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safe anti replay

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wangyu 2017-07-19 16:11:12 +08:00 committed by wangyu
parent 9bb8b25c73
commit 79effde630
1 changed files with 206 additions and 169 deletions
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375
main.cpp
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@ -48,16 +48,20 @@ char local_address[100], remote_address[100],source_address[100];
int local_port = -1, remote_port = -1;
int epollfd ;
uint32_t session_id=0;
uint32_t oppsite_session_id=0;
uint32_t my_id=0;
uint32_t oppsite_id=0;
uint32_t conv_id=0;
const int handshake_timeout=2000;
const int handshake_timeout=1000;
const int heartbeat_timeout=10000;
const int udp_timeout=2000;
const int heartbeat_interval=1000;
const int timer_interval=50;
const int timer_interval=500;
const int RETRY_TIME=3;
//const uint16_t tcp_window=50000;
@ -67,11 +71,13 @@ const int buf_len = 65535+100;
const int server_mode=2;
const int client_mode=1;
int prog_mode=0; //0 unset; 1client 2server
const int RETRY_TIME=3;
const int debug_mode=0;
int bind_fd;
int first_data_packet=0;
const int seq_mode=2; //0 dont increase /1 increase //increase randomly,about every 10 packet
const uint64_t epoll_timer_fd_sn=1;
@ -93,6 +99,18 @@ int udp_fd=-1;
int raw_recv_fd;
int raw_send_fd;
const int client_nothing=0;
const int client_syn_sent=1;
const int client_ack_sent=2;
const int client_heartbeat_sent=3;
const int client_ready=4;
int client_current_state=client_nothing;
int retry_counter;
long long last_state_time=0;
long long last_hb_sent_time=0;
char buf[buf_len];
char buf2[buf_len];
@ -122,17 +140,6 @@ struct sock_filter code[] = {
sock_fprog bpf;
const int client_nothing=0;
const int client_syn_sent=1;
const int client_ack_sent=2;
const int client_ready=3;
int client_current_state=client_nothing;
int retry_counter;
long long last_state_time=0;
long long last_hb_sent_time=0;
uint16_t ip_id=1;
//const int MTU=1440;
@ -699,18 +706,21 @@ int send_raw(packet_info_t &info,char * payload,int payloadlen)
int send_data(packet_info_t &info,char* data,int len,uint32_t id1,uint32_t id2 )
int send_data(packet_info_t &info,char* data,int len,uint32_t id1,uint32_t id2,uint32_t conv_id)
{
int new_len=1+sizeof(session_id)*2+len;
int new_len=1+sizeof(my_id)*3+len;
send_data_buf[0]='d';
uint32_t tmp;
tmp=htonl(id1);
memcpy(send_data_buf+1,&tmp,sizeof(session_id));
memcpy(send_data_buf+1,&tmp,sizeof(my_id));
tmp=htonl(id2);
memcpy(send_data_buf+1+sizeof(session_id),&tmp,sizeof(session_id));
memcpy(send_data_buf+1+sizeof(my_id),&tmp,sizeof(my_id));
memcpy(send_data_buf+1+sizeof(session_id)*2,data,len);
tmp=htonl(conv_id);
memcpy(send_data_buf+1+sizeof(my_id)*2,&tmp,sizeof(my_id));
memcpy(send_data_buf+1+sizeof(my_id)*3,data,len);
if(pre_send(send_data_buf,new_len)<0)
{
@ -722,15 +732,15 @@ int send_data(packet_info_t &info,char* data,int len,uint32_t id1,uint32_t id2 )
int send_hb(packet_info_t &info,uint32_t id1,uint32_t id2 )
{
int new_len=1+sizeof(session_id)*2;
int new_len=1+sizeof(my_id)*2;
send_data_buf[0]='h';
uint32_t tmp;
tmp=htonl(id1);
memcpy(send_data_buf+1,&tmp,sizeof(session_id));
memcpy(send_data_buf+1,&tmp,sizeof(my_id));
tmp=htonl(id2);
memcpy(send_data_buf+1+sizeof(session_id),&tmp,sizeof(session_id));
memcpy(send_data_buf+1+sizeof(my_id),&tmp,sizeof(my_id));
if(pre_send(send_data_buf,new_len)<0)
{
