Neutron Packet Logging Framework

Packet logging service is designed as a Neutron plug-in that captures network packets for relevant resources (e.g. security group or firewall group) when the registered events occur.

Packet Logging Framework

Supported loggable resource types

From Rocky release, both of security_group and firewall_group are supported as resource types in Neutron packet logging framework.

Service Configuration

To enable the logging service, follow the below steps.

  1. On Neutron controller node, add log to service_plugins setting in /etc/neutron/neutron.conf file. For example:

    service_plugins = router,metering,log
    
  2. To enable logging service for security_group in Layer 2, add log to option extensions in section [agent] in /etc/neutron/plugins/ml2/ml2_conf.ini for controller node and in /etc/neutron/plugins/ml2/openvswitch_agent.ini for compute/network nodes. For example:

    [agent]
    extensions = log
    

    Note

    Fwaas v2 log is currently only supported by openvswitch, the firewall logging driver of linuxbridge is not implemented.

  3. To enable logging service for firewall_group in Layer 3, add fwaas_v2_log to option extensions in section [AGENT] in /etc/neutron/l3_agent.ini for network nodes. For example:

    [AGENT]
    extensions = fwaas_v2,fwaas_v2_log
    
  4. On compute/network nodes, add configuration for logging service to [network_log] in /etc/neutron/plugins/ml2/openvswitch_agent.ini and in /etc/neutron/l3_agent.ini as shown bellow:

    [network_log]
    rate_limit = 100
    burst_limit = 25
    #local_output_log_base = <None>
    

    In which, rate_limit is used to configure the maximum number of packets to be logged per second (packets per second). When a high rate triggers rate_limit, logging queues packets to be logged. burst_limit is used to configure the maximum of queued packets. And logged packets can be stored anywhere by using local_output_log_base.

    Note

    • It requires at least 100 for rate_limit and at least 25 for burst_limit.

    • If rate_limit is unset, logging will log unlimited.

    • If we don’t specify local_output_log_base, logged packets will be stored in system journal like /var/log/syslog by default.

Trusted projects policy.yaml configuration

With the default /etc/neutron/policy.yaml, administrators must set up resource logging on behalf of the cloud projects.

If projects are trusted to administer their own loggable resources in their cloud, neutron’s policy file policy.yaml can be modified to allow this.

Modify /etc/neutron/policy.yaml entries as follows:

"get_loggable_resources": "rule:regular_user",
"create_log": "rule:regular_user",
"get_log": "rule:regular_user",
"get_logs": "rule:regular_user",
"update_log": "rule:regular_user",
"delete_log": "rule:regular_user",

Service workflow for Operator

  1. To check the loggable resources that are supported by framework:

    $ openstack network loggable resources list
    +-----------------+
    | Supported types |
    +-----------------+
    | security_group  |
    | firewall_group  |
    +-----------------+
    

    Note

    • In VM ports, logging for security_group in currently works with openvswitch firewall driver only. linuxbridge is under development.

    • Logging for firewall_group works on internal router ports only. VM ports would be supported in the future.

  2. Log creation:

    • Create a logging resource with an appropriate resource type

      $ openstack network log create --resource-type security_group \
        --description "Collecting all security events" \
        --event ALL Log_Created
      +-----------------+------------------------------------------------+
      | Field           | Value                                          |
      +-----------------+------------------------------------------------+
      | Description     | Collecting all security events                 |
      | Enabled         | True                                           |
      | Event           | ALL                                            |
      | ID              | 8085c3e6-0fa2-4954-b5ce-ff6207931b6d           |
      | Name            | Log_Created                                    |
      | Project         | 02568bd62b414221956f15dbe9527d16               |
      | Resource        | None                                           |
      | Target          | None                                           |
      | Type            | security_group                                 |
      | created_at      | 2017-07-05T02:56:43Z                           |
      | revision_number | 0                                              |
      | tenant_id       | 02568bd62b414221956f15dbe9527d16               |
      | updated_at      | 2017-07-05T02:56:43Z                           |
      +-----------------+------------------------------------------------+
      

    Warning

    In the case of --resource and --target are not specified from the request, these arguments will be assigned to ALL by default. Hence, there is an enormous range of log events will be created.

