Re: [dts] [PATCH v7] framework/packet: support packet sniffer to specify running machine

["Tu, Lijuan" <lijuan.tu@intel.com>]

Applied, thanks

> -----Original Message-----
> From: phil.yang@arm.com [mailto:phil.yang@arm.com]
> Sent: Friday, October 19, 2018 5:25 PM
> To: dts@dpdk.org
> Cc: nd@arm.com; Tu, Lijuan <lijuan.tu@intel.com>
> Subject: [PATCH v7] framework/packet: support packet sniffer to specify
> running machine
> 
> By default, the Tester is supposed to be the server which running DTS and the
> packet sniff methods are running on it.
> However, if DTS was not running on the Tester and the Tester is another
> remote server, so packet sniff methods cannot sniff Tester's packets
> correctly.
> 
> This patch adds support for packet sniff methods to specify running machine
> and implements sniff packet methods in class tester.
> 
> 1. Add parameter to sniff_packet and load_sniff_pcap methods to specify
> the running machine.
> 2. Remove load_sniff_packets method in packet.py.
> 3. Add tcpdump_sniff_packets, load_tcpdump_sniff_pcap and
> load_tcpdump_sniff_packets for class tester with the new sniff_packet API.
> 4. Update tester.check_random_pkts method with
> tester.tcpdump_sniff_packets and tester.load_tcpdump_sniff_packets to
> make it execution on the Tester.
> 
> Signed-off-by: Phil Yang <phil.yang@arm.com>
> Suggested-by: Marvin Liu <yong.liu@intel.com>
> Suggested-by: Tu Lijuan <lijuan.tu@intel.com>
> ---
>  framework/packet.py | 97
> +++++++++++++++++++++++++----------------------------
>  framework/tester.py | 48 +++++++++++++++++++++++---
>  2 files changed, 89 insertions(+), 56 deletions(-)
> 
> diff --git a/framework/packet.py b/framework/packet.py index
> 976b82b..d5b8517 100755
> --- a/framework/packet.py
> +++ b/framework/packet.py
> @@ -33,7 +33,6 @@
>  Generic packet create, transmit and analyze module  Base on
> scapy(python program for packet manipulation)  """
> -
>  import os
>  import time
>  import sys
> @@ -61,6 +60,7 @@ from scapy.route import *  from scapy.packet import
> bind_layers, Raw  from scapy.sendrecv import sendp  from scapy.arch
> import get_if_hwaddr
> +from pexpect import pxssh
> 
>  # load extension layers
>  exec_file = os.path.realpath(__file__)
> @@ -812,15 +812,26 @@ def get_filter_cmd(filters=[]):
>          return ""
> 
> 
> -def sniff_packets(intf, count=0, timeout=5, filters=[]):
> +def sniff_packets(intf, count=0, timeout=5, filters=[], target=[]):
>      """
>      sniff all packets for certain port in certain seconds
>      """
>      param = ""
>      direct_param = r"(\s+)\[ (\S+) in\|out\|inout \]"
> -    tcpdump_help = subprocess.check_output("tcpdump -h; echo 0",
> -
> stderr=subprocess.STDOUT,
> -                                           shell=True)
> +
> +    try:
> +        tcpdump_help_session=pxssh.pxssh()
> +        tcpdump_help_session.login(server=target[0],
> username=target[1],
> +                                   password=target[2],
> original_prompt='[$#>]',
> +                                   login_timeout=20)
> +        tcpdump_help_session.sendline('tcpdump -h')
> +        tcpdump_help_session.prompt()
> +        tcpdump_help=tcpdump_help_session.before
> +        tcpdump_help_session.logout()
> +    except pxssh.ExceptionPxssh as e:
> +        print ('pxssh failed on login.')
