else if the member's certificate verifies, the GLA
                     returns a cMCStatusInfoExt indicating
                     cMCStatus.success and a signingTime attribute to
                     the GLO (2 in Figure 5) if the GLO signed the
                     request and to the GL member (3 in Figure 5) if
                     the GL member signed the request. The GLA also
                     takes administrative actions, which are beyond the
                     scope of this document, to add the member to the
                     GL stored on the GLA. The GLA also distributes the
                     shared KEK to the member via the mechanism
                     described in section 5.



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     2.d.2.b.3.b.2.a - The GLA applies confidentiality to the response
                      by encapsulating the SignedData.PKIData in an
                      EnvelopedData if the request was encapsulated in
                      an EnvelopedData (see section 3.2.1.2).

     2.d.2.b.3.b.2.b - The GLA can also optionally apply another
                      SignedData over the EnvelopedData (see section
                      3.2.1.2).

     3 - Upon receipt of the cMCStatusInfoExt response, the GLO checks
        the signingTime and verifies the GLA signature(s). If an
        additional SignedData and/or EnvelopedData encapsulates the
        response (see section 3.2.1.2 or 3.2.2), the GLO verifies the
        outer signature and/or decrypt the outer layer prior to
        verifying the signature on the inner most SignedData.

     3.a - If the signingTime attribute value is not within the locally
           accepted time window, the GLO MAY return a response
           indicating cMCStatus.failed and otherInfo.failInfo.badTime
           and a signingTime attribute.

     3.b - Else if signature processing continues and if the signatures
           verify, the GLO checks that one of the names in the
           certificate used to sign the response matches the name of
           the GL.

     3.b.1 - If the name of the GL does not match the name present in
            the certificate used to sign the message, the GLO should
            not believe the response.

     3.b.2 - Else if the name of the GL matches the name present in the
            certificate and:

     3.b.2.a - If the signatures verify and the response is
               cMCStatusInfoExt indicating cMCStatus.success, the GLA
               has added the member to the GL. If member was added to a
               managed list and the original request was signed by the
               member, the GLO sends a
               cMCStatusInfoExt.cMCStatus.success and a signingTime
               attribute to the GL member.

     3.b.2.b - Else if the GLO received a
               cMCStatusInfoExt.cMCStatus.failed with any reason, the
               GLO can reattempt to add the member to the GL using the
               information provided in the response.




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     4 - Upon receipt of the cMCStatusInfoExt response, the prospective
        member checks the signingTime and verifies the GLA signatures
        or GLO signatures. If an additional SignedData and/or
        EnvelopedData encapsulates the response (see section 3.2.1.2 or
        3.2.2), the GLO verifies the outer signature and/or decrypt the
        outer layer prior to verifying the signature on the inner most
        SignedData.

     4.a - If the signingTime attribute value is not within the locally
           accepted time window, the prospective member MAY return a
           response indicating cMCStatus.failed and
           otherInfo.failInfo.badTime and a signingTime attribute.

     4.b - Else if signature processing continues and if the signatures
           verify, the GL member checks that one of the names in the
           certificate used to sign the response matches the name of
           the GL.

     4.b.1 - If the name of the GL does not match the name present in
            the certificate used to sign the message, the GL member
            should not believe the response.

     4.b.2 - Else if the name of the GL matches the name present in the
            certificate and:

     4.b.2.a - If the signatures verify, the prospective member has been
               added to the GL.

     4.b.2.b - Else if the prospective member received a
               cMCStatusInfoExt.cMCStatus.failed, for any reason, the
               prospective member MAY reattempt to add themselves to the
               GL using the information provided in the response.

4.3.2. Prospective Member Initiated Additions

   The process for prospective member initiated glAddMember requests is
   as follows:

     1 - The prospective GL member sends a
        SignedData.PKIData.controlSequence.glAddMember request to the
        GLA (A in Figure 5). The prospective GL member includes: the GL
        name in glName, their name in glMember.glMemberName, their
        address in glMember.glMemberAddress, and their encryption
        certificate in glMember.certificates.pKC. The prospective GL
        member can also include any attribute certificates associated
        with their encryption certificate in glMember.certificates.aC,
        and the certification path associated with their encryption and


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        attribute certificates in glMember.certificates.certPath. The
        prosepective member MUST also include the signingTime attribute
        with this request.

     1.a - The prospective GL member can optionally apply
           confidentiality to the request by encapsulating the
           SignedData.PKIData in an EnvelopedData (see section
           3.2.1.2).

     1.b - The prospective GL member MAY optionally apply another
           SignedData over the EnvelopedData (see section 3.2.1.2).

     2 - Upon receipt of the request, the GLA verifies the request as
        per 2 in section 4.3.1.

     3 - Upon receipt of the forwarded request, the GLO checks the
        signingTime and verifies the prospective GL member signature on
        the inner most SignedData.PKIData and the GLA signature on the
        outer layer. If an EnvelopedData encapsulates the inner most
        layer (see section 3.2.1.2 or 3.2.2), the GLO decrypts the
        outer layer prior to verifying the signature on the inner most
        SignedData.

        Note: For cases where the GL is closed and either a) a
        prospective member sends directly to the GLO or b) the GLA has
        mistakenly forwarded the request to the GLO, the GLO should
        first determine whether to honor the request.

     3.a - If the signingTime attribute value is not within the locally
           accepted time window, the GLO MAY return a response
           indicating cMCStatus.failed and otherInfo.failInfo.badTime.

     3.b - Else if signature processing continues and if the signatures
           verify, the GLO checks to make sure one of the names in the
           certificate used to sign the request matches the name in
           glMember.glMemberName.

     3.b.1 - If the names do not match, the GLO sends a
            SignedData.PKIResponse.controlSequence message back to the
            prospective member with cMCStatusInfoExt.cMCStatus.failed
            indicating why the prospective member was denied in
            cMCStausInfo.statusString. This stops people from adding
            people to GLs without their permission. Additionally, a
            signingTime attribute is included with the response.

     3.b.2 - Else if the names match, the GLO determines whether the
            prospective member is allowed to be added. The mechanism is


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            beyond the scope of this document; however, the GLO should
            check to see that the glMember.glMemberName is not already
            on the GL.

     3.b.2.a - If the GLO determines the prospective member is not
               allowed to join the GL, the GLO can return a
               SignedData.PKIResponse.controlSequence message back to
               the prospective member with
               cMCStatusInfoExt.cMCtatus.failed indicating why the
               prospective member was denied in cMCStatus.statusString.
               Additionally, a signingTime attribute is included with
               the response.

     3.b.2.b - Else if GLO determines the prospective member is allowed
               to join the GL, the GLO verifies the member's encryption
               certificate.

     3.b.2.b.1 - If the member's certificate cannot be verified, the GLO
                 returns a SignedData.PKIResponse.controlSequence back
                 to the prospective member with
                 cMCStatusInfoExt.cMCtatus.failed indicating that the
                 member's encryption certificate did not verify in
                 cMCStatus.statusString. Additionally, a signingTime
                 attribute is included with the response. If the GLO
                 does not return a cMCStatusInfoExt response, the GLO
                 sends a
                 SignedData.PKIData.controlSequence.glProvideCert
                 message to the prospective member requesting a new
                 encryption certificate (see section 4.10).

     3.b.2.b.2 - Else if the member's certificate verifies, the GLO
                 resubmits the glAddMember request (see section 3.2.5)
                 to the GLA (1 in Figure 5).

     3.b.2.b.2.a - The GLO applies confidentiality to the new
                  GLAddMember request by encapsulating the
                  SignedData.PKIData in an EnvelopedData if the initial
                  request was encapsulated in an EnvelopedData (see
                  section 3.2.1.2).

     3.b.2.b.2.b - The GLO can also optionally apply another SignedData
                  over the EnvelopedData (see section 3.2.1.2).

     4 - Processing continues as in 2 of section 4.3.1.





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4.4. Delete Members From GL

   To delete members from GLs, either the GLO or members to be removed
   use the glDeleteMember request. The GLA processes GLO and members
   requesting their own removal make requests differently. The GLO can
   submit the request at any time to delete members from the GL, and the
   GLA, once it has verified the request came from a registered GLO,
   should delete the member. If a member sends the request, the GLA
   needs to determine how the GL is administered. When the GLO initially
   configured the GL, they set the GL to be unmanaged, managed, or
   closed (see section 3.1.1). In the unmanaged case, the GLA merely
   processes the member's request. For the managed case, the GLA
   forwards the requests from the member to the GLO for review. Where
   there are multiple GLOs for a GL, which GLO the request is forwarded
   to is beyond the scope of this document. The GLO reviews the request
   and either rejects it or submits a reformed request to the GLA. In
   the closed case, the GLA will not accept requests from members. The
   following sections describe the processing for the GLO(s), GLA, and
   GL members depending on where the request originated, either from a
   GLO or from members wanting to be removed. Figure 6 depicts the
   protocol interactions for the three options. Note that the error
   messages are not depicted. Additionally, behavior for the optional
   transactionId, senderNonce, and recipientNonce CMC control attributes
   is not addressed in these procedures.

                   +-----+  2,B{A}              3  +----------+
                   | GLO | <--------+    +-------> | Member 1 |
                   +-----+          |    |         +----------+
                            1       |    |
                   +-----+ <--------+    |      3  +----------+
                   | GLA |  A            +-------> |   ...    |
                   +-----+ <-------------+         +----------+
                                         |
                                         |      3  +----------+
                                         +-------> | Member n |
                                                   +----------+

                      Figure 6 - Member Deletion

   If the member is not removed from the GL, they will continue to
   receive and be able to decrypt data protected with the shared KEK and
   will continue to receive rekeys. For unmanaged lists, there is no
   point to a group rekey because there is no guarantee that the member
   requesting to be removed has not already added themselves back on the
   GL under a different name. For managed and closed GLs, the GLO needs
   to take steps to ensure the member being deleted is not on the GL
   twice. After ensuring this, managed and closed GLs can be rekeyed to


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   maintain the confidentiality of the traffic sent by group members. If
   the GLO is sure the member has been deleted the group rekey mechanism
   can be used to distribute the new key (see sections 4.5 and 5).

