[PATCH v39 01/42] integrity: disassociate ima_filter_rule from security_audit_rule

[Paul Moore]

On Fri, Jun 21, 2024 at 12:50 PM Paul Moore <paul at paul-moore.com> wrote:
> On Fri, Dec 15, 2023 at 5:16 PM Casey Schaufler <casey at schaufler-ca.com> wrote:
> >
> > Create real functions for the ima_filter_rule interfaces.
> > These replace #defines that obscure the reuse of audit
> > interfaces. The new functions are put in security.c because
> > they use security module registered hooks that we don't
> > want exported.
> >
> > Acked-by: Paul Moore <paul at paul-moore.com>
> > Reviewed-by: John Johansen <john.johansen at canonical.com>
> > Signed-off-by: Casey Schaufler <casey at schaufler-ca.com>
> > To: Mimi Zohar <zohar at linux.ibm.com>
> > Cc: linux-integrity at vger.kernel.org
> > ---
> >  include/linux/security.h     | 24 ++++++++++++++++++++++++
> >  security/integrity/ima/ima.h | 26 --------------------------
> >  security/security.c          | 21 +++++++++++++++++++++
> >  3 files changed, 45 insertions(+), 26 deletions(-)
>
> Mimi, Roberto, are you both okay if I merge this into the lsm/dev
> branch?  The #define approach taken with the ima_filter_rule_XXX
> macros likely contributed to the recent problem where the build
> problem caused by the new gfp_t parameter was missed during review;
> I'd like to get this into an upstream tree independent of the larger
> stacking effort as I believe it has standalone value.

... and I just realized neither Mimi or Roberto were directly CC'd on
that last email, oops.  Fixed.

> > diff --git a/include/linux/security.h b/include/linux/security.h
> > index 750130a7b9dd..4790508818ee 100644
> > --- a/include/linux/security.h
> > +++ b/include/linux/security.h
> > @@ -2009,6 +2009,30 @@ static inline void security_audit_rule_free(void *lsmrule)
> >  #endif /* CONFIG_SECURITY */
> >  #endif /* CONFIG_AUDIT */
> >
> > +#if defined(CONFIG_IMA_LSM_RULES) && defined(CONFIG_SECURITY)
> > +int ima_filter_rule_init(u32 field, u32 op, char *rulestr, void **lsmrule);
> > +int ima_filter_rule_match(u32 secid, u32 field, u32 op, void *lsmrule);
> > +void ima_filter_rule_free(void *lsmrule);
> > +
> > +#else
> > +
> > +static inline int ima_filter_rule_init(u32 field, u32 op, char *rulestr,
> > +                                          void **lsmrule)
> > +{
> > +       return 0;
> > +}
> > +
> > +static inline int ima_filter_rule_match(u32 secid, u32 field, u32 op,
> > +                                           void *lsmrule)
> > +{
> > +       return 0;
> > +}
> > +
> > +static inline void ima_filter_rule_free(void *lsmrule)
> > +{ }
> > +
> > +#endif /* defined(CONFIG_IMA_LSM_RULES) && defined(CONFIG_SECURITY) */
> > +
> >  #ifdef CONFIG_SECURITYFS
> >
> >  extern struct dentry *securityfs_create_file(const char *name, umode_t mode,
> > diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
> > index c29db699c996..560d6104de72 100644
> > --- a/security/integrity/ima/ima.h
> > +++ b/security/integrity/ima/ima.h
> > @@ -420,32 +420,6 @@ static inline void ima_free_modsig(struct modsig *modsig)
> >  }
> >  #endif /* CONFIG_IMA_APPRAISE_MODSIG */
> >
> > -/* LSM based policy rules require audit */
> > -#ifdef CONFIG_IMA_LSM_RULES
> > -
> > -#define ima_filter_rule_init security_audit_rule_init
> > -#define ima_filter_rule_free security_audit_rule_free
> > -#define ima_filter_rule_match security_audit_rule_match
> > -
> > -#else
> > -
> > -static inline int ima_filter_rule_init(u32 field, u32 op, char *rulestr,
> > -                                      void **lsmrule)
> > -{
> > -       return -EINVAL;
> > -}
> > -
> > -static inline void ima_filter_rule_free(void *lsmrule)
> > -{
> > -}
> > -
> > -static inline int ima_filter_rule_match(u32 secid, u32 field, u32 op,
> > -                                       void *lsmrule)
> > -{
> > -       return -EINVAL;
> > -}
> > -#endif /* CONFIG_IMA_LSM_RULES */
> > -
> >  #ifdef CONFIG_IMA_READ_POLICY
> >  #define        POLICY_FILE_FLAGS       (S_IWUSR | S_IRUSR)
> >  #else
> > diff --git a/security/security.c b/security/security.c
> > index d7b15ea67c3f..8e5379a76369 100644
> > --- a/security/security.c
> > +++ b/security/security.c
> > @@ -5350,6 +5350,27 @@ int security_audit_rule_match(u32 secid, u32 field, u32 op, void *lsmrule)
> >  }
> >  #endif /* CONFIG_AUDIT */
> >
> > +#ifdef CONFIG_IMA_LSM_RULES
> > +/*
> > + * The integrity subsystem uses the same hooks as
> > + * the audit subsystem.
> > + */
> > +int ima_filter_rule_init(u32 field, u32 op, char *rulestr, void **lsmrule)
> > +{
> > +       return call_int_hook(audit_rule_init, 0, field, op, rulestr, lsmrule);
> > +}
> > +
> > +void ima_filter_rule_free(void *lsmrule)
> > +{
> > +       call_void_hook(audit_rule_free, lsmrule);
> > +}
> > +
> > +int ima_filter_rule_match(u32 secid, u32 field, u32 op, void *lsmrule)
> > +{
> > +       return call_int_hook(audit_rule_match, 0, secid, field, op, lsmrule);
> > +}
> > +#endif /* CONFIG_IMA_LSM_RULES */
> > +
> >  #ifdef CONFIG_BPF_SYSCALL
> >  /**
> >   * security_bpf() - Check if the bpf syscall operation is allowed
> > --
> > 2.41.0

-- 
paul-moore.com