@ -742,7 +752,7 @@ int send_hb(packet_info_t &info,uint32_t id1,uint32_t id2 )
return 0;
}
int send_sync()
/*int send_sync()
{
//g_packet_info.seq=3;
g_packet_info.ack=0;
@ -751,7 +761,7 @@ int send_sync()
g_packet_info.psh=0;
send_raw(g_packet_info,0,0);
return 0;
}
}*/
uint32_t get_true_random_number()
{
@ -818,7 +828,6 @@ int fake_tcp_keep_connection_client() //for client
printf("state changed from nothing to syn_sent\n");
retry_counter=5;
g_packet_info.src_port=client_bind_to_a_new_port();
printf("using port %d\n",g_packet_info.src_port);
@ -828,9 +837,12 @@ int fake_tcp_keep_connection_client() //for client
g_packet_info.seq=get_true_random_number();
g_packet_info.ack_seq=0;//get_true_random_number();
g_packet_info.ts_ack=0;
send_sync(/*sync*/);//send sync
g_packet_info.ack=0;
g_packet_info.syn=1;
g_packet_info.psh=0;
send_raw(g_packet_info,0,0);
}
if(client_current_state==client_syn_sent &&get_current_time()-last_state_time>handshake_timeout)
{
@ -844,14 +856,12 @@ int fake_tcp_keep_connection_client() //for client
{
retry_counter--;
printf("retry send sync\n");
send_sync(/*sync*/);//send sync again
send_raw(g_packet_info,0,0);
last_state_time=get_current_time();
}
}
if(client_current_state==client_ack_sent &&get_current_time()-last_state_time>handshake_timeout)
{
printf("!!!!!\n");
fflush(stdout);
if(retry_counter==0)
{
client_current_state=client_nothing;
@ -864,16 +874,37 @@ int fake_tcp_keep_connection_client() //for client
send_raw(g_packet_info,0,0);
last_state_time=get_current_time();
printf("retry send ack counter left:%d\n",retry_counter);
fflush(stdout);
}
}
if(client_current_state==client_heartbeat_sent&&get_current_time()-last_state_time>handshake_timeout)
{
if(retry_counter==0)
{
client_current_state=client_nothing;
printf("state back to nothing\n");
goto begin;
}
else
{
retry_counter--;
send_hb(g_packet_info,my_id,oppsite_id);
last_state_time=get_current_time();
printf("retry send heart_beat counter left:%d\n",retry_counter);
printf("heartbeat sent <%x,%x>\n",oppsite_id,my_id);
}
}
if(client_current_state==client_ready)
{
if(debug_mode)printf("time %lld %lld\n",get_current_time(),last_state_time);
if(get_current_time()-last_hb_recv_time>heartbeat_timeout)
{
client_current_state=client_nothing;
my_id=get_true_random_number();
printf("state back to nothing\n");
return 0;
}
@ -883,24 +914,10 @@ int fake_tcp_keep_connection_client() //for client
return 0;
}
g_packet_info.syn=0;
g_packet_info.ack=1;
if(debug_mode)printf("heartbeat sent <%x,%x>\n",oppsite_id,my_id);
if(debug_mode)printf("heartbeat sent <%x,%x>\n",oppsite_session_id,session_id);
/*
buf[0]='h';
uint32_t tmp;
tmp=htonl(oppsite_session_id);
memcpy(buf+1+sizeof(session_id),&tmp,sizeof(session_id));
tmp=htonl(session_id);
memcpy(buf+1,&tmp,sizeof(session_id));
send_raw(g_packet_info,buf,sizeof(session_id)*2+1);*/
send_hb(g_packet_info,session_id,oppsite_session_id);
send_hb(g_packet_info,my_id,oppsite_id);
last_hb_sent_time=get_current_time();
//last_time=get_current_time();
}
}
@ -908,7 +925,7 @@ int fake_tcp_keep_connection_client() //for client
int fake_tcp_keep_connection_server()
{
//begin:
if(debug_mode) printf("timerxxxx!\n");
if(debug_mode) printf("timer!\n");
if(server_current_state==server_nothing)
{
return 0;
@ -919,7 +936,6 @@ int fake_tcp_keep_connection_server()
{
server_current_state=server_nothing;
printf("state back to nothing\n");
//send_raw(g_packet_info,0,0);
}
else
{
@ -928,22 +944,33 @@ int fake_tcp_keep_connection_server()
