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Bridging Worlds: Java Agent for eBPF Events Monitoring
awiskar acharya
November 14, 2025
10:06 am

eBPF (extended Berkeley Packet Filter) has revolutionized Linux kernel observability, but accessing these low-level events from Java applications has traditionally been challenging. Java Agents combined with eBPF provide a powerful solution for deep system monitoring, performance analysis, and security enforcement directly from Java applications.

The Power of eBPF and Java Integration

eBPF allows running sandboxed programs in the Linux kernel without loading kernel modules. When combined with Java Agents, this enables:

  • Real-time system monitoring from Java applications
  • Low-overhead performance tracing
  • Security event detection and response
  • Custom kernel-level instrumentation
  • Cross-platform system observability

Architecture Overview

┌─────────────────────────────────────────────────────────────┐
│                    Java Application                         │
│  ┌─────────────────────────────────────────────────────┐   │
│  │                 Java Agent                          │   │
│  │  ┌─────────────┐  ┌─────────────┐  ┌─────────────┐  │   │
│  │  │ eBPF Loader │  │ Event Proxy │  │ JNI Bridge   │  │   │
│  │  └─────────────┘  └─────────────┘  └─────────────┘  │   │
│  └─────────────────────────────────────────────────────┘   │
└───────────────────────┬─────────────────────────────────────┘
│
┌───────────────────────▼─────────────────────────────────────┐
│                    eBPF Programs in Kernel                  │
│  ┌─────────────┐  ┌─────────────┐  ┌─────────────┐         │
│  │  Tracepoints│  │  Kprobes    │  │  Perf Events│         │
│  └─────────────┘  └─────────────┘  └─────────────┘         │
└─────────────────────────────────────────────────────────────┘

Java Agent Foundation

1. Basic Agent Structure

// ebpf-agent/src/main/java/com/ebpf/agent/EBPFAgent.java
package com.ebpf.agent;
import java.lang.instrument.Instrumentation;
import java.lang.management.ManagementFactory;
import java.nio.file.*;
import java.util.concurrent.*;
public class EBPFAgent {
private static volatile Instrumentation instrumentation;
private static ScheduledExecutorService executor;
private static NativeEBPFBridge nativeBridge;
public static void premain(String args, Instrumentation inst) {
agentmain(args, inst);
}
public static void agentmain(String args, Instrumentation inst) {
instrumentation = inst;
initializeAgent(args);
}
private static void initializeAgent(String args) {
try {
System.out.println("[eBPF Agent] Initializing...");
// Initialize native bridge
nativeBridge = new NativeEBPFBridge();
// Start event processing
executor = Executors.newScheduledThreadPool(4);
startEventProcessors();
// Load eBPF programs
loadEBPFPrograms();
System.out.println("[eBPF Agent] Initialized successfully");
} catch (Exception e) {
System.err.println("[eBPF Agent] Initialization failed: " + e.getMessage());
e.printStackTrace();
}
}
}

2. MANIFEST.MF Configuration

Manifest-Version: 1.0
Premain-Class: com.ebpf.agent.EBPFAgent
Agent-Class: com.ebpf.agent.EBPFAgent
Can-Redefine-Classes: true
Can-Retransform-Classes: true
Can-Set-Native-Method-Prefix: true
Boot-Class-Path: ebpf-agent.jar

Native Integration Layer

1. JNI Bridge for eBPF Operations

// Native bridge for eBPF operations
public class NativeEBPFBridge {
private volatile long nativeContext;
static {
System.loadLibrary("ebpfjni");
}
// Native method declarations
public native long loadBPFProgram(String programPath, String programName);
public native int attachKprobe(long programFd, String functionName, boolean isReturn);
public native int attachTracepoint(long programFd, String category, String event);
public native int createPerfBuffer(long mapFd, int cpu, int pageCount);
public native void pollPerfEvents(long context, int timeoutMs);
public native void closeBPFProgram(long programFd);
// Event callback registration
public native void setEventCallback(EBPFEventCallback callback);
public void initialize() {
nativeContext = initializeNative();
}
private native long initializeNative();
public interface EBPFEventCallback {
void onEvent(int eventType, byte[] eventData, long timestamp);
}
}

