in_ebpf: add documentation for experimental plugin

SUMMARY.md

@@ -98,6 +98,7 @@
   * [Elasticsearch](pipeline/inputs/elasticsearch.md)
   * [Exec](pipeline/inputs/exec.md)
   * [Exec Wasi](pipeline/inputs/exec-wasi.md)
+  * [Ebpf](pipeline/inputs/ebpf.md)
   * [Fluent Bit Metrics](pipeline/inputs/fluentbit-metrics.md)
   * [Forward](pipeline/inputs/forward.md)
   * [Head](pipeline/inputs/head.md)

pipeline/inputs/ebpf.md

@@ -0,0 +1,76 @@
+# `in_ebpf` Input Plugin for Fluent Bit (Experimental)
+
+> **Note:** This plugin is experimental and may be unstable. Use it in development or testing environments only, as its features and behavior are subject to change.
+
+The `in_ebpf` input plugin is an **experimental** plugin for Fluent Bit that uses eBPF (extended Berkeley Packet Filter) to capture low-level system events. This plugin allows Fluent Bit to monitor kernel-level activities such as process executions, file accesses, memory allocations, network connections, and signal handling. It provides valuable insights into system behavior for debugging, monitoring, and security analysis.
+
+## Overview
+
+The `in_ebpf` plugin leverages eBPF to trace kernel events in real-time. By specifying trace points, users can collect targeted system-level metrics and events, which can be particularly useful for gaining visibility into operating system interactions and performance characteristics.
+
+## System Dependencies
+
+To enable `in_ebpf`, ensure the following dependencies are installed on your system:
+- **Kernel Version**: 4.18 or higher with eBPF support enabled.
+- **Required Packages**:
+  - `bpftool`: Used to manage and debug eBPF programs.
+  - `libbpf-dev`: Provides the `libbpf` library for loading and interacting with eBPF programs.
+  - **CMake** 3.13 or higher: Required for building the plugin.
+
+### Installing Dependencies on Ubuntu
+```bash
+sudo apt update
+sudo apt install libbpf-dev linux-tools-common cmake
+```
+
+## Building Fluent Bit with `in_ebpf`
+
+To enable the `in_ebpf` plugin, follow these steps to build Fluent Bit from source:
+
+1. **Clone the Fluent Bit Repository**
+```bash
+git clone https://github.com/fluent/fluent-bit.git
+cd fluent-bit
+```
+
+2. **Configure the Build with `in_ebpf`**
+
+Create a build directory and run `cmake` with the `-DFLB_IN_EBPF=On` flag to enable the `in_ebpf` plugin:
+```bash
+mkdir build
+cd build
+cmake .. -DFLB_IN_EBPF=On
+```
+
+3. **Compile the Source**
+```bash
+make
+```
+
+4. **Run Fluent Bit**
+
+Run Fluent Bit with elevated permissions (e.g., `sudo`), as loading eBPF programs requires root access or appropriate privileges:
+```bash
+sudo ./bin/fluent-bit -c path/to/your_config.conf
+```
+
+## Configuration Example
+
+Here's a basic example of how to configure the plugin:
+
+```
+[INPUT]
+    Name          ebpf
+    Trace         trace_signal
+    Trace         trace_malloc
+    Trace         trace_bind
+```
+
+The configuration above enables tracing for:
+- Signal handling events (`trace_signal`)
+- Memory allocation events (`trace_malloc`)
+- Network bind operations (`trace_bind`)
+
+You can enable multiple traces by adding multiple `Trace` directives in your configuration.
+Full list of existing traces can be seen here: [Fluent Bit eBPF Traces](https://github.com/fluent/fluent-bit/tree/master/plugins/in_ebpf/traces)
+