docs(step1): add wireguard server/client scripts + reset guide

doc/step-001-wireguard-tools.md

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+# Step 001A: WireGuard tools (server/client) + instrukcje reset
+
+Ten step dodaje dwa skrypty pomocnicze do zarzadzania WireGuard:
+
+- server: `scripts/wireguard/wg_serverctl.py`
+- client: `scripts/wireguard/wg_client.py`
+
+Skrypty trzymaja stan na dysku, zgodnie z konwencja:
+
+- server keys: `/etc/wireguard/server.key`, `/etc/wireguard/server.pub`
+- clients: `/etc/wireguard/clients/<name>.key|.pub|.ip|.conf`
+- generated server config: `/etc/wireguard/wg0.conf`
+
+Wymagania: `wireguard-tools` (czyli `wg`, `wg-quick`) + `systemd`.
+
+## Instalacja (server)
+
+Na bare metalu:
+
+```bash
+apt-get update
+apt-get install -y wireguard
+```
+
+Z repo (na hoście) zainstaluj skrypt jako root-only:
+
+```bash
+install -m 700 scripts/wireguard/wg_serverctl.py /usr/local/sbin/wg_serverctl.py
+```
+
+## Instalacja (client)
+
+Na kliencie (laptop/VPS):
+
+```bash
+apt-get update
+apt-get install -y wireguard
+install -m 700 scripts/wireguard/wg_client.py /usr/local/sbin/wg_client.py
+```
+
+## Typowy flow (server)
+
+```bash
+# 1) wygeneruj klucze serwera
+wg_serverctl.py gen-server --force
+
+# 2) wygeneruj klucze klienta (trzymane na serwerze w /etc/wireguard/clients)
+wg_serverctl.py gen-client client1
+
+# 3) dodaj klienta do puli, wygeneruj wg0.conf i zrestartuj wg-quick@wg0
+wg_serverctl.py add client1
+
+# 4) wyeksportuj client config (do przekazania na klienta)
+wg_serverctl.py export client1
+
+# 5) podglad
+wg_serverctl.py list
+wg_serverctl.py show client1
+```
+
+Plik konfiguracyjny klienta powstaje jako:
+
+- `/etc/wireguard/clients/client1.conf`
+
+## Typowy flow (client)
+
+Skopiuj `client1.conf` na klienta, a potem:
+
+```bash
+wg_client.py install ./client1.conf
+wg_client.py up
+wg_client.py status
+```
+
+## Stop / disable / reset wg0 (Ubuntu 24.04)
+
+Stop (zostaw config, tylko down):
+
+```bash
+systemctl stop wg-quick@wg0
+```
+
+Disable autostart:
+
+```bash
+systemctl disable wg-quick@wg0
+```
+
+Flush (pewny down + usuniecie interfejsu):
+
+```bash
+systemctl stop wg-quick@wg0
+ip link del wg0 2>/dev/null || true
+ip a show wg0 2>/dev/null || echo "wg0 not present"
+```
+
+Hard reset (usuniecie kluczy + konfiguracji):
+
+```bash
+systemctl stop wg-quick@wg0
+systemctl disable wg-quick@wg0
+ip link del wg0 2>/dev/null || true
+
+rm -f /etc/wireguard/wg0.conf
+rm -f /etc/wireguard/server.key /etc/wireguard/server.pub
+rm -rf /etc/wireguard/clients
+```
+
+Reset peerow bez kasowania server key:
+
+```bash
+systemctl stop wg-quick@wg0
+rm -f /etc/wireguard/clients/*.pub /etc/wireguard/clients/*.ip
+systemctl start wg-quick@wg0
+```
+

doc/step-001-wireguard-ufw-ssh-only.md

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+# Step 001: WireGuard + UFW + SSH tylko po WG (Ubuntu 24.04, 1 NIC)
+
+Cel: na świeżym Ubuntu 24.04 na bare metalu ustawić:
+
+- **WireGuard** jako prywatny kanał administracyjny,
+- **SSH dostępne tylko przez WireGuard**,
+- przygotować grunt pod **Agave RPC dostępne tylko przez WireGuard** (8899/8900 prywatnie),
+- zostawić porty klastra Agave na publicznym NIC, żeby node mógł się zsynchronizować.
