Writing a detection
RunReveal detections are queries that run on a schedule. Currently, SQL is the only supported language for detections, althrough pql is planned to be supported soon (and isn't difficult to translate to valid clickhouse SQL).
Parameters
When using the explore page and creating a detection you'll notice that the generated query
has {from:DateTime} and {to:DateTime} in it. These are paramters. Parameters are a clickhouse
specific syntax that you can read more about on their docs:
Always Parameters
RunReveal passes the following parameters to each of your detections every time they run to help with windowing your data.
from- The start-time of the current data window.to- The end-time of the current data window.
By including these parameters in your detection, you can support effective windowing, without needing to worry
about lost data, delayed data, etc. It's best to include in your where clause a check that the receivedAt time
is greater than or equal to the from time, and less than the to time. By using the receivedAt time
from the RunReveal log schema, you automatically handle situations where your services generate logs that
arrive on a delay (for example, cloudtrail).
For example:
SELECT
*
FROM aws_cloudtrail_logs
WHERE
eventName='Decrypt' AND
receivedAt >= {from:DateTime} AND
receivedAt < {to:DateTime}Defining your own parameters
Parameters can also be defined as well, for useful omissions, inclusions, etc. And you'll notice several of RunReveal's pre-created detections contain parameters that can be used like this. For example, to create a detection and exclude your list of office IP addresses, you can create a SQL detection like this:
SELECT * from runreveal_logs
WHERE eventName = 'thing-that-should-only-be-done-in-office'
AND srcIP not in ({officeIPs:Array(String)})With the officeIPs parameter defined like so to include each of your office IPs.
1.2.3.4, 2.3.4.5, 4.3.2.1