scapy.sendrecv module

Functions to send and receive packets.

class scapy.sendrecv.AsyncSniffer(*args: Any, **kwargs: Any)[source]

Bases: object

Sniff packets and return a list of packets.

Parameters:

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: prn = lambda x: x.summary()
session – a session = a flow decoder used to handle stream of packets. –Ex: session=TCPSession See below for more details.
filter – BPF filter to apply.
lfilter – Python function applied to each packet to determine if further action may be done. –Ex: lfilter = lambda x: x.haslayer(Padding)
offline – PCAP file (or list of PCAP files) to read packets from, instead of sniffing them
quiet – when set to True, the process stderr is discarded (default: False).
timeout – stop sniffing after a given time (default: None).
L2socket – use the provided L2socket (default: use conf.L2listen).
opened_socket – provide an object (or a list of objects) ready to use .recv() on.
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)
iface – interface or list of interfaces (default: None for sniffing on the default interface).
monitor – use monitor mode. May not be available on all OS
started_callback – called as soon as the sniffer starts sniffing (default: None).

The iface, offline and opened_socket parameters can be either an element, a list of elements, or a dict object mapping an element to a label (see examples below).

For more information about the session argument, see https://scapy.rtfd.io/en/latest/usage.html#advanced-sniffing-sniffing-sessions

Examples: synchronous

>>> sniff(filter="arp")
>>> sniff(filter="tcp",
...       session=IPSession,  # defragment on-the-flow
...       prn=lambda x: x.summary())
>>> sniff(lfilter=lambda pkt: ARP in pkt)
>>> sniff(iface="eth0", prn=Packet.summary)
>>> sniff(iface=["eth0", "mon0"],
...       prn=lambda pkt: "%s: %s" % (pkt.sniffed_on,
...                                   pkt.summary()))
>>> sniff(iface={"eth0": "Ethernet", "mon0": "Wifi"},
...       prn=lambda pkt: "%s: %s" % (pkt.sniffed_on,
...                                   pkt.summary()))

Examples: asynchronous

>>> t = AsyncSniffer(iface="enp0s3")
>>> t.start()
>>> time.sleep(1)
>>> print("nice weather today")
>>> t.stop()

join(*args: Any, **kwargs: Any) → None[source]

start() → None[source]: Starts AsyncSniffer in async mode

stop(join: bool = True) → PacketList | None[source]: Stops AsyncSniffer if not in async mode

class scapy.sendrecv.SndRcvHandler(pks: SuperSocket, pkt: Sequence[Packet] | Packet | SetGen[Packet] | _PacketList[Packet], timeout: int | None = None, inter: int = 0, verbose: int | None = None, chainCC: bool = False, retry: int = 0, multi: bool = False, rcv_pks: SuperSocket | None = None, prebuild: bool = False, _flood: _FloodGenerator | None = None, threaded: bool = True, session: Type[DefaultSession] | DefaultSession | None = None, chainEX: bool = False, stop_filter: Callable[[Packet], bool] | None = None)[source]

Bases: object

Util to send/receive packets, used by sr*(). Do not use directly.

This matches the requests and answers.

Notes::

threaded: if you’re planning to send/receive many packets, it’s likely a good idea to use threaded mode.
DEVS: store the outgoing timestamp right BEFORE sending the packet to avoid races that could result in negative latency. We aren’t Stadia

results() → Tuple[SndRcvList, PacketList][source]

Forward traffic between interfaces if1 and if2, sniff and return the exchanged packets.

Parameters:

if1 – the interfaces to use (interface names or opened sockets).
if2
xfrm12 – a function to call when forwarding a packet from if1 to if2. If it returns True, the packet is forwarded as it. If it returns False or None, the packet is discarded. If it returns a packet, this packet is forwarded instead of the original packet one.
xfrm21 – same as xfrm12 for packets forwarded from if2 to if1.

