SIMPLE J. Rosenberg
Internet-Draft dynamicsoft
Expires: December 22, 2003 June 23, 2003
Extensible Markup Language (XML) Configuration Access Protocol (XCAP)
Usages for Setting Presence Authorization
draft-ietf-simple-xcap-auth-usage-00
Status of this Memo
This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 of RFC2026.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that other
groups may also distribute working documents as Internet-Drafts.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
The list of current Internet-Drafts can be accessed at http://
www.ietf.org/ietf/1id-abstracts.txt.
The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html.
This Internet-Draft will expire on December 22, 2003.
Copyright Notice
Copyright (C) The Internet Society (2003). All Rights Reserved.
Abstract
This document describes three usages of the Extensible Markup
Language (XML) Configuration Access Protocol (XCAP) that allow a
client to provide authorization decisions regarding watchers of their
presence. The first of these usages, called permission-statements,
contains statements about what permissions are to be granted to
watchers of presence. The second of these usages, called
compound-permissions, allows a client to define new permissions as
combinations of other defined permissions. The third usage, called
supported-permissions, allows a client to determine what permissions
are understood by the provider.
Rosenberg Expires December 22, 2003 [Page 1]
Internet-Draft XCAP Usage for Authorization June 2003
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . 4
2. Structuring Presence Authorization . . . . . . . . . . . 5
3. Terminology . . . . . . . . . . . . . . . . . . . . . . 6
4. Permission Statements . . . . . . . . . . . . . . . . . 7
4.1 Application Unique ID . . . . . . . . . . . . . . . . . 7
4.2 Structure of Permission Statements . . . . . . . . . . . 7
4.2.1 Applying Statements to Watchers . . . . . . . . . . . . 7
4.2.2 Specifying Permissions . . . . . . . . . . . . . . . . . 9
4.2.2.1 Acceptance Permissions . . . . . . . . . . . . . . . . . 10
4.2.2.2 Rule Permissions . . . . . . . . . . . . . . . . . . . . 12
4.2.2.2.1 Identifying Elements and Indicating Values . . . . . . . 13
4.2.2.2.2 Examples . . . . . . . . . . . . . . . . . . . . . . . . 14
4.2.2.3 Content Permissions . . . . . . . . . . . . . . . . . . 15
4.2.2.3.1 Examples . . . . . . . . . . . . . . . . . . . . . . . . 17
4.2.2.4 Transformational Permissions . . . . . . . . . . . . . . 18
4.2.2.4.1 Examples . . . . . . . . . . . . . . . . . . . . . . . . 18
4.3 Additional Constraints . . . . . . . . . . . . . . . . . 19
4.4 Naming Conventions . . . . . . . . . . . . . . . . . . . 20
4.5 Authorization Policies . . . . . . . . . . . . . . . . . 20
4.6 XML Schema . . . . . . . . . . . . . . . . . . . . . . . 20
5. Compound Permissions . . . . . . . . . . . . . . . . . . 27
5.1 Application Unique ID . . . . . . . . . . . . . . . . . 27
5.2 Structure of Compound Permissions . . . . . . . . . . . 27
5.3 Naming Conventions . . . . . . . . . . . . . . . . . . . 27
5.4 Authorization Policies . . . . . . . . . . . . . . . . . 27
5.5 XML Schema . . . . . . . . . . . . . . . . . . . . . . . 28
5.6 Example Document . . . . . . . . . . . . . . . . . . . . 28
6. Supported Permissions . . . . . . . . . . . . . . . . . 30
6.1 Application Unique ID . . . . . . . . . . . . . . . . . 30
6.2 Structure of Supported Permissions . . . . . . . . . . . 30
6.3 Naming Conventions . . . . . . . . . . . . . . . . . . . 31
6.4 Authorization Policies . . . . . . . . . . . . . . . . . 31
6.5 XML Schema . . . . . . . . . . . . . . . . . . . . . . . 31
6.6 Example Document . . . . . . . . . . . . . . . . . . . . 32
7. IANA Considerations . . . . . . . . . . . . . . . . . . 34
7.1 XCAP Application Usage IDs . . . . . . . . . . . . . . . 34
7.1.1 Permission Statements . . . . . . . . . . . . . . . . . 34
7.1.2 Compound Permissions . . . . . . . . . . . . . . . . . . 34
7.1.3 Supported Permissions . . . . . . . . . . . . . . . . . 34
7.2 URN Sub-Namespace Registrations . . . . . . . . . . . . 34
7.2.1 urn:ietf:params:xml:ns:permission-statements . . . . . . 34
7.2.2 urn:ietf:params:xml:ns:compound-permissions . . . . . . 35
7.2.3 urn:ietf:params:xml:ns:supported-permissions . . . . . . 36
7.3 XML Schema Registrations . . . . . . . . . . . . . . . . 37
7.3.1 Permissions Statements . . . . . . . . . . . . . . . . . 37
7.3.2 Compound Permissions . . . . . . . . . . . . . . . . . . 37
Rosenberg Expires December 22, 2003 [Page 2]
Internet-Draft XCAP Usage for Authorization June 2003
7.3.3 Supported Permissions . . . . . . . . . . . . . . . . . 37
Normative References . . . . . . . . . . . . . . . . . . 38
Informative References . . . . . . . . . . . . . . . . . 39
Author's Address . . . . . . . . . . . . . . . . . . . . 39
Intellectual Property and Copyright Statements . . . . . 40
Rosenberg Expires December 22, 2003 [Page 3]
Internet-Draft XCAP Usage for Authorization June 2003
1. Introduction
The Session Initiation Protocol (SIP) for Instant Messaging and
Presence (SIMPLE) specifications allow a user, called a watcher, to
subscribe to another user, called a presentity [12], in order to
learn their presence information [13]. This subscription is handed by
a presence agent. In order to process the subscription, the presence
agent must make a determination about whether the subscription is
authorized. This authorization decision includes whether or not to
accept the subscription, but also includes decisions about when the
watcher should receive notifications, and when it does receive them,
what the content of those notifications should be.
Typically, the authorization decision will be a combination of the
authorization policies of the provider, combined with the
authorization policices of the presentity. In order for the PA to
compute the final authorization decision, it needs access to the
presentity's authorization policies.
In order to provide this access, the XML Configuration Access
Protocol (XCAP) [2] is used. XCAP allows a client to manipulate XML
documents stored on a server. Those XML documents represent per-user
provisioning data on how an application should operate. XCAP has the
notion of an application usage, which is a definition of the XML
schema used by a particular application, along with other relevant
information. Each application usage is given a unique application
usage ID (AUID) which identifies it. This specification makes use of
three application usages.
Rosenberg Expires December 22, 2003 [Page 4]
Internet-Draft XCAP Usage for Authorization June 2003
2. Structuring Presence Authorization
This specification defines three application usages (each with their
own XML schema) that, put together, present a comprehensive solution
for allowing clients to specify authorization policies that a PA can
use when processing a subscription. The first of these application
usages has the AUID of permission-statements. This usage allows a
client to make statements about which permissions are granted to
which watchers. Each statement contains a definition of the watchers
to whom it applies, and then contains a list of permissions which are
granted to those watchers. The concept of a permission is central to
this specification. A permission is an atomic statement of consent or
denial. A permission can indicate a condition under which a
subscription is accepted or rejected, a condition under which a
notification is or is not sent, or a piece of information which is or
is not revealed in a presence document. The overall authorization for
a watcher is represented by the union of the permissions granted to
that watcher.
