pfSense

Overview

pfSense is a firewall software distribution based on FreeBSD.

This intake ingest filterlog from pfSense.

Warning

This format is still in beta, please use it wisely.

Benefit from SEKOIA.IO built-in rules and upgrade OpenBSD Packet Filter with the following detection capabilities out-of-the-box.

SEKOIA.IO x OpenBSD Packet Filter on ATT&CK Navigator

SEKOIA.IO Intelligence Feed

Detect threats based on indicators of compromise (IOCs) collected by SEKOIA's Threat and Detection Research team.

Effort: elementary

Event Categories

In details, the following table denotes the type of events produced by this integration.

Name	Values
Kind	`event`
Category	`network`
Type	`connection`

Event Samples

Find below few samples of events and how they are normalized by SEKOIA.IO.

test_ingest_ipv4_carp_logs.jsontest_ingest_ipv4_icmp_logs.jsontest_ingest_ipv4_tcp_logs.jsontest_ingest_ipv4_udp_logs.jsontest_ingest_ipv6_carp_logs.jsontest_ingest_ipv6_tcp_logs.jsontest_ingest_ipv6_udp_logs.jsontest_ingest_pass_logs.json

{
    "message": "183,,,41cbdd1cea144179a26efd069e1ee54f,vtnet9,match,block,out,4,0x0,,63,18292,0,DF,112,vrrp,72,1.2.3.4,5.6.7.8,3,255,13,2,0,1",
    "event": {
        "reason": "match",
        "action": "block",
        "kind": "event",
        "category": [
            "network"
        ],
        "type": [
            "denied"
        ]
    },
    "source": {
        "ip": "1.2.3.4",
        "address": "1.2.3.4"
    },
    "destination": {
        "ip": "5.6.7.8",
        "address": "5.6.7.8"
    },
    "rule": {
        "id": "183"
    },
    "openbsd": {
        "pf": {
            "event": {
                "tracker": {
                    "id": "41cbdd1cea144179a26efd069e1ee54f"
                }
            },
            "routing": {
                "class": "0x0",
                "hoplimit": 255,
                "offset": 0,
                "flags": "DF"
            },
            "carp": {
                "vhid": "13",
                "version": "2",
                "advskew": "0",
                "advbase": "1",
                "type": 3
            }
        }
    },
    "network": {
        "direction": "outbound",
        "iana_number": "112",
        "transport": "vrrp",
        "bytes": 72
    },
    "observer": {
        "egress": {
            "interface": {
                "name": "vtnet9"
            }
        }
    },
    "related": {
        "ip": [
            "1.2.3.4",
            "5.6.7.8"
        ]
    }
}

{
    "message": "70,,,6524e587872444838f901ac45cbf807c,vtnet1,match,pass,in,4,0x0,,19,36147,0,none,1,icmp,128,1.2.3.4,5.6.7.8,datalength=108",
    "event": {
        "reason": "match",
        "action": "pass",
        "kind": "event",
        "category": [
            "network"
        ],
        "type": [
            "allowed"
        ]
    },
    "source": {
        "ip": "1.2.3.4",
        "address": "1.2.3.4"
    },
    "destination": {
        "ip": "5.6.7.8",
        "address": "5.6.7.8"
    },
    "rule": {
        "id": "70"
    },
    "openbsd": {
        "pf": {
            "event": {
                "tracker": {
                    "id": "6524e587872444838f901ac45cbf807c"
                }
            },
            "routing": {
                "class": "0x0",
                "hoplimit": 19,
                "offset": 0,
                "flags": "none"
            },
            "icmp": {
                "datalength": 108
            }
        }
    },
    "network": {
        "direction": "inbound",
        "iana_number": "1",
        "transport": "icmp",
        "bytes": 128
    },
    "observer": {
        "ingress": {
            "interface": {
                "name": "vtnet1"
            }
        }
    },
    "related": {
        "ip": [
            "1.2.3.4",
            "5.6.7.8"
        ]
    }
}