> +        print (e)
> +
>      for line in tcpdump_help.split('\n'):
>          m = re.match(direct_param, line)
>          if m:
> @@ -850,16 +861,24 @@ def sniff_packets(intf, count=0, timeout=5,
> filters=[]):
>      else:
>          cmd = sniff_cmd % options
> 
> -    args = shlex.split(cmd)
> +    try:
> +        tcpdump_session=pxssh.pxssh()
> +        tcpdump_session.login(server=target[0], username=target[1],
> +                              password=target[2],
> original_prompt='[$#>]',
> +                              login_timeout=20)
> +        tcpdump_session.sendline(cmd)
> +        pipe = tcpdump_session
> +    except pxssh.ExceptionPxssh as e:
> +        print ('pxssh failed on login.')
> +        print (e)
> 
> -    pipe = subprocess.Popen(args)
>      index = str(time.time())
>      SNIFF_PIDS[index] = (pipe, intf, timeout)
>      time.sleep(1)
>      return index
> 
> 
> -def load_sniff_pcap(index=''):
> +def load_sniff_pcap(index='', target=[]):
>      """
>      Stop sniffer and return pcap file
>      """
> @@ -868,58 +887,36 @@ def load_sniff_pcap(index=''):
>          pipe, intf, timeout = SNIFF_PIDS[index]
>          time_elapse = int(time.time() - float(index))
>          while time_elapse < timeout:
> -            if pipe.poll() is not None:
> +            if pipe.prompt(timeout=1):
>                  child_exit = True
>                  break
> 
> -            time.sleep(1)
>              time_elapse += 1
> 
>          if not child_exit:
> -            pipe.send_signal(signal.SIGINT)
> -            pipe.wait()
> -
> -        # wait pcap file ready
> -        time.sleep(1)
> -        return "/tmp/sniff_%s.pcap" % intf
> -
> -    return ""
> -
> -
> -def load_sniff_packets(index=''):
> -    """
> -    Stop sniffer and return packet objects
> -    """
> -    pkts = []
> -    child_exit = False
> -    if index in SNIFF_PIDS.keys():
> -        pipe, intf, timeout = SNIFF_PIDS[index]
> -        time_elapse = int(time.time() - float(index))
> -        while time_elapse < timeout:
> -            if pipe.poll() is not None:
> +            try:
> +                # Stop Tcpdump on the target server
> +                tcpdump_quit_session=pxssh.pxssh()
> +                tcpdump_quit_session.login(server=target[0],
> username=target[1],
> +                                           password=target[2],
> original_prompt='[$#>]',
> +                                           login_timeout=20)
> +                tcpdump_quit_session.sendline('kill -2 $(pidof
> tcpdump)')
> +                tcpdump_quit_session.prompt()
> +                tcpdump_quit_session.logout()
>                  child_exit = True
> -                break
> +            except pxssh.ExceptionPxssh as e:
> +                print ('pxssh failed on login.')
> +                print (e)
> 
> -            time.sleep(1)
> -            time_elapse += 1
> -
> -        if not child_exit:
> -            pipe.send_signal(signal.SIGINT)
> -            pipe.wait()
> +        # Close the Tcpdump_session
> +        pipe.prompt()
> +        pipe.logout()
> 
>          # wait pcap file ready
>          time.sleep(1)
> -        try:
> -            cap_pkts = rdpcap("/tmp/sniff_%s.pcap" % intf)
> -            for pkt in cap_pkts:
> -                # packet gen should be scapy
> -                packet = Packet(tx_port=intf)
> -                packet.pktgen.assign_pkt(pkt)
> -                pkts.append(packet)
> -        except:
> -            pass
> +        return "/tmp/sniff_%s.pcap" % intf
> 
> -    return pkts
> +    return ""
> 
> 
>  def load_pcapfile(filename=""):
> @@ -978,12 +975,8 @@ def strip_pktload(pkt=None, layer="L2"):
> 
> ##############################################################
> #################
> 
> ##############################################################
> #################
>  if __name__ == "__main__":
> -    inst = sniff_packets("lo", timeout=5, filters=[{'layer': 'ether',
> -                         'config': {'dst': 'FF:FF:FF:FF:FF:FF'}}])
> -    inst = sniff_packets("lo", timeout=5)
>      pkt = Packet(pkt_type='UDP')
>      pkt.send_pkt(tx_port='lo')
> -    pkts = load_sniff_packets(inst)
> 
>      pkt = Packet(pkt_type='UDP', pkt_len=1500, ran_payload=True)
>      pkt.send_pkt(tx_port='lo')
> diff --git a/framework/tester.py b/framework/tester.py index
> a775f68..4e651a1 100755
> --- a/framework/tester.py
> +++ b/framework/tester.py
> @@ -35,6 +35,7 @@ Interface for bulk traffic generators.
