Get tests passing for nested segwit

- change commit_witness_inputs inputs param to (psbt::Input, TxIn)
- update integration tests to use nested segwit addresses
- fallback to psbtin.redeem_script if psbtin.final_script_sig is None
- don't clear sender signatures until after apply_fee
- update unit tests for nested segwit PSBTs

payjoin-cli/src/app/mod.rs

@@ -120,3 +120,23 @@ fn read_local_cert() -> Result<Vec<u8>> {
     local_cert_path.push(LOCAL_CERT_FILE);
     Ok(std::fs::read(local_cert_path)?)
 }
+
+pub fn input_pair_from_list_unspent(
+    utxo: &bitcoincore_rpc::bitcoincore_rpc_json::ListUnspentResultEntry,
+) -> (bitcoin::psbt::Input, bitcoin::TxIn) {
+    let psbtin = bitcoin::psbt::Input {
+        // TODO: non_witness_utxo for legacy support
+        witness_utxo: Some(bitcoin::TxOut {
+            value: utxo.amount,
+            script_pubkey: utxo.script_pub_key.clone(),
+        }),
+        redeem_script: utxo.redeem_script.clone(),
+        witness_script: utxo.witness_script.clone(),
+        ..Default::default()
+    };
+    let txin = bitcoin::TxIn {
+        previous_output: bitcoin::OutPoint { txid: utxo.txid, vout: utxo.vout },
+        ..Default::default()
+    };
+    (psbtin, txin)
+}

payjoin-cli/src/app/v1.rs

@@ -21,7 +21,7 @@ use tokio::net::TcpListener;
 
 use super::config::AppConfig;
 use super::App as AppTrait;
-use crate::app::http_agent;
+use crate::app::{http_agent, input_pair_from_list_unspent};
 use crate::db::Database;
 #[cfg(feature = "danger-local-https")]
 pub const LOCAL_CERT_FILE: &str = "localhost.der";
@@ -396,13 +396,10 @@ fn try_contributing_inputs(
         .find(|i| i.txid == selected_outpoint.txid && i.vout == selected_outpoint.vout)
         .context("This shouldn't happen. Failed to retrieve the privacy preserving utxo from those we provided to the seclector.")?;
     log::debug!("selected utxo: {:#?}", selected_utxo);
-    let txo_to_contribute = bitcoin::TxOut {
-        value: selected_utxo.amount,
-        script_pubkey: selected_utxo.script_pub_key.clone(),
-    };
+    let input_pair = input_pair_from_list_unspent(selected_utxo);
 
     Ok(payjoin
-        .contribute_witness_inputs(vec![(selected_outpoint, txo_to_contribute)])
+        .contribute_witness_inputs(vec![input_pair])
         .expect("This shouldn't happen. Failed to contribute inputs.")
         .commit_inputs())
 }

payjoin-cli/src/app/v2.rs

@@ -375,13 +375,10 @@ fn try_contributing_inputs(
         .find(|i| i.txid == selected_outpoint.txid && i.vout == selected_outpoint.vout)
         .context("This shouldn't happen. Failed to retrieve the privacy preserving utxo from those we provided to the seclector.")?;
     log::debug!("selected utxo: {:#?}", selected_utxo);
-    let txo_to_contribute = bitcoin::TxOut {
-        value: selected_utxo.amount,
-        script_pubkey: selected_utxo.script_pub_key.clone(),
-    };
+    let input_pair = input_pair_from_list_unspent(selected_utxo);
 
     Ok(payjoin
-        .contribute_witness_inputs(vec![(selected_outpoint, txo_to_contribute)])
+        .contribute_witness_inputs(vec![input_pair])
         .expect("This shouldn't happen. Failed to contribute inputs.")
         .commit_inputs())
 }