The other arguments are the same than for the function sniff(), except for offline, opened_socket and iface that are ignored. See help(sniff) for more.

class scapy.sendrecv.debug[source]

Bases: object

crashed_on: Tuple[Type[Packet], bytes] | None = None

match = <Matched: TCP:0 UDP:0 ICMP:0 Other:0>

recv = <Received: TCP:0 UDP:0 ICMP:0 Other:0>

sent = <Sent: TCP:0 UDP:0 ICMP:0 Other:0>

scapy.sendrecv.send(x: Sequence[Packet] | Packet | SetGen[Packet] | _PacketList[Packet], **kargs: Any) → PacketList | None[source]

Send packets at layer 3

This determines the interface (or L2 source to use) based on the routing table: conf.route / conf.route6

Parameters:

x – the packets
inter – time (in s) between two packets (default 0)
loop – send packet indefinitely (default 0)
count – number of packets to send (default None=1)
verbose – verbose mode (default None=conf.verb)
realtime – check that a packet was sent before sending the next one
return_packets – return the sent packets
socket – the socket to use (default is conf.L3socket(kargs))
monitor – (not on linux) send in monitor mode

Returns:

None

Send packets at layer 2

Parameters:

x – the packets
inter – time (in s) between two packets (default 0)
loop – send packet indefinitely (default 0)
count – number of packets to send (default None=1)
verbose – verbose mode (default None=conf.verb)
realtime – check that a packet was sent before sending the next one
return_packets – return the sent packets
socket – the socket to use (default is conf.L3socket(kargs))
iface – the interface to send the packets on
monitor – (not on linux) send in monitor mode

Returns:

None

Send packets at layer 2 using tcpreplay for performance

Parameters:

pps – packets per second
mbps – MBits per second
realtime – use packet’s timestamp, bending time with real-time value
loop – send the packet indefinitely (default 0)
count – number of packets to send (default None=1)
file_cache – cache packets in RAM instead of reading from disk at each iteration
iface – output interface
replay_args – List of additional tcpreplay args (List[str])
parse_results – Return a dictionary of information outputted by tcpreplay (default=False)

Returns:

stdout, stderr, command used

scapy.sendrecv.sndrcv(*args: Any, **kwargs: Any) → Tuple[SndRcvList, PacketList][source]: Scapy raw function to send a packet and receive its answer. WARNING: This is an internal function. Using sr/srp/sr1/srp is more appropriate in many cases.

scapy.sendrecv.sndrcvflood(pks: SuperSocket, pkt: Sequence[Packet] | Packet | SetGen[Packet] | _PacketList[Packet], inter: int = 0, maxretries: int | None = None, verbose: int | None = None, chainCC: bool = False, timeout: int | None = None) → Tuple[SndRcvList, PacketList][source]: sndrcv equivalent for flooding.

scapy.sendrecv.sniff(*args: Any, **kwargs: Any) → PacketList[source]

Sniff packets and return a list of packets.

Parameters:

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: prn = lambda x: x.summary()
session – a session = a flow decoder used to handle stream of packets. –Ex: session=TCPSession See below for more details.
filter – BPF filter to apply.
lfilter – Python function applied to each packet to determine if further action may be done. –Ex: lfilter = lambda x: x.haslayer(Padding)
offline – PCAP file (or list of PCAP files) to read packets from, instead of sniffing them
quiet – when set to True, the process stderr is discarded (default: False).
timeout – stop sniffing after a given time (default: None).
L2socket – use the provided L2socket (default: use conf.L2listen).
opened_socket – provide an object (or a list of objects) ready to use .recv() on.
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)
iface – interface or list of interfaces (default: None for sniffing on the default interface).
monitor – use monitor mode. May not be available on all OS
started_callback – called as soon as the sniffer starts sniffing (default: None).

The iface, offline and opened_socket parameters can be either an element, a list of elements, or a dict object mapping an element to a label (see examples below).

For more information about the session argument, see https://scapy.rtfd.io/en/latest/usage.html#advanced-sniffing-sniffing-sessions

Examples: synchronous

>>> sniff(filter="arp")
>>> sniff(filter="tcp",
...       session=IPSession,  # defragment on-the-flow
...       prn=lambda x: x.summary())
>>> sniff(lfilter=lambda pkt: ARP in pkt)
>>> sniff(iface="eth0", prn=Packet.summary)
>>> sniff(iface=["eth0", "mon0"],
...       prn=lambda pkt: "%s: %s" % (pkt.sniffed_on,
...                                   pkt.summary()))
>>> sniff(iface={"eth0": "Ethernet", "mon0": "Wifi"},
...       prn=lambda pkt: "%s: %s" % (pkt.sniffed_on,
...                                   pkt.summary()))

Examples: asynchronous

>>> t = AsyncSniffer(iface="enp0s3")
>>> t.start()
>>> time.sleep(1)
>>> print("nice weather today")
>>> t.stop()

Send and receive packets at layer 3

This determines the interface (or L2 source to use) based on the routing table: conf.route / conf.route6

Parameters:

pks – SuperSocket instance to send/receive packets
pkt – the packet to send
timeout – how much time to wait after the last packet has been sent
inter – delay between two packets during sending
verbose – set verbosity level
chainCC – if True, KeyboardInterrupts will be forwarded
retry – if positive, how many times to resend unanswered packets if negative, how many times to retry when no more packets are answered
multi – whether to accept multiple answers for the same stimulus
rcv_pks – if set, will be used instead of pks to receive packets. packets will still be sent through pks
prebuild – pre-build the packets before starting to send them. Automatically enabled when a generator is passed as the packet
_flood
threaded – if True, packets are sent in a thread and received in another. Defaults to True.
session – a flow decoder used to handle stream of packets
chainEX – if True, exceptions during send will be forwarded
stop_filter – Python function applied to each packet to determine if we have to stop the capture after this packet.

scapy.sendrecv.sr1(*args: Any, **kargs: Any) → Packet | None[source]

Send packets at layer 3 and return only the first answer

This determines the interface (or L2 source to use) based on the routing table: conf.route / conf.route6

Parameters:

pks – SuperSocket instance to send/receive packets
pkt – the packet to send
timeout – how much time to wait after the last packet has been sent
inter – delay between two packets during sending
verbose – set verbosity level
chainCC – if True, KeyboardInterrupts will be forwarded
retry – if positive, how many times to resend unanswered packets if negative, how many times to retry when no more packets are answered
multi – whether to accept multiple answers for the same stimulus
rcv_pks – if set, will be used instead of pks to receive packets. packets will still be sent through pks
prebuild – pre-build the packets before starting to send them. Automatically enabled when a generator is passed as the packet
_flood
threaded – if True, packets are sent in a thread and received in another. Defaults to True.
session – a flow decoder used to handle stream of packets
chainEX – if True, exceptions during send will be forwarded
stop_filter – Python function applied to each packet to determine if we have to stop the capture after this packet.

Flood and receive packets at layer 3 and return only the first answer

This determines the interface (or L2 source to use) based on the routing table: conf.route / conf.route6

Parameters:

prn – function applied to packets received
verbose – set verbosity level
nofilter – put 1 to avoid use of BPF filters
filter – provide a BPF filter
iface – listen answers only on the given interface

scapy.sendrecv.sr_func(*args: Any, **kargs: Any) → Packet | None[source]

Send packets at layer 3 and return only the first answer

This determines the interface (or L2 source to use) based on the routing table: conf.route / conf.route6

Parameters:

pks – SuperSocket instance to send/receive packets
pkt – the packet to send
timeout – how much time to wait after the last packet has been sent
inter – delay between two packets during sending
verbose – set verbosity level
chainCC – if True, KeyboardInterrupts will be forwarded
retry – if positive, how many times to resend unanswered packets if negative, how many times to retry when no more packets are answered
multi – whether to accept multiple answers for the same stimulus
rcv_pks – if set, will be used instead of pks to receive packets. packets will still be sent through pks
prebuild – pre-build the packets before starting to send them. Automatically enabled when a generator is passed as the packet
_flood
threaded – if True, packets are sent in a thread and received in another. Defaults to True.
session – a flow decoder used to handle stream of packets
chainEX – if True, exceptions during send will be forwarded
stop_filter – Python function applied to each packet to determine if we have to stop the capture after this packet.