Permissions can be classified as either primitive or compound. A
primitive permission is one of the permissions defined in this
specification. A compound permission is a new permission that is
defined as a combination of other primitive or compound permissions.
As an example, the "grant-phone" permission might be a compound
permission which accepts the subscription, sends a watcher
notifications when the status of the user's phone changes, and those
notifications contain the status of the phone. As a result, to
facilitate ease of use, a second application usage is defined, which
allows a user to construct new compound permissions.
This specification contains a fairly broad set of primitive
permissions. It is anticipated that new ones will be standardized in
the future. It is also anticipated that vendors will define
proprietary permissions. In order for a client to connect to a
server, and achieve interoperability, it is neccesary for the client
to know what permissions are supported by the server. The third
application usage, supported-permissions, allows a client to read the
list of permissions understood by the server.
Rosenberg Expires December 22, 2003 [Page 5]
Internet-Draft XCAP Usage for Authorization June 2003
3. Terminology
In this document, the key words "MUST", "MUST NOT", "REQUIRED",
"SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY",
and "OPTIONAL" are to be interpreted as described in RFC 2119 [1] and
indicate requirement levels for compliant implementations.
Rosenberg Expires December 22, 2003 [Page 6]
Internet-Draft XCAP Usage for Authorization June 2003
4. Permission Statements
4.1 Application Unique ID
XCAP requires application usages to define a unique application usage
ID (AUID) in either the IETF tree or a vendor tree. This
specification defines the "permission-statements" AUID within the
IETF tree, via the IANA registration in Section 7.
4.2 Structure of Permission Statements
A permission statement is an XML [3] document that MUST be
well-formed and SHOULD be valid. Permission statement documents MUST
be based on XML 1.0 and MUST be encoded using UTF-8. This
specification makes use of XML namespaces for identifying permission
statement documents and document fragments. The namespace URI for
elements defined for this purpose is a URN [5], using the namespace
identifier 'ietf' defined by [7] and extended by [11]. This URN is:
urn:ietf:params:xml:ns:permission-statements
A permission statement document begins with the root element tag
"permission-statements". It consists of any number of "statement"
elements. Each statement element defines a set of permissions and
identifies to whom they are granted.
Each "statement" element has a single attribute:
id: This is a string which serves as a way to uniquely identify
statements in the document. The attribute MUST be unique amongst
all statement elements in the document. This attribute is
mandatory.
Each statement is composed of a single "applies-to" element and a
single "permissions" element. The "permissions" element is composed
of one or more elements that grant permissions.
4.2.1 Applying Statements to Watchers
The "applies-to" element defines the set of watchers to whom the
statement applies. It contains one or more "uri" elements, "domain"
elements, "on-list" elements or a single "any" element. The "uri"
element identifies a single watcher by specifying its URI. The
"domain" element says that the statement applies to all watchers from
the specified domain. The "on-list" element says that the statement
applies to all users on the specified presence list [16], identified
with an HTTP URI that points to the list. Finally, the "any" element
says that the statement applies to all watchers. Additional elements
Rosenberg Expires December 22, 2003 [Page 7]
Internet-Draft XCAP Usage for Authorization June 2003
can be added that express other ways of identifying the watchers to
whom the statement applies.
The "uri", "domain", "on-list" and "any" elements all have the
following attributes:
id: This is a string which serves as a way to uniquely identify an
instance of this element within the enclosing "applies-to"
element. The attribute MUST be unique amongst all elements of the
same name within the enclosing "applies-to" element. This
attribute is mandatory.
display-name: This is a string that contains a display name, suitable
for rendering to a human user, the identity of the user or domain
implied by the element. This attribute is optional.
lang: This attribute identifies the language used to represent the
display name. It is imported from the XML namespace. This
attribute is optional.
When a subscription arrives at the PA, the PA performs an
authentication operation to determine the identity of the watcher. It
then uses the "applies-to" element in each statement within the
presentity's document, and determines the set of statements that
apply to the watcher. It is possible that multiple statements can
match a single subscription. In that case, the union of the
permissions across those statements is applied to the subscription.
It is also possible that none of the statements match, in which case
the subscription is considered "pending".
OPEN ISSUE: Another model is that you take permissions for the
most specific match. I think union makes more sense in the model
where the entries in the statement are permissions.
For example, the following XML fragment includes two statements, one
that applies to the user joe@example.com, and another that applies to
example.com. When Joe subscribes, both statements match. Therefore,
he is granted the union of the permissions across the two statements.
Rosenberg Expires December 22, 2003 [Page 8]
Internet-Draft XCAP Usage for Authorization June 2003
<?xml version="1.0" encoding="UTF-8"?>
<permission-statements>
<statement id="as8f">
<applies-to>
<uri>sip:joe@example.com</uri>
</applies-to>
<permissions>
<!-- permissions for joe go here -->
</permissions>
</statement>
<statement id="kgg8a">
<applies-to>
<domain>example.com</domain>
</applies-to>
<permissions>
<!-- permissions for example.com go here -->
</permissions>
</statement>
</permission-statements>
4.2.2 Specifying Permissions
The remainder of the content of the "statement" element contains
specific permissions that are granted to watchers to whom the
statement applies. Each permission is represented by a single XML
element. Permissions can be primitive or they can be compound. A
primitive permission is one that explicitly defines the permission
that is being granted. A compound permission is a collection of other
permissions, both compound and primitive. Compound permissions are a
useful way of grouping permissions in order to simplify the overall
user interface.
Primitive permissions can be grouped broadly into three categories:
1. Acceptance permissions allow the watcher to subscribe. Without an
acceptance permission, a subscription is rejected outright.
2. Rule permissions indicate conditions on which a notification is
sent. Whenever there is a change in the presence of a user, the
presence agent will check to see if any rule permissions apply.
If any of them do, a notification is sent. This of course,
assumes that the subscription had an acceptance permission in the
Rosenberg Expires December 22, 2003 [Page 9]
Internet-Draft XCAP Usage for Authorization June 2003
first place.
3. Content permissions indicate which information the watcher is
permitted to see, in the event a notification is sent in the
first place (based on the rule permissions).
4. Transformational permissions indicate any changes that should be
made to information sent to a watcher. This, of course, assumes
that the information is to be transmitted to the watcher in the
first place (based on the content permissions).
4.2.2.1 Acceptance Permissions
Acceptance permissions grant the ability of the watcher to subscribe
to the presentity. Without an acceptance permission, none of the
other permissions make any sense. There are only two primitive
acceptance permissions, each of which is an XML element. These are
"accept" and "accept-if". The "accept" element has no content and no
attributes. It simply grants permission to the watcher to subscribe.
Only one such element can be present in any statement. The
"accept-if" element also grants permission to subscribe, but the
granting of this permissions is predicated on some condition. The
content of the "accept-if" element is a condition element. Condition
elements describe characteristics of the subscription, or of the
operating environment of the server, which are either true or false.
If the condition within the "accept-if" element is true, an
acceptance permission is granted.
The first condition element is "and". This condition evaluates to
true if all of the conditions contained within it evaluate to true.
The second condition element is "or". This condition evaluates to
true if any of the conditions contained within it evaluate to true.
