optimize: adapt to bpf legacy

pkg/ebpf_internal/rawsock.go

@@ -0,0 +1,31 @@
+// Copied from https://github.com/cilium/ebpf/blob/v0.10.0/example_sock_elf_test.go
+
+package internal
+
+import (
+	"encoding/binary"
+	"syscall"
+	"unsafe"
+)
+
+func OpenRawSock(index int) (int, error) {
+	sock, err := syscall.Socket(syscall.AF_PACKET, syscall.SOCK_RAW|syscall.SOCK_NONBLOCK|syscall.SOCK_CLOEXEC, int(Htons(syscall.ETH_P_ALL)))
+	if err != nil {
+		return 0, err
+	}
+	sll := syscall.SockaddrLinklayer{
+		Ifindex:  index,
+		Protocol: Htons(syscall.ETH_P_ALL),
+	}
+	if err := syscall.Bind(sock, &sll); err != nil {
+		return 0, err
+	}
+	return sock, nil
+}
+
+// Htons converts the unsigned short integer hostshort from host byte order to network byte order.
+func Htons(i uint16) uint16 {
+	b := make([]byte, 2)
+	binary.BigEndian.PutUint16(b, i)
+	return *(*uint16)(unsafe.Pointer(&b[0]))
+}