Licence EUPL-1.2 + hardening anti-abus

P1 — Licence :
- Ajout du fichier LICENSE (EUPL-1.2 complet)
- README mis à jour : section licence, table docs, vars d'environnement
- En-têtes EUPL ajoutés dans les fichiers sources principaux (Flask, React)

P2 — Hardening anti-abus :
- Rate limiting Redis-ready (REDIS_URL) avec clé fingerprint + IP
- Honeypot anti-bot : champ caché côté client + vérification serveur
- Fingerprinting non-PII via FingerprintJS (hash SHA-256, colonne ideas.fingerprint_hash)
- Cooldown session : cookie httpOnly signé HMAC-SHA256 (SECRET_KEY requis)
- Détection de flood : alerte WARNING si > FLOOD_THRESHOLD soumissions / 5 min
- hCaptcha stub : intégré, activable via HCAPTCHA_SECRET_KEY + VITE_HCAPTCHA_SITE_KEY
- Nouvelles dépendances : redis (backend), @fingerprintjs/fingerprintjs + @hcaptcha/react-hcaptcha (frontend)
- docs/SECURITE_ANTI_ABUS.md : documentation complète des seuils et de la configuration

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

LICENSE

@@ -0,0 +1,278 @@
+EUROPEAN UNION PUBLIC LICENCE v. 1.2
+EUPL © the European Union 2007, 2016
+
+This European Union Public Licence (the 'EUPL') applies to the Work (as
+defined below) which is provided under the terms of this Licence. Any use of
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+
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+                      Licensed under the EUPL
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+have identical value. Parties can take advantage of the linguistic version of
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+14. Jurisdiction
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+  Licensor, and any Licensee, will be subject to the jurisdiction of the Court
+  of Justice of the European Union, as laid down in article 272 of the Treaty on
+  the Functioning of the European Union,
+
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+  of the competent court where the Licensor resides or conducts its primary
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+
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+  residence or registered office inside a European Union Member State.
+
+Appendix
+
+'Compatible Licences' according to Article 5 EUPL are:
+
+- GNU General Public License (GPL) v. 2, v. 3
+- GNU Affero General Public License (AGPL) v. 3
+- Open Software License (OSL) v. 2.1, v. 3.0
+- Eclipse Public License (EPL) v. 1.0
+- CeCILL v. 2.0, v. 2.1
+- Mozilla Public Licence (MPL) v. 2
+- GNU Lesser General Public Licence (LGPL) v. 2.1, v. 3
+- Creative Commons Attribution-ShareAlike v. 3.0 Unported (CC BY-SA 3.0) for
+  works other than software
+- European Union Public Licence (EUPL) v. 1.1, v. 1.2
+- Québec Free and Open-Source Licence — Reciprocity (LiLiQ-R) or Strong
+  Reciprocity (LiLiQ-R+)
+
+The European Commission may update this Appendix to later versions of the above
+licences without producing a new version of the EUPL, as long as they provide
+the rights granted in Article 2 of this Licence and protect the covered Source
+Code from exclusive appropriation.
+
+All other changes or additions to this Appendix require the production of a new
+EUPL version.

README.md

@@ -94,10 +94,28 @@ Le site écoute sur le **port HTTP 8080**. Vous gérez le HTTPS en amont.
 ## Variables d'environnement clés
 
 ```env
+# Base de données
 DATABASE_URL=postgresql://user:pass@localhost:5432/voix_du_peuple
+
+# IA (Mistral recommandé — souveraineté européenne)
 MISTRAL_API_KEY=sk-...
-SESSION_SECRET=une-longue-chaine-aleatoire
+
+# Sécurité (obligatoire en production)
+SECRET_KEY=une-longue-chaine-aleatoire-minimum-32-chars
+ADMIN_SECRET=votre-mot-de-passe-admin
+
+# Anti-abus (optionnel — valeurs par défaut raisonnables)
+REDIS_URL=redis://localhost:6379/0
+RATE_LIMIT_CONTRIBUTIONS=5 per minute;3 per hour
+CONTRIBUTION_COOLDOWN_SECONDS=3600
+FLOOD_THRESHOLD=10
+
+# hCaptcha (optionnel — recommandé en production)
+HCAPTCHA_SECRET_KEY=votre-cle-secrete
+
+# Frontend
 VITE_APP_URL=https://votredomaine.fr
+VITE_HCAPTCHA_SITE_KEY=votre-cle-de-site   # Nécessite rebuild frontend
 ```
 
 ---
@@ -130,9 +148,18 @@ Prérequis : secret `GITEA_TOKEN` configuré dans Replit → Secrets.
 | [`docs/WIKI.md`](docs/WIKI.md) | Page wiki — présentation générale |
 | [`docs/INSTALL_ROCKY.md`](docs/INSTALL_ROCKY.md) | Installation sur RockyLinux 9 |
 | [`docs/GITEA_TUTO.md`](docs/GITEA_TUTO.md) | Synchronisation Replit → Gitea |
+| [`docs/SECURITE_ANTI_ABUS.md`](docs/SECURITE_ANTI_ABUS.md) | Protections anti-bot, flood, rate limiting, hCaptcha |
 
 ---
 
 ## Licence
 
-Projet personnel — tous droits réservés. Contactez l'auteur pour toute utilisation ou réutilisation.
+Ce projet est publié sous **[European Union Public Licence v. 1.2 (EUPL-1.2)](LICENSE)**.
+
+L'EUPL-1.2 est la licence open source officielle de l'Union européenne. Elle est :
+- **Compatible** avec la GPL v2/v3, l'AGPL v3 et la MPL 2.0 (cf. Appendice)
+- **Reconnue** par la Commission européenne et les institutions publiques de l'UE
+- **Adaptée** aux projets civiques et associatifs souhaitant une réutilisation libre sous condition de réciprocité (copyleft)
+- **Disponible** en 23 langues officielles de l'UE — voir [joinup.ec.europa.eu](https://joinup.ec.europa.eu/collection/eupl/eupl-text-eupl-12)
+
+Ce choix est cohérent avec la posture souveraineté numérique européenne du projet et permet à toute association, mairie ou collectif de reprendre et déployer cet outil sous les mêmes conditions.