4.4.1. GLO Initiated Deletions

   The process for GLO initiated glDeleteMember requests is as follows:

     1 - The GLO collects the pertinent information for the member(s) to
        be deleted (this can be done through an out of bands means).
        The GLO then sends a SignedData.PKIData.controlSequence with a
        separate glDeleteMember request for each member to the GLA (1
        in Figure 6). The GLO MUST include: the GL name in glName and
        the member's name in glMemberToDelete. If the GL from which the
        member is being deleted in a closed or managed GL, the GLO MUST
        also generate a glRekey request and include it with the
        glDeletemember request (see section 4.5). The GLO MUST also
        include the signingTime attribute with this request.

     1.a - The GLO can optionally apply confidentiality to the request
           by encapsulating the SignedData.PKIData in an EnvelopedData
           (see section 3.2.1.2).

     1.b - The GLO can also optionally apply another SignedData over the
           EnvelopedData (see section 3.2.1.2).

     2 - Upon receipt of the request, the GLA checks the signingTime
        attribute and verifies the signature on the inner most
        SignedData.PKIData. If an additional SignedData and/or
        EnvelopedData encapsulates the request (see section 3.2.1.2 or
        3.2.2), the GLA verifies the outer signature and/or decrypt the
        outer layer prior to verifying the signature on the inner most
        SignedData.

     2.a - If the signingTime attribute value is not within the locally
           accepted time window, the GLA MAY return a response
           indicating cMCStatus.failed and otherInfo.failInfo.badTime
           and a signingTime attribute.

     2.b - Else if signature processing continues and if the signatures
           cannot be verified, the GLA returns a cMCStatusInfoExt
           response indicating cMCStatus.failed and
           otherInfo.failInfo.badMessageCheck. Additionally, a
           signingTime attribute is included with the response.





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     2.c - Else if the signatures verify, the GLA makes sure the GL is
           supported by the GLA by checking that the glName matches a
           glName stored on the GLA.

     2.c.1 - If the glName is not supported by the GLA, the GLA returns
            a response indicating cMCStatusInfoExt with
            cMCStatus.failed and otherInfo.extendedFailInfo.SKDFailInfo
            value of invalidGLName. Additionally, a signingTime
            attribute is included with the response.

     2.c.2 - Else if the glName is supported by the GLA, the GLA checks
            to see if the glMemberName is present on the GL.

     2.c.2.a - If the glMemberName is not present on the GL, the GLA
               returns a response indicating cMCStatusInfoExt with
               cMCStatus.failed and
               otherInfo.extendedFailInfo.SKDFailInfo value of
               notAMember. Additionally, a signingTime attribute is
               included with the response.

     2.c.2.b - Else if the glMemberName is already on the GL, the GLA
               checks how the GL is administered.

     2.c.2.b.1 - If the GL is closed, the GLA checks that the registered
                GLO signed the request by checking that one of the
                names in the digital signature certificate used to sign
                the request matches the registered GLO.

     2.c.2.b.1.a - If the names do not match, the GLA returns a response
                  indicating cMCStatusInfoExt with cMCStatus.failed and
                  otherInfo.extendedFailInfo.SKDFailInfo value of
                  closedGL. Additionally, a signingTime attribute is
                  included with the response.

     2.c.2.b.1.b - Else if the names do match, the GLA returns a
                  cMCStatusInfoExt.cMCStatus.success and a signingTime
                  attribute (2 in Figure 5). The GLA also takes
                  administrative actions, which are beyond the scope of
                  this document, to delete the member with the GL
                  stored on the GLA. Note that he GL also needs to be
                  rekeyed as described in section 5.

     2.c.2.b.1.b.1 - The GLA applies confidentiality to the response by
                     encapsulating the SignedData.PKIData in an
                     EnvelopedData if the request was encapsulated in
                     an EnvelopedData (see section 3.2.1.2).



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     2.c.2.b.1.b.2 - The GLA can also optionally apply another
                     SignedData over the EnvelopedData (see section
                     3.2.1.2).

     2.c.2.b.2 - Else if the GL is managed, the GLA checks that either a
                 registered GLO or the prospective member signed the
                 request. For GLOs, one of the names in the certificate
                 used to sign the request needs to match a registered
                 GLO. For the prospective member, the name in
                 glMember.glMemberName needs to match one of the names
                 in the certificate used to sign the request.

     2.c.2.b.2.a - If the signer is neither a registered GLO nor the
                  prospective GL member, the GLA returns a response
                  indicating cMCStatusInfoExt with cMCStatus.failed and
                  otherInfo.extendedFailInfo.SKDFailInfo value of
                  noSpam. Additionally, a signingTime attribute is
                  included with the response.

     2.c.2.b.2.b - Else if the signer is a registered GLO, the GLA
                  returns a cMCStatusInfoExt.cMCStatus.success and a
                  signingTime attribute(2 in Figure 6). The GLA also
                  takes administrative actions, which are beyond the
                  scope of this document, to delete the member with the
                  GL stored on the GLA. Note that the GL will also be
                  rekeyed as described in section 5.

     2.c.2.b.2.b.1 - The GLA applies confidentiality to the response by
                     encapsulating the SignedData.PKIData in an
                     EnvelopedData if the request was encapsulated in
                     an EnvelopedData (see section 3.2.1.2).

     2.c.2.b.2.b.2 - The GLA can also optionally apply another
                     SignedData over the EnvelopedData (see section
                     3.2.1.2).

     2.c.2.b.2.c - Else if the signer is the prospective member, the GLA
                  forwards the glDeleteMember request (see section
                  3.2.3) to the GLO (B{A} in Figure 6). If there is
                  more than one registered GLO, the GLO to which the
                  request is forwarded to is beyond the scope of this
                  document. Further processing of the forwarded request
                  by GLOs is addressed in 3 of section 4.4.2.

     2.c.2.b.2.c.1 - The GLA applies confidentiality to the forwarded
                  request by encapsulating the SignedData.PKIData in an



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                  EnvelopedData if the request was encapsulated in an
                  EnvelopedData (see section 3.2.1.2).

     2.c.2.b.2.c.2 - The GLA can also optionally apply another
                  SignedData over the EnvelopedData (see section
                  3.2.1.2).

     2.c.2.b.3 - Else if the GL is unmanaged, the GLA checks that either
                 a registered GLO or the prospective member signed the
                 request. For GLOs, one of the names in the certificate
                 used to sign the request needs to match the name of a
                 registered GLO. For the prospective member, the name
                 in glMember.glMemberName needs to match one of the
                 names in the certificate used to sign the request.

     2.c.2.b.3.a - If the signer is neither the GLO nor the prospective
                  member, the GLA returns a response indicating
                  cMCStatusInfoExt with cMCStatus.failed and
                  otherInfo.extendedFailInfo.SKDFailInfo value of
                  noSpam. Additionally, a signingTime attribute is
                  included with the response.

     2.c.2.b.3.b - Else if the signer is either a registered GLO or the
                  member, the GLA returns a
                  cMCStatusInfoExt.cMCStatus.success and a signingTime
                  attribute to the GLO (2 in Figure 6) if the GLO
                  signed the request and to the GL member (3 in Figure
                  6) if the GL member signed the request. The GLA also
                  takes administrative actions, which are beyond the
                  scope of this document, to delete the member with the
                  GL stored on the GLA.

     2.c.2.b.3.b.1 - The GLA applies confidentiality to the response by
                     encapsulating the SignedData.PKIData in an
                     EnvelopedData if the request was encapsulated in
                     an EnvelopedData (see section 3.2.1.2).

     2.c.2.b.3.b.2 - The GLA can also optionally apply another
                     SignedData over the EnvelopedData (see section
                     3.2.1.2).

     3 - Upon receipt of the cMCStatusInfoExt response, the GLO checks
        the signingTime and verifies the GLA signatures. If an
        additional SignedData and/or EnvelopedData encapsulates the
        response (see section 3.2.1.2 or 3.2.2), the GLO verifies the
        outer signature and/or decrypt the outer layer prior to
        verifying the signature on the inner most SignedData.


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     3.a - If the signingTime attribute value is not within the locally
           accepted time window, the GLO MAY return a response
           indicating cMCStatus.failed and otherInfo.failInfo.badTime
           and a signingTime attribute.

     3.b - Else if signature processing continues and if the signatures
           do verify, the GLO checks that one of the names in the
           certificate used to sign the response matches the name of
           the GL.

     3.b.1 - If the name of the GL does not match the name present in
            the certificate used to sign the message, the GLO should
            not believe the response.

     3.b.2 - Else if the name of the GL matches the name present in the
            certificate and:

     3.b.2.a - If the signatures verify and the response is
               cMCStatusInfoExt.cMCStatus.success, the GLO has deleted
               the member from the GL. If member was deleted from a
               managed list and the original request was signed by the
               member, the GLO sends a
               cMCStatusInfoExt.cMCStatus.success and a signingTime
               attribute to the GL member.

     3.b.2.b - Else if the GLO received a
               cMCStatusInfoExt.cMCStatus.failed with any reason, the
               GLO may reattempt to delete the member from the GL using
               the information provided in the response.

     4 - Upon receipt of the cMCStatusInfoExt response, the member
        checks the signingTime and verifies the GLA signature(s) or GLO
        signature(s). If an additional SignedData and/or EnvelopedData
        encapsulates the response (see section 3.2.1.2 or 3.2.2), the
        GLO verifies the outer signature and/or decrypt the outer layer
        prior to verifying the signature on the inner most SignedData.

     4.a - If the signingTime attribute value is not within the locally
           accepted time window, the prospective member MAY return a
           response indicating cMCStatus.failed and
           otherInfo.failInfo.badTime and a signingTime attribute.

     4.b - Else if signature processing continues and if the signatures
           verify, the GL member checks that one of the names in the
           certificate used to sign the response matches the name of
           the GL.



