Virtual machine related events support

Hi,

We are working on a project in which we need to get some events from audit log related to virtual machine events and filter these events per guests. Currently, the audit tools doesn't support this kind of search. However we are willing to implement the necessary features to support it and we'd like to receive some feedback from audit stakeholders on our proposal.

Most of these records are generated by libvirt, but some of them are generated by SELinux (as AVC denials). To get events generated by libvirt, we'd like to search through audit records using the both "uuid" and "vm" fields.
The following records are examples of both types of records that we intend to filter:

type=VIRT_RESOURCE msg=audit(1319602467.134:33): user pid=14103 uid=0 auid=4294967295 ses=4294967295 msg='resrc=disk reason=start vm="CentOS-Guest" uuid=41ffecd5-037e-0059-b074-ab2bf354fd0a old-disk="?" new-disk="/var/lib/libvirt/images/CentOS-Guest.img":
exe="/usr/sbin/libvirtd" (hostname=?, addr=?, terminal=? res=success)' type=AVC msg=audit(1318529059.690:801): avc: denied { read } for pid=31199 comm="qemu-kvm" name="RHEL6.img" dev=dm-0 ino=524635 scontext=system_u:system_r:svirt_t:s0:c99,c999 tcontext=system_u:object_r:svirt_image_t:s0:c390,c835 tclass=file

While "vm" field contains the domain name and it's a more user friendly identifier, it's intended to be a unique only within the scope of a single host. On the other hand, "uuid" field is intended to be a global identifier.

We'd like to create a stand-alone tool, similar to aulast, to filter this kind of events and that could be part of audit's tools. It'd be able to list VM specific events, and filter these events by UUID or VM name if needed. We are intended to support the following usage/options (any suggestions are welcome):

Usage: auvirt [ options ] [ uuid | vm-name ]

Options:

--summary(default)
Write a formatted output containing summarized information as considered time period, total number of VM specific events,
total
number of events by type (start, stop, resource change) and
total
number of AVC events.

--raw
Write records related to guests as shown in audit.log. The output may contain the following record types: VIRT_CONTROL, VIRT_RESOURCE, VIRT_MACHINE_ID and AVC.

-f file, --stdin
Same as aulast.

We intend to correlate AVC denial events to guests through the security label used by a guest in a specific period.

Another proposal would be change ausearch to support two new search options:

-uu, --uuid vm-uuid
Search for an event with the given UUID.

-vm, --vm-name vm-name
Search for an event with the given virtual machine name.

However, these fields are defined by libvirt and it may be a good idea to add to libaudit a new "audit_log_*" function to enforce a standard message format for VM related events that could be used by other virtualization tools.

Quoted 54 lines · Marcelo Cerri

Hi,

We are working on a project in which we need to get some events from audit log related to virtual machine events and filter these events per guests. Currently, the audit tools doesn't support this kind of search. However we are willing to implement the necessary features to support it and we'd like to receive some feedback from audit stakeholders on our proposal.

Most of these records are generated by libvirt, but some of them are generated by SELinux (as AVC denials). To get events generated by libvirt, we'd like to search through audit records using the both "uuid" and "vm" fields.
The following records are examples of both types of records that we intend to filter:

type=VIRT_RESOURCE msg=audit(1319602467.134:33): user pid=14103 uid=0 auid=4294967295 ses=4294967295 msg='resrc=disk reason=start vm="CentOS-Guest" uuid=41ffecd5-037e-0059-b074-ab2bf354fd0a old-disk="?" new-disk="/var/lib/libvirt/images/CentOS-Guest.img":
exe="/usr/sbin/libvirtd" (hostname=?, addr=?, terminal=? res=success)' type=AVC msg=audit(1318529059.690:801): avc: denied { read } for pid=31199 comm="qemu-kvm" name="RHEL6.img" dev=dm-0 ino=524635 scontext=system_u:system_r:svirt_t:s0:c99,c999 tcontext=system_u:object_r:svirt_image_t:s0:c390,c835 tclass=file

While "vm" field contains the domain name and it's a more user friendly identifier, it's intended to be a unique only within the scope of a single host. On the other hand, "uuid" field is intended to be a global identifier.

We'd like to create a stand-alone tool, similar to aulast, to filter this kind of events and that could be part of audit's tools. It'd be able to list VM specific events, and filter these events by UUID or VM name if needed. We are intended to support the following usage/options (any suggestions are welcome):

Usage: auvirt [ options ] [ uuid | vm-name ]

Options:

--summary(default)
Write a formatted output containing summarized information as considered time period, total number of VM specific events,
total
number of events by type (start, stop, resource change) and
total
number of AVC events.

--raw
Write records related to guests as shown in audit.log. The output may contain the following record types: VIRT_CONTROL, VIRT_RESOURCE, VIRT_MACHINE_ID and AVC.

Quoted 5 lines

-f file, --stdin
Same as aulast.

We intend to correlate AVC denial events to guests through the security label used by a guest in a specific period.

This sounds fine.

Quoted 8 lines

Another proposal would be change ausearch to support two new search options:

-uu, --uuid vm-uuid
Search for an event with the given UUID.

-vm, --vm-name vm-name
Search for an event with the given virtual machine name.

This sounds fine.

Quoted 4 lines

However, these fields are defined by libvirt and it may be a good idea to add to libaudit a new "audit_log_*" function to enforce a standard message format for VM related events that could be used by other virtualization tools.

This also sounds fine.

I was also considering making a very basic report in aureport but as you can see from aulast, sometimes a special dedicated report is better for different kinds of uses.

-Steve

I'm already coding the auvirt tool and I'd like to add command line options similar to "--start" and "--end" from ausearch.

Looking into ausearch code I found two functions (ausearch_time_end and ausearch_time_start) that already parse date and time informed and support some interesting options as "now", "today", "week-ago" and etc.

Do you think there would be a problem in use these functions in auvirt?