# project-bifrost

Invite-only Fenja AI entrance and archive. Node/Express + SQLite + SMTP,
behind Nginx on a VPS.

## Local development (Windows / VS Code)

```powershell
# 1. Install deps
npm install

# 2. Configure
copy .env.example .env
# Edit .env:
#   CODE_PEPPER  — generate with: openssl rand -hex 32
#                  (or any 64-char hex string; use the same one in prod)
#   SMTP_*       — your relay credentials
#   MAIL_FROM    — e.g. "Fenja AI <noreply@project-bifrost.fenja.ai>"

# 3. Invite yourself
node bin/invite.js add your@email.com

# 4. Run
npm run dev
# → http://127.0.0.1:3000

# 5. Walk the flow:
#    a) Open http://127.0.0.1:3000
#    b) Enter your invited email → receive code by mail
#    c) Type code → lands on /archive
#    d) Hit http://127.0.0.1:3000/archive directly in a private window:
#       should redirect to / (proves gating works)
```

## Deploying to the VPS

This assumes:
- VPS with Nginx already running and TLS for `project-bifrost.fenja.ai`
- Node 20+ installed
- A `fenja` system user owns `/opt/fenja`

### First-time setup

```bash
# On the VPS
sudo useradd -r -s /usr/sbin/nologin fenja
sudo mkdir -p /opt/fenja
sudo chown -R fenja:fenja /opt/fenja
```

### Pushing code from Windows

From the project root, sync with rsync (via WSL) or scp/WinSCP:

```powershell
# Example rsync (requires WSL or rsync on Windows)
rsync -avz --delete `
  --exclude node_modules --exclude data --exclude .env --exclude .git `
  ./ user@vps:/opt/fenja/
```

Then on the VPS:

```bash
cd /opt/fenja
sudo -u fenja npm ci --omit=dev
sudo chmod 750 /opt/fenja/protected
sudo chmod 750 /opt/fenja/data
```

Create `/opt/fenja/.env` in place (do NOT rsync it — keep secrets off your laptop):

```bash
sudo -u fenja nano /opt/fenja/.env
sudo chmod 600 /opt/fenja/.env
```

Install the systemd unit and Nginx config:

```bash
sudo cp deploy/fenja.service /etc/systemd/system/fenja.service
sudo systemctl daemon-reload
sudo systemctl enable --now fenja
sudo systemctl status fenja          # should be "active (running)"

sudo cp deploy/nginx.conf /etc/nginx/sites-available/project-bifrost
sudo ln -sf /etc/nginx/sites-available/project-bifrost \
            /etc/nginx/sites-enabled/project-bifrost
# Also ensure the rate-limit zone is declared — see deploy/nginx.conf for the one-liner
sudo nginx -t
sudo systemctl reload nginx
```

### Verifying from outside

```bash
curl -I https://project-bifrost.fenja.ai/
# 200 + HTML (the entrance)

curl -I https://project-bifrost.fenja.ai/archive
# 302 → /

curl -I https://project-bifrost.fenja.ai/protected/archive.html
# 404 (this URL literally does not exist)

curl -i -X POST https://project-bifrost.fenja.ai/auth/request-code \
     -H 'Content-Type: application/json' \
     -d '{"email":"nobody@example.com"}'
# 200 + {"ok":true}  (no mail is actually sent; endpoint doesn't leak)
```

### Managing invites on the server

```bash
sudo -u fenja node /opt/fenja/bin/invite.js add   someone@example.com
sudo -u fenja node /opt/fenja/bin/invite.js list
sudo -u fenja node /opt/fenja/bin/invite.js remove someone@example.com
```

### Backups

Add a cron job:

```
# /etc/cron.d/fenja-backup
0 3 * * * fenja sqlite3 /opt/fenja/data/fenja.sqlite ".backup /opt/fenja/data/backup-$(date +\%F).sqlite"
0 4 * * * fenja find /opt/fenja/data -name 'backup-*.sqlite' -mtime +14 -delete
```

`.backup` is safe on a live SQLite DB. `cp` is not.

## Project layout

```
project-bifrost/
├── package.json
├── server.js                 # entry point — binds 127.0.0.1:3000
├── .env.example              # copy to .env
├── .gitignore
├── bin/
│   └── invite.js             # CLI: add / remove / list invites
├── src/
│   ├── db.js                 # SQLite schema + prepared statements
│   ├── sessions.js           # codes, cookies, HMAC
│   ├── mail.js               # Nodemailer SMTP transport
│   ├── middleware.js         # rateLimit, requireAuth
│   └── auth.js               # /auth/* router
├── public/                   # served to anyone
│   └── index.html            # the Entrance page
├── protected/                # served only with a valid session cookie
│   └── archive.html          # placeholder for now; drop the real page here
├── data/                     # created on first run — SQLite lives here
└── deploy/
    ├── nginx.conf
    └── fenja.service
```

## Security model at a glance

- **Static HTML is never served from a public directory for `/archive`.** Node checks the session cookie *before* reading the file off disk. No cookie → 302 → / (the file bytes never leave the server).
- **The session cookie is `HttpOnly`, `Secure`, `SameSite=Lax`.** JavaScript on the page cannot read or steal it.
- **Sessions are opaque 256-bit random IDs** stored in SQLite. Revoking is a DELETE.
- **One-time codes are HMAC'd with a server-side pepper** (`CODE_PEPPER`) before storage. A DB leak alone cannot reveal codes.
- **Rate limits on everything.** 5 code requests per IP per hour, 20 verify attempts per IP per hour, 5 wrong guesses per code before it's nuked.
- **`/auth/request-code` always returns 200** — attackers cannot probe the invite list by email-enumeration.
- **Node binds to `127.0.0.1` only.** Nginx is the single ingress; there is no public Node port.
- **Strict CSP** blocks inline scripts and foreign origins from the gated pages.