payjoin/src/psbt.rs

@@ -195,17 +195,24 @@ impl<'a> InputPair<'a> {
         // Get the input weight prediction corresponding to spending an output of this address type
         let iwp = match self.address_type()? {
             P2pkh => Ok(InputWeightPrediction::P2PKH_COMPRESSED_MAX),
-            P2sh =>
-                match self.psbtin.final_script_sig.as_ref().and_then(|s| redeem_script(s.as_ref()))
-                {
+            P2sh => {
+                let redeem_script = if let Some(ref script_sig) = self.psbtin.final_script_sig {
+                    redeem_script(script_sig.as_ref())
+                } else if let Some(ref script) = self.psbtin.redeem_script {
+                    Some(script.as_ref())
+                } else {
+                    None
+                };
+                match redeem_script {
                     // Nested segwit p2wpkh.
                     Some(script) if script.is_witness_program() && script.is_p2wpkh() =>
                         Ok(NESTED_P2WPKH_MAX),
                     // Other script or witness program.
                     Some(_) => Err(InputWeightError::NotSupported),
                     // No redeem script provided. Cannot determine the script type.
                     None => Err(InputWeightError::NotFinalized),
-                },
+                }
+            }
             P2wpkh => Ok(InputWeightPrediction::P2WPKH_MAX),
             P2wsh => Err(InputWeightError::NotSupported),
             P2tr => Ok(InputWeightPrediction::P2TR_KEY_DEFAULT_SIGHASH),

payjoin/src/receive/mod.rs

@@ -45,7 +45,7 @@ use error::{
 };
 use optional_parameters::Params;
 
-use crate::psbt::PsbtExt;
+use crate::psbt::{InputPair, PsbtExt};
 
 pub trait Headers {
     fn get_header(&self, key: &str) -> Option<&str>;
@@ -577,7 +577,7 @@ impl WantsInputs {
     /// Any excess input amount is added to the change_vout output indicated previously.
     pub fn contribute_witness_inputs(
         self,
-        inputs: impl IntoIterator<Item = (OutPoint, TxOut)>,
+        inputs: impl IntoIterator<Item = (bitcoin::psbt::Input, bitcoin::TxIn)>,
     ) -> Result<WantsInputs, InputContributionError> {
         let mut payjoin_psbt = self.payjoin_psbt.clone();
         // The payjoin proposal must not introduce mixed input sequence numbers
@@ -592,21 +592,15 @@ impl WantsInputs {
         // Insert contributions at random indices for privacy
         let mut rng = rand::thread_rng();
         let mut receiver_input_amount = Amount::ZERO;
-        for (outpoint, txo) in inputs.into_iter() {
-            receiver_input_amount += txo.value;
+        for (psbtin, txin) in inputs.into_iter() {
+            receiver_input_amount +=
+                InputPair { txin: &txin, psbtin: &psbtin }.previous_txout().expect("txout").value;
             let index = rng.gen_range(0..=self.payjoin_psbt.unsigned_tx.input.len());
-            payjoin_psbt.inputs.insert(
-                index,
-                bitcoin::psbt::Input { witness_utxo: Some(txo), ..Default::default() },
-            );
-            payjoin_psbt.unsigned_tx.input.insert(
-                index,
-                bitcoin::TxIn {
-                    previous_output: outpoint,
-                    sequence: original_sequence,
-                    ..Default::default()
-                },
-            );
+            payjoin_psbt.inputs.insert(index, psbtin);
+            payjoin_psbt
+                .unsigned_tx
+                .input
+                .insert(index, bitcoin::TxIn { sequence: original_sequence, ..txin });
         }
 
         // Add the receiver change amount to the receiver change output, if applicable
@@ -838,14 +832,14 @@ impl ProvisionalProposal {
         min_feerate_sat_per_vb: Option<FeeRate>,
         max_feerate_sat_per_vb: FeeRate,
     ) -> Result<PayjoinProposal, Error> {
-        for i in self.sender_input_indexes() {
+        let mut psbt = self.apply_fee(min_feerate_sat_per_vb, max_feerate_sat_per_vb)?.clone();
+        for i in 0..psbt.inputs.len() {
             log::trace!("Clearing sender script signatures for input {}", i);
-            self.payjoin_psbt.inputs[i].final_script_sig = None;
-            self.payjoin_psbt.inputs[i].final_script_witness = None;
-            self.payjoin_psbt.inputs[i].tap_key_sig = None;
+            psbt.inputs[i].final_script_sig = None;
+            psbt.inputs[i].final_script_witness = None;
+            psbt.inputs[i].tap_key_sig = None;
         }
-        let psbt = self.apply_fee(min_feerate_sat_per_vb, max_feerate_sat_per_vb)?;
-        let psbt = wallet_process_psbt(psbt)?;
+        let psbt = wallet_process_psbt(&psbt)?;
         let payjoin_proposal = self.prepare_psbt(psbt)?;
         Ok(payjoin_proposal)
     }
@@ -874,6 +868,7 @@ impl PayjoinProposal {
 mod test {
     use std::str::FromStr;
 
