MESSAGE authorization rules
VaclavKubart
This document follows specification of authorization documents
suggested by and defines a document format for
storing rules for authorization of instant messages.
Terms
sender
User sending the instant message represented by URI present
in From header field.
recipient
User receiving the instant message represented by AOR/To
URI.
Instant message authorization documents
Instant message authorization document is XML document formated according
to the schema defined in . It inherits the MIME
type of common policy documents defined there - application/auth-policy+xml.
All XML elements designed in this document belong to the
urn:iptel:xml:ns:im-rules
namespace.
This namespace breaks conventions mentioned in the document which was used
as a source but it will stay here due to compatibility reasons if there will be no
problems with it.
Conditions
Conditions are processed according to the specification in .
Sphere
If the "instant messaging server" (proxy) trying to resolve authorization
rules is bound together with the presence server it can take the sphere value from the
presence server as defined in , otherwise sphere
value is considered undefined in terms of common policy processing.
Actions
This document defines one action - <im-handling>. It
is defined an enumerated integer type (like sub-handling in ). Possible values are:
block (value 0)
The message should not be delivered to the user and should
be rejected with a 403 Forbidden result code. This is the dafault value of
im-handling.
allow (value 1)
The message should be delivered to the destination user.
In the future these values may change.
If there are more matching rules, the resulting action will be the maximum
of their <im-handling> values.
Transformations
Transformations are not defined at this moment. In the future there can be
for example length limitations or some flagging (like spam
) or
rate limitations.
Example
sip:jan@example.com
sip:pavel@example.com
sip:vasek@example.com
sip:ja@example.com
allow
sip:smith@example.com
block
]]>
Usage with XCAP
This document defines im-rules
as unique application usage
ID (AUID) requiered by XCAP specification.
Naming conventions
When an instant message comes to a IM/presence server (proxy) within its
domain, the server should look for document
[xcap-root]/im-rules/users/[recipient username]/im-rules.xml and process rules
in it.
There might be new versions of internet drafts and thus links to
them my be obsolete. In such case try increment version in link or find the
draft on IETF by name.
common auth
draft-ietf-geopriv-common-policy-05.txt
presence auth
draft-ietf-simple-presence-rules-03.txt - presence authorization XML based data format
and usage with XCAP