Grouping of sub attributes in seperate VSAs

[Бенджамин Томпсон]

HI Alan

Many thanks for your quick response.


> We have a device which sends individual traffic counters for several
> > different services. The dicitionary is as follows:
> >
> > VENDOR      VasExperts              43823
> >
> > BEGIN-VENDOR    VasExperts
> >
> > ...
> >
> > ATTRIBUTE   VasExperts-Acct-Traffic-Class-Name              16  string
> > ATTRIBUTE   VasExperts-Acct-Traffic-Class-Input-Octets      17
> integer64
> > ATTRIBUTE   VasExperts-Acct-Traffic-Class-Output-Octets     18
> integer64
> > ATTRIBUTE   VasExperts-Acct-Traffic-Class-Input-Packets     19
> integer64
> > ATTRIBUTE   VasExperts-Acct-Traffic-Class-Output-Packets    20
> integer64
>
>    That might work...
>
> > In the accounting packet these attribtues are grouped into individual
> VSAs
> > as follows:
>
>   If you want *real* grouping, you need to use TLVs.  i.e. one master
> attribute, and the sub-attributes within that.
>

> > Here the fact that the five attributes are gouped together in a single
> VSA
> > means that they all contain data which pertains to the same service.
>
>   That's what you mean.  But that's not how RADIUS works.  The attributes
> are all in a flat space.
>
> > When FreeRADIUS processes the packet the attribtues are as I understand
> it
> > added to one long list and I can access them individually by their index.
>
>   Yes.
>
> > However, as I understand it the ordering of RADIUS attributes is not
> > something which is normally guaranteed
>
>   RADIUS guarantees ordering of attributes which have the same number.  It
> does NOT guarantee ordering of attributes which have a different number.
>
>   This restriction applies to VSAs, soo.
>
> > and I would like to ask is whether
> > there is any way in unlang or by other means to figure out which which
> sub
> > attribtues came from the same parent attribute.
>
>   No.  But you can fix the dictionary:
>
> VENDOR      VasExperts              43823
>
> BEGIN-VENDOR    VasExperts
>
> ...
> ATTRIBUTE   VasExperts-Acct-Traffic
>  16  tlv
> ATTRIBUTE   VasExperts-Acct-Traffic-Class-Name               16.1  string
> ATTRIBUTE   VasExperts-Acct-Traffic-Class-Input-Octets      16.2
> integer64
> ATTRIBUTE   VasExperts-Acct-Traffic-Class-Output-Octets    16.3
>  integer64
> ATTRIBUTE   VasExperts-Acct-Traffic-Class-Input-Packets     16.4
> integer64
> ATTRIBUTE   VasExperts-Acct-Traffic-Class-Output-Packets   16.5  integer64
> ...
>
>   These attributes will be packed into one parent attribute:
> VasExperts-Acct-Traffic.  And ordering of THAT attribute is guaranteed.
>

I am slightly confused. At the moment the sub-attribtues are grouped into
parent attributes of type Vendor-Specific (26) and presumably the ordering
of this attribute is preserved (as the numnber 26 is the same).

As I understand it the important thing is that the ordering of the
sub-attributes is preserved after flattening.

For example I receive two VSAs:

Vendor-Specific = [VasExperts-Acct-Traffic-Class-Name = "class1" ,
VasExperts-Acct-Traffic-Class-Output-Octets = 10]
Vendor-Specific = [VasExperts-Acct-Traffic-Class-Name = "class2" ,
VasExperts-Acct-Traffic-Class-Output-Octets = 20]

Here 10 bytes of "class1" data were downloaded and 20 bytes of "class2"
data.

After flattening I would like:

VasExperts-Acct-Traffic-Class-Name = "class1"
VasExperts-Acct-Traffic-Class-Output-Octets = 10
VasExperts-Acct-Traffic-Class-Name = "class2
VasExperts-Acct-Traffic-Class-Output-Octets = 20

The following variations would also be kind of OK:

VasExperts-Acct-Traffic-Class-Name = "class1"
VasExperts-Acct-Traffic-Class-Name = "class2"
VasExperts-Acct-Traffic-Class-Output-Octets = 10
VasExperts-Acct-Traffic-Class-Output-Octets = 20

or

VasExperts-Acct-Traffic-Class-Output-Octets = 10
VasExperts-Acct-Traffic-Class-Output-Octets = 20
VasExperts-Acct-Traffic-Class-Name = "class1"
VasExperts-Acct-Traffic-Class-Name = "class2"

or

...

However any variation where the ordering of VasExperts-Acct-Traffic-Class-Name
is not the same as the ordering of VasExperts-Acct-Traffic-Class-Output-Octets
after flattening would be a problem:

VasExperts-Acct-Traffic-Class-Name = "class2"
VasExperts-Acct-Traffic-Class-Name = "class1"
VasExperts-Acct-Traffic-Class-Output-Octets = 10
VasExperts-Acct-Traffic-Class-Output-Octets = 20


But as far as I can see this can't happen so there is actually no problem
at all