add protocol field

ebpf-poc/bpf_bpfeb.go

@@ -19,8 +19,9 @@ type bpfEvent struct {
 	Uid   uint32
 	Daddr uint32
 	Dport uint16
+	Proto uint8
 	Comm  [16]uint8
-	_     [2]byte
+	_     [1]byte
 }
 
 // Names of all BPF objects in the ELF.

ebpf-poc/bpf_bpfel.go

@@ -19,8 +19,9 @@ type bpfEvent struct {
 	Uid   uint32
 	Daddr uint32
 	Dport uint16
+	Proto uint8
 	Comm  [16]uint8
-	_     [2]byte
+	_     [1]byte
 }
 
 // Names of all BPF objects in the ELF.

ebpf-poc/connect.c

@@ -10,6 +10,7 @@ struct event {
   __u32 uid;
   __u32 daddr;
   __u16 dport;
+  __u8  proto;
   __u8  comm[16]; // command
 };
 
@@ -30,6 +31,7 @@ int connect4(struct bpf_sock_addr *ctx) {
   e->uid = bpf_get_current_uid_gid();
   e->daddr = ctx->user_ip4;
   e->dport = bpf_ntohs(ctx->user_port);
+  e-> proto = ctx->protocol;
   bpf_get_current_comm(&e->comm, sizeof(e->comm));
 
   bpf_ringbuf_submit(e, 0);

ebpf-poc/main.go

@@ -2,97 +2,88 @@
 
 package main
 
-import (
-	"bytes"
-	"context"
-	"encoding/binary"
-	"errors"
-	"fmt"
-	"net"
-	"os"
-	"os/signal"
-	"syscall"
-
-	"github.com/cilium/ebpf"
-	"github.com/cilium/ebpf/link"
-	"github.com/cilium/ebpf/ringbuf"
-	"github.com/cilium/ebpf/rlimit"
-)
-
 func main() {
-	err := rlimit.RemoveMemlock()
-	if err != nil {
-		fmt.Printf("Failed to remove mem lock: %v\n", err)
-		return
-	}
+	// err := rlimit.RemoveMemlock()
+	// if err != nil {
+	// 	fmt.Printf("Failed to remove mem lock: %v\n", err)
+	// 	return
+	// }
 
-	var objs bpfObjects
-	err = loadBpfObjects(&objs, nil)
-	if err != nil {
-		fmt.Printf("Failed to load bpf objects: %v\n", err)
-		return
-	}
+	// var objs bpfObjects
+	// err = loadBpfObjects(&objs, nil)
+	// if err != nil {
+	// 	fmt.Printf("Failed to load bpf objects: %v\n", err)
+	// 	return
+	// }
 
-	defer objs.Close()
+	// defer objs.Close()
 
-	rootCgroup := "/sys/fs/cgroup"
+	// rootCgroup := "/sys/fs/cgroup"
 
-	l, err := link.AttachCgroup(link.CgroupOptions{
-		Path:    rootCgroup,
-		Attach:  ebpf.AttachCGroupInet4Connect,
-		Program: objs.Connect4,
-	})
-	if err != nil {
-		fmt.Printf("Failed to attach cgroup: %v\n", err)
-		return
-	}
-	defer l.Close()
+	// l, err := link.AttachCgroup(link.CgroupOptions{
+	// 	Path:    rootCgroup,
+	// 	Attach:  ebpf.AttachCGroupInet4Connect,
+	// 	Program: objs.Connect4,
+	// })
+	// if err != nil {
+	// 	fmt.Printf("Failed to attach cgroup: %v\n", err)
+	// 	return
+	// }
+	// defer l.Close()
 
-	rd, err := ringbuf.NewReader(objs.Events)
-	if err != nil {
-		fmt.Printf("Failed to create ringbuf reader: %v\n", err)
-		return
-	}
-	defer rd.Close()
+	// rd, err := ringbuf.NewReader(objs.Events)
+	// if err != nil {
+	// 	fmt.Printf("Failed to create ringbuf reader: %v\n", err)
+	// 	return
+	// }
+	// defer rd.Close()
 
-	ctx, stop := signal.NotifyContext(context.Background(), os.Interrupt, syscall.SIGTERM)
-	defer stop() // Cleans up resources allocated by the signal package
+	// ctx, stop := signal.NotifyContext(context.Background(), os.Interrupt, syscall.SIGTERM)
+	// defer stop() // Cleans up resources allocated by the signal package
 
-	fmt.Println("Application started. Press Ctrl+C to exit.")
+	// fmt.Println("Application started. Press Ctrl+C to exit.")
 
-	go func() {
-		<-ctx.Done()
-		fmt.Println("\nSignal received, detaching and cleaning up...")
-		rd.Close()
-	}()
+	// go func() {
+	// 	<-ctx.Done()
+	// 	fmt.Println("\nSignal received, detaching and cleaning up...")
+	// 	rd.Close()
+	// }()
 
-	var e bpfEvent
-	for {
-		rec, err := rd.Read()
-		if err != nil {
-			if errors.Is(err, ringbuf.ErrClosed) {
-				return
-			}
-			fmt.Printf("failed to read raw event: %v\n", err)
-			continue
-		}
+	// var e bpfEvent
+	// for {
+	// 	rec, err := rd.Read()
+	// 	if err != nil {
+	// 		if errors.Is(err, ringbuf.ErrClosed) {
+	// 			return
+	// 		}
+	// 		fmt.Printf("failed to read raw event: %v\n", err)
+	// 		continue
+	// 	}
 
-		err = binary.Read(bytes.NewReader(rec.RawSample), binary.LittleEndian, &e)
-		if err != nil {
-			fmt.Printf("failed to read event: %v\n", err)
-			continue
-		}
+	// 	err = binary.Read(bytes.NewReader(rec.RawSample), binary.LittleEndian, &e)
+	// 	if err != nil {
+	// 		fmt.Printf("failed to read event: %v\n", err)
+	// 		continue
+	// 	}
 
-		ip := make(net.IP, 4)
-		binary.LittleEndian.PutUint32(ip, e.Daddr)
+	// 	ip := make(net.IP, 4)
+	// 	binary.LittleEndian.PutUint32(ip, e.Daddr)
 
-		name := e.Comm[:]
-		if i := bytes.IndexByte(name, 0); i != -1 {
-			name = name[:i] // keep bytes before the first NUL
-		}
-		comm := string(name)
+	// 	name := e.Comm[:]
+	// 	if i := bytes.IndexByte(name, 0); i != -1 {
+	// 		name = name[:i] // keep bytes before the first NUL
+	// 	}
+	// 	comm := string(name)
 
-		fmt.Println()
-		fmt.Printf("PID: %v\nUID: %v\ndAddr: %v\ndPort: %v\nCommand: %v\n", e.Pid, e.Uid, ip, e.Dport, comm)
-	}
+	// 	proto := ""
+	// 	switch e.Proto {
+	// 	case syscall.IPPROTO_TCP:
+	// 		proto = "TCP"
+	// 	case syscall.IPPROTO_UDP:
+	// 		proto = "UDP"
+	// 	}
+
+	// 	fmt.Println()
+	// 	fmt.Printf("PID: %v\nUID: %v\ndAddr: %v\ndPort: %v\nProto: %v\nCommand: %v\n", e.Pid, e.Uid, ip, e.Dport, proto, comm)
+	// }
 }