Make default pid to be -1 and remove unsafe code

firewall/interception/ebpf/bandwidth/interface.go

@@ -1,17 +1,17 @@
 package ebpf
 
 import (
+	"encoding/binary"
 	"fmt"
 	"net"
 	"path/filepath"
 	"syscall"
-	"time"
-	"unsafe"
 
 	"github.com/cilium/ebpf"
 	"github.com/cilium/ebpf/link"
 	"github.com/cilium/ebpf/rlimit"
 	"github.com/safing/portbase/log"
+	"github.com/safing/portmaster/network/packet"
 	"golang.org/x/sys/unix"
 )
 
@@ -28,6 +28,7 @@ var ebpfInterface = struct {
 	objs: bpfObjects{},
 }
 
+// SetupBandwidthInterface initializes the ebpf interface and starts gattering bandwidth information for all connections.
 func SetupBandwidthInterface() error {
 
 	// Allow the current process to lock memory for eBPF resources.
@@ -141,6 +142,7 @@ func ShutdownBandwithInterface() {
 	ebpfInterface.objs.Close()
 }
 
+// findCgroupPath returns the default unified path of the cgroup
 func findCgroupPath() (string, error) {
 	cgroupPath := "/sys/fs/cgroup"
 
@@ -156,24 +158,31 @@ func findCgroupPath() (string, error) {
 	return cgroupPath, nil
 }
 
+// printBandwidthData prints the contencs of the shared map in the ebpf program.
 func printBandwidthData() {
 	iter := ebpfInterface.objs.bpfMaps.PmBandwidthMap.Iterate()
 	var skKey bpfSkKey
 	var skInfo bpfSkInfo
 	for iter.Next(&skKey, &skInfo) {
 		log.Debugf("Connection: %d %s:%d %s:%d %d %d", skKey.Protocol,
-			arrayToIP(skKey.SrcIp, skKey.Ipv6).String(), skKey.SrcPort,
-			arrayToIP(skKey.DstIp, skKey.Ipv6).String(), skKey.DstPort,
+			convertArrayToIPv4(skKey.SrcIp, packet.IPVersion(skKey.Ipv6)).String(), skKey.SrcPort,
+			convertArrayToIPv4(skKey.DstIp, packet.IPVersion(skKey.Ipv6)).String(), skKey.DstPort,
 			skInfo.Rx, skInfo.Tx,
 		)
 	}
 }
 
-// arrayToIP converts IP number array to net.IP
-func arrayToIP(ipNum [4]uint32, ipv6 uint8) net.IP {
-	if ipv6 == 0 {
-		return unsafe.Slice((*byte)(unsafe.Pointer(&ipNum)), 4)
+// convertArrayToIPv4 converts an array of uint32 values to an IPv4 net.IP address.
+func convertArrayToIPv4(input [4]uint32, ipVersion packet.IPVersion) net.IP {
+	if ipVersion == packet.IPv4 {
+		addressBuf := make([]byte, 4)
+		binary.LittleEndian.PutUint32(addressBuf, input[0])
+		return net.IP(addressBuf)
 	} else {
-		return unsafe.Slice((*byte)(unsafe.Pointer(&ipNum)), 16)
+		addressBuf := make([]byte, 16)
+		for i := 0; i < 4; i++ {
+			binary.LittleEndian.PutUint32(addressBuf[i*4:i*4+4], input[i])
+		}
+		return net.IP(addressBuf)
 	}
 }

firewall/interception/ebpf/connection_listener/worker.go

@@ -5,7 +5,6 @@ import (
 	"encoding/binary"
 	"errors"
 	"net"
-	"unsafe"
 
 	"github.com/cilium/ebpf/link"
 	"github.com/cilium/ebpf/ringbuf"
@@ -15,8 +14,10 @@ import (
 )
 
 //go:generate go run github.com/cilium/ebpf/cmd/bpf2go -cc clang -cflags "-O2 -g -Wall -Werror" -type Event bpf ../programs/monitor.c
+
 var stopper chan struct{}
 
+// StartEBPFWorker starts the ebpf worker.
 func StartEBPFWorker(ch chan packet.Packet) {
 	stopper = make(chan struct{})
 	go func() {
@@ -32,7 +33,7 @@ func StartEBPFWorker(ch chan packet.Packet) {
 			log.Errorf("ebpf: failed to load ebpf object: %s", err)
 			return
 		}
-		defer objs.Close()
+		defer objs.Close() //nolint:errcheck
 