The third condition element is "not". This condition evaluates to
true if the single condition contained within it evaluates to false.
These basic boolean types, which can themselves be composed, allow
for statements of fairly complex conditions under which a
subscription should be granted.
The following represent the "atomic" conditions which can be checked:
requested-namespace: This element has a value that contains a URI
identifying an XML namespace. The condition evaluates to true if
the subscription request explicitly contained a filter which
requested the PA to include elements from that namespace within
its notifications.
Rosenberg Expires December 22, 2003 [Page 10]
Internet-Draft XCAP Usage for Authorization June 2003
requested-element: This element has a value that contains a string
identifying an XML element. The condition evaluates to true if the
subscription request explicitly contained a filter which requested
the PA to include elements of that name within its notifications.
requested-tuple: This element has a value that contains a string
whose value is a tuple ID [14]. The condition evaluates to true if
the subscription request explicitly contained a filter which
requested the PA to include tuples with that tuple ID within its
notifications.
duration: This element has a value that contains an integer,
representing a number of seconds. The condition evaluates to true
if the subscription request was for a duration less than or equal
to this value. This condition is handy for allowing watchers the
ability only to fetch presence documents. This is done by setting
this condition to zero.
auth-mechanism: This element contains an enumerated type that
describes authentication mechanisms. The defined values are none,
digest (referring to the HTTP digest [8] mechanism used in RFC
3261 [9]), smime (referring to SIP's S/MIME authentication), tls
(meaning that the watcher authenticated themself using a client
certificate in a mutual TLS exchange with the server), and
p-asserted-id (as defined in RFC 3325 [15]). The condition
evaluates to true if the client was authenticated using the listed
algorithm.
anonymous: This element contains no values. The condition evaluates
to true if the watcher is anonymous. They are considered anonymous
if the From header field of the request is equal to "Anonymous".
Note that a user can be anonymous and also have authenticated
themselves with digest. This occurs when the "anonymous" username
and password, as defined in RFC 3261 [9], are used.
can-encrypt: This element contains no values. The condition evaluates
to true if it is possible to encrypt, using S/MIME, notifications
sent to this watcher. Generally, this can be determined when the
Accept header field in the subscription indicates support for the
application/pkcs7-mime [10] MIME type.
As an example, the following statement grants permission for watcher
sip:joe@example.com to subscribe if he authenticates with digest and
doesn't ask to be notified of phone state:
Rosenberg Expires December 22, 2003 [Page 11]
Internet-Draft XCAP Usage for Authorization June 2003
<?xml version="1.0" encoding="UTF-8"?>
<permission-statements>
<statement id="as8f">
<applies-to>
<uri>sip:joe@example.com</uri>
</applies-to>
<permissions
<accept-if>
<and>
<auth-mechanism>digest</auth-mechanism>
<not><requested-namespace>
urn:ietf:params:xml:ns:pidf:common-phone-state
</requested-namespace></not>
</and>
</accept-if>
</permissions>
</statement>
</permission-statements>
OPEN ISSUE: It is possible to eliminate the notion of "applies-to"
by folding it into accept-if, and allowing conditions to be used
in granting other forms of permissions. I preferred the model of a
separate applies-to because it allowed us to break the XML
document into sets of statements, each of which could apply to
totally different watchers, and therefore manipulated
independently of each other. This made it more amenable to usage
with XCAP without requiring locks. In terms of allowing conditions
to be used with the other permission types, that can be added in
the future, but seemed to be overly complex for this
specification.
4.2.2.2 Rule Permissions
Rule permissions grant the watcher the ability to receive a
notification when there is a state change of some sort. Each
permission specifies a condition under which a state change will
cause a notification to be sent. Generally, these conditions are
checks on the values of the attributes that have changed.
Each permission is associated with an XML element. The elements
defined in this specification are:
Rosenberg Expires December 22, 2003 [Page 12]
Internet-Draft XCAP Usage for Authorization June 2003
any-event: This element has no attributes and no content. It grants
permission for the watcher to see all presence state changes.
enter-state: This element indicates that a watcher is permitted to
receive notifications when a particular piece of presence
information changes to the specified value. The content of this
element is a "state" element. A "state" element has two parts. One
identifies the particular piece of presence information, and the
other specifies its value.
exit-state: This element indicates that a watcher is permitted to
receive notifications when a particular piece of presence
information changes from the specified value. The content of this
element is also a "state" element.
transition: This element indicates that a watcher is permitted to
receive notifications when a particular piece of presence
information changes from one value to another value. The content
of this element are three XML elements - one that identifies the
piece of presence information (using either the "element-name" or
"element-path" elements, discussed below), one (called "value")
that indicates the original value, and another "value" element
that indicates the value that it changed to.
change-in: This element indicates that a watcher is permitted to
receive notifications triggered by a change in the value of the
specified piece of presence information. The value of the element
is an identifier for a particular piece of presence information
(using either the "element-name" or "element-path" elements).
equals: This element indicates that a watcher is permitted to receive
notifications while a particular piece of presence information has
a particular value. As an example, a presentity can indicate that
a watcher should receive notifications of changes in phone state
while the basic status is open, but notifications are not sent
when the value of basic status is closed. The content of this
element is a "state" element.
subscription-state: This element indicates that a watcher is
permitted to receive notifications that convey changes in the
state of the subscription itself. It has no attributes or content.
4.2.2.2.1 Identifying Elements and Indicating Values
A key component of most of these rule permissions is the ability to
identify a piece of presence information and indicate a value for it.
This function is provided by several XML elements.
Rosenberg Expires December 22, 2003 [Page 13]
Internet-Draft XCAP Usage for Authorization June 2003
The first issue is to identify a piece of presence information. This
specification provides two ways to identify a piece of presence
information. The first is with the "element-name" element. This
element, which has no attributes, contains, as a value, the name of
an XML element. This is a reference to any instances in the presence
document where this element would occur. It is also a reference to
the ways in which that element is used as an input to the computation
of other elements. For example, if the rule permission says that a
watcher will receive notifications when "call-state" elements change,
that implies that they are also permitted to receive notifications
when there is a change in some other element, such as the PIDF
"basic" element, when that change is a direct result of a change in
the "call-state" element. In this regard, the "element-name" doesn't
address a specific element in an XML document as much as a raw piece
of presence data.
The second way to address an XML element is with XPath [4]. This is
done using the "element-path" element. This element has no
attributes, and its content is a valid location-set XPath expression
that points to components of a presence document. In this case, the
expression refers to the actual XML document components, rather than
the raw data they represent.
The "state" element is composed of either the "element-name" or
"element-path" elements, followed by the "value" element. The "value"
element has no attributes, and its content is a string containing the
value of the element identified by the "element-name" or
"element-path". In the latter case, the XPath expression MUST refer
to a single attribute or a single element with text content.