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     4.b.1 - If the name of the GL does not match the name present in
            the certificate used to sign the message, the GL member
            should not believe the response.

     4.b.2 - Else if the name of the GL matches the name present in the
            certificate and:

     4.b.2.a - If the signature(s) verify, the member has been deleted
               from the GL.

     4.b.2.b - Else if the member received a
               cMCStatusInfoExt.cMCStatus.failed with any reason, the
               member can reattempt to delete themselves from the GL
               using the information provided in the response.

4.4.2. Member Initiated Deletions

   The process for member initiated deletion of their own membership
   using the glDeleteMember requests is as follows:

     1 - The member sends a
        SignedData.PKIData.controlSequence.glDeleteMember request to
        the GLA (A in Figure 6). The member includes: the name of the
        GL in glName and their own name in glMemberToDelete. The GL
        member MUST also include the signingTime attribute with this
        request.

     1.a - The member can optionally apply confidentiality to the
           request by encapsulating the SignedData.PKIData in an
           EnvelopedData (see section 3.2.1.2).

     1.b - The member can also optionally apply another SignedData over
           the EnvelopedData (see section 3.2.1.2).

     2 - Upon receipt of the request, the GLA verifies the request as
        per 2 in section 4.4.1.

     3 - Upon receipt of the forwarded request, the GLO checks the
        signingTime and verifies the member signature on the inner most
        SignedData.PKIData and the GLA signature on the outer layer. If
        an EnvelopedData encapsulates the inner most layer (see section
        3.2.1.2 or 3.2.2), the GLO decrypts the outer layer prior to
        verifying the signature on the inner most SignedData. Note: For
        cases where the GL is closed and either (a) a prospective
        member sends directly to the GLO or (b) the GLA has mistakenly
        forwarded the request to the GLO, the GLO should first
        determine whether to honor the request.


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     3.a - If the signingTime attribute value is not within the locally
           accepted time window, the GLO MAY return a response
           indicating cMCStatus.failed and otherInfo.failInfo.badTime
           and a signingTime attribute.

     3.b - Else if signature processing continues if the signatures
           cannot be verified, the GLO returns a cMCStatusInfoExt
           response indicating cMCStatus.failed and
           otherInfo.failInfo.badMessageCheck and a signingTime
           attribute.

     3.c - Else if the signatures verify, the GLO checks to make sure
           one of the names in the certificates used to sign the
           request matches the name in glMemberToDelete.

     3.c.1 - If the names match, the GLO sends a
            SignedData.PKIResponse.controlSequence message back to the
            prospective member with cMCStatusInfoExt.cMCtatus.failed
            indicating why the prospective member was denied in
            cMCStatusInfoExt.statusString. This stops people from
            adding people to GLs without their permission.
            Additionally, a signingTime attribute is included with the
            response.

     3.c.2 - Else if the names match, the GLO resubmits the
            glDeleteMember request (see section 3.2.5) to the GLA (1 in
            Figure 6). The GLO makes sure the glMemberName is already
            on the GL. The GLO also generates a glRekey request and
            include it with the GLDeleteMember request (see section
            4.5).

     3.c.2.a - The GLO applies confidentiality to the new GLDeleteMember
               request by encapsulating the SignedData.PKIData in an
               EnvelopedData if the initial request was encapsulated in
               an EnvelopedData (see section 3.2.1.2).

     3.c.2.b - The GLO can also optionally apply another SignedData over
               the EnvelopedData (see section 3.2.1.2).

     4 - Further processing is as in 2 of section 4.4.1.









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4.5. Request Rekey Of GL

   From time to time, the GL will need to be rekeyed. Some situations
   follow:

     - When a member is removed from a closed or managed GL. In this
       case, the PKIData.controlSequence containing the glDeleteMember
       ought to contain a glRekey request.

     - Depending on policy, when a member is removed from an unmanaged
       GL. If the policy is to rekey the GL, the
       PKIData.controlSequence containing the glDeleteMember could also
       contain a glRekey request or an out of bands means could be used
       to tell the GLA to rekey the GL. Rekeying of unmanaged GLs when
       members are deleted is not advised.

     - When the current shared KEK has been compromised.

     - When the current shared KEK is about to expire. Consider two
       cases:

       - If the GLO controls the GL rekey, the GLA should not assume
        that a new shared KEK should be distributed, but instead wait
        for the glRekey message.

       - If the GLA controls the GL rekey, the GLA should initiate a
        glKey message as specified in section 5.

   If the generationCounter (see section 3.1.1) is set to a value
   greater than one (1) and the GLO controls the GL rekey, the GLO may
   generate a glRekey any time before the last shared KEK has expired.
   To be on the safe side, the GLO ought to request a rekey one (1)
   duration before the last shared KEK expires.

   The GLA and GLO are the only entities allowed to initiate a GL rekey.
   The GLO indicated whether they are going to control rekeys or whether
   the GLA is going to control rekeys when they assigned the shared KEK
   to GL (see section 3.1.1). The GLO initiates a GL rekey at any time.
   The GLA can be configured to automatically rekey the GL prior to the
   expiration of the shared KEK (the length of time before the
   expiration is an implementation decision). The GLA can also
   automatically rekey GLs that have been compromised, but this is
   covered in section 5. Figure 7 depicts the protocol interactions to
   request a GL rekey. Note that error messages are not depicted.
   Additionally, behavior for the optional transactionId, senderNonce,
   and recipientNonce CMC control attributes is not addressed in these
   procedures.


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                     +-----+  1   2,A  +-----+
                     | GLA | <-------> | GLO |
                     +-----+           +-----+

                        Figure 7 - GL Rekey Request

4.5.1. GLO Initiated Rekey Requests

   The process for GLO initiated glRekey requests is as follows:

     1 - The GLO sends a SignedData.PKIData.controlSequence.glRekey
        request to the GLA (1 in Figure 7). The GLO includes the
        glName. If glAdministration and glKeyNewAttributes are omitted
        then there is no change from the previously registered GL
        values for these fields. If the GLO wants to force a rekey for
        all outstanding shared KEKs it includes the glRekeyAllGLKeys
        set to TRUE. The GLO MUST also include a signingTime attribute
        is included with this request.

     1.a - The GLO can optionally apply confidentiality to the request
           by encapsulating the SignedData.PKIData in an EnvelopedData
           (see section 3.2.1.2).

     1.b - The GLO can also optionally apply another SignedData over the
           EnvelopedData (see section 3.2.1.2).

     2 - Upon receipt of the request, the GLA checks the signingTime and
        verifies the signature on the inner most SignedData.PKIData. If
        an additional SignedData and/or EnvelopedData encapsulates the
        request (see section 3.2.1.2 or 3.2.2), the GLA verifies the
        outer signature and/or decrypt the outer layer prior to
        verifying the signature on the inner most SignedData.

     2.a - If the signingTime attribute value is not within the locally
           accepted time window, the GLA MAY return a response
           indicating cMCStatus.failed and otherInfo.failInfo.badTime
           and a signingTime attribute.

     2.b - Else if signature processing continues and if the signatures
           do not verify, the GLA returns a cMCStatusInfoExt response
           indicating cMCStatus.failed and
           otherInfo.failInfo.badMessageCheck. Additionally, a
           signingTime attribute is included with the response.

     2.c - Else if the signatures do verify, the GLA makes sure the GL
           is supported by the GLA by checking that the glName matches
           a glName stored on the GLA.


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     2.c.1 - If the glName present does not match a GL stored on the
            GLA, the GLA returns a response indicating cMCStatusInfoExt
            with cMCStatus.failed and
            otherInfo.extendedFailInfo.SKDFailInfo value of
            invalidGLName. Additionally, a signingTime attribute is
            included with the response.

     2.c.2 - Else if the glName present matches a GL stored on the GLA,
            the GLA checks that a registered GLO signed the request by
            checking that one of the names in the certificate used to
            sign the request is a registered GLO.

     2.c.2.a - If the names do not match, the GLA returns a response
               indicating cMCStatusInfoExt with cMCStatus.failed and
               otherInfo.extendedFailInfo.SKDFailInfo value of
               noGLONameMatch. Additionally, a signingTime attribute is
               included with the response.

     2.c.2.b - Else if the names match, the GLA checks the
               glNewKeyAttribute values.

     2.c.2.b.1 - If the new value for requestedAlgorithm is not
                 supported, the GLA returns a response indicating
                 cMCStatusInfoExt with cMCStatus.failed and
                 otherInfo.extendedFailInfo.SKDFailInfo value of
                 unsupportedAlgorithm. Additionally, a signingTime
                 attribute is included with the response.

     2.c.2.b.2 - Else if the new value duration is not supportable,
                 determining this is beyond the scope this document,
                 the GLA returns a response indicating cMCStatusInfoExt
                 with cMCStatus.failed and
                 otherInfo.extendedFailInfo.SKDFailInfo value of
                 unsupportedDuration. Additionally, a signingTime
                 attribute is included with the response.

     2.c.2.b.3 - Else if the GL is not supportable for other reasons,
                 which the GLA does not wish to disclose, the GLA
                 returns a response indicating cMCStatusInfoExt with
                 cMCStatus.failed and
                 otherInfo.extendedFailInfo.SKDFailInfo value of
                 unspecified. Additionally, a signingTime attribute is
                 included with the response.

     2.c.2.b.4 - Else if the new requestedAlgorithm and duration are
                 supportable or the glNewKeyAttributes was omitted, the
                 GLA returns a cMCStatusInfoExt.cMCStatus.success and a


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                 sigingTime attribute (2 in Figure 7). The GLA also
                 uses the glKey message to distribute the rekey shared
                 KEK (see section 5).

     2.c.2.b.4.a - The GLA applies confidentiality to response by
                  encapsulating the SignedData.PKIData in an
                  EnvelopedData if the request was encapsulated in an
                  EnvelopedData (see section 3.2.1.2).

     2.c.2.b.4.b - The GLA can also optionally apply another SignedData
                  over the EnvelopedData (see section 3.2.1.2).

