Make SSH timeout adjustable, document more container options

commit-id:55297dc4

README.md

@@ -178,6 +178,24 @@ See [here](https://josh-project.github.io/josh/faq.html)
             Default: 8022
         </td>
     </tr>
+    <tr>
+        <td>
+            <code>JOSH_SSH_MAX_STARTUPS</code>
+        </td>
+        <td>
+            Maximum number of concurrent SSH authentication attempts. Default: 16
+        </td>
+    </tr>
+    <tr>
+        <td>
+            <code>JOSH_SSH_TIMEOUT</code>
+        </td>
+        <td>
+            Timeout, in seconds, for a single request when serving repos over SSH.
+            This time should cover fetch from upstream repo, filtering, and serving
+            repo to client. Default: 300
+        </td>
+    </tr>
     <tr>
         <td>
             <code>JOSH_EXTRA_OPTS</code>

docker/etc/ssh/sshd_config.template

@@ -21,11 +21,12 @@ X11Forwarding no
 PrintMotd no
 
 # Accepted environment variables
+
 AcceptEnv GIT_PROTOCOL
 
 # fail2ban-like features
 
-PerSourceMaxStartups 10
+PerSourceMaxStartups ${JOSH_SSH_MAX_STARTUPS}
 PerSourceNetBlockSize 32:128
 
 # Client management

docker/s6-rc.d/sshd-generate-config/up

@@ -1,8 +1,10 @@
 #!/command/execlineb -P
 
 importas -D 8022 josh_ssh_port JOSH_SSH_PORT
+importas -D 16 josh_ssh_max_startups JOSH_SSH_MAX_STARTUPS
 emptyenv -p
 backtick JOSH_SSH_PORT { echo ${josh_ssh_port} }
+backtick JOSH_SSH_MAX_STARTUPS { echo ${josh_ssh_max_startups} }
 foreground
 {
   redirfd -r 0 /etc/ssh/sshd_config.template

docker/s6-rc.d/sshd/run

@@ -1,3 +1,11 @@
 #!/command/execlineb -P
 
-/usr/sbin/sshd -e -D -h /data/keys/.ssh/id_ed25519
+importas josh_http_port JOSH_HTTP_PORT
+importas josh_ssh_timeout JOSH_SSH_TIMEOUT
+
+/usr/sbin/sshd \
+  -e \
+  -D \
+  -h/data/keys/.ssh/id_ed25519 \
+  -oSetEnv=JOSH_SSH_SHELL_TIMEOUT=${josh_ssh_timeout} \
+  -oSetEnv=JOSH_SSH_SHELL_ENDPOINT_PORT=${josh_http_port}

josh-ssh-shell/src/bin/josh-ssh-shell.rs

@@ -26,8 +26,8 @@ struct Args {
     command: String,
 }
 
-const HTTP_REQUEST_TIMEOUT: u64 = 120;
-const HTTP_JOSH_SERVER_PORT: &str = "8000";
+const HTTP_REQUEST_TIMEOUT: u64 = 300;
+const HTTP_JOSH_SERVER_PORT: u16 = 8000;
 
 fn die(message: &str) -> ! {
     eprintln!("josh-ssh-shell: {}", message);
@@ -59,12 +59,30 @@ impl Display for CallError {
     }
 }
 
+fn get_env_int<T: std::str::FromStr>(env_var: &str, default: T) -> T
+where
+    <T as std::str::FromStr>::Err: Display,
+{
+    let message = format!(
+        "Invalid {} value of env var {}",
+        std::any::type_name::<T>(),
+        env_var
+    );
+
+    env::var(env_var)
+        .map(|v| v.parse::<T>().unwrap_or_else(|_| die(&message)))
+        .unwrap_or(default)
+}
+
 fn get_endpoint() -> String {
-    let port =
-        std::env::var("JOSH_SSH_SHELL_ENDPOINT_PORT").unwrap_or(HTTP_JOSH_SERVER_PORT.to_string());
+    let port = get_env_int("JOSH_SSH_SHELL_ENDPOINT_PORT", HTTP_JOSH_SERVER_PORT);
     format!("http://localhost:{}", port)
 }
 
+fn get_timeout() -> u64 {
+    get_env_int("JOSH_SSH_SHELL_TIMEOUT", HTTP_REQUEST_TIMEOUT)
+}
+
 async fn handle_command(
     command: RequestedCommand,
     ssh_socket: &Path,
@@ -151,7 +169,7 @@ async fn handle_command(
             .post(format!("{}/serve_namespace", get_endpoint()))
             .header(CONTENT_TYPE, "application/json")
             .body(serde_json::to_string(&rpc_payload).unwrap())
-            .timeout(Duration::from_secs(HTTP_REQUEST_TIMEOUT))
+            .timeout(Duration::from_secs(get_timeout()))
             .send()
             .await?;