--- /dev/null
+#!/usr/bin/env python
+# Copyright (c) 2016 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:
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Traffic script that sends an DHCP OFFER message and checks if the DHCP
+REQUEST contains all required fields."""
+
+import sys
+
+from scapy.layers.l2 import Ether
+from scapy.layers.inet import IP, UDP, UDP_SERVICES
+from scapy.layers.dhcp import BOOTP, DHCP
+
+from resources.libraries.python.PacketVerifier import RxQueue, TxQueue
+from resources.libraries.python.TrafficScriptArg import TrafficScriptArg
+
+
+def is_discover(pkt):
+ """If DHCP message type option is set to dhcp discover return True,
+ else return False. False is returned also if exception occurs."""
+ dhcp_discover = 1
+ try:
+ dhcp_options = pkt['BOOTP']['DHCP options'].options
+ message_type = filter(lambda x: x[0] == 'message-type',
+ dhcp_options)
+ message_type = message_type[0][1]
+ return message_type == dhcp_discover
+ except:
+ return False
+
+
+def is_request(pkt):
+ """If DHCP message type option is DHCP REQUEST return True,
+ else return False. False is returned also if exception occurs."""
+ dhcp_request = 3
+ try:
+ dhcp_options = pkt['BOOTP']['DHCP options'].options
+ message_type = filter(lambda x: x[0] == 'message-type',
+ dhcp_options)
+ message_type = message_type[0][1]
+ return message_type == dhcp_request
+ except:
+ return False
+
+
+def main():
+ """Main function of the script file."""
+ args = TrafficScriptArg(['client_mac', 'server_mac', 'server_ip',
+ 'client_ip', 'client_mask'],
+ ['hostname', 'offer_xid'])
+
+ server_if = args.get_arg('rx_if')
+ server_mac = args.get_arg('server_mac')
+ server_ip = args.get_arg('server_ip')
+
+ client_mac = args.get_arg('client_mac')
+ client_ip = args.get_arg('client_ip')
+ client_mask = args.get_arg('client_mask')
+
+ hostname = args.get_arg('hostname')
+ offer_xid = args.get_arg('offer_xid')
+
+ rx_src_ip = '0.0.0.0'
+ rx_dst_ip = '255.255.255.255'
+
+ rxq = RxQueue(server_if)
+ txq = TxQueue(server_if)
+ sent_packets = []
+
+ for _ in range(10):
+ dhcp_discover = rxq.recv(10)
+ if is_discover(dhcp_discover):
+ break
+ else:
+ raise RuntimeError("DHCP DISCOVER Rx error.")
+
+ dhcp_offer = Ether(src=server_mac, dst=dhcp_discover.src)
+ dhcp_offer /= IP(src=server_ip, dst="255.255.255.255")
+ dhcp_offer /= UDP(sport=67, dport=68)
+ dhcp_offer /= BOOTP(op=2,
+ # if offer_xid differs from xid value in DHCP DISCOVER
+ # the DHCP OFFER has to be discarded
+ xid=int(offer_xid) if offer_xid
+ else dhcp_discover['BOOTP'].xid,
+ yiaddr=client_ip,
+ siaddr=server_ip,
+ chaddr=dhcp_discover['BOOTP'].chaddr)
+ dhcp_offer_options = [("message-type", "offer"), # Option 53
+ ("subnet_mask", client_mask), # Option 1
+ ("server_id", server_ip), # Option 54, dhcp server
+ ("lease_time", 43200), # Option 51
+ "end"]
+ dhcp_offer /= DHCP(options=dhcp_offer_options)
+
+ txq.send(dhcp_offer)
+ sent_packets.append(dhcp_offer)
+
+ max_other_pkts = 10
+ for _ in range(0, max_other_pkts):
+ dhcp_request = rxq.recv(5, sent_packets)
+ if not dhcp_request:
+ raise RuntimeError("DHCP REQUEST Rx timeout.")
+ if is_request(dhcp_request):
+ break
+ else:
+ raise RuntimeError("Max RX packet limit reached.")
+
+ if offer_xid:
+ # if offer_xid differs from xid value in DHCP DISCOVER the DHCP OFFER
+ # has to be discarded
+ raise RuntimeError("DHCP REQUEST received. DHCP OFFER with wrong XID "
+ "has not been discarded.")
