/* For a given TCP connection, if we have all the bytes we want, do the
* next thing */
void tcp_process_data(int b) {
int32_t wanted = 0;
if(tcp_pend[b].wanted != tcp_pend[b].got || tcp_pend[b].buffer == 0
|| tcp_pend[b].state != 0) {
return;
}
if(tcp_pend[b].wanted == 2) { /* If we wanted the length of the DNS
* packet */
/* Based on the length of the DNS packet wanted, we next
* try to get the DNS packet */
tcp_pend[b].got = 0;
wanted = tcp_pend[b].buffer[0];
wanted <<= 8;
wanted |= tcp_pend[b].buffer[1];
free(tcp_pend[b].buffer);
tcp_pend[b].buffer = 0;
if(wanted < 12) {
closesocket(tcp_pend[b].local);
reset_tcp_pend(b);
return;
}
tcp_pend[b].wanted = wanted;
tcp_pend[b].buffer = malloc(wanted + 1);
tcp_pend[b].die = get_time() +
((int64_t)timeout_seconds_tcp << 8);
} else if(tcp_pend[b].wanted >= 12) {
tcp_to_udp(b);
}
}
int main(int argc, char *argv[])
{
struct relay *relays;
int relay_count, is_server;
int i;
fd_set readfds;
int max = 0;
int ok;
parse_args(argc, argv, &relays, &relay_count, &is_server);
for (i = 0; i < relay_count; i++) {
if (is_server) {
setup_server_listen(&relays[i]);
}
else {
setup_tcp_client(&relays[i]);
}
setup_udp_recv(&relays[i]);
setup_udp_send(&relays[i]);
}
if (is_server) {
await_incoming_connections(relays, relay_count);
}
do {
FD_ZERO(&readfds);
for (i = 0; i < relay_count; i++) {
FD_SET(relays[i].tcp_sock, &readfds);
SET_MAX(relays[i].tcp_sock);
FD_SET(relays[i].udp_recv_sock, &readfds);
SET_MAX(relays[i].udp_recv_sock);
}
if (select(max, &readfds, NULL, NULL, NULL) < 0) {
if (errno != EINTR) {
perror("main loop: select");
exit(1);
}
}
ok = 0;
for (i = 0; i < relay_count; i++) {
if (FD_ISSET(relays[i].tcp_sock, &readfds)) {
ok += tcp_to_udp(&relays[i]);
}
if (FD_ISSET(relays[i].udp_recv_sock, &readfds)) {
ok += udp_to_tcp(&relays[i]);
}
}
} while (ok == 0);
exit(0);
} /* main */
