Revert "Merge pull request #132 from eddc005/feat-pcap"

This reverts commit c453020349, reversing
changes made to 5723490a6c.

.github/workflows/check.yaml

@@ -23,9 +23,6 @@ jobs:
         with:
           go-version: 'stable'
 
-      - name: Install pcap
-        run: sudo apt install -y libpcap-dev
-
       - run: go vet ./...
 
       - name: staticcheck
@@ -47,7 +44,4 @@ jobs:
         with:
           go-version: 'stable'
 
-      - name: Install pcap
-        run: sudo apt install -y libpcap-dev
-
       - run: go test ./...

.github/workflows/release.yaml

@@ -24,9 +24,6 @@ jobs:
         with:
           go-version: "1.22"
 
-      - name: Install pcap
-        run: sudo apt install -y libpcap-dev
-
       - name: Build
         env:
           GOOS: ${{ matrix.goos }}

cmd/root.go

@@ -43,7 +43,6 @@ var logger *zap.Logger
 // Flags
 var (
 	cfgFile   string
-	pcapFile  string
 	logLevel  string
 	logFormat string
 )
@@ -119,7 +118,6 @@ func init() {
 
 func initFlags() {
 	rootCmd.PersistentFlags().StringVarP(&cfgFile, "config", "c", "", "config file")
-	rootCmd.PersistentFlags().StringVarP(&pcapFile, "pcap", "p", "", "pcap file (optional)")
 	rootCmd.PersistentFlags().StringVarP(&logLevel, "log-level", "l", envOrDefaultString(appLogLevelEnv, "info"), "log level")
 	rootCmd.PersistentFlags().StringVarP(&logFormat, "log-format", "f", envOrDefaultString(appLogFormatEnv, "console"), "log format")
 }
@@ -169,7 +167,6 @@ type cliConfig struct {
 	IO      cliConfigIO      `mapstructure:"io"`
 	Workers cliConfigWorkers `mapstructure:"workers"`
 	Ruleset cliConfigRuleset `mapstructure:"ruleset"`
-	Replay  cliConfigReplay  `mapstructure:"replay"`
 }
 
 type cliConfigIO struct {
@@ -180,10 +177,6 @@ type cliConfigIO struct {
 	RST         bool   `mapstructure:"rst"`
 }
 
-type cliConfigReplay struct {
-	Realtime bool `mapstructure:"realtime"`
-}
-
 type cliConfigWorkers struct {
 	Count                      int           `mapstructure:"count"`
 	QueueSize                  int           `mapstructure:"queueSize"`
@@ -204,30 +197,17 @@ func (c *cliConfig) fillLogger(config *engine.Config) error {
 }
 
 func (c *cliConfig) fillIO(config *engine.Config) error {
-	var ioImpl io.PacketIO
-	var err error
-	if pcapFile != "" {
-		// Setup IO for pcap file replay
-		logger.Info("replaying from pcap file", zap.String("pcap file", pcapFile))
-		ioImpl, err = io.NewPcapPacketIO(io.PcapPacketIOConfig{
-			PcapFile: pcapFile,
-			Realtime: c.Replay.Realtime,
-		})
-	} else {
-		// Setup IO for nfqueue
-		ioImpl, err = io.NewNFQueuePacketIO(io.NFQueuePacketIOConfig{
-			QueueSize:   c.IO.QueueSize,
-			ReadBuffer:  c.IO.ReadBuffer,
-			WriteBuffer: c.IO.WriteBuffer,
-			Local:       c.IO.Local,
-			RST:         c.IO.RST,
-		})
-	}
-
+	nfio, err := io.NewNFQueuePacketIO(io.NFQueuePacketIOConfig{
+		QueueSize:   c.IO.QueueSize,
+		ReadBuffer:  c.IO.ReadBuffer,
+		WriteBuffer: c.IO.WriteBuffer,
+		Local:       c.IO.Local,
+		RST:         c.IO.RST,
+	})
 	if err != nil {
 		return configError{Field: "io", Err: err}
 	}
-	config.IO = ioImpl
+	config.IO = nfio
 	return nil
 }
 

engine/engine.go

@@ -58,17 +58,12 @@ func (e *engine) UpdateRuleset(r ruleset.Ruleset) error {
 }
 
 func (e *engine) Run(ctx context.Context) error {
-	workerCtx, workerCancel := context.WithCancel(ctx)
-	defer workerCancel() // Stop workers
-
-	// Register IO shutdown
 	ioCtx, ioCancel := context.WithCancel(ctx)
-	e.io.SetCancelFunc(ioCancel)
-	defer ioCancel() // Stop IO
+	defer ioCancel() // Stop workers & IO
 
 	// Start workers
 	for _, w := range e.workers {
-		go w.Run(workerCtx)
+		go w.Run(ioCtx)
 	}
 
