Add packet collector implementation with an error

README.md

@@ -27,6 +27,7 @@ we are missing a real modular and open source **Web Application Firewall** that
 ### Prerequisites 
 + Go 1.22+
 + golangci-lint
++ [Npcap](https://npcap.com/) (windows)
 + make (if windows, try using chocolatey)
 + openssl (if windows, try using git bash)
 + [mockery](https://vektra.github.io/mockery/latest/installation/) 

cmd/collector/main.go

@@ -1,5 +1,31 @@
 package main
 
+import (
+	"context"
+	"golang.org/x/sys/windows"
+	"log"
+
+	"waffle/internal/worker"
+	"waffle/pkg/permission"
+)
+
 func main() {
+	if !windows.GetCurrentProcessToken().IsElevated() {
+		if err := permission.RunMeElevated(); err != nil {
+			panic(err.Error())
+		}
+	}
+
+	ctx := context.Background()
+
+	log.Println("starting collector")
+
+	collector := worker.NewCollector(worker.CollectorConfig{
+		Protocol: "tcp",
+		Port:     "8080",
+	})
 
+	if err := collector.Run(ctx); err != nil {
+		panic(err.Error())
+	}
 }

internal/worker/collector.go

@@ -0,0 +1,70 @@
+package worker
+
+import (
+	"context"
+	"fmt"
+	"log"
+
+	"github.com/google/gopacket"
+	"github.com/google/gopacket/pcap"
+)
+
+type PacketSerializer interface {
+	SerializePackets(ctx context.Context, packetsChan chan<- gopacket.Packet) error
+}
+
+type CollectorConfig struct {
+	Protocol string
+	Port     string
+}
+
+type Collector struct {
+	cfg        *CollectorConfig
+	serializer PacketSerializer
+}
+
+func NewCollector(cfg CollectorConfig) *Collector {
+	return &Collector{
+		cfg: &cfg,
+	}
+}
+
+func (c *Collector) Run(ctx context.Context) error {
+	handle, err := pcap.OpenLive("eth0", 1600, true, pcap.BlockForever)
+	if err != nil {
+		return fmt.Errorf("pcap open live: %w", err)
+	}
+
+	if err := handle.SetBPFFilter(fmt.Sprintf("%s port %s", c.cfg.Protocol, c.cfg.Port)); err != nil {
+		return fmt.Errorf("set BPFF filter: %w", err)
+	}
+
+	packetSource := gopacket.NewPacketSource(handle, handle.LinkType())
+
+	packetsChan := make(chan gopacket.Packet)
+	defer func() {
+		close(packetsChan)
+
+		log.Println("collector closed")
+	}()
+
+	go func() {
+		if err := c.serializer.SerializePackets(ctx, packetsChan); err != nil {
+			log.Println("error in serialize packets")
+		}
+	}()
+
+	for {
+		select {
+		case packet, ok := <-packetSource.Packets():
+			if !ok {
+				log.Println("error reading packet")
+			}
+
+			packetsChan <- packet
+
+		case <-ctx.Done():
+			return nil
+		}
+	}
+}

pkg/permission/windows.go

@@ -0,0 +1,30 @@
+package permission
+
+import (
+	"fmt"
+	"golang.org/x/sys/windows"
+	"os"
+	"strings"
+	"syscall"
+)
+
+func RunMeElevated() error {
+	verb := "runas"
+	exe, _ := os.Executable()
+	cwd, _ := os.Getwd()
+	args := strings.Join(os.Args[1:], " ")
+
+	verbPtr, _ := syscall.UTF16PtrFromString(verb)
+	exePtr, _ := syscall.UTF16PtrFromString(exe)
+	cwdPtr, _ := syscall.UTF16PtrFromString(cwd)
+	argPtr, _ := syscall.UTF16PtrFromString(args)
+
+	var showCmd int32 = 1 //SW_NORMAL
+
+	err := windows.ShellExecute(0, verbPtr, exePtr, argPtr, cwdPtr, showCmd)
+	if err != nil {
+		return fmt.Errorf("windows shell execute: %w", err)
+	}
+
+	return nil
+}