+
+Kolejność jest krytyczna: najpierw uruchom WireGuard i sprawdź, że działa, dopiero potem ograniczaj SSH/firewall.
+
+## Założenia
+
+- Host ma **1 publiczny interfejs** (np. `enp1s0`).
+- WireGuard interfejs to `wg0`.
+- Masz dostęp awaryjny do konsoli (IPMI/KVM) na wypadek pomyłki.
+
+## Parametry (dostosuj)
+
+```bash
+export PUBLIC_IFACE="enp1s0"
+export WG_IFACE="wg0"
+
+export WG_SERVER_IP="10.66.66.1/24"
+export WG_SERVER_IP_ONLY="10.66.66.1"
+export WG_PORT="51820"
+
+export WG_CLIENT_IP="10.66.66.2/32"
+export WG_CLIENT_PUBKEY="<PASTE_CLIENT_PUBLIC_KEY>"
+
+# Agave/validator ports
+export RPC_PORT="8899"
+export WS_PORT="8900"
+export DYNAMIC_PORT_RANGE="8000:8020"
+```
+
+## 1) WireGuard (nie ruszaj jeszcze SSH)
+
+### Instalacja
+
+```bash
+apt-get update
+apt-get install -y wireguard
+```
+
+### Klucze serwera
+
+```bash
+umask 077
+wg genkey | tee /etc/wireguard/server.key >/dev/null
+cat /etc/wireguard/server.key | wg pubkey | tee /etc/wireguard/server.pub >/dev/null
+cat /etc/wireguard/server.pub
+```
+
+### Konfiguracja `/etc/wireguard/wg0.conf`
+
+```bash
+cat >/etc/wireguard/${WG_IFACE}.conf <<EOF
+[Interface]
+Address = ${WG_SERVER_IP}
+ListenPort = ${WG_PORT}
+PrivateKey = $(cat /etc/wireguard/server.key)
+
+[Peer]
+PublicKey = ${WG_CLIENT_PUBKEY}
+AllowedIPs = ${WG_CLIENT_IP}
+EOF
+```
+
+Start:
+
+```bash
+systemctl enable --now wg-quick@${WG_IFACE}
+wg show
+ip a show ${WG_IFACE}
+```
+
+Test z klienta (po zestawieniu tunelu): `ping 10.66.66.1`.
+
+## 2) UFW: public tylko WG + porty klastra; prywatnie RPC/SSH po wg0
+
+Instalacja:
+
+```bash
+apt-get install -y ufw
+```
+
+Public: pozwól na WireGuard:
+
+```bash
+ufw allow ${WG_PORT}/udp
+```
+
+Public: pozwól na porty klastra Agave (żeby node mógł syncować).
+
+Uwaga: Solana/Agave używa głównie **UDP** w tym zakresie; jeśli będziesz miał problemy z reachability, rozważ dopuszczenie też TCP w tym samym zakresie.
+
+```bash
+ufw allow in on "${PUBLIC_IFACE}" to any port ${DYNAMIC_PORT_RANGE}/udp
+```
+
+Prywatnie (wg0): RPC/WS:
+
+```bash
+ufw allow in on "${WG_IFACE}" to any port ${RPC_PORT} proto tcp
+ufw allow in on "${WG_IFACE}" to any port ${WS_PORT} proto tcp
+```
+
+Na tym etapie NIE blokuj jeszcze publicznego SSH (żeby się nie zablokować).
+
+Włącz UFW:
+
+```bash
+ufw enable
+ufw status verbose
+```
+
+## 3) SSH tylko po WireGuard (dopiero gdy WG działa)
+
+### 3.1) UFW: pozwól na SSH po wg0
+
+```bash
+ufw allow in on "${WG_IFACE}" to any port 22 proto tcp
+```
+
+### 3.2) sshd: nasłuch tylko na WG IP
+
+Edytuj `sshd_config`:
+
+```bash
+sed -n '1,220p' /etc/ssh/sshd_config
+```
+
+Dodaj (lub ustaw) na końcu pliku:
+
+```conf
+PasswordAuthentication no
+PermitRootLogin no
+ListenAddress 10.66.66.1
+```
+
+Zanim zrestartujesz SSH:
+
+- miej otwartą obecną sesję SSH,
+- zestaw WG na kliencie,
+- przygotuj drugi terminal do testu po `10.66.66.1`.