4.2.2.2.2 Examples
The following XML document specifies a rule permission that specifies
that a watcher should receive notifications only when the basic
status changes:
Rosenberg Expires December 22, 2003 [Page 14]
Internet-Draft XCAP Usage for Authorization June 2003
<?xml version="1.0" encoding="UTF-8"?>
<permission-statements
xmlns:pidf="urn:ietf:params:xml:ns:pidf">
<statement id="as8f">
<applies-to>
<uri>sip:joe@example.com</uri>
</applies-to>
<permissions>
<accept/>
<change-in>pidf:basic</change-in>
</permissions>
</statement>
</permission-statements>
This document says that a watcher should receive notifications only
when the "placetype" element is equal to "home". This is useful as a
permission to apply to watchers that are friends - they will receive
no notifications while you are at work, and only receive them when
you are at home:
<?xml version="1.0" encoding="UTF-8"?>
<permission-statements
xmlns:rpids="urn:ietf:params:xml:ns:sip-rpids">
<statement id="as8f">
<applies-to>
<uri>sip:joe@example.com</uri>
</applies-to>
<permissions>
<accept/>
<equals>
<state>
<element-name>rpids:placetype</element-name>
<value>home</value>
</state>
<equals>
</permissions>
</statement>
</permission-statements>
4.2.2.3 Content Permissions
Content permissions specify the information that is to be sent to a
Rosenberg Expires December 22, 2003 [Page 15]
Internet-Draft XCAP Usage for Authorization June 2003
watcher. Each permission specifies a piece of information that is to
be sent, or to be used in general in the computation of the presence
document. The defined permissions are:
all-content: This permission specifies that all presence information
can be sent. The element has no attributes or value.
show-contact-element: This permission specifies that the contact
component of the tuple can be sent. The element has no attributes
or value.
show-note: This permission specifies that the note component of the
tuple can be sent. The element has no attributes or value.
show-tuple: This permission specifies that the tuple identified by
the element can be sent to the watcher. The element has not
attributes. Its content is a string that matches the tuple "id"
attribute in the presence document.
show-element: This permission specifies that the XML element
identified by "show-element" can be sent to the watcher. The
content of "show-element" is either the "element-name" or
"element-path" elements as defined above. If the "element-name" is
used, it means that the specified element can be "presented" to
the watcher, where "presented" implies that they are either
present in the XML document, or used as part of the derivation of
other presence data. Otherwise, if the "element-path" is used, it
means that the specified element can be present in the document
sent to the watcher.
show-namespace: This permission specifies that elements and
attributes in the presence document within the specified namespace
can be presented to the watcher. Here, "presented" implies that
they are either present in the XML document, or used as part of
the derivation of other presence data.
show-values: This permission specifies that an element of the
presence document can only be "presented", per the above
definition, if it has the specified value. The content of this
element is an "element-name" element followed by a "value"
element.
encrypt: This permission specifies that the presence document should
be sent to the watcher encrypted. It should never be present in a
statement without the presence of an "accept-if" element which
conditions acceptance of the subscription on the ability of the
watcher to receive encrypted presence documents.
Rosenberg Expires December 22, 2003 [Page 16]
Internet-Draft XCAP Usage for Authorization June 2003
4.2.2.3.1 Examples
The following example specifies that a watcher is only allowed to see
baseline pidf information:
<?xml version="1.0" encoding="UTF-8"?>
<permission-statements
xmlns:pidf="urn:ietf:params:xml:ns:pidf">
<statement id="as8f">
<applies-to>
<uri>sip:joe@example.com</uri>
</applies-to>
<permissions>
<accept/>
<show-namespace>urn:ietf:params:xml:ns:pidf</show-namespace>
<any-event/>
</permissions>
</statement>
</permission-statements>
The following example shows that the watcher is allowed to see PIDF
information along with the placetype element from RPIDS:
<?xml version="1.0" encoding="UTF-8"?>
<permission-statements
xmlns:pidf="urn:ietf:params:xml:ns:pidf"
xmlns:rpids="urn:ietf:params:xml:ns:sip-rpids">
<statement id="as8f">
<applies-to>
<uri>sip:joe@example.com</uri>
</applies-to>
<permissions>
<accept/>
<show-namespace>urn:ietf:params:xml:ns:pidf</show-namespace>
<show-element>
<element-name>rpids:placetype</element-name>
</show-element>
<any-event/>
</permissions>
</statement>
</permission-statements>
Rosenberg Expires December 22, 2003 [Page 17]
Internet-Draft XCAP Usage for Authorization June 2003
4.2.2.4 Transformational Permissions
Transformational permissions specify explicit ways in which the
presence document is changed before it is presented to a watcher.
Generally, this is useful for allowing a presentity to "lie" in the
information sent to a watcher.
The permissions defined in this specification are:
set-document: This permission indicates that the specified presence
document should be sent to the watcher. The value of the element
is a valid PIDF document.
set-element: This permission indicates that the specified element
should be set to the specified value. The value of this element is
a "state" element.
change-element-from: This permission indicates that the specified
element, when its value is as indicated, should change to the
specified value. Its content is either "element-name" or
"element-path", followed by two "value" elements.
When the transformations specified by these attributes overlap, the
sequence of the operations is important. The "change-element-from"
are done first, followed by "set-element", followed by
"set-document".
4.2.2.4.1 Examples
The following document specifies that the "activity" element from
rpids should always be set to "active":
Rosenberg Expires December 22, 2003 [Page 18]
Internet-Draft XCAP Usage for Authorization June 2003
<?xml version="1.0" encoding="UTF-8"?>
<permission-statements
xmlns:pidf="urn:ietf:params:xml:ns:pidf"
xmlns:rpids="urn:ietf:params:xml:ns:sip-rpids">
<statement id="as8f">
<applies-to>
<uri>sip:joe@example.com</uri>
</applies-to>
<permissions>
<accept/>
<show-namespace>urn:ietf:params:xml:ns:pidf</show-namespace>
<show-namespace>urn:ietf:params:xml:ns:sip-rpids</show-namespace>
<any-event/>
<set-element>
<state>
<element-name>rpids:activity</element-name>
<value>active</value>
</state>
</set-element>
</permissions>
</statement>
</permission-statements>
4.3 Additional Constraints
The following are additional constraints not described by the schema:
o The content of an "element-path" element MUST be a valid Xpath
expression that contains a location-set. [[OPEN ISSUE: Is there a
way to express this in the schema?]]
o The content of an "element-name" element indicates the name of an
XML element, and may be fully qualified (i.e., prefixed with a
namespace identifier followed by a colon).
o The value of the "domain" element MUST be compliant to the BNF for
"host" as defined in RFC 3261 [9].
o The value of the "on-list" element MUST be a valid HTTP URI that
represents a presence list, as defined in [16].
o TODO: Complete this list.
Rosenberg Expires December 22, 2003 [Page 19]
Internet-Draft XCAP Usage for Authorization June 2003
4.4 Naming Conventions
When a presence agent receives a subscription for some user foo
within a domain, it will look for all documents within http://[xcap
root services uri]/permission-statements/users/foo, and use all
documents found beneath that point to guide authorization policy.
4.5 Authorization Policies
This application usage does not modify the default XCAP authorization
policy, which is that only a user can read, write or modify their own
documents. A server can allow priveleged users to modify documents
that they don't own, but the establishment and indication of such
policies is outside the scope of this document.
