feat: initial commit

cmd/agent/main.go

@@ -0,0 +1,64 @@
+// Command agent is the Linux client installed on machines without a public IP.
+// It runs as a root systemd service, dials the server over HTTP long-polling,
+// and opens a root PTY when an admin requests a terminal in the web panel.
+package main
+
+import (
+	"context"
+	"log"
+	"net"
+	"net/url"
+	"os"
+	"os/signal"
+	"syscall"
+
+	"github.com/x-grk/longpolling-remote-access/internal/agent"
+)
+
+func main() {
+	host := envOr("HOST", "https://REDACTED:8445")
+	cfg := agent.Config{
+		Host:         host,
+		EnrollSecret: os.Getenv("ENROLL_SECRET"),
+		Name:         os.Getenv("AGENT_NAME"),
+		StatePath:    envOr("STATE_PATH", "/etc/lpagent/state.json"),
+		TunnelAddr:   tunnelAddr(host),
+	}
+	if cfg.EnrollSecret == "" {
+		// Only required for the very first run (before enrollment).
+		if _, err := os.Stat(cfg.StatePath); os.IsNotExist(err) {
+			log.Fatal("ENROLL_SECRET is required for first enrollment")
+		}
+	}
+
+	ctx, stop := signal.NotifyContext(context.Background(), syscall.SIGINT, syscall.SIGTERM)
+	defer stop()
+
+	if err := agent.New(cfg).Run(ctx); err != nil {
+		log.Fatalf("agent: %v", err)
+	}
+}
+
+func envOr(key, def string) string {
+	if v := os.Getenv(key); v != "" {
+		return v
+	}
+	return def
+}
+
+// tunnelAddr derives the direct-tunnel address (host:8446) from the server URL.
+// TUNNEL_ADDR overrides it entirely; TUNNEL_PORT overrides just the port.
+// Set TUNNEL_ADDR=off to disable the direct tunnel.
+func tunnelAddr(hostURL string) string {
+	if v := os.Getenv("TUNNEL_ADDR"); v != "" {
+		if v == "off" {
+			return ""
+		}
+		return v
+	}
+	u, err := url.Parse(hostURL)
+	if err != nil || u.Hostname() == "" {
+		return ""
+	}
+	return net.JoinHostPort(u.Hostname(), envOr("TUNNEL_PORT", "8446"))
+}