+
+Restart:
+
+```bash
+systemctl restart ssh
+ss -lntp | grep -E ':22\\b' || true
+```
+
+Test z klienta po WG:
+
+```bash
+ssh <user>@10.66.66.1
+```
+
+Jeśli działa: zablokuj publiczny SSH:
+
+```bash
+ufw deny 22/tcp
+ufw status verbose
+```
+
+## 4) Kernel/sysctl baseline pod Agave (na tym etapie bez uruchamiania Agave)
+
+Minimalne wartości, które już mamy w Ansible (i kilka dodatkowych bezpiecznych):
+
+```bash
+cat >/etc/sysctl.d/90-agave.conf <<'EOF'
+fs.file-max = 2000000
+vm.max_map_count = 1000000
+net.core.somaxconn = 65535
+net.core.netdev_max_backlog = 250000
+net.core.rmem_max = 134217728
+net.core.wmem_max = 134217728
+EOF
+
+sysctl --system
+```
+
+Limity `nofile`:
+
+```bash
+cat >/etc/security/limits.d/90-solana.conf <<'EOF'
+* soft nofile 1000000
+* hard nofile 1000000
+EOF
+```
+
+## 5) Co dalej
+
+- Instalacja i uruchomienie Agave: patrz `doc/etap-007-manual-baremetal-rpc-commands.md`.
+- Narzedzia do generowania konfiguracji WireGuard (server/client) + reset wg0: patrz `doc/step-001-wireguard-tools.md`.
+- Docelowo: bind RPC/WS do WG IP (zamiast `0.0.0.0`) i spójne, minimalne reguły firewall.

scripts/wireguard/wg_client.py

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+#!/usr/bin/env python3
+import argparse
+import os
+import shutil
+import subprocess
+import sys
+from pathlib import Path
+from datetime import datetime
+
+WG_DIR = Path("/etc/wireguard")
+WG0 = WG_DIR / "wg0.conf"
+
+
+def require_root():
+    if os.geteuid() != 0:
+        print("ERROR: run as root (sudo).", file=sys.stderr)
+        sys.exit(1)
+
+
+def run(cmd, check=True, capture=False):
+    return subprocess.run(
+        cmd,
+        check=check,
+        text=True,
+        stdout=subprocess.PIPE if capture else None,
+        stderr=subprocess.PIPE if capture else None,
+    )
+
+
+def backup_if_exists(p: Path):
+    if p.exists():
+        ts = datetime.now().strftime("%Y-%m-%d_%H%M%S")
+        b = p.with_name(p.name + f".bak.{ts}")
+        shutil.copy2(p, b)
+
+
+def cmd_install(src: str):
+    srcp = Path(src)
+    if not srcp.exists():
+        raise RuntimeError(f"Missing source config: {srcp}")
+    WG_DIR.mkdir(parents=True, exist_ok=True)
+    os.chmod(WG_DIR, 0o700)
+    backup_if_exists(WG0)
+    shutil.copy2(srcp, WG0)
+    os.chmod(WG0, 0o600)
+    os.chown(WG0, 0, 0)
+    print(f"OK: installed {WG0}")
+
+
+def cmd_up():
+    run(["wg-quick", "up", "wg0"], check=True)
+
+
+def cmd_down():
+    run(["wg-quick", "down", "wg0"], check=False)
+
+
+def cmd_status():
+    run(["wg", "show"], check=False)
+    run(["ip", "a", "show", "wg0"], check=False)
+
+
+def main():
+    require_root()
+    p = argparse.ArgumentParser(prog="wg_client.py")
+    sub = p.add_subparsers(dest="cmd", required=True)
+
+    i = sub.add_parser("install")
+    i.add_argument("config", help="Path to clientX.conf from server export")
+
+    sub.add_parser("up")
+    sub.add_parser("down")
+    sub.add_parser("status")
+
+    args = p.parse_args()
+
+    try:
+        if args.cmd == "install":
+            cmd_install(args.config)
+        elif args.cmd == "up":
+            cmd_up()
+        elif args.cmd == "down":
+            cmd_down()
+        elif args.cmd == "status":
+            cmd_status()
+    except Exception as e:
