+----+-----+-------+------+----------+----------+
|VER | REP | RSV | ATYP | BND.ADDR | BND.PORT |
+----+-----+-------+------+----------+----------+
| 1 | 1 | X'00' | 1 | Variable | 2 |
+----+-----+-------+------+----------+----------+
Where:
o VER protocol version: X'05' ------------ 固定 05
o REP Reply field:
o X'00' succeeded ------------ 若为 00 成功 其余可以都看成失败
o X'01' general SOCKS server failure
o X'02' connection not allowed by ruleset
o X'03' Network unreachable
o X'04' Host unreachable
o X'05' Connection refused
o X'06' TTL expired
o X'07' Command not supported
o X'08' Address type not supported
o X'09' to X'FF' unassigned
o RSV RESERVED
o ATYP address type of following address
o IP V4 address: X'01'
o DOMAINNAME: X'03'
o IP V6 address: X'04'
o BND.ADDR server bound address
o BND.PORT server bound port in network octet order
Fields marked RESERVED (RSV) must be set to X'00'.
可见,对于返回信息,只须判断第二字节是否为00.若为 00 连接成功,剩下的操作和直连一样,Winsock可直接用SendData 和 GetData 发送\接受数据.
下面介绍需要验证用户名/密码的socks5穿透
第一步还是发送三个字节,只是内容有变,展开来写为: 05 01 02
服务器返回信息也有所不同,正确的返回为 05 02
成功后发送用户/密码信息,请看RFC 说明: