Merge tcharding/rust-psbt#94: Handle multi byte keytypes in Key::decode and Key::encode

3d23615 fix: handle multi byte keytypes in Key::decode and Key::encode (nymius)
d47ab6d fix: encode keytype as u64 instead of u8 (nymius)

Pull request description:

  `<keytype>` as specified by BIP 174 may be represented with up to 8 bytes, even if minimally encoded.

  Because the currently specified fields weren't using as many bytes, we were only considering the single byte case in the `Key::decode` and `Key::encode` logic.

  Here we change this logic to address larger `<keytypes>` and follow the specification.

  Stacks on top of: #90, #93.
  Fixes #78.

ACKs for top commit:
  nyonson:
    ACK 3d23615
  tcharding:
    ACK 3d23615

Tree-SHA512: f6d12532eabd702979020835f23f7e588620014f8850e15d02dcbea20f253eea894f5a9f36b95d66a55f0e38a3b6a6701e8ca06aff88f6c70eb57600d59c9ef1

Author: tcharding

src/consts.rs

@@ -8,117 +8,117 @@
 #![allow(dead_code)]
 
 /// Type: Unsigned Transaction PSBT_GLOBAL_UNSIGNED_TX = 0x00
-pub(crate) const PSBT_GLOBAL_UNSIGNED_TX: u8 = 0x00;
+pub(crate) const PSBT_GLOBAL_UNSIGNED_TX: u64 = 0x00;
 /// Type: Extended Public Key PSBT_GLOBAL_XPUB = 0x01
-pub(crate) const PSBT_GLOBAL_XPUB: u8 = 0x01;
+pub(crate) const PSBT_GLOBAL_XPUB: u64 = 0x01;
 /// Type: Transaction Version PSBT_GLOBAL_TX_VERSION = 0x02
-pub(crate) const PSBT_GLOBAL_TX_VERSION: u8 = 0x02;
+pub(crate) const PSBT_GLOBAL_TX_VERSION: u64 = 0x02;
 /// Type: Fallback Locktime PSBT_GLOBAL_FALLBACK_LOCKTIME = 0x03
-pub(crate) const PSBT_GLOBAL_FALLBACK_LOCKTIME: u8 = 0x03;
+pub(crate) const PSBT_GLOBAL_FALLBACK_LOCKTIME: u64 = 0x03;
 /// Type: Input Count PSBT_GLOBAL_INPUT_COUNT = 0x04
-pub(crate) const PSBT_GLOBAL_INPUT_COUNT: u8 = 0x04;
+pub(crate) const PSBT_GLOBAL_INPUT_COUNT: u64 = 0x04;
 /// Type: Output Count PSBT_GLOBAL_OUTPUT_COUNT = 0x05
-pub(crate) const PSBT_GLOBAL_OUTPUT_COUNT: u8 = 0x05;
+pub(crate) const PSBT_GLOBAL_OUTPUT_COUNT: u64 = 0x05;
 /// Type: Transaction Modifiable Flags PSBT_GLOBAL_TX_MODIFIABLE = 0x06
-pub(crate) const PSBT_GLOBAL_TX_MODIFIABLE: u8 = 0x06;
+pub(crate) const PSBT_GLOBAL_TX_MODIFIABLE: u64 = 0x06;
 #[cfg(feature = "silent-payments")]
 /// Type: Silent Payment ECDH Share PSBT_GLOBAL_SP_ECDH_SHARE = 0x07
-pub(crate) const PSBT_GLOBAL_SP_ECDH_SHARE: u8 = 0x07;
+pub(crate) const PSBT_GLOBAL_SP_ECDH_SHARE: u64 = 0x07;
 #[cfg(feature = "silent-payments")]
 /// Type: Silent Payment DLEQ PSBT_GLOBAL_SP_DLEQ = 0x08
-pub(crate) const PSBT_GLOBAL_SP_DLEQ: u8 = 0x08;
+pub(crate) const PSBT_GLOBAL_SP_DLEQ: u64 = 0x08;
 /// Type: Version Number PSBT_GLOBAL_VERSION = 0xFB
-pub(crate) const PSBT_GLOBAL_VERSION: u8 = 0xFB;
+pub(crate) const PSBT_GLOBAL_VERSION: u64 = 0xFB;
 /// Type: Proprietary Use Type PSBT_GLOBAL_PROPRIETARY = 0xFC
-pub(crate) const PSBT_GLOBAL_PROPRIETARY: u8 = 0xFC;
+pub(crate) const PSBT_GLOBAL_PROPRIETARY: u64 = 0xFC;
 