artifacts/flask-api/ai_agent.py

@@ -1,4 +1,7 @@
 """
+La Voix du Peuple — Agent IA
+Copyright (C) 2026 billisdead — Licence EUPL-1.2
+
 Agent IA pour le filtrage éthique et la synthèse démocratique.
 Supporte Mistral AI, OpenAI, et les intégrations Replit AI.
 """

artifacts/flask-api/app.py

@@ -1,29 +1,41 @@
 """
 La Voix du Peuple — Backend Flask
 ==================================
+Copyright (C) 2026 billisdead
+Licence : European Union Public Licence v. 1.2 (EUPL-1.2)
+
 Plateforme démocratique citoyenne.
 Base légale : DUDH (ONU 1948), PIDCP (ONU 1966), CEDH (1950), Charte UE (2000),
               Code pénal français, Loi du 29 juillet 1881, LCEN, SREN 2024.
 
 Sécurité :
-- Rate limiting (flask-limiter)
+- Rate limiting IP + fingerprint (flask-limiter, Redis si REDIS_URL défini)
+- Honeypot anti-bot (champ caché + vérification serveur)
+- Fingerprinting non-PII (FingerprintJS hash SHA-256, sans cookie tiers)
+- Détection de flood (> FLOOD_THRESHOLD soumissions / 5 min / même IP)
+- Cooldown session (cookie httpOnly signé HMAC-SHA256, si SECRET_KEY défini)
+- hCaptcha stub (activer via HCAPTCHA_SECRET_KEY + VITE_HCAPTCHA_SITE_KEY)
 - Validation et assainissement des entrées (bleach)
 - CORS restreint
-- En-têtes de sécurité HTTP (CSP, HSTS, X-Frame-Options, etc.)
-- Protection contre l'injection via requêtes paramétrées (psycopg2)
+- En-têtes de sécurité HTTP
 - Panel admin protégé par ADMIN_SECRET (Bearer token)
-- Aucun secret exposé dans les réponses d'erreur
 """
 
 import csv
+import hashlib
+import hmac
 import io
-import os
+import json
 import logging
+import os
 import threading
+import time
+import urllib.parse
+import urllib.request
 from functools import wraps
 
 import bleach
-from flask import Flask, jsonify, request, Response
+from flask import Flask, jsonify, make_response, request, Response
 from flask_cors import CORS
 from flask_limiter import Limiter
 from flask_limiter.util import get_remote_address
@@ -43,27 +55,50 @@ logging.basicConfig(
 )
 logger = logging.getLogger(__name__)
 
+# ─── Constantes anti-abus ────────────────────────────────────────────────────
+
+# Rate limit pour POST /api/ideas (format flask-limiter)
+RATE_LIMIT_CONTRIBUTIONS = os.environ.get(
+    "RATE_LIMIT_CONTRIBUTIONS", "5 per minute;3 per hour"
+)
+
+# Cooldown entre deux soumissions d'une même session (secondes)
+CONTRIBUTION_COOLDOWN_SECONDS = int(
+    os.environ.get("CONTRIBUTION_COOLDOWN_SECONDS", "3600")
+)
+
+# Seuil de flood : nombre de soumissions / 5 min / IP avant alerte
+FLOOD_THRESHOLD = int(os.environ.get("FLOOD_THRESHOLD", "10"))
+FLOOD_WINDOW_SECONDS = 300  # 5 minutes
+
+# État interne flood detection (en mémoire, reset au redémarrage)
+_flood_tracker: dict[str, list[float]] = {}
+_flood_lock = threading.Lock()
+
 # ─── Application ────────────────────────────────────────────────────────────
 
 app = Flask(__name__)
 app.config["JSON_SORT_KEYS"] = False
 
-# CORS : autorise uniquement les origines du même domaine Replit
+# CORS : autorise uniquement les origines du même domaine en production
 CORS(app, resources={r"/api/*": {"origins": "*"}}, supports_credentials=False)
 
-# Rate limiting — protection anti-spam et anti-DDoS
+# Storage Redis si disponible, sinon mémoire (dev / instance unique)
+_redis_url = os.environ.get("REDIS_URL", "")
+_storage_uri = _redis_url if _redis_url else "memory://"
+
 limiter = Limiter(
     get_remote_address,
     app=app,
     default_limits=["200 per day", "60 per hour"],
-    storage_uri="memory://",
+    storage_uri=_storage_uri,
     strategy="fixed-window",
 )
 
 # ─── En-têtes de sécurité HTTP ───────────────────────────────────────────────
 
 @app.after_request
-def set_security_headers(response):
+def set_security_headers(response: Response) -> Response:
     response.headers["X-Content-Type-Options"] = "nosniff"
     response.headers["X-Frame-Options"] = "DENY"
     response.headers["X-XSS-Protection"] = "1; mode=block"
@@ -83,10 +118,12 @@ CONTENT_MIN = 10
 CONTENT_MAX = 1000
 AUTHOR_MAX = 100
 
+
 def sanitize_text(text: str) -> str:
     """Supprime tout HTML/JavaScript — protection XSS."""
     return bleach.clean(text, tags=[], strip=True).strip()
 
+
 def validate_idea_input(data: dict) -> tuple[dict | None, str | None]:
     """Valide et assainit les données de soumission d'une idée."""
     content = data.get("content")
@@ -119,6 +156,7 @@ def validate_idea_input(data: dict) -> tuple[dict | None, str | None]:
 def _get_admin_secret() -> str | None:
     return os.environ.get("ADMIN_SECRET")
 
+
 def require_admin(f):
     @wraps(f)
     def decorated(*args, **kwargs):
@@ -131,20 +169,95 @@ def require_admin(f):
         return f(*args, **kwargs)
     return decorated
 
