STRLCPY/tun2socks

Refactor: remove nat pkg
xjasonlyu committed 11 months ago

9dfea44f

1 parent 860cf312

■ ■ ■ ■ ■ ■

component/nat/nat.go

1	-	/*
2	-	Package nat provides simple NAT table implements.
3	-
4	-	* Normal (Full Cone) NAT
5	-	A full cone NAT is one where all requests from the same internal IP address
6	-	and port are mapped to the same external IP address and port. Furthermore,
7	-	any external host can send a packet to the internal host, by sending a packet
8	-	to the mapped external address.
9	-
10	-	* Restricted Cone NAT
11	-	A restricted cone NAT is one where all requests from the same internal IP
12	-	address and port are mapped to the same external IP address and port.
13	-	Unlike a full cone NAT, an external host (with IP address X) can send a
14	-	packet to the internal host only if the internal host had previously sent
15	-	a packet to IP address X.
16	-
17	-	* Port Restricted Cone NAT
18	-	A port restricted cone NAT is like a restricted cone NAT, but the restriction
19	-	includes port numbers. Specifically, an external host can send a packet, with
20	-	source IP address X and source port P, to the internal host only if the internal
21	-	host had previously sent a packet to IP address X and port P.
22	-
23	-	* Symmetric NAT
24	-	A symmetric NAT is one where all requests from the same internal IP address
25	-	and port, to a specific destination IP address and port, are mapped to the
26	-	same external IP address and port. If the same host sends a packet with the
27	-	same source address and port, but to a different destination, a different mapping
28	-	is used. Furthermore, only the external host that receives a packet can send a
29	-	UDP packet back to the internal host.
30	-	*/
31	-	package nat
32	-

■ ■ ■ ■ ■ ■

component/nat/table.go

1	-	package nat
2	-
3	-	import (
4	-	"net"
5	-	"sync"
6	-	)
7	-
8	-	type Table struct {
9	-	mapping sync.Map
10	-	}
11	-
12	-	func (t *Table) Set(key string, pc net.PacketConn) {
13	-	t.mapping.Store(key, pc)
14	-	}
15	-
16	-	func (t *Table) Get(key string) net.PacketConn {
17	-	item, exist := t.mapping.Load(key)
18	-	if !exist {
19	-	return nil
20	-	}
21	-	return item.(net.PacketConn)
22	-	}
23	-
24	-	func (t Table) GetOrCreateLock(key string) (sync.Cond, bool) {
25	-	item, loaded := t.mapping.LoadOrStore(key, sync.NewCond(&sync.Mutex{}))
26	-	return item.(*sync.Cond), loaded
27	-	}
28	-
29	-	func (t *Table) Delete(key string) {
30	-	t.mapping.Delete(key)
31	-	}
32	-
33	-	func NewTable() *Table {
34	-	return &Table{}
35	-	}
36	-

Refactor: remove nat pkg