X-Git-Url: https://gerrit.fd.io/r/gitweb?a=blobdiff_plain;f=resources%2Flibraries%2Fpython%2FPacketVerifier.py;h=fb2337e49d1718c104cc94ce45ed43dc71f40cb9;hb=16ef90a2415aa3b65341fdb6517cf58721bfff7a;hp=59ea2db5a30e68c1845d5fed59839504e9f416ca;hpb=f2711a847cd8de8dadce1049747e78f96bcae031;p=csit.git diff --git a/resources/libraries/python/PacketVerifier.py b/resources/libraries/python/PacketVerifier.py index 59ea2db5a3..fb2337e49d 100644 --- a/resources/libraries/python/PacketVerifier.py +++ b/resources/libraries/python/PacketVerifier.py @@ -1,4 +1,4 @@ -# Copyright (c) 2016 Cisco and/or its affiliates. +# Copyright (c) 2019 Cisco and/or its affiliates. # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at: @@ -13,79 +13,86 @@ """PacketVerifier module. - :Example: - - >>> from scapy.all import * - >>> from PacketVerifier import * - >>> rxq = RxQueue('eth1') - >>> txq = TxQueue('eth1') - >>> src_mac = "AA:BB:CC:DD:EE:FF" - >>> dst_mac = "52:54:00:ca:5d:0b" - >>> src_ip = "11.11.11.10" - >>> dst_ip = "11.11.11.11" - >>> sent_packets = [] - >>> pkt_send = Ether(src=src_mac, dst=dst_mac) / - ... IP(src=src_ip, dst=dst_ip) / - ... ICMP() - >>> sent_packets.append(pkt_send) - >>> txq.send(pkt_send) - >>> pkt_send = Ether(src=src_mac, dst=dst_mac) / - ... ARP(hwsrc=src_mac, psrc=src_ip, hwdst=dst_mac, pdst=dst_ip, op=2) - >>> sent_packets.append(pkt_send) - >>> txq.send(pkt_send) - >>> rxq.recv(100, sent_packets).show() - ###[ Ethernet ]### - dst = aa:bb:cc:dd:ee:ff - src = 52:54:00:ca:5d:0b - type = 0x800 - ###[ IP ]### - version = 4L - ihl = 5L - tos = 0x0 - len = 28 - id = 43183 - flags = - frag = 0L - ttl = 64 - proto = icmp - chksum = 0xa607 - src = 11.11.11.11 - dst = 11.11.11.10 - \options \ - ###[ ICMP ]### - type = echo-reply - code = 0 - chksum = 0xffff - id = 0x0 - seq = 0x0 - ###[ Padding ]### - load = 'RT\x00\xca]\x0b\xaa\xbb\xcc\xdd\xee\xff\x08\x06\x00\x01\x08\x00' + Example. :: + + | >>> from scapy.all import * + | >>> from PacketVerifier import * + | >>> rxq = RxQueue('eth1') + | >>> txq = TxQueue('eth1') + | >>> src_mac = "AA:BB:CC:DD:EE:FF" + | >>> dst_mac = "52:54:00:ca:5d:0b" + | >>> src_ip = "11.11.11.10" + | >>> dst_ip = "11.11.11.11" + | >>> sent_packets = [] + | >>> pkt_send = Ether(src=src_mac, dst=dst_mac) / + | ... IP(src=src_ip, dst=dst_ip) / + | ... ICMP() + | >>> sent_packets.append(pkt_send) + | >>> txq.send(pkt_send) + | >>> pkt_send = Ether(src=src_mac, dst=dst_mac) / + | ... ARP(hwsrc=src_mac, psrc=src_ip, hwdst=dst_mac, pdst=dst_ip, op=2) + | >>> sent_packets.append(pkt_send) + | >>> txq.send(pkt_send) + | >>> rxq.recv(100, sent_packets).show() + | ###[ Ethernet ]### + | dst = aa:bb:cc:dd:ee:ff + | src = 52:54:00:ca:5d:0b + | type = 0x800 + | ###[ IP ]### + | version = 4L + | ihl = 5L + | tos = 0x0 + | len = 28 + | id = 43183 + | flags = + | frag = 0L + | ttl = 64 + | proto = icmp + | chksum = 0xa607 + | src = 11.11.11.11 + | dst = 11.11.11.10 + | options + | ###[ ICMP ]### + | type = echo-reply + | code = 0 + | chksum = 0xffff + | id = 0x0 + | seq = 0x0 + | ###[ Padding ]### + | load = 'RT\x00\xca]\x0b\xaa\xbb\xcc\xdd\xee\xff\x08\x06\x00\x01\x08\x00' + + Example end. """ - import os -import socket import select from scapy.all import ETH_P_IP, ETH_P_IPV6, ETH_P_ALL, ETH_P_ARP -from scapy.all import Ether, ARP, Packet +from scapy.config import conf from scapy.layers.inet6 import IPv6 +from scapy.layers.l2 import Ether, ARP +from scapy.packet import Raw + +# Enable libpcap's L2listen +conf.use_pcap = True -__all__ = ['RxQueue', 'TxQueue', 'Interface', 'create_gratuitous_arp_request', - 'auto_pad', 'checksum_equal'] +__all__ = [ + u"RxQueue", u"TxQueue", u"Interface", u"create_gratuitous_arp_request", + u"auto_pad", u"checksum_equal" +] -# TODO: http://stackoverflow.com/questions/320232/ensuring-subprocesses-are-dead-on-exiting-python-program +# TODO: http://stackoverflow.com/questions/320232/ +# ensuring-subprocesses-are-dead-on-exiting-python-program -class PacketVerifier(object): +class PacketVerifier: """Base class for TX and RX queue objects for packet verifier.""" def __init__(self, interface_name): - os.system('sudo echo 1 > /proc/sys/net/ipv6/conf/{0}/disable_ipv6' - .format(interface_name)) - os.system('sudo ip link set {0} up promisc on'.format(interface_name)) - self._sock = socket.socket(socket.AF_PACKET, socket.SOCK_RAW, - ETH_P_ALL) - self._sock.bind((interface_name, ETH_P_ALL)) + os.system( + f"sudo echo 1 > /proc/sys/net/ipv6/conf/{interface_name}/" + f"disable_ipv6" + ) + os.system(f"sudo ip link set {interface_name} up promisc on") self._ifname = interface_name @@ -97,7 +104,7 @@ def extract_one_packet(buf): :param buf: String representation of incoming packet buffer. :type buf: str - :return: String representation of first packet in buf. + :returns: String representation of first packet in buf. :rtype: str """ pkt_len = 0 @@ -105,16 +112,10 @@ def extract_one_packet(buf): if len(buf) < 60: return None - # print - # print buf.__repr__() - # print Ether(buf).__repr__() - # print len(Ether(buf)) - # print try: ether_type = Ether(buf[0:14]).type except AttributeError: - raise RuntimeError( - 'No EtherType in packet {0}'.format(buf.__repr__())) + raise RuntimeError(f"No EtherType in packet {buf!r}") if ether_type == ETH_P_IP: # 14 is Ethernet fame header size. @@ -126,17 +127,16 @@ def extract_one_packet(buf): return None elif ether_type == ETH_P_IPV6: if not Ether(buf[0:14+6]).haslayer(IPv6): - raise RuntimeError( - 'Invalid IPv6 packet {0}'.format(buf.__repr__())) + raise RuntimeError(f"Invalid IPv6 packet {buf!r}") # ... to add to the above, 40 bytes is the length of IPV6 header. # The ipv6.len only contains length of the payload and not the header - pkt_len = Ether(buf)['IPv6'].plen + 14 + 40 + pkt_len = Ether(buf)[u"IPv6"].plen + 14 + 40 if len(buf) < 60: return None elif ether_type == ETH_P_ARP: pkt = Ether(buf[:20]) if not pkt.haslayer(ARP): - raise RuntimeError('Incomplete ARP packet') + raise RuntimeError(u"Incomplete ARP packet") # len(eth) + arp(2 hw addr type + 2 proto addr type # + 1b len + 1b len + 2b operation) @@ -148,10 +148,10 @@ def extract_one_packet(buf): elif ether_type == 32821: # RARP (Reverse ARP) pkt = Ether(buf[:20]) pkt.type = ETH_P_ARP # Change to ARP so it works with scapy - pkt = Ether(str(pkt)) + pkt = Ether(pkt) if not pkt.haslayer(ARP): pkt.show() - raise RuntimeError('Incomplete RARP packet') + raise RuntimeError(u"Incomplete RARP packet") # len(eth) + arp(2 hw addr type + 2 proto addr type # + 1b len + 1b len + 2b operation) @@ -161,7 +161,7 @@ def extract_one_packet(buf): del pkt else: - raise RuntimeError('Unknown protocol {0}'.format(ether_type)) + raise RuntimeError(f"Unknown protocol {ether_type}") if pkt_len < 60: pkt_len = 60 @@ -182,10 +182,8 @@ def packet_reader(interface_name, queue): :param queue: Queue in which this function will push incoming packets. :type interface_name: str :type queue: multiprocessing.Queue - :return: None """ - sock = socket.socket(socket.AF_PACKET, socket.SOCK_RAW, ETH_P_ALL) - sock.bind((interface_name, ETH_P_ALL)) + sock = conf.L2listen(iface=interface_name, type=ETH_P_ALL) while True: pkt = sock.recv(0x7fff) @@ -203,6 +201,7 @@ class RxQueue(PacketVerifier): """ def __init__(self, interface_name): PacketVerifier.