Adding a shielding fee for normal shielding txs.

crates/sdk/src/tx.rs

@@ -2747,15 +2747,9 @@ pub async fn build_ibc_transfer(
         Some(source.clone()),
         Some(source.clone()),
         vec![],
-        if let Some(IbcShieldingData {
-            shielding_fee_payer: payer,
-            ..
-        }) = &args.ibc_shielding_data
-        {
-            Some(payer.clone())
-        } else {
-            None
-        },
+        args.ibc_shielding_data
+            .as_ref()
+            .map(|shielding_data| shielding_data.shielding_fee_payer.clone()),
         args.source.spending_key().is_some(),
         vec![],
         None,

crates/shielded_token/src/vp.rs

@@ -624,20 +624,31 @@ where
                 return Err(error);
             }
         }
+        let masp_tx_id = shielded_tx.txid().into();
+        let has_trans_inputs = shielded_tx
+            .transparent_bundle()
+            .map(|b| !b.vin.empty())
+            .unwrap_or(false);
         // The transaction shall not push masp authorizer actions that are not
         // needed because this might lead vps to run a wrong validation logic
         if !actions_authorizers.is_empty()
-            && shielded_tx
-                .transparent_bundle()
-                .map(|b| b.vin.is_empty())
-                .unwrap_or(true)
+            && !has_trans_inputs
         {
             let error = Error::new_const(
                 "Found masp authorizer actions that are not required",
             );
             tracing::debug!("{error}");
             return Err(error);
         }
+        // check that the tx has a shielding fee section
+        if has_trans_inputs && batched_tx.tx.get_shielding_fee_section(&masp_tx_id).is_none()
+        {
+            let error = Error::new_const(
+                "Found a shielding transaction with a shielding fee section",
+            );
+            tracing::debug!("{error}");
+            return Err(error);
+        }
 
         // Verify the proofs
         verify_shielded_tx(&shielded_tx, |gas| ctx.charge_gas(gas))