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

On Wednesday, May 30, 2018 9:54:00 AM EDT Stefan Berger wrote: > On 05/29/2018 05:30 PM, Steve Grubb wrote: >> Hello, >> >> On Thursday, May 24, 2018 4:11:05 PM EDT 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 >> Since this is a new event, do you mind moving the tty field to be between >> auid= and ses= ? That is the more natural place for it. > 6/8 refactors the code so that the integrity audit records produced by > IMA follow one format in terms of ordering of the fields, with fields > like inode optional, though, and AUDIT_INTEGRITY_RULE in the end being > the only one with a different format. Do we really want to change that > order just for 1806? > > 5/8 now produces the following: > > type=INTEGRITY_PCR msg=audit(1527685075.941:502): pid=2431 \ > uid=0 auid=1000 ses=5 \ > subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 \ > op=invalid_pcr cause=open_writers comm="grep" \ > name="/var/log/audit/audit.log" dev="dm-0" ino=1962494 \ > exe="/usr/bin/grep" tty=pts0 res=1 > > Comparing the two: > > 1806: action, fsmagic, pid, uid, auid, ses, subj, op, cause, > comm, exe, tty, res > INTEGRITY_PCR: pid, uid, auid, ses, subj, op, cause, > comm, name, dev, ino, exe, tty, res OK. I guess go with it as is. It passes testing.

-Steve >> Also, it might be more natural for the op= and cause= fields to be before >> the pid= portion. This doesn't matter as much to me because those are >> not searchable fields and they are skipped right over. But moving the >> tty field is the main comment from me. > With the refactoring in 6/8 we at least have consistency among the > INTEGRITY_* records, with the only exception being AUDIT_INTEGRITY_RULE > that has its own format: > > https://elixir.bootlin.com/linux/latest/source/security/integrity/ima/ima_a > pi.c#L324 > > The other ones currently all format using integrity_audit_msg(). > >> Thanks, >> -Steve >> >>> Signed-off-by: Stefan Berger<stefanb(a)linux.vnet.ibm.com> >>> --- >>> >>> 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); >>> >>> 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; >>> >>> }