     3 - Upon receipt of the cMCStatusInfoExt response, the GLO checks
        the signingTime and verifies the GLA signature(s). If an
        additional SignedData and/or EnvelopedData encapsulates the
        forwarded response (see section 3.2.1.2 or 3.2.2), the GLO
        verifies the outer signature and/or decrypt the forwarded
        response prior to verifying the signature on the inner most
        SignedData.

     3.a - If the signingTime attribute value is not within the locally
           accepted time window, the GLA MAY return a response
           indicating cMCStatus.failed and otherInfo.failInfo.badTime
           and a signingTime attribute.

     3.b - Else if signature processing continues and if the signatures
           verify, the GLO checks that one of the names in the
           certificate used to sign the response matches the name of
           the GL.

     3.b.1 - If the name of the GL does not match the name present in
            the certificate used to sign the message, the GLO should
            not believe the response.

     3.b.2 - Else if the name of the GL matches the name present in the
            certificate and:

     3.b.2.a - If the signatures verify and the response is
               cMCStatusInfoExt.cMCStatus.success, the GLO has
               successfully rekeyed the GL.

     3.b.2.b - Else if the GLO received a
               cMCStatusInfoExt.cMCStatus.failed with any reason, the
               GLO can reattempt to rekey the GL using the information
               provided in the response.




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4.5.2. GLA Initiated Rekey Requests

   If the GLA is in charge of rekeying the GL the GLA will automatically
   issue a glKey message (see section 5). In addition the GLA will
   generate a cMCStatusInfoExt to indicate to the GL that a successful
   rekey has occurred. The process for GLA initiated rekey is as
   follows:

     1 - The GLA generates for all GLOs a
        SignedData.PKIData.controlSequence.cMCStatusInfoExt.cMCStatus.
        success and includes a signingTime attribute (A in Figure 7).

     1.a - The GLA can optionally apply confidentiality to the request
           by encapsulating the SignedData.PKIData in an EnvelopedData
           (see section 3.2.1.2).

     1.b - The GLA can also optionally apply another SignedData over the
           EnvelopedData (see section 3.2.1.2).

     2 - Upon receipt of the cMCStatusInfoExt.cMCStatus.success
        response, the GLO checks the signingTime and verifies the GLA
        signature(s). If an additional SignedData and/or EnvelopedData
        encapsulates the forwarded response (see section 3.2.1.2 or
        3.2.2), the GLO MUST verify the outer signature and/or decrypt
        the outer layer prior to verifying the signature on the inner
        most SignedData.

     2.a - If the signingTime attribute value is not within the locally
           accepted time window, the GLO MAY return a response
           indicating cMCStatus.failed and otherInfo.failInfo.badTime
           and a signingTime attribute.

     2.b - Else if signature processing continues and if the signatures
           verify, the GLO checks that one of the names in the
           certificate used to sign the response matches the name of
           the GL.

     2.b.1 - If the name of the GL does not match the name present in
            the certificate used to sign the message, the GLO ought not
            believe the response.

     2.b.2 - Else if the name of the GL does match the name present in
            the certificate and and the response is
            cMCStatusInfoExt.cMCStatus.success, the GLO knows the GLA
            has successfully rekeyed the GL.




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4.6. Change GLO

   Management of managed and closed GLs can become difficult for one GLO
   if the GL membership grows large. To support distributing the
   workload, GLAs support having GLs be managed by multiple GLOs. The
   glAddOwner and glRemoveOwner messages are designed to support adding
   and removing registered GLOs. Figure 8 depicts the protocol
   interactions to send glAddOwner and glRemoveOwner messages and the
   resulting response messages. Note that error messages are not shown.
   Additionally, behavior for the optional transactionId, senderNonce,
   and recipientNonce CMC control attributes is not addressed in these
   procedures.

                         +-----+   1    2  +-----+
                         | GLA | <-------> | GLO |
                         +-----+           +-----+

                    Figure 8 - GLO Add & Delete Owners

   The process for glAddOwner and glDeleteOwner is as follows:

     1 - The GLO sends a SignedData.PKIData.controlSequence.glAddOwner
        or glRemoveOwner request to the GLA (1 in Figure 8). The GLO
        includes: the GL name in glName, the name and address of the
        GLO in glOwnerName and glOwnerAddress, respectively. The GLO
        MUST also include the signingTime attribute with this request.

     1.a - The GLO can optionally apply confidentiality to the request
           by encapsulating the SignedData.PKIData in an EnvelopedData
           (see section 3.2.1.2).

     1.b - The GLO can also optionally apply another SignedData over the
           EnvelopedData (see section 3.2.1.2).

     2 - Upon receipt of the glAddOwner or glRemoveOwner request, the
        GLA checks the signingTime and verifies the GLO signature(s).
        If an additional SignedData and/or EnvelopedData encapsulates
        the request (see section 3.2.1.2 or 3.2.2), the GLA verifies
        the outer signature and/or decrypt the outer layer prior to
        verifying the signature on the inner most SignedData.

     2.a - If the signingTime attribute value is not within the locally
           accepted time window, the GLA MAY return a response
           indicating cMCStatus.failed and otherInfo.failInfo.badTime
           and a signingTime attribute.




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     2.b - Else if signature processing continues and if the signatures
           cannot verified, the GLA returns a cMCStatusInfoExt response
           indicating cMCStatus.failed and
           otherInfo.failInfo.badMessageCheck. Additionally, a
           signingTime attribute is included with the response.

     2.c - Else if the signatures verify, the GLA makes sure the GL is
           supported by checking that the glName matches a glName
           stored on the GLA.

     2.c.1 - If the glName is not supported by the GLA, the GLA returns
            a response indicating cMCStatusInfoExt with
            cMCStatus.failed and otherInfo.extendedFailInfo.SKDFailInfo
            value of invalidGLName. Additionally, a signingTime
            attribute is included with the response.

     2.c.2 - Else if the glName is supported by the GLA, the GLA ensures
            a registered GLO signed the glAddOwner or glRemoveOwner
            request by checking that one of the names present in the
            digital signature certificate used to sign the glAddOwner
            or glDeleteOwner request matches the name of a registered
            GLO.

     2.c.2.a - If the names do not match, the GLA returns a response
               indicating cMCStatusInfoExt with cMCStatus.failed and
               otherInfo.extendedFailInfo.SKDFailInfo value of
               noGLONameMatch. Additionally, a signingTime attribute is
               included with the response.

     2.c.2.b - Else if the names match, the GLA returns a
               cMCStatusInfoExt.cMCStatus.success and a signingTime
               attribute (2 in Figure 4). The GLA also takes
               administrative actions to associate the new glOwnerName
               with the GL in the case of glAddOwner or to disassociate
               the old glOwnerName with the GL in the cased of
               glRemoveOwner.

     2.c.2.b.1 - The GLA applies confidentiality to the response by
               encapsulating the SignedData.PKIResponse in an
               EnvelopedData if the request was encapsulated in an
               EnvelopedData (see section 3.2.1.2).

     2.c.2.b.2 - The GLA can also optionally apply another SignedData
               over the EnvelopedData (see section 3.2.1.2).

     3 - Upon receipt of the cMCStatusInfoExt response, the GLO checks
        the signingTime and verifies the GLA's signature(s). If an


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        additional SignedData and/or EnvelopedData encapsulates the
        response (see section 3.2.1.2 or 3.2.2), the GLO verifies the
        outer signature and/or decrypt the outer layer prior to
        verifying the signature on the inner most SignedData.

     3.a - If the signingTime attribute value is not within the locally
           accepted time window, the GLO MAY return a response
           indicating cMCStatus.failed and otherInfo.failInfo.badTime
           and a signingTime attribute.

     3.b - Else if signature processing continues and if the signatures
           verify, the GLO checks that one of the names in the
           certificate used to sign the response matches the name of
           the GL.

     3.b.1 - If the name of GL does not match the name present in the
            certificate used to sign the message, the GLO should not
            believe the response.

     3.b.2 - Else if the name of the GL does match the name present in
            the certificate and:

     3.b.2.a - If the signatures verify and the response was
               cMCStatusInfoExt.cMCStatus.success, the GLO has
               successfully added or removed the GLO.

     3.b.2.b - Else if the signatures verify and the response was
               cMCStatusInfoExt.cMCStatus.failed with any reason, the
               GLO can reattempt to add or delete the GLO using the
               information provided in the response.

4.7. Indicate KEK Compromise

   There will be times when the shared KEK is compromised. GL members
   and GLOs use glkCompromise to tell the GLA that the shared KEK has
   been compromised. Figure 9 depicts the protocol interactions for GL
   Key Compromise. Note that error messages are not shown. Additionally,
   behavior for the optional transactionId, senderNonce, and
   recipientNonce CMC control attributes is not addressed in these
   procedures.









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                   +-----+  2{1}                  4  +----------+
                   | GLO | <----------+    +-------> | Member 1 |
                   +-----+  5,3{1}    |    |         +----------+
                   +-----+ <----------+    |      4  +----------+
                   | GLA |  1              +-------> |   ...    |
                   +-----+ <---------------+         +----------+
                                           |      4  +----------+
                                           +-------> | Member n |
                                                     +----------+

                      Figure 9 - GL Key Compromise

4.7.1. GL Member Initiated KEK Compromise Message

   The process for GL member initiated glkCompromise messages is as
   follows:

     1 - The GL member sends a
        SignedData.PKIData.controlSequence.glkCompromise request to the
        GLA (1 in Figure 9). The GL member includes the name of the GL
        in GeneralName. The GL member MUST also include the signingTime
        attribute with this request.

     1.a - The GL member can optionally apply confidentiality to the
           request by encapsulating the SignedData.PKIData in an
           EnvelopedData (see section 3.2.1.2). The glkCompromise can
           be included in an EnvelopedData generated with the
           compromised shared KEK.

     1.b - The GL member can also optionally apply another SignedData
           over the EnvelopedData (see section 3.2.1.2).