Flood and receive packets at layer 3

This determines the interface (or L2 source to use) based on the routing table: conf.route / conf.route6

Parameters:

prn – function applied to packets received
unique – only consider packets whose print
nofilter – put 1 to avoid use of BPF filters
filter – provide a BPF filter

scapy.sendrecv.srloop(pkts: Sequence[Packet] | Packet | SetGen[Packet] | _PacketList[Packet], *args: Any, **kargs: Any) → Tuple[SndRcvList, PacketList][source]: Send a packet at layer 3 in loop and print the answer each time srloop(pkts, [prn], [inter], [count], …) –> None

Send and receive packets at layer 2

Parameters:

pks – SuperSocket instance to send/receive packets
pkt – the packet to send
timeout – how much time to wait after the last packet has been sent
inter – delay between two packets during sending
verbose – set verbosity level
chainCC – if True, KeyboardInterrupts will be forwarded
retry – if positive, how many times to resend unanswered packets if negative, how many times to retry when no more packets are answered
multi – whether to accept multiple answers for the same stimulus
rcv_pks – if set, will be used instead of pks to receive packets. packets will still be sent through pks
prebuild – pre-build the packets before starting to send them. Automatically enabled when a generator is passed as the packet
_flood
threaded – if True, packets are sent in a thread and received in another. Defaults to True.
session – a flow decoder used to handle stream of packets
chainEX – if True, exceptions during send will be forwarded
stop_filter – Python function applied to each packet to determine if we have to stop the capture after this packet.

scapy.sendrecv.srp1(*args: Any, **kargs: Any) → Packet | None[source]

Send and receive packets at layer 2 and return only the first answer

Parameters:

pks – SuperSocket instance to send/receive packets
pkt – the packet to send
timeout – how much time to wait after the last packet has been sent
inter – delay between two packets during sending
verbose – set verbosity level
chainCC – if True, KeyboardInterrupts will be forwarded
retry – if positive, how many times to resend unanswered packets if negative, how many times to retry when no more packets are answered
multi – whether to accept multiple answers for the same stimulus
rcv_pks – if set, will be used instead of pks to receive packets. packets will still be sent through pks
prebuild – pre-build the packets before starting to send them. Automatically enabled when a generator is passed as the packet
_flood
threaded – if True, packets are sent in a thread and received in another. Defaults to True.
session – a flow decoder used to handle stream of packets
chainEX – if True, exceptions during send will be forwarded
stop_filter – Python function applied to each packet to determine if we have to stop the capture after this packet.

Flood and receive packets at layer 2 and return only the first answer

Parameters:

prn – function applied to packets received
verbose – set verbosity level
nofilter – put 1 to avoid use of BPF filters
filter – provide a BPF filter
iface – listen answers only on the given interface

Flood and receive packets at layer 2

Parameters:

prn – function applied to packets received
unique – only consider packets whose print
nofilter – put 1 to avoid use of BPF filters
filter – provide a BPF filter
iface – listen answers only on the given interface

scapy.sendrecv.srploop(pkts: Sequence[Packet] | Packet | SetGen[Packet] | _PacketList[Packet], *args: Any, **kargs: Any) → Tuple[SndRcvList, PacketList][source]: Send a packet at layer 2 in loop and print the answer each time srloop(pkts, [prn], [inter], [count], …) –> None

scapy.sendrecv.tshark(*args: Any, **kargs: Any) → None[source]: Sniff packets and print them calling pkt.summary(). This tries to replicate what text-wireshark (tshark) would look like