Witness with block

.github/workflows/fuzz.yml

@@ -11,7 +11,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        fuzz_target: [deser_net_msg, deserialize_address, deserialize_amount, deserialize_block, deserialize_psbt, deserialize_script, deserialize_transaction, outpoint_string, uint128_fuzz, script_bytes_to_asm_fmt]
+        fuzz_target: [deser_net_msg, deserialize_address, deserialize_amount, deserialize_block, deserialize_psbt, deserialize_script, deserialize_transaction, deserialize_witness, outpoint_string, uint128_fuzz, script_bytes_to_asm_fmt]
     steps:
       - name: Install test dependencies
         run: sudo apt-get update -y && sudo apt-get install -y binutils-dev libunwind8-dev libcurl4-openssl-dev libelf-dev libdw-dev cmake gcc libiberty-dev

fuzz/Cargo.toml

@@ -59,3 +59,7 @@ path = "fuzz_targets/uint128_fuzz.rs"
 [[bin]]
 name = "script_bytes_to_asm_fmt"
 path = "fuzz_targets/script_bytes_to_asm_fmt.rs"
+
+[[bin]]
+name = "deserialize_witness"
+path = "fuzz_targets/deserialize_witness.rs"

fuzz/fuzz_targets/deserialize_transaction.rs

@@ -10,7 +10,7 @@ fn do_test(data: &[u8]) {
             let len = ser.len();
             let calculated_weight = tx.get_weight();
             for input in &mut tx.input {
-                input.witness = vec![];
+                input.witness = bitcoin::blockdata::witness::Witness::default();
             }
             let no_witness_len = bitcoin::consensus::encode::serialize(&tx).len();
             // For 0-input transactions, `no_witness_len` will be incorrect because

fuzz/fuzz_targets/deserialize_witness.rs

@@ -0,0 +1,59 @@
+extern crate bitcoin;
+
+use bitcoin::consensus::{serialize, deserialize};
+use bitcoin::blockdata::witness::Witness;
+
+fn do_test(data: &[u8]) {
+    let w: Result<Witness, _> = deserialize(data);
+    if let Ok(witness) = w {
+        let serialized = serialize(&witness);
+        assert_eq!(data, serialized);
+    }
+}
+
+#[cfg(feature = "afl")]
+#[macro_use] extern crate afl;
+#[cfg(feature = "afl")]
+fn main() {
+    fuzz!(|data| {
+        do_test(&data);
+    });
+}
+
+#[cfg(feature = "honggfuzz")]
+#[macro_use] extern crate honggfuzz;
+#[cfg(feature = "honggfuzz")]
+fn main() {
+    loop {
+        fuzz!(|data| {
+            do_test(data);
+        });
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    fn extend_vec_from_hex(hex: &str, out: &mut Vec<u8>) {
+        let mut b = 0;
+        for (idx, c) in hex.as_bytes().iter().enumerate() {
+            b <<= 4;
+            match *c {
+                b'A'..=b'F' => b |= c - b'A' + 10,
+                b'a'..=b'f' => b |= c - b'a' + 10,
+                b'0'..=b'9' => b |= c - b'0',
+                _ => panic!("Bad hex"),
+            }
+            if (idx & 1) == 1 {
+                out.push(b);
+                b = 0;
+            }
+        }
+    }
+
+    #[test]
+    fn duplicate_crash() {
+        let mut a = Vec::new();
+        extend_vec_from_hex("00", &mut a);
+        super::do_test(&a);
+    }
+}

src/blockdata/block.rs

@@ -199,9 +199,10 @@ impl Block {
                         o.script_pubkey[0..6] == [0x6a, 0x24, 0xaa, 0x21, 0xa9, 0xed] }) {
                     let commitment = WitnessCommitment::from_slice(&coinbase.output[pos].script_pubkey.as_bytes()[6..38]).unwrap();
                     // witness reserved value is in coinbase input witness
-                    if coinbase.input[0].witness.len() == 1 && coinbase.input[0].witness[0].len() == 32 {
+                    let witness_vec: Vec<_> = coinbase.input[0].witness.iter().collect();
+                    if witness_vec.len() == 1 && witness_vec[0].len() == 32 {
                         match self.witness_root() {
-                            Some(witness_root) => return commitment == Self::compute_witness_commitment(&witness_root, coinbase.input[0].witness[0].as_slice()),
+                            Some(witness_root) => return commitment == Self::compute_witness_commitment(&witness_root, witness_vec[0]),
                             None => return false,
                         }
                     }

src/blockdata/constants.rs

@@ -29,6 +29,7 @@ use blockdata::opcodes;
 use blockdata::script;
 use blockdata::transaction::{OutPoint, Transaction, TxOut, TxIn};
 use blockdata::block::{Block, BlockHeader};
+use blockdata::witness::Witness;
 use network::constants::Network;
 use util::uint::Uint256;
 