     2 - Upon receipt of the glkCompromise request, the GLA checks the
        signingTime and verifies the GL member signature(s). If an
        additional SignedData and/or EnvelopedData encapsulates the
        request (see section 3.2.1.2 or 3.2.2), the GLA verifies the
        outer signature and/or decrypt the outer layer prior to
        verifying the signature on the inner most SignedData.

     2.a - If the signingTime attribute value is not within the locally
           accepted time window, the GLA MAY return a response
           indicating cMCStatus.failed and otherInfo.failInfo.badTime
           and a signingTime attribute.

     2.b - Else if signature processing continues and if the signatures
           cannotbe verified, the GLA returns a cMCStatusInfoExt
           response indicating cMCStatus.failed and


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           otherInfo.failInfo.badMessageCheck. Additionally, a
           signingTime attribute is included with the response.

     2.c - Else if the signatures verify, the GLA makes sure the GL is
           supported by checking that the indicated GL name matches a
           glName stored on the GLA.

     2.c.1 - If the glName is not supported by the GLA, the GLA returns
            a response indicating cMCStatusInfoExt with
            cMCStatus.failed and otherInfo.extendedFailInfo.SKDFailInfo
            value of invalidGLName. Additionally, a signingTime
            attribute is included with the response.

     2.c.2 - Else if the glName is supported by the GLA, the GLA checks
            who signed the request. For GLOs, one of the names in the
            certificate used to sign the request needs to match a
            registered GLO. For the member, the name in
            glMember.glMemberName needs to match one of the names in
            the certificate used to sign the request.

     2.c.2.a - If the GLO signed the request, the GLA generates a glKey
               message as described in section 5 to rekey the GL (4 in
               Figure 9).

     2.c.2.b - Else if someone other than the GLO signed the request,
               the GLA forwards the glkCompromise message (see section
               3.2.3) to the GLO (2{1} in Figure 9). If there is more
               than one GLO, to which GLO the request is forwarded is
               beyond the scope of this document. Further processing by
               the GLO is discussed in section 4.7.2.

4.7.2. GLO Initiated KEK Compromise Message

   The process for GLO initiated glkCompromise messages is as follows:

     1 - The GLO either:

     1.a - Generates the glkCompromise message itself by sending a
           SignedData.PKIData.controlSequence.glkCompromise request to
           the GLA (5 in Figure 9). The GLO includes the name of the GL
           in GeneralName. The GLO MUST also include a signingTime
           attribute with this request.

     1.a.1 - The GLO can optionally apply confidentiality to the request
            by encapsulating the SignedData.PKIData in an EnvelopedData
            (see section 3.2.1.2). The glkCompromise can be included in
            an EnvelopedData generated with the compromised shared KEK.


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     1.a.2 - The GLO can also optionally apply another SignedData over
            the EnvelopedData (see section 3.2.1.2).

     1.b - Otherwise, checks the signingTime and verifies the GLA and GL
           member signatures on the forwarded glkCompromise message. If
           an additional SignedData and/or EnvelopedData encapsulates
           the request (see section 3.2.1.2 or 3.2.2), the GLO verifies
           the outer signature and/or decrypt the outer layer prior to
           verifying the signature on the inner most SignedData.

     1.b.1 - If the signingTime attribute value is not within the
            locally accepted time window, the GLO MAY return a response
            indicating cMCStatus.failed and otherInfo.failInfo.badTime
            and a signingTime attribute.

     1.b.2 - Else if signature processing continues and if the
            signatures cannot be verified, the GLO returns a
            cMCStatusInfoExt response indicating cMCStatus.failed and
            otherInfo.failInfo.badMessageCheck. Additionally, a
            signingTime attribute is included with the response.

     1.b.2.a - If the signatures verify, the GLO checks the names in the
               certificate match the name of the signer (i.e., the name
               in the certificate used to sign the GL member's request
               is the GL member).

     1.b.2.a.1 - If either name does not match, the GLO ought not trust
                 the signer and it ought not forward the message to the
                 GLA.

     1.b.2.a.2 - Else if the names match and the signatures verify, the
                 GLO determines whether to forward the glkCompromise
                 message back to the GLA (3{1} in Figure 9). Further
                 processing by the GLA is in 2 of section 4.7.1. The
                 GLO can also return a response to the prospective
                 member with cMCStatusInfoExt.cMCtatus.success
                 indicating that the glkCompromise message was
                 successfully received.

4.8. Request KEK Refresh

   There will be times when GL members have unrecoverably lost their
   shared KEK. The shared KEK is not compromised and a rekey of the
   entire GL is not necessary. GL members use the glkRefresh message to
   request that the shared KEK(s) be redistributed to them. Figure 10
   depicts the protocol interactions for GL Key Refresh. Note that error
   messages are not shown. Additionally, behavior for the optional


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   transactionId, senderNonce, and recipientNonce CMC control attributes
   is not addressed in these procedures.

                         +-----+   1       2   +----------+
                         | GLA | <-----------> |  Member  |
                         +-----+               +----------+

                            Figure 10 - GL KEK Refresh

   The process for glkRefresh is as follows:

     1 - The GL member sends a
        SignedData.PKIData.controlSequence.glkRefresh request to the
        GLA (1 in Figure 10). The GL member includes name of the GL in
        GeneralName. The GL member MUST also include a signingTime
        attribute with this request.

     1.a - The GL member can optionally apply confidentiality to the
           request by encapsulating the SignedData.PKIData in an
           EnvelopedData (see section 3.2.1.2).

     1.b - The GL member can also optionally apply another SignedData
           over the EnvelopedData (see section 3.2.1.2).

     2 - Upon receipt of the glkRefresh request, the GLA checks the
        signingTime and verifies the GL member signature(s). If an
        additional SignedData and/or EnvelopedData encapsulates the
        request (see section 3.2.1.2 or 3.2.2), the GLA verifies the
        outer signature and/or decrypt the outer layer prior to
        verifying the signature on the inner most SignedData.

     2.a - If the signingTime attribute value is not within the locally
           accepted time window, the GLA MAY return a response
           indicating cMCStatus.failed and otherInfo.failInfo.badTime
           and a signingTime attribute.

     2.b - Else if signature processing continues and if the signatures
           cannot be verified, the GLA returns a cMCStatusInfoExt
           response indicating cMCStatus.failed and
           otherInfo.failInfo.badMessageCheck. Additionally, a
           signingTime attribute is included with the response.

     2.c - Else if the signatures verify, the GLA makes sure the GL is
           supported by checking that the GLGeneralName matches a
           glName stored on the GLA.




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     2.c.1 - If the name of the GL is not supported by the GLA, the GLA
            returns a response indicating cMCStatusInfoExt with
            cMCStatus.failed and otherInfo.extendedFailInfo.SKDFailInfo
            value of invalidGLName. Additionally, a signingTime
            attribute is included with the response.

     2.c.2 - Else if the glName is supported by the GLA, the GLA ensures
            the GL member is on the GL.

     2.c.2.a - If the glMemberName is not present on the GL, the GLA
               returns a response indicating cMCStatusInfoExt with
               cMCStatus.failed and
               otherInfo.extendedFailInfo.SKDFailInfo value of noSpam.
               Additionally, a signingTime attribute is included with
               the response.

     2.c.2.b - Else if the glMemberName is present on the GL, the GLA
               returns a cMCStatusInfoExt.cMCStatus.success, a
               signingTime attribute, and a glKey message (2 in Figure
               10) as described in section 5.

4.9. GLA Query Request and Response

   There will be certain times when a GLO is having trouble setting up a
   GL because they do not know the algorithm(s) or some other
   characteristic that the GLA supports. There can also be times when
   prospective GL members or GL members need to know something about the
   GLA (these requests are not defined in the document). The
   glaQueryRequest and glaQueryResponse message have been defined to
   support determining this information. Figure 11 depicts the protocol
   interactions for glaQueryRequest and glaQueryResponse. Note error
   messages are not shown. Additionally, behavior for the optional
   transactionId, senderNonce, and recipientNonce CMC control attributes
   is not addressed in these procedures.

                         +-----+   1    2  +------------------+
                         | GLA | <-------> | GLO or GL Member |
                         +-----+           +------------------+

                   Figure 11 - GLA Query Request & Response

   The process for glaQueryRequest and glaQueryResponse is as follows:

     1 - The GLO, GL member, or prospective GL member sends a
        SignedData.PKIData.controlSequence.glaQueryRequest request to
        the GLA (1 in Figure 11). The GLO, GL member, or prospective GL
        member indicates the information they are interested in


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        receiving from the GLA. Additionally, a signingTime attribute
        is included with this request.

     1.a - The GLO, GL member, or prospective GL member can optionally
           apply confidentiality to the request by encapsulating the
           SignedData.PKIData in an EnvelopedData (see section
           3.2.1.2).

     1.b - The GLO, GL member, or prospective GL member can also
           optionally apply another SignedData over the EnvelopedData
           (see section 3.2.1.2).

     2 - Upon receipt of the glaQueryRequest, the GLA determines if it
        accepts glaQueryRequest messages.

     2.a - If the GLA does not accept glaQueryRequest messages, the GLA
           returns a cMCStatusInfoExt response indicating
           cMCStatus.noSupport and any other information in
           statusString.

     2.b - Else if the GLA does accept GLAQueryRequests, the GLA checks
           the signingTime and verifies the GLO, GL member, or
           prospective GL member signature(s). If an additional
           SignedData and/or EnvelopedData encapsulates the request
           (see section 3.2.1.2 or 3.2.2), the GLA verifies the outer
           signature and/or decrypt the outer layer prior to verifying
           the signature on the inner most SignedData.

     2.b.1 - If the signingTime attribute value is not within the
            locally accepted time window, the GLA MAY return a response
            indicating cMCStatus.failed and otherInfo.failInfo.badTime
            and a signingTime attribute.

     2.b.2 - Else if the signature processing continues and if the
            signatures cannot be verified, the GLA returns a
            cMCStatusInfoExt response indicating cMCStatus.failed and
            otherInfo.failInfo.badMessageCheck. Additionally, a
            signingTime attribute is included with the response.

