dao-exec: input value blind should be the sum of blinds used for input value commits

bin/drk/src/rpc_dao.rs

@@ -406,7 +406,6 @@ impl Drk {
         let user_coin_blind = pallas::Base::random(&mut OsRng);
         let dao_serial = pallas::Base::random(&mut OsRng);
         let dao_coin_blind = pallas::Base::random(&mut OsRng);
-        let input_value_blind = pallas::Scalar::random(&mut OsRng);
 
         // TODO: FIXME: Clean this up and create an API
         let exec_signature_secret = SecretKey::random(&mut OsRng);
@@ -414,7 +413,6 @@ impl Drk {
         let mut xfer_inputs = vec![];
 
         let mut input_coins = vec![];
-        let mut input_value_blinds = vec![];
         let mut input_amount = 0;
         for coin in coins {
             input_amount += coin.note.value;
@@ -427,6 +425,7 @@ impl Drk {
         let money_merkle_tree = self.get_money_tree().await?;
         let money_merkle_root = money_merkle_tree.root(0).unwrap();
 
+        let mut input_value_blind = pallas::Scalar::from(0);
         for coin in &input_coins {
             let value_blind = pallas::Scalar::random(&mut OsRng);
             let sig_secret = SecretKey::random(&mut OsRng);
@@ -444,7 +443,7 @@ impl Drk {
                 signature_secret: sig_secret,
             });
 
-            input_value_blinds.push(value_blind);
+            input_value_blind += value_blind;
         }
 
         let input_sum = input_coins.iter().map(|x| x.note.value).sum::<u64>();