Initial commit

backend/app/core/security.py

@@ -0,0 +1,83 @@
+from datetime import datetime, timedelta
+from typing import Optional
+from jose import JWTError, jwt
+from pydantic import BaseModel
+from fastapi import Depends, HTTPException, status
+from fastapi.security import HTTPBearer, HTTPAuthorizationCredentials
+import pam
+from app.core.config import settings
+
+
+class TokenData(BaseModel):
+    username: str
+    exp: datetime
+
+
+class Token(BaseModel):
+    access_token: str
+    token_type: str
+    username: str
+
+
+class User(BaseModel):
+    username: str
+    is_authenticated: bool = True
+
+
+def authenticate_user(username: str, password: str) -> Optional[User]:
+    """
+    Authentifie un utilisateur via PAM (Pluggable Authentication Module)
+    Validé contre le système Debian/Linux
+    """
+    try:
+        pam_auth = pam.pam()
+        if pam_auth.authenticate(username, password):
+            return User(username=username)
+        return None
+    except Exception as e:
+        print(f"Erreur PAM: {e}")
+        return None
+
+
+def create_access_token(username: str, expires_delta: Optional[timedelta] = None) -> str:
+    """Crée un token JWT"""
+    if expires_delta:
+        expire = datetime.utcnow() + expires_delta
+    else:
+        expire = datetime.utcnow() + timedelta(
+            minutes=settings.ACCESS_TOKEN_EXPIRE_MINUTES
+        )
+    
+    to_encode = {"sub": username, "exp": expire}
+    encoded_jwt = jwt.encode(
+        to_encode, settings.SECRET_KEY, algorithm=settings.ALGORITHM
+    )
+    return encoded_jwt
+
+
+security = HTTPBearer()
+
+
+async def get_current_user(credentials: HTTPAuthorizationCredentials = Depends(security)) -> User:
+    """
+    Valide le token JWT et retourne l'utilisateur actuel
+    """
+    credential_exception = HTTPException(
+        status_code=status.HTTP_401_UNAUTHORIZED,
+        detail="Impossible de valider les credentials",
+        headers={"WWW-Authenticate": "Bearer"},
+    )
+    
+    try:
+        token = credentials.credentials
+        payload = jwt.decode(
+            token, settings.SECRET_KEY, algorithms=[settings.ALGORITHM]
+        )
+        username: str = payload.get("sub")
+        if username is None:
+            raise credential_exception
+        token_data = TokenData(username=username, exp=payload.get("exp"))
+    except JWTError:
+        raise credential_exception
+    
+    return User(username=token_data.username)