 /// Type: Non-Witness UTXO PSBT_IN_NON_WITNESS_UTXO = 0x00
-pub(crate) const PSBT_IN_NON_WITNESS_UTXO: u8 = 0x00;
+pub(crate) const PSBT_IN_NON_WITNESS_UTXO: u64 = 0x00;
 /// Type: Witness UTXO PSBT_IN_WITNESS_UTXO = 0x01
-pub(crate) const PSBT_IN_WITNESS_UTXO: u8 = 0x01;
+pub(crate) const PSBT_IN_WITNESS_UTXO: u64 = 0x01;
 /// Type: Partial Signature PSBT_IN_PARTIAL_SIG = 0x02
-pub(crate) const PSBT_IN_PARTIAL_SIG: u8 = 0x02;
+pub(crate) const PSBT_IN_PARTIAL_SIG: u64 = 0x02;
 /// Type: Sighash Type PSBT_IN_SIGHASH_TYPE = 0x03
-pub(crate) const PSBT_IN_SIGHASH_TYPE: u8 = 0x03;
+pub(crate) const PSBT_IN_SIGHASH_TYPE: u64 = 0x03;
 /// Type: Redeem Script PSBT_IN_REDEEM_SCRIPT = 0x04
-pub(crate) const PSBT_IN_REDEEM_SCRIPT: u8 = 0x04;
+pub(crate) const PSBT_IN_REDEEM_SCRIPT: u64 = 0x04;
 /// Type: Witness Script PSBT_IN_WITNESS_SCRIPT = 0x05
-pub(crate) const PSBT_IN_WITNESS_SCRIPT: u8 = 0x05;
+pub(crate) const PSBT_IN_WITNESS_SCRIPT: u64 = 0x05;
 /// Type: BIP 32 Derivation Path PSBT_IN_BIP32_DERIVATION = 0x06
-pub(crate) const PSBT_IN_BIP32_DERIVATION: u8 = 0x06;
+pub(crate) const PSBT_IN_BIP32_DERIVATION: u64 = 0x06;
 /// Type: Finalized scriptSig PSBT_IN_FINAL_SCRIPTSIG = 0x07
-pub(crate) const PSBT_IN_FINAL_SCRIPTSIG: u8 = 0x07;
+pub(crate) const PSBT_IN_FINAL_SCRIPTSIG: u64 = 0x07;
 /// Type: Finalized scriptWitness PSBT_IN_FINAL_SCRIPTWITNESS = 0x08
-pub(crate) const PSBT_IN_FINAL_SCRIPTWITNESS: u8 = 0x08;
+pub(crate) const PSBT_IN_FINAL_SCRIPTWITNESS: u64 = 0x08;
 /// Type: Proof-of-reserves commitment PSBT_IN_POR_COMMITMENT = 0x09
 #[allow(unused)] // PSBT v0
-pub(crate) const PSBT_IN_POR_COMMITMENT: u8 = 0x09;
+pub(crate) const PSBT_IN_POR_COMMITMENT: u64 = 0x09;
 /// Type: RIPEMD160 preimage PSBT_IN_RIPEMD160 = 0x0a
-pub(crate) const PSBT_IN_RIPEMD160: u8 = 0x0a;
+pub(crate) const PSBT_IN_RIPEMD160: u64 = 0x0a;
 /// Type: SHA256 preimage PSBT_IN_SHA256 = 0x0b
-pub(crate) const PSBT_IN_SHA256: u8 = 0x0b;
+pub(crate) const PSBT_IN_SHA256: u64 = 0x0b;
 /// Type: HASH160 preimage PSBT_IN_HASH160 = 0x0c
-pub(crate) const PSBT_IN_HASH160: u8 = 0x0c;
+pub(crate) const PSBT_IN_HASH160: u64 = 0x0c;
 /// Type: HASH256 preimage PSBT_IN_HASH256 = 0x0d
-pub(crate) const PSBT_IN_HASH256: u8 = 0x0d;
+pub(crate) const PSBT_IN_HASH256: u64 = 0x0d;
 /// Type: Previous TXID PSBT_IN_PREVIOUS_TXID = 0x0e
-pub(crate) const PSBT_IN_PREVIOUS_TXID: u8 = 0x0e;