+        print(f"ERROR: {e}", file=sys.stderr)
+        sys.exit(1)
+
+
+if __name__ == "__main__":
+    main()
+

scripts/wireguard/wg_serverctl.py

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+#!/usr/bin/env python3
+import argparse
+import os
+import re
+import shutil
+import subprocess
+import sys
+from dataclasses import dataclass
+from datetime import datetime
+from pathlib import Path
+from typing import Optional, List
+
+WG_KEY_RE = re.compile(r"^[A-Za-z0-9+/]{43}=$")
+
+
+@dataclass
+class Cfg:
+    wg_dir: Path = Path("/etc/wireguard")
+    clients_dir: Path = Path("/etc/wireguard/clients")
+    server_key: Path = Path("/etc/wireguard/server.key")
+    server_pub: Path = Path("/etc/wireguard/server.pub")
+    wg0_conf: Path = Path("/etc/wireguard/wg0.conf")
+
+    wg_addr: str = "10.66.66.1/24"
+    wg_port: int = 51820
+    keepalive: int = 25
+
+    client_net_prefix: str = "10.66.66."
+    client_ip_start: int = 2
+    client_ip_end: int = 254
+
+
+def require_root():
+    if os.geteuid() != 0:
+        print("ERROR: run as root (sudo).", file=sys.stderr)
+        sys.exit(1)
+
+
+def run(
+    cmd: List[str],
+    capture: bool = False,
+    check: bool = True,
+    input_text: Optional[str] = None,
+) -> subprocess.CompletedProcess:
+    return subprocess.run(
+        cmd,
+        text=True,
+        input=input_text,
+        stdout=subprocess.PIPE if capture else None,
+        stderr=subprocess.PIPE if capture else None,
+        check=check,
+    )
+
+
+def ensure_dirs(cfg: Cfg):
+    cfg.wg_dir.mkdir(parents=True, exist_ok=True)
+    cfg.clients_dir.mkdir(parents=True, exist_ok=True)
+    os.chmod(cfg.wg_dir, 0o700)
+    os.chmod(cfg.clients_dir, 0o700)
+
+
+def read_first_nonempty_line(p: Path) -> str:
+    if not p.exists():
+        return ""
+    for line in p.read_text(encoding="utf-8", errors="ignore").splitlines():
+        line = line.strip().replace("\r", "")
+        if line:
+            return line
+    return ""
+
+
+def validate_key(k: str, what: str):
+    if not WG_KEY_RE.match(k):
+        raise ValueError(f"{what} has invalid WireGuard key format: {k!r}")
+
+
+def chmod600_root(p: Path):
+    os.chmod(p, 0o600)
+    os.chown(p, 0, 0)
+
+
+def backup_if_exists(p: Path):
+    if p.exists():
+        ts = datetime.now().strftime("%Y-%m-%d_%H%M%S")
+        b = p.with_name(p.name + f".bak.{ts}")
+        shutil.copy2(p, b)
+
+
+def gen_priv_key_to(path: Path):
+    priv = run(["wg", "genkey"], capture=True).stdout.strip()
+    validate_key(priv, "generated private key")
+    path.write_text(priv + "\n", encoding="utf-8")
+    chmod600_root(path)
+
+
+def pubkey_from_priv(priv: str) -> str:
+    validate_key(priv, "private key")
+    pub = run(["wg", "pubkey"], capture=True, input_text=priv + "\n").stdout.strip()
+    validate_key(pub, "generated public key")
+    return pub
+
+
+def detect_public_ip() -> str:
+    # Works on Ubuntu/Debian in typical setups
+    out = run(
+        [
+            "bash",
+            "-lc",
+            "ip route get 1.1.1.1 | awk '{for (i=1;i<=NF;i++) if ($i==\"src\") {print $(i+1); exit}}'",
+        ],
+        capture=True,
+    ).stdout.strip()
+    if not out:
+        raise RuntimeError("Could not detect server public IP.")