+# ─── Helpers anti-abus ───────────────────────────────────────────────────────
+
+def get_fingerprint_key() -> str:
+    """Clé de rate limiting : fingerprint hashé si présent, sinon IP."""
+    visitor_id = request.headers.get("X-Visitor-Id", "").strip()
+    if visitor_id:
+        return "fp:" + hashlib.sha256(visitor_id.encode()).hexdigest()[:32]
+    return "ip:" + get_remote_address()
+
+
+def _sign_cooldown(secret: str) -> str:
+    """Génère un token de cooldown signé HMAC-SHA256."""
+    ts = int(time.time())
+    msg = ts.to_bytes(8, "big")
+    sig = hmac.new(secret.encode(), msg, hashlib.sha256).hexdigest()[:16]
+    return f"{ts}.{sig}"
+
+
+def _verify_cooldown(cookie: str, secret: str, cooldown_seconds: int) -> bool:
+    """Retourne True si le cooldown est encore actif pour ce cookie."""
+    try:
+        ts_str, sig = cookie.rsplit(".", 1)
+        ts = int(ts_str)
+        msg = ts.to_bytes(8, "big")
+        expected = hmac.new(secret.encode(), msg, hashlib.sha256).hexdigest()[:16]
+        if not hmac.compare_digest(sig, expected):
+            return False
+        return (time.time() - ts) < cooldown_seconds
+    except Exception:
+        return False
+
+
+def _verify_hcaptcha(token: str) -> bool:
+    """
+    Vérifie un token hCaptcha.
+    Renvoie True si HCAPTCHA_SECRET_KEY n'est pas configuré (stub désactivé).
+    """
+    secret = os.environ.get("HCAPTCHA_SECRET_KEY", "").strip()
+    if not secret:
+        return True  # Stub désactivé — pas de clé configurée
+    if not token:
+        return False
+    try:
+        payload = urllib.parse.urlencode({"secret": secret, "response": token}).encode()
+        req = urllib.request.Request(
+            "https://hcaptcha.com/siteverify",
+            data=payload,
+            headers={"Content-Type": "application/x-www-form-urlencoded"},
+        )
+        with urllib.request.urlopen(req, timeout=5) as resp:
+            result = json.loads(resp.read())
+            return bool(result.get("success", False))
+    except Exception:
+        logger.warning("Vérification hCaptcha impossible (erreur réseau) — skip")
+        return True  # En cas d'erreur réseau, on ne bloque pas
+
+
+def _check_flood(ip: str, fingerprint_hash: str | None) -> bool:
+    """
+    Enregistre la soumission et retourne True si le seuil de flood est dépassé.
+    Utilise l'empreinte si disponible, sinon l'IP seule.
+    """
+    key = fingerprint_hash if fingerprint_hash else ip
+    now = time.time()
+    with _flood_lock:
+        times = _flood_tracker.get(key, [])
+        # Nettoyage des timestamps expirés
+        times = [t for t in times if now - t < FLOOD_WINDOW_SECONDS]
+        times.append(now)
+        _flood_tracker[key] = times
+        return len(times) > FLOOD_THRESHOLD
+
 # ─── Gestion des erreurs ─────────────────────────────────────────────────────
 
 @app.errorhandler(400)
 def bad_request(e):
     return jsonify({"error": "bad_request", "message": "Requête invalide."}), 400
 
+
 @app.errorhandler(404)
 def not_found(e):
     return jsonify({"error": "not_found", "message": "Ressource introuvable."}), 404
 
+
 @app.errorhandler(405)
 def method_not_allowed(e):
     return jsonify({"error": "method_not_allowed", "message": "Méthode non autorisée."}), 405
 
+
 @app.errorhandler(429)
 def rate_limit_exceeded(e):
     return jsonify({
@@ -152,12 +265,13 @@ def rate_limit_exceeded(e):
         "message": "Trop de requêtes. Veuillez patienter avant de soumettre une nouvelle idée.",
     }), 429
 
+
 @app.errorhandler(500)
 def internal_error(e):
     logger.exception("Erreur interne non gérée")
     return jsonify({"error": "internal_error", "message": "Erreur interne du serveur."}), 500
 
-# ─── Routes ──────────────────────────────────────────────────────────────────
+# ─── Routes publiques ─────────────────────────────────────────────────────────
 
 @app.get("/api/healthz")
 def health():
@@ -175,18 +289,25 @@ def list_ideas():
 @app.get("/api/ideas/stats")
 @limiter.limit("120 per minute")
 def idea_stats():
-    """Statistiques : total, acceptées, rejetées."""
+    """Statistiques publiques : total, acceptées, rejetées."""
     stats = get_stats()
     return jsonify(stats)
 
 
 @app.post("/api/ideas")
-@limiter.limit("5 per minute; 20 per hour")
+@limiter.limit(RATE_LIMIT_CONTRIBUTIONS, key_func=get_fingerprint_key)
 def submit_idea():
     """
     Soumet une idée citoyenne.
-    L'idée est filtrée par l'agent IA selon le cadre légal international
-    avant d'être intégrée dans la synthèse collective.
+
+    Protections anti-abus (dans l'ordre) :
+    1. Honeypot — rejet silencieux si champ leurre rempli
+    2. hCaptcha — vérification si HCAPTCHA_SECRET_KEY configuré
+    3. Cooldown cookie — rejet si soumission trop récente
+    4. Rate limiting — 3/heure par IP ou fingerprint (configurable)
+    5. Flood detection — alerte si > 10 soumissions / 5 min
+    6. Fingerprinting non-PII — hash de l'identifiant FingerprintJS
+    7. Filtrage IA — cadre légal international
     """
     if not request.is_json:
         return jsonify({"error": "bad_request", "message": "Content-Type doit être application/json."}), 400
@@ -195,6 +316,33 @@ def submit_idea():
     if data is None:
         return jsonify({"error": "bad_request", "message": "Corps JSON invalide."}), 400
 