+pub(crate) const PSBT_IN_PREVIOUS_TXID: u64 = 0x0e;
 /// Type: Spent Output Index PSBT_IN_OUTPUT_INDEX = 0x0f
-pub(crate) const PSBT_IN_OUTPUT_INDEX: u8 = 0x0f;
+pub(crate) const PSBT_IN_OUTPUT_INDEX: u64 = 0x0f;
 /// Type: Sequence Number PSBT_IN_SEQUENCE = 0x10
-pub(crate) const PSBT_IN_SEQUENCE: u8 = 0x10;
+pub(crate) const PSBT_IN_SEQUENCE: u64 = 0x10;
 /// Type: Required Time-based Locktime PSBT_IN_REQUIRED_TIME_LOCKTIME = 0x11
-pub(crate) const PSBT_IN_REQUIRED_TIME_LOCKTIME: u8 = 0x11;
+pub(crate) const PSBT_IN_REQUIRED_TIME_LOCKTIME: u64 = 0x11;
 /// Type: Required Height-based Locktime PSBT_IN_REQUIRED_HEIGHT_LOCKTIME = 0x12
-pub(crate) const PSBT_IN_REQUIRED_HEIGHT_LOCKTIME: u8 = 0x12;
+pub(crate) const PSBT_IN_REQUIRED_HEIGHT_LOCKTIME: u64 = 0x12;
 /// Type: Taproot Signature in Key Spend PSBT_IN_TAP_KEY_SIG = 0x13
-pub(crate) const PSBT_IN_TAP_KEY_SIG: u8 = 0x13;
+pub(crate) const PSBT_IN_TAP_KEY_SIG: u64 = 0x13;
 /// Type: Taproot Signature in Script Spend PSBT_IN_TAP_SCRIPT_SIG = 0x14
-pub(crate) const PSBT_IN_TAP_SCRIPT_SIG: u8 = 0x14;
+pub(crate) const PSBT_IN_TAP_SCRIPT_SIG: u64 = 0x14;
 /// Type: Taproot Leaf Script PSBT_IN_TAP_LEAF_SCRIPT = 0x14
-pub(crate) const PSBT_IN_TAP_LEAF_SCRIPT: u8 = 0x15;
+pub(crate) const PSBT_IN_TAP_LEAF_SCRIPT: u64 = 0x15;
 /// Type: Taproot Key BIP 32 Derivation Path PSBT_IN_TAP_BIP32_DERIVATION = 0x16
-pub(crate) const PSBT_IN_TAP_BIP32_DERIVATION: u8 = 0x16;
+pub(crate) const PSBT_IN_TAP_BIP32_DERIVATION: u64 = 0x16;
 /// Type: Taproot Internal Key PSBT_IN_TAP_INTERNAL_KEY = 0x17
-pub(crate) const PSBT_IN_TAP_INTERNAL_KEY: u8 = 0x17;
+pub(crate) const PSBT_IN_TAP_INTERNAL_KEY: u64 = 0x17;
 /// Type: Taproot Merkle Root PSBT_IN_TAP_MERKLE_ROOT = 0x18
-pub(crate) const PSBT_IN_TAP_MERKLE_ROOT: u8 = 0x18;
+pub(crate) const PSBT_IN_TAP_MERKLE_ROOT: u64 = 0x18;
 #[cfg(feature = "silent-payments")]
 /// Type: Silent Payment ECDH Share PSBT_IN_SP_ECDH_SHARE = 0x1D
-pub(crate) const PSBT_IN_SP_ECDH_SHARE: u8 = 0x1D;
+pub(crate) const PSBT_IN_SP_ECDH_SHARE: u64 = 0x1D;
 #[cfg(feature = "silent-payments")]
 /// Type: Silent Payment DLEQ Proof PSBT_IN_SP_DLEQ = 0x1E
-pub(crate) const PSBT_IN_SP_DLEQ: u8 = 0x1E;
+pub(crate) const PSBT_IN_SP_DLEQ: u64 = 0x1E;
 /// Type: Proprietary Use Type PSBT_IN_PROPRIETARY = 0xFC
-pub(crate) const PSBT_IN_PROPRIETARY: u8 = 0xFC;
+pub(crate) const PSBT_IN_PROPRIETARY: u64 = 0xFC;
 
