Hello,

On 6/8/12 4:24 PM, patrice.bodeven@orange.com wrote:

Hello,

I try to understand the nonce count handling.

By parameter “modparam("auth", "nonce_expire", 21600)” I can define the validity of the Nonce in the time.

But I want also to define the validity of the Nonce in the number of use. For exemple, I want to limit the reuse of the nonce at 64 times (including register, Invite)

But I can see the definition of the nonce_count for all the SIP users on Kamailio and not user per user.

If I understand when I use

modparam("auth", "nonce_count", 1) # enable nonce_count support

modparam("auth", "nc_array_order", 20) # 1M in-flight nonces, using 1Mb memory

modparam("auth", "nid_pool_no", 4)

I define a memory to store the nonce values for all the SIP users.

So when User A use nonce x for REGISTER and nonce y for INVITE, nonce x is still valid !

My understanding is it correct ?

Is anyway to define a nonce validity in number of times per user ?

nid_pool_no is to define more sets of nonces, that will allow better concurrency. nonce_count is about handling nc parameter which is set by client for qop -- if you look in the rfc for www digest authentication, you may get a better picture of these parameters.

Afaik, there is no way to set the number of valid times for a nonce per user, it's only time base option. One time nonce means that the nonce is rendered invalid when used even it is still valid from time point of view (better security, avoiding reply attacks).

Cheers,
Daniel

-- 
Daniel-Constantin Mierla - http://www.asipto.com
http://twitter.com/#!/miconda - http://www.linkedin.com/in/miconda
Kamailio Advanced Training, Seattle, USA, Sep 23-26, 2012 - http://asipto.com/u/katu
Kamailio Practical Workshop, Netherlands, Sep 10-12, 2012 - http://asipto.com/u/kpw