🐙 adding advanced IP packet debugging

SkyPierIO · Aug 22, 2024 · cf872b5 · cf872b5
1 parent f8066f2
commit cf872b5
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Showing 3 changed files with 125 additions and 18 deletions.
diff --git a/pkg/utils/ip.go b/pkg/utils/ip.go
@@ -1,7 +1,9 @@
 package utils
 
 import (
+	"encoding/binary"
 	"fmt"
+	"log"
 	"net"
 )
 
@@ -34,4 +36,51 @@ func IsPublicIP(ipStr string) bool {
 	}
 
 	return true // IP is public
-}
+}
+
+func PrettyPrintIPHeader(packet []byte, level string) {
+	color := Cyan
+	switch level {
+	case "DEBUG":
+		color = Orange
+	case "ERROR":
+		color = Red
+	default:
+		color = Cyan
+	}
+	if len(packet) < 20 {
+		log.Println(Orange, "Packet too short", Reset)
+		return
+	}
+
+	version := packet[0] >> 4
+	ihl := packet[0] & 0x0F
+	tos := packet[1]
+	totalLength := binary.BigEndian.Uint16(packet[2:4])
+	identification := binary.BigEndian.Uint16(packet[4:6])
+	flags := packet[6] >> 5
+	fragmentOffset := binary.BigEndian.Uint16(packet[6:8]) & 0x1FFF
+	ttl := packet[8]
+	protocol := GetProtocolById(packet[9])
+	headerChecksum := binary.BigEndian.Uint16(packet[10:12])
+	sourceAddress := net.IP(packet[12:16])
+	destinationAddress := net.IP(packet[16:20])
+
+	log.Println(color, "IP Header:", Reset)
+	log.Println(color, "+---------------------+---------------------+", Reset)
+	log.Println(color, "| Field               | Value               |", Reset)
+	log.Println(color, "+---------------------+---------------------+", Reset)
+	log.Printf(" %s| %-19s | %-19d |%s\n", color, "Version", version, Reset)
+	log.Printf(" %s| %-19s | %-19d |%s\n", color, "IHL", ihl, Reset)
+	log.Printf(" %s| %-19s | %-19d |%s\n", color, "Type of Service", tos, Reset)
+	log.Printf(" %s| %-19s | %-19d |%s\n", color, "Total Length", totalLength, Reset)
+	log.Printf(" %s| %-19s | %-19d |%s\n", color, "Identification", identification, Reset)
+	log.Printf(" %s| %-19s | %-19d |%s\n", color, "Flags", flags, Reset)
+	log.Printf(" %s| %-19s | %-19d |%s\n", color, "Fragment Offset", fragmentOffset, Reset)
+	log.Printf(" %s| %-19s | %-19d |%s\n", color, "Time to Live", ttl, Reset)
+	log.Printf(" %s| %-19s | %v    |%s\n", color, "Protocol", protocol, Reset)
+	log.Printf(" %s| %-19s | %-19d |%s\n", color, "Header Checksum", headerChecksum, Reset)
+	log.Printf(" %s| %-19s | %-19s |%s\n", color, "Source Address", sourceAddress, Reset)
+	log.Printf(" %s| %-19s | %-19s |%s\n", color, "Destination Address", destinationAddress, Reset)
+	log.Println(color, "+---------------------+---------------------+", Reset)
+}
diff --git a/pkg/utils/test_utils.go b/pkg/utils/test_utils.go
@@ -0,0 +1,63 @@
+package utils
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/gin-gonic/gin"
+)
+
+func TestNickname(t *testing.T) {
+	router := gin.Default()
+	router.GET("/nickname", Nickname)
+
+	w := httptest.NewRecorder()
+	req, _ := http.NewRequest("GET", "/nickname", nil)
+	router.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Errorf("Expected status code %d, but got %d", http.StatusOK, w.Code)
+	}
+
+	expected := `{"Nickname":"your-nickname"}`
+	if w.Body.String() != expected {
+		t.Errorf("Expected body %s, but got %s", expected, w.Body.String())
+	}
+}
+
+func TestPing(t *testing.T) {
+	router := gin.Default()
+	router.GET("/ping", Ping)
+
+	w := httptest.NewRecorder()
+	req, _ := http.NewRequest("GET", "/ping", nil)
+	router.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Errorf("Expected status code %d, but got %d", http.StatusOK, w.Code)
+	}
+
+	expected := `{"message":"pong"}`
+	if w.Body.String() != expected {
+		t.Errorf("Expected body %s, but got %s", expected, w.Body.String())
+	}
+}
+
+func TestOk(t *testing.T) {
+	router := gin.Default()
+	router.GET("/", Ok)
+
+	w := httptest.NewRecorder()
+	req, _ := http.NewRequest("GET", "/", nil)
+	router.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Errorf("Expected status code %d, but got %d", http.StatusOK, w.Code)
+	}
+
+	expected := `{"message":"OK"}`
+	if w.Body.String() != expected {
+		t.Errorf("Expected body %s, but got %s", expected, w.Body.String())
+	}
+}
diff --git a/pkg/vpn/p2pEndpoints.go b/pkg/vpn/p2pEndpoints.go
@@ -6,7 +6,6 @@ import (
 	"encoding/hex"
 	"fmt"
 	"log"
-	"net"
 	"net/http"
 	"runtime"
 	"sync"
@@ -172,6 +171,7 @@ func Connect(node host.Host, dht *dht.IpfsDHT) gin.HandlerFunc {
 