 /// Type: Redeem ScriptBuf PSBT_OUT_REDEEM_SCRIPT = 0x00
-pub(crate) const PSBT_OUT_REDEEM_SCRIPT: u8 = 0x00;
+pub(crate) const PSBT_OUT_REDEEM_SCRIPT: u64 = 0x00;
 /// Type: Witness ScriptBuf PSBT_OUT_WITNESS_SCRIPT = 0x01
-pub(crate) const PSBT_OUT_WITNESS_SCRIPT: u8 = 0x01;
+pub(crate) const PSBT_OUT_WITNESS_SCRIPT: u64 = 0x01;
 /// Type: BIP 32 Derivation Path PSBT_OUT_BIP32_DERIVATION = 0x02
-pub(crate) const PSBT_OUT_BIP32_DERIVATION: u8 = 0x02;
+pub(crate) const PSBT_OUT_BIP32_DERIVATION: u64 = 0x02;
 /// Type: Output Amount PSBT_OUT_AMOUNT = 0x03
-pub(crate) const PSBT_OUT_AMOUNT: u8 = 0x03;
+pub(crate) const PSBT_OUT_AMOUNT: u64 = 0x03;
 /// Type: Output Script PSBT_OUT_SCRIPT = 0x04
-pub(crate) const PSBT_OUT_SCRIPT: u8 = 0x04;
+pub(crate) const PSBT_OUT_SCRIPT: u64 = 0x04;
 /// Type: Taproot Internal Key PSBT_OUT_TAP_INTERNAL_KEY = 0x05
-pub(crate) const PSBT_OUT_TAP_INTERNAL_KEY: u8 = 0x05;
+pub(crate) const PSBT_OUT_TAP_INTERNAL_KEY: u64 = 0x05;
 /// Type: Taproot Tree PSBT_OUT_TAP_TREE = 0x06
-pub(crate) const PSBT_OUT_TAP_TREE: u8 = 0x06;
+pub(crate) const PSBT_OUT_TAP_TREE: u64 = 0x06;
 /// Type: Taproot Key BIP 32 Derivation Path PSBT_OUT_TAP_BIP32_DERIVATION = 0x07
-pub(crate) const PSBT_OUT_TAP_BIP32_DERIVATION: u8 = 0x07;
+pub(crate) const PSBT_OUT_TAP_BIP32_DERIVATION: u64 = 0x07;
 #[cfg(feature = "silent-payments")]
 /// Type: Silent Payment v0 Info PSBT_OUT_SP_V0_INFO = 0x09
-pub(crate) const PSBT_OUT_SP_V0_INFO: u8 = 0x09;
+pub(crate) const PSBT_OUT_SP_V0_INFO: u64 = 0x09;
 #[cfg(feature = "silent-payments")]
 /// Type: Silent Payment v0 Label PSBT_OUT_SP_V0_LABEL = 0x0A
-pub(crate) const PSBT_OUT_SP_V0_LABEL: u8 = 0x0A;
+pub(crate) const PSBT_OUT_SP_V0_LABEL: u64 = 0x0A;
 /// Type: Proprietary Use Type PSBT_IN_PROPRIETARY = 0xFC
-pub(crate) const PSBT_OUT_PROPRIETARY: u8 = 0xFC;
+pub(crate) const PSBT_OUT_PROPRIETARY: u64 = 0xFC;
 