@@ -93,7 +94,7 @@ fn bitcoin_genesis_tx() -> Transaction {
         previous_output: OutPoint::null(),
         script_sig: in_script,
         sequence: MAX_SEQUENCE,
-        witness: vec![],
+        witness: Witness::default(),
     });
 
     // Outputs

src/blockdata/mod.rs

@@ -23,4 +23,5 @@ pub mod opcodes;
 pub mod script;
 pub mod transaction;
 pub mod block;
+pub mod witness;
 

src/blockdata/transaction.rs

@@ -36,6 +36,7 @@ use util::endian;
 use blockdata::constants::WITNESS_SCALE_FACTOR;
 #[cfg(feature="bitcoinconsensus")] use blockdata::script;
 use blockdata::script::Script;
+use blockdata::witness::Witness;
 use consensus::{encode, Decodable, Encodable};
 use consensus::encode::MAX_VEC_SIZE;
 use hash_types::{SigHash, Txid, Wtxid};
@@ -197,7 +198,7 @@ pub struct TxIn {
     /// Encodable/Decodable, as it is (de)serialized at the end of the full
     /// Transaction. It *is* (de)serialized with the rest of the TxIn in other
     /// (de)serialization routines.
-    pub witness: Vec<Vec<u8>>
+    pub witness: Witness
 }
 
 impl Default for TxIn {
@@ -206,7 +207,7 @@ impl Default for TxIn {
             previous_output: OutPoint::default(),
             script_sig: Script::new(),
             sequence: u32::max_value(),
-            witness: Vec::new(),
+            witness: Witness::default(),
         }
     }
 }
@@ -280,7 +281,7 @@ impl Transaction {
         let cloned_tx = Transaction {
             version: self.version,
             lock_time: self.lock_time,
-            input: self.input.iter().map(|txin| TxIn { script_sig: Script::new(), witness: vec![], .. *txin }).collect(),
+            input: self.input.iter().map(|txin| TxIn { script_sig: Script::new(), witness: Witness::default(), .. *txin }).collect(),
             output: self.output.clone(),
         };
         cloned_tx.txid().into()
@@ -357,7 +358,7 @@ impl Transaction {
                 previous_output: self.input[input_index].previous_output,
                 script_sig: script_pubkey.clone(),
                 sequence: self.input[input_index].sequence,
-                witness: vec![],
+                witness: Witness::default(),
             }];
         } else {
             tx.input = Vec::with_capacity(self.input.len());
@@ -366,7 +367,7 @@ impl Transaction {
                     previous_output: input.previous_output,
                     script_sig: if n == input_index { script_pubkey.clone() } else { Script::new() },
                     sequence: if n != input_index && (sighash == EcdsaSigHashType::Single || sighash == EcdsaSigHashType::None) { 0 } else { input.sequence },
-                    witness: vec![],
+                    witness: Witness::default(),
                 });
             }
         }
@@ -473,10 +474,7 @@ impl Transaction {
                 input.script_sig.len());
             if !input.witness.is_empty() {
                 inputs_with_witnesses += 1;
-                input_weight += VarInt(input.witness.len() as u64).len();
-                for elem in &input.witness {
-                    input_weight += VarInt(elem.len() as u64).len() + elem.len();
-                }
+                input_weight += input.witness.serialized_len();
             }
         }
         let mut output_size = 0;
@@ -578,7 +576,7 @@ impl Decodable for TxIn {
             previous_output: Decodable::consensus_decode(&mut d)?,
             script_sig: Decodable::consensus_decode(&mut d)?,
             sequence: Decodable::consensus_decode(d)?,
-            witness: vec![],
+            witness: Witness::default(),
         })
     }
 }
@@ -1471,7 +1469,9 @@ mod tests {
         }).is_err());
 
         // test that we get a failure if we corrupt a signature
-        spending.input[1].witness[0][10] = 42;
+        let mut witness: Vec<_> = spending.input[1].witness.iter().map(|el| el.to_vec()).collect();
+        witness[0][10] = 42;
+        spending.input[1].witness = witness.into();
         match spending.verify(|point: &OutPoint| {
             if let Some(tx) = spent3.remove(&point.txid) {
                 return tx.output.get(point.vout as usize).cloned();