__init__(self, interface_name) + self._sock = conf.L2listen(iface=interface_name, type=ETH_P_ALL) def recv(self, timeout=3, ignore=None, verbose=True): """Read next received packet. @@ -218,32 +217,34 @@ class RxQueue(PacketVerifier): :type ignore: list :type verbose: bool - :return: Ether() initialized object from packet data. + :returns: Ether() initialized object from packet data. :rtype: scapy.Ether """ - (rlist, _, _) = select.select([self._sock], [], [], timeout) - if self._sock not in rlist: - return None - - pkt = self._sock.recv(0x7fff) - pkt_pad = auto_pad(pkt) - print 'Received packet on {0} of len {1}'.format(self._ifname, len(pkt)) - if verbose: - Ether(pkt).show2() - print - + ignore_list = list() if ignore is not None: - for i, ig_pkt in enumerate(ignore): - # Auto pad all packets in ignore list - ignore[i] = auto_pad(ig_pkt) for ig_pkt in ignore: - if ig_pkt == pkt_pad: - # Found the packet in ignore list, get another one - # TODO: subtract timeout - time_spent in here - ignore.remove(ig_pkt) - return self.recv(timeout, ignore, verbose) - - return Ether(pkt) + # Auto pad all packets in ignore list + ignore_list.append(str(auto_pad(ig_pkt))) + while True: + rlist, _, _ = select.select([self._sock], [], [], timeout) + if self._sock not in rlist: + return None + + pkt = self._sock.recv(0x7fff) + pkt_pad = str(auto_pad(pkt)) + print(f"Received packet on {self._ifname} of len {len(pkt)}") + if verbose: + if hasattr(pkt, u"show2"): + pkt.show2() + else: + # Never happens in practice, but Pylint does not know that. + print(f"Unexpected instance: {pkt!r}") + print() + if pkt_pad in ignore_list: + ignore_list.remove(pkt_pad) + print(u"Received packet ignored.") + continue + return pkt class TxQueue(PacketVerifier): @@ -256,52 +257,68 @@ class TxQueue(PacketVerifier): """ def __init__(self, interface_name): PacketVerifier.__init__(self, interface_name) + self._sock = conf.L2socket(iface=interface_name, type=ETH_P_ALL) def send(self, pkt, verbose=True): """Send packet out of the bound interface. :param pkt: Packet to send. - :param verbose: Used to supress detailed logging of sent packets. + :param verbose: Used to suppress detailed logging of sent packets. :type pkt: string or scapy Packet derivative. :type verbose: bool """ - print 'Sending packet out of {0} of len {1}'.format(self._ifname, - len(pkt)) + pkt = auto_pad(pkt) + print(f"Sending packet out of {self._ifname} of len {len(pkt)}") if verbose: - Ether(str(pkt)).show2() - print + pkt.show2() + print() - pkt = auto_pad(str(pkt)) self._sock.send(pkt) -class Interface(object): +class Interface: + """Class for network interfaces. Contains methods for sending and receiving + packets.""" def __init__(self, if_name): + """Initialize the interface class. + + :param if_name: Name of the interface. + :type if_name: str + """ self.if_name = if_name self.sent_packets = [] self.rxq = RxQueue(if_name) self.txq = TxQueue(if_name) def send_pkt(self, pkt): + """Send the provided packet out the interface.""" self.sent_packets.append(pkt) self.txq.send(pkt) def recv_pkt(self, timeout=3): + """Read one packet from the interface's receive queue. + + :param timeout: Timeout value in seconds. + :type timeout: int + :returns: Ether() initialized object from packet data. + :rtype: scapy.Ether + """ return self.rxq.recv(timeout, self.sent_packets) def create_gratuitous_arp_request(src_mac, src_ip): """Creates scapy representation of gratuitous ARP request.""" - return (Ether(src=src_mac, dst='ff:ff:ff:ff:ff:ff') / - ARP(psrc=src_ip, hwsrc=src_mac, pdst=src_ip)) + return (Ether(src=src_mac, dst=u"ff:ff:ff:ff:ff:ff") / + ARP(psrc=src_ip, hwsrc=src_mac, pdst=src_ip) + ) def auto_pad(packet): """Pads zeroes at the end of the packet if the total len < 60 bytes.""" - padded = str(packet) - if len(padded) < 60: - padded += ('\0' * (60 - len(padded))) - return padded + # padded = str(packet) + if len(packet) < 60: + packet[Raw].load += (b"\0" * (60 - len(packet))) + return packet def checksum_equal(chksum1, chksum2): @@ -317,7 +334,7 @@ def checksum_equal(chksum1, chksum2): :type chksum1: uint16 :type chksum2: uint16 - :return: True if checksums are equivalent, False otherwise. + :returns: True if checksums are equivalent, False otherwise. :rtype: boolean """ if chksum1 == 0xFFFF: