From d5e3fc20994f338358a18b33bd8818c75bf1484b Mon Sep 17 00:00:00 2001
From: Pierre LALET <pierre.lalet@cea.fr>
Date: Fri, 25 Aug 2017 13:49:52 +0200
Subject: [PATCH] Implement bridge_and_sniff() using sniff()
This removes duplicated code and should make bridge_and_sniff()
function work under Windows.
---
scapy/sendrecv.py | 100 +++++++++++++++++-----------------------------
1 file changed, 36 insertions(+), 64 deletions(-)
diff --git a/scapy/sendrecv.py b/scapy/sendrecv.py
index dee5a746..4503abca 100644
--- a/scapy/sendrecv.py
+++ b/scapy/sendrecv.py
@@ -734,76 +734,48 @@ Examples:
@conf.commands.register
-def bridge_and_sniff(if1, if2, count=0, store=1, prn=None, lfilter=None,
- L2socket=None, timeout=None, stop_filter=None, *args,
- **kargs):
- """Forward traffic between two interfaces and sniff packets exchanged
-bridge_and_sniff([count=0,] [prn=None,] [store=1,] [offline=None,]
-[lfilter=None,] + L2Socket args) -> list of packets
-
- count: number of packets to capture. 0 means infinity
- store: whether to store sniffed packets or discard them
- prn: function to apply to each packet. If something is returned,
- it is displayed. Ex:
- ex: prn = lambda x: x.summary()
-lfilter: python function applied to each packet to determine
- if further action may be done
- ex: lfilter = lambda x: x.haslayer(Padding)
-timeout: stop sniffing after a given time (default: None)
-L2socket: use the provided L2socket
-stop_filter: python function applied to each packet to determine
- if we have to stop the capture after this packet
- ex: stop_filter = lambda x: x.haslayer(TCP)
+def bridge_and_sniff(if1, if2, prn=None, L2socket=None, *args, **kargs):
+ """Forward traffic between interfaces if1 and if2, sniff and return the
+exchanged packets.
+
+Arguments:
+
+ if1, if2: the interfaces to use
+
+ The other arguments are the same than for the function sniff(),
+ except for opened_socket, offline and iface that are ignored.
+ See help(sniff) for more.
+
"""
- c = 0
+ for arg in ['opened_socket', 'offline', 'iface']:
+ if arg in kargs:
+ log_runtime.warning("Argument %s cannot be used in "
+ "bridge_and_sniff() -- ignoring it.", arg)
+ del kargs[arg]
if L2socket is None:
L2socket = conf.L2socket
s1 = L2socket(iface=if1)
s2 = L2socket(iface=if2)
- peerof={s1:s2,s2:s1}
- label={s1:if1, s2:if2}
-
- lst = []
- if timeout is not None:
- stoptime = time.time()+timeout
- remain = None
- try:
- stop_event = False
- while not stop_event:
- if timeout is not None:
- remain = stoptime-time.time()
- if remain <= 0:
- break
- if conf.use_bpf:
- from scapy.arch.bpf.supersocket import bpf_select
- ins = bpf_select([s1, s2], remain)
- else:
- ins, _, _ = select([s1, s2], [], [], remain)
+ peers = {if1: s2, if2: s1}
+ def prn_send(pkt):
+ try:
+ sendsock = peers[pkt.sniffed_on]
+ except KeyError:
+ return
+ try:
+ sendsock.send(pkt.original)
+ except:
+ log_runtime.warning('Cannot forward packet [%s] received from %s',
+ pkt.summary(), pkt.sniffed_on, exc_info=True)
+ if prn is None:
+ prn = prn_send
+ else:
+ prn_orig = prn
+ def prn(pkt):
+ prn_send(pkt)
+ return prn_orig(pkt)
- for s in ins:
- p = s.recv()
- if p is not None:
- peerof[s].send(p.original)
- if lfilter and not lfilter(p):
- continue
- if store:
- p.sniffed_on = label[s]
- lst.append(p)
- c += 1
- if prn:
- r = prn(p)
- if r is not None:
- print(r)
- if stop_filter and stop_filter(p):
- stop_event = True
- break
- if 0 < count <= c:
- stop_event = True
- break
- except KeyboardInterrupt:
- pass
- finally:
- return plist.PacketList(lst,"Sniffed")
+ return sniff(opened_socket={s1: if1, s2: if2}, prn=prn, *args, **kargs)
@conf.commands.register
--
GitLab