+
+ # CHECK ETHER, IP, UDP
+ if dhcp_request.dst != dhcp_discover.dst:
+ raise RuntimeError("Destination MAC error.")
+ print "Destination MAC: OK."
+
+ if dhcp_request.src != dhcp_discover.src:
+ raise RuntimeError("Source MAC error.")
+ print "Source MAC: OK."
+
+ if dhcp_request['IP'].dst != rx_dst_ip:
+ raise RuntimeError("Destination IP error.")
+ print "Destination IP: OK."
+
+ if dhcp_request['IP'].src != rx_src_ip:
+ raise RuntimeError("Source IP error.")
+ print "Source IP: OK."
+
+ if dhcp_request['IP']['UDP'].dport != UDP_SERVICES.bootps:
+ raise RuntimeError("BOOTPs error.")
+ print "BOOTPs: OK."
+
+ if dhcp_request['IP']['UDP'].sport != UDP_SERVICES.bootpc:
+ raise RuntimeError("BOOTPc error.")
+ print "BOOTPc: OK."
+
+ # CHECK BOOTP
+ if dhcp_request['BOOTP'].op != dhcp_discover['BOOTP'].op:
+ raise RuntimeError("BOOTP operation error.")
+ print "BOOTP operation: OK"
+
+ if dhcp_request['BOOTP'].xid != dhcp_discover['BOOTP'].xid:
+ raise RuntimeError("BOOTP XID error.")
+ print "BOOTP XID: OK"
+
+ if dhcp_request['BOOTP'].ciaddr != '0.0.0.0':
+ raise RuntimeError("BOOTP ciaddr error.")
+ print "BOOTP ciaddr: OK"
+
+ ca = dhcp_request['BOOTP'].chaddr[:dhcp_request['BOOTP'].hlen].encode('hex')
+ if ca != client_mac.replace(':', ''):
+ raise RuntimeError("BOOTP client hardware address error.")
+ print "BOOTP client hardware address: OK"
+
+ if dhcp_request['BOOTP'].options != dhcp_discover['BOOTP'].options:
+ raise RuntimeError("DHCP options error.")
+ print "DHCP options: OK"
+
+ # CHECK DHCP OPTIONS
+ dhcp_options = dhcp_request['DHCP options'].options
+
+ hn = filter(lambda x: x[0] == 'hostname', dhcp_options)
+ if hostname:
+ try:
+ if hn[0][1] != hostname:
+ raise RuntimeError("Client's hostname doesn't match.")
+ except IndexError:
+ raise RuntimeError("Option list doesn't contain hostname option.")
+ else:
+ if len(hn) != 0:
+ raise RuntimeError("Option list contains hostname option.")
+ print "Option 12 hostname: OK"
+
+ # Option 50
+ ra = filter(lambda x: x[0] == 'requested_addr', dhcp_options)[0][1]
+ if ra != client_ip:
+ raise RuntimeError("Option 50 requested_addr error.")
+ print "Option 50 requested_addr: OK"
+
+ # Option 53
+ mt = filter(lambda x: x[0] == 'message-type', dhcp_options)[0][1]
+ if mt != 3: # request
+ raise RuntimeError("Option 53 message-type error.")
+ print "Option 53 message-type: OK"
+
+ # Option 54
+ sid = filter(lambda x: x[0] == 'server_id', dhcp_options)[0][1]
+ if sid != server_ip:
+ raise RuntimeError("Option 54 server_id error.")
+ print "Option 54 server_id: OK"
+
+ # Option 55
+ prl = filter(lambda x: x[0] == 'param_req_list', dhcp_options)[0][1]
+ if prl != '\x01\x1c\x02\x03\x0f\x06w\x0c,/\x1ay*':
+ raise RuntimeError("Option 55 param_req_list error.")
+ print "Option 55 param_req_list: OK"
+
+ # Option 255
+ if 'end' not in dhcp_options:
+ raise RuntimeError("end option error.")
+ print "end option: OK"
+
+ sys.exit(0)
+
+if __name__ == "__main__":
+ main()
Code Review / csit.git / blobdiff