feature request: inbound interface binding

[Zerorigin]

打算将 realm 部署在网关路由器上，网关上的虚拟接口 lan（br-lan）绑定了多个网口设备 ethX，并通过 vlan 划分了多个虚拟子接口，我想在其中一个虚拟子接口监听特定端口进行转发，但 realm 似乎还是会监听所有的 IPv4、IPv6 地址，而不是仅监听虚拟子接口 interface 上的 IPv4、IPv6 地址。

我的配置如下：

[log]
level = "warn"

[network]
no_tcp = false
use_udp = false

# DeepLX - API
[[endpoints]]
listen = "[::]:1188"
remote = "1.2.3.4:1188"
interface = "vlan_Services"

[zephyrchien]

@Zerorigin Thanks for the detailed description which is really helpful to understand your use case and locate the problem.

Currently the interface argument is just for outbound connections/traffics. Inbound ones has not been implemented but I will add this missing feature soon when I have time.

[zephyrchien]

@Zerorigin Hey, maybe you could use specific ip address instead of [::]

[Zerorigin]

@Zerorigin Hey, maybe you could use specific ip address instead of [::]

不太可行，因为 IPv6 地址不是固定的。

[zephyrchien]

Okay. Technically I think it's feasible to bind a LISTEN socket to a given interface with setsockopt(SO_BINDTODEVICE), which would be helpful to your use case.

[zephyrchien]

Hey @Zerorigin ,

Now you could specify the inbound interface by adding -e <iface> to cmd arguments; or with a config file (docs here):

[[endpoint]]
#...
listen_interface = "<iface>"

[Zerorigin]

Hey @Zerorigin ,

Now you could specify the inbound interface by adding -e <iface> to cmd arguments; or with a config file (docs here):

[[endpoint]]
#...
listen_interface = "<iface>"

大佬，有点强，setsockopt(SO_BINDTODEVICE)相关资料其实之前我也搜过，但是感觉自己估计搞不定，就没尝试编写代码测试。 我这两天抽空测试下新的配置项，到时候再来找您反馈。

[Zerorigin]

Now you could specify the inbound interface by adding -e <iface> to cmd arguments; or with a config file (docs here):

[[endpoint]]
#...
listen_interface = "<iface>"

在基于 Linux 内核的路由网关平台上测试了下， 能在子接口的 IPv4 & IPv6 入站正确监听相关端口并转发了， 并且网关宽带重新拨号后，也能在子接口新分配的 IP 上监听， 感觉没啥问题了，这个 issue 应该可以考虑关闭了。