4.6 XML Schema
<?xml version="1.0" encoding="UTF-8"?>
<!-- edited with XML Spy v4.3 U (http://www.xmlspy.com) by Jonathan Rosenberg (Dynamicsoft Inc) -->
<xs:schema targetNamespace="urn:ietf:params:xml:ns:permission-statements" xmlns="urn:ietf:params:xml:ns:permission-statements" xmlns:pidf="urn:ietf:params:xml:ns:pidf" xmlns:xs="http://www.w3.org/2001/XMLSchema" elementFormDefault="qualified" attributeFormDefault="unqualified">
<xs:import namespace="http://www.w3.org/XML/1998/namespace" schemaLocation="http://www.w3.org/2001/xml.xsd"/>
<xs:import namespace="urn:ietf:params:xml:ns:pidf" schemaLocation="pidf.xsd"/>
<xs:element name="permission-statements">
<xs:annotation>
<xs:documentation>Comment describing your root element</xs:documentation>
</xs:annotation>
<xs:complexType>
<xs:sequence minOccurs="0" maxOccurs="unbounded">
<xs:element name="statement">
<xs:complexType>
<xs:sequence>
<xs:element name="applies-to" type="applies-toType"/>
<xs:element name="permissions" type="permissionsType"/>
</xs:sequence>
<xs:attribute name="id" type="xs:string" use="required"/>
</xs:complexType>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:complexType name="permissionsType">
<xs:sequence>
<xs:sequence>
<xs:annotation>
<xs:documentation>Acceptance Permissions</xs:documentation>
</xs:annotation>
<xs:element name="accept" minOccurs="0"/>
Rosenberg Expires December 22, 2003 [Page 20]
Internet-Draft XCAP Usage for Authorization June 2003
<xs:element name="accept-if" minOccurs="0" maxOccurs="unbounded"/>
</xs:sequence>
<xs:sequence>
<xs:annotation>
<xs:documentation>Rule Permissions</xs:documentation>
</xs:annotation>
<xs:element name="any-event" minOccurs="0"/>
<xs:sequence>
<xs:element name="enter-state" minOccurs="0" maxOccurs="unbounded">
<xs:complexType>
<xs:sequence>
<xs:element name="state" type="stateType"/>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="exit-state" minOccurs="0" maxOccurs="unbounded">
<xs:complexType>
<xs:sequence>
<xs:element name="state" type="stateType"/>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="transition" minOccurs="0" maxOccurs="unbounded">
<xs:complexType>
<xs:sequence>
<xs:choice>
<xs:element name="element-name" type="xs:string"/>
<xs:element name="element-path" type="xs:string"/>
</xs:choice>
<xs:element name="value" type="xs:string"/>
<xs:element name="value" type="xs:string"/>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="change-in" minOccurs="0" maxOccurs="unbounded">
<xs:complexType>
<xs:choice>
<xs:element name="element-name" type="xs:string"/>
<xs:element name="element-type" type="xs:string"/>
</xs:choice>
</xs:complexType>
</xs:element>
<xs:element name="equals" minOccurs="0" maxOccurs="unbounded">
<xs:complexType>
<xs:sequence>
<xs:element name="state" type="stateType"/>
</xs:sequence>
</xs:complexType>
Rosenberg Expires December 22, 2003 [Page 21]
Internet-Draft XCAP Usage for Authorization June 2003
</xs:element>
<xs:element name="subscription-state" minOccurs="0"/>
</xs:sequence>
</xs:sequence>
<xs:sequence>
<xs:annotation>
<xs:documentation>Content Permissions</xs:documentation>
</xs:annotation>
<xs:element name="all-content" minOccurs="0"/>
<xs:sequence>
<xs:element name="show-contact-element" minOccurs="0"/>
<xs:element name="show-note" minOccurs="0"/>
<xs:element name="show-tuple" type="xs:string" minOccurs="0" maxOccurs="unbounded"/>
<xs:element name="show-element" minOccurs="0" maxOccurs="unbounded">
<xs:complexType>
<xs:choice>
<xs:element name="element-name" type="xs:string"/>
<xs:element name="element-path" type="xs:string"/>
</xs:choice>
</xs:complexType>
</xs:element>
<xs:element name="show-namespace" type="xs:string" minOccurs="0" maxOccurs="unbounded"/>
<xs:element name="show-values" minOccurs="0" maxOccurs="unbounded">
<xs:complexType>
<xs:sequence>
<xs:element name="element-name" type="xs:string"/>
<xs:element name="value" type="xs:time"/>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="encrypt" minOccurs="0"/>
</xs:sequence>
</xs:sequence>
<xs:sequence>
<xs:annotation>
<xs:documentation>Transformational Permissions</xs:documentation>
</xs:annotation>
<xs:element name="set-document" minOccurs="0">
<xs:complexType>
<xs:sequence>
<xs:element ref="pidf:presence"/>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="set-element" minOccurs="0" maxOccurs="unbounded">
<xs:complexType>
<xs:sequence>
<xs:element name="state" type="stateType"/>
Rosenberg Expires December 22, 2003 [Page 22]
Internet-Draft XCAP Usage for Authorization June 2003
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="change-element-from" minOccurs="0" maxOccurs="unbounded">
<xs:complexType>
<xs:sequence>
<xs:choice>
<xs:element name="element-name" type="xs:string"/>
<xs:element name="element-path" type="xs:string"/>
</xs:choice>
<xs:element name="value" type="xs:string"/>
<xs:element name="value" type="xs:string"/>
</xs:sequence>
</xs:complexType>
</xs:element>
</xs:sequence>
<xs:any namespace="##other" processContents="lax" minOccurs="0" maxOccurs="unbounded">
<xs:annotation>
<xs:documentation>Compound Permissions</xs:documentation>
</xs:annotation>
</xs:any>
</xs:sequence>
</xs:complexType>
<xs:complexType name="applies-toType">
<xs:choice>
<xs:element name="any">
<xs:complexType>
<xs:attribute name="id" type="xs:string" use="required"/>
<xs:attribute name="displayName" type="xs:string" use="optional"/>
<xs:attribute ref="xml:lang"/>
</xs:complexType>
</xs:element>
<xs:sequence>
<xs:element name="uri" minOccurs="0" maxOccurs="unbounded">
<xs:complexType>
<xs:simpleContent>
<xs:extension base="xs:anyURI">
<xs:attribute name="id" type="xs:string" use="required"/>
<xs:attribute name="displayName" type="xs:string" use="optional"/>
<xs:attribute ref="xml:lang"/>
</xs:extension>
</xs:simpleContent>
</xs:complexType>
</xs:element>
<xs:element name="domain" minOccurs="0" maxOccurs="unbounded">
<xs:complexType>
<xs:simpleContent>
<xs:extension base="xs:string">
Rosenberg Expires December 22, 2003 [Page 23]
Internet-Draft XCAP Usage for Authorization June 2003
<xs:attribute name="id" type="xs:string" use="required"/>
<xs:attribute name="displayName" type="xs:string" use="optional"/>
<xs:attribute ref="xml:lang" use="optional"/>
</xs:extension>
</xs:simpleContent>
</xs:complexType>
</xs:element>
<xs:element name="on-list" minOccurs="0" maxOccurs="unbounded">
<xs:complexType>
<xs:simpleContent>
<xs:extension base="xs:anyURI">
<xs:attribute name="id" type="xs:string" use="required"/>
<xs:attribute name="displayName" type="xs:string" use="optional"/>
<xs:attribute ref="xml:lang" use="optional"/>
</xs:extension>
</xs:simpleContent>
</xs:complexType>
</xs:element>
</xs:sequence>
</xs:choice>
</xs:complexType>
<xs:complexType name="accept-ifType">
<xs:choice>
<xs:element name="and" type="andType"/>
<xs:element name="or" type="orType"/>
<xs:element name="not" type="notType"/>
<xs:element name="requested-namespace" type="xs:string"/>
<xs:element name="requested-element" type="xs:string"/>
<xs:element name="requested-tuple" type="xs:string"/>
<xs:element name="duration" type="xs:nonNegativeInteger"/>
<xs:element name="auth-mechanism" type="auth-mechanismType"/>
<xs:element name="anonymous"/>
<xs:element name="can-encrypt"/>
