05/18 Enhanced codes and functionalities 3

app/routes/auth.py

@@ -922,8 +922,11 @@ def recovery_items():
     the client must derive it by decrypting the recovery blob with the recovery
     code. This ensures only the holder of the recovery code can compute the proof.
 
-    The challenge row is NOT consumed here — it is consumed by the final
-    POST /recover call so that endpoint can also validate the proof.
+    Replay prevention: the challenge is consumed (deleted) on success, then
+    immediately re-issued with the same expected_proof but a new nonce and a
+    fresh TTL.  This means each call to /recovery/items rotates the challenge,
+    so a captured X-Recovery-Proof header cannot be replayed by a third party.
+    POST /recover will consume the rotated challenge on final commit.
     Items are returned as encrypted ciphertext blobs only.
     """
     from app.models.recovery_challenge import RecoveryChallenge
@@ -938,11 +941,9 @@ def recovery_items():
     if not user or not user.recovery_enc_salt:
         return jsonify({'error': 'No recovery data found'}), 404
 
-    # Validate against the DB-stored challenge without consuming it —
-    # POST /recover will consume it atomically on commit.
-    challenge = RecoveryChallenge.query.filter_by(user_id=user.id).first()
-    from datetime import datetime, timezone
-    if not challenge or challenge.expires_at < datetime.now(timezone.utc).replace(tzinfo=None):
+    # Consume the current challenge atomically.
+    challenge = RecoveryChallenge.consume(user.id)
+    if not challenge:
         return jsonify({'error': 'No active recovery challenge. Call /recovery/data first.'}), 400
 
     if not verify_recovery_proof(challenge.expected_proof, client_proof):
@@ -957,6 +958,17 @@ def recovery_items():
         db.session.commit()
         return jsonify({'error': 'Invalid recovery proof'}), 401
 
+    # Re-issue a fresh challenge with the same expected_proof but a new nonce
+    # and TTL. POST /recover will consume this rotated challenge on final commit.
+    # The client continues to send the same proof value — no client change needed.
+    new_nonce = generate_recovery_nonce()
+    RecoveryChallenge.create(
+        user_id=user.id,
+        nonce=new_nonce,
+        expected_proof=challenge.expected_proof,  # same proof, new nonce
+    )
+    db.session.commit()
+
     from app.models.vault_item import VaultItem
     items = VaultItem.query.filter_by(user_id=user.id).all()
     return jsonify({

app/static/js/vault.js

@@ -130,9 +130,11 @@ const Vault = (() => {
       res = await fetch(path, merged);
     }
 
-    if (!res.ok && res.status !== 404) {
+    if (!res.ok) {
       const err = await res.json().catch(() => ({}));
-      throw new Error(err.error || `HTTP ${res.status}`);
+      const e = new Error(err.error || `HTTP ${res.status}`);
+      e.status = res.status;
+      throw e;
     }
     return res;
   }
@@ -974,7 +976,35 @@ const Vault = (() => {
 
   let _importViewInitialised = false;
 
+  function _resetImportView() {
+    _importRows = [];
+    const fileInput = document.getElementById("import-file-input");
+    const fileNameEl = document.getElementById("import-file-name");
+    const previewEl = document.getElementById("import-preview");
+    const confirmBtn = document.getElementById("btn-import-confirm");
+    const resultEl = document.getElementById("import-result");
+    if (fileInput) fileInput.value = "";
+    if (fileNameEl) fileNameEl.textContent = "No file chosen";
+    if (previewEl) {
+      previewEl.innerHTML = "";
+      previewEl.classList.add("hidden");
+    }
+    if (confirmBtn) {
+      confirmBtn.disabled = true;
+      confirmBtn.textContent = "Import items";
+      delete confirmBtn.dataset.mode;
+    }
+    if (resultEl) {
+      resultEl.innerHTML = "";
+      resultEl.classList.add("hidden");
+    }
+  }
+
   function loadImportExportView() {
+    // Reset import panel state every time the view is entered so a previous
+    // import result or file preview is never shown stale on re-entry.
+    _resetImportView();
+
     if (_importViewInitialised) return;
     _importViewInitialised = true;
 
@@ -1238,7 +1268,6 @@ const Vault = (() => {
         });
         if (!res) return;
         const data = await res.json();
-        if (!res.ok) throw new Error(data.error || "Import failed.");
 
         resultEl.innerHTML = `✅ Imported <strong>${data.imported}</strong> item(s)${data.skipped ? `, skipped ${data.skipped} malformed row(s)` : ""}.`;
         resultEl.className = "import-result import-result-ok";