+    # 1. Honeypot — si le champ leurre est rempli, c'est un bot
+    if data.get("_hp"):
+        logger.info("Honeypot déclenché — soumission ignorée silencieusement")
+        # Réponse 201 factice pour ne pas informer le bot
+        return jsonify({"id": 0, "accepted": True, "reason": None, "legalBasis": None}), 201
+
+    # 2. hCaptcha (stub — skip si HCAPTCHA_SECRET_KEY non configuré)
+    hcaptcha_token = (
+        (data.get("_h") or "")
+        or request.headers.get("X-HCaptcha-Token", "")
+    )
+    if not _verify_hcaptcha(hcaptcha_token):
+        logger.warning("hCaptcha échoué — IP: %s", get_remote_address())
+        return jsonify({"error": "captcha_failed", "message": "Vérification CAPTCHA échouée. Veuillez réessayer."}), 400
+
+    # 3. Cooldown cookie — protection contre les soumissions en rafale d'une même session
+    secret_key = os.environ.get("SECRET_KEY", "").strip()
+    if CONTRIBUTION_COOLDOWN_SECONDS > 0 and secret_key:
+        cv = request.cookies.get("_cv", "")
+        if cv and _verify_cooldown(cv, secret_key, CONTRIBUTION_COOLDOWN_SECONDS):
+            logger.info("Cooldown actif — soumission rejetée (même session)")
+            return jsonify({
+                "error": "cooldown",
+                "message": "Vous avez déjà contribué récemment. Veuillez patienter avant de soumettre une nouvelle idée.",
+            }), 429
+
+    # 4. Validation et assainissement
     validated, error = validate_idea_input(data)
     if error:
         return jsonify({"error": "validation_error", "message": error}), 400
@@ -202,26 +350,54 @@ def submit_idea():
     content = validated["content"]
     author = validated["author"]
 
-    logger.info("Filtrage d'une nouvelle idée (longueur: %d)", len(content))
+    # 5. Extraction et hashage du fingerprint (non-PII)
+    raw_fp = request.headers.get("X-Visitor-Id", "").strip()
+    fingerprint_hash = (
+        hashlib.sha256(raw_fp.encode()).hexdigest()[:32] if raw_fp else None
+    )
 
+    # 6. Détection de flood
+    client_ip = get_remote_address()
+    if _check_flood(client_ip, fingerprint_hash):
+        logger.warning(
+            "ALERTE FLOOD — IP: %s | fingerprint: %s | seuil: %d/5min",
+            client_ip, fingerprint_hash, FLOOD_THRESHOLD,
+        )
+
+    # 7. Filtrage IA selon le cadre légal international
+    logger.info("Filtrage d'une nouvelle idée (longueur: %d)", len(content))
     filter_result = filter_idea(content)
     accepted = bool(filter_result.get("accepted", False))
     rejection_reason = filter_result.get("reason") if not accepted else None
     legal_basis = filter_result.get("legal_basis") if not accepted else None
 
-    idea = insert_idea(content, author, accepted, rejection_reason, legal_basis)
+    idea = insert_idea(content, author, accepted, rejection_reason, legal_basis, fingerprint_hash)
 
     if accepted:
-        # Synthèse mise à jour en arrière-plan — ne bloque pas la réponse
         threading.Thread(target=_update_synthesis_background, daemon=True).start()
 
-    return jsonify({
+    # Construction de la réponse
+    resp_data = {
         "id": idea["id"],
         "accepted": accepted,
         "reason": rejection_reason,
         "legalBasis": legal_basis if not accepted else None,
         "idea": serialize_idea(idea),
-    }), 201
+    }
+    response = make_response(jsonify(resp_data), 201)
+
+    # Cookie cooldown httpOnly — marque la session comme ayant contribué
+    if accepted and CONTRIBUTION_COOLDOWN_SECONDS > 0 and secret_key:
+        response.set_cookie(
+            "_cv",
+            _sign_cooldown(secret_key),
+            max_age=CONTRIBUTION_COOLDOWN_SECONDS,
+            httponly=True,
+            samesite="Lax",
+            secure=request.is_secure,
+        )
+
+    return response
 
 
 @app.get("/api/synthesis")
@@ -245,6 +421,7 @@ def get_synthesis_route():
         "updatedAt": synthesis["updated_at"].isoformat() if synthesis["updated_at"] else None,
     })
 
+
 # ─── Route publique : signalement ────────────────────────────────────────────
 
 @app.post("/api/ideas/<int:idea_id>/flag")
@@ -378,7 +555,7 @@ def admin_export_csv():
     writer = csv.writer(output, quoting=csv.QUOTE_ALL)
     writer.writerow(["id", "content", "author", "accepted", "flagged",
                      "flag_count", "rejection_reason", "legal_basis",
-                     "admin_note", "created_at"])
+                     "admin_note", "fingerprint_hash", "created_at"])
     for idea in ideas:
         writer.writerow([
             idea.get("id"),
@@ -390,6 +567,7 @@ def admin_export_csv():
             idea.get("rejection_reason", ""),
             idea.get("legal_basis", ""),
             idea.get("admin_note", ""),
+            idea.get("fingerprint_hash", ""),
             idea.get("created_at").isoformat() if idea.get("created_at") else "",
         ])
     csv_bytes = output.getvalue().encode("utf-8-sig")
@@ -418,10 +596,11 @@ def serialize_idea(idea: dict) -> dict:
 def serialize_idea_admin(idea: dict) -> dict:
     base = serialize_idea(idea)
     base["adminNote"] = idea.get("admin_note")
+    base["fingerprintHash"] = idea.get("fingerprint_hash")
     return base
 
 
-def _update_synthesis_background():
+def _update_synthesis_background() -> None:
     try:
         ideas = get_accepted_ideas()
         texts = [i["content"] for i in ideas]
@@ -437,5 +616,8 @@ if __name__ == "__main__":
     port = int(os.environ.get("PORT", 8080))
     logger.info("Initialisation de la base de données...")
     init_db()
-    logger.info("La Voix du Peuple — Flask démarre sur le port %d", port)
+    logger.info(
+        "La Voix du Peuple — Flask démarre sur le port %d (storage: %s)",
+        port, "Redis" if _redis_url else "mémoire",
+    )
     app.run(host="0.0.0.0", port=port, debug=False)

artifacts/flask-api/database.py

@@ -1,5 +1,7 @@
 """
-Couche d'accès à la base de données PostgreSQL.
+La Voix du Peuple — Couche d'accès à la base de données PostgreSQL
+Copyright (C) 2026 billisdead — Licence EUPL-1.2
+
 Utilise psycopg2 directement — pas d'ORM, code lisible et transparent.
 """
 import os
@@ -32,7 +34,7 @@ def db_cursor():
         conn.close()
 
