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Subject: Re: [PATCH v4 01/10] IMA: Defined an IMA hook to measure keys on key
 create or update
To:     Mimi Zohar <zohar@linux.ibm.com>, dhowells@redhat.com,
        matthewgarrett@google.com, sashal@kernel.org,
        jamorris@linux.microsoft.com, linux-integrity@vger.kernel.org,
        linux-security-module@vger.kernel.org, keyrings@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20191106190116.2578-1-nramas@linux.microsoft.com>
 <20191106190116.2578-2-nramas@linux.microsoft.com>
 <1573080189.5028.313.camel@linux.ibm.com>
From:   Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Message-ID: <c838a233-28fb-cad2-4694-18366c2643a4@linux.microsoft.com>
Date:   Wed, 6 Nov 2019 16:21:43 -0800
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On 11/6/2019 2:43 PM, Mimi Zohar wrote:

>> +void ima_post_key_create_or_update(struct key *keyring, struct key *key,
>> +				   unsigned long flags, bool create)
>> +{
>> +	if ((keyring != NULL) && (key != NULL))
>> +		return;
> 
> I would move the patch that defines the "keyring=" policy option prior
> to this one.  Include the call to process_buffer_measurement() in this
> patch.  A subsequent patch would add support to defer measuring the
> key, by calling a function named something like
> ima_queue_key_measurement().
> 
> Mimi

As I'd stated in the other response, I wanted to isolate all key related 
code in a separate C file and build it if and only if all CONFIG 
dependencies are met.

I can do the following:

=> Define the IMA hook in ima_asymmetric_keys.c instead of ima_main.c

=> In include/linux/ima.h declare the IMA hook if 
CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS is enabled.
Else, NOP it.

#ifdef CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS
extern void ima_post_key_create_or_update(struct key *keyring,
					  struct key *key,
					  unsigned long flags,
                                           bool create);
#else
static inline void ima_post_key_create_or_update(struct key *keyring,
						 struct key *key,
						 unsigned long flags,
						 bool create) {}
#endif

Would that be acceptable?

thanks,
  -lakshmi