+    use bitcoin::hashes::serde::Deserialize;
     use bitcoin::hashes::Hash;
     use bitcoin::{Address, Network, ScriptBuf};
     use rand::rngs::StdRng;
@@ -958,23 +953,9 @@ mod test {
         // Specify excessive fee rate in sender params
         proposal.params.min_feerate = FeeRate::from_sat_per_vb_unchecked(1000);
         // Input contribution for the receiver, from the BIP78 test vector
-        let input: (OutPoint, TxOut) = (
-            OutPoint {
-                txid: "833b085de288cda6ff614c6e8655f61e7ae4f84604a2751998dc25a0d1ba278f"
-                    .parse()
-                    .unwrap(),
-                vout: 1,
-            },
-            TxOut {
-                value: Amount::from_sat(2000000),
-                // HACK: The script pubkey in the original test vector is a nested p2sh witness
-                // script, which is not correctly supported in our current weight calculations.
-                // To get around this limitation, this test uses a native segwit script instead.
-                script_pubkey: ScriptBuf::new_p2wpkh(&bitcoin::WPubkeyHash::hash(
-                    "00145f806655e5924c9204c2d51be5394f4bf9eda210".as_bytes(),
-                )),
-            },
-        );
+        let proposal_psbt = Psbt::from_str("cHNidP8BAJwCAAAAAo8nutGgJdyYGXWiBEb45Hoe9lWGbkxh/6bNiOJdCDuDAAAAAAD+////jye60aAl3JgZdaIERvjkeh72VYZuTGH/ps2I4l0IO4MBAAAAAP7///8CJpW4BQAAAAAXqRQd6EnwadJ0FQ46/q6NcutaawlEMIcACT0AAAAAABepFHdAltvPSGdDwi9DR+m0af6+i2d6h9MAAAAAAAEBIICEHgAAAAAAF6kUyPLL+cphRyyI5GTUazV0hF2R2NWHAQcXFgAUX4BmVeWSTJIEwtUb5TlPS/ntohABCGsCRzBEAiBnu3tA3yWlT0WBClsXXS9j69Bt+waCs9JcjWtNjtv7VgIge2VYAaBeLPDB6HGFlpqOENXMldsJezF9Gs5amvDQRDQBIQJl1jz1tBt8hNx2owTm+4Du4isx0pmdKNMNIjjaMHFfrQAAAA==").unwrap();
+        let input: (bitcoin::psbt::Input, bitcoin::TxIn) =
+            (proposal_psbt.inputs[1].clone(), proposal_psbt.unsigned_tx.input[1].clone());
         let mut payjoin = proposal
             .assume_interactive_receiver()
             .check_inputs_not_owned(|_| Ok(false))
@@ -1021,13 +1002,18 @@ mod test {
 
