kubeshark/tap/tcp_assembler.go
David Levanon 01d6005a7b
minor logging changes (#499)
Co-authored-by: gadotroee <55343099+gadotroee@users.noreply.github.com>
2021-11-23 14:21:53 +02:00

139 lines
3.8 KiB
Go

package tap
import (
"encoding/hex"
"os"
"os/signal"
"sync"
"time"
"github.com/google/gopacket"
"github.com/google/gopacket/layers"
"github.com/google/gopacket/reassembly"
"github.com/up9inc/mizu/shared/logger"
"github.com/up9inc/mizu/tap/api"
"github.com/up9inc/mizu/tap/diagnose"
"github.com/up9inc/mizu/tap/source"
)
const PACKETS_SEEN_LOG_THRESHOLD = 1000
type tcpAssembler struct {
*reassembly.Assembler
streamPool *reassembly.StreamPool
streamFactory *tcpStreamFactory
assemblerMutex sync.Mutex
}
// Context
// The assembler context
type context struct {
CaptureInfo gopacket.CaptureInfo
}
func (c *context) GetCaptureInfo() gopacket.CaptureInfo {
return c.CaptureInfo
}
func NewTcpAssembler(outputItems chan *api.OutputChannelItem, streamsMap *tcpStreamMap, opts *TapOpts) *tcpAssembler {
var emitter api.Emitter = &api.Emitting{
AppStats: &diagnose.AppStats,
OutputChannel: outputItems,
}
streamFactory := NewTcpStreamFactory(emitter, streamsMap, opts)
streamPool := reassembly.NewStreamPool(streamFactory)
assembler := reassembly.NewAssembler(streamPool)
maxBufferedPagesTotal := GetMaxBufferedPagesPerConnection()
maxBufferedPagesPerConnection := GetMaxBufferedPagesTotal()
logger.Log.Infof("Assembler options: maxBufferedPagesTotal=%d, maxBufferedPagesPerConnection=%d",
maxBufferedPagesTotal, maxBufferedPagesPerConnection)
assembler.AssemblerOptions.MaxBufferedPagesTotal = maxBufferedPagesTotal
assembler.AssemblerOptions.MaxBufferedPagesPerConnection = maxBufferedPagesPerConnection
return &tcpAssembler{
Assembler: assembler,
streamPool: streamPool,
streamFactory: streamFactory,
}
}
func (a *tcpAssembler) processPackets(dumpPacket bool, packets <-chan source.TcpPacketInfo) {
signalChan := make(chan os.Signal, 1)
signal.Notify(signalChan, os.Interrupt)
for packetInfo := range packets {
packetsCount := diagnose.AppStats.IncPacketsCount()
if packetsCount % PACKETS_SEEN_LOG_THRESHOLD == 0 {
logger.Log.Debugf("Packets seen: #%d", packetsCount)
}
packet := packetInfo.Packet
data := packet.Data()
diagnose.AppStats.UpdateProcessedBytes(uint64(len(data)))
if dumpPacket {
logger.Log.Debugf("Packet content (%d/0x%x) - %s", len(data), len(data), hex.Dump(data))
}
tcp := packet.Layer(layers.LayerTypeTCP)
if tcp != nil {
diagnose.AppStats.IncTcpPacketsCount()
tcp := tcp.(*layers.TCP)
if *checksum {
err := tcp.SetNetworkLayerForChecksum(packet.NetworkLayer())
if err != nil {
logger.Log.Fatalf("Failed to set network layer for checksum: %s", err)
}
}
c := context{
CaptureInfo: packet.Metadata().CaptureInfo,
}
diagnose.InternalStats.Totalsz += len(tcp.Payload)
logger.Log.Debugf("%s:%v -> %s:%v", packet.NetworkLayer().NetworkFlow().Src(), tcp.SrcPort, packet.NetworkLayer().NetworkFlow().Dst(), tcp.DstPort)
a.assemblerMutex.Lock()
a.AssembleWithContext(packet.NetworkLayer().NetworkFlow(), tcp, &c)
a.assemblerMutex.Unlock()
}
done := *maxcount > 0 && int64(diagnose.AppStats.PacketsCount) >= *maxcount
if done {
errorMapLen, _ := diagnose.TapErrors.GetErrorsSummary()
logger.Log.Infof("Processed %v packets (%v bytes) in %v (errors: %v, errTypes:%v)",
diagnose.AppStats.PacketsCount,
diagnose.AppStats.ProcessedBytes,
time.Since(diagnose.AppStats.StartTime),
diagnose.TapErrors.ErrorsCount,
errorMapLen)
}
select {
case <-signalChan:
logger.Log.Infof("Caught SIGINT: aborting")
done = true
default:
// NOP: continue
}
if done {
break
}
}
a.assemblerMutex.Lock()
closed := a.FlushAll()
a.assemblerMutex.Unlock()
logger.Log.Debugf("Final flush: %d closed", closed)
}
func (a *tcpAssembler) dumpStreamPool() {
a.streamPool.Dump()
}
func (a *tcpAssembler) waitAndDump() {
a.streamFactory.WaitGoRoutines()
a.assemblerMutex.Lock()
logger.Log.Debugf("%s", a.Dump())
a.assemblerMutex.Unlock()
}