Add psbt preimage satisfaction logic

Improving PSBT preimage satisfation

Co-authored-by: Dr Maxim Orlovsky <orlovsky@pandoracore.com>

Author: sanket1729

src/psbt/mod.rs

@@ -22,15 +22,16 @@
 use std::{error, fmt};
 
 use bitcoin;
+use bitcoin::hashes::{hash160, ripemd160, sha256, sha256d};
 use bitcoin::secp256k1::{self, Secp256k1};
 use bitcoin::util::psbt::PartiallySignedTransaction as Psbt;
 use bitcoin::Script;
 
 use interpreter;
 use miniscript::limits::SEQUENCE_LOCKTIME_DISABLE_FLAG;
 use miniscript::satisfy::{bitcoinsig_from_rawsig, After, Older};
-use BitcoinSig;
 use Satisfier;
+use {BitcoinSig, Preimage32};
 use {MiniscriptKey, ToPublicKey};
 
 mod finalizer;
@@ -279,6 +280,44 @@ impl<'psbt, Pk: MiniscriptKey + ToPublicKey> Satisfier<Pk> for PsbtInputSatisfie
             <Satisfier<Pk>>::check_older(&Older(seq), n)
         }
     }
+
+    fn lookup_hash160(&self, h: hash160::Hash) -> Option<Preimage32> {
+        self.psbt.inputs[self.index]
+            .hash160_preimages
+            .get(&h)
+            .and_then(try_vec_as_preimage32)
+    }
+
+    fn lookup_sha256(&self, h: sha256::Hash) -> Option<Preimage32> {
+        self.psbt.inputs[self.index]
+            .sha256_preimages
+            .get(&h)
+            .and_then(try_vec_as_preimage32)
+    }
+
+    fn lookup_hash256(&self, h: sha256d::Hash) -> Option<Preimage32> {
+        self.psbt.inputs[self.index]
+            .hash256_preimages
+            .get(&h)
+            .and_then(try_vec_as_preimage32)
+    }
+
+    fn lookup_ripemd160(&self, h: ripemd160::Hash) -> Option<Preimage32> {
+        self.psbt.inputs[self.index]
+            .ripemd160_preimages
+            .get(&h)
+            .and_then(try_vec_as_preimage32)
+    }
+}
+
+fn try_vec_as_preimage32(vec: &Vec<u8>) -> Option<Preimage32> {
+    if vec.len() == 32 {
+        let mut arr = [0u8; 32];
+        arr.copy_from_slice(&vec);
+        Some(arr)
+    } else {
+        None
+    }
 }
 
 fn sanity_check(psbt: &Psbt) -> Result<(), Error> {