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Other helpers

Time Helpers​

TimeNow() string​

Return RFC3339 formatted time

TimeNow()

ParseUnix(unix string) string​

ParseUnix("1672239773.3590894") -> "2022-12-28T15:02:53Z"
ParseUnix("1672239773") -> "2022-12-28T15:02:53Z"
ParseUnix("notatimestamp") -> ""

Parses unix timestamp string and returns RFC3339 formatted time

Stash Helpers​

GetFromStash(cache string, key string)​

GetFromStash retrieves the value for key in the named cache. The cache are usually populated by parser's stash section. An empty string if the key doesn't exist (or has been evicted), and error is raised if the cache doesn't exist.

Others​

IsIPV4(ip string) bool​

Returns true if it's a valid IPv4.

IsIPV4("1.2.3.4")

IsIPV4(Alert.GetValue())

IsIP(ip string) bool​

Returns true if it's a valid IP (v4 or v6).

IsIP("2001:0db8:85a3:0000:0000:8a2e:0370:7334")

IsIP("1.2.3.4")

IsIP(Alert.GetValue())

GetDecisionsCount(value string) int​

Returns the number of existing decisions in database with the same value.

GetDecisionsCount("192.168.1.1")

GetDecisionsCount(Alert.GetValue())

GetDecisionsSinceCount(value string, since string) int​

Returns the number of existing decisions in database with the same value since duration string (valid time units are "ns", "us" (or "µs"), "ms", "s", "m", "h".).

GetDecisionsCount("192.168.1.1", "7h")

GetDecisionsCount(Alert.GetValue(), "30min")

KeyExists(key string, map map[string]interface{}) bool​

Return true if the key exist in the map.

Get(arr []string, index int) string​

Returns the index'th entry of arr, or "".

Distance(lat1 string, long1 string, lat2 string, long2 string) float64​

Computes the distance in kilometers between the set of coordinates represented by lat1/long1 and lat2/long2. Designed to implement impossible travel and similar scenarios:

type: conditional
name: demo/impossible-travel
description: "test"
filter: "evt.Meta.log_type == 'fake_ok'"
groupby: evt.Meta.user
capacity: -1
condition: |
  len(queue.Queue) >= 2 
  and Distance(queue.Queue[-1].Enriched.Latitude, queue.Queue[-1].Enriched.Longitude,
  queue.Queue[-2].Enriched.Latitude, queue.Queue[-2].Enriched.Longitude) > 100
leakspeed: 3h
labels:
  type: fraud

Notes:

  • Will return 0 if either set of coordinates is nil (ie. IP couldn't be geoloc)
  • Assumes that the earth is spherical and uses the haversine formula.

Hostname() string​

Returns the hostname of the machine.

Alert specific helpers​

Alert.Remediation bool​

Is true if the alert asks for a remediation. Will be true for alerts from scenarios with remediation: true flag. Will be false for alerts from manual cscli decisions add commands (as they come with their own decision).

Alert.GetScenario() string​

Returns the name of the scenario that triggered the alert.

Alert.GetScope() string​

Returns the scope of an alert. Most common value is Ip. Country and As are generally used for more distributed attacks detection/remediation.

Alert.GetValue() string​

Returns the value of an alert. field value of a Source, most common value can be a IPv4, IPv6 or other if the Scope is different than Ip.

Alert.GetSources() []string​

Return the list of IP addresses in the alert sources.

Alert.GetEventsCount() int32​

Return the number of events in the bucket.

Event specific helpers​

Event.GetType() string​

Returns the type of an Event : overflow or log.

Event.GetMeta(key string) string​

Return the value of the Meta[key] in the Event object (Meta are filled only for events of type overflow).

Event.Time​

The event object holds a Time field that is set to the date of the event (in time-machine mode) or the time of event acquisition (in live mode). As it is a golang's time.Time object, all the time helpers are available, but only a few are showcased here.

Event.Time.Hour() int​

Returns the hour of the day of the event.

filter: "evt.Meta.log_type == '...' && (evt.Time.Hour() >= 20 || evt.Time.Hour() < 6)

Will detect if the event happened between 8pm and 6am (NWO).

Event.Time.Weekday().String() string​

Returns the day of the week as a string (Monday, Tuesday etc.).

filter: "evt.Meta.log_type == '...' && evt.Time.Weekday().String() in ['Saturday', 'Sunday']

Will detect if the event happend over the weekend (NWD).

Source specific helpers​

Source.GetValue() string​

Return the Source.Value field value of a Source.

Source.GetScope() string​

Return the Source.Scope field value of Source (ip, range ...)

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