 		// loop to read from the TUN interface and write to the libp2p stream.
 		doTx := func() {
+			var i int
 			packet := make([]byte, MTUSize)
 			for {
 				mu.Lock()
@@ -193,6 +193,8 @@ func Connect(node host.Host, dht *dht.IpfsDHT) gin.HandlerFunc {
 						// debug
 						header, _ := ipv4.ParseHeader(packet[:plen])
 						log.Printf("%vSending to remote: %+v (%+v)%v\n", utils.Green, header, err, utils.Reset)
+						log.Println(utils.Cyan, "Packet received", i, utils.Reset)
+						i++
 						continue
 					}
 				}
@@ -210,7 +212,7 @@ func Connect(node host.Host, dht *dht.IpfsDHT) gin.HandlerFunc {
 	return gin.HandlerFunc(fn)
 }
 
-func doRx(rw *bufio.ReadWriter, mu *sync.Mutex, inter *water.Interface) {
+func doRx(rw *bufio.ReadWriter, mu *sync.Mutex, inet *water.Interface) {
 	packet := make([]byte, MTUSize)
 	// packetSize := make([]byte, 2)
 	var i int
@@ -225,12 +227,17 @@ func doRx(rw *bufio.ReadWriter, mu *sync.Mutex, inter *water.Interface) {
 		}
 
 		// Decode the incoming packet's size from binary.
+		if len(packet) < 4 {
+			log.Fatal("packet too short")
+		}
 		size := binary.BigEndian.Uint16(packet[2:4])
 		// size := binary.LittleEndian.Uint16(packetSize)
 		// log.Println("receiving packet of size", size)
 		log.Println(utils.Orange, "receiving packet of size", size, packet[2:4], utils.Reset)
 		if size == 0 {
 			log.Println(utils.Red, packet, utils.Reset)
+			log.Println(utils.Red, hex.Dump(packet), utils.Reset)
+			utils.PrettyPrintIPHeader(packet, "ERROR")
 		}
 
 		// Read in the packet until completion.
@@ -247,28 +254,16 @@ func doRx(rw *bufio.ReadWriter, mu *sync.Mutex, inter *water.Interface) {
 		}
 
 		log.Println(utils.Orange, "\n"+hex.Dump(packet[:plen]), packet[:plen], plen, size, utils.Reset)
-		log.Println(utils.Orange, "───────────────────── IP packet ─────────────────────", utils.Reset)
-		// debug
-		header, _ := ipv4.ParseHeader(packet[:plen])
-		log.Printf("%vReading IP packet: %+v (%+v)%v\n", utils.Orange, header, err, utils.Reset)
-		proto := utils.GetProtocolById(packet[9])
-		log.Println(utils.Orange, "Packet Size:\t", packet[2:4], utils.Reset)
-		log.Println(utils.Orange, "Protocol:\t\t", proto, utils.Reset)
-		src := net.IPv4(packet[12], packet[13], packet[14], packet[15]).String()
-		log.Println(utils.Orange, "Source:\t\t", src, utils.Reset)
-		dst := net.IPv4(packet[16], packet[17], packet[18], packet[19]).String()
-		log.Println(utils.Orange, "Destination:\t", dst, utils.Reset)
-		log.Println(utils.Orange, "─────────────────────────────────────────────────────", utils.Reset)
-
+		utils.PrettyPrintIPHeader(packet, "DEBUG")
 		if size <= MTUSize && plen != 0 {
 			mu.Lock()
 			log.Println(utils.Orange, "mutex locked (writing to tun interface)", utils.Reset)
-			_, err = inter.Write(packet[:size])
+			_, err = inet.Write(packet[:size])
 			mu.Unlock()
 			log.Println(utils.Orange, "mutex unlocked", utils.Reset)
 			utils.Check(err)
 		}
-		log.Println(utils.Orange, i, utils.Reset)
+		log.Println(utils.Orange, "Packet written", i, utils.Reset)
 		i++
 	}
 }