github/wangyu-udp2raw
1
0
Fork 0
mirror of https://github.com/wangyu-/udp2raw.git synced 2025-01-19 14:29:34 +08:00
Code Issues Packages Projects Releases Wiki Activity

added some comment

Browse Source
This commit is contained in:
wangyu- 2017-08-27 03:31:22 -05:00
parent 01a1d2b006
commit 1f94c40ccf
1 changed files with 71 additions and 62 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

133
main.cpp
View File

@ -9,48 +9,50 @@
#include <map>
#include <set>
char local_ip[100]="0.0.0.0", remote_ip[100]="255.255.255.255",source_ip[100]="0.0.0.0";
u32_t local_ip_uint32,remote_ip_uint32,source_ip_uint32;
char local_ip[100]="0.0.0.0", remote_ip[100]="255.255.255.255",source_ip[100]="0.0.0.0";//local_ip is for -l option,remote_ip for -r option,source for --source-ip
u32_t local_ip_uint32,remote_ip_uint32,source_ip_uint32;//convert from last line.
int local_port = -1, remote_port=-1,source_port=0;//similiar to local_ip remote_ip,buf for port.source_port=0 indicates --source-port is not enabled
int force_source_ip=0;
int source_port=0,local_port = -1, remote_port = -1;
id_t const_id=0;
int force_source_ip=0; //if --source-ip is enabled
const int disable_conv_clear=0;
const int disable_conn_clear=0;
id_t const_id=0;//an id used for connection recovery,its generated randomly,it never change since its generated
enum server_current_state_t {server_idle=0,server_handshake1,server_ready};
enum client_current_state_t {client_idle=0,client_tcp_handshake,client_handshake1,client_handshake2,client_ready};
const int disable_conv_clear=0;//a udp connection in the multiplexer is called conversation in this program,conv for short.
const int disable_conn_clear=0;//a raw connection is called conn.
enum server_current_state_t {server_idle=0,server_handshake1,server_ready}; //server state machine
enum client_current_state_t {client_idle=0,client_tcp_handshake,client_handshake1,client_handshake2,client_ready};//client state machine
union current_state_t
{
server_current_state_t server_current_state;
client_current_state_t client_current_state;
};
int udp_fd=-1; //for client only
int bind_fd=-1; //bind only,never send or recv
int epollfd=-1;
int timer_fd=-1;
int fail_time_counter=0;
int epoll_trigger_counter=0;
int debug_flag=0;
int udp_fd=-1; //for client only. client use this fd to listen and handle udp connection
int bind_fd=-1; //bind only,never send or recv. its just a dummy fd for bind,so that other program wont occupy the same port
int epollfd=-1; //fd for epoll
int timer_fd=-1; //the general timer fd for client and server.for server this is not the only timer find,every connection has a timer fd.
int fail_time_counter=0;//determine if the max_fail_time is reached
int epoll_trigger_counter=0;//for debug only
int debug_flag=0;//for debug only
int simple_rule=0;
int keep_rule=0;
int auto_add_iptables_rule=0;
int generate_iptables_rule=0;
int generate_iptables_rule_add=0;
int simple_rule=0; //deprecated.
int keep_rule=0; //whether to monitor the iptables rule periodly,re-add if losted
int auto_add_iptables_rule=0;//if -a is set
int generate_iptables_rule=0;//if -g is set
int generate_iptables_rule_add=0;// if --gen-add is set
int debug_resend=0;
int disable_anti_replay=0;
char key_string[1000]= "secret key";
char key[16];//,key2[16];
int debug_resend=0; // debug only
int disable_anti_replay=0;//if anti_replay windows is diabled
char key_string[1000]= "secret key";// -k option
char key[16];//generated from key_string by md5.
