Re: [PATCH 8/8] ima: Differentiate auditing policy rules from "audit" actions

From: Richard Guy Briggs
Date: Wed May 30 2018 - 08:50:35 EST


On 2018-05-24 16:11, Stefan Berger wrote:
> The AUDIT_INTEGRITY_RULE is used for auditing IMA policy rules and
> the IMA "audit" policy action. This patch defines
> AUDIT_INTEGRITY_POLICY_RULE to reflect the IMA policy rules.
>
> With this change we now call integrity_audit_msg_common() to get
> common integrity auditing fields. This now produces the following
> record when parsing an IMA policy rule:
>
> type=UNKNOWN[1806] msg=audit(1527004216.690:311): action=dont_measure \
> fsmagic=0x9fa0 pid=1613 uid=0 auid=0 ses=2 \
> subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 \
> op=policy_update cause=parse_rule comm="echo" exe="/usr/bin/echo" \
> tty=tty2 res=1
>
> Signed-off-by: Stefan Berger <stefanb@xxxxxxxxxxxxxxxxxx>
> ---
> include/uapi/linux/audit.h | 3 ++-
> security/integrity/ima/ima_policy.c | 5 +++--
> 2 files changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/include/uapi/linux/audit.h b/include/uapi/linux/audit.h
> index 4e61a9e05132..776e0abd35cf 100644
> --- a/include/uapi/linux/audit.h
> +++ b/include/uapi/linux/audit.h
> @@ -146,7 +146,8 @@
> #define AUDIT_INTEGRITY_STATUS 1802 /* Integrity enable status */
> #define AUDIT_INTEGRITY_HASH 1803 /* Integrity HASH type */
> #define AUDIT_INTEGRITY_PCR 1804 /* PCR invalidation msgs */
> -#define AUDIT_INTEGRITY_RULE 1805 /* policy rule */
> +#define AUDIT_INTEGRITY_RULE 1805 /* IMA "audit" action policy msgs */
> +#define AUDIT_INTEGRITY_POLICY_RULE 1806 /* IMA policy rules */
>
> #define AUDIT_KERNEL 2000 /* Asynchronous audit record. NOT A REQUEST. */
>
> diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
> index 3aed25a7178a..a8ae47a386b4 100644
> --- a/security/integrity/ima/ima_policy.c
> +++ b/security/integrity/ima/ima_policy.c
> @@ -634,7 +634,7 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry)
> int result = 0;
>
> ab = integrity_audit_log_start(NULL, GFP_KERNEL,
> - AUDIT_INTEGRITY_RULE);
> + AUDIT_INTEGRITY_POLICY_RULE);

Is it possible to connect this record to a syscall by replacing the
first parameter (NULL) by current->context?

> entry->uid = INVALID_UID;
> entry->fowner = INVALID_UID;
> @@ -926,7 +926,8 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry)
> temp_ima_appraise |= IMA_APPRAISE_FIRMWARE;
> else if (entry->func == POLICY_CHECK)
> temp_ima_appraise |= IMA_APPRAISE_POLICY;
> - audit_log_format(ab, "res=%d", !result);
> + integrity_audit_msg_common(ab, NULL, NULL,
> + "policy_update", "parse_rule", result);
> audit_log_end(ab);
> return result;
> }

- RGB

--
Richard Guy Briggs <rgb@xxxxxxxxxx>
Sr. S/W Engineer, Kernel Security, Base Operating Systems
Remote, Ottawa, Red Hat Canada
IRC: rgb, SunRaycer
Voice: +1.647.777.2635, Internal: (81) 32635