last_state_time=get_current_time();
printf("resend syn ack\n");
}
//send_raw(/*syn ack*/);
}
if(server_current_state==server_heartbeat_sent||server_current_state==server_ready)
if(server_current_state==server_heartbeat_sent &&get_current_time()-last_state_time>handshake_timeout)
{
if( (server_current_state==server_heartbeat_sent&&get_current_time()-last_hb_recv_time>handshake_timeout )
|| ( server_current_state==server_ready&&get_current_time()-last_hb_recv_time>heartbeat_timeout )
)
if(retry_counter==0)
{
server_current_state=server_nothing;
printf("state back to nothing\n");
}
else
{
retry_counter--;
send_hb(g_packet_info,my_id,0);
last_state_time=get_current_time();
printf("half heart beat sent<%x>\n",my_id);
}
}
if(server_current_state==server_ready)
{
if( get_current_time()-last_hb_recv_time>heartbeat_timeout )
{
printf("%lld %lld",get_current_time(),last_state_time);
server_current_state=server_nothing;
if(server_current_state==server_ready)
{
printf("changed session id\n");
session_id=get_true_random_number();
}
printf("changed session id\n");
my_id=get_true_random_number();
printf("state back to nothing\n");
printf("changed state to server_nothing111\n");
return 0;
@ -954,30 +981,10 @@ int fake_tcp_keep_connection_server()
return 0;
}
g_packet_info.syn=0;
g_packet_info.ack=1;
//g_packet_info.psh=1;
/*
buf[0]='h';
uint32_t tmp;
tmp=htonl(session_id);
memcpy(buf+1,&tmp,sizeof(session_id));
memset(buf+1+sizeof(session_id),0,sizeof(session_id));
send_raw(g_packet_info,buf,sizeof(session_id)*2+1);
*/
send_hb(g_packet_info,session_id,0);
send_hb(g_packet_info,my_id,oppsite_id);
last_hb_sent_time=get_current_time();
//last_time=get_current_time();
if(debug_mode) printf("heart beat sent<%x>\n",session_id);
fflush(stdout);
if(debug_mode) printf("heart beat sent<%x>\n",my_id);
}
}
@ -1033,9 +1040,10 @@ int client_raw_recv(iphdr * iph,tcphdr *tcph,char * data,int data_len)
send_raw(g_packet_info,0,0);
client_current_state=client_ack_sent;
printf("changed state to client_ack_sent\n");
last_state_time=get_current_time();
retry_counter=RETRY_TIME;
printf("changed state to client_ack_sent\n");
}
if(client_current_state==client_ack_sent )
{
@ -1044,8 +1052,9 @@ int client_raw_recv(iphdr * iph,tcphdr *tcph,char * data,int data_len)
printf("unexpected syn ack or other zero lenght packet\n");
return 0;
}
if(data_len!=sizeof(session_id)*2+1||data[0]!='h')
if(data_len!=sizeof(my_id)*2+1||data[0]!='h')
{
printf("not a heartbeat\n");
return 0;
}
if(iph->saddr!=g_packet_info.dst_ip||ntohs(tcph->source)!=g_packet_info.dst_port)
@ -1054,30 +1063,54 @@ int client_raw_recv(iphdr * iph,tcphdr *tcph,char * data,int data_len)
return 0;
}
oppsite_session_id= ntohl(* ((uint32_t *)&data[1]));
oppsite_id= ntohl(* ((uint32_t *)&data[1]));
printf("====first hb received %x\n==",oppsite_session_id);
printf("====first hb received %x\n==",oppsite_id);
printf("changed state to client_heartbeat_sent\n");
send_hb(g_packet_info,my_id,oppsite_id);
client_current_state=client_ready;
printf("changed state to client_ready\n");
send_hb(g_packet_info,session_id,oppsite_session_id);
/*
buf[0]='h';
uint32_t tmp;
tmp=htonl(session_id);
memcpy(buf+1,&tmp,sizeof(session_id));
tmp=htonl(oppsite_session_id);
memcpy(buf+1+sizeof(session_id),&tmp,sizeof(session_id));
send_raw(g_packet_info,buf,sizeof(session_id)*2+1);*/
//send_raw(g_packet_info,"hb",strlen("hb"));
client_current_state=client_heartbeat_sent;