 		// Create a link to the tcp_connect program.
 		linkTCPConnect, err := link.AttachTracing(link.TracingOptions{
@@ -42,7 +43,7 @@ func StartEBPFWorker(ch chan packet.Packet) {
 			log.Errorf("ebpf: failed to attach to tcp_v4_connect: %s ", err)
 			return
 		}
-		defer linkTCPConnect.Close()
+		defer linkTCPConnect.Close() //nolint:errcheck
 
 		// Create a link to the udp_v4_connect program.
 		linkUDPV4, err := link.AttachTracing(link.TracingOptions{
@@ -52,7 +53,7 @@ func StartEBPFWorker(ch chan packet.Packet) {
 			log.Errorf("ebpf: failed to attach to udp_v4_connect: %s ", err)
 			return
 		}
-		defer linkUDPV4.Close()
+		defer linkUDPV4.Close() //nolint:errcheck
 
 		// Create a link to the udp_v6_connect program.
 		linkUDPV6, err := link.AttachTracing(link.TracingOptions{
@@ -62,7 +63,7 @@ func StartEBPFWorker(ch chan packet.Packet) {
 			log.Errorf("ebpf: failed to attach to udp_v6_connect: %s ", err)
 			return
 		}
-		defer linkUDPV6.Close()
+		defer linkUDPV6.Close() //nolint:errcheck
 
 		rd, err := ringbuf.NewReader(objs.bpfMaps.PmConnectionEvents)
 		if err != nil {
@@ -105,8 +106,8 @@ func StartEBPFWorker(ch chan packet.Packet) {
 				Protocol: packet.IPProtocol(event.Protocol),
 				SrcPort:  event.Sport,
 				DstPort:  event.Dport,
-				Src:      arrayToIP(event.Saddr, packet.IPVersion(event.IpVersion)),
-				Dst:      arrayToIP(event.Daddr, packet.IPVersion(event.IpVersion)),
+				Src:      convertArrayToIPv4(event.Saddr, packet.IPVersion(event.IpVersion)),
+				Dst:      convertArrayToIPv4(event.Daddr, packet.IPVersion(event.IpVersion)),
 				PID:      int(event.Pid),
 			}
 			if isEventValid(event) {
@@ -123,19 +124,30 @@ func StartEBPFWorker(ch chan packet.Packet) {
 	}()
 }
 
+// StopEBPFWorker stops the ebpf worker.
 func StopEBPFWorker() {
 	close(stopper)
 }
 
+// isEventValid checks whether the given bpfEvent is valid or not.
+// It returns true if the event is valid, otherwise false.
 func isEventValid(event bpfEvent) bool {
+	// Check if the destination port is 0
 	if event.Dport == 0 {
 		return false
 	}
 
+	// Check if the source port is 0
 	if event.Sport == 0 {
 		return false
 	}
 
+	// Check if the process ID is 0
+	if event.Pid == 0 {
+		return false
+	}
+
+	// If the IP version is IPv4
 	if event.IpVersion == 4 {
 		if event.Saddr[0] == 0 {
 			return false
@@ -148,11 +160,17 @@ func isEventValid(event bpfEvent) bool {
 	return true
 }
 
-// arrayToIP converts IP number array to net.IP
-func arrayToIP(ipNum [4]uint32, ipVersion packet.IPVersion) net.IP {
+// convertArrayToIPv4 converts an array of uint32 values to an IPv4 net.IP address.
+func convertArrayToIPv4(input [4]uint32, ipVersion packet.IPVersion) net.IP {
 	if ipVersion == packet.IPv4 {
-		return unsafe.Slice((*byte)(unsafe.Pointer(&ipNum)), 4)
+		addressBuf := make([]byte, 4)
+		binary.LittleEndian.PutUint32(addressBuf, input[0])
+		return net.IP(addressBuf)
 	} else {
-		return unsafe.Slice((*byte)(unsafe.Pointer(&ipNum)), 16)
+		addressBuf := make([]byte, 16)
+		for i := 0; i < 4; i++ {
+			binary.LittleEndian.PutUint32(addressBuf[i*4:i*4+4], input[i])
+		}
+		return net.IP(addressBuf)
 	}
 }