implement satisfier for psbt

Author: sanket1729

src/lib.rs

@@ -129,8 +129,6 @@ pub use miniscript::decode::Terminal;
 pub use miniscript::satisfy::{Preimage32, Satisfier};
 pub use miniscript::Miniscript;
 
-// Use schnorr pubkey as Xonlykey
-pub(crate) use bitcoin::schnorr::PublicKey as XOnlyKey;
 
 ///Public key trait which can be converted to Hash type
 pub trait MiniscriptKey: Clone + Eq + Ord + fmt::Debug + fmt::Display + hash::Hash {

src/psbt/finalizer.rs

@@ -24,6 +24,7 @@ use util::{script_is_v1_tr, witness_size};
 use super::{sanity_check, Psbt};
 use super::{Error, InputError, PsbtInputSatisfier};
 use bitcoin::blockdata::witness::Witness;
+use bitcoin::secp256k1::XOnlyPublicKey;
 use bitcoin::secp256k1::{self, Secp256k1};
 use bitcoin::util::taproot::LeafVersion;
 use bitcoin::{self, PublicKey, Script};
@@ -32,7 +33,6 @@ use interpreter;
 use Descriptor;
 use Miniscript;
 use Satisfier;
-use XOnlyKey;
 use {BareCtx, Legacy, Segwitv0, Tap};
 
 // Satisfy the taproot descriptor. It is not possible to infer the complete
@@ -47,20 +47,22 @@ fn construct_tap_witness(
     assert!(script_is_v1_tr(&spk));
 
     // try the script spend path first
-    if let Some(sig) = <PsbtInputSatisfier as Satisfier<XOnlyKey>>::lookup_tap_key_spend_sig(sat) {
+    if let Some(sig) =
+        <PsbtInputSatisfier as Satisfier<XOnlyPublicKey>>::lookup_tap_key_spend_sig(sat)
+    {
         return Ok(vec![sig.to_vec()]);
     }
     // Next script spends
     let (mut min_wit, mut min_wit_len) = (None, None);
     if let Some(block_map) =
-        <PsbtInputSatisfier as Satisfier<XOnlyKey>>::lookup_tap_control_block_map(sat)
+        <PsbtInputSatisfier as Satisfier<XOnlyPublicKey>>::lookup_tap_control_block_map(sat)
     {
         for (control_block, (script, ver)) in block_map {
-            if *ver != LeafVersion::default() {
+            if *ver != LeafVersion::TapScript {
                 // We don't know how to satisfy non default version scripts yet
                 continue;
             }
-            let ms = match Miniscript::<XOnlyKey, Tap>::parse_insane(script) {
+            let ms = match Miniscript::<XOnlyPublicKey, Tap>::parse_insane(script) {
                 Ok(ms) => ms,
                 Err(..) => continue, // try another script
             };

src/psbt/mod.rs

@@ -19,6 +19,7 @@
 //! `https://github.com/bitcoin/bips/blob/master/bip-0174.mediawiki`
 //!
 
+use std::collections::BTreeMap;
 use std::{error, fmt};
 
 use bitcoin;
@@ -28,6 +29,7 @@ use bitcoin::secp256k1::{self, Secp256k1};
 use bitcoin::util::psbt::PartiallySignedTransaction as Psbt;
 use bitcoin::Script;
 
+use bitcoin::util::taproot::{ControlBlock, LeafVersion, TapLeafHash};
 use interpreter;
 use miniscript::limits::SEQUENCE_LOCKTIME_DISABLE_FLAG;
 use miniscript::satisfy::{After, Older};
@@ -232,6 +234,37 @@ impl<'psbt> PsbtInputSatisfier<'psbt> {
 }
 
 impl<'psbt, Pk: MiniscriptKey + ToPublicKey> Satisfier<Pk> for PsbtInputSatisfier<'psbt> {
+    fn lookup_tap_key_spend_sig(&self) -> Option<bitcoin::SchnorrSig> {
+        self.psbt.inputs[self.index].tap_key_sig
+    }
+
+    fn lookup_tap_leaf_script_sig(&self, pk: &Pk, lh: &TapLeafHash) -> Option<bitcoin::SchnorrSig> {
+        self.psbt.inputs[self.index]
+            .tap_script_sigs
+            .get(&(pk.to_x_only_pubkey(), *lh))
+            .map(|x| *x) // replace by copied in 1.36
+    }
+
+    fn lookup_tap_control_block_map(
+        &self,
+    ) -> Option<&BTreeMap<ControlBlock, (bitcoin::Script, LeafVersion)>> {
+        Some(&self.psbt.inputs[self.index].tap_scripts)
+    }
+
+    fn lookup_pkh_tap_leaf_script_sig(
+        &self,
+        pkh: &(Pk::Hash, TapLeafHash),
+    ) -> Option<(bitcoin::secp256k1::XOnlyPublicKey, bitcoin::SchnorrSig)> {
+        self.psbt.inputs[self.index]
+            .tap_script_sigs
+            .iter()
+            .filter(|&((pubkey, lh), _sig)| {
+                pubkey.to_pubkeyhash() == Pk::hash_to_hash160(&pkh.0) && *lh == pkh.1
+            })
+            .next()
+            .map(|((x_only_pk, _leaf_hash), sig)| (*x_only_pk, *sig))
+    }
+
     fn lookup_ecdsa_sig(&self, pk: &Pk) -> Option<bitcoin::EcdsaSig> {
         self.psbt.inputs[self.index]
             .partial_sigs