fake: add new mode random_single_value

Author: sebix

CHANGELOG.md

@@ -28,6 +28,7 @@ Please refer to the [NEWS](NEWS.md) for a list of changes which have an affect o
 
 #### Experts
 - `intelmq.bots.experts.asn_lookup.expert`: Print URLs to stdout only in verbose mode (PR#2591 by Sebastian Wagner).
+- `intelmq.bots.experts.fake.expert`: Add new mode `random_single_value` (PR#2601 by Sebastian Wagner).
 
 #### Outputs
 

docs/user/bots.md

@@ -2684,35 +2684,56 @@ is `$portal_url + '/api/1.0/ripe/contact?cidr=%s'`.
 
 ### Fake <div id="intelmq.bots.experts.fake.expert" />
 
-Adds fake data to events. Currently supports setting the IP address and network.
+Adds fake data to events. It currently supports two operation methods:
 
-For each incoming event, the bots chooses one random IP network range from the configured data file.
-It set's the first IP address of the range as `source.ip` and the network itself as `source.network`.
-To adapt the `source.asn` field accordingly, use the [ASN Lookup Expert](#asn-lookup).
+* Setting the IP address and network
+* For any Event event field, set the value to a random item of a used-defined list (mode `random_single_value`)
+
+For a detailed description of the modes, see below.
 
 **Module:** `intelmq.bots.experts.fake.expert`
 
 **Parameters:**
 
 **`database`**
 
-(required, string) Path to a JSON file in the following format:
+(required, string) Path to a JSON file in the following format (example):
 ```
 {
     "ip_network": [
         "10.0.0.0/8",
+        "192.168.0.0/16",
         ...
-    ]
+    ],
+    "event_fields": {
+      "extra.severity": {
+        "mode": "random_single_value",
+        "values": ["critical", "high", "medium", "low", "info", "undefined"]
+      },
+      ...
+    }
 }
 ```
+Any of the two modes can be ommitted
 
 **`overwrite`**
 
 (optional, boolean) Whether to overwrite existing fields. Defaults to false.
 
+### Modes
+
+#### IP Network
+For each incoming event, the bots chooses one random IP network range (IPv4 or IPv6) from the configured data file.
+It set's the first IP address of the range as `source.ip` and the network itself as `source.network`.
+To adapt the `source.asn` field accordingly, use the [ASN Lookup Expert](#asn-lookup).
+
 For data consistency `source.network` will only be set if `source.ip` was set or overridden.
 If overwrite is false, `source.ip` was did not exist before but `source.network` existed before, `source.network` will still be overridden.
 
+#### Event fields
+##### Mode `random_single_value`
+For any possible event field, the bot chooses a random value of the values in the `values` property.
+
 ---
 
 ### Field Reducer <div id="intelmq.bots.experts.field_reducer.expert" />

intelmq/bots/experts/fake/expert.py

@@ -7,6 +7,7 @@
 from json import load as json_load
 
 from intelmq.lib.bot import ExpertBot
+from intelmq.lib.message import Event
 
 
 class FakeExpertBot(ExpertBot):
@@ -17,30 +18,58 @@ class FakeExpertBot(ExpertBot):
 
     def init(self):
         with open(self.database) as database:
-            self.networks = json_load(database)['ip_network']
+            database = json_load(database)
+        self.ip_networks = database.get('ip_network', [])
+        self.event_fields = database.get('event_fields', {})
 
     def process(self):
         event = self.receive_message()
-        network = choice(self.networks)
+        if self.ip_networks:
+            network = choice(self.ip_networks)
 
