ipv6 - 重定向 ip6tables 中的端口

Question

如何使用 ip6tables 将一个端口重定向到另一个本地端口？例如像这样：ip6tables -t nat -A PREROUTING -j REDIRECT -p tcp --dport 443 --to-ports 8443

Answer 1

嗯，这是一个老问题，但因为我需要做同样的事情......这是我发现的：

TPROXY

This target is only valid in the mangle table, in the PREROUTING chain and user-defined chains which are only called from this chain. It redirects the packet to a local socket without changing the packet header in any way. It can also change the mark value which can then be used in advanced routing rules. It takes three options:
--on-port port
    This specifies a destination port to use. It is a required option, 0 means the new destination port is the same as the original. This is only valid if the rule also specifies -p tcp or -p udp. 
--on-ip address
    This specifies a destination address to use. By default the address is the IP address of the incoming interface. This is only valid if the rule also specifies -p tcp or -p udp. 
--tproxy-mark value[/mask]
    Marks packets with the given value/mask. The fwmark value set here can be used by advanced routing. (Required for transparent proxying to work: otherwise these packets will get forwarded, which is probably not what you want.)

当然，这仅对 ip6tables 有效。所以我想这是有效的：

ip6tables -t mangle -A PREROUTING -p tcp --dport 443 -j TPROXY --on-port 8443

但是，我还没有尝试过。

Answer 2

ip6tables不支持REDIRECT。（通常人们在 NAT 环境中使用它，而 IPv6 通常不支持 NAT。）

如果您只需以普通用户身份绑定到低端口，为什么不尝试此答案中描述的解决方法？当然，就 Tomcat 而言，这听起来意味着赋予任何 Java 进程该能力。