Golang C.pcap_activate类(方法)实例源码

// Activate should only be called on a Pcap that was obtained through Create.
func (p *Pcap) Activate() error {
	res := int32(C.pcap_activate(p.cptr))
	if res < 0 {
		return fmt.Errorf("%s(errnum=%d)", Statustostr(res), res)
	}
	return nil
}

// Activate the packet source. Note that after calling this method it will not
// be possible to change the packet source configuration (MTU, promiscuous mode,
// monitor mode, ...)
func (h *Handle) Activate() error {
	err := C.pcap_activate(h.pcap)
	if err < 0 {
		return fmt.Errorf("Could not activate: %s", h.get_error())
	}

	return nil
}

// Activate activates the handle.  The current InactiveHandle becomes invalid
// and all future function calls on it will fail.
func (p *InactiveHandle) Activate() (*Handle, error) {
	err := activateError(C.pcap_activate(p.cptr))
	if err != aeNoError {
		return nil, err
	}
	h := &Handle{cptr: p.cptr, device: p.device, blockForever: p.blockForever}
	p.cptr = nil
	return h, nil
}

func main() {
	var errbuf = (*C.char)(C.malloc(C.PCAP_ERRBUF_SIZE))
	defer C.free(unsafe.Pointer(errbuf))
	var source = C.CString("any")
	defer C.free(unsafe.Pointer(source))

	pcap_handle := C.pcap_create(source, errbuf)
	if pcap_handle == nil {
		panic("pcap_handle")
	}
	C.pcap_set_buffer_size(pcap_handle, 2*1024*1024)
	C.pcap_set_promisc(pcap_handle, 1)
	C.pcap_set_snaplen(pcap_handle, 512) // more than enough to recognize a WOL packet
	C.pcap_setdirection(pcap_handle, C.PCAP_D_IN)
	if C.pcap_activate(pcap_handle) != 0 {
		panic(C.GoString(C.pcap_geterr(pcap_handle)))
	}

	var bpf_program C.struct_bpf_program
	if C.pcap_compile(pcap_handle, &bpf_program, pcap_filter, 0, 0) != 0 {
		panic(C.GoString(C.pcap_geterr(pcap_handle)))
	}
	if C.pcap_setfilter(pcap_handle, &bpf_program) != 0 {
		panic(C.GoString(C.pcap_geterr(pcap_handle)))
	}

	for {
		var pkt_header *C.struct_pcap_pkthdr
		var pkt_data *C.u_char
		if C.pcap_next_ex(pcap_handle, &pkt_header, &pkt_data) < 0 {
			panic(C.GoString(C.pcap_geterr(pcap_handle)))
		}
		if pkt_data == nil {
			continue
		}
		data := make([]byte, pkt_header.caplen)
		copy(data, (*(*[10000000]byte)(unsafe.Pointer(pkt_data)))[0:])
		from_mac, to_mac := checkwol(data)
		if from_mac != "" {
			fmt.Printf("%v: %v sends WOL to %v\n", time.Now(), from_mac, to_mac)
		}
	}

}

// Activate a packet capture handle to look at packets on the network, with the options that
// were set on the handle being in effect.
func (p *Pcap) Activate() error {
	if C.pcap_activate(p.cptr) != 0 {
		return p.Geterror()
	}
	return nil
}

func (p *Handle) activation() {
	C.pcap_activate(p.cptr)
}