sad/udp2raw
1
0
Fork 0
mirror of https://github.com/wangyu-/udp2raw.git synced 2024-06-16 03:59:13 +00:00
Code Issues Packages Projects Releases Wiki Activity

avoid MSG_PEEK

Browse Source
This commit is contained in:
wangyu- 2018-07-21 14:23:13 -05:00
parent 1e98ae10c2
commit 9e9ad56890
3 changed files with 86 additions and 24 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

18
main.cpp
View File

@ -304,10 +304,13 @@ int client_on_raw_recv(conn_info_t &conn_info) //called when raw fd received a p
raw_info_t &raw_info=conn_info.raw_info;
mylog(log_trace,"<client_on_raw_recv,send_info.ts_ack= %u>\n",send_info.ts_ack);
if(pre_recv_raw_packet()<0) return -1;
if(conn_info.state.client_current_state==client_idle )
{
recv(raw_recv_fd, 0,0, 0 );
discard_raw_packet();
//recv(raw_recv_fd, 0,0, 0 );
}
else if(conn_info.state.client_current_state==client_tcp_handshake)//received syn ack
{
@ -988,9 +991,11 @@ int server_on_raw_recv_multi() //called when server received an raw packet
{
char dummy_buf[buf_len];
packet_info_t peek_info;
if(pre_recv_raw_packet()<0) return -1;
if(peek_raw(peek_info)<0)
{
recv(raw_recv_fd, 0,0, 0 );//
discard_raw_packet();
//recv(raw_recv_fd, 0,0, 0 );//
//struct sockaddr saddr;
//socklen_t saddr_size=sizeof(saddr);
///recvfrom(raw_recv_fd, 0,0, 0 ,&saddr , &saddr_size);//
@ -1052,7 +1057,8 @@ int server_on_raw_recv_multi() //called when server received an raw packet
}
else
{
recv(raw_recv_fd, 0,0,0);
discard_raw_packet();
//recv(raw_recv_fd, 0,0,0);
}
return 0;
}
@ -1061,7 +1067,8 @@ int server_on_raw_recv_multi() //called when server received an raw packet
if(conn_manager.mp.size()>=max_handshake_conn_num)
{
mylog(log_info,"[%s]reached max_handshake_conn_num,ignored new handshake\n",ip_port);
recv(raw_recv_fd, 0,0, 0 );//
discard_raw_packet();
//recv(raw_recv_fd, 0,0, 0 );//
return 0;
}
@ -1162,7 +1169,8 @@ int server_on_raw_recv_multi() //called when server received an raw packet
if(conn_info.state.server_current_state==server_idle)
{
recv(raw_recv_fd, 0,0, 0 );//
discard_raw_packet();
//recv(raw_recv_fd, 0,0, 0 );//
return 0;
}
mylog(log_fatal,"we should never run to here\n");

