Re: [ima-evm-utils PATCH v3 04/13] Update imaevm_verify_hash() definition to include "hash_algo" parameter

From: Stefan Berger <stefanb@linux.ibm.com>
To: Mimi Zohar <zohar@linux.ibm.com>, linux-integrity@vger.kernel.org
Subject: Re: [ima-evm-utils PATCH v3 04/13] Update imaevm_verify_hash() definition to include "hash_algo" parameter
Date: Tue, 9 Jan 2024 11:34:20 -0500	[thread overview]
Message-ID: <d3b43368-6c5f-4e81-8e01-e95735bb26e6@linux.ibm.com> (raw)
In-Reply-To: <20240104190558.3674008-5-zohar@linux.ibm.com>

On 1/4/24 14:05, Mimi Zohar wrote:
> Instead of relying on a global static "hash_algo" variable, which is not
> concurrency-safe, update the imaevm_verify_hash() function definition
> and callers to include a "hash_algo" parameter as a place holder.
> 
> Now with the "hash_algo" parameter, export the imaevm_verify_hash()
> definition.
> 
> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
> ---
>   src/imaevm.h    |  3 +++
>   src/libimaevm.c | 15 ++++++++-------
>   2 files changed, 11 insertions(+), 7 deletions(-)
> 
> diff --git a/src/imaevm.h b/src/imaevm.h
> index 4fd421f5cd1d..0b86d28944b3 100644
> --- a/src/imaevm.h
> +++ b/src/imaevm.h
> @@ -261,6 +261,9 @@ IMAEVM_DEPRECATED int ima_verify_signature(const char *file, unsigned char *sig,
>   					   int digestlen);
>   IMAEVM_DEPRECATED void init_public_keys(const char *keyfiles);
>   
> +int imaevm_verify_hash(struct public_key_entry *public_keys, const char *file,
> +		       const char *hash_algo, const unsigned char *hash,
> +		       int size, unsigned char *sig, int siglen);
>   int ima_verify_signature2(struct public_key_entry *public_keys, const char *file,
>   			  unsigned char *sig, int siglen,
>   			  unsigned char *digest, int digestlen);
> diff --git a/src/libimaevm.c b/src/libimaevm.c
> index 9cc83e071610..a5e9fd5080ac 100644
> --- a/src/libimaevm.c
> +++ b/src/libimaevm.c
> @@ -729,9 +729,9 @@ int imaevm_hash_algo_from_sig(unsigned char *sig)
>   		return -1;
>   }
>   
> -int imaevm_verify_hash(void *public_keys, const char *file,
> -		       const unsigned char *hash, int size,
> -		       unsigned char *sig, int siglen)
> +int imaevm_verify_hash(struct public_key_entry *public_keys, const char *file,
> +		       const char *hash_algo, const unsigned char *hash,
> +		       int size, unsigned char *sig, int siglen)

With patch 3 fixed, this will disappear.

>   {
>   	/* Get signature type from sig header */
>   	if (sig[1] == DIGSIG_VERSION_1) {
> @@ -762,7 +762,8 @@ int imaevm_verify_hash(void *public_keys, const char *file,
>   int verify_hash(const char *file, const unsigned char *hash, int size,
>   		unsigned char *sig, int siglen)
>   {
> -	return imaevm_verify_hash(g_public_keys, file, hash, size, sig, siglen);
> +	return imaevm_verify_hash(g_public_keys, file, NULL, hash, size,
> +				  sig, siglen);
>   }
>   
>   int ima_verify_signature2(struct public_key_entry *public_keys, const char *file,
> @@ -795,15 +796,15 @@ int ima_verify_signature2(struct public_key_entry *public_keys, const char *file
>   	 * measurement list, not by calculating the local file digest.
>   	 */
>   	if (digest && digestlen > 0)
> -		return imaevm_verify_hash(public_keys, file, digest, digestlen,
> -					  sig, siglen);
> +		return imaevm_verify_hash(public_keys, file, NULL, digest,
> +					  digestlen, sig, siglen);
>   
>   	hashlen = ima_calc_hash(file, hash);
>   	if (hashlen <= 1)
>   		return hashlen;
>   	assert(hashlen <= sizeof(hash));
>   
> -	return imaevm_verify_hash(public_keys, file, hash, hashlen,
> +	return imaevm_verify_hash(public_keys, file, NULL, hash, hashlen,
>   				  sig, siglen);
>   }
>   

Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>