【智能路由器】设备流量、网速统计及上下线提醒（基于netfilter编程）

【智能路由器】设备流量、网速统计及上下线提醒（基于netfilter编程）模块目的本文用户流量统计是统计路由器子网下每台设备的流量，下图展现了该模块具体是要实现怎样的功能内核模块依然是在netfilter的框架上进行数据捕获，分别监控每台子网设备流量信息。原理：在netfilter的pre_routing统计上传流量和上行速度以及在post_routing节点统计下载流量和下行速度，通过/proc文件系统提供给上层应用程序利用。流量拦截及统计关键代码如下/*目的:统计每个MAC的上传流量*/staticunsignedintflow_hook_out(unsignedinthooknum,structsk_buff*skb,conststructnet_device*in,conststructnet_device*out,int(*okfn)(structsk_buff*)){structethhdr*eth;structiphdr*ip;uint32_tip1,ip2;if(!skb)returnNF_ACCEPT;if(skb->protocol!=htons(0x0800))returnNF_ACCEPT;eth=eth_hdr(skb);if(!eth){printk("ethiserror!\n");returnNF_ACCEPT;}ip=ip_hdr(skb);if(!ip)returnNF_ACCEPT;if(!strnicmp(in->name,"br0",strlen("br0")))//流出流量,在pre_routing统计，统计源mac,ip{ip1=(ip->saddr)&0x00ffffff;ip2=(local_ip.IP)&0x00ffffff;if(ip1!=ip2)//subnet{returnNF_ACCEPT;}if(ip->saddr==local_ip.IP)//localreturnNF_ACCEPT;ip1=ip1&0xff000000;if(ntohl(ip1)==255)//broadcastreturnNF_ACCEPT;//mutex_lock(&visit_mutex_tx);add_maclist_data(Mac_flow_tableTX,eth->h_source,ip->saddr,ntohs(ip->tot_len));//mutex_unlock(&visit_mutex_tx);}returnNF_ACCEPT;}structnf_hook_opsflow_ops_out={//外出流量.list={NULL,NULL},.hook=flow_hook_out,.pf=PF_INET,.hooknum=NF_INET_PRE_ROUTING,//必须在NAT转发前统计.priority=NF_IP_PRI_FIRST+1//.hooknum=NF_INET_POST_ROUTING,//.priority=NF_IP_PRI_LAST-1};代码给出了上传流量的统计方法，下载流量统计代码如法炮制，不再贴出。代码思路步骤：1.代码首先剔除arp数据（提取ip包）2.过滤局域网外其他干扰设备数据、本地数据、广播数据3.添加到设备链表，这里做了一个单向链表用于存储设备mac、ip、流量、网速等信息。add_maclist_data()该函数用于向链表中添加数据设备网速计算及打印关键代码如下：intmac_func(void*data){uint32_tlen=0;uint32_tlenRx=0;while(!kthread_should_stop()){//ssleep(10);msleep(500);mutex_lock(&visit_mutex_tx);len=strlen(flow_buf)+40;if(len<1800)//上传流量{memset(flow_buf,0,len);//memset(flow_buf,0,sizeof(flow_buf));delete_macnode_by_ct(Mac_flow_tableTX);//clearofflinemacflow_format_and_clear(Mac_flow_tableTX,flow_buf);}else{free_maclist(Mac_flow_tableTX);//clearallmac,theremaybealotofinvalidmac!Mac_flow_tableTX=create_maclist();//anewlist}mutex_unlock(&visit_mutex_tx);msleep(500);mutex_lock(&visit_mutex_rx);lenRx=strlen(flow_bufRx)+40;if(lenRx<1800)//下发流量,只有ip{memset(flow_bufRx,0,lenRx);//memset(flow_bufRx,0,sizeof(flow_bufRx));delete_ipnode_by_ct(ip_flow_tableRx);ipflow_format_and_clear(ip_flow_tableRx,flow_bufRx);}else{free_iplist(ip_flow_tableRx);ip_flow_tableRx=create_iplist();}mutex_unlock(&visit_mutex_rx);}return1;}intk_threadinit(void){info_kthread=kthread_run(mac_func,NULL,"flow");if(NULL==info_kthread)return-1;return1;}intk_threadstop(void){kthread_stop(info_kthread);info_kthread=NULL;return1;}在内核创建了一个线程用于统计网速，维护设备链表。代码每秒统计一次设备网速，同时剔除一些已经下线的设备，防止输出缓冲区过满（删除整个链表然后重新建表）。