北邮计算机网络课程设计DNS服务器

精选优质文档-----倾情为你奉上精选优质文档-----倾情为你奉上专心---专注---专业专心---专注---专业精选优质文档-----倾情为你奉上专心---专注---专业北邮计算机网络课程设计DNS服务器1环境操作系统随意,语言python2.72.文件Socket.py说明完成缓存检测,确定是回应,还是转发,如果是回应,确定是本地回应还是外部应答转发importsocketimportmydicimportcharhandleimportmakeframes=socket.socket(socket.AF_INET,socket.SOCK_DGRAMport=53the_dic=mydic.get_web_ip(client_request={}client_request_index={}reverse_map={}key_record=0client_wait=[]s.bind(('',porttime_rest=0request_general=''print'running'whileTrue:try:msg,(client,port=s.recvfrom(1024except:print'Timeout!'continuerequest=[]request=list(msgrequre_web=charhandle.get_request(request[12:]website=''.join(requre_webif(port==53:answer=[]answer=list(msgprint"Type:RemoteResponse"print"remoteansweris:"response_ip=msg[-4]+msg[-3]+msg[-2]+msg[-1]char_ip=socket.inet_ntoa(response_ipprintwebsite+'hastheip:'+char_ipfre=mydic.storeForUpdate(website,char_ipprint'withthefrequenceof'+str(fre###real_request=client_request[request[0]+request[1]]foreach_clientinclient_wait:my_key=client_request[request[0]+request[1]+str(each_client]ifclient_request_index.get(my_key!=None:s.sendto(msg,client_request_index[my_key]print"ResponsetoipandClientport:"printclient_request_index[my_key]breakelse:print"Type:ClientRequest"print"ipandport:"print(client,port###requre_web=charhandle.get_request(request[12:]###website=''.join(requre_webprint"Requestwebsite:"+websiteif(the_dic.get(website!=None:print"Foundinlocalcache:"re_ip=the_dic.get(websiteprintre_ipfre=mydic.storeForUpdate(websiteprintre_ip[0]+'withfrequence'+str(frezhen=makeframe.make(re_ip[0],msgs.sendto(zhen,(client,portelse:print"needtoaskremoteserver"key_record=key_record+1request_general=key_recordclient_request[request[0]+request[1]+str(client]=request_generalclient_request_index[request_general]=(client,portifclientnotinclient_wait:client_wait.append(client#selectauthorityDNSserverasyouwishs.sendto(msg,('',53time_rest=time_rest+1try:if(time_rest==50:print'payattention'print'######################'mydic.updateCache(print'######################'the_dic=mydic.get_web_ip(time_rest=0except:print'notvalidfrequence'print'--------------------'s.close(Mydic.py完成本地查询,LRU算法维护本地缓存,socket.py第97行的time_request值可以确定更新缓存的频率,可以直接输出在dnsrelay.txt内,但是为了方便观测变化,我输出到了dnsrelaycopy.txt里面,运行一段时间之后,可以去看看学习到的新条目importpickleimportosimportthreadingA=[]d_web_ip={}d_ip_web={}update_dic={}data=open('dnsrelay.txt'foreach_lineindata:try:(ip,sitecopy=each_line.split('',1(site,nothing=str(sitecopy.split('\n',1d_web_ip[site]=[ip,1]d_ip_web[ip]=siteexcept:print'fileerror'data.close(try:withopen('newdnsrelay.pickle','wb'asnewdnsrelay_file:pickle.dump(d_web_ip,newdnsrelay_fileexceptIOErroraserr:print'Fileerror:'+str(errexceptpickle.PickleErrorasperr:print'Picklingerror:'+str(perrdefget_web_ip(:withopen('newdnsrelay.pickle','rb'asf:globalupdate_dicupdate_dic=pickle.load(freturnupdate_dic.copy(return(NonedefstoreForUpdate(web_site,add=None:globalupdate_dicif(update_dic.get(web_site!=None:add_frequen=update_dic[web_site]add_frequen[1]=add_frequen[1]+1printweb_site+'frequenceincrase1,withip'+add_frequen[0]returnadd_frequen[1]else:update_dic[web_site]=[add,1]print'recordforanewsite'return1defupdateCache(:globalupdate_dicm=update_dic.copy(t=threading.Thread(target=my_thread,kwargs=mprint'readytoupdatelocalcache't.start(t.join(defmy_thread(*argu,**arg:frequence=[]remain_dic={}foreach_keyinarg:tmp=arg[each_key]if(tmp[1]notinfrequence:frequence.append(tmp[1]if(tmp[0]=='':remain_dic[each_key]=''print'variousfrequence:'foreachinfrequence:print'have'+str(eachforeach_keyinremain_dic:arg.pop(each_key#enimilatebani=0while(i<30:max_frequence=max(frequenceforeach_keyinarg:tmp=arg[each_key]if(tmp[1]==max_frequence:remain_dic[each_key]=tmp[0]i=i+1if(i==30:break;frequence.remove(max_frequenceif(notfrequence:###nomorebreak;updateFile(remain_dicdefupdateFile(new_dic:f=open('dnsrelaycopy.txt','w'foreach_keyinnew_dic:word=str(new_dic[each_key]+''+str(each_keyf.write(wordf.write('\n'new_dic[each_key]=[new_dic[each_key],0]try:withopen('newdnsrelay.pickle','wb'asnewdnsrelay_file:pickle.dump(new_dic,newdnsrelay_fileexceptIOErroraserr:print'Fileerror:'+str(errexceptpickle.PickleErrorasperr:print'Picklingerror:'+str(perrMakefram.py成帧模块，形成对外围权威服务器的询问帧importsocketdefmake(re_ip,msg:tmp_list=[]forchinmsg:tmp_list.append(chtmp_list[4:12]=['\x00','\x01','\x00','\x01','\x00','\x00','\x00','\x00']tmp_list=tmp_list+['\xc0','\x0c','\x00','\x01','\x00\','\x01','\x00','\x00','\x02','\x58','\x00','\x04']dive_ip=socket.inet_aton(re_ipch_ip=[]foreach_chindive_ip:ch_ip.append(each_chtmp_list=tmp_list+ch_i