pubkey_svc

README

pubkey_svc

pubkey_svc fork 自 wgsd, 裁剪了部分功能, 作为 CoreDNS 的插件使用. 原项目提供了一个绝妙的点子: 把公钥当作 URL. 在 DNS 服务的基础上稍加改动就能实现两端 NAT 后主机打洞.

build

git clone https://github.com/coredns/coredns.git && cd coredns
echo "pubkey_svc:github.com/punksnail/pubkey_svc" >> plugin.cfg
go generate && go build

./coredns -plugins | grep pubkey_svc # 若成功作为插件编译则输出 "dns.pubkey_svc"

# 编译 CoreDNS 后, 配置文件 Corefile 就可以添加如下配置
.:<port> {
    pubkey_svc <zone> <wg device>
}

echo -e ".:5300 {\n\tdebug\n\tpubkey_svc snail tunnel\n}" > Corefile # 为 pubkey_svc 传入分区与设备名称

usage

这里的用途是 NAT hole punching, 很难简单描述, 具体参考 WireGuard Endpoint Discovery and NAT Traversal

Hole Punching 通信流程:

   Alice                    Punching Server                        Bob
(behind NAT)                    (global IP)                   (behind NAT)
    |                               |                               |
    |       wireguard handshake     |       wireguard handshake     |
    +------------------------------>|<------------------------------+
    |       establish tunnel        |       establish tunnel        |
    |<----------------------------->|<----------------------------->|
    |                               |                               |
    |       The server has recorded the IP:port of both peers       |
    |                               |                               |
    |                               |                               |
    |   query with Bob's public key |                               |
    +------------------------------>|                               |
    |                            wg show                            |
    |   answer Bob's IP:port    matching Bob                        |
    |<------------------------------+                               |
    |                               |                               |
 set tunnel peer                    |                               |
    |                       wireguard handshake                     |
    +-------------------------------------------------------------->|
    |                       establish tunnel                        |
    |<------------------------------------------------------------->|
    |                                                               |

补充:
    1. 在通信开始前各方都已知彼此的公钥, 以此为基础才能建立隧道
    2. Alice 与 Bob 在一开始不知道彼此的 IP:port, 但预设了隧道配置

例:
nohup ./coredns &   # Punching Server 后台运行 DNS 服务

# Alice 编译 pubkey_dns_client 后, 通过 Bob's public key 配置隧道
./pubkey_dns_client -device=<device name> -dns=<server ip>:<port> -zone=snail -pubkey <Bob's public key>

Documentation

Index

• type PubKeySvc
  • func (svc *PubKeySvc) Name() string
  • func (svc *PubKeySvc) ServeDNS(ctx context.Context, w dns.ResponseWriter, msg *dns.Msg) (int, error)
• type Zone
• type Zones

Types

type PubKeySvc

type PubKeySvc struct {
	Next plugin.Handler
	Zones
	// contains filtered or unexported fields
}

PubKeySvc is a CoreDNS plugin that provides WireGuard peer information * via DNS-SD semantics. * * PubKeySvc implements the plugin.Handler interface.

func (*PubKeySvc) Name

func (svc *PubKeySvc) Name() string

func (*PubKeySvc) ServeDNS

func (svc *PubKeySvc) ServeDNS(ctx context.Context,
	w dns.ResponseWriter, msg *dns.Msg) (int, error)

type Zone

type Zone struct {
	// contains filtered or unexported fields
}

type Zones

type Zones struct {
	// contains filtered or unexported fields
}