last_state_time=get_current_time();
retry_counter=RETRY_TIME;
}
if(client_current_state==client_heartbeat_sent)
{
if( tcph->syn==1||tcph->ack!=1 ||data_len==0)
{
printf("unexpected syn ack or other zero lenght packet\n");
return 0;
}
if(data_len!=sizeof(my_id)*2+1||data[0]!='h')
{
printf("not a heartbeat\n");
return 0;
}
if(iph->saddr!=g_packet_info.dst_ip||ntohs(tcph->source)!=g_packet_info.dst_port)
{
printf("unexpected adress\n");
return 0;
}
uint32_t tmp_my_id= ntohl(* ((uint32_t *)&data[1+sizeof(my_id)]));
if(tmp_my_id!=my_id)
{
printf("auth fail\n");
return 0;
}
uint32_t tmp_oppsite_session_id=ntohl(* ((uint32_t *)&data[1]));
if(tmp_oppsite_session_id!=oppsite_id)
{
printf("oppsite id mismatch%x %x,ignore\n",tmp_oppsite_session_id,my_id);
return 0;
}
printf("changed state to client_ready\n");
client_current_state=client_ready;
last_state_time=get_current_time();
last_hb_recv_time=get_current_time();
}
if(client_current_state==client_ready )
{
if( tcph->syn==1||tcph->ack!=1 ||data_len==0)
@ -1091,32 +1124,39 @@ int client_raw_recv(iphdr * iph,tcphdr *tcph,char * data,int data_len)
return 0;
}
if(data_len==sizeof(session_id)*2+1&&data[0]=='h')
if(data_len==sizeof(my_id)*2+1&&data[0]=='h')
{
if(debug_mode)printf("heart beat received\n");
last_hb_recv_time=get_current_time();
return 0;
}
else if(data_len>=sizeof(session_id)*2+1&&data[0]=='d')
else if(data_len>=sizeof(my_id)*3+1&&data[0]=='d')
{
printf("received a data from fake tcp,len:%d\n",data_len);
uint32_t tmp_session_id= ntohl(* ((uint32_t *)&data[1+sizeof(session_id)]));
uint32_t tmp_session_id= ntohl(* ((uint32_t *)&data[1+sizeof(my_id)]));
if(tmp_session_id!=session_id)
if(tmp_session_id!=my_id)
{
printf("client session id mismatch%x %x,ignore\n",tmp_session_id,session_id);
printf("client session id mismatch%x %x,ignore\n",tmp_session_id,my_id);
return 0;
}
uint32_t tmp_oppsite_session_id=ntohl(* ((uint32_t *)&data[1]));
if(tmp_oppsite_session_id!=oppsite_session_id)
if(tmp_oppsite_session_id!=oppsite_id)
{
printf("server session id mismatch%x %x,ignore\n",tmp_oppsite_session_id,session_id);
printf("server session id mismatch%x %x,ignore\n",tmp_oppsite_session_id,my_id);
return 0;
}
uint32_t tmp_conv_id= ntohl(* ((uint32_t *)&data[1+sizeof(my_id)*2]));
if(tmp_conv_id!=conv_id)
{
printf("conv id mismatch%x %x,ignore\n",tmp_oppsite_session_id,my_id);
return 0;
}
last_hb_recv_time=get_current_time();
int ret=sendto(udp_fd,data+1+sizeof(session_id)*2,data_len -(1+sizeof(session_id)*2),0,(struct sockaddr *)&udp_old_addr_in,sizeof(udp_old_addr_in));
int ret=sendto(udp_fd,data+1+sizeof(my_id)*3,data_len -(1+sizeof(my_id)*3),0,(struct sockaddr *)&udp_old_addr_in,sizeof(udp_old_addr_in));
if(ret<0)perror("ret<0");
printf("%d byte sent\n",ret);
}
@ -1139,15 +1179,14 @@ int server_raw_recv(iphdr * iph,tcphdr *tcph,char * data,int data_len)
g_packet_info.syn=1;
g_packet_info.ack=1;
g_packet_info.seq=get_true_random_number();//not necessary to set
printf("sent syn ack\n");
fflush(stdout);
send_raw(g_packet_info,0,0);
server_current_state=server_syn_ack_sent;
printf("changed state to server_syn_ack_sent\n");
server_current_state=server_syn_ack_sent;
retry_counter=RETRY_TIME;
last_state_time=get_current_time();
}
@ -1160,17 +1199,19 @@ int server_raw_recv(iphdr * iph,tcphdr *tcph,char * data,int data_len)
return 0;
}
server_current_state=server_heartbeat_sent;
g_packet_info.syn=0;
g_packet_info.ack=1;
g_packet_info.seq+=1;////////is this right?