     2.b.3 - Else if the signatures verify, the GLA returns a
            glaQueryResponse (2 in Figure 11) with the correct response
            if the glaRequestType is supported or return a
            cMCStatusInfoExt response indicating cMCStatus.noSupport if
            the glaRequestType is not supported. Additionally, a
            signingTime attribute is included with the response.




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     2.b.3.a - The GLA applies confidentiality to the response by
               encapsulating the SignedData.PKIResponse in an
               EnvelopedData if the request was encapsulated in an
               EnvelopedData (see section 3.2.1.2).

     2.b.3.b - The GLA can also optionally apply another SignedData over
               the EnvelopedData (see section 3.2.1.2).

     3 - Upon receipt of the glaQueryResponse, the GLO, GL member, or
        prospective GL member checks the signingTime and verifies the
        GLA signature(s). If an additional SignedData and/or
        EnvelopedData encapsulates the response (see section 3.2.1.2 or
        3.2.2), the GLO, GL member, or prospective GL member verifies
        the outer signature and/or decrypt the outer layer prior to
        verifying the signature on the inner most SignedData.

     3.a - If the signingTime attribute value is not within the locally
           accepted time window, the GLO, GL member, or prospective GL
           member MAY return a response indicating cMCStatus.failed and
           otherInfo.failInfo.badTime and a signingTime attribute.

     3.b - Else if signature processing continues and if the signatures
           do not verify, the GLO, GL member, or prospective GL member
           returns a cMCStatusInfoExt response indicating
           cMCStatus.failed and otherInfo.failInfo.badMessageCheck.
           Additionally, a signingTime attribute is included with the
           response.

     3.c - Else if the signatures verify, then the GLO, GL member, or
           prospective GL member checks that one of the names in the
           certificate used to sign the response matches the name of
           the GL.

     3.c.1 - If the name of the GL does not match the name present in
            the certificate used to sign the message, the GLO ought not
            believe the response.

     3.c.2 - Else if the name of the GL matches the name present in the
            certificate and the response was glaQueryResponse, then the
            GLO, GL member, or prospective GL member may use the
            information contained therein.

4.10. Update Member Certificate

   When the GLO generates a glAddMember request, when the GLA generates
   a glKey message, or when the GLA processes a glAddMember there can be
   instances when GL member's certificate has expired or is invalid. In


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   these instances the GLO or GLA may request that the GL member provide
   a new certificate to avoid the GLA from being unable to generate a
   glKey message for the GL member. There might also be times when the
   GL member knows their certificate is about to expire or has been
   revoked and they will not be able to receive GL rekeys. Behavior for
   the optional transactionId, senderNonce, and recipientNonce CMC
   control attributes is not addressed in these procedures.

4.10.1. GLO and GLA Initiated Update Member Certificate

   The process for GLO initiated glUpdateCert is as follows:

     1 - The GLO or GLA sends a
        SignedData.PKIData.controlSequence.glProvideCert request to the
        GL member. The GLO or GLA indicates the GL name in glName and
        the GL member name in glMemberName. Additionally, a signingTime
        attribute is included with this request.

     1.a - The GLO or GLA can optionally apply confidentiality to the
           request by encapsulating the SignedData.PKIData in an
           EnvelopedData (see section 3.2.1.2). If the GL member's PKC
           has been revoked, the GLO or GLA ought not use it to
           generate the EnvelopedData that encapsulates the
           glProvideCert request.

     1.b - The GLO or GLA can also optionally apply another SignedData
           over the EnvelopedData (see section 3.2.1.2).

     2 - Upon receipt of the glProvideCert message, the GL member checks
        the signingTime and verifies the GLO or GLA signature(s). If an
        additional SignedData and/or EnvelopedData encapsulates the
        response (see section 3.2.1.2 or 3.2.2), the GL member verifies
        the outer signature and/or decrypt the outer layer prior to
        verifying the signature on the inner most SignedData.

     2.a - If the signingTime attribute value is not within the locally
           accepted time window, the GL member MAY return a response
           indicating cMCStatus.failed and otherInfo.failInfo.badTime
           and a signingTime attribute.

     2.b - Else if signature processing continues and if the signatures
           cannot be verified, the GL member returns a cMCStatusInfoExt
           response indicating cMCStatus.failed and
           otherInfo.failInfo.badMessageCheck. Additionally, a
           signingTime attribute is included with the response.




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     2.c - Else if the signatures verify, the GL member generates a
           Signed.PKIResponse.controlSequence.glUpdateCert that
           includes the GL name in glName, the member name in
           glMember.glMemberName, their encryption certificate in
           glMember.certificates.pKC. The GL member can also include
           any attribute certificates associated with their encryption
           certificate in glMember.certificates.aC, and the
           certification path associated with their encryption and
           attribute certificates in glMember.certificates.certPath.
           Additionally, a signingTime attribute is included with the
           response.

     2.c.1 - The GL member can optionally apply confidentiality to the
            request by encapsulating the SignedData.PKIResponse in an
            EnvelopedData (see section 3.2.1.2). If the GL member's PKC
            has been revoked, the GL member ought not use it to
            generate the EnvelopedData that encapsulates the
            glProvideCert request.

     2.c.2 - The GL member can also optionally apply another SignedData
            over the EnvelopedData (see section 3.2.1.2).

     3 - Upon receipt of the glUpdateCert message, the GLO or GLA checks
        the signingTime and verifies the GL member signature(s). If an
        additional SignedData and/or EnvelopedData encapsulates the
        response (see section 3.2.1.2 or 3.2.2), the GL member verifies
        the outer signature and/or decrypt the outer layer prior to
        verifying the signature on the inner most SignedData.

     3.a - If the signingTime attribute value is not within the locally
           accepted time window, the GLO or GLA MAY return a response
           indicating cMCStatus.failed and otherInfo.failInfo.badTime
           and a signingTime attribute.

     3.b - Else if signature processing continues and if the signatures
           cannot be verified, the GLO or GLA returns a
           cMCStatusInfoExt response indicating cMCStatus.failed and
           otherInfo.failInfo.badMessageCheck. Additionally, a
           signingTime attribute is included with the response.

     3.c - Else if the signatures verify, the GLO or GLA verifies the
           member's encryption certificate.

     3.c.1 - If the member's encryption certificate cannot be verified,
            the GLO returns either another glProvideCert request or a
            cMCStatusInfoExt with cMCStatus.failed and the reason why
            in cMCStatus.statusString. glProvideCert should be returned


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            only a certain number of times because if the GL member
            does not have a valid certificate they will never be able
            to return one. Additionally, a signingTime attribute is
            included with either response.

     3.c.2 - Else if the member's encryption certificate cannot be
            verified, the GLA returns another glProvideCert request to
            the GL member or a cMCStatusInfoExt with cMCStatus.failed
            and the reason why in cMCStatus.statusString to the GLO.
            glProvideCert should be returned only a certain number of
            times because if the GL member does not have a valid
            certificate they will never be able to return one.
            Additionally, a signingTime attribute is included with the
            response.

     3.c.3 - Else if the member's encryption certificate verifies, the
            GLO or GLA will use it in subsequent glAddMember requests
            and glKey messages associated with the GL member.

4.10.2. GL Member Initiated Update Member Certificate

   The process for an unsolicited GL member glUpdateCert is as follows:

     1 - The GL member sends a
        Signed.PKIData.controlSequence.glUpdateCert that includes the
        GL name in glName, the member name in glMember.glMemberName,
        their encryption certificate in glMember.certificates.pKC. The
        GL member can also include any attribute certificates
        associated with their encryption certificate in
        glMember.certificates.aC, and the certification path associated
        with their encryption and attribute certificates in
        glMember.certificates.certPath. The GL member MUST also include
        a signingTime attribute with this request.

     1.a - The GL member can optionally apply confidentiality to the
           request by encapsulating the SignedData.PKIData in an
           EnvelopedData (see section 3.2.1.2). If the GL member's PKC
           has been revoked, the GLO or GLA ought not use it to
           generate the EnvelopedData that encapsulates the
           glProvideCert request.

     1.b - The GL member can also optionally apply another SignedData
           over the EnvelopedData (see section 3.2.1.2).

     2 - Upon receipt of the glUpdateCert message, the GLA checks the
        signingTime and verifies the GL member signature(s). If an
        additional SignedData and/or EnvelopedData encapsulates the


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        response (see section 3.2.1.2 or 3.2.2), the GLA verifies the
        outer signature and/or decrypt the outer layer prior to
        verifying the signature on the inner most SignedData.

     2.a - If the signingTime attribute value is not within the locally
           accepted time window, the GLA MAY return a response
           indicating cMCStatus.failed and otherInfo.failInfo.badTime
           and a signingTime attribute.

     2.b - Else if signature processing continues and if the signatures
           cannot be verified, the GLA returns a cMCStatusInfoExt
           response indicating cMCStatus.failed and
           otherInfo.failInfo.badMessageCheck.

     2.c - Else if the signatures verify, the GLA verifies the member's
           encryption certificate.

     2.c.1 - If the member's encryption certificate cannot be verified,
            the GLA returns another glProvideCert request to the GL
            member or a cMCStatusInfoExt with cMCStatus.failed and the
            reason why in cMCStatus.statusString to the GLO.
            glProvideCert ought not be returned indefinitely;  if the
            GL member does not have a valid certificate they will never
            be able to return one. Additionally, a signingTime
            attribute is included with the response.

     2.c.2 - Else if the member's encryption certificate verifies, the
            GLA will use it in subsequent glAddMember requests and
            glKey messages associated with the GL member. The GLA also
            forwards the glUpdateCert message to the GLO.

5. Distribution Message

   The GLA uses the glKey message to distribute new, shared KEK(s) after
   receiving glAddMember, glDeleteMember (for closed and managed GLs),
   glRekey, glkCompromise, or glkRefresh requests and returning a
   cMCStatusInfoExt response for the respective request. Figure 12
   depicts the protocol interactions to send out glKey messages. Unlike
   the procedures defined for the administrative messages, the
   procedures defined in this section MUST be implemented by GLAs for
   origination and by GL members on reception. Note that error messages
   are not shown. Additionally, behavior for the optional transactionId,
   senderNonce, and recipientNonce CMC control attributes is not
   addressed in these procedures.





