tls authentication : certificate dn to directory dn mapping

[Francois Beretti <francois.beretti@enatel.com>]

hello all

I am settling up EXTERNAL authentication
I have some problems to map the dn of the users' certs to a directory dn
the dn of the certs are like this :
givenName=John+sn=Smith+cn=0123456789,ou=012345678900,l=state,o=MYORGANISATION,c=fr

the "cn" field is unique in this PKI.

I would like to map such a dn with the directory entry that have 
0123456789 (the cert's "cn" field value) as the value of one attibute, 
uniqueID for exemple.

In other words :

certificate of john smith :
cn=0123456789

map to entry :
dn: cn=John Smith, ou=people,dc=mydomain,dc=com
cn: John Smith
uniqueID: 0123456789  <==== the same value as the cn value of the cert's dn
sn: ...

I don't find how to do it with sasl-regexp


Thank you very much

François Beretti