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Subject: Re: [PATCH v3] IMA: Add audit log for failure conditions
To:     Steve Grubb <sgrubb@redhat.com>
Cc:     linux-audit@redhat.com, zohar@linux.ibm.com, paul@paul-moore.com,
        linux-integrity@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20200608215343.4491-1-nramas@linux.microsoft.com>
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 <ada45440-aefd-a4b2-2a3b-c012872e86cb@linux.microsoft.com>
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From:   Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Message-ID: <518a51b7-6c8d-f55f-c73a-b15abae8e0af@linux.microsoft.com>
Date:   Tue, 9 Jun 2020 10:00:52 -0700
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On 6/9/20 9:43 AM, Steve Grubb wrote:

>> The number in parenthesis is the error code (such as ENOMEM, EINVAL,
>> etc.) IMA uses this format for reporting TPM errors in one of the audit
>> messages (In ima_add_template_entry()). I followed the same pattern.
>>
>> Would it be better if the value for "cause" is formatted as
>>
>>      cause=hashing_error_-22
>>
>>      cause=alloc_entry_-12
> 
> Neither fit the name=value style that all other events follow. What would fit
> the style is something like this:
> 
> cause=hashing_error  errno=-22
>   
> cause=alloc_entry errno=-12
> 
> Would this be OK? Also, errno is only to illustrate. You can name it
> something else as long as there are no use case collisions with our
> dictionary of field names.
> 
> https://github.com/linux-audit/audit-documentation/blob/master/specs/fields/
> field-dictionary.csv

I am fine with this.

"errno" is currently not listed in the dictionary of audit message field 
names (Thanks for the pointer to this one Steve)

Mimi - please let me know if you have any concerns with adding the 
"result" code in "errno" field in integrity_audit_msg().

Sample message:

[    8.051937] audit: type=1804 audit(1591633422.365:8): pid=1 uid=0 
auid=4294967295 ses=4294967295 subj=system_u:system_r:init_t:s0 
op=measuring_keys cause=hashing_error errno=-22 comm="systemd" 
name=".builtin_trusted_keys" res=0

thanks,
  -lakshmi