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                                        1   +----------+
                                  +-------> | Member 1 |
                                  |         +----------+
                      +-----+     |     1   +----------+
                      | GLA | ----+-------> |   ...    |
                      +-----+     |         +----------+
                                  |     1   +----------+
                                  +-------> | Member n |
                                            +----------+

                      Figure 12 - GL Key Distribution

   If the GL was setup with GLKeyAttributes.recipientsNotMutuallyAware
   set to TRUE, a separate glKey message MUST be sent to each GL member
   so as to not divulge information about the other GL members.

   When the glKey message is generated as a result of a:

     - glAddMember request,

     - glkComrpomise indication,

     - glkRefresh request,

     - glDeleteMember request with the GL's glAdministration set to
       managed or closed, and

     - glRekey request with generationCounter set to zero (0).

   The GLA MUST use either the kari (see section 12.3.2 of [CMS]) or
   ktri (see section 12.3.1 of [CMS]) choice in
   glKey.glkWrapped.RecipientInfo to ensure only the intended recipients
   receive the shared KEK. The GLA MUST support the ktri choice.

   When the glKey message is generated as a result of a glRekey request
   with generationCounter greater than zero (0) or when the GLA controls
   rekeys, the GLA MAY use the kari, ktri, or kekri (see section 12.3.3
   of [CMS]) in glKey.glkWrapped.RecipientInfo to ensure only the
   intended recipients receive the shared KEK. The GLA MUST support the
   RecipientInfo.ktri choice.

5.1. Distribution Process

   When a glKey message is generated the process is as follows:

     1 - The GLA MUST send a SignedData.PKIData.controlSequence.glKey to
        each member by including: glName, glIdentifier, glkWrapped,


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        glkAlgorithm, glkNotBefore, and glkNotAfter. If the GLA can not
        generate a glKey message for the GL member because the GL
        member's PKC has expired or is otherwise invalid, the GLA MAY
        send a glUpdateCert to the GL member requesting a new
        certificate be provided (see section 4.10). The number of glKey
        messages generated for the GL is described in section 3.1.16.
        Additionally, a signingTime attribute is included with the
        distribution message(s).

     1.a - The GLA MAY optionally apply another confidentiality layer to
           the message by encapsulating the SignedData.PKIData in
           another EnvelopedData (see section 3.2.1.2).

     1.b - The GLA MAY also optionally apply another SignedData over the
           EnvelopedData.SignedData.PKIData (see section 3.2.1.2).

     2 - Upon receipt of the glKey message, the GL members MUST check
        the signingTime and verify the signature over the inner most
        SignedData.PKIData. If an additional SignedData and/or
        EnvelopedData encapsulates the message (see section 3.2.1.2 or
        3.2.2), the GL Member MUST verify the outer signature and/or
        decrypt the outer layer prior to verifying the signature on the
        SignedData.PKIData.controlSequence.glKey.

     2.a - If the signingTime attribute value is not within the locally
           accepted time window, the GLA MAY return a response
           indicating cMCStatus.failed and otherInfo.failInfo.badTime
           and a signingTime attribute.

     2.b - Else if signature processing continues and if the signatures
           cannot be verified, the GL member MUST return a
           cMCStatusInfoExt response indicating cMCStatus.failed and
           otherInfo.failInfo.badMessageCheck. Additionally, a
           signingTime attribute is included with the response.

     2.c - Else if the signatures verify, the GL member process the
           RecipientInfos according to [CMS]. Once unwrapped the GL
           member should store the shared KEK in a safe place. When
           stored, the glName, glIdentifier, and shared KEK should be
           associated.  Additionally, the GL member MUST return a
           cMCStatusInfoExt indicating cMCStatus.success to tell the
           GLA the KEK was received.







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6. Algorithms

   This section lists the algorithms that MUST be implemented.
   Additional algorithms that SHOULD be implemented are also included.
   Further algorithms MAY also be implemented.

6.1. KEK Generation Algorithm

   Implementations MUST randomly generate content-encryption keys,
   message-authentication keys, initialization vectors (IVs), and
   padding. Also, the generation of public/private key pairs relies on a
   random numbers. The use of inadequate pseudo-random number generators
   (PRNGs) to generate cryptographic keys can result in little or no
   security. An attacker may find it much easier to reproduce the PRNG
   environment that produced the keys, searching the resulting small set
   of possibilities, rather than brute force searching the whole key
   space.  The generation of quality random numbers is difficult.  RFC
   1750 [RANDOM] offers important guidance in this area, and Appendix 3
   of FIPS Pub 186 [FIPS] provides one quality PRNG technique.

6.2. Shared KEK Wrap Algorithm

   In the mechanisms described in sections 5, the shared KEK being
   distributed in glkWrapped MUST be protected by a key of equal or
   greater length (i.e., if an AES 128-bit key is being distributed a
   key of 128-bits or greater must be used to protect the key). The
   algorithm object identifiers included in glkWrapped are as specified
   in [CMSALG] and [CMSAES].

6.3. Shared KEK Algorithm

   The shared KEK distributed and indicated in glkAlgorithm MUST support
   the symmetric key-encryption algorithms as specified in section
   [CMSALG] and [CMSAES].

7. Message Transport

   SMTP [SMTP] MUST be supported. Other transport mechanisms MAY also be
   supported.

8. Security Considerations

   As GLOs control setting up and tearing down the GL, rekeying the GL,
   and can control member additions and deletions, GLOs play an
   important role in the management of the GL, and only "trusted" GLOs
   should be used.



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   If a member is deleted or removed from a closed or a managed GL, the
   GL needs to be rekeyed. If the GL is not rekeyed after a member is
   removed or deleted, the member still posses the group key and will be
   able to continue to decrypt any messages that can be obtained.

   Members who store KEKs MUST associate the name of the GLA that
   distributed the key so that the members can make sure subsequent
   rekeys are originated from the same entity.

   When generating keys, care should be taken to ensure that the key
   size is not too small and duration too long because attackers will
   have more time to attack the key. Key size should be selected to
   adequately protect sensitive business communications.

   GLOs and GLAs need to make sure that the generationCounter and
   duration are not too large. For example, if the GLO indicates that
   the generationCounter is 14 and the duration is one year, then 14
   keys are generated each with a validity period of a year. An attacker
   will have at least 13 years to attack the final key.

   Assume that two or more parties have a shared KEK, and the shared KEK
   is used to encrypt a second KEK for confidential distribution to
   those parties.  The second KEK might be used to encrypt a third KEK;
   the third KEK might be used to encrypt a fourth KEK; and so on.  If
   any of the KEKs in such a chain is compromised, all of the subsequent
   KEKs in the chain MUST also be considered compromised.

   An attacker can attack the group's shared KEK by attacking one
   member's copy of the shared KEK or attacking multiple member's copies
   of the shared KEK. For the attacker it may be easier to either attack
   the group member with the weakest security protecting their copy of
   the shared KEK or by attacking multiple group members.

   An aggregation of the information gathered during the attack(s) may
   lead to the compromise of the group's shared KEK.  Mechanisms to
   protect the shared KEK should be commensurate with value of the data
   being protected.

   The nonce and signingTime attributes are used to protect against
   replay attacks. However, these provisions are only helpful if
   entities maintain state information about the messages they have sent
   or received for comparison. If sufficient information is not
   maintained on each exchange, nonces and signingTime are not helpful.

   Local policy determines the amount and duration of state information
   that is maintained. Additionally, without a unified time source,
   there is the possibility of clocks drifting. Local policy determines


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   the acceptable difference between the local time and signingTime,
   which must compensate for unsynchronized clock. Implementations MUST
   handle messages with siginingTime attributes that indicate they were
   created in the future.

9. IANA Considerations

   None: All identifiers are already registered.  Please remove this
   section prior to publication as an RFC.

10. Acknowledgements

   Thanks to Russ Housley and Jim Schaad for providing much of the
   background and review required to write this document.

11. References

11.1. Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
               Requirement Levels", BCP 14, RFC 2119, March 1997.

   [CMS]       Housley, R., "Cryptographic Message Syntax," RFC 3852,
               July 2004.

   [CMC]       Myers, M., Liu, X., Schaad, J., Weinsten, J.,
               "Certificate Management Message over CMS," work-in-
               progress, December 2007.

   [PROFILE]   Housley, R., Ford, W., Polk, W. and D. Solo, "Internet
               X.509 Public Key Infrastructure: Certificate and CRL
               Profile", RFC 3280, April 2002.

   [ACPROF]    Farrell, S., Housley, R., "An Internet Attribute
               Certificate Profile for Authorization", RFC 3281, April
               2002.

   [MSG]       Ramsdale, B., "S/MIME Version 3.1 Message Specification,"
               RFC 3851, July 2004.

   [ESS]       Hoffman, P., "Extended Security Services for S/MIME", RFC
               2634, June 1999.

               Schaad, J., "Extended Security Services (ESS) Update:
               Adding CertID Algorithm Agility", RFC 5035, August 2007.




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   [CMSALG]   Housley, R., "Cryptographic Message Syntax (CMS)
               Algorithms", RFC 3370, August 2002.

   [CMSAES]   Schaad, J., "Advanced Encryption Standard (AES) Encryption
               Algorithm in Cryptographic Message Syntax (CMS) ", RFC
               3565, July 2003.

   [SMTP]      Klensin, J., "Simple Mail Transport Protocol," RFC 2821,
               April 2001.

11.2. Informative References

   [X400TRANS] Hoffman, P., and C. Bonatti, "Transporting S/MIME Objects
               in X.400", RFC 3855, July 2004.

   [RANDOM]    Eastlake, D., Crocker, S. and J. Schiller, "Randomness
               Recommendations for Security", RFC 4086, June 2005.

   [FIPS]      National Institute of Standards and Technology. FIPS Pub
               186-2: Digital Signature Standard.  27 January 2000.