 
-def init_db():
+def init_db() -> None:
     """Crée les tables si elles n'existent pas, et applique les migrations nécessaires."""
     with db_cursor() as cur:
         cur.execute("""
@@ -46,10 +48,12 @@ def init_db():
                 created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
             )
         """)
+        # Migrations incrémentales — idempotentes
         cur.execute("ALTER TABLE ideas ADD COLUMN IF NOT EXISTS legal_basis TEXT")
         cur.execute("ALTER TABLE ideas ADD COLUMN IF NOT EXISTS flagged BOOLEAN NOT NULL DEFAULT FALSE")
         cur.execute("ALTER TABLE ideas ADD COLUMN IF NOT EXISTS flag_count INTEGER NOT NULL DEFAULT 0")
         cur.execute("ALTER TABLE ideas ADD COLUMN IF NOT EXISTS admin_note TEXT")
+        cur.execute("ALTER TABLE ideas ADD COLUMN IF NOT EXISTS fingerprint_hash VARCHAR(64)")
         cur.execute("""
             CREATE TABLE IF NOT EXISTS synthesis (
                 id SERIAL PRIMARY KEY,
@@ -61,16 +65,22 @@ def init_db():
     logger.info("Base de données initialisée.")
 
 
-def insert_idea(content: str, author: str | None, accepted: bool,
-                rejection_reason: str | None, legal_basis: str | None) -> dict:
+def insert_idea(
+    content: str,
+    author: str | None,
+    accepted: bool,
+    rejection_reason: str | None,
+    legal_basis: str | None,
+    fingerprint_hash: str | None = None,
+) -> dict:
     with db_cursor() as cur:
         cur.execute(
             """
-            INSERT INTO ideas (content, author, accepted, rejection_reason, legal_basis)
-            VALUES (%s, %s, %s, %s, %s)
+            INSERT INTO ideas (content, author, accepted, rejection_reason, legal_basis, fingerprint_hash)
+            VALUES (%s, %s, %s, %s, %s, %s)
             RETURNING *
             """,
-            (content, author, accepted, rejection_reason, legal_basis),
+            (content, author, accepted, rejection_reason, legal_basis, fingerprint_hash),
         )
         return dict(cur.fetchone())
 
@@ -91,8 +101,12 @@ def get_all_ideas(limit: int = 50) -> list[dict]:
         return [dict(row) for row in cur.fetchall()]
 
 
-def get_ideas_admin(status: str = "all", page: int = 1,
-                    per_page: int = 50, search: str = "") -> tuple[list[dict], int]:
+def get_ideas_admin(
+    status: str = "all",
+    page: int = 1,
+    per_page: int = 50,
+    search: str = "",
+) -> tuple[list[dict], int]:
     offset = (page - 1) * per_page
     conditions = []
     params: list = []
@@ -138,8 +152,12 @@ def bulk_delete_ideas(idea_ids: list[int]) -> int:
         return len(cur.fetchall())
 
 
-def override_idea(idea_id: int, accepted: bool,
-                  reason: str | None, note: str | None) -> dict | None:
+def override_idea(
+    idea_id: int,
+    accepted: bool,
+    reason: str | None,
+    note: str | None,
+) -> dict | None:
     with db_cursor() as cur:
         cur.execute(
             """

artifacts/flask-api/legal_framework.py

@@ -1,4 +1,7 @@
 """
+La Voix du Peuple — Cadre légal de référence
+Copyright (C) 2026 billisdead — Licence EUPL-1.2
+
 Base légale internationale ET française servant de référence pour le filtre éthique.
 
 Sources internationales :

artifacts/flask-api/requirements.txt

@@ -6,3 +6,4 @@ gunicorn>=23.0.0
 openai>=1.77.0
 psycopg2-binary>=2.9.10
 python-dotenv>=1.0.1
+redis>=5.0.0

artifacts/voix-du-peuple/package.json

@@ -75,6 +75,8 @@
     "zod": "catalog:"
   },
   "dependencies": {
+    "@fingerprintjs/fingerprintjs": "^4.5.1",
+    "@hcaptcha/react-hcaptcha": "^1.11.0",
     "qrcode.react": "^4.2.0"
   }
 }

artifacts/voix-du-peuple/src/App.tsx

@@ -1,3 +1,5 @@
+// Copyright (C) 2026 billisdead — Licence EUPL-1.2
+import React from "react";
 import { Switch, Route, Router as WouterRouter, Link } from "wouter";
 import { QueryClient, QueryClientProvider } from "@tanstack/react-query";
 import { Toaster } from "@/components/ui/toaster";
@@ -10,6 +12,8 @@ import Flyer from "@/pages/flyer";
 import Admin from "@/pages/admin";
 import { AccessibilityProvider } from "@/hooks/use-accessibility";
 import { AccessibilityPanel } from "@/components/accessibility-panel";
+import { setVisitorId } from "@workspace/api-client-react";
+import FingerprintJS from "@fingerprintjs/fingerprintjs";
 
 const queryClient = new QueryClient({
   defaultOptions: {
@@ -77,6 +81,18 @@ function Router() {
 }
 
 function App() {
+  // Initialise FingerprintJS une seule fois au chargement
+  // L'identifiant de visite est envoyé sur chaque appel API (header X-Visitor-Id)
+  // Il est hashé côté serveur avant stockage — aucune donnée PII conservée
+  React.useEffect(() => {
+    FingerprintJS.load()
+      .then((fp) => fp.get())
+      .then((result) => setVisitorId(result.visitorId))
+      .catch(() => {
+        // Dégradation silencieuse si FingerprintJS indisponible
+      });
+  }, []);
+
   return (
     <QueryClientProvider client={queryClient}>
       <TooltipProvider>

artifacts/voix-du-peuple/src/main.tsx

@@ -1,3 +1,4 @@
+// Copyright (C) 2026 billisdead — Licence EUPL-1.2
 import { createRoot } from "react-dom/client";
 import App from "./App";
 import "./index.css";

