Re: Bug- Enforcing validation when validator is NULL

[Pierangelo Masarati <ando@sys-net.it>]

Prashant kulkarni wrote:

> When I am trying to add/edit the value to the attribute "protocol
> information" which is required in our schema I am getting the error
>
> Invalid syntax :protocol information: no validator for syntax
> 1.3.6.1.4.1.1466.115.121.1.42
>
> from the earlier mailing list I have found The problem seems to be lack of
> validations in the schema_init.c source code for attribure 'Protocol
> Information'
>
> this attribute protocolInformation is defined in core.schema
>
>  {"( 1.3.6.1.4.1.1466.115.121.1.42 DESC 'Protocol Information' )",
>   0, NULL, NULL, NULL},

This syntax has been removed from RFC 2252 when revised in RFC 4517, as 
explicitly indicated in notes 21 and 28 to Appendix B of the latter. 
This because although mentioned in RFC 2252, those syntaxes were not 
defined and thus posing interoperability problems.  I believe OpenLDAP 
should move one step forward toward RFC 451* compliance by removing 
(actually, marking as OBSOLETE) those attributes from *.schema files and 
those syntaxes from hardcoded ones.

>  including values like dnPretty ,UTF8StringValidate..etc in the code instead
> of NULL values will resolve my problem, but then that require the custom
> build and I have to do for all the attributes where validation is defined as
> NULL.

Not entirely true: you could implement a run-time module that looks up 
those syntaxes and modifies the appropriate pointers right after 
initialization.  Unless significant changes in the related slapd 
structures or API, your module would seamlessly breeze through minor and 
even major releases.

Furthermore, if those syntaxes are removed from the hardcoded ones, you 
could define them via a custom schema file using the X-SUBST feature 
(ITS#5663) recently introduced in HEAD code.  It allows to provide a 
substitute syntax for  unimplemented ones.

> I personally feel that for those attributes where validation are NULL in
> schema_init.c and other schema files, the openLDAP should not force the
> validation and give this error message, as all these attributes in which
> validation are not defined becomes unusable .
>
> In Tivoli/Sun and Microsoft Active directory LDAP validation is not enforced
> where validation is defined as NULL hence I am not getting these kind of
> error in Tivoli/Sun and Microsoft Active directory for editing of this
> attribute .
>
> So any idea how to resolve this ? there is any way to modify any of the
> config file in openldap to disable this validation for protocol information
> ?
> do I have to raise bug request for the same and is this going to be fixed in
> next openLDAP release. ?
>
> Any help and suggestions in this direction is highly appreciated.

I personally believe the absence of a validator for those syntaxes is 
the safest thing OpenLDAP can do to prevent further interoperability 
issues.  The workaround illustrated above should allow you to circumvent 
your problem without too much harm.  Of course, that's my personal 
opinion, which might differ from that of the OpenLDAP project.

p.


Ing. Pierangelo Masarati
OpenLDAP Core Team

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