Thanks for the Clarification. And I see, the use case was causing some
confusion. Regarding your question:

The part I am trying to figure out in YARA is, during conditions
> evaluations when multiple rules match and is it possible to return the rule
> with highest priority.
>
Off the top of my head? No. However, if you want that functionality, the
"meta" section is the best way to add that functionality. Have you looked
at yara-python?

Regards
Shiv

".. if at first you don't succeed, then skydiving is not for you .."

".. it's inconvenient to spell out a name which is 10+11 characters long .."


On Tue, Nov 8, 2022 at 4:00 PM Sridhar BV <[email protected]> wrote:

> Hi Shiv,
>
> Seems the example shared is causing confusion. The example added is the
> set of rules we have for our use-case and do understand there is no
> "action" or "priority" keyword in YARA. The "meta" section is something we
> plan on using as well to pass results ( For example the action value ) back
> to the downstream system.
>
> The part I am trying to figure out in YARA is, during conditions
> evaluations when multiple rules match and is it possible to return the rule
> with highest priority.
>
>
>
> Thanks,
> Sridhar BV
>
>
>
> On Tuesday, November 8, 2022 at 12:58:31 PM UTC-8 [email protected]
> wrote:
>
>> Hi Sridhar,
>>
>> Perhaps I am misunderstanding your problem statement but I believe you
>> are approaching the rule making process with the wrong capability/mental
>> model. YARA does not support 'action' keyword. YARA matches binary objects
>> based on patterns and conditions regarding how to use those patterns. What
>> you do with that match is left to the upstream/downstream subsystem that
>> uses YARA.
>>
>> P.S.: Yes you can use the "meta" section in very creative ways to meet
>> your requirements. However, I cannot recommend this solution without more
>> information.
>>
>> Regards
>> Shiv
>>
>> ".. if at first you don't succeed, then skydiving is not for you .."
>>
>> ".. it's inconvenient to spell out a name which is 10+11 characters long
>> .."
>>
>>
>> On Tue, Nov 8, 2022 at 12:46 PM Sridhar BV <[email protected]> wrote:
>>
>>> Hello Yara Users,
>>>
>>> I am exploring Yara to build a rules engine where each rule has a
>>> priority attached along with an associated action. Sharing an example list
>>> of rules below for context.
>>>
>>> Rule-A { priority: 1, conditions { ... }, action: allow }
>>> Rule-B { priority: 2, conditions { ... }, action: allow }
>>> Rule-C { priority: 3, conditions { ... }, action: deny }
>>>
>>> Input for rules evaluation can match multiple rules. Lets say in the
>>> above example both Rule-B & Rule-C are a match. Since Rule-B has higher
>>> priority ( lower priority value equals higher priority ) the result action
>>> to return is "allow".
>>>
>>> I am looking for comments / suggestions on whether it is feasible to
>>> model rule priority in Yara ( not just by mere location of where the rule
>>> appears in the yara file ) ?
>>>
>>> Thanks,
>>> Sridhar BV
>>>
>>> --
>>> You received this message because you are subscribed to the Google
>>> Groups "YARA" group.
>>> To unsubscribe from this group and stop receiving emails from it, send
>>> an email to [email protected].
>>> To view this discussion on the web visit
>>> https://groups.google.com/d/msgid/yara-project/d37ed346-16b8-4a4c-870a-38c1168206f0n%40googlegroups.com
>>> <https://groups.google.com/d/msgid/yara-project/d37ed346-16b8-4a4c-870a-38c1168206f0n%40googlegroups.com?utm_medium=email&utm_source=footer>
>>> .
>>>
>> --
> You received this message because you are subscribed to the Google Groups
> "YARA" group.
> To unsubscribe from this group and stop receiving emails from it, send an
> email to [email protected].
> To view this discussion on the web visit
> https://groups.google.com/d/msgid/yara-project/c24b4520-210f-4dd4-9df1-98f248b92f79n%40googlegroups.com
> <https://groups.google.com/d/msgid/yara-project/c24b4520-210f-4dd4-9df1-98f248b92f79n%40googlegroups.com?utm_medium=email&utm_source=footer>
> .
>

-- 
You received this message because you are subscribed to the Google Groups 
"YARA" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to [email protected].
To view this discussion on the web visit 
https://groups.google.com/d/msgid/yara-project/CAJf9chLYFFKG3B3_Ux_UnFEFh90MHBaNx_9EKuM3XR6-CCtz3A%40mail.gmail.com.

Reply via email to