2. Corresponding Native Implementation

// src/native/ebpfjni.c
#include <jni.h>
#include <stdio.h>
#include <stdlib.h>
#include <bpf/bpf.h>
#include <bpf/libbpf.h>
#include <errno.h>
#define MAX_BUFFER_SIZE 8192
static JavaVM *jvm = NULL;
static jclass callbackClass = NULL;
static jmethodID callbackMethod = NULL;
JNIEXPORT jlong JNICALL
Java_com_ebpf_agent_NativeEBPFBridge_initializeNative(JNIEnv *env, jobject obj) {
// Initialize libbpf and create native context
struct native_context *ctx = malloc(sizeof(struct native_context));
if (!ctx) {
return 0;
}
// Initialize context
ctx->ring_buffer = NULL;
ctx->objects = NULL;
ctx->callback_obj = NULL;
return (jlong)ctx;
}
JNIEXPORT jlong JNICALL
Java_com_ebpf_agent_NativeEBPFBridge_loadBPFProgram(JNIEnv *env, jobject obj, 
jstring programPath, jstring programName) {
const char *path = (*env)->GetStringUTFChars(env, programPath, NULL);
const char *name = (*env)->GetStringUTFChars(env, programName, NULL);
struct bpf_object *bpf_obj = bpf_object__open(path);
if (!bpf_obj) {
fprintf(stderr, "Failed to open BPF object: %s\n", path);
return -1;
}
int ret = bpf_object__load(bpf_obj);
if (ret) {
fprintf(stderr, "Failed to load BPF object: %d\n", ret);
bpf_object__close(bpf_obj);
return -1;
}
// Store object reference
return (jlong)bpf_obj;
}

eBPF Program Examples

1. System Call Tracing eBPF Program

// ebpf/syscall_trace.bpf.c
#include <linux/bpf.h>
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_tracing.h>
#include <linux/sched.h>
struct syscall_event {
__u32 pid;
__u32 tid;
char comm[16];
int syscall_nr;
__u64 timestamp;
};
struct {
__uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY);
__uint(key_size, sizeof(__u32));
__uint(value_size, sizeof(__u32));
} events SEC(".maps");
SEC("tracepoint/raw_syscalls/sys_enter")
int trace_syscall_enter(struct trace_event_raw_sys_enter *args) {
struct syscall_event event = {};
event.pid = bpf_get_current_pid_tgid() >> 32;
event.tid = (__u32)bpf_get_current_pid_tgid();
event.syscall_nr = args->id;
event.timestamp = bpf_ktime_get_ns();
bpf_get_current_comm(&event.comm, sizeof(event.comm));
bpf_perf_event_output(args, &events, BPF_F_CURRENT_CPU, 
&event, sizeof(event));
return 0;
}
char _license[] SEC("license") = "GPL";

2. File I/O Monitoring eBPF Program

// ebpf/file_io.bpf.c
#include <linux/bpf.h>
#include <bpf/bpf_helpers.h>
#include <linux/fs.h>
struct file_io_event {
__u32 pid;
char filename[256];
__u64 bytes;
__u64 timestamp;
int operation; // 0=read, 1=write, 2=open, 3=close
};
struct {
__uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY);
__uint(key_size, sizeof(__u32));
__uint(value_size, sizeof(__u32));
} file_events SEC(".maps");
SEC("kprobe/vfs_read")
int trace_vfs_read(struct pt_regs *ctx) {
struct file_io_event event = {};
event.pid = bpf_get_current_pid_tgid() >> 32;
event.operation = 0; // read
event.timestamp = bpf_ktime_get_ns();
bpf_perf_event_output(ctx, &file_events, BPF_F_CURRENT_CPU,
&event, sizeof(event));
return 0;
}

Event Processing in Java

1. Event Handler Framework

// Event processing framework
public class EBPFEventProcessor {
private final BlockingQueue<EBPFEvent> eventQueue;
private final Map<Integer, List<EBPFEventHandler>> handlers;
private volatile boolean running = true;
public EBPFEventProcessor(int queueSize) {
this.eventQueue = new LinkedBlockingQueue<>(queueSize);
this.handlers = new ConcurrentHashMap<>();
startConsumerThread();
}
public void registerHandler(int eventType, EBPFEventHandler handler) {
handlers.computeIfAbsent(eventType, k -> new CopyOnWriteArrayList<>())
.add(handler);
}
public void onEvent(EBPFEvent event) {
if (!eventQueue.offer(event)) {
System.err.println("Event queue full, dropping event: " + event);
}
}
private void startConsumerThread() {
Thread consumer = new Thread(() -> {
while (running || !eventQueue.isEmpty()) {
try {
EBPFEvent event = eventQueue.poll(100, TimeUnit.MILLISECONDS);
if (event != null) {
processEvent(event);
}
} catch (InterruptedException e) {
Thread.currentThread().interrupt();
break;
}
}
}, "ebpf-event-consumer");
consumer.setDaemon(true);
consumer.start();
}
private void processEvent(EBPFEvent event) {
List<EBPFEventHandler> eventHandlers = handlers.get(event.getType());
if (eventHandlers != null) {
for (EBPFEventHandler handler : eventHandlers) {
try {
handler.handleEvent(event);
} catch (Exception e) {
System.err.println("Error in event handler: " + e.getMessage());
}
}
}
}
public void shutdown() {
running = false;
}
}