{
    "message": "341,,,138b9664ed0d438b9fa1a14116606d50,vtnet9,match,pass,in,4,0x0,,63,26567,0,DF,6,tcp,60,1.2.3.4,5.6.7.8,40234,10050,0,S,3917296601,,64240,,mss",
    "event": {
        "reason": "match",
        "action": "pass",
        "kind": "event",
        "category": [
            "network"
        ],
        "type": [
            "allowed"
        ]
    },
    "source": {
        "ip": "1.2.3.4",
        "port": 40234,
        "address": "1.2.3.4"
    },
    "destination": {
        "ip": "5.6.7.8",
        "port": 10050,
        "address": "5.6.7.8"
    },
    "rule": {
        "id": "341"
    },
    "openbsd": {
        "pf": {
            "event": {
                "tracker": {
                    "id": "138b9664ed0d438b9fa1a14116606d50"
                }
            },
            "routing": {
                "class": "0x0",
                "hoplimit": 63,
                "offset": 0,
                "flags": "DF"
            },
            "transport": {
                "bytes": 0,
                "tcp_flags": "S",
                "sequence_number": 3917296601,
                "window_size": 64240
            }
        }
    },
    "network": {
        "direction": "inbound",
        "iana_number": "6",
        "transport": "tcp",
        "bytes": 60
    },
    "observer": {
        "ingress": {
            "interface": {
                "name": "vtnet9"
            }
        }
    },
    "related": {
        "ip": [
            "1.2.3.4",
            "5.6.7.8"
        ]
    }
}

{
    "message": "183,,,41cbdd1cea144179a26efd069e1ee54f,vtnet9,match,pass,in,4,0x0,,63,18292,0,DF,17,udp,72,1.2.3.4,5.6.7.8,18448,53,52",
    "event": {
        "reason": "match",
        "action": "pass",
        "kind": "event",
        "category": [
            "network"
        ],
        "type": [
            "allowed"
        ]
    },
    "source": {
        "ip": "1.2.3.4",
        "port": 18448,
        "address": "1.2.3.4"
    },
    "destination": {
        "ip": "5.6.7.8",
        "port": 53,
        "address": "5.6.7.8"
    },
    "rule": {
        "id": "183"
    },
    "openbsd": {
        "pf": {
            "event": {
                "tracker": {
                    "id": "41cbdd1cea144179a26efd069e1ee54f"
                }
            },
            "routing": {
                "class": "0x0",
                "hoplimit": 63,
                "offset": 0,
                "flags": "DF"
            },
            "transport": {
                "bytes": 52
            }
        }
    },
    "network": {
        "direction": "inbound",
        "iana_number": "17",
        "transport": "udp",
        "bytes": 72
    },
    "observer": {
        "ingress": {
            "interface": {
                "name": "vtnet9"
            }
        }
    },
    "related": {
        "ip": [
            "1.2.3.4",
            "5.6.7.8"
        ]
    }
}

{
    "message": "123,001,anchor1,label2,eth0,match,pass,in,6,,123,64,12345,0,DF,vrrp,6,80,2001:0db8:85a3:0000:0000:8a2e:0370:7334,2001:0db8:85a3:0000:0000:ac1f:0001:0023,3,64,1,2,3,4",
    "event": {
        "reason": "match",
        "action": "pass",
        "kind": "event",
        "category": [
            "network"
        ],
        "type": [
            "allowed"
        ]
    },
    "source": {
        "ip": "2001:db8:85a3::8a2e:370:7334",
        "address": "2001:db8:85a3::8a2e:370:7334"
    },
    "destination": {
        "ip": "2001:db8:85a3::ac1f:1:23",
        "address": "2001:db8:85a3::ac1f:1:23"
    },
    "rule": {
        "id": "123",
        "ruleset": "anchor1"
    },
    "openbsd": {
        "pf": {
            "rule": {
                "subrulenr": "001"
            },
            "event": {
                "tracker": {
                    "id": "label2"
                }
            },
            "routing": {
                "hoplimit": 64,
                "flow": "123"
            },
            "carp": {
                "vhid": "1",
                "version": "2",
                "advskew": "3",
                "advbase": "4",
                "type": 3
            }
        }
    },
    "network": {
        "direction": "inbound",
        "iana_number": "6",
        "transport": "vrrp",
        "bytes": 80
    },
    "observer": {
        "ingress": {
            "interface": {
                "name": "eth0"
            }
        }
    },
    "related": {
        "ip": [
            "2001:db8:85a3::8a2e:370:7334",
            "2001:db8:85a3::ac1f:1:23"
        ]
    }
}