将数据映射到/proc虚拟文件系统关键代码如下：staticintflow_read(char*page,char**start,off_toff,intcount,int*eof,void*data){intlen;mutex_lock(&visit_mutex_tx);len=strlen(flow_buf);if(off>len){mutex_unlock(&visit_mutex_tx);*eof=1;return0;}if(count>len-off){count=len-off;*eof=1;}memcpy(page,flow_buf,count);mutex_unlock(&visit_mutex_tx);*start=page+off;//*eof=1;//returnoff+count;returncount;}staticintflow_readRx(char*page,char**start,off_toff,intcount,int*eof,void*data){intlen;//printk("flow_readRx\n");mutex_lock(&visit_mutex_rx);len=strlen(flow_bufRx);if(off>len){mutex_unlock(&visit_mutex_rx);*eof=1;return0;}if(count>len-off){count=len-off;*eof=1;}memcpy(page,flow_bufRx,count);mutex_unlock(&visit_mutex_rx);*start=page+off;//*eof=1;//returnoff+count;returncount;}intinit_flowproc_moudle(void){intret=0;flow_root=proc_mkdir("flow_m",NULL);if(flow_root==NULL){printk("createdirflow_rootfail\n");return-1;}//Txproc_entry=create_proc_entry("flowwatchTx",0444,flow_root);if(proc_entry==NULL){printk("fortune:couldn'tcreateprocentry\n");ret=-2;returnret;}proc_entry->read_proc=flow_read;//Rxproc_entryRx=create_proc_entry("flowwatchRx",0444,flow_root);if(proc_entryRx==NULL){printk("fortune:couldn'tcreateprocentry\n");ret=-3;returnret;}proc_entryRx->read_proc=flow_readRx;returnret;}voidexit_flowproc_moudle(void){remove_proc_entry("flowwatchTx",flow_root);//删除文件remove_proc_entry("flowwatchRx",flow_root);remove_proc_entry("flow_m",NULL);//删除目录}代码在/proc下建立/flow_m文件夹，同时在/proc/flow_m下建立flowwatchTx和flowwatchRx文件，对这两个文件分别进行读取可以得到设备流量信息。应用层模块应用层模块对设备上传及下载流量进行了整合，同时具备设备上下线提醒功能。主要代码如下：typedefstd::list<Flow_Info>F_list;F_listFlow_table;/*name:cat_user_flowdescription:cat/proc/flow_m/flowwatchTxcat/proc/flow_m/flowwatchRx*/intcat_user_flow(HASH_TABLE*pMACtable){Flow_Infotemflow;charup_buf[80];chardown_buf[80];FILE*up_flow;FILE*down_flow;charflag=0;time_tcurrenttime;up_flow=fopen("flowwatchTx","r");down_flow=fopen("flowwatchRx","r");if(up_flow==NULL){std::cout<<"openfilefail!"<<std::endl;return-1;}if(down_flow==NULL){std::cout<<"openfilefail!"<<std::endl;return-1;}//readfirstlineanddropoutif(NULL==fgets(up_buf,sizeof(up_buf),up_flow)){//errororendoffilestd::cout<<"readfilefailed!"<<std::endl;fclose(up_flow);fclose(down_flow);return-2;}if(NULL==fgets(down_buf,sizeof(down_buf),down_flow)){//errororendoffilestd::cout<<"readfilefailed!"<<std::endl;fclose(up_flow);fclose(down_flow);return-2;}currenttime=time((time_t*)NULL);std::cout<<"currenttime:"<<currenttime<<std::endl;for(;;)//Tx{memset(up_buf,0,sizeof(up_buf));if(NULL==fgets(up_buf,sizeof(up_buf),up_flow))//errororendoffilebreak;memset(&temflow,0,sizeof(temflow));sscanf(up_buf,"%s%s%s%s",temflow.mac,temflow.ip,temflow.upload,temflow.totalup);if(strncmp(temflow.ip,"",strlen(""))==0)continue;//updatelistfor(F_list::iteratorf_list_iter=Flow_table.begin();f_list_iter!=Flow_table.end();f_list_iter++){if(0==strncmp((*f_list_iter).mac,temflow.mac,strlen(temflow.mac))){memcpy((*f_list_iter).ip,temflow.ip,strlen(temflow.ip)+1);//addadditionalanullcharactermemcpy((*f_list_iter).upload,temflow.upload,strlen(temflow.upload)+1);memcpy((*f_list_iter).totalup,temflow.totalup,strlen(temflow.totalup)+1);(*f_list_iter).loop=0;(*f_list_iter).alive=currenttime-(*f_list_iter).s_time;flag=1;break;}}if(!flag)//newonlinedevice{charbuf[12];NODE*MACdataNode=NULL;ElemTypeval=0;memset(buf,0,sizeof(buf));memcpy(buf,temflow.mac,8);//getlocaltimetemflow.s_time=time((time_t*)NULL);temflow.NewOnlineD=1;//onlineaction//std::cout<<"*-*-*-*-*-*-*-*"<<std::endl;val=(ElemType)(MAC_str_to10)(buf);MACdataNode=find_data_in_hash(pMACtable,val);if(MACdataNode==NULL){std::cout<<"findnodata!