2. Specific Event Handlers

// System call event handler
public class SystemCallEventHandler implements EBPFEventHandler {
private final AtomicLong syscallCount = new AtomicLong();
private final Map<Integer, AtomicLong> syscallStats = new ConcurrentHashMap<>();
@Override
public void handleEvent(EBPFEvent event) {
if (event instanceof SystemCallEvent) {
SystemCallEvent syscallEvent = (SystemCallEvent) event;
// Update statistics
syscallCount.incrementAndGet();
syscallStats.computeIfAbsent(syscallEvent.getSyscallNr(), 
k -> new AtomicLong()).incrementAndGet();
// Log suspicious syscalls
if (isSuspiciousSyscall(syscallEvent)) {
logSuspiciousActivity(syscallEvent);
}
}
}
private boolean isSuspiciousSyscall(SystemCallEvent event) {
// Detect potentially malicious syscall patterns
return event.getSyscallNr() == 56 /* clone */ && 
event.getPid() != event.getTid(); // Thread creation in different process
}
private void logSuspiciousActivity(SystemCallEvent event) {
System.out.printf("[SECURITY] Suspicious syscall: pid=%d, comm=%s, syscall=%d%n",
event.getPid(), event.getComm(), event.getSyscallNr());
}
public Map<String, Object> getStats() {
Map<String, Object> stats = new HashMap<>();
stats.put("totalSyscalls", syscallCount.get());
stats.put("syscallBreakdown", new HashMap<>(syscallStats));
return stats;
}
}
// File I/O event handler
public class FileIOEventHandler implements EBPFEventHandler {
private final Map<Integer, FileIOTrace> processTraces = new ConcurrentHashMap<>();
@Override
public void handleEvent(EBPFEvent event) {
if (event instanceof FileIOEvent) {
FileIOEvent fileEvent = (FileIOEvent) event;
// Track file operations per process
processTraces.computeIfAbsent(fileEvent.getPid(), 
k -> new FileIOTrace())
.recordOperation(fileEvent);
// Detect anomalous patterns
detectAnomalies(fileEvent);
}
}
private void detectAnomalies(FileIOEvent event) {
FileIOTrace trace = processTraces.get(event.getPid());
if (trace != null && trace.isSuspiciousActivity()) {
System.out.printf("[ANOMALY] Suspicious file activity: pid=%d, file=%s%n",
event.getPid(), event.getFilename());
}
}
}

Advanced Features

1. Dynamic eBPF Program Loading

public class DynamicBPFLoader {
private final NativeEBPFBridge nativeBridge;
private final Map<String, Long> loadedPrograms;
public DynamicBPFLoader(NativeEBPFBridge bridge) {
this.nativeBridge = bridge;
this.loadedPrograms = new ConcurrentHashMap<>();
}
public boolean loadProgram(String programName, String bpfObjectPath) {
try {
long programFd = nativeBridge.loadBPFProgram(bpfObjectPath, programName);
if (programFd > 0) {
loadedPrograms.put(programName, programFd);
System.out.println("Loaded eBPF program: " + programName);
return true;
}
} catch (Exception e) {
System.err.println("Failed to load eBPF program: " + e.getMessage());
}
return false;
}
public boolean attachKprobe(String programName, String functionName, boolean isReturn) {
Long programFd = loadedPrograms.get(programName);
if (programFd != null) {
int result = nativeBridge.attachKprobe(programFd, functionName, isReturn);
return result == 0;
}
return false;
}
public void unloadProgram(String programName) {
Long programFd = loadedPrograms.remove(programName);
if (programFd != null) {
nativeBridge.closeBPFProgram(programFd);
}
}
}

2. Performance Monitoring Integration

public class PerformanceMonitor {
private final EBPFEventProcessor eventProcessor;
private final ScheduledExecutorService scheduler;
private final Map<String, PerformanceMetric> metrics;
public PerformanceMonitor(EBPFEventProcessor processor) {
this.eventProcessor = processor;
this.scheduler = Executors.newScheduledThreadPool(1);
this.metrics = new ConcurrentHashMap<>();
initializeMetrics();
startReporting();
}
private void initializeMetrics() {
// Register handlers for performance events
eventProcessor.registerHandler(EventTypes.SYSCALL_EVENT, 
new PerformanceSyscallHandler(metrics));
eventProcessor.registerHandler(EventTypes.FILE_IO_EVENT,
new PerformanceIOHandler(metrics));
}
private void startReporting() {
scheduler.scheduleAtFixedRate(() -> {
try {
reportMetrics();
} catch (Exception e) {
System.err.println("Error reporting metrics: " + e.getMessage());
}
}, 30, 30, TimeUnit.SECONDS);
}
private void reportMetrics() {
System.out.println("=== Performance Metrics ===");
metrics.forEach((name, metric) -> {
System.out.printf("%s: %s%n", name, metric.getFormattedValue());
});
System.out.println("===========================");
}
public Map<String, Object> getMetricsSnapshot() {
return metrics.entrySet().stream()
.collect(Collectors.toMap(
Map.Entry::getKey,
e -> e.getValue().getValue()
));
}
}