> 
>  import re
>  import subprocess
> +import os
>  from time import sleep
>  from settings import NICS, load_global_setting, PERF_SETTING  from crb
> import Crb @@ -560,8 +561,6 @@ class Tester(Crb):
>          module = __import__("packet")
>          pkt_c = getattr(module, "Packet")
>          send_f = getattr(module, "send_packets")
> -        sniff_f = getattr(module, "sniff_packets")
> -        load_f = getattr(module, "load_sniff_packets")
>          compare_f = getattr(module, "compare_pktload")
>          strip_f = getattr(module, "strip_pktload")
>          save_f = getattr(module, "save_packets") @@ -606,7 +605,7 @@
> class Tester(Crb):
> 
>              # send and sniff packets
>              save_f(pkts=pkts, filename="/tmp/%s_tx.pcap" % txIntf)
> -            inst = sniff_f(intf=rxIntf, count=pktnum, timeout=timeout,
> filters=
> +            inst = self.tcpdump_sniff_packets(intf=rxIntf,
> + count=pktnum, timeout=timeout, filters=
>                  [{'layer': 'network', 'config': {'srcport': '65535'}},
>                   {'layer': 'network', 'config': {'dstport': '65535'}}])
>              rx_inst[rxport] = inst
> @@ -627,7 +626,7 @@ class Tester(Crb):
>          # Verify all packets
>          prev_id = -1
>          for txport, rxport in portList:
> -            recv_pkts = load_f(rx_inst[rxport])
> +            recv_pkts =
> + self.load_tcpdump_sniff_packets(rx_inst[rxport])
> 
>              # only report when recevied number not matched
>              if len(tx_pkts[txport]) > len(recv_pkts):
> @@ -704,6 +703,47 @@ class Tester(Crb):
>              self.proc.kill()
>              self.proc = None
> 
> +    def tcpdump_sniff_packets(self, intf, count=0, timeout=5, filters=[]):
> +        """
> +        Wrapper for packet module sniff_packets
> +        """
> +        # load functions in packet module
> +        module = __import__("packet")
> +        sniff_f = getattr(module, "sniff_packets")
> +
> +        target=[]
> +        target.append(self.get_ip_address())
> +        target.append(self.get_username())
> +        target.append(self.get_password())
> +        return sniff_f(intf, count, timeout, filters, target)
> +
> +    def load_tcpdump_sniff_pcap(self, index=''):
> +        """
> +        Wrapper for packet module load_sniff_pcap
> +        """
> +        # load functions in packet module
> +        module = __import__("packet")
> +        load_pcap_f = getattr(module, "load_sniff_pcap")
> +
> +        target=[]
> +        target.append(self.get_ip_address())
> +        target.append(self.get_username())
> +        target.append(self.get_password())
> +        pcap = load_pcap_f(index, target)
> +        self.session.copy_file_from(pcap)
> +
> +        return pcap.split(os.sep)[-1]
> +
> +    def load_tcpdump_sniff_packets(self, index=''):
> +        """
> +        Wrapper for packet module load_pcapfile
> +        """
> +        # load functions in packet module
> +        packet = __import__("packet")
> +        file = self.load_tcpdump_sniff_pcap(index)
> +
> +        return packet.load_pcapfile(file)
> +
>      def kill_all(self, killall=False):
>          """
>          Kill all scapy process or DPDK application on tester.
> --
> 2.7.4