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

[Roberto Sassu]

On 6/21/2024 10:23 PM, Mimi Zohar wrote:
> On Fri, 2024-06-21 at 15:07 -0400, Paul Moore wrote:
>> 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.
> 
> Paul, I do see things posted on the linux-integrity mailing list pretty quickly.
> Unfortunately, something came up midday and I'm just seeing this now.  As for
> Roberto, it's probably a time zone issue.

Will review/check it first thing Monday morning.

Roberto

> The patch looks ok, but I haven't had a chance to apply or test it.  I'll look
> at it over the weekend and get back to you.
> 
> Mimi
> 
>>
>>>> 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
>