# AGENTS.md -- WireGuard Policy Firewall + WGRplane

**Generated:** 2026-05-08
**Project:** 03.wireguard-policy

## OVERVIEW
Hybrid project: (1) WireGuard Policy Firewall -- shell script iptables/ipset engine driven by `wg0.conf` `#Access` comments. (2) WGRplane -- Go binary (port 10087) serving REST API + Vue 3 SPA for WireGuard control plane management.

## STRUCTURE
```
03.wireguard-policy/
├── app/                    # WGRplane: Go backend + Vue 3 frontend (see app/AGENTS.md)
│   ├── *.go                # 13 Go files, flat package (no subdirs)
│   ├── frontend/           # Vue 3 SPA (see app/frontend/src/AGENTS.md)
│   └── docs/               # Swagger auto-generated (DO NOT EDIT)
├── wg-sync-policy.sh       # Parses wg0.conf → policy.json (atomic write + flock)
├── wg-policy-engine.sh     # Reads policy.json → iptables/ipset WG_POLICY chain
├── wg-sync-watch.sh        # inotifywait daemon, debounces wg0.conf changes
├── wg-policy-lib.sh        # Shared shell library (source only, never execute directly)
├── wg-policy-ctl           # CLI wrapper for operator use
├── wg-policy-cleanup.sh    # PostDown cleanup (run by WireGuard)
├── *.service / *.timer     # systemd units for daemon + health check
├── install.sh              # Unified installer (embeds all scripts, built by build.sh)
├── build.sh / build.bat    # Rebuilds install.sh from source scripts
├── Dockerfile              # Multi-stage: Go build + frontend build
└── README.md               # Full user documentation
```

## WHERE TO LOOK
| Task | Location |
|------|----------|
| Policy firewall logic | `wg-sync-policy.sh`, `wg-policy-engine.sh`, `wg-policy-lib.sh` |
| Firewall rule chain | `wg-policy-engine.sh` -- WG_POLICY iptables chain |
| Policy JSON schema | `wg-sync-policy.sh` output / `wg-policy-engine.sh` input |
| WGRplane API handlers | `app/handlers.go` |
| WGRplane DB models | `app/models.go` |
| Auth middleware | `app/auth.go` (CAUTION: see known issues) |
| nftables rules (forward mode) | `app/nftables.go` |
| Webhook delivery | `app/webhook.go` |
| Vue frontend | `app/frontend/src/` |
| i18n translations | `app/frontend/src/i18n/locales/` (en, id, zh) |
| Backend i18n | `app/active.{en,id,zh}.json` |
| Systemd service config | `wg-policy.service`, `wgrplane.service` |

## CRITICAL DESIGN RULES

### Policy Firewall -- `#Access` MUST NOT be changed
- WireGuard `AllowedIPs` on the server side = Cryptokey Routing, not firewall whitelist
- Putting destination IPs in server's `AllowedIPs` breaks routing (WG tunnels those packets INTO client)
- `#Access` comment is the ONLY correct way to declare firewall destinations per-peer
- **NEVER refactor to parse targets from `AllowedIPs`** -- architecturally incorrect

### Atomic Writes
- Always `mv -f tmp target` for `policy.json` -- never write directly
- `wg-sync-policy.sh` uses `flock` -- never bypass locking

### Rollback
- `wg-policy-engine.sh` creates `WG_POLICY_BAK` chain; traps `ERR` for rollback

### No SaveConfig
- WireGuard `SaveConfig = true` strips ALL comments including `#Access` -- NEVER enable

## KNOWN ISSUES / GOTCHAS
- **AuthMiddleware NOT applied**: `auth.go` defines `AuthMiddleware` but it is NOT wired to any routes in `main.go`. All API endpoints currently unprotected (auth header still checked inside handlers via manual if-check, but middleware chain is absent).
- **TOTP secrets in-memory**: `totpSecrets` map in `auth.go` is not persisted; lost on restart.
- **WebSocket stats are MOCK**: `stats.go` broadcasts randomly generated numbers, not real WireGuard traffic.
- **Plugin system is stub**: `plugins.go` TelegramNotifier/SlackNotifier just print to stdout.
- **Binary + DB in app/**: `wgrplane` binary and `wgrplane.db` live in `app/` (non-standard, intentional).
- **Duplicate i18n**: `app/active.*.json` (backend i18n) and `app/frontend/src/i18n/locales/` (frontend i18n) are separate systems.

## ANTI-PATTERNS
- Never parse firewall targets from `AllowedIPs` -- use `#Access` only
- Never write `policy.json` without atomic mv + flock
- Never run `wg-policy-lib.sh` directly (source-only library)
- Never enable `SaveConfig = true` in wg0.conf
- Do NOT edit `app/docs/docs.go` -- auto-generated by swaggo
- Do NOT put business logic in `app/main.go` -- it's bootstrap only

## COMMANDS

### Policy Firewall
```bash
wg-policy-ctl status    # Health: interface, JSON validity, rule counts
wg-policy-ctl validate  # Validate policy.json without applying
wg-policy-ctl rules     # Show active WG_POLICY iptables rules
wg-policy-ctl reload    # Force re-sync from wg0.conf + re-apply
wg-policy-ctl policy    # Show raw policy.json
wg-policy-ctl log       # Show dropped packet logs (rate-limited)
systemctl restart wg-policy.service
journalctl -u wg-policy.service -f
```

### WGRplane (Go App)
```bash
cd app && go build -o ../wgrplane .          # Build Go binary
cd app/frontend && npm install && npm run build  # Build Vue frontend
./wgrplane                                    # Run (serves :10087)
systemctl restart wgrplane.service
journalctl -u wgrplane.service -f
curl -H "wg-rplane-datadunia: test-api-key" http://localhost:10087/api/servers
```

### Installer
```bash
./build.sh           # Rebuild install.sh from source scripts (Linux)
./build.bat          # Rebuild install.sh from source scripts (Windows)
sudo ./install.sh install    # Full install (deps + scripts + systemd + service)
sudo ./install.sh uninstall  # Remove all
```

## DEPENDENCIES
- Shell: `jq`, `inotify-tools` (required); `ipset` (optional, O(1) lookup)
- Go: 1.25.1, SQLite (glebarez/sqlite), Gorilla Mux, GORM, JWT, TOTP, WebSocket
- Frontend: Vue 3, TypeScript, Vite, TailwindCSS 4, vue-i18n 9
- Auth headers: `wg-rplane-datadunia: <KEY>` (API key) | `Authorization: Bearer <JWT>` | `X-TOTP: <CODE>`
- Env vars: `WG_API_KEY` (default: test-api-key), `JWT_SECRET`, `WG_RPLANE_MODE` (forward|standalone), `APP_FRONTEND_DIR`