\n"<<std::endl;//unfound!memcpy(temflow.dev_name,"unknown",strlen("unknown"));memcpy(temflow.dev_type,"unknown",strlen("unknown"));}else//findsuccess{memcpy(temflow.dev_name,((Code_to_Str_t*)MACdataNode->data)->remark,strlen(((Code_to_Str_t*)MACdataNode->data)->remark)+1);memcpy(low.dev_type,((Code_to_Str_t*)MACdataNode->data)->type,strlen(((Code_to_Str_t*)MACdataNode->data)->type)+1);}Flow_table.push_back(temflow);}flag=0;}if(Flow_table.empty()){std::cout<<"Flow_tableisempty"<<std::endl;fclose(up_flow);fclose(down_flow);charbuf[4];memset(buf,0,sizeof(buf));write_info(buf,dev_info_file,"w+");return-3;}while(1)//combineTxwithRx{memset(down_buf,0,sizeof(down_buf));if(NULL==fgets(down_buf,sizeof(down_buf),down_flow))//errororendoffilebreak;memset(&temflow,0,sizeof(temflow));sscanf(down_buf,"%s%s%s",temflow.ip,temflow.download,temflow.totaldown);for(F_list::iteratorf_list_iter=Flow_table.begin();f_list_iter!=Flow_table.end();f_list_iter++)//compareip{if(0==strncmp((*f_list_iter).ip,temflow.ip,strlen(temflow.ip))){memcpy((*f_list_iter).download,temflow.download,strlen(temflow.download)+1);memcpy((*f_list_iter).totaldown,temflow.totaldown,strlen(temflow.totaldown)+1);(*f_list_iter).looprx=0;break;//thisipinsertok!}//ifnotfind,ignoreit!}}for(F_list::iteratorf_list_iter=Flow_table.begin();f_list_iter!=Flow_table.end();f_list_iter++){(*f_list_iter).loop=(*f_list_iter).loop+1;(*f_list_iter).looprx=(*f_list_iter).looprx+1;}fclose(up_flow);fclose(down_flow);/*for(F_list::iteratorf_list_iter=Flow_table.begin();f_list_iter!=Flow_table.end();f_list_iter++){std::cout<<"****************"<<std::endl;std::cout<<(*f_list_iter).mac<<""<<(*f_list_iter).ip<<""<<(*f_list_iter).totalup<<std::endl;}*/return0;}/*name:description:noticeothersomeinformation*/intwrite_dev_info(pid_tpid){charbuf[256];memset(buf,0,sizeof(buf));write_info(buf,dev_info_file,"w+");//cleardev_info_filefor(F_list::iteratorf_list_iter=Flow_table.begin();f_list_iter!=Flow_table.end();f_list_iter++){memset(buf,0,sizeof(buf));sprintf(buf,"%d,%s,%s,%s,%s,%s,%s,%s,%s,%ld,%d\n",Flow_table.size(),(*f_list_iter).mac,(*f_list_iter).ip,(*f_list_iter).upload,(*f_list_iter).download,(*f_list_iter).totalup,(*f_list_iter).totaldown,(*f_list_iter).dev_name,(*f_list_iter).dev_type,(*f_list_iter).alive,(*f_list_iter).loop);printf("\n%s\n",buf);write_info(buf,dev_info_file,"a+");if(((*f_list_iter).loop>5)&&((*f_list_iter).looprx>5))//offlinecheckandnotice{memset(buf,0,sizeof(buf));sprintf(buf,"%s,%s,%s\n",(*f_list_iter).mac,(*f_list_iter).dev_type,(*f_list_iter).dev_name);printf("*******\nofflinenotice:%s,%s,%s\n",(*f_list_iter).mac,(*f_list_iter).dev_type,(*f_list_iter).dev_na