+    return out
+
+
+def restart_wg(unit: str = "wg-quick@wg0"):
+    run(["systemctl", "restart", unit], capture=False, check=True)
+    # optional status (non-fatal)
+    try:
+        run(["systemctl", "--no-pager", "-l", "status", unit], capture=False, check=False)
+    except Exception:
+        pass
+
+
+def list_clients(cfg: Cfg) -> List[str]:
+    pubs = sorted(cfg.clients_dir.glob("*.pub"))
+    return [p.stem for p in pubs]
+
+
+def used_octets(cfg: Cfg) -> set:
+    s = set()
+    for f in cfg.clients_dir.glob("*.ip"):
+        v = read_first_nonempty_line(f)
+        if v.isdigit():
+            s.add(int(v))
+    return s
+
+
+def alloc_octet(cfg: Cfg) -> int:
+    used = used_octets(cfg)
+    for i in range(cfg.client_ip_start, cfg.client_ip_end + 1):
+        if i not in used:
+            return i
+    raise RuntimeError("No free IPs left in pool.")
+
+
+def gen_server(cfg: Cfg, force: bool):
+    ensure_dirs(cfg)
+    if not force and (cfg.server_key.exists() or cfg.server_pub.exists()):
+        raise RuntimeError("Server key already exists. Use --force to overwrite.")
+    gen_priv_key_to(cfg.server_key)
+    priv = read_first_nonempty_line(cfg.server_key)
+    pub = pubkey_from_priv(priv)
+    cfg.server_pub.write_text(pub + "\n", encoding="utf-8")
+    chmod600_root(cfg.server_pub)
+    print("OK: generated server keys:")
+    print(f" - {cfg.server_key} (PRIVATE)")
+    print(f" - {cfg.server_pub} (PUBLIC)")
+    print("Server public key:")
+    print(pub)
+
+
+def gen_client(cfg: Cfg, name: str, force: bool):
+    ensure_dirs(cfg)
+    keyf = cfg.clients_dir / f"{name}.key"
+    pubf = cfg.clients_dir / f"{name}.pub"
+    if not force and (keyf.exists() or pubf.exists()):
+        raise RuntimeError(f"Client {name} exists. Use --force to overwrite.")
+    gen_priv_key_to(keyf)
+    priv = read_first_nonempty_line(keyf)
+    pub = pubkey_from_priv(priv)
+    pubf.write_text(pub + "\n", encoding="utf-8")
+    chmod600_root(pubf)
+    print("OK: generated client keys:")
+    print(f" - {keyf} (PRIVATE)")
+    print(f" - {pubf} (PUBLIC)")
+    print("Client public key:")
+    print(pub)
+
+
+def generate_wg0_conf(cfg: Cfg):
+    ensure_dirs(cfg)
+    if not cfg.server_key.exists():
+        raise RuntimeError("Missing server.key. Run gen-server first.")
+    server_priv = read_first_nonempty_line(cfg.server_key)
+    validate_key(server_priv, "server private key")
+
+    backup_if_exists(cfg.wg0_conf)
+
+    lines: List[str] = []
+    lines += [
+        "[Interface]",
+        f"Address = {cfg.wg_addr}",
+        f"ListenPort = {cfg.wg_port}",
+        f"PrivateKey = {server_priv}",
+    ]
+
+    for name in sorted(list_clients(cfg)):
+        pubf = cfg.clients_dir / f"{name}.pub"
+        ipf = cfg.clients_dir / f"{name}.ip"
+        if not ipf.exists():
+            raise RuntimeError(f"Client {name} has no .ip file (run add {name}).")