//send_raw(g_packet_info,"hb",strlen("hb"));
send_hb(g_packet_info,my_id,0); // send a hb immidately
printf("changed state to server_heartbeat_sent\n");
last_hb_recv_time=get_current_time(); //this ack is counted as hearbeat
server_current_state=server_heartbeat_sent;
last_state_time=get_current_time();
retry_counter=RETRY_TIME;
}
else if(server_current_state==server_heartbeat_sent)//heart beat received
{
@ -1180,47 +1221,32 @@ int server_raw_recv(iphdr * iph,tcphdr *tcph,char * data,int data_len)
printf("unexpected adress\n");
return 0;
}
if(data_len!=sizeof(session_id)*2+1||data[0]!='h')
if(data_len!=sizeof(my_id)*2+1||data[0]!='h')
{
return 0;
}
uint32_t tmp_session_id= ntohl(* ((uint32_t *)&data[1+sizeof(my_id)]));
uint32_t tmp_session_id= ntohl(* ((uint32_t *)&data[1+sizeof(session_id)]));
printf("received hb %x %x\n",oppsite_id,tmp_session_id);
printf("received hb %x %x\n",oppsite_session_id,tmp_session_id);
if(tmp_session_id!=session_id)
if(tmp_session_id!=my_id)
{
printf("auth fail!!\n");
return 0;
}
int tmp_oppsite_session_id= ntohl(* ((uint32_t *)&data[1]));
if(tmp_oppsite_session_id!=oppsite_session_id)
{
struct epoll_event ev;
oppsite_id=tmp_oppsite_session_id;
if(udp_fd!=-1)
{
int ret = epoll_ctl(epollfd, EPOLL_CTL_DEL, udp_fd, 0);
close(udp_fd);
udp_fd=-1;
}
oppsite_session_id=tmp_oppsite_session_id;
//anti_replay.re_init();
}
//anti_replay.enable();
//session_id=get_true_random_number();
send_hb(g_packet_info,my_id,oppsite_id);
server_current_state=server_ready;
last_state_time=get_current_time();
last_hb_recv_time=get_current_time();
first_data_packet=1;
printf("changed state to server_ready\n");
}
@ -1233,35 +1259,43 @@ int server_raw_recv(iphdr * iph,tcphdr *tcph,char * data,int data_len)
return 0;
}
if(data[0]=='h'&&data_len==sizeof(session_id)*2+1)
if(data[0]=='h'&&data_len==sizeof(my_id)*2+1)
{
uint32_t tmp= ntohl(* ((uint32_t *)&data[1+sizeof(uint32_t)]));
if(debug_mode)printf("received hb <%x,%x>\n",oppsite_session_id,tmp);
if(debug_mode)printf("received hb <%x,%x>\n",oppsite_id,tmp);
last_hb_recv_time=get_current_time();
}
else if(data[0]=='d'&&data_len>=sizeof(session_id)*2+1)
else if(data[0]=='d'&&data_len>=sizeof(my_id)*3+1)
{
uint32_t tmp_oppsite_session_id=ntohl(* ((uint32_t *)&data[1]));
uint32_t tmp_session_id=ntohl(* ((uint32_t *)&data[1+sizeof(session_id)]));
uint32_t tmp_session_id=ntohl(* ((uint32_t *)&data[1+sizeof(my_id)]));
uint32_t tmp_conv_id=ntohl(* ((uint32_t *)&data[1+sizeof(my_id)*2]));
if(tmp_session_id!=session_id)
if(tmp_session_id!=my_id)
{
printf("server session id mismatch,ignore\n");
printf("my id mismatch,ignore\n");
return 0;
}
if(tmp_oppsite_session_id!=oppsite_session_id) //magic to find out which one is actually larger
//consider 0xffffffff+1= 0x0 ,in this case 0x0 is "actually" larger
if(tmp_oppsite_session_id!=oppsite_id)
{
printf("oppsite id mismatch,ignore\n");
return 0;
}
if(first_data_packet==0&& tmp_conv_id!=conv_id) //magic to find out which one is actually larger