int mtu_warn=1375;
int mtu_warn=1375;//if a packet larger than mtu warn is receviced,there will be a warning
//uint64_t current_time_rough=0;
@ -58,7 +60,7 @@ int mtu_warn=1375;
int VVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVV;
////////==============================variable divider=============================================================
struct anti_replay_t
struct anti_replay_t //its for anti replay attack,similar to openvpn/ipsec 's anti replay window
{
u64_t max_packet_received;
char window[anti_replay_window_size];
@ -121,7 +123,7 @@ struct anti_replay_t
};//anti_replay;
void server_clear_function(u64_t u64);
struct conv_manager_t //TODO change map to unordered map
struct conv_manager_t // manage the udp connections
{
//typedef hash_map map;
unordered_map<u64_t,u32_t> u64_to_conv; //conv and u64 are both supposed to be uniq
@ -284,12 +286,13 @@ struct conv_manager_t //TODO change map to unordered map
return 0;
}
};//g_conv_manager;
struct blob_t
struct blob_t //used in conn_info_t. conv_manager_t and anti_replay_t are costly data structures ,we dont allocate them until its necessary
{
conv_manager_t conv_manager;
anti_replay_t anti_replay;
};
struct conn_info_t
struct conn_info_t //stores info for a raw connection.for client ,there is only one connection,for server there can be thousand of connection since server can
//handle multiple clients
{
current_state_t state;
@ -376,7 +379,7 @@ struct conn_info_t
~conn_info_t();
};//g_conn_info;
struct conn_manager_t
struct conn_manager_t //manager for connections. for client,we dont need conn_manager since there is only one connection.for server we use one conn_manager for all connections
{
u32_t ready_num;
@ -580,7 +583,8 @@ int find_lower_level_info(u32_t ip,u32_t &dest_ip,string &if_name,string &hw);
int DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD;
////////////////=======================declear divider=============================
void server_clear_function(u64_t u64)
void server_clear_function(u64_t u64)//used in conv_manager in server mode.for server we have to use one udp fd for one conv(udp connection),
//so we have to close the fd when conv expires
{
int fd=int(u64);
int ret;
@ -612,7 +616,8 @@ void server_clear_function(u64_t u64)
int send_bare(raw_info_t &raw_info,const char* data,int len)
int send_bare(raw_info_t &raw_info,const char* data,int len)//send function with encryption but no anti replay,this is used when client and server verifys each other
//you have to design the protocol carefully, so that you wont be affect by relay attack
{
if(len<0)
{
@ -644,7 +649,7 @@ int send_bare(raw_info_t &raw_info,const char* data,int len)
send_raw0(raw_info,send_data_buf2,new_len);
return 0;
}
int parse_bare(const char *input,int input_len,char* & data,int & len) //allow overlap
int parse_bare(const char *input,int input_len,char* & data,int & len) // a sub function used in recv_bare
{
static char recv_data_buf[buf_len];
@ -673,7 +678,8 @@ int parse_bare(const char *input,int input_len,char* & data,int & len) //allow
}
return 0;
}
int recv_bare(raw_info_t &raw_info,char* & data,int & len)
int recv_bare(raw_info_t &raw_info,char* & data,int & len)//recv function with encryption but no anti replay,this is used when client and server verifys each other
//you have to design the protocol carefully, so that you wont be affect by relay attack
{
packet_info_t &send_info=raw_info.send_info;
packet_info_t &recv_info=raw_info.recv_info;
@ -691,7 +697,7 @@ int recv_bare(raw_info_t &raw_info,char* & data,int & len)
return parse_bare(data,len,data,len);
}
int send_handshake(raw_info_t &raw_info,id_t id1,id_t id2,id_t id3)
int send_handshake(raw_info_t &raw_info,id_t id1,id_t id2,id_t id3)// a warp for send_bare for sending handshake(this is not tcp handshake) easily
{
packet_info_t &send_info=raw_info.send_info;
packet_info_t &recv_info=raw_info.recv_info;
@ -713,7 +719,7 @@ int recv_handshake(packet_info_t &info,id_t &id1,id_t &id2,id_t &id3)
return 0;
}*/
int send_safer(conn_info_t &conn_info,char type,const char* data,int len)
int send_safer(conn_info_t &conn_info,char type,const char* data,int len) //safer transfer function with anti-replay,when mutually verification is done.
{
packet_info_t &send_info=conn_info.raw_info.send_info;
@ -763,7 +769,7 @@ int send_safer(conn_info_t &conn_info,char type,const char* data,int len)
return 0;
}
int send_data_safer(conn_info_t &conn_info,const char* data,int len,u32_t conv_num)
int send_data_safer(conn_info_t &conn_info,const char* data,int len,u32_t conv_num)//a wrap for send_safer for transfer data.