</xs:choice>
</xs:complexType>
<xs:simpleType name="auth-mechanismType">
<xs:restriction base="xs:string">
<xs:enumeration value="none"/>
<xs:enumeration value="digest"/>
<xs:enumeration value="smime"/>
<xs:enumeration value="tls"/>
<xs:enumeration value="p-asserted-id"/>
</xs:restriction>
</xs:simpleType>
<xs:complexType name="andType">
<xs:sequence maxOccurs="unbounded">
<xs:choice>
<xs:element name="and" type="andType"/>
Rosenberg Expires December 22, 2003 [Page 24]
Internet-Draft XCAP Usage for Authorization June 2003
<xs:element name="or" type="orType"/>
<xs:element name="not" type="notType"/>
<xs:element name="requested-namespace" type="xs:string"/>
<xs:element name="requested-element" type="xs:string"/>
<xs:element name="requested-tuple" type="xs:string"/>
<xs:element name="duration" type="xs:nonNegativeInteger"/>
<xs:element name="auth-mechanism" type="auth-mechanismType"/>
<xs:element name="anonymous"/>
<xs:element name="can-encrypt"/>
</xs:choice>
</xs:sequence>
</xs:complexType>
<xs:complexType name="orType">
<xs:sequence maxOccurs="unbounded">
<xs:choice>
<xs:element name="and" type="andType"/>
<xs:element name="or" type="orType"/>
<xs:element name="not" type="notType"/>
<xs:element name="requested-namespace" type="xs:string"/>
<xs:element name="requested-element" type="xs:string"/>
<xs:element name="requested-tuple" type="xs:string"/>
<xs:element name="duration" type="xs:nonNegativeInteger"/>
<xs:element name="auth-mechanism" type="auth-mechanismType"/>
<xs:element name="anonymous"/>
<xs:element name="can-encrypt"/>
</xs:choice>
</xs:sequence>
</xs:complexType>
<xs:complexType name="notType">
<xs:choice>
<xs:element name="and" type="andType"/>
<xs:element name="or" type="orType"/>
<xs:element name="not" type="notType"/>
<xs:element name="requested-namespace" type="xs:string"/>
<xs:element name="requested-element" type="xs:string"/>
<xs:element name="requested-tuple" type="xs:string"/>
<xs:element name="duration" type="xs:nonNegativeInteger"/>
<xs:element name="auth-mechanism" type="auth-mechanismType"/>
<xs:element name="anonymous"/>
<xs:element name="can-encrypt"/>
</xs:choice>
</xs:complexType>
<xs:complexType name="stateType">
<xs:sequence>
<xs:choice>
<xs:element name="element-name" type="xs:string"/>
<xs:element name="element-path" type="xs:string"/>
</xs:choice>
Rosenberg Expires December 22, 2003 [Page 25]
Internet-Draft XCAP Usage for Authorization June 2003
<xs:element name="value" type="xs:string"/>
</xs:sequence>
</xs:complexType>
</xs:schema>
TODOS: need to add points of extensibility.
Rosenberg Expires December 22, 2003 [Page 26]
Internet-Draft XCAP Usage for Authorization June 2003
5. Compound Permissions
Compound permissions allow a user to specify new permissions that are
a combination of primitive and compound permissions. Compound
permissions can be used within permission statements.
5.1 Application Unique ID
XCAP requires application usages to define a unique application usage
ID (AUID) in either the IETF tree or a vendor tree. This
specification defines the "compound-permissions" AUID within the IETF
tree, via the IANA registration in Section 7.
5.2 Structure of Compound Permissions
A compound permission is an XML [3] document that MUST be well-formed
and SHOULD be valid. Compound permission documents MUST be based on
XML 1.0 and MUST be encoded using UTF-8. This specification makes use
of XML namespaces for identifying compound permission documents and
document fragments. The namespace URI for elements defined for this
purpose is a URN [5], using the namespace identifier 'ietf' defined
by [7] and extended by [11]. This URN is:
urn:ietf:params:xml:ns:compound-permissions
A compound permission document begins with the root element tag
"compound-permissions". It consists of any number of
"compound-permission" elements. Each "compound-permission" defines a
new compound permission. It is a mandatory attribute "name" which
MUST be unique across all other "name" attributes within the
document. It serves as a unique handle to the compound permission.
A compound-permission is composed of a "permission-name" element,
containing a string value, which presents the name of the compound
permission. This is then followed by a "permissions" element, which
contains the permissions associated with the new compound permission.
5.3 Naming Conventions
When a presence agent receives a subscription for some user foo
within a domain, it will look for all documents within http://[xcap
root services uri]/compound-permissions/users/foo, and use all
documents found beneath that point as definitions of valid compound
permissions.
5.4 Authorization Policies
This application usage does not modify the default XCAP authorization
Rosenberg Expires December 22, 2003 [Page 27]
Internet-Draft XCAP Usage for Authorization June 2003
policy, which is that only a user can read, write or modify their own
documents. A server can allow priveleged users to modify documents
that they don't own, but the establishment and indication of such
policies is outside the scope of this document.
5.5 XML Schema
<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:ps="urn:ietf:params:xml:ns:permission-statements" xmlns:xs="http://www.w3.org/2001/XMLSchema" elementFormDefault="qualified" attributeFormDefault="unqualified">
<xs:import namespace="urn:ietf:params:xml:ns:permission-statements"/>
<xs:element name="compound-permissions">
<xs:annotation>
<xs:documentation>A series of compound permissions</xs:documentation>
</xs:annotation>
<xs:complexType>
<xs:sequence maxOccurs="unbounded">
<xs:element name="compound-permission">
<xs:complexType>
<xs:sequence>
<xs:element name="name" type="xs:string"/>
<xs:element name="permissions" type="ps:permissionsType"/>
</xs:sequence>
<xs:attribute name="name" type="xs:string" use="required"/>
</xs:complexType>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
</xs:schema>
5.6 Example Document
This example document defines a new compound permission, called
friends, and associates some permissions with it.
Rosenberg Expires December 22, 2003 [Page 28]
Internet-Draft XCAP Usage for Authorization June 2003
<?xml version="1.0" encoding="UTF-8"?>
<compound-permissions
xmlns:ps="urn:ietf:params:xml:ns:permission-statements"
elementFormDefault="qualified"
attributeFormDefault="unqualified">
<compound-permission name="p1">
<name>friends</name>
<permissions>
<accept/>
<equals>
<state>
<element-name>rpids:placetype</element-name>
<value>home</value>
</state>
<equals>
<all-content/>
</permissions>
</compound-permission>
</compound-permissions>
Rosenberg Expires December 22, 2003 [Page 29]
Internet-Draft XCAP Usage for Authorization June 2003
6. Supported Permissions
Supported permissions allow a presentity to determine what the
capabilities of the PA are, in terms of expressing authorization
policy. This capability is expressed as a list of primitive
permissions, primitive conditions, and compound permissions. When a
client starts up, it reads this set of permissions from a well known
URI (see Section Section 6.3). It then knows which permissions, both
primitive and compound, that it can include in its permission
statements.
