Re: [PATCH v9 2/8] powerpc/ima: add support to initialize ima policy rules

[Mimi Zohar]

On Fri, 2019-10-25 at 12:02 -0500, Nayna Jain wrote:
> On 10/24/19 12:35 PM, Lakshmi Ramasubramanian wrote:
> > On 10/23/2019 8:47 PM, Nayna Jain wrote:
> >
> >> +/*
> >> + * The "secure_rules" are enabled only on "secureboot" enabled systems.
> >> + * These rules verify the file signatures against known good values.
> >> + * The "appraise_type=imasig|modsig" option allows the known good 
> >> signature
> >> + * to be stored as an xattr or as an appended signature.
> >> + *
> >> + * To avoid duplicate signature verification as much as possible, 
> >> the IMA
> >> + * policy rule for module appraisal is added only if 
> >> CONFIG_MODULE_SIG_FORCE
> >> + * is not enabled.
> >> + */
> >> +static const char *const secure_rules[] = {
> >> +ÂÂÂ "appraise func=KEXEC_KERNEL_CHECK appraise_type=imasig|modsig",
> >> +#ifndef CONFIG_MODULE_SIG_FORCE
> >> +ÂÂÂ "appraise func=MODULE_CHECK appraise_type=imasig|modsig",
> >> +#endif
> >> +ÂÂÂ NULL
> >> +};
> >
> > Is there any way to not use conditional compilation in the above array 
> > definition? Maybe define different functions to get "secure_rules" for 
> > when CONFIG_MODULE_SIG_FORCE is defined and when it is not defined.
> 
> How will you decide which function to be called ?

You could call "is_module_sig_enforced()".

Mimi