-        updated = False
-        try:
-            updated = event.add('source.ip', ip_network(network)[1], overwrite=self.overwrite)
-        except IndexError:
-            updated = event.add('source.ip', ip_network(network)[0], overwrite=self.overwrite)
-        # For consistency, only set the network if the source.ip was set or overwritten, but then always overwrite it
-        if updated:
-            event.add('source.network', network, overwrite=True)
+            updated = False
+            try:
+                updated = event.add('source.ip', ip_network(network)[1], overwrite=self.overwrite)
+            except IndexError:
+                updated = event.add('source.ip', ip_network(network)[0], overwrite=self.overwrite)
+            # For consistency, only set the network if the source.ip was set or overwritten, but then always overwrite it
+            if updated:
+                event.add('source.network', network, overwrite=True)
+
+        for fieldname, field in self.event_fields.items():
+            if field['mode'] == 'random_single_value':
+                event.add(fieldname, choice(field['values']), overwrite=self.overwrite)
+            else:
+                raise ValueError(f"Mode {field['mode']} not supported in field {fieldname}.")
 
         self.send_message(event)
         self.acknowledge_message()
 
     def check(parameters: dict):
         try:
             with open(parameters['database']) as database:
-                json_load(database)['ip_network']
+                database = json_load(database)
         except Exception as exc:
-            return [['error', exc]]
+            return [['error', f"Could not load database: {exc}"]]
+        errors = []
+        if not isinstance(database.get('ip_network', []), list):
+            errors.append(['error', 'ip_network is not of type list'])
+        if not isinstance(database.get('event_fields', {}), dict):
+            errors.append(['error', 'event_fields is not of type dict'])
+        else:
+            test_event = Event()
+            for fieldname, field in database.get('event_fields', {}).items():
+                fieldname_check = test_event._Message__is_valid_key(fieldname)
+                if not fieldname_check[0]:
+                    errors.append(['error', f"Field name {fieldname} is not valid: {fieldname_check[1]}."])
+                mode = field.get('mode')
+                if mode not in ('random_single_value', ):
+                    errors.append(['error', f"Mode {mode} not supported in field {fieldname}."])
+                if 'values' not in field:
+                    errors.append(['error', f"No values defined in field {fieldname}."])
+                elif not isinstance(field['values'], list):
+                    errors.append(['error', f"Values is not a list in field {fieldname}."])
+        return errors if errors else None
 
 
 BOT = FakeExpertBot

intelmq/tests/bots/experts/fake/severity.json

@@ -0,0 +1,8 @@
+{
+    "event_fields": {
+        "extra.severity": {
+          "mode": "random_single_value",
+          "values": ["critical", "high", "medium", "low", "info", "undefined"]
+        }
+      }
+}

intelmq/tests/bots/experts/fake/severity.json.license

@@ -0,0 +1,2 @@
+SPDX-FileCopyrightText: 2025 Institute for Common Good Technology, Sebastian Wagner
+SPDX-License-Identifier: AGPL-3.0-or-later

intelmq/tests/bots/experts/fake/test_expert.py

@@ -12,6 +12,7 @@
 from intelmq.bots.experts.fake.expert import FakeExpertBot
 
 FAKE_DB = pkg_resources.resource_filename('intelmq', 'tests/bots/experts/fake/data.json')
+SEVERITY_DB = pkg_resources.resource_filename('intelmq', 'tests/bots/experts/fake/severity.json')
 EXAMPLE_INPUT = {"__type": "Event",
                  "source.ip": "93.184.216.34",  # example.com
                  }
@@ -45,6 +46,12 @@ def test_network_exists(self):
         self.assertIn(ip_address(msg['source.ip']), ip_network("10.0.0.0/8"))
         self.assertEqual(msg['source.network'], "10.0.0.0/8")
 
+    def test_random_single_value(self):
+        self.input_message = {"__type": "Event"}
+        self.run_bot(parameters={'database': SEVERITY_DB})
+        msg = json_loads(self.get_output_queue()[0])
+        self.assertIn(msg['extra.severity'], ["critical", "high", "medium", "low", "info", "undefined"])
+
 
 if __name__ == '__main__':  # pragma: no cover
     unittest.main()