[Help/Question] How can we make client as a proxy in reverse proxy tunnel ?

[xzycn]

As the docs(https://gost.run/tutorials/reverse-proxy-tunnel/) say, the test config as follows:
client side :

log:
  level: debug
services:
  - name: service-0
    addr: :0
    handler:
      type: rtcp
    listener:
      type: rtcp
      chain: chain-0

chains:
  - name: chain-0
    hops:
      - name: hop-0
        nodes:
          - name: node-0
            addr: [server_ip]:8443
            connector:
              type: tunnel
              metadata:
                tunnel.id: 4d21094e-b74c-4916-86c1-d9fa36ea677b
                tunnel.weight: 1
            dialer:
              type: tcp

server side :

services:
  - name: service-0
    addr: :8443
    handler:
      type: tunnel
      metadata:
        entrypoint: "127.0.0.1:10086"
        ingress: ingress-0
    listener:
      type: tcp

ingresses:
  - name: ingress-0
    rules:
      - hostname: "example.com"
        endpoint: 4d21094e-b74c-4916-86c1-d9fa36ea677b

Well, after starting them in each node, we can visit http://ipinfo.io by curl -x server_ip:10086 http://example.com, but https failed with TLS shakehand error. After some investigations, found that entrypoint hanler don't handle connect method expect one case:

if v[0] == relay.Version1 {
		return ep.handleConnect(ctx, xnet.NewBufferReaderConn(conn, br), log)
}

some questions:
1 What should we do to make the request from curl as a relay request?
2 Now the entrypoint handler only support HTTP proxy request, could we create a auto type handler(support socks and http) forward the request to entrypoint handler?

In one word, how can we access any websites or applications(TCP or UDP) from server side? Thx.

[ginuerzh]

The entrypoint in tunnel handler is a normal HTTP reverse proxy service (not an HTTP proxy), used as a convenient way to access web services, and only accepts normal HTTP requests. For non-HTTP traffic, a separate TCP (or UDP) entrypoint needs to be run.

services:
  - name: entrypoint
    addr: :8000
    handler:
      type: tcp
      chain: chain-0
    listener:
      type: tcp
    forwarder:
      nodes:
        - name: target-0
          addr: example.com
chains:
  - name: chain-0
    hops:
      - name: hop-0
        nodes:
          - name: node-0
            addr: :8443
            connector:
              type: tunnel
              metadata:
                tunnel.id: 4d21094e-b74c-4916-86c1-d9fa36ea677b
            dialer:
              type: tcp

See https://gost.run/tutorials/reverse-proxy-tunnel/#tcp

[xzycn]

@ginuerzh
We don't know which website will be visited in advance, we need make client (or whole thing including server 、client and tunnel bettwen them) as a proxy, we should provide a proxy to our mates instead of a reverse proxy.Is there a suitable way for our use case ?

[ginuerzh]

Do you want to expose the internal proxy service and access other services through the proxy? As mentioned above, you need to run a TCP entrypoint and map it to the internal proxy server.

For example

Client side

Proxy server that need to be exposed

gost -L :8080

Tunnel client

gost -L rtcp://:0/:8080 -F tunnel://[server_ip]:8443?tunnel.id=4d21094e-b74c-4916-86c1-d9fa36ea677b

services:
  - name: service-0
    addr: :0
    handler:
      type: rtcp
    listener:
      type: rtcp
      chain: chain-0
   forwarder:
      nodes:
        - name: target-0
          addr: :8080
chains:
  - name: chain-0
    hops:
      - name: hop-0
        nodes:
          - name: node-0
            addr: [server_ip]:8443
            connector:
              type: tunnel
              metadata:
                tunnel.id: 4d21094e-b74c-4916-86c1-d9fa36ea677b
            dialer:
              type: tcp

Server side

Tunnel service

gost -L tunnel://:8443?tunnel=proxy:4d21094e-b74c-4916-86c1-d9fa36ea677b

services:
  - name: service-0
    addr: :8443
    handler:
      type: tunnel
      metadata:
        ingress: ingress-0
    listener:
      type: tcp

ingresses:
  - name: ingress-0
    rules:
      - hostname: "proxy"
        endpoint: 4d21094e-b74c-4916-86c1-d9fa36ea677b

TCP entrypoint

gost -L tcp://:8000/proxy -F tunnel://:8443?tunnel.id=4d21094e-b74c-4916-86c1-d9fa36ea677b

services:
  - name: entrypoint
    addr: :8000
    handler:
      type: tcp
      chain: chain-0
    listener:
      type: tcp
    forwarder:
      nodes:
        - name: target-0
          addr: proxy
chains:
  - name: chain-0
    hops:
      - name: hop-0
        nodes:
          - name: node-0
            addr: :8443
            connector:
              type: tunnel
              metadata:
                tunnel.id: 4d21094e-b74c-4916-86c1-d9fa36ea677b
            dialer:
              type: tcp

NOTE: the hostname in the ingress rule is a virtual host, it is used for tunnel routing.

Then you can use the entrypoint as a proxy to access other services:

curl --socks5-hostname server_ip:8000 https://ipinfo.io

[xzycn]

@ginuerzh
It works, the configs are a bit complicated, we even thought metadata.entrypoint is required for tunnel handler,no idea it can be a seperated service, and there is no docs for tunnel handler and tunnel connector now in https://gost.run.
IMHO,if it means we need to create a TCP entrypoint to a tunnel(ie. a new forwarder node, a new chain, and a newingress rule) ? If so, it will be a problem when we have a lot tunnel clients, right?