Signed-off-by: Erik Skultety <eskultet@redhat.com> Reviewed-by: Peter Krempa <pkrempa@redhat.com>
8.9 KiB
Audit log
Introduction
A number of the libvirt virtualization drivers (QEMU/KVM and LXC) include support for logging details of important operations to the host's audit subsystem. This provides administrators / auditors with a canonical historical record of changes to virtual machines' / containers' lifecycle states and their configuration. On hosts which are running the Linux audit daemon, the logs will usually end up in /var/log/audit/audit.log
Configuration
The libvirt audit integration is enabled by default on any host which has the Linux audit subsystem active, and disabled otherwise. It is possible to alter this behaviour in the /etc/libvirt/libvirtd.conf
configuration file, via the audit_level
parameter
audit_level=0
- libvirt auditing is disabled regardless of host audit subsystem enablement.audit_level=1
- libvirt auditing is enabled if the host audit subsystem is enabled, otherwise it is disabled. This is the default behaviour.audit_level=2
- libvirt auditing is enabled regardless of host audit subsystem enablement. If the host audit subsystem is disabled, then libvirtd will refuse to complete startup and exit with an error.
In addition to have formal messages sent to the audit subsystem it is possible to tell libvirt to inject messages into its own logging layer. This will result in messages ending up in the systemd journal or /var/log/libvirt/libvirtd.log
on non-systemd hosts. This is disabled by default, but can be requested by setting the audit_logging=1
configuration parameter in the same file mentioned above.
Message types
Libvirt defines three core audit message types each of which will be described below. There are a number of common fields that will be reported for all message types.
pid
Process ID of the libvirtd daemon generating the audit record.
uid
User ID of the libvirtd daemon process generating the audit record.
subj
Security context of the libvirtd daemon process generating the audit record.
msg
String containing a list of key=value pairs specific to the type of audit record being reported.
Some fields in the msg
string are common to audit records
virt
Type of virtualization driver used. One of
qemu
orlxc
vm
Host driver unique name of the guest
uuid
Globally unique identifier for the guest
exe
Path of the libvirtd daemon
hostname
Currently unused
addr
Currently unused
terminal
Currently unused
res
Result of the action, either
success
orfailed
VIRT_CONTROL
Reports change in the lifecycle state of a virtual machine. The msg
field will include the following sub-fields
op
Type of operation performed. One of
start
,stop
orinit
reason
The reason which caused the operation to happen
vm-pid
ID of the primary/leading process associated with the guest
init-pid
ID of the
init
process in a container. Only ifop=init
andvirt=lxc
pid-ns
Namespace ID of the
init
process in a container. Only ifop=init
andvirt=lxc
VIRT_MACHINE_ID
Reports the association of a security context with a guest. The msg
field will include the following sub-fields
model
The security driver type. One of
selinux
orapparmor
vm-ctx
Security context for the guest process
img-ctx
Security context for the guest disk images and other assigned host resources
VIRT_RESOURCE
Reports the usage of a host resource by a guest. The fields include will vary according to the type of device being reported. When the guest is initially booted records will be generated for all assigned resources. If any changes are made to the running guest configuration, for example hotplug devices, or adjust resources allocation, further records will be generated.
Virtual CPU
The msg
field will include the following sub-fields
reason
The reason which caused the resource to be assigned to happen
resrc
The type of resource assigned. Set to
vcpu
old-vcpu
Original vCPU count, or 0
new-vcpu
Updated vCPU count
Memory
The msg
field will include the following sub-fields
reason
The reason which caused the resource to be assigned to happen
resrc
The type of resource assigned. Set to
mem
old-mem
Original memory size in bytes, or 0
new-mem
Updated memory size in bytes
Disk
The msg
field will include the following sub-fields
reason
The reason which caused the resource to be assigned to happen
resrc
The type of resource assigned. Set to
disk
old-disk
Original host file or device path acting as the disk backing file
new-disk
Updated host file or device path acting as the disk backing file
Network interface
The msg
field will include the following sub-fields
reason
The reason which caused the resource to be assigned to happen
resrc
The type of resource assigned. Set to
net
old-net
Original MAC address of the guest network interface
new-net
Updated MAC address of the guest network interface
If there is a host network interface associated with the guest NIC then further records may be generated
reason
The reason which caused the resource to be assigned to happen
resrc
The type of resource assigned. Set to
net
net
MAC address of the host network interface
rdev
Name of the host network interface
Filesystem
The msg
field will include the following sub-fields
reason
The reason which caused the resource to be assigned to happen
resrc
The type of resource assigned. Set to
fs
old-fs
Original host directory, file or device path backing the filesystem
new-fs
Updated host directory, file or device path backing the filesystem
Host device
The msg
field will include the following sub-fields
reason
The reason which caused the resource to be assigned to happen
resrc
The type of resource assigned. Set to
hostdev
ordev
dev
The unique bus identifier of the USB, PCI or SCSI device, if
resrc=dev
disk
The path of the block device assigned to the guest, if
resrc=hostdev
chardev
The path of the character device assigned to the guest, if
resrc=hostdev
TPM
The msg
field will include the following sub-fields
reason
The reason which caused the resource to be assigned to happen
resrc
The type of resource assigned. Set to
tpm
ortpm-emulator
device
The path of the host TPM device assigned to the guest
RNG
The msg
field will include the following sub-fields
reason
The reason which caused the resource to be assigned to happen
resrc
The type of resource assigned. Set to
rng
old-rng
Original path of the host entropy source for the RNG
new-rng
Updated path of the host entropy source for the RNG
console/serial/parallel/channel
The msg
field will include the following sub-fields
reason
The reason which caused the resource to be assigned to happen
resrc
The type of resource assigned. Set to
chardev
old-chardev
Original path of the backing character device for given emulated device
new-chardev
Updated path of the backing character device for given emulated device
smartcard
The msg
field will include the following sub-fields
reason
The reason which caused the resource to be assigned to happen
resrc
The type of resource assigned. Set to
smartcard
old-smartcard
Original path of the backing character device, certificate store or "nss-smartcard-device" for host smartcard passthrough.
new-smartcard
Updated path of the backing character device, certificate store or "nss-smartcard-device" for host smartcard passthrough.
Redirected device
The msg
field will include the following sub-fields
reason
The reason which caused the resource to be assigned to happen
resrc
The type of resource assigned. Set to
redir
bus
The bus type, only
usb
alloweddevice
The device type, only
USB redir
allowed
Control group
The msg
field will include the following sub-fields
reason
The reason which caused the resource to be assigned to happen
resrc
The type of resource assigned. Set to
cgroup
cgroup
The name of the cgroup controller
Shared memory
The msg
field will include the following sub-fields
resrc
The type of resource assigned. Set to
shmem
reason
The reason which caused the resource to be assigned to happen
size
The size of the shared memory region
shmem
Name of the shared memory region
source
Path of the backing character device for given emulated device