{
    "message": "123,001,anchor1,label2,eth0,match,pass,in,6,,1234,64,tcp,6,60,2001:0db8:85a3:0000:0000:8a2e:0370:7334,2001:0db8:85a3:0000:0000:ac1f:0001:0023,12345,80,20,AP,1234,5678,8192,0,MMS=1460 NOP WS=256 SACK_PERM=1",
    "event": {
        "reason": "match",
        "action": "pass",
        "kind": "event",
        "category": [
            "network"
        ],
        "type": [
            "allowed"
        ]
    },
    "source": {
        "ip": "2001:db8:85a3::8a2e:370:7334",
        "port": 12345,
        "address": "2001:db8:85a3::8a2e:370:7334"
    },
    "destination": {
        "ip": "2001:db8:85a3::ac1f:1:23",
        "port": 80,
        "address": "2001:db8:85a3::ac1f:1:23"
    },
    "rule": {
        "id": "123",
        "ruleset": "anchor1"
    },
    "openbsd": {
        "pf": {
            "rule": {
                "subrulenr": "001"
            },
            "event": {
                "tracker": {
                    "id": "label2"
                }
            },
            "routing": {
                "hoplimit": 64,
                "flow": "1234"
            },
            "transport": {
                "bytes": 20,
                "tcp_flags": "AP",
                "sequence_number": 1234,
                "ack": "5678",
                "window_size": 8192,
                "urgency": "0"
            }
        }
    },
    "network": {
        "direction": "inbound",
        "iana_number": "6",
        "transport": "tcp",
        "bytes": 60
    },
    "observer": {
        "ingress": {
            "interface": {
                "name": "eth0"
            }
        }
    },
    "related": {
        "ip": [
            "2001:db8:85a3::8a2e:370:7334",
            "2001:db8:85a3::ac1f:1:23"
        ]
    }
}

{
    "message": "123,001,anchor1,label2,eth0,match,pass,in,6,,1234,64,udp,17,1024,2001:0db8:85a3:0000:0000:8a2e:0370:7334,2001:0db8:85a3:0000:0000:ac1f:0001:0023,12345,80,1024",
    "event": {
        "reason": "match",
        "action": "pass",
        "kind": "event",
        "category": [
            "network"
        ],
        "type": [
            "allowed"
        ]
    },
    "source": {
        "ip": "2001:db8:85a3::8a2e:370:7334",
        "port": 12345,
        "address": "2001:db8:85a3::8a2e:370:7334"
    },
    "destination": {
        "ip": "2001:db8:85a3::ac1f:1:23",
        "port": 80,
        "address": "2001:db8:85a3::ac1f:1:23"
    },
    "rule": {
        "id": "123",
        "ruleset": "anchor1"
    },
    "openbsd": {
        "pf": {
            "rule": {
                "subrulenr": "001"
            },
            "event": {
                "tracker": {
                    "id": "label2"
                }
            },
            "routing": {
                "hoplimit": 64,
                "flow": "1234"
            },
            "transport": {
                "bytes": 1024
            }
        }
    },
    "network": {
        "direction": "inbound",
        "iana_number": "17",
        "transport": "udp",
        "bytes": 1024
    },
    "observer": {
        "ingress": {
            "interface": {
                "name": "eth0"
            }
        }
    },
    "related": {
        "ip": [
            "2001:db8:85a3::8a2e:370:7334",
            "2001:db8:85a3::ac1f:1:23"
        ]
    }
}

