TRA-3212 Passive-Tapper and Mizu share code (#70)

* Use log in tap package instead of fmt. * Moved api/pkg/tap to root. * Added go.mod and go.sum for tap. * Added replace for shared. * api uses tap module instead of tap package. * Removed dependency of tap in shared by moving env var out of tap. * Fixed compilation bugs. * Fixed: Forgot to export struct field HostMode. * Removed unused flag. * Close har output channel when done. * Moved websocket out of mizu and into passive-tapper. * Send connection details over har output channel. * Fixed compilation errors. * Removed unused info from request response cache. * Renamed connection -> connectionID. * Fixed rename bug. * Export setters and getters for filter ips and ports. * Added tap dependency to Dockerfile. * Uncomment error messages. * Renamed `filterIpAddresses` -> `filterAuthorities`. * Renamed ConnectionID -> ConnectionInfo. * Fixed: Missed one replace.
2025-09-26 04:54:36 +00:00 · 2021-06-14 13:22:44 +03:00
parent 31dcfc4b2e
commit 135b1a5e1e
23 changed files with 442 additions and 700 deletions
--- a/tap/tcp_stream_factory.go
+++ b/tap/tcp_stream_factory.go
@@ -0,0 +1,118 @@
+package tap
+
+import (
+	"fmt"
+	"sync"
+
+	"github.com/google/gopacket"
+	"github.com/google/gopacket/layers" // pulls in all layers decoders
+	"github.com/google/gopacket/reassembly"
+)
+
+/*
+ * The TCP factory: returns a new Stream
+ * Implements gopacket.reassembly.StreamFactory interface (New)
+ * Generates a new tcp stream for each new tcp connection. Closes the stream when the connection closes.
+ */
+type tcpStreamFactory struct {
+	wg                 sync.WaitGroup
+	doHTTP             bool
+	harWriter          *HarWriter
+	outbountLinkWriter *OutboundLinkWriter
+}
+
+func (factory *tcpStreamFactory) New(net, transport gopacket.Flow, tcp *layers.TCP, ac reassembly.AssemblerContext) reassembly.Stream {
+	Debug("* NEW: %s %s", net, transport)
+	fsmOptions := reassembly.TCPSimpleFSMOptions{
+		SupportMissingEstablishment: *allowmissinginit,
+	}
+	Debug("Current App Ports: %v", gSettings.filterPorts)
+	dstIp := net.Dst().String()
+	dstPort := int(tcp.DstPort)
+
+	if factory.shouldNotifyOnOutboundLink(dstIp, dstPort) {
+		factory.outbountLinkWriter.WriteOutboundLink(net.Src().String(), dstIp, dstPort)
+	}
+	isHTTP := factory.shouldTap(dstIp, dstPort)
+	stream := &tcpStream{
+		net:        net,
+		transport:  transport,
+		isDNS:      tcp.SrcPort == 53 || tcp.DstPort == 53,
+		isHTTP:     isHTTP && factory.doHTTP,
+		reversed:   tcp.SrcPort == 80,
+		tcpstate:   reassembly.NewTCPSimpleFSM(fsmOptions),
+		ident:      fmt.Sprintf("%s:%s", net, transport),
+		optchecker: reassembly.NewTCPOptionCheck(),
+	}
+	if stream.isHTTP {
+		stream.client = httpReader{
+			msgQueue: make(chan httpReaderDataMsg),
+			ident:    fmt.Sprintf("%s %s", net, transport),
+			tcpID: tcpID{
+				srcIP:   net.Src().String(),
+				dstIP:   net.Dst().String(),
+				srcPort: transport.Src().String(),
+				dstPort: transport.Dst().String(),
+			},
+			hexdump:  *hexdump,
+			parent:   stream,
+			isClient: true,
+			harWriter: factory.harWriter,
+		}
+		stream.server = httpReader{
+			msgQueue: make(chan httpReaderDataMsg),
+			ident:    fmt.Sprintf("%s %s", net.Reverse(), transport.Reverse()),
+			tcpID: tcpID{
+				srcIP:   net.Dst().String(),
+				dstIP:   net.Src().String(),
+				srcPort: transport.Dst().String(),
+				dstPort: transport.Src().String(),
+			},
+			hexdump: *hexdump,
+			parent:  stream,
+			harWriter: factory.harWriter,
+		}
+		factory.wg.Add(2)
+		// Start reading from channels stream.client.bytes and stream.server.bytes
+		go stream.client.run(&factory.wg)
+		go stream.server.run(&factory.wg)
+	}
+	return stream
+}
+
+func (factory *tcpStreamFactory) WaitGoRoutines() {
+	factory.wg.Wait()
+}
+
+func (factory *tcpStreamFactory) shouldTap(dstIP string, dstPort int) bool {
+	if hostMode {
+		if inArrayString(gSettings.filterAuthorities, fmt.Sprintf("%s:%d", dstIP, dstPort)) == true {
+			return true
+		} else if inArrayString(gSettings.filterAuthorities, dstIP) == true {
+			return true
+		}
+		return false
+	} else {
+		isTappedPort := dstPort == 80 || (gSettings.filterPorts != nil && (inArrayInt(gSettings.filterPorts, dstPort)))
+		if !isTappedPort {
+			return false
+		}
+
+		if !*anydirection {
+			isDirectedHere := inArrayString(ownIps, dstIP)
+			if !isDirectedHere {
+				return false
+			}
+		}
+
+		return true
+	}
+}
+
+func (factory *tcpStreamFactory) shouldNotifyOnOutboundLink(dstIP string, dstPort int) bool {
+	if inArrayInt(remoteOnlyOutboundPorts, dstPort) {
+		isDirectedHere := inArrayString(ownIps, dstIP)
+		return !isDirectedHere && !isPrivateIP(dstIP)
+	}
+	return true
+}