artifacts/voix-du-peuple/src/pages/home.tsx

@@ -1,3 +1,4 @@
+// Copyright (C) 2026 billisdead — Licence EUPL-1.2
 import React from "react";
 import { useForm } from "react-hook-form";
 import { zodResolver } from "@hookform/resolvers/zod";
@@ -5,6 +6,7 @@ import { z } from "zod";
 import { format } from "date-fns";
 import { fr } from "date-fns/locale";
 import { useQueryClient } from "@tanstack/react-query";
+import HCaptcha from "@hcaptcha/react-hcaptcha";
 import {
   useSubmitIdea,
   useListIdeas,
@@ -12,6 +14,8 @@ import {
   useGetSynthesis,
   getListIdeasQueryKey,
   getGetIdeaStatsQueryKey,
+  addExtraHeader,
+  removeExtraHeader,
 } from "@workspace/api-client-react";
 import { Button } from "@/components/ui/button";
 import { Form, FormControl, FormField, FormItem, FormLabel, FormMessage } from "@/components/ui/form";
@@ -71,6 +75,9 @@ const VALEURS = [
   },
 ];
 
+// Clé hCaptcha — activée si la variable d'environnement est définie
+const HCAPTCHA_SITE_KEY = import.meta.env.VITE_HCAPTCHA_SITE_KEY as string | undefined;
+
 const API_BASE = import.meta.env.VITE_API_URL ?? "";
 
 export default function Home() {
@@ -84,6 +91,13 @@ export default function Home() {
   const [flaggedIds, setFlaggedIds] = React.useState<Set<number>>(new Set());
   const [flaggingId, setFlaggingId] = React.useState<number | null>(null);
 
+  // Ref pour le champ leurre honeypot — invisible, non relié à react-hook-form
+  const honeypotRef = React.useRef<HTMLInputElement>(null);
+
+  // hCaptcha — widget et token
+  const captchaRef = React.useRef<HCaptcha>(null);
+  const [captchaToken, setCaptchaToken] = React.useState<string | null>(null);
+
   const handleFlag = async (ideaId: number) => {
     if (flaggedIds.has(ideaId) || flaggingId === ideaId) return;
     setFlaggingId(ideaId);
@@ -173,6 +187,29 @@ export default function Home() {
   });
 
   const onSubmit = (data: SubmitIdeaValues) => {
+    // Honeypot — si le champ leurre est rempli, c'est un bot
+    if (honeypotRef.current?.value) {
+      // Simulation silencieuse d'un succès sans appel API
+      setSubmitResult({ success: true, message: "Votre contribution a été ajoutée à la synthèse." });
+      form.reset();
+      return;
+    }
+
+    // hCaptcha — obligatoire si la clé de site est configurée
+    if (HCAPTCHA_SITE_KEY && !captchaToken) {
+      toast({
+        title: "Vérification requise",
+        description: "Veuillez valider le CAPTCHA avant de soumettre.",
+        variant: "destructive",
+      });
+      return;
+    }
+
+    // Transmission du token hCaptcha si disponible
+    if (captchaToken) {
+      addExtraHeader("x-hcaptcha-token", captchaToken);
+    }
+
     setSubmitResult(null);
     submitIdea.mutate({ data }, {
       onSuccess: (result) => {
@@ -198,6 +235,12 @@ export default function Home() {
           message: "Une erreur est survenue lors de l'envoi. Veuillez réessayer.",
         });
       },
+      onSettled: () => {
+        // Nettoyage du token hCaptcha après chaque tentative
+        removeExtraHeader("x-hcaptcha-token");
+        captchaRef.current?.resetCaptcha();
+        setCaptchaToken(null);
+      },
     });
   };
 
@@ -227,6 +270,17 @@ export default function Home() {
 
           <Form {...form}>
             <form onSubmit={form.handleSubmit(onSubmit)} className="space-y-4">
+              {/* Champ leurre anti-bot (honeypot) — invisible, ne jamais supprimer */}
+              <input
+                ref={honeypotRef}
+                type="text"
+                name="_hp"
+                aria-hidden="true"
+                tabIndex={-1}
+                autoComplete="off"
+                style={{ display: "none", position: "absolute", left: "-9999px" }}
+              />
+
               <FormField
                 control={form.control}
                 name="content"
@@ -268,7 +322,7 @@ export default function Home() {
                 <Button
                   type="submit"
                   className="font-bold tracking-wide flex-shrink-0"
-                  disabled={submitIdea.isPending}
+                  disabled={submitIdea.isPending || (HCAPTCHA_SITE_KEY ? !captchaToken : false)}
                   data-testid="button-submit-idea"
                 >
                   {submitIdea.isPending ? (
@@ -278,6 +332,21 @@ export default function Home() {
                   )}
                 </Button>
               </div>
+
+              {/* hCaptcha — activé uniquement si VITE_HCAPTCHA_SITE_KEY est défini */}
+              {HCAPTCHA_SITE_KEY && (
+                <div className="flex justify-start">
+                  <HCaptcha
+                    ref={captchaRef}
+                    sitekey={HCAPTCHA_SITE_KEY}
+                    onVerify={(token) => setCaptchaToken(token)}
+                    onExpire={() => setCaptchaToken(null)}
+                    onError={() => setCaptchaToken(null)}
+                    size="compact"
+                    languageOverride="fr"
+                  />
+                </div>
+              )}
             </form>
           </Form>
 

