Re: [PATCH v10 4/6] KEYS: Call the IMA hook to measure keys

[Mimi Zohar]

On Wed, 2019-12-04 at 14:41 -0800, Lakshmi Ramasubramanian wrote:
> Call the IMA hook from key_create_or_update() function to measure
> the payload when a new key is created or an existing key is updated.
> 
> This patch adds the call to the IMA hook from key_create_or_update()
> function to measure the key on key create or update.
> 
> Signed-off-by: Lakshmi Ramasubramanian <nramas@xxxxxxxxxxxxxxxxxxx>

Please Cc the key/keyring maintainers, here, immediately following
your tag.

Cc: David Howells <dhowells@xxxxxxxxxx>
Cc: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>

Reviewed-by: Mimi Zohar <zohar@xxxxxxxxxxxxx>

> ---
>  include/linux/ima.h | 14 ++++++++++++++
>  security/keys/key.c | 10 ++++++++++
>  2 files changed, 24 insertions(+)
> 
> diff --git a/include/linux/ima.h b/include/linux/ima.h
> index 6d904754d858..3b89136bc218 100644
> --- a/include/linux/ima.h
> +++ b/include/linux/ima.h
> @@ -101,6 +101,20 @@ static inline void ima_add_kexec_buffer(struct kimage *image)
>  {}
>  #endif
>  
> +#if defined(CONFIG_IMA) && defined(CONFIG_ASYMMETRIC_PUBLIC_KEY_SUBTYPE)
> +extern void ima_post_key_create_or_update(struct key *keyring,
> +					  struct key *key,
> +					  const void *payload, size_t plen,
> +					  unsigned long flags, bool create);
> +#else
> +static inline void ima_post_key_create_or_update(struct key *keyring,
> +						 struct key *key,
> +						 const void *payload,
> +						 size_t plen,
> +						 unsigned long flags,
> +						 bool create) {}
> +#endif  /* CONFIG_IMA && CONFIG_ASYMMETRIC_PUBLIC_KEY_SUBTYPE */
> +
>  #ifdef CONFIG_IMA_APPRAISE
>  extern bool is_ima_appraise_enabled(void);
>  extern void ima_inode_post_setattr(struct dentry *dentry);
> diff --git a/security/keys/key.c b/security/keys/key.c
> index 764f4c57913e..718bf7217420 100644
> --- a/security/keys/key.c
> +++ b/security/keys/key.c
> @@ -13,6 +13,7 @@
>  #include <linux/security.h>
>  #include <linux/workqueue.h>
>  #include <linux/random.h>
> +#include <linux/ima.h>
>  #include <linux/err.h>
>  #include "internal.h"
>  
> @@ -936,6 +937,9 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref,
>  		goto error_link_end;
>  	}
>  
> +	ima_post_key_create_or_update(keyring, key, payload, plen,
> +				      flags, true);
> +
>  	key_ref = make_key_ref(key, is_key_possessed(keyring_ref));
>  
>  error_link_end:
> @@ -965,6 +969,12 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref,
>  	}
>  
>  	key_ref = __key_update(key_ref, &prep);
> +
> +	if (!IS_ERR(key_ref))
> +		ima_post_key_create_or_update(keyring, key,
> +					      payload, plen,
> +					      flags, false);
> +
>  	goto error_free_prep;
>  }
>  EXPORT_SYMBOL(key_create_or_update);