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|
package main
import (
"errors"
"log"
"net"
"os"
"os/signal"
"sync"
"syscall"
"github.com/anon55555/mt"
)
func main() {
if err := loadConfig(); err != nil {
log.Fatal("{←|⇶} ", err)
}
var err error
switch conf.AuthBackend {
case "sqlite3":
authIface = authSQLite3{}
default:
log.Fatal("{←|⇶} invalid auth backend")
}
addr, err := net.ResolveUDPAddr("udp", conf.BindAddr)
if err != nil {
log.Fatal("{←|⇶} ", err)
}
pc, err := net.ListenUDP("udp", addr)
if err != nil {
log.Fatal("{←|⇶} ", err)
}
l := listen(pc)
defer l.close()
log.Print("{←|⇶} listen ", l.addr())
clts := make(map[*clientConn]struct{})
var mu sync.Mutex
go func() {
sig := make(chan os.Signal)
signal.Notify(sig, os.Interrupt, syscall.SIGTERM, syscall.SIGHUP)
<-sig
l.close()
mu.Lock()
defer mu.Unlock()
var wg sync.WaitGroup
wg.Add(len(clts))
for cc := range clts {
go func() {
ack, _ := cc.SendCmd(&mt.ToCltDisco{Reason: mt.Shutdown})
select {
case <-cc.Closed():
case <-ack:
cc.Close()
}
wg.Done()
}()
}
wg.Wait()
os.Exit(0)
}()
for {
cc, err := l.accept()
if err != nil {
if errors.Is(err, net.ErrClosed) {
log.Print("{←|⇶} stop listening")
break
}
log.Print("{←|⇶} ", err)
continue
}
mu.Lock()
clts[cc] = struct{}{}
mu.Unlock()
go func() {
<-cc.Closed()
mu.Lock()
defer mu.Unlock()
delete(clts, cc)
}()
go func() {
<-cc.init()
cc.log("<->", "handshake completed")
if len(conf.Servers) == 0 {
cc.log("<--", "no servers")
ack, _ := cc.SendCmd(&mt.ToCltDisco{
Reason: mt.Custom,
Custom: "No servers are configured.",
})
select {
case <-cc.Closed():
case <-ack:
cc.Close()
}
return
}
addr, err := net.ResolveUDPAddr("udp", conf.Servers[0].Addr)
if err != nil {
cc.log("<--", "address resolution fail")
ack, _ := cc.SendCmd(&mt.ToCltDisco{
Reason: mt.Custom,
Custom: "Server address resolution failed.",
})
select {
case <-cc.Closed():
case <-ack:
cc.Close()
}
return
}
conn, err := net.DialUDP("udp", nil, addr)
if err != nil {
cc.log("<--", "connection fail")
ack, _ := cc.SendCmd(&mt.ToCltDisco{
Reason: mt.Custom,
Custom: "Server connection failed.",
})
select {
case <-cc.Closed():
case <-ack:
cc.Close()
}
return
}
connect(conn, cc)
}()
}
select {}
}
|
