[OpenIMSCore-CSCF] Support of AKAv1-MD5

[Mohsen Emami-N. <me...@ya...>]

Hi dear OpenImsCore,
I am using OpenImsCore to test my IMS compliant UE which has to support AKAv1 algorithm. I have created the needed IMPI and checked Digest-AKAv1 as the only authentication scheme and also set the default as Digest-AKAv1-MD5. 

However int the S-CSCF configuration file (scscf.cfg) , I have Digest-MD5 as registration_default_algorithm. Now when my UE sends its initial registration , it specifies the algorithm parameter as 'AKAv1-MD5' in the Authorization header as expected; but when S-CSCF asks the HSS for the authentication AVP, it specifies the authentication scheme as 'Digest-MD5' irrespective of what the UE has put in the Authorization header. 

I guess I do not understand the behavior of S-CSCF in this case, why it ignores the UE Authorization header algorithm parameter. It looks like the default authentication scheme in the user IMPI record hs to match the registration_default_algorithm in the S-CSCF configuration file (scscf.cfg); if this is correct how can S-CSCF accommodate users with different authentication scheme.
best regards,
~Mohsen