{
    "message": "183,,,41cbdd1cea144179a26efd069e1ee54f,vtnet9,match,pass,in,4,0x0,,63,18292,0,DF,17,udp,72,1.2.3.4,5.6.7.8,18448,53,52",
    "event": {
        "reason": "match",
        "action": "pass",
        "kind": "event",
        "category": [
            "network"
        ],
        "type": [
            "allowed"
        ]
    },
    "source": {
        "ip": "1.2.3.4",
        "port": 18448,
        "address": "1.2.3.4"
    },
    "destination": {
        "ip": "5.6.7.8",
        "port": 53,
        "address": "5.6.7.8"
    },
    "rule": {
        "id": "183"
    },
    "openbsd": {
        "pf": {
            "event": {
                "tracker": {
                    "id": "41cbdd1cea144179a26efd069e1ee54f"
                }
            },
            "routing": {
                "class": "0x0",
                "hoplimit": 63,
                "offset": 0,
                "flags": "DF"
            },
            "transport": {
                "bytes": 52
            }
        }
    },
    "network": {
        "direction": "inbound",
        "iana_number": "17",
        "transport": "udp",
        "bytes": 72
    },
    "observer": {
        "ingress": {
            "interface": {
                "name": "vtnet9"
            }
        }
    },
    "related": {
        "ip": [
            "1.2.3.4",
            "5.6.7.8"
        ]
    }
}

Extracted Fields

The following table lists the fields that are extracted, normalized under the ECS format, analyzed and indexed by the parser. It should be noted that infered fields are not listed.

Name	Type	Description
`destination.ip`	`ip`	IP address of the destination.
`destination.port`	`long`	Port of the destination.
`event.action`	`keyword`	The action captured by the event.
`event.category`	`keyword`	Event category. The second categorization field in the hierarchy.
`event.kind`	`keyword`	The kind of the event. The highest categorization field in the hierarchy.
`event.reason`	`keyword`	Reason why this event happened, according to the source
`event.type`	`keyword`	Event type. The third categorization field in the hierarchy.
`network.bytes`	`long`	Total bytes transferred in both directions.
`network.direction`	`keyword`	Direction of the network traffic.
`network.iana_number`	`keyword`	IANA Protocol Number.
`network.transport`	`keyword`	Protocol Name corresponding to the field `iana_number`.
`observer.egress.interface.name`	`keyword`	Interface name
`observer.ingress.interface.name`	`keyword`	Interface name
`openbsd.pf.carp.advbase`	`keyword`
`openbsd.pf.carp.advskew`	`keyword`
`openbsd.pf.carp.type`	`number`
`openbsd.pf.carp.version`	`keyword`
`openbsd.pf.carp.vhid`	`keyword`	The identifier of the virtual host that the appliance belong to in the CARP virtual group
`openbsd.pf.event.tracker.id`	`tracker`	tracker ID
`openbsd.pf.icmp.datalength`	`long`	the length of the content of the ICMP packet
`openbsd.pf.routing.class`	`keyword`
`openbsd.pf.routing.flags`	`keyword`
`openbsd.pf.routing.flow`	`keyword`
`openbsd.pf.routing.hoplimit`	`number`
`openbsd.pf.routing.offset`	`number`
`openbsd.pf.rule.subrulenr`	`integer`	number of the subrule
`openbsd.pf.transport.ack`	`keyword`
`openbsd.pf.transport.bytes`	`number`
`openbsd.pf.transport.classification`	`keyword`
`openbsd.pf.transport.options`	`keyword`
`openbsd.pf.transport.sequence_number`	`number`
`openbsd.pf.transport.tcp_flags`	`keyword`
`openbsd.pf.transport.urgency`	`keyword`
`openbsd.pf.transport.window_size`	`number`
`rule.id`	`keyword`	Rule ID
`rule.ruleset`	`keyword`	Rule ruleset
`source.ip`	`ip`	IP address of the source.
`source.port`	`long`	Port of the source.

Configure

This setup guide will show you how to forward your Firewall logs to SEKOIA.IO by means of a syslog transport channel.

Prerequisites

Have an internal log concentrator

Enable Syslog forwarding

Follow the official guide to enable syslog forwarding from your pfSense firewall to the internal log concentrator.
Define your log concentrator as a remote syslog server and select Firewall Events as the remote syslog content.
Save your changes.

Create the intake

Go to the intake page and create a new intake from the format OpenBSD Packet Filter.

Transport to SEKOIA.IO

Please consult the Syslog Forwarding documentation to forward these logs to SEKOIA.IO.