85
network.cpp
View File

@ -40,6 +40,18 @@ const u32_t receive_window_lower_bound=40960;
const u32_t receive_window_random_range=512;
const unsigned char wscale=0x05;
char g_packet_buf[buf_len]; //looks dirty but works well
int g_packet_buf_len=-1;
int g_packet_buf_cnt=0;
union
{
sockaddr_ll ll;
sockaddr_in ipv4;
sockaddr_in6 ipv6;
}g_sockaddr;
socklen_t g_sockaddr_len = -1;
struct sock_filter code_tcp_old[] = {
{ 0x28, 0, 0, 0x0000000c },//0
{ 0x15, 0, 10, 0x00000800 },//1
@ -178,7 +190,7 @@ int init_raw_socket()
g_ip_id_counter=get_true_random_number()%65535;
if(lower_level==0)
{
raw_send_fd = socket(AF_INET , SOCK_RAW , IPPROTO_TCP);
raw_send_fd = socket(AF_INET , SOCK_RAW , IPPROTO_TCP);// IPPROTO_TCP??
if(raw_send_fd == -1) {
mylog(log_fatal,"Failed to create raw_send_fd\n");
@ -198,7 +210,7 @@ int init_raw_socket()
}
else
{
raw_send_fd = socket(PF_PACKET , SOCK_DGRAM , htons(ETH_P_IP));
raw_send_fd = socket(PF_PACKET , SOCK_DGRAM , htons(ETH_P_IP));// todo how to create a recv only raw socket?
if(raw_send_fd == -1) {
mylog(log_fatal,"Failed to create raw_send_fd\n");
@ -231,6 +243,9 @@ int init_raw_socket()
//raw_fd = socket(AF_PACKET, SOCK_DGRAM, htons(ETH_P_ALL));
raw_recv_fd= socket(PF_PACKET, SOCK_DGRAM, htons(ETH_P_IP));
//ETH_P_IP doesnt read outgoing packets
// https://stackoverflow.com/questions/20264895/eth-p-ip-is-not-working-as-expected-i-can-only-receive-incoming-packets
// to capture both incoming and outgoing packets use ETH_P_ALL
if(raw_recv_fd == -1) {
mylog(log_fatal,"Failed to create raw_recv_fd\n");
@ -661,11 +676,17 @@ int send_raw_ip(raw_info_t &raw_info,const char * payload,int payloadlen)
return 0;
}
int peek_raw(packet_info_t &peek_info)
{ static char peek_raw_buf[buf_len];
{
//static char peek_raw_buf[buf_len];
assert(g_packet_buf_cnt==1);
//g_packet_buf_cnt--;
char * peek_raw_buf=g_packet_buf;
int recv_len=g_packet_buf_len;
char *ip_begin=peek_raw_buf+link_level_header_len;
struct sockaddr saddr={0};
socklen_t saddr_size=sizeof(saddr);
int recv_len = recvfrom(raw_recv_fd, peek_raw_buf,max_data_len, MSG_PEEK ,&saddr , &saddr_size);//change max_data_len to something smaller,we only need header here
//struct sockaddr saddr={0};
//socklen_t saddr_size=sizeof(saddr);
//int recv_len = recvfrom(raw_recv_fd, peek_raw_buf,max_data_len, MSG_PEEK ,&saddr , &saddr_size);//change max_data_len to something smaller,we only need header here
iphdr * iph = (struct iphdr *) (ip_begin);
//mylog(log_info,"recv_len %d\n",recv_len);
if(recv_len<int(sizeof(iphdr)))
@ -720,30 +741,56 @@ int peek_raw(packet_info_t &peek_info)
}
return 0;
}
int recv_raw_ip(raw_info_t &raw_info,char * &payload,int &payloadlen)
int pre_recv_raw_packet()
{
const packet_info_t &send_info=raw_info.send_info;
packet_info_t &recv_info=raw_info.recv_info;
assert(g_packet_buf_cnt==0);
static char recv_raw_ip_buf[buf_len];
g_sockaddr_len=sizeof(g_sockaddr.ll);
g_packet_buf_len = recvfrom(raw_recv_fd, g_packet_buf, max_data_len+1, 0 ,(sockaddr*)&g_sockaddr , &g_sockaddr_len);
//assert(g_sockaddr_len==sizeof(g_sockaddr.ll)); //g_sockaddr_len=18, sizeof(g_sockaddr.ll)=20, why its not equal? maybe its bc sll_halen is 6?
iphdr * iph;
struct sockaddr_ll saddr={0};
socklen_t saddr_size = sizeof(saddr);
int flag=0;
int recv_len = recvfrom(raw_recv_fd, recv_raw_ip_buf, max_data_len+1, flag ,(sockaddr*)&saddr , &saddr_size);
//assert(g_addr_ll_size==sizeof(g_addr_ll));
if(recv_len==max_data_len+1)
if(g_packet_buf_len==max_data_len+1)
{
mylog(log_warn,"huge packet, data_len > %d,dropped\n",max_data_len);
return -1;
}
if(recv_len<0)
if(g_packet_buf_len<0)
{
mylog(log_trace,"recv_len %d\n",recv_len);
mylog(log_trace,"recv_len %d\n",g_packet_buf_len);
return -1;
}
g_packet_buf_cnt++;
return 0;
}
int discard_raw_packet()
{
assert(g_packet_buf_cnt==1);
g_packet_buf_cnt--;
return 0;
}
int recv_raw_ip(raw_info_t &raw_info,char * &payload,int &payloadlen)
{
assert(g_packet_buf_cnt==1);
g_packet_buf_cnt--;
char *recv_raw_ip_buf=g_packet_buf;
//static char recv_raw_ip_buf[buf_len];
int recv_len=g_packet_buf_len;
const packet_info_t &send_info=raw_info.send_info;
packet_info_t &recv_info=raw_info.recv_info;
iphdr * iph;
int flag=0;
//int recv_len = recvfrom(raw_recv_fd, recv_raw_ip_buf, max_data_len+1, flag ,(sockaddr*)&saddr , &saddr_size);
if(recv_len<int(link_level_header_len))
{
mylog(log_trace,"length error\n");
@ -766,7 +813,7 @@ int recv_raw_ip(raw_info_t &raw_info,char * &payload,int &payloadlen)
if(lower_level)
{
memcpy(&recv_info.addr_ll,&saddr,sizeof(recv_info.addr_ll));
memcpy(&recv_info.addr_ll,&g_sockaddr.ll,sizeof(recv_info.addr_ll));
}

7
network.h
View File

@ -26,6 +26,10 @@ extern int random_drop;
extern int ifindex;
extern char g_packet_buf[buf_len];
extern int g_packet_buf_len;
extern int g_packet_buf_cnt;
struct icmphdr
{
uint8_t type;
@ -108,6 +112,9 @@ int try_to_list_and_bind(int & bind_fd,u32_t local_ip_uint32,int port); //try t
int client_bind_to_a_new_port(int & bind_fd,u32_t local_ip_uint32);//find a free port and bind to it.
int client_bind_to_a_new_port2(int &fd,const address_t& address);
int discard_raw_packet();
int pre_recv_raw_packet();
int send_raw_ip(raw_info_t &raw_info,const char * payload,int payloadlen);
int peek_raw(packet_info_t &peek_info);