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bpfink Documentation

Logs

bpfink is pushing logs to Kafka and the logging pipeline as a JSON blob. In order to make detection easier, all the FIM related logs are pushed at the warn level.

Structure of the logs:

As bpfink is trying to be smart during parsing, we are able to log a difference of state for dedicated structures. For the moment there's only 4 types of structures/logs:

• users
• access
• generic
• genericDiff

For each of those the internal structure is bit different, but the way it is logged is the same. Basically, when detecting a change bpfink will logs 3 different information:

• what has been added, under the add JSON key
• what has been deleted, under the del JSON key
• what is the current state, which as a different key depending on the consumer: users, generic, access, genericDiff.

In order to avoid complex logging logic, if an internal part of a structure has changed, this structure is logged both as add and del, the difference can be inferred by running a JSON diff on both entries, i.e:

{
	"message": "user entries",
	"level": "warn",
	"add": [{
		"user": "root",
		"passwd": "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXbar",
		"keys": []
	}],
	"del": [{
		"user": "root",
		"passwd": "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXfoo",
		"keys": []
	}],
	"users": [{
		"user": "root",
		"passwd": "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXbar",
		"keys": []
	}, {
		"user": "ncircle",
		"passwd": "",
		"keys": [
			"AAAAB3Nz.../Xyb7Bw== ncircle@scanning_device"
		]
	}]
}

In this example, the same user is logged both as a del and as an add, if we run a diff, we can see that the password has changed. In addition we also have the current state in order to validate that everything is fine.

{
	"message":"access entries",
	"level":"warn",
	"access":{
		"grant":["john"],
		"deny":["root","ALL"]
	},
	"add":{
		"grant":[],
		"deny":[]
	},
	"del":{
		"grant":["nobody"],
		"deny":[]
	},
	"processName":"sed"
}

In this example, the user nobody was removed from granted access. The current state of access is that user John has been granted. while root and ALL were

{
	"message":"generic file created",
	"level":"warn",
	"generic":{
		"current":"","next":"1a25723c4bbfb4ae20b83cbdcfc039e1a4d5f878e0c4b9f58db30478d6f8b6252403ba19d45ade5ea8e3bf65140a8a9b4995674626034f60cc7f405b"
	},
	"file":"dynamicPathFile",
	"processName":"touch",
	"user":"root"
}

In this example the file dynamicPathFile was created.

{
	"level": "warn",
	"add": {
		"Content": ["options timeout:2"]
	},
	"del": {
		"Content": []
	},
	"file": "/etc/resolv.conf",
	"processName": "bash",
	"user": "root",
	"version": "0.6.51",
	"message": "Critical Generic file modified"
}

In the above example the file /etc/resolv.conf was modified by adding an option. Instead of the hash as seen in generic consumer, the diff of the content is logged.