6.1 Application Unique ID
XCAP requires application usages to define a unique application usage
ID (AUID) in either the IETF tree or a vendor tree. This
specification defines the "supported-permissions" AUID within the
IETF tree, via the IANA registration in Section 7.
6.2 Structure of Supported Permissions
A supported permission is an XML [3] document that MUST be
well-formed and SHOULD be valid. Supported permission documents MUST
be based on XML 1.0 and MUST be encoded using UTF-8. This
specification makes use of XML namespaces for identifying supported
permission documents and document fragments. The namespace URI for
elements defined for this purpose is a URN [5], using the namespace
identifier 'ietf' defined by [7] and extended by [11]. This URN is:
urn:ietf:params:xml:ns:supported-permissions
A supported permission document begins with the root element tag
"supported-permissions". It consists of one "primitive-permissions"
element, zero or one "conditions" elements and zero or one
"compound-permissions" elements.
The "primitive-permissions" element has, for its content, a
"permissions" element. This element contains a valid permission
statement which purposefully includes all primitive permissions that
are supported by the server. All PA's which allow for xcap-based
configuration of authorization MUST support, at a minimum, the
"accept", "any-event" and "all-content" primitive permissions.
The "conditions" element contains a sequence of conditions which can
be used within the "accept-if" element. Clearly, the "conditions"
element will not be present if "accept-if" is not listed as a
supported permission. There is no minimum requirement for a PA in
terms of the conditions that need to be supported.
Rosenberg Expires December 22, 2003 [Page 30]
Internet-Draft XCAP Usage for Authorization June 2003
The "compound-permissions" element is a sequence of compound
permissions supported by the server. Each one, described by a
"compound-permission" element, has a "name" and "description". The
"name" contains the name of the permission, and "description" is a
textual definition of the permission, meant for human consumption.
This is helpful in cases where the compound permissions are not
understood by the client. The descriptions can be rendered to the
human user, so that they can make a choice in the application of a
permission.
6.3 Naming Conventions
When a client starts, it can fetch the permissions understood by the
server in one of two places. If the server capabilities differ on a
user by user basis, the supported permissions for user foo can be
found in http://[xcap root services uri]/supported-permissions/users/
foo/sp.xml. A client SHOULD check this file first. If this document
doesn't exist, the client should next check for the system wide
permissions by checking http://[xcap root services uri]/
supported-permissions/global/sp.xml.
6.4 Authorization Policies
This application usage does not modify the default XCAP authorization
policy, which is that only a user can read, write or modify their own
documents. A server can allow priveleged users to modify documents
that they don't own, but the establishment and indication of such
policies is outside the scope of this document.
6.5 XML Schema
<?xml version="1.0" encoding="UTF-8"?>
<xs:schema
targetNamespace="urn:ietf:params:xml:ns:supported-permissions"
xmlns:xs="http://www.w3.org/2001/XMLSchema"
xmlns:ps="urn:ietf:params:xml:ns:permission-statements"
elementFormDefault="qualified"
attributeFormDefault="unqualified">
<xs:import namespace="urn:ietf:params:xml:ns:permission-statements"/>
<xs:element name="supported-permissions">
<xs:complexType>
<xs:sequence>
<xs:element name="primitive-permissions">
<xs:complexType>
<xs:sequence>
<xs:element name="permissions" type="ps:permissionsType"/>
Rosenberg Expires December 22, 2003 [Page 31]
Internet-Draft XCAP Usage for Authorization June 2003
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="conditions" minOccurs="0">
<xs:complexType>
<xs:sequence>
<xs:element name="condition" type="xs:string"
maxOccurs="unbounded"/>
</xs:sequence>
</xs:complexType>
</xs:element>
<xs:element name="compound-permissions" minOccurs="0">
<xs:complexType>
<xs:sequence minOccurs="0" maxOccurs="unbounded">
<xs:element name="compound-permission">
<xs:complexType>
<xs:sequence>
<xs:element name="name" type="xs:string"/>
<xs:element name="description" type="xs:string"/>
</xs:sequence>
</xs:complexType>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
</xs:schema>
6.6 Example Document
This example document describes a PA that allows very simple
primitive types. Instead, it defines several compound ones that are
the preferred way for clients to express permissions.
Rosenberg Expires December 22, 2003 [Page 32]
Internet-Draft XCAP Usage for Authorization June 2003
<?xml version="1.0" encoding="UTF-8"?>
<supported-permissions
xmlns:ps="urn:ietf:params:xml:ns:permission-statements"
elementFormDefault="qualified"
attributeFormDefault="unqualified">
<primitive-permissions>
<permissions>
<accept/>
<any-event/>
<all-content/>
</permissions>
</primitive-permissions>
<compound-permissions>
<compound-permission>
<name>low</name>
<description>This represents low security. Use
this with people you don't know.</description>
</compound-permission>
<compound-permission>
<name>high</name>
<description>This represents high security. Use
this with people you trust.</description>
</compound-permission>
</compound-permissions>
</supported-permissions>
Rosenberg Expires December 22, 2003 [Page 33]
Internet-Draft XCAP Usage for Authorization June 2003
7. IANA Considerations
There are several IANA considerations associated with this
specification.
7.1 XCAP Application Usage IDs
This section registers three XCAP Application Usage IDs (AUID)
according to the IANA procedures defined in [2].
7.1.1 Permission Statements
Name of the AUID: permission-statements
Description: Permission-statements are documents that describe the
permissions that a presentity [12] has granted to users that seek
to watch their presence.
7.1.2 Compound Permissions
Name of the AUID: compound-permissions
Description: Compound permissions are documents that describe new
types of permissions which can be granted to watchers [12] of the
presence of a user.
7.1.3 Supported Permissions
Name of the AUID: supported-permissions
Description: Supported permissions are documents that describe the
types of permissions which are supported by a presence agent [13].
These permissions specify the information that watchers [12] of
presence are allowed to see.
7.2 URN Sub-Namespace Registrations
This section registers several new XML namespaces, as per the
guidelines in [11]
7.2.1 urn:ietf:params:xml:ns:permission-statements
URI: The URI for this namespace is
urn:ietf:params:xml:ns:permission-statements.
Rosenberg Expires December 22, 2003 [Page 34]
Internet-Draft XCAP Usage for Authorization June 2003
Registrant Contact: IETF, SIMPLE working group, (simple@ietf.org),
Jonathan Rosenberg (jdrosen@jdrosen.net).
XML:
BEGIN
<?xml version="1.0"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML Basic 1.0//EN"
"http://www.w3.org/TR/xhtml-basic/xhtml-basic10.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="content-type"
content="text/html;charset=iso-8859-1"/>
<title>Permission Statements Namespace</title>
</head>
<body>
<h1>Namespace for Permission Statements</h1>
<h2>urn:ietf:params:xml:ns:permission-statements</h2>
<p>See <a href="[[[URL of published RFC]]]">RFCXXXX</a>.</p>
</body>
</html>
END
7.2.2 urn:ietf:params:xml:ns:compound-permissions
URI: The URI for this namespace is
urn:ietf:params:xml:ns:compound-permissions.
Registrant Contact: IETF, SIMPLE working group, (simple@ietf.org),
Jonathan Rosenberg (jdrosen@jdrosen.net).