{
packet_info_t &send_info=conn_info.raw_info.send_info;
packet_info_t &recv_info=conn_info.raw_info.recv_info;
@ -779,7 +785,7 @@ int send_data_safer(conn_info_t &conn_info,const char* data,int len,u32_t conv_n
return 0;
}
int parse_safer(conn_info_t &conn_info,const char * input,int input_len,char &type,char* &data,int &len)//allow overlap
int parse_safer(conn_info_t &conn_info,const char * input,int input_len,char &type,char* &data,int &len)//subfunction for recv_safer,allow overlap
{
static char recv_data_buf0[buf_len];
@ -846,7 +852,7 @@ int parse_safer(conn_info_t &conn_info,const char * input,int input_len,char &ty
return 0;
}
int recv_safer(conn_info_t &conn_info,char &type,char* &data,int &len)
int recv_safer(conn_info_t &conn_info,char &type,char* &data,int &len)///safer transfer function with anti-replay,when mutually verification is done.
{
packet_info_t &send_info=conn_info.raw_info.send_info;
packet_info_t &recv_info=conn_info.raw_info.recv_info;
@ -859,7 +865,7 @@ int recv_safer(conn_info_t &conn_info,char &type,char* &data,int &len)
return parse_safer(conn_info,recv_data,recv_len,type,data,len);
}
int try_to_list_and_bind(int port)
int try_to_list_and_bind(int port) //try to bind to a port,may fail.
{
int old_bind_fd=bind_fd;
@ -898,7 +904,7 @@ int try_to_list_and_bind(int port)
}
return 0;
}
int client_bind_to_a_new_port()
int client_bind_to_a_new_port()//find a free port and bind to it.
{
int raw_send_port=10000+get_true_random_number()%(65535-10000);
for(int i=0;i<1000;i++)//try 1000 times at max,this should be enough
@ -915,7 +921,7 @@ int client_bind_to_a_new_port()
int set_timer(int epollfd,int &timer_fd)
int set_timer(int epollfd,int &timer_fd)//put a timer_fd into epoll,general function,used both in client and server
{
int ret;
epoll_event ev;
@ -946,7 +952,7 @@ int set_timer(int epollfd,int &timer_fd)
}
int set_timer_server(int epollfd,int &timer_fd)
int set_timer_server(int epollfd,int &timer_fd)//only for server
{
int ret;
epoll_event ev;
@ -976,7 +982,7 @@ int set_timer_server(int epollfd,int &timer_fd)
return 0;
}
int get_src_adress(u32_t &ip);
int client_on_timer(conn_info_t &conn_info) //for client
int client_on_timer(conn_info_t &conn_info) //for client. called when a timer is ready in epoll
{
//keep_iptables_rule();
packet_info_t &send_info=conn_info.raw_info.send_info;
@ -1216,7 +1222,8 @@ int client_on_timer(conn_info_t &conn_info) //for client
}
return 0;
}
int server_on_timer_multi(conn_info_t &conn_info,char * ip_port)
int server_on_timer_multi(conn_info_t &conn_info,char * ip_port) //for server. called when a timer is ready in epoll.for server,there will be one timer for every connection
{
//keep_iptables_rule();
mylog(log_trace,"server timer!\n");
@ -1260,7 +1267,7 @@ int server_on_timer_multi(conn_info_t &conn_info,char * ip_port)
return 0;
}
int client_on_raw_recv(conn_info_t &conn_info)
int client_on_raw_recv(conn_info_t &conn_info) //called when raw fd received a packet.
{
char* data;int data_len;
packet_info_t &send_info=conn_info.raw_info.send_info;
@ -1440,7 +1447,7 @@ int client_on_raw_recv(conn_info_t &conn_info)
}
return 0;
}
int handle_lower_level(raw_info_t &raw_info)
int handle_lower_level(raw_info_t &raw_info)//fill lower_level info,when --lower-level is enabled,only for server
{
packet_info_t &send_info=raw_info.send_info;
packet_info_t &recv_info=raw_info.recv_info;
@ -1469,7 +1476,7 @@ int handle_lower_level(raw_info_t &raw_info)
}
return 0;
}
int server_on_raw_recv_multi()
int server_on_raw_recv_multi() //called when server received an raw packet
{
char dummy_buf[buf_len];
packet_info_t peek_info;
@ -1639,7 +1646,7 @@ int server_on_raw_recv_handshake1(conn_info_t &conn_info,id_t tmp_oppsite_id )
return 0;
}*/
int server_on_raw_recv_handshake1(conn_info_t &conn_info,char * ip_port,char * data, int data_len)
int server_on_raw_recv_handshake1(conn_info_t &conn_info,char * ip_port,char * data, int data_len)//called when server received a handshake1 packet from client
{
packet_info_t &send_info=conn_info.raw_info.send_info;
packet_info_t &recv_info=conn_info.raw_info.recv_info;
@ -1701,7 +1708,8 @@ int server_on_raw_recv_handshake1(conn_info_t &conn_info,char * ip_port,char * d
}
return 0;
}
int server_on_raw_recv_ready(conn_info_t &conn_info,char * ip_port,char type,char *data,int data_len)
int server_on_raw_recv_ready(conn_info_t &conn_info,char * ip_port,char type,char *data,int data_len) //called while the state for a connection is server_ready
//receives data and heart beat by recv_safer.
