Python arp嗅探原始套接字没有回复数据包

Question

为了更好地理解网络概念并提高我的python技能，我试图用python实现数据包嗅探器。 我刚开始学习python，所以代码当然可以优化;）

我已经实现了一个数据包嗅探器，它解压缩了以太网帧和arp头。 我想用原始套接字制作它，因为我想了解这些标题中的每个字节，所以请不要scapy帮助:)

问题是，我不会得到任何arp回复数据包。 它始终是操作码1和我

这是我的源代码：

import socket
import struct
import binascii

rawSocket = socket.socket(socket.PF_PACKET, socket.SOCK_RAW, socket.htons(0x0806))

while True:

    packet = rawSocket.recvfrom(2048)

    ethernet_header = packet[0][0:14]
    ethernet_detailed = struct.unpack("!6s6s2s", ethernet_header)

    arp_header = packet[0][14:42]
    arp_detailed = struct.unpack("2s2s1s1s2s6s4s6s4s", arp_header)

    print "****************_ETHERNET_FRAME_****************"
    print "Dest MAC:        ", binascii.hexlify(ethernet_detailed[0])
    print "Source MAC:      ", binascii.hexlify(ethernet_detailed[1])
    print "Type:            ", binascii.hexlify(ethernet_detailed[2])
    print "************************************************"
    print "******************_ARP_HEADER_******************"
    print "Hardware type:   ", binascii.hexlify(arp_detailed[0])
    print "Protocol type:   ", binascii.hexlify(arp_detailed[1])
    print "Hardware size:   ", binascii.hexlify(arp_detailed[2])
    print "Protocol size:   ", binascii.hexlify(arp_detailed[3])
    print "Opcode:          ", binascii.hexlify(arp_detailed[4])
    print "Source MAC:      ", binascii.hexlify(arp_detailed[5])
    print "Source IP:       ", socket.inet_ntoa(arp_detailed[6])
    print "Dest MAC:        ", binascii.hexlify(arp_detailed[7])
    print "Dest IP:         ", socket.inet_ntoa(arp_detailed[8])
    print "*************************************************\n"

有人可以解释一下我为什么没有得到这些响应包吗？

OUTPUT：

****************_ETHERNET_FRAME_****************
Dest MAC:         ffffffffffff
Source MAC:       0012bfc87243
Type:             0806
************************************************
******************_ARP_HEADER_******************
Hardware type:    0001
Protocol type:    0800
Hardware size:    06
Protocol size:    04
Opcode:           0001
Source MAC:       0012bfc87243
Source IP:        192.168.2.1
Dest MAC:         000000000000
Dest IP:          192.168.2.226
*************************************************

谢谢到目前为止！ :)

Answer 1

我认为您需要指定套接字协议号0x0003来嗅探所有内容，然后在事后过滤掉非ARP数据包。 这对我有用：

import socket
import struct
import binascii

rawSocket = socket.socket(socket.AF_PACKET, socket.SOCK_RAW, socket.htons(0x0003))

while True:

    packet = rawSocket.recvfrom(2048)

    ethernet_header = packet[0][0:14]
    ethernet_detailed = struct.unpack("!6s6s2s", ethernet_header)

    arp_header = packet[0][14:42]
    arp_detailed = struct.unpack("2s2s1s1s2s6s4s6s4s", arp_header)

    # skip non-ARP packets
    ethertype = ethernet_detailed[2]
    if ethertype != '\x08\x06':
        continue

    print "****************_ETHERNET_FRAME_****************"
    print "Dest MAC:        ", binascii.hexlify(ethernet_detailed[0])
    print "Source MAC:      ", binascii.hexlify(ethernet_detailed[1])
    print "Type:            ", binascii.hexlify(ethertype)
    print "************************************************"
    print "******************_ARP_HEADER_******************"
    print "Hardware type:   ", binascii.hexlify(arp_detailed[0])
    print "Protocol type:   ", binascii.hexlify(arp_detailed[1])
    print "Hardware size:   ", binascii.hexlify(arp_detailed[2])
    print "Protocol size:   ", binascii.hexlify(arp_detailed[3])
    print "Opcode:          ", binascii.hexlify(arp_detailed[4])
    print "Source MAC:      ", binascii.hexlify(arp_detailed[5])
    print "Source IP:       ", socket.inet_ntoa(arp_detailed[6])
    print "Dest MAC:        ", binascii.hexlify(arp_detailed[7])
    print "Dest IP:         ", socket.inet_ntoa(arp_detailed[8])
    print "*************************************************\n"

示例输出使用arpping从相同的主机和答复广播：

****************_ETHERNET_FRAME_****************
Dest MAC:         ffffffffffff
Source MAC:       000c29eb37bf
Type:             0806
************************************************
******************_ARP_HEADER_******************
Hardware type:    0001
Protocol type:    0800
Hardware size:    06
Protocol size:    04
Opcode:           0001
Source MAC:       000c29eb37bf
Source IP:        192.168.16.133
Dest MAC:         ffffffffffff
Dest IP:          192.168.16.2
*************************************************

****************_ETHERNET_FRAME_****************
Dest MAC:         000c29eb37bf
Source MAC:       005056f37861
Type:             0806
************************************************
******************_ARP_HEADER_******************
Hardware type:    0001
Protocol type:    0800
Hardware size:    06
Protocol size:    04
Opcode:           0002
Source MAC:       005056f37861
Source IP:        192.168.16.2
Dest MAC:         000c29eb37bf
Dest IP:          192.168.16.133
*************************************************