Python实现两端通信，模拟网络监控(单任务版本)

# encoding:utf-8 import time import struct import socket import select import sys def chesksum(data): n=len(data) m=n % 2 sum=0 for i in range(0, n - m ,2): sum += (data[i]) + ((data[i+1]) << 8)#传入data以每两个字节（十六进制）通过ord转十进制，第一字节在低位，第二个字节在高位 if m: sum += (data[-1]) #将高于16位与低16位相加 sum = (sum >> 16) + (sum & 0xffff) sum += (sum >> 16) #如果还有高于16位，将继续与低16位相加 answer = ~sum & 0xffff # 主机字节序转网络字节序列（参考小端序转大端序） answer = answer >> 8 | (answer << 8 & 0xff00) return answer def request_ping(data_type,data_code,data_checksum,data_ID,data_Sequence,payload_body): # 把字节打包成二进制数据 imcp_packet = struct.pack('>BBHHH32s',data_type,data_code,data_checksum,data_ID,data_Sequence,payload_body) icmp_chesksum = chesksum(imcp_packet) #获取校验和 # 把校验和传入，再次打包 imcp_packet = struct.pack('>BBHHH32s',data_type,data_code,icmp_chesksum,data_ID,data_Sequence,payload_body) return imcp_packet def raw_socket(dst_addr,imcp_packet): ''' 连接套接字,并将数据发送到套接字 ''' #实例化一个socket对象，ipv4，原套接字，分配协议端口 rawsocket = socket.socket(socket.AF_INET,socket.SOCK_RAW,socket.getprotobyname("icmp")) #记录当前请求时间 send_request_ping_time = time.time() #发送数据到网络 rawsocket.sendto(imcp_packet,(dst_addr,80)) #返回数据 return send_request_ping_time,rawsocket,dst_addr def reply_ping(send_request_ping_time,rawsocket,data_Sequence,timeout = 2): while True: #开始时间 started_select = time.time() #实例化select对象，可读rawsocket，可写为空，可执行为空，超时时间 what_ready = select.select([rawsocket], [], [], timeout) #等待时间 wait_for_time = (time.time() - started_select) #没有返回可读的内容，判断超时 if what_ready[0] == []: # Timeout return -1 #记录接收时间 time_received = time.time() #设置接收的包的字节为1024 received_packet, addr = rawsocket.recvfrom(1024) #获取接收包的icmp头 #print(icmpHeader) icmpHeader = received_packet[20:28] #反转编码 type, code, checksum, packet_id, sequence = struct.unpack( ">BBHHH", icmpHeader ) if type == 0 and sequence == data_Sequence: return time_received - send_request_ping_time #数据包的超时时间判断 timeout = timeout - wait_for_time if timeout <= 0: return -1 def dealtime(dst_addr,sumtime,shorttime,longtime,accept,i,time): sumtime+=time print(sumtime) if i==4: print("{0}的Ping统计信息：".format(dst_addr)) print("数据包：已发送={0},接收={1}，丢失={2}（{3}%丢失），\n往返行程的估计时间（以毫秒为单位）：\n\t最短={4}ms，最长={5}ms，平均={6}ms".format(i+1,accept,i+1-accept,(i+1-accept)/(i+1)*100,shorttime,longtime,sumtime)) def ping(host,count): send, accept, lost = 0, 0, 0 sumtime, shorttime, longtime, avgtime = 0, 1000, 0, 0 #TODO icmp数据包的构建 data_type = 8 # ICMP Echo Request data_code = 0 # must be zero data_checksum = 0 # "...with value 0 substituted for this field..." data_ID = 0 #Identifier data_Sequence = 1 #Sequence number payload_body = b'abcdefghijklmnopqrstuvwabcdefghi' #data # 将主机名转ipv4地址格式，返回以ipv4地址格式的字符串，如果主机名称是ipv4地址，则它将保持不变 dst_addr = socket.gethostbyname(host) # print("正在 Ping {0} [{1}] 具有 32 字节的数据:".format(host,dst_addr)) for i in range(0,int(count)): send=i+1 #请求ping数据包的二进制转换 icmp_packet = request_ping(data_type,data_code,data_checksum,data_ID,data_Sequence + i,payload_body) #连接套接字,并将数据发送到套接字 send_request_ping_time,rawsocket,addr = raw_socket(dst_addr,icmp_packet) #数据包传输时间 times = reply_ping(send_request_ping_time,rawsocket,data_Sequence + i) if times > 0: #print("来自 {0} 的回复: 字节=32 时间={1}ms".format(addr,int(times*1000))) accept+=1 return_time=int(times * 1000) sumtime += return_time if return_time > longtime: longtime = return_time if return_time < shorttime: shorttime = return_time time.sleep(0.2) else: lost+=1 # print("请求超时。") #if send == int(count): # print("{0}的Ping统计信息:".format(dst_addr)) # print("\t数据包：已发送={0},接收={1}，丢失={2}（{3}%丢失），\n往返行程的估计时间（以毫秒为单位）：\n\t最短={4}ms，最长={5}ms，平均={6}ms".format( # i + 1, accept, i + 1 - accept, (i + 1 - accept) / (i + 1) * 100, shorttime, longtime, sumtime/send)) return (i + 1 - accept) / (i + 1) * 100,sumtime/send if __name__ == "__main__": # if len(sys.argv) < 2: # sys.exit('Usage: ping.py <host>') # ping(sys.argv[1]) while True: #i=input("请输入要ping的主机或域名\n") j=input("请输入分组数量\n") ping('www.baidu.com',j) print("\n") # host='www.baidu.com' # ping(host)