[PATCH v2] ima: instantiate the bprm_creds_for_exec() hook

[Paul Moore]

On Dec  4, 2024 Mimi Zohar <zohar at linux.ibm.com> wrote:
> 
> Like direct file execution (e.g. ./script.sh), indirect file execution
> (e.g. sh script.sh) needs to be measured and appraised.  Instantiate
> the new security_bprm_creds_for_exec() hook to measure and verify the
> indirect file's integrity.  Unlike direct file execution, indirect file
> execution is optionally enforced by the interpreter.
> 
> Differentiate kernel and userspace enforced integrity audit messages.
> 
> Co-developed-by: Roberto Sassu <roberto.sassu at huawei.com>
> Signed-off-by: Roberto Sassu <roberto.sassu at huawei.com>
> Signed-off-by: Mimi Zohar <zohar at linux.ibm.com>
> ---
> Changelog v3:
> - Mickael: add comment ima_bprm_creds_for_exec(), minor code cleanup,
>   add Co-developed-by tag.
> 
> Changelog v2:
> - Mickael: Use same audit messages with new audit message number
> - Stefan Berger: Return boolean from is_bprm_creds_for_exec()
> 
>  include/uapi/linux/audit.h            |  1 +
>  security/integrity/ima/ima_appraise.c | 27 +++++++++++++++++++++++--
>  security/integrity/ima/ima_main.c     | 29 +++++++++++++++++++++++++++
>  3 files changed, 55 insertions(+), 2 deletions(-)
> 
> diff --git a/include/uapi/linux/audit.h b/include/uapi/linux/audit.h
> index 75e21a135483..826337905466 100644
> --- a/include/uapi/linux/audit.h
> +++ b/include/uapi/linux/audit.h
> @@ -161,6 +161,7 @@
>  #define AUDIT_INTEGRITY_RULE	    1805 /* policy rule */
>  #define AUDIT_INTEGRITY_EVM_XATTR   1806 /* New EVM-covered xattr */
>  #define AUDIT_INTEGRITY_POLICY_RULE 1807 /* IMA policy rules */
> +#define AUDIT_INTEGRITY_DATA_CHECK  1808 /* Userspace enforced data integrity */

I worry that "DATA_CHECK" is a bit vague, should we change the name so
that there is some hint of either userspace enforcement or
AT_EXECVE_CHECK?

What about AUDIT_INTEGRITY_DATA_USER?

--
paul-moore.com