FalcoSecurity.Plugin.Sdk

FalcoSecurity.Plugin.Sdk

Unofficial Falco plugin SDK for .NET, powered by DNNE native exports and NET6+ native memory management.

Wiki

For a full example and addition information on how this works, check out the Wiki!

NuGet packages

		desc	changelog
FalcoSecurity.Plugin.Sdk		Core Plugin SDK types	CHANGELOG.md
FalcoSecurity.Plugin.Sdk.Generators		Source generators for native exports	CHANGELOG.md
FalcoSecurity.Plugin.Sdk.Template		Project template dotnet new falcoplugin

Dummy plugin sneak-peek

[FalcoPlugin(
    Id = 999,
    Name = "dummy_plugin",
    Description = "A dummy plugin",
    Contacts = "mvenditto",
    RequiredApiVersion = "2.0.0",
    Version = "1.0.0")]
public class Plugin: PluginBase, IEventSource, IFieldExtractor {
    public string EventSourceName => "dummy_source";

    public IEnumerable<string> EventSourcesToExtract 
        => Enumerable.Empty<string>(); // only consume ourselves event-source

    public IEnumerable<OpenParam> OpenParameters => 
        => Enumerable.Empty<string>(); // no specific open-params

    public IEnumerable<ExtractionField> Fields => new List<ExtractionField> {
        new(type: "uint64",
            name: "dummy.counter",
            display: "Counter value",
            desc: "Current value of the internal counter")
    };

    public IEventSourceInstance Open(IEnumerable<OpenParam> ? openParams) {
        return new CounterInstance();
    }
    
    public void Close(IEventSourceInstance instance) {
        instance.Dispose();
    }

    public void Extract(IExtractionRequest extraction, IEventReader evt) {
        var counter = BitConverter.ToInt32(evt.Data);
        extraction.SetValue((ulong) counter);
    }
}

public class CounterInstance: PullEventSourceInstance {
    public int Counter {get; set;}

    public CounterInstance(): base(batchSize: 10, eventSize: 8) {
        Counter = 1;
    }

    protected override void PullEvent(EventSourceInstanceContext ctx, IEventWriter evt) {
        var unixNano = (ulong) DateTimeOffset.Now.ToUnixTimeSeconds() * 1000000000;

        evt.Write(BitConverter.GetBytes(Counter));

        evt.SetTimestamp(unixNano);

        if (Counter >= 50) {
            ctx.IsEof = true;
        }

        Counter += 1;
    }
}

- rule: Dummy counter rule
  desc: Dummy counter equals 42
  condition: (dummy.counter=42)
  output: dummy.counter is 42 value=%dummy.counter
  priority: DEBUG
  source: dummy_source
  tags: [dummy]

admin@someplace:~$ tree /usr/share/falco
/usr/share/falco/
└── plugins
    ├── libjson.so
    ├── libk8saudit.so
    └── dummy_plugin
        ├── plugin_native.so
        ├── FalcoSecurity.Plugin.Sdk.dll
        ├── FalcoSecurity.Plugin.Sdk.DummyPlugin.dll
        ├── Microsoft.Extensions.ObjectPool.dll
        └── FalcoSecurity.Plugin.Sdk.DummyPlugin.runtimeconfig.json
        
admin@someplace:~$ falco --enable-source dummy_source
Sat Nov  5 18:08:52 2022: Falco version: 0.33.0 (x86_64)
[...TRUNCATED...]
Sat Nov  5 18:08:52 2022: Enabled event sources: dummy_source
Sat Nov  5 18:08:52 2022: Opening event source 'dummy_source'
Sat Nov  5 18:08:52 2022: Opening capture with plugin 'dummy_plugin'
Sat Nov  5 18:08:52 2022: Closing event source 'dummy_source'
18:08:52.000000000: Debug dummy.counter is 42 value=42
Events detected: 1
Rule counts by severity:
   DEBUG: 1
Triggered rules by rule name:
   Dummy counter rule: 1

admin@someplace:~$ █

Note

This sdk is Unofficial and is not associated nor endorsed by Sysdig and falcosecurity/falco