{
raw_info_t &raw_info = conn_info.raw_info;
@ -1813,7 +1821,8 @@ int server_on_raw_recv_ready(conn_info_t &conn_info,char * ip_port,char type,cha
return 0;
}
int server_on_raw_recv_pre_ready(conn_info_t &conn_info,char * ip_port,u32_t tmp_oppsite_const_id)
int server_on_raw_recv_pre_ready(conn_info_t &conn_info,char * ip_port,u32_t tmp_oppsite_const_id)// do prepare work before state change to server ready for a specifc connection
//connection recovery is also handle here
{
//u32_t ip;uint16_t port;
//ip=conn_info.raw_info.recv_info.src_ip;
@ -1931,7 +1940,7 @@ int server_on_raw_recv_pre_ready(conn_info_t &conn_info,char * ip_port,u32_t tmp
return 0;
}
int get_src_adress(u32_t &ip)
int get_src_adress(u32_t &ip) //a trick to get src adress for a dest adress,so that we can use the src address in raw socket as source ip
{
struct sockaddr_in remote_addr_in={0};
@ -2497,7 +2506,7 @@ int server_event_loop()
return 0;
}
//char lower_level_arg[1000];
int process_lower_level_arg()
int process_lower_level_arg()//handle --lower-level option
{
lower_level=1;
if(strcmp(optarg,"auto")==0)
@ -2552,7 +2561,7 @@ void print_help()
printf(" this option disables port changing while re-connecting\n");
// printf(" \n");
printf("other options:\n");
printf(" --conf-file <string> read options from a configuration file instead of command line\n");
printf(" --conf-file <string> read options from a configuration file instead of command line.\n");
printf(" check example.conf in repo for format\n");
printf(" --log-level <number> 0:never 1:fatal 2:error 3:warn \n");
printf(" 4:info (default) 5:debug 6:trace\n");
@ -2579,7 +2588,7 @@ void print_help()
//printf("common options,these options must be same on both side\n");
}
int load_config(char *file_name, int &argc, vector<string> &argv)
int load_config(char *file_name, int &argc, vector<string> &argv) //load conf file and append to argv
{
// Load configurations from config_file instead of the command line.
// See config.example for example configurations
@ -2622,7 +2631,7 @@ int unit_test()
return 0;
}
int process_log_level(int argc,char *argv[])
int process_log_level(int argc,char *argv[])//process --log-level and --disable-cloer --log-postion options
{
int i,j,k;
for (i = 0; i < argc; i++)
@ -2653,7 +2662,7 @@ int process_log_level(int argc,char *argv[])
}
return 0;
}
void process_arg(int argc, char *argv[])
void process_arg(int argc, char *argv[]) //process all options
{
int i,j,k,opt;
@ -3052,7 +3061,7 @@ void process_arg(int argc, char *argv[])
log_bare(log_info,"\n");
}
void pre_process_arg(int argc, char *argv[])
void pre_process_arg(int argc, char *argv[])//mainly for load conf file
{
int i,j,k;
for (i = 0; i < argc; i++)
@ -3139,7 +3148,7 @@ void pre_process_arg(int argc, char *argv[])
process_arg(new_argc,new_argv_char);
}
void *run_keep(void *none)
void *run_keep(void *none) //called in a new thread for --keep-rule option
{
while(1)
@ -3156,7 +3165,7 @@ void *run_keep(void *none)
return NULL;
}
void iptables_rule()
void iptables_rule() // handles -a -g --gen-add --keep-rule
{
if(auto_add_iptables_rule&&generate_iptables_rule)
{