Security Applications

1. Runtime Security Monitoring

public class SecurityMonitor implements EBPFEventHandler {
private final Set<Integer> monitoredPids = ConcurrentHashMap.newKeySet();
private final Pattern suspiciousPatterns = Pattern.compile(
"/proc/self|/etc/passwd|/etc/shadow|/root/");
@Override
public void handleEvent(EBPFEvent event) {
if (event instanceof FileIOEvent) {
checkFileAccess((FileIOEvent) event);
} else if (event instanceof SystemCallEvent) {
checkSystemCall((SystemCallEvent) event);
}
}
private void checkFileAccess(FileIOEvent event) {
if (suspiciousPatterns.matcher(event.getFilename()).find()) {
System.out.printf("[SECURITY ALERT] Suspicious file access: " +
"pid=%d, file=%s, operation=%d%n",
event.getPid(), event.getFilename(), event.getOperation());
// Could trigger automated response here
}
}
private void checkSystemCall(SystemCallEvent event) {
// Monitor for privilege escalation attempts
if (event.getSyscallNr() == 165 /* setuid */ || 
event.getSyscallNr() == 164 /* setgid */) {
System.out.printf("[SECURITY ALERT] Privilege change attempt: " +
"pid=%d, syscall=%d%n",
event.getPid(), event.getSyscallNr());
}
}
public void monitorProcess(int pid) {
monitoredPids.add(pid);
}
}

Usage Examples

1. Application Integration

// Main application using the eBPF agent
public class MonitoringApplication {
public static void main(String[] args) throws Exception {
// The agent would typically be loaded via -javaagent JVM argument
// For demonstration, we'll simulate its usage
EBPFEventProcessor processor = new EBPFEventProcessor(10000);
// Register various handlers
processor.registerHandler(EventTypes.SYSCALL_EVENT, new SystemCallEventHandler());
processor.registerHandler(EventTypes.FILE_IO_EVENT, new FileIOEventHandler());
processor.registerHandler(EventTypes.SYSCALL_EVENT, new SecurityMonitor());
// Start performance monitoring
PerformanceMonitor perfMonitor = new PerformanceMonitor(processor);
// Main application logic
runApplicationWorkload();
// Keep running to collect events
Thread.sleep(30000);
// Print final metrics
System.out.println("Final metrics: " + perfMonitor.getMetricsSnapshot());
}
private static void runApplicationWorkload() {
// Simulate application work that generates system events
Executors.newSingleThreadScheduledExecutor()
.scheduleAtFixedRate(() -> {
try {
// File operations
Files.createTempFile("test", ".txt");
// System calls
System.currentTimeMillis();
} catch (Exception e) {
e.printStackTrace();
}
}, 0, 1, TimeUnit.SECONDS);
}
}

2. Agent Loading

# Build the agent JAR
mvn clean package
# Run application with agent
java -javaagent:ebpf-agent.jar=config=monitoring.conf \
-jar my-application.jar
# Or attach to running JVM
jcmd <pid> load instrument ebpf-agent.jar=config=monitoring.conf

Best Practices and Considerations

  1. Performance Optimization
public class OptimizedEventProcessor {
// Use object pooling to reduce GC pressure
private final ObjectPool<EBPFEvent> eventPool;
// Batch process events for better throughput
private final List<EBPFEvent> eventBatch = new ArrayList<>(100);
// Use ring buffer for highest performance
private final RingBuffer<EBPFEvent> ringBuffer;
}
  1. Error Handling and Resilience
public class ResilientEBPFAgent {
private void safeNativeCall(Runnable operation, String operationName) {
try {
operation.run();
} catch (UnsatisfiedLinkError e) {
System.err.println("Native library not available: " + operationName);
} catch (Exception e) {
System.err.println("Operation failed: " + operationName + " - " + e.getMessage());
// Attempt recovery or fallback
}
}
}

Conclusion

The Java Agent for eBPF Events bridges the gap between high-level Java applications and low-level kernel observability, enabling:

  • Deep system introspection from Java applications
  • Real-time security monitoring and threat detection
  • Performance analysis with minimal overhead
  • Custom kernel-level instrumentation tailored to application needs
  • Cross-cutting concerns like security, performance, and debugging

This combination empowers Java developers to build more observable, secure, and performant applications by leveraging the full power of eBPF without leaving the Java ecosystem. The agent architecture provides a flexible framework that can be extended for various monitoring and security use cases while maintaining the safety and productivity of the Java platform.

Category : JAVA

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