//consider 0xffffffff+1= 0x0 ,in this case 0x0 is "actually" larger
{
uint32_t smaller,bigger;
smaller=min(oppsite_session_id,tmp_oppsite_session_id);//smaller in normal sense
bigger=max(oppsite_session_id,tmp_oppsite_session_id);
smaller=min(conv_id,tmp_conv_id);//smaller in normal sense
bigger=max(conv_id,tmp_conv_id);
uint32_t distance=min(bigger-smaller,smaller+(0xffffffff-bigger+1));
if(distance==bigger-smaller)
{
if(bigger==oppsite_session_id) //received_session_id is acutally bigger
if(bigger==conv_id) //received_session_id is acutally bigger
{
printf("old_session_id ,ingored1\n");
return 0;
@ -1269,16 +1303,16 @@ int server_raw_recv(iphdr * iph,tcphdr *tcph,char * data,int data_len)
}
else
{
if(smaller==oppsite_session_id) //received_session_id is acutally bigger
if(smaller==conv_id) //received_session_id is acutally bigger
{
printf("old_session_id ,ingored2\n");
return 0;
}
}
}
first_data_packet=0;
if(udp_fd==-1||tmp_oppsite_session_id!=oppsite_session_id)// this is first send or client changed session
if(udp_fd==-1||tmp_conv_id!=conv_id)// this is first send or client changed session
{
int old_fd=udp_fd;
@ -1319,18 +1353,21 @@ int server_raw_recv(iphdr * iph,tcphdr *tcph,char * data,int data_len)
}
if(tmp_oppsite_session_id!=oppsite_session_id)
if(tmp_conv_id!=conv_id)
{
oppsite_session_id=tmp_oppsite_session_id;
printf("created new udp_fd");
conv_id=tmp_conv_id;
}
printf("received a data from fake tcp,len:%d\n",data_len);
last_hb_recv_time=get_current_time();
int ret=send(udp_fd,data+1+sizeof(session_id)*2,data_len -(1+sizeof(session_id)*2),0);
int ret=send(udp_fd,data+1+sizeof(my_id)*3,data_len -(1+sizeof(my_id)*3),0);
printf("%d byte sent\n",ret);
}
}
}
int on_raw_recv()
{
int size;
@ -1499,7 +1536,8 @@ int client()
{
int i, j, k;int ret;
init_raw_socket();
session_id=get_true_random_number();
my_id=get_true_random_number();
conv_id=get_true_random_number();
//init_filter(source_port);
g_packet_info.dst_ip=inet_addr(remote_address);
@ -1605,7 +1643,6 @@ int client()
exit(1);
};
printf("Received packet from %s:%d,len: %d\n", inet_ntoa(udp_new_addr_in.sin_addr),
ntohs(udp_new_addr_in.sin_port),recv_len);
@ -1625,14 +1662,14 @@ int client()
{
printf("new <ip,port> connected in,accpeted\n");
memcpy(&udp_old_addr_in,&udp_new_addr_in,sizeof(udp_new_addr_in));
session_id=session_id+1;
conv_id++;
}
}
last_udp_recv_time=get_current_time();
if(client_current_state=client_ready)
{
send_data(g_packet_info,buf,recv_len,session_id,oppsite_session_id);
send_data(g_packet_info,buf,recv_len,my_id,oppsite_id,conv_id);
}
////send_data_raw(buf,recv_len);
}
@ -1714,7 +1751,7 @@ int server()
continue;
//return 0;
}
send_data(g_packet_info,buf,recv_len,session_id,oppsite_session_id);
send_data(g_packet_info,buf,recv_len,my_id,oppsite_id,conv_id);
}
//printf("%d %d %d %d\n",timer_fd,raw_recv_fd,raw_send_fd,n);
if (events[n].data.u64 == epoll_timer_fd_sn)