12. ASN.1 Module

   SMIMESymmetricKeyDistribution

   { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs-9(9)
     smime(16) modules(0) symkeydist(12) }

   DEFINITIONS IMPLICIT TAGS ::=

   BEGIN

   -- EXPORTS All --
   -- The types and values defined in this module are exported for use
   -- in the other ASN.1 modules.  Other applications may use them for
   -- their own purposes.

   IMPORTS

   -- PKIX Part 1 - Implicit

   GeneralName

     FROM PKIX1Implicit88 { iso(1) identified-organization(3) dod(6)
       internet(1) security(5) mechanisms(5) pkix(7) id-mod(0)
       id-pkix1-implicit(19) }



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   -- PKIX Part 1 - Explicit

   AlgorithmIdentifier, Certificate

     FROM PKIX1Explicit88 { iso(1) identified-organization(3) dod(6)
       internet(1) security(5) mechanisms(5) pkix(7) id-mod(0)
       id-pkix1-explicit(18) }

   -- Cryptographic Message Syntax

   RecipientInfos, KEKIdentifier, CertificateSet

     FROM CryptographicMessageSyntax2004 {iso(1) member-body(2) us(840)
       rsadsi(113549) pkcs(1) pkcs-9(9) smime(16) modules(0)
       cms-2004(24) }

   -- Advanced Encryption Standard (AES) with CMS

   id-aes128-wrap

     FROM CMSAesRsaesOaep { iso(1) member-body(2) us(840) rsadsi(113549)
       pkcs(1) pkcs-9(9) smime(16) modules(0) id-mod-cms-aes(19) }

   -- Attribute Certificate Profile

   AttributeCertificate

     FROM PKIXAttributeCertificate { iso(1) identified-organization(3)
       dod(6) internet(1) security(5) mechanisms(5) pkix(7) id-mod(0)
       id-mod-attribute-cert(12) };

   -- This defines the GL symmetric key distribution object identifier
   -- arc.

   id-skd OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840)
     rsadsi(113549) pkcs(1) pkcs-9(9) smime(16) skd(8) }

   -- This defines the GL Use KEK control attribute

   id-skd-glUseKEK OBJECT IDENTIFIER ::= { id-skd 1}

   GLUseKEK ::= SEQUENCE {
     glInfo            GLInfo,
     glOwnerInfo       SEQUENCE SIZE (1..MAX) OF GLOwnerInfo,
     glAdministration  GLAdministration DEFAULT 1,
     glKeyAttributes   GLKeyAttributes OPTIONAL }



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   GLInfo ::= SEQUENCE {
     glName     GeneralName,
     glAddress  GeneralName }


   GLOwnerInfo ::= SEQUENCE {
     glOwnerName     GeneralName,
     glOwnerAddress  GeneralName,
     certificates    Certificates OPTIONAL }

   GLAdministration ::= INTEGER {
     unmanaged  (0),
     managed    (1),
     closed     (2) }

   GLKeyAttributes ::= SEQUENCE {
     rekeyControlledByGLO       [0] BOOLEAN DEFAULT FALSE,
     recipientsNotMutuallyAware [1] BOOLEAN DEFAULT TRUE,
     duration                   [2] INTEGER DEFAULT 0,
     generationCounter          [3] INTEGER DEFAULT 2,
     requestedAlgorithm         [4] AlgorithmIdentifier
                                      DEFAULT { id-aes128-wrap } }

   -- This defines the Delete GL control attribute.
   -- It has the simple type GeneralName.

   id-skd-glDelete OBJECT IDENTIFIER ::= { id-skd 2}

   DeleteGL ::= GeneralName

   -- This defines the Add GL Member control attribute

   id-skd-glAddMember OBJECT IDENTIFIER ::= { id-skd 3}

   GLAddMember ::= SEQUENCE {
     glName    GeneralName,
     glMember  GLMember }

     GLMember ::= SEQUENCE {
     glMemberName     GeneralName,
     glMemberAddress  GeneralName OPTIONAL,
     certificates     Certificates OPTIONAL }







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   Certificates ::= SEQUENCE {
     pKC       [0] Certificate OPTIONAL,
                   -- See [PROFILE]
     aC        [1] SEQUENCE SIZE (1.. MAX) OF
                     AttributeCertificate OPTIONAL,
                   -- See [ACPROF]
     certPath  [2] CertificateSet OPTIONAL }
                   -- From [CMS]

   -- This defines the Delete GL Member control attribute

   id-skd-glDeleteMember OBJECT IDENTIFIER ::= { id-skd 4}

   GLDeleteMember ::= SEQUENCE {
     glName            GeneralName,
     glMemberToDelete  GeneralName }

   -- This defines the Delete GL Member control attribute

   id-skd-glRekey OBJECT IDENTIFIER ::= { id-skd 5}

   GLRekey ::= SEQUENCE {
     glName              GeneralName,
     glAdministration    GLAdministration OPTIONAL,
     glNewKeyAttributes  GLNewKeyAttributes OPTIONAL,
     glRekeyAllGLKeys    BOOLEAN OPTIONAL }

   GLNewKeyAttributes ::= SEQUENCE {
     rekeyControlledByGLO       [0] BOOLEAN OPTIONAL,
     recipientsNotMutuallyAware [1] BOOLEAN OPTIONAL,
     duration                   [2] INTEGER OPTIONAL,
     generationCounter          [3] INTEGER OPTIONAL,
     requestedAlgorithm         [4] AlgorithmIdentifier OPTIONAL }

   -- This defines the Add and Delete GL Owner control attributes

   id-skd-glAddOwner OBJECT IDENTIFIER ::= { id-skd 6}

   id-skd-glRemoveOwner OBJECT IDENTIFIER ::= { id-skd 7}

   GLOwnerAdministration ::= SEQUENCE {
     glName       GeneralName,
     glOwnerInfo  GLOwnerInfo }

   -- This defines the GL Key Compromise control attribute.
   -- It has the simple type GeneralName.



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   id-skd-glKeyCompromise OBJECT IDENTIFIER ::= { id-skd 8}

   GLKCompromise ::= GeneralName

   -- This defines the GL Key Refresh control attribute.

   id-skd-glkRefresh OBJECT IDENTIFIER ::= { id-skd 9}

   GLKRefresh ::= SEQUENCE {
     glName  GeneralName,
     dates   SEQUENCE SIZE (1..MAX) OF Date }

   Date ::= SEQUENCE {
     start GeneralizedTime,
     end   GeneralizedTime OPTIONAL }

   -- This defines the GLA Query Request control attribute.

   id-skd-glaQueryRequest OBJECT IDENTIFIER ::= { id-skd 11}

   GLAQueryRequest ::= SEQUENCE {
     glaRequestType   OBJECT IDENTIFIER,
     glaRequestValue  ANY DEFINED BY glaRequestType }

   -- This defines the GLA Query Response control attribute.

   id-skd-glaQueryResponse OBJECT IDENTIFIER ::= { id-skd 12}

   GLAQueryResponse ::= SEQUENCE {
     glaResponseType   OBJECT IDENTIFIER,
     glaResponseValue  ANY DEFINED BY glaResponseType }

   -- This defines the GLA Request/Response (glaRR) arc for
   -- glaRequestType/glaResponseType.

   id-cmc-glaRR OBJECT IDENTIFIER ::= {
     iso(1) identified-organization(3) dod(6) internet(1) security(5)
     mechanisms(5) pkix(7) cmc(7) glaRR(99) }

   -- This defines the Algorithm Request

   id-cmc-gla-skdAlgRequest OBJECT IDENTIFIER ::= { id-cmc-glaRR 1 }

   SKDAlgRequest ::= NULL

   -- This defines the Algorithm Response



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   id-cmc-gla-skdAlgResponse OBJECT IDENTIFIER ::= { id-cmc-glaRR 2 }

   -- Note that the response for algorithmSupported request is the
   -- smimeCapabilities attribute as defined in MsgSpec [MSG].
   -- This defines the control attribute to request an updated
   -- certificate to the GLA.

   id-skd-glProvideCert OBJECT IDENTIFIER ::= { id-skd 13}

   GLManageCert ::= SEQUENCE {
     glName    GeneralName,
     glMember  GLMember }

   -- This defines the control attribute to return an updated
   -- certificate to the GLA. It has the type GLManageCert.

   id-skd-glManageCert OBJECT IDENTIFIER ::= { id-skd 14}

   -- This defines the control attribute to distribute the GL shared
   -- KEK.

   id-skd-glKey OBJECT IDENTIFIER ::= { id-skd 15}

   GLKey ::= SEQUENCE {
     glName        GeneralName,
     glIdentifier  KEKIdentifier,   -- See [CMS]
     glkWrapped    RecipientInfos,  -- See [CMS]
     glkAlgorithm  AlgorithmIdentifier,
     glkNotBefore  GeneralizedTime,
     glkNotAfter   GeneralizedTime }

   -- This defines the CMC error types

   id-cet-skdFailInfo  OBJECT IDENTIFIER ::= {
     iso(1) identified-organization(3) dod(6) internet(1) security(5)
     mechanisms(5) pkix(7) cet(15) skdFailInfo(1) }













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   SKDFailInfo ::= INTEGER {
     unspecified           (0),
     closedGL              (1),
     unsupportedDuration   (2),
     noGLACertificate      (3),
     invalidCert           (4),
     unsupportedAlgorithm  (5),
     noGLONameMatch        (6),
     invalidGLName         (7),
     nameAlreadyInUse      (8),
     noSpam                (9),
     deniedAccess          (10),
     alreadyAMember        (11),
     notAMember            (12),
     alreadyAnOwner        (13),
      notAnOwner            (14) }

   END -- SMIMESymmetricKeyDistribution































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Author's Addresses

   Sean Turner

   IECA, Inc.
   3057 Nutley Street, Suite 106
   Fairfax, VA 22031
   USA

   Email: turners@ieca.com







































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Full Copyright Statement

   Copyright (C) The IETF Trust (2008).

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