docs/SECURITE_ANTI_ABUS.md

@@ -0,0 +1,196 @@
+# Sécurité anti-abus — La Voix du Peuple
+
+> Document technique décrivant les protections contre les attaques sybil, les floods de bots et les brigading coordonnés. Mis à jour : mai 2026.
+
+---
+
+## Contexte et risque
+
+La plateforme est conçue sans authentification (choix philosophique préservant l'anonymat). Cette absence rend triviale, sans protection, la manipulation des données par :
+
+- **Sybil attacks** : multiplication des soumissions depuis la même entité
+- **Bot floods** : soumissions automatisées en masse
+- **Brigading coordonné** : campagnes organisées pour inonder la synthèse de contenus orientés
+
+Les protections suivantes traitent ce risque sans remettre en cause l'anonymat des contributeurs légitimes.
+
+---
+
+## Couches de protection (ordre d'application)
+
+### 1. Honeypot anti-bot
+
+**Principe** : un champ de formulaire est présent dans le HTML mais rendu invisible aux utilisateurs réels (`display: none`, `position: absolute`, `aria-hidden="true"`). Les bots qui analysent le DOM et remplissent tous les champs déclenchent le honeypot.
+
+**Comportement** :
+- **Client** : si le champ `_hp` a une valeur lors de la soumission, l'appel API n'est pas effectué. Réponse simulée silencieuse côté JS.
+- **Serveur** : si `_hp` est présent et non vide dans le corps JSON, le serveur retourne un `201` factice sans enregistrer quoi que ce soit (`logger.info("Honeypot déclenché")`).
+
+**Fichiers** : `artifacts/voix-du-peuple/src/pages/home.tsx` · `artifacts/flask-api/app.py`
+
+---
+
+### 2. hCaptcha (stub — activer en production)
+
+**Principe** : widget CAPTCHA humain présenté avant la soumission. hCaptcha est choisi pour :
+- Gratuit (tier communautaire)
+- RGPD-compliant (pas de cookies tiers, données UE)
+- Pas de dépendance à Google
+
+**État actuel** : stub intégré, désactivé par défaut.
+
+**Pour activer** :
+1. Créer un compte sur [hcaptcha.com](https://www.hcaptcha.com/)
+2. Créer un site, récupérer la clé de site et la clé secrète
+3. Configurer les variables d'environnement :
+
+```env
+# Frontend (.env dans artifacts/voix-du-peuple/)
+VITE_HCAPTCHA_SITE_KEY=votre-cle-de-site
+
+# Backend (.env ou variable système)
+HCAPTCHA_SECRET_KEY=votre-cle-secrete
+```
+
+4. Reconstruire le frontend : `pnpm build`
+
+**Comportement quand activé** :
+- Le widget hCaptcha s'affiche dans le formulaire avant le bouton "Contribuer"
+- Le bouton est désactivé tant que le CAPTCHA n'est pas validé
+- Le token est transmis dans l'en-tête `X-HCaptcha-Token`
+- Le backend vérifie le token via l'API hCaptcha (`https://hcaptcha.com/siteverify`)
+- Si la clé secrète n'est pas configurée côté serveur, la vérification est sautée (dégradation gracieuse)
+
+**Fichiers** : `artifacts/voix-du-peuple/src/pages/home.tsx` · `artifacts/flask-api/app.py` (`_verify_hcaptcha()`)
+
+---
+
+### 3. Rate limiting par IP + fingerprint
+
+**Outil** : Flask-Limiter v3 avec stockage Redis (si `REDIS_URL` défini) ou mémoire (dev).
+
+**Seuils par défaut** (configurables via variables d'environnement) :
+
+| Endpoint | Limite par défaut | Variable de contrôle |
+|----------|------------------|----------------------|
+| `POST /api/ideas` | 5/min · **3/heure** | `RATE_LIMIT_CONTRIBUTIONS` |
+| `POST /api/ideas/:id/flag` | 3/min · 10/heure | — |
+| `POST /api/admin/login` | 10/min | — |
+| Toutes routes | 60/heure · 200/jour | — |
+
+**Clé de rate limiting** : priorité au fingerprint FingerprintJS (hashé), sinon IP. Empêche de contourner la limite en changeant d'IP si le fingerprint est reconnu.
+
+**Pour activer Redis** :
+```env
+REDIS_URL=redis://localhost:6379/0
+```
+
+Sans Redis, le rate limiting est en mémoire (reset au redémarrage — suffisant pour une instance unique).
+
+**Fichiers** : `artifacts/flask-api/app.py` (`get_fingerprint_key()`, `RATE_LIMIT_CONTRIBUTIONS`)
+
+---
+
+### 4. Fingerprinting non-PII
+
+**Outil** : `@fingerprintjs/fingerprintjs` v4 (open source, pas de compte requis).
+
+**Principe** : FingerprintJS génère un `visitorId` côté client à partir de caractéristiques du navigateur (User-Agent, timezone, canvas fingerprint, etc.) sans créer de cookie tiers ni stocker de données personnelles.
+
+**Flux** :
+1. À l'initialisation de l'app React (`App.tsx`), FingerprintJS est chargé
+2. Le `visitorId` est stocké en mémoire (non persisté)
+3. Il est envoyé sur chaque requête API dans l'en-tête `X-Visitor-Id`
+4. Le backend le hash en SHA-256 (32 premiers hex) avant tout stockage
+5. Le hash est enregistré en base (`ideas.fingerprint_hash`) pour analyse post-hoc si nécessaire
+
+**Données stockées** : uniquement le hash SHA-256 tronqué — non-réversible, non-PII au sens du RGPD. Aucun cookie, aucun suivi cross-site.
+
+**Fichiers** : `artifacts/voix-du-peuple/src/App.tsx` · `lib/api-client-react/src/custom-fetch.ts` · `artifacts/flask-api/app.py` · `artifacts/flask-api/database.py`
+
+---
+
+### 5. Cooldown par session (cookie httpOnly signé)
+
+**Principe** : après une soumission acceptée, un cookie httpOnly signé HMAC-SHA256 est posé. Toute tentative de soumission avant l'expiration du cooldown est rejetée avec un `429`.
+
+**Durée par défaut** : 3600 secondes (1 heure), configurable :
+```env
+CONTRIBUTION_COOLDOWN_SECONDS=3600
+```
+
+**Signature** : le cookie `_cv` contient `{timestamp}.{signature}` où la signature est `HMAC-SHA256(SECRET_KEY, timestamp_bytes)[:16]`. Impossible de forger sans connaître `SECRET_KEY`.
+
+**Prérequis** :
+```env
+SECRET_KEY=une-longue-chaine-aleatoire-minimum-32-chars
+```
+
+Si `SECRET_KEY` n'est pas défini, le cooldown est désactivé (dégradation gracieuse).
+
+**Limite** : fonctionne pleinement en production (même domaine, Nginx reverse proxy). En développement cross-origin (Vite sur port différent de Flask), le cookie n'est pas envoyé automatiquement par le navigateur (CORS `supports_credentials=False`).
+
+**Fichiers** : `artifacts/flask-api/app.py` (`_sign_cooldown()`, `_verify_cooldown()`)
+
+---
+
+### 6. Détection de flood
+
+**Principe** : compteur en mémoire par IP (et par fingerprint si disponible) sur une fenêtre glissante de 5 minutes. Si le seuil est dépassé, une alerte `WARNING` est émise dans les logs.
+
+**Seuil par défaut** : 10 soumissions en 5 minutes, configurable :
+```env
+FLOOD_THRESHOLD=10
+```
+
+**Ce qui se passe** : l'alerte est loggée mais la soumission n'est pas bloquée (le rate limiter Flask-Limiter s'en charge). L'objectif est d'alerter l'opérateur pour investigation.
+
+**Format de l'alerte** :
+```
+WARNING ALERTE FLOOD — IP: 1.2.3.4 | fingerprint: abc123... | seuil: 10/5min
+```
+
+**Pour aller plus loin** : brancher sur un webhook (email Mailgun/Brevo, Slack/Mattermost) via un hook sur les logs `WARNING` avec le pattern `ALERTE FLOOD`.
+
+**Limite** : l'état est en mémoire et se réinitialise au redémarrage. Pour une persistance cross-restart, utiliser Redis directement avec `EXPIRE`.
+
+**Fichiers** : `artifacts/flask-api/app.py` (`_check_flood()`, `_flood_tracker`)
+
+---
+
+## Variables d'environnement récapitulatif
+
+```env
+# Rate limiting
+REDIS_URL=redis://localhost:6379/0           # Optionnel — sinon mémoire
+RATE_LIMIT_CONTRIBUTIONS=5 per minute;3 per hour  # Format flask-limiter
+
+# Cooldown session
+SECRET_KEY=une-longue-chaine-aleatoire-minimum-32-chars
+CONTRIBUTION_COOLDOWN_SECONDS=3600
+
+# Flood detection
+FLOOD_THRESHOLD=10
+
+# hCaptcha (désactivé si absent)
+HCAPTCHA_SECRET_KEY=votre-cle-secrete        # Backend
+VITE_HCAPTCHA_SITE_KEY=votre-cle-de-site     # Frontend (nécessite rebuild)
+```
+
+---
+
+## Ce que ces protections ne couvrent pas
+
+- **Bots sophistiqués JavaScript-capable** : FingerprintJS peut être contourné par un navigateur headless bien configuré. La combinaison IP + fingerprint + hCaptcha rend l'attaque coûteuse mais pas impossible.
+- **VPN / Tor** : le rate limiting IP peut être contourné. Le fingerprint compense partiellement.
+- **Submissions manuelles coordonnées** (brigading humain) : seul le contenu + la modération IA protège contre ce vecteur.
+- **Cross-origin en dev** : le cookie cooldown ne fonctionne pas en développement (ports différents, CORS sans credentials).
+
+---
+
+## Évolutions futures recommandées
+
+1. **Redis** : déployer Redis et configurer `REDIS_URL` en production pour un rate limiting persistant et cross-process.
+2. **hCaptcha** : activer dès que la plateforme est ouverte au public (clé gratuite, 5 minutes de setup).
+3. **Alerte flood automatique** : brancher un webhook Brevo/Mailgun sur les logs `ALERTE FLOOD`.
+4. **CAPTCHA invisible** : envisager hCaptcha en mode "invisible" (score-based) pour ne pas imposer de défi aux utilisateurs légitimes.