+        pub = read_first_nonempty_line(pubf)
+        validate_key(pub, f"client {name} pubkey")
+        octet = read_first_nonempty_line(ipf)
+        if not octet.isdigit():
+            raise RuntimeError(f"Invalid ip octet in {ipf}: {octet!r}")
+        o = int(octet)
+        if o < 2 or o > 254:
+            raise RuntimeError(f"Invalid ip octet in {ipf}: {o}")
+        lines += [
+            "",
+            "[Peer]",
+            f"# {name}",
+            f"PublicKey = {pub}",
+            f"AllowedIPs = {cfg.client_net_prefix}{o}/32",
+            f"PersistentKeepalive = {cfg.keepalive}",
+        ]
+
+    cfg.wg0_conf.write_text("\n".join(lines) + "\n", encoding="utf-8")
+    chmod600_root(cfg.wg0_conf)
+    print(f"OK: generated {cfg.wg0_conf}")
+
+
+def add_client(cfg: Cfg, name: str, pubkey: Optional[str], ip: Optional[str], no_restart: bool):
+    ensure_dirs(cfg)
+    pubf = cfg.clients_dir / f"{name}.pub"
+    ipf = cfg.clients_dir / f"{name}.ip"
+
+    # resolve pubkey
+    if pubkey:
+        pubkey = pubkey.strip()
+        validate_key(pubkey, "provided client public key")
+        pubf.write_text(pubkey + "\n", encoding="utf-8")
+        chmod600_root(pubf)
+    else:
+        if not pubf.exists():
+            raise RuntimeError(f"Missing {pubf}. Run gen-client {name} or provide --pubkey.")
+        pubkey = read_first_nonempty_line(pubf)
+        validate_key(pubkey, f"client {name} pubkey")
+
+    # resolve ip octet
+    if ip is None:
+        octet = alloc_octet(cfg)
+    else:
+        ip = ip.strip()
+        if ip.startswith(cfg.client_net_prefix):
+            ip = ip[len(cfg.client_net_prefix) :]
+        if not ip.isdigit():
+            raise RuntimeError("--ip must be an octet (2..254) or full IP like 10.66.66.X")
+        octet = int(ip)
+        if octet < 2 or octet > 254:
+            raise RuntimeError("--ip must be 2..254")
+        if octet in used_octets(cfg):
+            raise RuntimeError(f"IP octet {octet} already used")
+
+    ipf.write_text(f"{octet}\n", encoding="utf-8")
+    chmod600_root(ipf)
+
+    print(f"OK: added peer {name} -> {cfg.client_net_prefix}{octet}/32")
+    generate_wg0_conf(cfg)
+    if not no_restart:
+        restart_wg()
+
+
+def del_client(cfg: Cfg, name: str, no_restart: bool):
+    ensure_dirs(cfg)
+    pubf = cfg.clients_dir / f"{name}.pub"
+    ipf = cfg.clients_dir / f"{name}.ip"
+    # keep .key on purpose
+    if pubf.exists():
+        pubf.unlink()
+    if ipf.exists():
+        ipf.unlink()
+    print(f"OK: removed peer {name} (pub/ip). Private key kept if existed.")
+    generate_wg0_conf(cfg)
+    if not no_restart:
+        restart_wg()
+
+
+def export_client_conf(cfg: Cfg, name: str, endpoint: Optional[str]):
+    ensure_dirs(cfg)
+    keyf = cfg.clients_dir / f"{name}.key"
+    ipf = cfg.clients_dir / f"{name}.ip"
+
+    if not keyf.exists():
+        raise RuntimeError(f"Missing {keyf}. Run gen-client {name} on server or create key on client.")
+    if not ipf.exists():
+        raise RuntimeError(f"Missing {ipf}. Run add {name} first.")
+    if not cfg.server_pub.exists():
+        raise RuntimeError("Missing server.pub. Run gen-server first.")
+
+    client_priv = read_first_nonempty_line(keyf)
+    validate_key(client_priv, f"client {name} private key")
+    server_pub = read_first_nonempty_line(cfg.server_pub)
+    validate_key(server_pub, "server public key")
+
+    octet = int(read_first_nonempty_line(ipf))
+    if endpoint is None:
+        endpoint = f"{detect_public_ip()}:{cfg.wg_port}"
+
+    out = cfg.clients_dir / f"{name}.conf"
+    content = "\n".join(
+        [
+            "[Interface]",
+            f"Address = {cfg.client_net_prefix}{octet}/32",
+            f"PrivateKey = {client_priv}",
+            "",
+            "[Peer]",
+            f"PublicKey = {server_pub}",
+            f"Endpoint = {endpoint}",
+            # Default: only reach the server's WG IP via tunnel.
