Cleanup bunch of blinding APIs

Now the blinding APIs are separated into smaller chunks. This allows
1) Blinding only the values or the assets but not both
2) Not relying on rng to set asset/value blinding factors
3) Bunch of API cleanups with better input parameters

Author: sanket1729

examples/pset_blind_coinjoin.rs

@@ -262,20 +262,16 @@ fn main() {
     // ----------------------------------------------------------
     // B Adds it's own outputs. Step 2 completed
     // ----- Step 3: B to blind it's own outputs
-    let inp_txout_sec = [
-        None,
-        Some(&asset_txout_secrets.sec),
-    ];
+    let mut inp_txout_sec = HashMap::new();
+    inp_txout_sec.insert(1, asset_txout_secrets.sec);
 
     pset.blind_non_last(&mut rng, &secp, &inp_txout_sec).unwrap();
     assert_eq!(pset, deser_pset(&tests["pset_coinjoined_B_blinded"]));
 
     // Step 4: A blinds it's own inputs
-    let inp_txout_sec = [
-        Some(&btc_txout_secrets.sec),
-        None,
-    ];
-    pset.blind_last(&mut rng, &secp, &inp_txout_sec).unwrap();
+    let mut inp_txout_sec_a = HashMap::new();
+    inp_txout_sec_a.insert(0, btc_txout_secrets.sec);
+    pset.blind_last(&mut rng, &secp, &inp_txout_sec_a).unwrap();
     assert_eq!(pset, deser_pset(&tests["pset_coinjoined_blinded"]));
 
     // check whether the blinding was correct

examples/raw_blind.rs

@@ -10,7 +10,7 @@ use elements::{
     bitcoin::PublicKey, pset::PartiallySignedTransaction as Pset, Address, AddressParams, OutPoint,
     Script, TxOutSecrets, TxOutWitness, Txid, WScriptHash,
 };
-use elements::{pset, secp256k1_zkp};
+use elements::{pset, secp256k1_zkp, SurjectionInput};
 
 use elements::encode::{deserialize, serialize_hex};
 use elements::hashes::hex::FromHex;
@@ -164,8 +164,8 @@ fn main() {
     // Add outputs
     // Send 5_000 worth of asset units to new address
     let inputs = [
-        (btc_txout.asset, Some(&btc_txout_secrets.sec)),
-        (asset_txout.asset, Some(&asset_txout_secrets.sec)),
+        (SurjectionInput::from_txout_secrets(btc_txout_secrets.sec)),
+        (SurjectionInput::from_txout_secrets(asset_txout_secrets.sec)),
     ];
 
     let dest_wsh =
@@ -175,7 +175,7 @@ fn main() {
     let dest_blind_pk =
         PublicKey::from_str("0212bf0ea45b733dfde8ecb5e896306c4165c666c99fc5d1ab887f71393a975cea")
             .unwrap();
-    let (dest_asset_txout, dest_abf, dest_vbf) = TxOut::new_not_last_confidential(
+    let (dest_asset_txout, dest_abf, dest_vbf, _) = TxOut::new_not_last_confidential(
         &mut rng,
         &secp,
         dest_amt,
@@ -196,7 +196,7 @@ fn main() {
     let change_wsh =
         WScriptHash::from_str("f6b43d56e004e9d0b1ec2fc3c95511d81af08420992be8dec7f86cdf8970b3e2")
             .unwrap();
-    let (change_asset_txout, asset_change_abf, asset_change_vbf) =
+    let (change_asset_txout, asset_change_abf, asset_change_vbf, _) =
         TxOut::new_not_last_confidential(
             &mut rng,
             &secp,
@@ -250,19 +250,16 @@ fn main() {
 
     // For the last output we require all secrets.
     let inputs = [
-        (btc_txout.asset, &btc_txout_secrets.sec),
-        (asset_txout.asset, &asset_txout_secrets.sec),
+        btc_txout_secrets.sec,
+        asset_txout_secrets.sec,
     ];
-    let (btc_change_txout, _abf, _vbf) = TxOut::new_last_confidential(
+    let (btc_change_txout, _abf, _vbf, _) = TxOut::new_last_confidential(
         &mut rng,
         &secp,
         change_amt,
-        Address::p2wsh(
-            &Script::new_v0_wsh(&change_wsh),
-            Some(change_blind_pk.inner),
-            &PARAMS,
-        ),
         btc_txout_secrets.sec.asset,
+        Script::new_v0_wsh(&change_wsh),
+        change_blind_pk.inner,
         &inputs,
         &output_secrets,
     )