def foo(in_filename, out_filename): # open the input file for reading f = PcapReader(in_filename) # open the output file for writing o = PcapWriter(out_filename) # read the first packet from the input file p = f.read_packet() # while we haven't processed the last packet while p: layer = p.firstlayer() while not isinstance(layer, NoPayload): if (type(layer) is IPv6): new_layer = IP() del new_layer.ihl new_layer.ttl = layer.hlim new_layer.proto = layer.nh new_layer.src = ".".join(map(str, six2four(layer.src))) new_layer.dst = ".".join(map(str, six2four(layer.dst))) new_layer.add_payload(layer.payload) prev_layer = layer.underlayer del layer prev_layer.remove_payload() prev_layer.add_payload(new_layer) if type(prev_layer) is Ether: prev_layer.type = ETH_P_IP layer = new_layer if layer.default_fields.has_key('chksum'): del layer.chksum if layer.default_fields.has_key('len'): del layer.len # advance to the next layer layer = layer.payload # write the packet we just dissected into the output file o.write(p) # read the next packet p = f.read_packet() # close the input file f.close() # close the output file o.close()
# Construct UDP header udp = UDP(sport=7070, dport=9090, chksum=0) udp.len = 200 # This should be the combined length of all fragments # Construct payload payload = "A" * 72 # Put 80 bytes in the first fragment (72 byte from payload + 8byte udp header) # Construct the entire packet and send it out pkt = ip / udp / payload # For other fragments, we should use ip/payload send(pkt, verbose=0) pkt.show() #----------------------second fragment--------------------- print( "----------------------------------second fragment---------------------------------" ) ip.proto = 17 payload2 = "B" * 80 # 80 / 8 ip.frag = 10 pkt2 = ip / payload2 send(pkt2, verbose=0) pkt2.show() #----------------------third fragment--------------------- print( "----------------------------------Third fragment---------------------------------" ) payload3 = "C" * 40 ip.frag = 20 ip.flags = 0 pkt3 = ip / payload3 send(pkt3, verbose=0) pkt3.show()
if j != 0: packet_ihl = IP(dst=list_of_network_addresses[j]) / TCP(dport=22) packet_tos = IP(dst=list_of_network_addresses[j]) / TCP(dport=22) packet_len = IP(dst=list_of_network_addresses[j]) / TCP(dport=22) packet_id = IP(dst=list_of_network_addresses[j]) / TCP(dport=22) packet_frag = IP(dst=list_of_network_addresses[j]) / TCP(dport=22) packet_ttl = IP(dst=list_of_network_addresses[j]) / TCP(dport=22) packet_proto = IP(dst=list_of_network_addresses[j]) / TCP(dport=22) packet_ihl.ihl = 18 packet_tos.tos = 18 packet_len.len = 18 packet_id.id = 18 packet_frag.frag = 18 packet_ttl.ttl = 18 packet_proto.proto = 18 answer_ihl = sr(packet_ihl, timeout=4) answer_tos = sr(packet_tos, timeout=4) answer_len = sr(packet_len, timeout=4) answer_id = sr(packet_id, timeout=4) answer_frag = sr(packet_frag, timeout=4) answer_ttl = sr(packet_ttl, timeout=4) answer_proto = sr(packet_proto, timeout=4) if len(answer_ihl[0]) != 0: if len( nx.dijkstra_path(graph_ihl, list_of_network_addresses[0], list_of_network_addresses[j])) == 2: graph_ihl.add_edge(str(list_of_network_addresses[0]), str(list_of_network_addresses[j]),
def getIPPacket(self): """ 构造IP数据包 :return: """ # chksum = self.entries[9].get() try: eth = Ether() eth.src = self.entries[0].get() eth.dst = self.entries[1].get() eth.type = int(self.entries[2].get()) ip_packet = IP() ip_packet.versionion = int(self.entries[3].get()) ip_packet.ihl = int(self.entries[4].get()) ip_packet.tos = int(self.entries[5].get()) ip_packet.len = int(self.entries[6].get()) ip_packet.id = int(self.entries[7].get()) ip_packet.flags = int(self.entries[8].get()) ip_packet.frag = int(self.entries[9].get()) ip_packet.ttl = int(self.entries[10].get()) ip_packet.proto = int(self.entries[11].get()) payload = self.entries[16].get() ip_packet.src = self.entries[13].get() ip_packet.dst = self.entries[14].get() # 不含payload计算首部校验和 if payload == '': print("无payload的IP报文") ip_packet.show() checksum_scapy = IP(raw(ip_packet)).chksum # 自主计算验证IP首部检验和并进行填充 print("scapy自动计算的IP首部检验和是:%04x (%s)" % (checksum_scapy, str(checksum_scapy))) # 1.将IP首部和自动设置为0 ip_packet.chksum = 0 # 2.生成ip首部的数据字符串 x = raw(ip_packet) ipString = "".join("%02x" % orb(x) for x in x) # 3.将ip首部的数据字符串转换成字节数组 ipbytes = bytearray.fromhex(ipString) # 4.调用校验和计算函数计算校验和 checksum_self = self.IP_headchecksum(ipbytes) # 5.进行校验和验证 print("验证计算IP首部的检验和是:%04x (%s)" % (checksum_self, str(checksum_self))) # 含payload计算首部校验和 else: print("含有payload的IP报文") ip_packet = ip_packet / payload ip_packet.show() ip_packet.len = 20 + len(payload) checksum_scapy = IP(raw(ip_packet)).chksum print("scapy自动计算的IP首部检验和是:%04x (%s)" % (checksum_scapy, str(checksum_scapy))) ip_packet.chksum = 0 ip_packet.ihl = 5 print('\n 报文长度是:%s' % str(ip_packet.len)) x = raw(ip_packet) ipString = "".join("%02x" % orb(x) for x in x) ipbytes = bytearray.fromhex(ipString) checksum_self = self.IP_headchecksum(ipbytes[0:ip_packet.ihl * 4]) print("验证计算IP首部的检验和是:%04x (%s)" % (checksum_self, str(checksum_self))) if checksum_self == checksum_scapy: print("检验和正确") else: print("检验和不正确") ip_packet.chksum = checksum_self self.entries[12].delete(0, END) self.entries[12].insert(0, hex(ip_packet.chksum)) ip_packet.show() self.resultText.insert('end', ip_packet.summary() + '\n') self.resultText.insert('end', str(ip_packet) + '\n') return eth / ip_packet except Exception as e: print(e.with_traceback()) finally: pass