Rewrite server: FastAPI + auth (users/roles/tokens) + admin WebUI + server-authoritative covers/metadata

server/security.py

@@ -0,0 +1,138 @@
+"""Password hashing, API/session tokens, and FastAPI auth dependencies.
+
+Stdlib-only crypto: PBKDF2-SHA256 for passwords, SHA-256 hashed bearer tokens
+for both the desktop client (kind="api") and the WebUI session (kind="session").
+"""
+import hashlib
+import secrets
+from datetime import datetime, timezone
+
+from fastapi import Depends, Header, HTTPException, Request, status
+
+from app.db import get_connection
+
+_PBKDF2_ITERATIONS = 600_000
+
+ADMIN_ROLE = "admin"
+EDITOR_ROLE = "editor"
+USER_ROLE = "user"
+ROLES = (ADMIN_ROLE, EDITOR_ROLE, USER_ROLE)
+
+
+def now_iso():
+    return datetime.now(timezone.utc).isoformat(timespec="seconds")
+
+
+def hash_password(password: str) -> str:
+    salt = secrets.token_bytes(16)
+    digest = hashlib.pbkdf2_hmac("sha256", password.encode("utf-8"), salt, _PBKDF2_ITERATIONS)
+    return f"pbkdf2_sha256${_PBKDF2_ITERATIONS}${salt.hex()}${digest.hex()}"
+
+
+def verify_password(password: str, stored: str) -> bool:
+    try:
+        scheme, iterations, salt_hex, digest_hex = stored.split("$")
+        if scheme != "pbkdf2_sha256":
+            return False
+        salt = bytes.fromhex(salt_hex)
+        expected = bytes.fromhex(digest_hex)
+        actual = hashlib.pbkdf2_hmac("sha256", password.encode("utf-8"), salt, int(iterations))
+        return secrets.compare_digest(actual, expected)
+    except (ValueError, TypeError):
+        return False
+
+
+def _hash_token(raw: str) -> str:
+    return hashlib.sha256(raw.encode("utf-8")).hexdigest()
+
+
+def issue_token(user_id: int, kind: str = "api", label: str = "", expires_at: str = "") -> str:
+    """Create a token row and return the raw token (only shown once)."""
+    raw = secrets.token_urlsafe(32)
+    conn = get_connection()
+    try:
+        conn.execute(
+            "INSERT INTO api_tokens (user_id, token_hash, label, kind, created_at, last_used_at, expires_at, revoked_at) "
+            "VALUES (?, ?, ?, ?, ?, ?, ?, NULL)",
+            (user_id, _hash_token(raw), label, kind, now_iso(), now_iso(), expires_at or None),
+        )
+        conn.commit()
+    finally:
+        conn.close()
+    return raw
+
+
+def revoke_token(raw: str) -> None:
+    conn = get_connection()
+    try:
+        conn.execute(
+            "UPDATE api_tokens SET revoked_at = ? WHERE token_hash = ?",
+            (now_iso(), _hash_token(raw)),
+        )
+        conn.commit()
+    finally:
+        conn.close()
+
+
+def get_user_by_token(raw: str):
+    if not raw:
+        return None
+    conn = get_connection()
+    try:
+        row = conn.execute(
+            "SELECT u.id, u.username, u.role, u.is_active FROM api_tokens t "
+            "JOIN users u ON u.id = t.user_id "
+            "WHERE t.token_hash = ? AND t.revoked_at IS NULL "
+            "AND (t.expires_at IS NULL OR t.expires_at = '' OR t.expires_at > ?)",
+            (_hash_token(raw), now_iso()),
+        ).fetchone()
+        if row is None or not row["is_active"]:
+            return None
+        conn.execute(
+            "UPDATE api_tokens SET last_used_at = ? WHERE token_hash = ?",
+            (now_iso(), _hash_token(raw)),
+        )
+        conn.commit()
+        return dict(row)
+    finally:
+        conn.close()
+
+
+def get_current_user(request: Request, authorization: str = Header(default="")):
+    """Authenticate via ``Authorization: Bearer`` (client) or session cookie (WebUI)."""
+    token = ""
+    if authorization.startswith("Bearer "):
+        token = authorization[7:].strip()
+    else:
+        token = request.cookies.get("psppt_session", "")
+    user = get_user_by_token(token)
+    if user is None:
+        raise HTTPException(status_code=status.HTTP_401_UNAUTHORIZED, detail="Not authenticated")
+    return user
+
+
+def require_role(*roles):
+    """Dependency factory: only users with one of ``roles`` may pass."""
+    def dependency(user=Depends(get_current_user)):
+        if user["role"] not in roles:
+            raise HTTPException(status_code=status.HTTP_403_FORBIDDEN, detail="Insufficient permissions")
+        return user
+    return dependency
+
+
+def ensure_admin(username: str, password: str) -> bool:
+    """Create the initial admin account when the users table is empty."""
+    conn = get_connection()
+    try:
+        count = conn.execute("SELECT COUNT(*) AS n FROM users").fetchone()["n"]
+        if count == 0:
+            conn.execute(
+                "INSERT INTO users (username, password_hash, role, is_active, created_at) "
+                "VALUES (?, ?, 'admin', 1, ?)",
+                (username, hash_password(password), now_iso()),
+            )
+            conn.commit()
+            return True
+    finally:
+        conn.close()
+    return False