+            "AllowedIPs = 10.66.66.1/32",
+            f"PersistentKeepalive = {cfg.keepalive}",
+            "",
+        ]
+    )
+    out.write_text(content, encoding="utf-8")
+    chmod600_root(out)
+    print(f"OK: wrote {out}")
+
+
+def cmd_list(cfg: Cfg):
+    ensure_dirs(cfg)
+    names = list_clients(cfg)
+    if not names:
+        print("(no clients)")
+        return
+    for n in names:
+        ipf = cfg.clients_dir / f"{n}.ip"
+        octet = read_first_nonempty_line(ipf) if ipf.exists() else "?"
+        print(f"{n}\t{cfg.client_net_prefix}{octet}/32")
+
+
+def cmd_show(cfg: Cfg, name: str):
+    ensure_dirs(cfg)
+    pubf = cfg.clients_dir / f"{name}.pub"
+    ipf = cfg.clients_dir / f"{name}.ip"
+    keyf = cfg.clients_dir / f"{name}.key"
+    print(f"Name: {name}")
+    if ipf.exists():
+        print(f"IP:   {cfg.client_net_prefix}{read_first_nonempty_line(ipf)}/32")
+    else:
+        print("IP:   (not assigned)")
+    if pubf.exists():
+        print(f"PUB:  {read_first_nonempty_line(pubf)}")
+    else:
+        print("PUB:  (missing)")
+    print(f"KEY:  {'exists' if keyf.exists() else 'missing'} ({keyf})")
+
+
+def main():
+    require_root()
+    cfg = Cfg()
+    p = argparse.ArgumentParser(prog="wg_serverctl.py")
+    sub = p.add_subparsers(dest="cmd", required=True)
+
+    s = sub.add_parser("gen-server")
+    s.add_argument("--force", action="store_true")
+
+    g = sub.add_parser("gen-client")
+    g.add_argument("name")
+    g.add_argument("--force", action="store_true")
+
+    a = sub.add_parser("add")
+    a.add_argument("name")
+    a.add_argument("--pubkey", help="Client public key (base64, ends with =)")
+    a.add_argument("--ip", help="IP octet (2..254) or full 10.66.66.X")
+    a.add_argument("--no-restart", action="store_true")
+
+    d = sub.add_parser("del")
+    d.add_argument("name")
+    d.add_argument("--no-restart", action="store_true")
+
+    ap = sub.add_parser("apply")
+    ap.add_argument("--no-restart", action="store_true")
+
+    sub.add_parser("list")
+
+    sh = sub.add_parser("show")
+    sh.add_argument("name")
+
+    ex = sub.add_parser("export")
+    ex.add_argument("name")
+    ex.add_argument("--endpoint", help="Override endpoint ip:port (default: auto-detect public ip)")
+
+    args = p.parse_args()
+
+    try:
+        if args.cmd == "gen-server":
+            gen_server(cfg, args.force)
+        elif args.cmd == "gen-client":
+            gen_client(cfg, args.name, args.force)
+        elif args.cmd == "add":
+            add_client(cfg, args.name, args.pubkey, args.ip, args.no_restart)
+        elif args.cmd == "del":
+            del_client(cfg, args.name, args.no_restart)
+        elif args.cmd == "apply":
+            generate_wg0_conf(cfg)
+            if not args.no_restart:
+                restart_wg()
+        elif args.cmd == "list":
+            cmd_list(cfg)
+        elif args.cmd == "show":
+            cmd_show(cfg, args.name)
+        elif args.cmd == "export":
+            export_client_conf(cfg, args.name, args.endpoint)
+        else:
+            p.print_help()
+    except Exception as e:
+        print(f"ERROR: {e}", file=sys.stderr)
+        sys.exit(1)
+
+
+if __name__ == "__main__":
+    main()
+