Re: [dts] [PATCH 01/17] framwork/packet: Add sniff_packet specify running

[Phil Yang <Phil.Yang@arm.com>]

Hi Marvin,

> -----Original Message-----
> From: Liu, Yong <yong.liu@intel.com>
> Sent: Wednesday, March 28, 2018 10:41 AM
> To: Phil Yang <Phil.Yang@arm.com>; dts@dpdk.org
> Cc: nd <nd@arm.com>; Herbert Guan <Herbert.Guan@arm.com>
> Subject: RE: [PATCH 01/17] framwork/packet: Add sniff_packet specify running
> 
> Hi Phil,
> In previous design, DTS will be run on tester for simple design and stability.
> In our site, I can't see the benefit of change the design. Could you please explain
> why you change it?
> Anyway we can change the design, but I think it will need some kind of diagnosis
> about the impact.
> There may be some other staff depend on the assumption that DTS is on the
> tester machine.


We are trying to use one machine as the controller to run DTS. The controller communicate with testers which listed in the crbs.cfg by SSH connection.
So the DTS will not running on tester. 

Since testers are connected with DUTs port by port, so I think introduce controller into the DTS is more flexible to manager machines. If other staff depend on the assumption that DTS is no the tester machine, sniff_packet process will also connect to the tester by SSH connection. Just one more SSH connection.
However, we cannot make sure the DTS is always running on the tester. 


> 
> Just for this patch. In load function, DTS machine should transmit tester's pcap
> file first and then analyze packets.

You are correct. Thanks to point out.

If my proposal is acceptable, I will resend the version 2 to add the transmit process.

Thanks.

> 
> Regards,
> Marvin
> 
> > -----Original Message-----
> > From: Phil Yang [mailto:phil.yang@arm.com]
> > Sent: Friday, March 23, 2018 4:04 PM
> > To: dts@dpdk.org
> > Cc: nd@arm.com; phil.yang@arm.com; Liu, Yong <yong.liu@intel.com>;
> > herbert.guan@arm.com
> > Subject: [PATCH 01/17] framwork/packet: Add sniff_packet specify
> > running
> >
> > If tester in crb file was not the machine which running dts, the
> > sniff_packet process will not running on tester.
> >
> > Create a ssh connection to the tester and run tcpdump to make sure
> > sniff_packet process running on the machine we expected.
> >
> > Signed-off-by: Phil Yang <phil.yang@arm.com>
> > ---
> >  framework/packet.py | 34 ++++++++++++++++++++++++++++------
> >  framework/tester.py | 34 ++++++++++++++++++++++++++++++++++
> >  2 files changed, 62 insertions(+), 6 deletions(-)
> >
> > diff --git a/framework/packet.py b/framework/packet.py index
> > 976b82b..484e511 100755
> > --- a/framework/packet.py
> > +++ b/framework/packet.py
> > @@ -812,15 +812,30 @@ 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)
> > +
> > +    # target[] contain the remote machine info for ssh connection
> > +    # target[0]: username
> > +    # target[1]: ip address
> > +    # target[2]: pass word
> > +    if target:
> > +        tcpdump_help_pipe = subprocess.Popen(["ssh",
> > +                            "%s@%s" % (target[0], target[1]),
> > +                            "tcpdump -h"],
> > +                            stderr=subprocess.PIPE,
> > +                            stdout=subprocess.PIPE,
> > +                            shell=False)
> > +        tcpdump_help = "".join(tuple(tcpdump_help_pipe.communicate()))
> > +        tcpdump_help_pipe.wait()
> > +    else:
> > +        tcpdump_help = subprocess.check_output("tcpdump -h; echo 0",
> > +                                    stderr=subprocess.STDOUT,
> > + shell=True)
> > +
> >      for line in tcpdump_help.split('\n'):
> >          m = re.match(direct_param, line)
> >          if m:
> > @@ -850,9 +865,16 @@ def sniff_packets(intf, count=0, timeout=5,
> > filters=[]):
> >      else:
> >          cmd = sniff_cmd % options
> >
> > -    args = shlex.split(cmd)
> > +    if target:
> > +        pipe = subprocess.Popen(["ssh",
> > +                "%s@%s" % (target[0], target[1]),
> > +                cmd],
> > +                stdin=subprocess.PIPE,
> > +                shell=False)
> > +    else:
> > +        args = shlex.split(cmd)
> > +        pipe = subprocess.Popen(args)
> >
> > -    pipe = subprocess.Popen(args)
> >      index = str(time.time())
> >      SNIFF_PIDS[index] = (pipe, intf, timeout)
> >      time.sleep(1)
> > diff --git a/framework/tester.py b/framework/tester.py index
> > a775f68..49749de 100755
> > --- a/framework/tester.py
> > +++ b/framework/tester.py
> > @@ -704,6 +704,40 @@ 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_username())
> > +        target.append(self.get_ip_address())
> > +        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")
> > +
> > +        return load_pcap_f(index)
> > +
> > +    def load_tcpdump_sniff_packets(self, index=''):
> > +        """
> > +        Wrapper for packet module load_sniff_packets
> > +        """
> > +        # load functions in packet module
> > +        module = __import__("packet")
> > +        load_f = getattr(module, "load_sniff_packets")
> > +
> > +        return load_f(index)
> > +
> >      def kill_all(self, killall=False):
> >          """
> >          Kill all scapy process or DPDK application on tester.
> > --
> > 2.7.4