         // Input weight for a single nested P2WPKH (nested segwit) receiver input
         let nested_p2wpkh_proposal = ProvisionalProposal {
-            original_psbt: Psbt::from_str("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").unwrap(),
-            payjoin_psbt: Psbt::from_str("cHNidP8BAJoCAAAAAn57euL5j6xOst5JB/e/gp58RihmmpxXpsc2hEKKcVFkAAAAAAD9////VinByqmVDo3wPNB9LnNELJoJ0g+hOdWiTSXzWEUVtiAAAAAAAP3///8CEBkGKgEAAAAWABSZUDn7eqenP01ziWRBnTCrpwwD6vHQApUAAAAAFgAUvrGHqCNIebOcmc8xuiUbvBsa7C0AAAAAAAEAhgIAAAABAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAD/////BAKqAAD/////AgD5ApUAAAAAF6kU7J597iCNejMvinOLm9w+uMx4InCHAAAAAAAAAAAmaiSqIant4vYcP3HR3v0/qZnfo2lTdVxpBol5mWK0i+vYNpdOjPkAAAAAAQEgAPkClQAAAAAXqRTsnn3uII16My+Kc4ub3D64zHgicIcAAQCEAgAAAAEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAP////8CYAD/////AgDyBSoBAAAAF6kUx/+ZHBBBZ+6E/US1N2Oe7IDItXiHAAAAAAAAAAAmaiSqIant4vYcP3HR3v0/qZnfo2lTdVxpBol5mWK0i+vYNpdOjPkAAAAAAQEgAPIFKgEAAAAXqRTH/5kcEEFn7oT9RLU3Y57sgMi1eIcBBxcWABRDVkPBhZHK7tVQqp2uWqQC/GGTCgEIawJHMEQCIEv8/8VpUz0dK4MCcVzS7zoyt+hPRvWwLskZBuaurnFiAiBIuyt1IRaHqFSspDbjDNM607nrDQz4lmDnekNqMNn07AEhAp1Ol7vKvG2Oi8RSrsb7uSPTET83/YXuknx63PhfCG/zAAAA").unwrap(),
+            original_psbt: Psbt::from_str("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").unwrap(),
+            payjoin_psbt: Psbt::from_str("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").unwrap(),
             params: Params::default(),
             change_vout: 0
         };
         // Currently nested segwit is not supported, see https://github.com/payjoin/rust-payjoin/issues/358
-        assert!(nested_p2wpkh_proposal.additional_input_weight().is_err());
+        assert_eq!(
+            nested_p2wpkh_proposal
+                .additional_input_weight()
+                .expect("should calculate input weight"),
+            Weight::from_wu(364)
+        );
 
         // Input weight for a single P2WPKH (native segwit) receiver input
         let p2wpkh_proposal = ProvisionalProposal {

payjoin/src/receive/v2/mod.rs

@@ -468,7 +468,7 @@ impl WantsInputs {
     /// Any excess input amount is added to the change_vout output indicated previously.
     pub fn contribute_witness_inputs(
         self,
-        inputs: impl IntoIterator<Item = (OutPoint, TxOut)>,
+        inputs: impl IntoIterator<Item = (bitcoin::psbt::Input, bitcoin::TxIn)>,
     ) -> Result<WantsInputs, InputContributionError> {
         let inner = self.inner.contribute_witness_inputs(inputs)?;
         Ok(WantsInputs { inner, context: self.context })

payjoin/tests/integration.rs

@@ -639,15 +639,10 @@ mod integration {
                 .iter()
                 .find(|i| i.txid == selected_outpoint.txid && i.vout == selected_outpoint.vout)
                 .unwrap();
-            let txo_to_contribute = bitcoin::TxOut {
-                value: selected_utxo.amount,
-                script_pubkey: selected_utxo.script_pub_key.clone(),
-            };
+            let input_pair = input_pair_from_list_unspent(selected_utxo);
 
-            let payjoin = payjoin
-                .contribute_witness_inputs(vec![(selected_outpoint, txo_to_contribute)])
-                .unwrap()
-                .commit_inputs();
+            let payjoin =
+                payjoin.contribute_witness_inputs(vec![input_pair]).unwrap().commit_inputs();
 
             // Sign and finalize the proposal PSBT
             let payjoin_proposal = payjoin
@@ -753,7 +748,7 @@ mod integration {
             let (bitcoind, sender, receiver) = init_bitcoind_sender_receiver()?;
             // Generate more UTXOs for the receiver
             let receiver_address =
-                receiver.get_new_address(None, Some(AddressType::Bech32))?.assume_checked();
+                receiver.get_new_address(None, Some(AddressType::P2shSegwit))?.assume_checked();
             bitcoind.client.generate_to_address(199, &receiver_address)?;
             let receiver_utxos = receiver.list_unspent(None, None, None, None, None).unwrap();
             assert_eq!(100, receiver_utxos.len(), "receiver doesn't have enough UTXOs");
@@ -796,17 +791,7 @@ mod integration {
                     .script_pubkey(),
             }];
             let drain_script = outputs[0].script_pubkey.clone();
-            let inputs = receiver_utxos
-                .iter()
-                .map(|utxo| {
-                    let outpoint = OutPoint { txid: utxo.txid, vout: utxo.vout };
-                    let txo = bitcoin::TxOut {
-                        value: utxo.amount,
-                        script_pubkey: utxo.script_pub_key.clone(),
-                    };
-                    (outpoint, txo)
-                })
-                .collect();
+            let inputs = receiver_utxos.iter().map(input_pair_from_list_unspent).collect();
             let response = handle_v1_pj_request(
                 req,
                 headers,
@@ -953,10 +938,10 @@ mod integration {
         let bitcoind = bitcoind::BitcoinD::with_conf(bitcoind_exe, &conf)?;
         let receiver = bitcoind.create_wallet("receiver")?;
         let receiver_address =
-            receiver.get_new_address(None, Some(AddressType::Bech32))?.assume_checked();
+            receiver.get_new_address(None, Some(AddressType::P2shSegwit))?.assume_checked();
         let sender = bitcoind.create_wallet("sender")?;
         let sender_address =
-            sender.get_new_address(None, Some(AddressType::Bech32))?.assume_checked();
+            sender.get_new_address(None, Some(AddressType::P2shSegwit))?.assume_checked();
         bitcoind.client.generate_to_address(1, &receiver_address)?;
         bitcoind.client.generate_to_address(101, &sender_address)?;
 
