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Feature pipe captures #280

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2 changes: 2 additions & 0 deletions src/pyshark/__init__.py
Original file line number Diff line number Diff line change
Expand Up @@ -14,3 +14,5 @@ class UnsupportedVersionException(Exception):
from pyshark.capture.file_capture import FileCapture
from pyshark.capture.remote_capture import RemoteCapture
from pyshark.capture.inmem_capture import InMemCapture
from pyshark.capture.pipe_capture import PipeCapture
from pyshark.capture.pipe_ring_capture import PipeRingCapture
4 changes: 2 additions & 2 deletions src/pyshark/capture/live_ring_capture.py
Original file line number Diff line number Diff line change
Expand Up @@ -8,7 +8,7 @@ class LiveRingCapture(LiveCapture):
def __init__(self, ring_file_size=1024, num_ring_files=1, ring_file_name='/tmp/pyshark.pcap', interface=None,
bpf_filter=None, display_filter=None, only_summaries=False, decryption_key=None,
encryption_type='wpa-pwk', decode_as=None, disable_protocol=None,
tshark_path=None, override_prefs=None, include_raw=False):
tshark_path=None, override_prefs=None, include_raw=False, use_json=False):
"""
Creates a new live capturer on a given interface. Does not start the actual capture itself.
:param ring_file_size: Size of the ring file in kB, default is 1024
Expand All @@ -31,7 +31,7 @@ def __init__(self, ring_file_size=1024, num_ring_files=1, ring_file_name='/tmp/p
super(LiveRingCapture, self).__init__(interface, bpf_filter=bpf_filter, display_filter=display_filter, only_summaries=only_summaries,
decryption_key=decryption_key, encryption_type=encryption_type,
tshark_path=tshark_path, decode_as=decode_as, disable_protocol=disable_protocol,
override_prefs=override_prefs, include_raw=include_raw)
override_prefs=override_prefs, include_raw=include_raw, use_json=use_json)

self.ring_file_size = ring_file_size
self.num_ring_files = num_ring_files
Expand Down
33 changes: 21 additions & 12 deletions src/pyshark/capture/pipe_capture.py
Original file line number Diff line number Diff line change
@@ -1,6 +1,3 @@
import trollius as asyncio
from trollius import From, Return

from pyshark.capture.capture import Capture


Expand Down Expand Up @@ -39,16 +36,28 @@ def get_parameters(self, packet_count=None):
Returns the special tshark parameters to be used according to the configuration of this class.
"""
params = super(PipeCapture, self).get_parameters(packet_count=packet_count)
params += ['-r', '-']
return params

@asyncio.coroutine
def _get_tshark_process(self, packet_count=None):
proc = yield From(super(PipeCapture, self)._get_tshark_process(packet_count=packet_count,
stdin=self._pipe))
raise Return(proc)
params.extend(['-i{}'.format(self._pipe), '-'])
return params[:-1]

def close(self):
# Close pipe
self._pipe.close()
# self._pipe.close() # Don't close the pipe. This should be the job of whatever is piping into it.
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That's fine, but remove this line entirely and add this to the class doc in CAPS or otherwise in an obvious manner

super(PipeCapture, self).close()

# Backwards compatibility
sniff = Capture.load_packets

def sniff_continuously(self, packet_count=None):
"""
Captures from the set interface, returning a generator which returns packets continuously.

Can be used as follows:
for packet in capture.sniff_continuously();
print 'Woo, another packet:', packet

Note: you can also call capture.apply_on_packets(packet_callback) which should have a slight performance boost.

:param packet_count: an amount of packets to capture, then stop.
"""
# Retained for backwards compatibility and to add documentation.
return self._packets_from_tshark_sync(packet_count=packet_count)
64 changes: 64 additions & 0 deletions src/pyshark/capture/pipe_ring_capture.py
Original file line number Diff line number Diff line change
@@ -0,0 +1,64 @@
from pyshark.capture.pipe_capture import PipeCapture
from pyshark.capture.capture import TSharkCrashException, TSharkVersionException
from pyshark.tshark.tshark import tshark_supports_json
import asyncio
import subprocess
import tempfile


class DisplayFilterNotAllowedException(Exception):
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Due to how RingCaptures work, Tshark will not allow a display filter in this class.

"""Display Filters are not allowed in PipeRingCapture."""


class PipeRingCapture(PipeCapture):
"""
Represents a live ringbuffer capture on a network interface.
"""

def __init__(self, pipe, ring_file_size=1024, num_ring_files=2, ring_file_name=None,
display_filter=None, only_summaries=False, decryption_key=None,
encryption_type='wpa-pwk', decode_as=None, disable_protocol=None,
tshark_path=None, override_prefs=None, include_raw=False, use_json=False):
"""
Creates a new live capturer on a given interface. Does not start the actual capture itself.
:param ring_file_size: Size of the ring file in kB, default is 1024
:param num_ring_files: Number of ring files to keep, default is 1
:param ring_file_name: Name of the ring file, default is /tmp/pyshark.pcap
:param interface: Name of the interface to sniff on or a list of names (str). If not given, runs on all interfaces.
:param bpf_filter: BPF filter to use on packets.
:param display_filter: Display (wireshark) filter to use.
:param only_summaries: Only produce packet summaries, much faster but includes very little information
:param decryption_key: Optional key used to encrypt and decrypt captured traffic.
:param encryption_type: Standard of encryption used in captured traffic (must be either 'WEP', 'WPA-PWD', or
'WPA-PWK'. Defaults to WPA-PWK).
:param decode_as: A dictionary of {decode_criterion_string: decode_as_protocol} that are used to tell tshark
to decode protocols in situations it wouldn't usually, for instance {'tcp.port==8888': 'http'} would make
it attempt to decode any port 8888 traffic as HTTP. See tshark documentation for details.
:param tshark_path: Path of the tshark binary
:param override_prefs: A dictionary of tshark preferences to override, {PREFERENCE_NAME: PREFERENCE_VALUE, ...}.
:param disable_protocol: Tells tshark to remove a dissector for a specifc protocol.
"""
if display_filter is not None:
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It's possible simply not to have it as a parameter in the init and just to write it in the doc. This is a bit more explicit so I'm not 100% about it.

raise DisplayFilterNotAllowedException("Display Filters are not allowed in PipeRingCapture.")

super(PipeRingCapture, self).__init__(pipe, display_filter=display_filter, only_summaries=only_summaries,
decryption_key=decryption_key, encryption_type=encryption_type,
tshark_path=tshark_path, decode_as=decode_as, disable_protocol=disable_protocol,
override_prefs=override_prefs, include_raw=include_raw, use_json=use_json)

self.ring_file_size = ring_file_size
self.num_ring_files = num_ring_files
if ring_file_name is None:
self.ring_file_name = tempfile.mktemp(suffix=".pcap", prefix="pyshark_")
else:
self.ring_file_name = ring_file_name

def get_parameters(self, packet_count=None):
"""
Returns the special tshark parameters to be used according to the configuration of this class.
"""
params = super(PipeRingCapture, self).get_parameters()[:-2]
params.extend(['-i', self._pipe])
params += ['-b', 'filesize:' + str(self.ring_file_size), '-b', 'files:' + str(self.num_ring_files), '-w',
self.ring_file_name, '-P']
return params