Python Scapy --arp 请求和响应

Python Scapy --arp request and response

提问by Bob Ebert

I send a arp packet broadcast with this line:

我用这一行发送一个 arp 数据包广播：

send(ARP(op=ARP.who_has, psrc="192.168.5.51", pdst=the_ip))

My question is: How can I view the response (in this case: the mac of the remote ip)? I know I can do:

我的问题是：如何查看响应（在这种情况下：远程 ip 的 mac）？我知道我可以做到：

pkt = sniff(filter=arp , count=10) 
print (pkt.summary()) 

But I do not want to count the packets because I do not know when it will be printed (could be in the next 10 or 100 packets)

但我不想计算数据包，因为我不知道什么时候会打印它（可能在接下来的 10 或 100 个数据包中）

Is there a way to while it is sniffing, to print the summary and thus, see the mac adress I am looking for?

有没有办法在嗅探时打印摘要，从而查看我正在寻找的 mac 地址？

Edit: I have an idea, Could I sniff 10 packets, if there is the ip in the packets print the mac adress, else sniff 10 more packets... This technique doesn't seems to be a good one tho...

编辑：我有一个想法，我可以嗅探 10 个数据包，如果数据包中的 ip 打印 mac 地址，否则再嗅探 10 个数据包......这种技术似乎不是一个好的技术......

采纳答案by Yoel

Scapy's user manualsuggests using the sr()or sr1()function for sending packets and receiving answers:

Scapy的用户手册建议使用sr()orsr1()函数发送数据包和接收答案：

The sr()function is for sending packets and receiving answers. The function returns a couple of packet and answers, and the unanswered packets. The function sr1()is a variant that only returns one packet that answered the packet (or the packet set) sent. The packets must be layer 3 packets (IP, ARP, etc.). The function srp()does the same for layer 2 packets (Ethernet, 802.3, etc.)

该sr()功能用于发送数据包和接收应答。该函数返回几个数据包和答案，以及未应答的数据包。该函数sr1()是一个变体，它只返回一个响应发送的数据包（或数据包集）的数据包。数据包必须是第 3 层数据包（IP、ARP等）。该函数srp()对第 2 层数据包（以太网、802.3等）执行相同的操作

The official API documentationspecifies their full signature. These seem to be the relevant arguments for this use-case:

官方 API 文档指定了它们的完整签名。这些似乎是此用例的相关参数：

retry: if positive, how many times to resend unanswered packets. if negative, how many consecutive unanswered probes before giving up. Only the negative value is really useful.
timeout: how much time to wait after the last packet has been sent. By default, srwill wait forever and the user will have to interrupt (Ctrl-C) it when he expects no more answers.
inter: time in seconds to wait between each packet sent.

retry: 如果是肯定的，重新发送未应答数据包的次数。如果是否定的，则在放弃之前有多少连续未回答的探测。只有负值才是真正有用的。
timeout：发送最后一个数据包后要等待多长时间。默认情况下，sr将永远等待，用户将不得不在他期望没有更多答案时中断（Ctrl-C）。
inter：在发送的每个数据包之间等待的时间（以秒为单位）。

Here is an execution example with the sr()function:

以下是该sr()函数的执行示例：

In [1]: from scapy.all import *
WARNING: No route found for IPv6 destination :: (no default route?)

In [2]: results, unanswered = sr(ARP(op=ARP.who_has, psrc='192.168.1.2', pdst='192.168.1.1'))
Begin emission:
.....*Finished to send 1 packets.

Received 6 packets, got 1 answers, remaining 0 packets

In [3]: results
Out[3]: <Results: TCP:0 UDP:0 ICMP:0 Other:1>

In [4]: result = results[0]

In [5]: result
Out[5]: 
(<ARP  op=who-has psrc=192.168.1.2 pdst=192.168.1.1 |>,
 <ARP  hwtype=0x1 ptype=0x800 hwlen=6 plen=4 op=is-at hwsrc=XX:XX:XX:XX:XX:XX psrc=192.168.1.1 hwdst=XX:XX:XX:XX:XX:XX pdst=192.168.1.2 |>)

In [6]: original_packet, answer = result

In [7]: original_packet
Out[7]: <ARP  op=who-has psrc=192.168.1.2 pdst=192.168.1.1 |>

In [8]: answer
Out[8]: <ARP  hwtype=0x1 ptype=0x800 hwlen=6 plen=4 op=is-at hwsrc=XX:XX:XX:XX:XX:XX psrc=192.168.1.1 hwdst=XX:XX:XX:XX:XX:XX pdst=192.168.1.2 |>

Here is an execution example with the sr1()function:

以下是该sr1()函数的执行示例：

In [9]: result = sr1(ARP(op=ARP.who_has, psrc='192.168.1.2', pdst='192.168.1.1'))
Begin emission:
.....Finished to send 1 packets.
*
Received 6 packets, got 1 answers, remaining 0 packets

In [10]: result
Out[10]: <ARP  hwtype=0x1 ptype=0x800 hwlen=6 plen=4 op=is-at hwsrc=XX:XX:XX:XX:XX:XX psrc=192.168.1.1 hwdst=XX:XX:XX:XX:XX:XX pdst=192.168.1.2 |>