@@ -1008,7 +993,7 @@ mod integration {
         receiver: &bitcoincore_rpc::Client,
         custom_outputs: Option<Vec<TxOut>>,
         drain_script: Option<&bitcoin::Script>,
-        custom_inputs: Option<Vec<(OutPoint, TxOut)>>,
+        custom_inputs: Option<Vec<(bitcoin::psbt::Input, bitcoin::TxIn)>>,
     ) -> String {
         // Receiver receive payjoin proposal, IRL it will be an HTTP request (over ssl or onion)
         let proposal = payjoin::receive::UncheckedProposal::from_request(
@@ -1030,7 +1015,7 @@ mod integration {
         receiver: &bitcoincore_rpc::Client,
         custom_outputs: Option<Vec<TxOut>>,
         drain_script: Option<&bitcoin::Script>,
-        custom_inputs: Option<Vec<(OutPoint, TxOut)>>,
+        custom_inputs: Option<Vec<(bitcoin::psbt::Input, bitcoin::TxIn)>>,
     ) -> payjoin::receive::PayjoinProposal {
         // in a payment processor where the sender could go offline, this is where you schedule to broadcast the original_tx
         let _to_broadcast_in_failure_case = proposal.extract_tx_to_schedule_broadcast();
@@ -1100,11 +1085,8 @@ mod integration {
                     .iter()
                     .find(|i| i.txid == selected_outpoint.txid && i.vout == selected_outpoint.vout)
                     .unwrap();
-                let txo_to_contribute = bitcoin::TxOut {
-                    value: selected_utxo.amount,
-                    script_pubkey: selected_utxo.script_pub_key.clone(),
-                };
-                vec![(selected_outpoint, txo_to_contribute)]
+                let input_pair = input_pair_from_list_unspent(selected_utxo);
+                vec![input_pair]
             }
         };
 
@@ -1147,11 +1129,31 @@ mod integration {
 
     fn predicted_tx_weight(tx: &bitcoin::Transaction) -> Weight {
         bitcoin::transaction::predict_weight(
-            vec![bitcoin::transaction::InputWeightPrediction::P2WPKH_MAX; tx.input.len()],
+            vec![bitcoin::transaction::InputWeightPrediction::new(23, [72, 33]); tx.input.len()],
             tx.script_pubkey_lens(),
         )
     }
 
+    fn input_pair_from_list_unspent(
+        utxo: &bitcoind::bitcoincore_rpc::bitcoincore_rpc_json::ListUnspentResultEntry,
+    ) -> (bitcoin::psbt::Input, bitcoin::TxIn) {
+        let psbtin = bitcoin::psbt::Input {
+            // TODO: non_witness_utxo for legacy support
+            witness_utxo: Some(TxOut {
+                value: utxo.amount,
+                script_pubkey: utxo.script_pub_key.clone(),
+            }),
+            redeem_script: utxo.redeem_script.clone(),
+            witness_script: utxo.witness_script.clone(),
+            ..Default::default()
+        };
+        let txin = bitcoin::TxIn {
+            previous_output: OutPoint { txid: utxo.txid, vout: utxo.vout },
+            ..Default::default()
+        };
+        (psbtin, txin)
+    }
+
     struct HeaderMock(HashMap<String, String>);
 
     impl payjoin::receive::Headers for HeaderMock {