 	// Register IO callback
@@ -90,8 +85,6 @@ func (e *engine) Run(ctx context.Context) error {
 		return err
 	case <-ctx.Done():
 		return nil
-	case <-ioCtx.Done():
-		return nil
 	}
 }
 

io/interface.go

@@ -48,9 +48,6 @@ type PacketIO interface {
 	ProtectedDialContext(ctx context.Context, network, address string) (net.Conn, error)
 	// Close closes the packet IO.
 	Close() error
-	// SetCancelFunc gives packet IO access to context cancel function, enabling it to
-	// trigger a shutdown
-	SetCancelFunc(cancelFunc context.CancelFunc) error
 }
 
 type ErrInvalidPacket struct {

io/nfqueue.go

@@ -281,11 +281,6 @@ func (n *nfqueuePacketIO) Close() error {
 	return n.n.Close()
 }
 
-// nfqueue IO does not issue shutdown
-func (n *nfqueuePacketIO) SetCancelFunc(cancelFunc context.CancelFunc) error {
-	return nil
-}
-
 func (n *nfqueuePacketIO) setupNft(local, rst, remove bool) error {
 	rules, err := generateNftRules(local, rst)
 	if err != nil {

io/pcap.go

@@ -1,130 +0,0 @@
-package io
-
-import (
-	"context"
-	"hash/crc32"
-	"net"
-	"sort"
-	"strings"
-	"time"
-
-	"github.com/google/gopacket"
-	"github.com/google/gopacket/pcap"
-)
-
-var _ PacketIO = (*pcapPacketIO)(nil)
-
-type pcapPacketIO struct {
-	pcap     *pcap.Handle
-	lastTime *time.Time
-	ioCancel context.CancelFunc
-	config   PcapPacketIOConfig
-
-	dialer *net.Dialer
-}
-
-type PcapPacketIOConfig struct {
-	PcapFile string
-	Realtime bool
-}
-
-func NewPcapPacketIO(config PcapPacketIOConfig) (PacketIO, error) {
-	handle, err := pcap.OpenOffline(config.PcapFile)
-	if err != nil {
-		return nil, err
-	}
-
-	return &pcapPacketIO{
-		pcap:     handle,
-		lastTime: nil,
-		ioCancel: nil,
-		config:   config,
-		dialer:   &net.Dialer{},
-	}, nil
-}
-
-func (p *pcapPacketIO) Register(ctx context.Context, cb PacketCallback) error {
-	go func() {
-		packetSource := gopacket.NewPacketSource(p.pcap, p.pcap.LinkType())
-		for packet := range packetSource.Packets() {
-			p.wait(packet)
-
-			networkLayer := packet.NetworkLayer()
-			if networkLayer != nil {
-				src, dst := networkLayer.NetworkFlow().Endpoints()
-				endpoints := []string{src.String(), dst.String()}
-				sort.Strings(endpoints)
-				id := crc32.Checksum([]byte(strings.Join(endpoints, ",")), crc32.IEEETable)
-
-				cb(&pcapPacket{
-					streamID:  id,
-					timestamp: packet.Metadata().Timestamp,
-					data:      packet.LinkLayer().LayerPayload(),
-				}, nil)
-			}
-		}
-		// Give the workers a chance to finish everything
-		time.Sleep(time.Second)
-		// Stop the engine when all packets are finished
-		p.ioCancel()
-	}()
-
-	return nil
-}
-
-// A normal dialer is sufficient as pcap IO does not mess up with the networking
-func (p *pcapPacketIO) ProtectedDialContext(ctx context.Context, network, address string) (net.Conn, error) {
-	return p.dialer.DialContext(ctx, network, address)
-}
-
-func (p *pcapPacketIO) SetVerdict(pkt Packet, v Verdict, newPacket []byte) error {
-	return nil
-}
-
-func (p *pcapPacketIO) SetCancelFunc(cancelFunc context.CancelFunc) error {
-	p.ioCancel = cancelFunc
-	return nil
-}
-
-func (p *pcapPacketIO) Close() error {
-	p.pcap.Close()
-	return nil
-}
-
-// Intentionally slow down the replay
-// In realtime mode, this is to match the timestamps in the capture
-func (p *pcapPacketIO) wait(packet gopacket.Packet) error {
-	if !p.config.Realtime {
-		return nil
-	}
-
-	if p.lastTime == nil {
-		p.lastTime = &packet.Metadata().Timestamp
-	} else {
-		t := packet.Metadata().Timestamp.Sub(*p.lastTime)
-		time.Sleep(t)
-		p.lastTime = &packet.Metadata().Timestamp
-	}
-
-	return nil
-}
-
-var _ Packet = (*pcapPacket)(nil)
-
-type pcapPacket struct {
-	streamID  uint32
-	timestamp time.Time
-	data      []byte
-}
-
-func (p *pcapPacket) StreamID() uint32 {
-	return p.streamID
-}
-
-func (p *pcapPacket) Timestamp() time.Time {
-	return p.timestamp
-}
-
-func (p *pcapPacket) Data() []byte {
-	return p.data
-}