    • Create logging resource with a given resource (sg1 or fwg1)

      $ openstack network log create my-log --resource-type security_group --resource sg1
      $ openstack network log create my-log --resource-type firewall_group --resource fwg1
      
    • Create logging resource with a given target (portA)

      $ openstack network log create my-log --resource-type security_group --target portA
      
    • Create logging resource for only the given target (portB) and the given resource (sg1 or fwg1)

      $ openstack network log create my-log --resource-type security_group --target portB --resource sg1
      $ openstack network log create my-log --resource-type firewall_group --target portB --resource fwg1
      

    Note

    • The Enabled field is set to True by default. If enabled, logged events are written to the destination if local_output_log_base is configured or /var/log/syslog in default.

    • The Event field will be set to ALL if --event is not specified from log creation request.

  3. Enable/Disable log

    We can enable or disable logging objects at runtime. It means that it will apply to all registered ports with the logging object immediately. For example:

    $ openstack network log set --disable Log_Created
    $ openstack network log show Log_Created
     +-----------------+------------------------------------------------+
     | Field           | Value                                          |
     +-----------------+------------------------------------------------+
     | Description     | Collecting all security events                 |
     | Enabled         | False                                          |
     | Event           | ALL                                            |
     | ID              | 8085c3e6-0fa2-4954-b5ce-ff6207931b6d           |
     | Name            | Log_Created                                    |
     | Project         | 02568bd62b414221956f15dbe9527d16               |
     | Resource        | None                                           |
     | Target          | None                                           |
     | Type            | security_group                                 |
     | created_at      | 2017-07-05T02:56:43Z                           |
     | revision_number | 1                                              |
     | tenant_id       | 02568bd62b414221956f15dbe9527d16               |
     | updated_at      | 2017-07-05T03:12:01Z                           |
     +-----------------+------------------------------------------------+
    

Logged events description

Currently, packet logging framework supports to collect ACCEPT or DROP or both events related to registered resources. As mentioned above, Neutron packet logging framework offers two loggable resources through the log service plug-in: security_group and firewall_group.

The general characteristics of each event will be shown as the following:

  • Log every DROP event: Every DROP security events will be generated when an incoming or outgoing session is blocked by the security groups or firewall groups

  • Log an ACCEPT event: The ACCEPT security event will be generated only for each NEW incoming or outgoing session that is allowed by security groups or firewall groups. More details for the ACCEPT events are shown as bellow:

    • North/South ACCEPT: For a North/South session there would be a single ACCEPT event irrespective of direction.

    • East/West ACCEPT/ACCEPT: In an intra-project East/West session where the originating port allows the session and the destination port allows the session, i.e. the traffic is allowed, there would be two ACCEPT security events generated, one from the perspective of the originating port and one from the perspective of the destination port.

    • East/West ACCEPT/DROP: In an intra-project East/West session initiation where the originating port allows the session and the destination port does not allow the session there would be ACCEPT security events generated from the perspective of the originating port and DROP security events generated from the perspective of the destination port.

  1. The security events that are collected by security group should include:

    • A timestamp of the flow.

    • A status of the flow ACCEPT/DROP.

    • An indication of the originator of the flow, e.g which project or log resource generated the events.

    • An identifier of the associated instance interface (neutron port id).

    • A layer 2, 3 and 4 information (mac, address, port, protocol, etc).