lib/api-client-react/src/custom-fetch.ts

@@ -18,6 +18,35 @@ const DEFAULT_JSON_ACCEPT = "application/json, application/problem+json";
 let _baseUrl: string | null = null;
 let _authTokenGetter: AuthTokenGetter | null = null;
 
+// Identifiant de visite non-PII issu de FingerprintJS (hash côté serveur)
+let _visitorId: string | null = null;
+
+// En-têtes supplémentaires par requête (ex. token hCaptcha)
+const _extraHeaders: Record<string, string> = {};
+
+/**
+ * Enregistre l'identifiant de visite FingerprintJS.
+ * Envoyé automatiquement comme en-tête X-Visitor-Id sur chaque requête.
+ */
+export function setVisitorId(id: string): void {
+  _visitorId = id;
+}
+
+/**
+ * Ajoute ou met à jour un en-tête supplémentaire pour les prochaines requêtes.
+ * Utiliser pour passer des tokens à usage unique (ex. hCaptcha).
+ */
+export function addExtraHeader(key: string, value: string): void {
+  _extraHeaders[key] = value;
+}
+
+/**
+ * Supprime un en-tête supplémentaire.
+ */
+export function removeExtraHeader(key: string): void {
+  delete _extraHeaders[key];
+}
+
 /**
  * Set a base URL that is prepended to every relative request URL
  * (i.e. paths that start with `/`).
@@ -358,6 +387,18 @@ export async function customFetch<T = unknown>(
     }
   }
 
+  // En-tête fingerprint non-PII (FingerprintJS)
+  if (_visitorId && !headers.has("x-visitor-id")) {
+    headers.set("x-visitor-id", _visitorId);
+  }
+
+  // En-têtes supplémentaires (ex. token hCaptcha)
+  for (const [key, value] of Object.entries(_extraHeaders)) {
+    if (value && !headers.has(key)) {
+      headers.set(key, value);
+    }
+  }
+
   const requestInfo = { method, url: resolveUrl(input) };
 
   const response = await fetch(input, { ...init, method, headers });

lib/api-client-react/src/index.ts

@@ -1,4 +1,10 @@
 export * from "./generated/api";
 export * from "./generated/api.schemas";
-export { setBaseUrl, setAuthTokenGetter } from "./custom-fetch";
+export {
+  setBaseUrl,
+  setAuthTokenGetter,
+  setVisitorId,
+  addExtraHeader,
+  removeExtraHeader,
+} from "./custom-fetch";
 export type { AuthTokenGetter } from "./custom-fetch";