Python 3.x 打印DNS信息时Pyshark属性错误

我在获取数据包的DNS信息时遇到pyshark问题。我正在使用Python3

我的代码如下所示：

    import pyshark
    cap = pyshark.LiveCapture(interface="en1")
    cap.sniff(timeout=5)

    def print_dns_info(pkt):
        if pkt.dns.qry_name:
            print 'DNS Request from %s: %s' % (pkt.ip.src, pkt.dns.qry_name)
        elif pkt.dns.resp_name:
            print 'DNS Response from %s: %s' % (pkt.ip.src, pkt.dns.resp_name)
    cap.apply_on_packets(print_dns_info, timeout=100)

Traceback (most recent call last):
  File "<pyshell#6>", line 1, in <module>
    cap.apply_on_packets(print_dns_info, timeout=100)
  File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/pyshark/capture/capture.py", line 201, in apply_on_packets
    return self.eventloop.run_until_complete(coro)
  File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/trollius/base_events.py", line 300, in run_until_complete
    return future.result()
  File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/trollius/futures.py", line 287, in result
    raise self._exception
  File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/trollius/tasks.py", line 255, in _step
    result = next(coro)
  File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/trollius/tasks.py", line 424, in wait_for
    raise Return(fut.result())
  File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/trollius/futures.py", line 287, in result
    raise self._exception
  File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/trollius/tasks.py", line 251, in _step
    result = coro.throw(exc)
  File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/pyshark/capture/capture.py", line 215, in packets_from_tshark
    packet_count=packet_count))
  File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/trollius/tasks.py", line 253, in _step
    result = coro.send(value)
  File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/pyshark/capture/capture.py", line 238, in _go_through_packets_from_fd
packet_callback(packet)
  File "<pyshell#5>", line 2, in print_dns_info
    if pkt.dns.qry_name:
  File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/pyshark/packet/packet.py", line 110, in __getattr__
    raise AttributeError()

错误如下所示：

    import pyshark
    cap = pyshark.LiveCapture(interface="en1")
    cap.sniff(timeout=5)

    def print_dns_info(pkt):
        if pkt.dns.qry_name:
            print 'DNS Request from %s: %s' % (pkt.ip.src, pkt.dns.qry_name)
        elif pkt.dns.resp_name:
            print 'DNS Response from %s: %s' % (pkt.ip.src, pkt.dns.resp_name)
    cap.apply_on_packets(print_dns_info, timeout=100)

Traceback (most recent call last):
  File "<pyshell#6>", line 1, in <module>
    cap.apply_on_packets(print_dns_info, timeout=100)
  File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/pyshark/capture/capture.py", line 201, in apply_on_packets
    return self.eventloop.run_until_complete(coro)
  File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/trollius/base_events.py", line 300, in run_until_complete
    return future.result()
  File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/trollius/futures.py", line 287, in result
    raise self._exception
  File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/trollius/tasks.py", line 255, in _step
    result = next(coro)
  File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/trollius/tasks.py", line 424, in wait_for
    raise Return(fut.result())
  File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/trollius/futures.py", line 287, in result
    raise self._exception
  File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/trollius/tasks.py", line 251, in _step
    result = coro.throw(exc)
  File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/pyshark/capture/capture.py", line 215, in packets_from_tshark
    packet_count=packet_count))
  File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/trollius/tasks.py", line 253, in _step
    result = coro.send(value)
  File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/pyshark/capture/capture.py", line 238, in _go_through_packets_from_fd
packet_callback(packet)
  File "<pyshell#5>", line 2, in print_dns_info
    if pkt.dns.qry_name:
  File "/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/pyshark/packet/packet.py", line 110, in __getattr__
    raise AttributeError()

回溯（最近一次呼叫最后一次）：
文件“”，第1行，在
对数据包应用上限（打印dns信息，超时=100）
文件“/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site packages/pyshark/capture/capture.py”，第201行，在apply\u on\u数据包中
返回self.eventloop。运行\u直到完成（coro）
文件“/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site packages/trollius/base_events.py”，第300行，运行_直到_完成
返回future.result（）
结果文件为“/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site packages/trollius/futures.py”，第287行
提出自己的意见
文件“/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site packages/trollius/tasks.py”，第255行，步骤
结果=下一个（coro）
文件“/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site packages/trollius/tasks.py”，第424行，等待
上升返回（未来结果（））
结果文件为“/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site packages/trollius/futures.py”，第287行
提出自己的意见
文件“/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site packages/trollius/tasks.py”，第251行，步骤
结果=核心投掷（exc）
文件“/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site-packages/pyshark/capture/capture.py”，第215行，来自_-tshark的数据包
数据包计数=数据包计数）
文件“/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site packages/trollius/tasks.py”，第253行，步骤
结果=coro.send（值）
文件“/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site packages/pyshark/capture/capture.py”，第238行，从fd到fd
数据包回调（数据包）
文件“”，第2行，在打印\u dns\u信息中
如果pkt.dns.qry_名称：
文件“/Library/Frameworks/Python.framework/Versions/3.5/lib/python3.5/site packages/pyshark/packet/packet.py”，第110行，在__
raise AttributeError（）

---

我甚至不打印任何关于数据包的信息，只打印错误。

您可以将其包装成try/except，忽略所有非DNS数据包

    try:
        if pkt.dns.qry_name:
            print 'DNS Request from %s: %s' % (pkt.ip.src, pkt.dns.qry_name)
    except AttributeError as e:
        #ignore packets that aren't DNS Request
        pass
    try:
        if pkt.dns.resp_name:
            print 'DNS Response from %s: %s' % (pkt.ip.src, pkt.dns.resp_name)
    except AttributeError as e:
        #ignore packets that aren't DNS Response
        pass