    • Security event record format:

      • Logged data of an ACCEPT event would look like:

      May 5 09:05:07 action=ACCEPT project_id=736672c700cd43e1bd321aeaf940365c
      log_resource_ids=['4522efdf-8d44-4e19-b237-64cafc49469b', '42332d89-df42-4588-a2bb-3ce50829ac51']
      vm_port=e0259ade-86de-482e-a717-f58258f7173f
      ethernet(dst='fa:16:3e:ec:36:32',ethertype=2048,src='fa:16:3e:50:aa:b5'),
      ipv4(csum=62071,dst='10.0.0.4',flags=2,header_length=5,identification=36638,offset=0,
      option=None,proto=6,src='172.24.4.10',tos=0,total_length=60,ttl=63,version=4),
      tcp(ack=0,bits=2,csum=15097,dst_port=80,offset=10,option=[TCPOptionMaximumSegmentSize(kind=2,length=4,max_seg_size=1460),
      TCPOptionSACKPermitted(kind=4,length=2), TCPOptionTimestamps(kind=8,length=10,ts_ecr=0,ts_val=196418896),
      TCPOptionNoOperation(kind=1,length=1), TCPOptionWindowScale(kind=3,length=3,shift_cnt=3)],
      seq=3284890090,src_port=47825,urgent=0,window_size=14600)
      
      • Logged data of a DROP event:

      May 5 09:05:07 action=DROP project_id=736672c700cd43e1bd321aeaf940365c
      log_resource_ids=['4522efdf-8d44-4e19-b237-64cafc49469b'] vm_port=e0259ade-86de-482e-a717-f58258f7173f
      ethernet(dst='fa:16:3e:ec:36:32',ethertype=2048,src='fa:16:3e:50:aa:b5'),
      ipv4(csum=62071,dst='10.0.0.4',flags=2,header_length=5,identification=36638,offset=0,
      option=None,proto=6,src='172.24.4.10',tos=0,total_length=60,ttl=63,version=4),
      tcp(ack=0,bits=2,csum=15097,dst_port=80,offset=10,option=[TCPOptionMaximumSegmentSize(kind=2,length=4,max_seg_size=1460),
      TCPOptionSACKPermitted(kind=4,length=2), TCPOptionTimestamps(kind=8,length=10,ts_ecr=0,ts_val=196418896),
      TCPOptionNoOperation(kind=1,length=1), TCPOptionWindowScale(kind=3,length=3,shift_cnt=3)],
      seq=3284890090,src_port=47825,urgent=0,window_size=14600)
      
  2. The events that are collected by firewall group should include:

    • A timestamp of the flow.

    • A status of the flow ACCEPT/DROP.

    • The identifier of log objects that are collecting this event

    • An identifier of the associated instance interface (neutron port id).

    • A layer 2, 3 and 4 information (mac, address, port, protocol, etc).

    • Security event record format:

      • Logged data of an ACCEPT event would look like:

      Jul 26 14:46:20:
      action=ACCEPT, log_resource_ids=[u'2e030f3a-e93d-4a76-bc60-1d11c0f6561b'], port=9882c485-b808-4a34-a3fb-b537642c66b2
      pkt=ethernet(dst='fa:16:3e:8f:47:c5',ethertype=2048,src='fa:16:3e:1b:3e:67')
      ipv4(csum=47423,dst='10.10.1.16',flags=2,header_length=5,identification=27969,offset=0,option=None,proto=1,src='10.10.0.5',tos=0,total_length=84,ttl=63,version=4)
      icmp(code=0,csum=41376,data=echo(data='\xe5\xf2\xfej\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00
      \x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00
      \x00\x00\x00\x00\x00\x00\x00',id=29185,seq=0),type=8)
      
      • Logged data of a DROP event:

      Jul 26 14:51:20:
      action=DROP, log_resource_ids=[u'2e030f3a-e93d-4a76-bc60-1d11c0f6561b'], port=9882c485-b808-4a34-a3fb-b537642c66b2
      pkt=ethernet(dst='fa:16:3e:32:7d:ff',ethertype=2048,src='fa:16:3e:28:83:51')
      ipv4(csum=17518,dst='10.10.0.5',flags=2,header_length=5,identification=57874,offset=0,option=None,proto=1,src='10.10.1.16',tos=0,total_length=84,ttl=63,version=4)
      icmp(code=0,csum=23772,data=echo(data='\x8a\xa0\xac|\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00
      \x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00
      \x00\x00\x00\x00\x00\x00\x00',id=25601,seq=5),type=8)
      

Note

No other extraneous events are generated within the security event logs, e.g. no debugging data, etc.