feat(cli,server): add configurable control port

README.md

@@ -18,12 +18,12 @@ This produces an executable named `spore` in the project directory.
 ## Quickstart
 ### Server (choose a public range)
 ```bash
-./spore server --min-port 20000 --max-port 21000 --bind-addr 0.0.0.0
+./spore server --min-port 20000 --max-port 21000 --bind-addr 0.0.0.0 [--control-port 7835]
 ```
 
 ### Client (forward local 3000; let server assign a port)
 ```bash
-./spore local --local-host 127.0.0.1 --local-port 3000 --to <SERVER_HOST> --port 0
+./spore local --local-host 127.0.0.1 --local-port 3000 --to <SERVER_HOST> --port 0 [--control-port 7835]
 ```
 Spore prints the assigned public port (for example, `listening at <SERVER_HOST>:20345`).
 
@@ -34,11 +34,11 @@ python3 -m http.server 25565
 ```
 Terminal B (server):
 ```bash
-./spore server --min-port 20000 --max-port 21000 --bind-addr 127.0.0.1
+./spore server --min-port 20000 --max-port 21000 --bind-addr 127.0.0.1 [--control-port 7835]
 ```
 Terminal C (client):
 ```bash
-./spore local --local-host 127.0.0.1 --local-port 25565 --to 127.0.0.1 --port 0
+./spore local --local-host 127.0.0.1 --local-port 25565 --to 127.0.0.1 --port 0 [--control-port 7835]
 ```
 Terminal D (access through tunnel):
 ```bash
@@ -48,8 +48,8 @@ curl -v 127.0.0.1:<ASSIGNED_PORT>/
 ## Authentication (optional)
 Provide the same secret on both sides to restrict access:
 ```bash
-./spore server --secret SECRET
-./spore local --local-port 3000 --to <SERVER_HOST> --secret SECRET
+./spore server --secret SECRET [--control-port 7835]
+./spore local --local-port 3000 --to <SERVER_HOST> --secret SECRET [--control-port 7835]
 ```
 
 ## Interoperability
@@ -60,9 +60,9 @@ Spore is designed to speak the same control protocol as Bore. You can mix Rust B
 - Pending inbound connections are stored for up to 10 seconds; if the client does not accept within that window, they are dropped.
 
 ## Troubleshooting
-- "address in use" starting server: another process is listening on TCP 7835. Stop it or choose a different control port (not yet configurable in Spore).
-- Client exits with `:eof`: ensure server is reachable at `--to`, secrets match (or are omitted on both), and TCP 7835 is open.
-- Repeated "removed stale connection": ensure the client is running and that a remote connection arrives soon after the client starts (Spore holds pending connections for 10s).
+- "address in use" starting server: another process is listening on the control port. Use `--control-port` to choose a different one or stop the existing process.
+- Client exits with `:eof`: ensure server is reachable at `--to`, secrets match (or are omitted on both), and the control port is open.
+- Repeated "removed stale connection": ensure the client is running and a remote connection arrives soon after the client starts (Spore holds pending connections for 10s).
 
 ## License
 MIT, following the upstream project.

config/config.exs

@@ -1,3 +1,12 @@
 import Config
 
 config :logger, level: :info
+
+# Allow overriding the control port via env var SPORE_CONTROL_PORT
+spore_control_port =
+  case System.get_env("SPORE_CONTROL_PORT") do
+    nil -> 7835
+    str -> String.to_integer(str)
+  end
+
+config :spore, control_port: spore_control_port

lib/spore/cli.ex

@@ -20,7 +20,8 @@ defmodule Spore.CLI do
           local_host: :string,
           to: :string,
           port: :integer,
-          secret: :string
+          secret: :string,
+          control_port: :integer
         ],
         aliases: [p: :port]
       )
@@ -30,6 +31,9 @@ defmodule Spore.CLI do
     to = Keyword.fetch!(opts, :to)
     port = Keyword.get(opts, :port, 0)
     secret = Keyword.get(opts, :secret, nil)
+    control_port = Keyword.get(opts, :control_port, nil)
+
+    if control_port, do: Application.put_env(:spore, :control_port, control_port)
 
     case Spore.Client.new(local_host, local_port, to, port, secret) do
       {:ok, client} ->
@@ -51,7 +55,8 @@ defmodule Spore.CLI do
           max_port: :integer,
           secret: :string,
           bind_addr: :string,
-          bind_tunnels: :string
+          bind_tunnels: :string,
+          control_port: :integer
         ]
       )
 
@@ -60,6 +65,9 @@ defmodule Spore.CLI do
     secret = Keyword.get(opts, :secret, nil)
     bind_addr = Keyword.get(opts, :bind_addr, "0.0.0.0")
     bind_tunnels = Keyword.get(opts, :bind_tunnels, nil)
+    control_port = Keyword.get(opts, :control_port, nil)
+
+    if control_port, do: Application.put_env(:spore, :control_port, control_port)
 
     case Spore.Server.listen(
            min_port: min_port,
@@ -76,8 +84,8 @@ defmodule Spore.CLI do
   defp usage(io) do
     IO.puts(io, """
     Usage:
-      spore local --local-port <PORT> --to <HOST> [--local-host HOST] [--port PORT] [--secret SECRET]
-      spore server [--min-port N] [--max-port N] [--secret SECRET] [--bind-addr IP] [--bind-tunnels IP]
+      spore local --local-port <PORT> --to <HOST> [--local-host HOST] [--port PORT] [--secret SECRET] [--control-port N]
+      spore server [--min-port N] [--max-port N] [--secret SECRET] [--bind-addr IP] [--bind-tunnels IP] [--control-port N]
     """)
   end
 end

lib/spore/shared.ex

@@ -10,8 +10,10 @@ defmodule Spore.Shared do
   @max_frame_length 256
   @network_timeout_ms 3_000
 
-  @doc "TCP port used for control connections with the server."
-  def control_port, do: @control_port
+  @doc "TCP port used for control connections with the server. Can be overridden via Application env :spore, :control_port."
+  def control_port do
+    Application.get_env(:spore, :control_port, @control_port)
+  end
 
   @doc "Default timeout for initial network operations (ms)."
   def network_timeout_ms, do: @network_timeout_ms