XML:
Rosenberg Expires December 22, 2003 [Page 35]
Internet-Draft XCAP Usage for Authorization June 2003
BEGIN
<?xml version="1.0"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML Basic 1.0//EN"
"http://www.w3.org/TR/xhtml-basic/xhtml-basic10.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="content-type"
content="text/html;charset=iso-8859-1"/>
<title>Compound Permissions Namespace</title>
</head>
<body>
<h1>Namespace for Compound Permissions</h1>
<h2>urn:ietf:params:xml:ns:compound-permissions</h2>
<p>See <a href="[[[URL of published RFC]]]">RFCXXXX</a>.</p>
</body>
</html>
END
7.2.3 urn:ietf:params:xml:ns:supported-permissions
URI: The URI for this namespace is
urn:ietf:params:xml:ns:supported-permissions.
Registrant Contact: IETF, SIMPLE working group, (simple@ietf.org),
Jonathan Rosenberg (jdrosen@jdrosen.net).
XML:
BEGIN
<?xml version="1.0"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML Basic 1.0//EN"
"http://www.w3.org/TR/xhtml-basic/xhtml-basic10.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="content-type"
content="text/html;charset=iso-8859-1"/>
<title>Supported Permissions Namespace</title>
</head>
<body>
<h1>Namespace for Supported Permissions</h1>
<h2>urn:ietf:params:xml:ns:supported-permissions</h2>
<p>See <a href="[[[URL of published RFC]]]">RFCXXXX</a>.</p>
</body>
</html>
END
Rosenberg Expires December 22, 2003 [Page 36]
Internet-Draft XCAP Usage for Authorization June 2003
7.3 XML Schema Registrations
This section registers three XML schemas as per the procedures in
[11].
7.3.1 Permissions Statements
URI: please assign.
Registrant Contact: IETF, SIMPLE working group, (simple@ietf.org),
Jonathan Rosenberg (jdrosen@jdrosen.net).
The XML for this schema can be found as the sole content of
Section 4.6.
7.3.2 Compound Permissions
URI: please assign.
Registrant Contact: IETF, SIMPLE working group, (simple@ietf.org),
Jonathan Rosenberg (jdrosen@jdrosen.net).
The XML for this schema can be found as the sole content of
Section 5.5.
7.3.3 Supported Permissions
URI: please assign.
Registrant Contact: IETF, SIMPLE working group, (simple@ietf.org),
Jonathan Rosenberg (jdrosen@jdrosen.net).
The XML for this schema can be found as the sole content of
Section 6.5.
Rosenberg Expires December 22, 2003 [Page 37]
Internet-Draft XCAP Usage for Authorization June 2003
Normative References
[1] Bradner, S., "Key words for use in RFCs to Indicate Requirement
Levels", BCP 14, RFC 2119, March 1997.
[2] Rosenberg, J., "The Extensible Markup Language (XML)
Configuration Access Protocol (XCAP)",
draft-rosenberg-simple-xcap-00 (work in progress), May 2003.
[3] Bray, T., Paoli, J., Sperberg-McQueen, C. and E. Maler,
"Extensible Markup Language (XML) 1.0 (Second Edition)", W3C
REC REC-xml-20001006, October 2000.
[4] Clark, J. and S. DeRose, "XML Path Language (XPath) Version
1.0", W3C REC REC-xpath-19991116, November 1999.
[5] Moats, R., "URN Syntax", RFC 2141, May 1997.
[6] Murata, M., St. Laurent, S. and D. Kohn, "XML Media Types", RFC
3023, January 2001.
[7] Moats, R., "A URN Namespace for IETF Documents", RFC 2648,
August 1999.
[8] Franks, J., Hallam-Baker, P., Hostetler, J., Lawrence, S.,
Leach, P., Luotonen, A. and L. Stewart, "HTTP Authentication:
Basic and Digest Access Authentication", RFC 2617, June 1999.
[9] Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston, A.,
Peterson, J., Sparks, R., Handley, M. and E. Schooler, "SIP:
Session Initiation Protocol", RFC 3261, June 2002.
[10] Ramsdell, B., "S/MIME Version 3 Message Specification", RFC
2633, June 1999.
[11] Mealling, M., "The IETF XML Registry",
draft-mealling-iana-xmlns-registry-05 (work in progress), June
2003.
Rosenberg Expires December 22, 2003 [Page 38]
Internet-Draft XCAP Usage for Authorization June 2003
Informative References
[12] Day, M., Rosenberg, J. and H. Sugano, "A Model for Presence and
Instant Messaging", RFC 2778, February 2000.
[13] Rosenberg, J., "A Presence Event Package for the Session
Initiation Protocol (SIP)", draft-ietf-simple-presence-10 (work
in progress), January 2003.
[14] Fujimoto, S. and H. Sugano, "Presence Information Data Format
(PIDF)", draft-ietf-impp-cpim-pidf-08 (work in progress), May
2003.
[15] Jennings, C., Peterson, J. and M. Watson, "Private Extensions
to the Session Initiation Protocol (SIP) for Asserted Identity
within Trusted Networks", RFC 3325, November 2002.
[16] Rosenberg, J., "An Extensible Markup Language (XML)
Configuration Access Protocol (XCAP) Usage for Presence
Lists", draft-rosenberg-simple-xcap-list-usage-00 (work in
progress), May 2003.
Author's Address
Jonathan Rosenberg
dynamicsoft
600 Lanidex Plaza
Parsippany, NJ 07052
US
Phone: +1 973 952-5000
EMail: jdrosen@dynamicsoft.com
URI: http://www.jdrosen.net
Rosenberg Expires December 22, 2003 [Page 39]
Internet-Draft XCAP Usage for Authorization June 2003
Intellectual Property Statement
The IETF takes no position regarding the validity or scope of any
intellectual property or other rights that might be claimed to
pertain to the implementation or use of the technology described in
this document or the extent to which any license under such rights
might or might not be available; neither does it represent that it
has made any effort to identify any such rights. Information on the
IETF's procedures with respect to rights in standards-track and
standards-related documentation can be found in BCP-11. Copies of
claims of rights made available for publication and any assurances of
licenses to be made available, or the result of an attempt made to
obtain a general license or permission for the use of such
proprietary rights by implementors or users of this specification can
be obtained from the IETF Secretariat.
The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary
rights which may cover technology that may be required to practice
this standard. Please address the information to the IETF Executive
Director.
Full Copyright Statement
Copyright (C) The Internet Society (2003). All Rights Reserved.
This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it
or assist in its implementation may be prepared, copied, published
and distributed, in whole or in part, without restriction of any
kind, provided that the above copyright notice and this paragraph are
included on all such copies and derivative works. However, this
document itself may not be modified in any way, such as by removing
the copyright notice or references to the Internet Society or other
Internet organizations, except as needed for the purpose of
developing Internet standards in which case the procedures for
copyrights defined in the Internet Standards process must be
followed, or as required to translate it into languages other than
English.
The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assignees.
This document and the information contained herein is provided on an
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
Rosenberg Expires December 22, 2003 [Page 40]
Internet-Draft XCAP Usage for Authorization June 2003
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
Acknowledgement
Funding for the RFC Editor function is currently provided by the
Internet Society.
Rosenberg Expires December 22, 2003 [Page 41]