 /// Converts a global key type value consts to a string, useful for debugging.
-pub(crate) fn psbt_global_key_type_value_to_str(v: u8) -> &'static str {
+pub(crate) fn psbt_global_key_type_value_to_str(v: u64) -> &'static str {
     match v {
         PSBT_GLOBAL_UNSIGNED_TX => "PSBT_GLOBAL_UNSIGNED_TX",
         PSBT_GLOBAL_XPUB => "PSBT_GLOBAL_XPUB",
@@ -138,7 +138,7 @@ pub(crate) fn psbt_global_key_type_value_to_str(v: u8) -> &'static str {
 }
 
 /// Converts an input key type value consts to a string, useful for debugging.
-pub(crate) fn psbt_in_key_type_value_to_str(v: u8) -> &'static str {
+pub(crate) fn psbt_in_key_type_value_to_str(v: u64) -> &'static str {
     match v {
         PSBT_IN_NON_WITNESS_UTXO => "PSBT_IN_NON_WITNESS_UTXO",
         PSBT_IN_WITNESS_UTXO => "PSBT_IN_WITNESS_UTXO",
@@ -175,7 +175,7 @@ pub(crate) fn psbt_in_key_type_value_to_str(v: u8) -> &'static str {
 }
 
 /// Converts an output key type value consts to a string, useful for debugging.
-pub(crate) fn psbt_out_key_type_value_to_str(v: u8) -> &'static str {
+pub(crate) fn psbt_out_key_type_value_to_str(v: u64) -> &'static str {
     match v {
         PSBT_OUT_REDEEM_SCRIPT => "PSBT_OUT_REDEEM_SCRIPT",
         PSBT_OUT_WITNESS_SCRIPT => "PSBT_OUT_WITNESS_SCRIPT",

src/raw.rs

@@ -77,7 +77,7 @@ impl Deserialize for Pair {
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 pub struct Key {
     /// The `keytype` of this PSBT map key (`keytype`).
-    pub type_value: u8,
+    pub type_value: u64,
     /// The `keydata` itself in raw byte form.
     #[cfg_attr(feature = "serde", serde(with = "crate::serde_utils::hex_bytes"))]
     pub key: Vec<u8>,
@@ -91,7 +91,18 @@ impl Key {
             return Err(serialize::Error::NoMorePairs);
         }
 
-        let key_byte_size: u64 = byte_size - 1;
+        let type_value: VarInt = Decodable::consensus_decode(r)?;
+
+        let key_byte_size = match byte_size.checked_sub(
+            u64::try_from(type_value.size()).expect("size() returns 1-9, fits inside u64"),
+        ) {
+            Some(val) => val,
+            None => {
+                return Err(consensus::Error::ParseFailed(
+                    "encoded keytype is larger than specified length",
+                ))?;
+            }
+        };
 
         if key_byte_size > MAX_VEC_SIZE as u64 {
             return Err(consensus::Error::OversizedVectorAllocation {
@@ -101,25 +112,24 @@ impl Key {
             .into());
         }
 
-        let type_value: u8 = Decodable::consensus_decode(r)?;
-
         let mut key = Vec::with_capacity(key_byte_size as usize);
         for _ in 0..key_byte_size {
             key.push(Decodable::consensus_decode(r)?);
         }
 
-        Ok(Key { type_value, key })
+        Ok(Key { type_value: type_value.0, key })
     }
 }
 
 impl Serialize for Key {
     fn serialize(&self) -> Vec<u8> {
         let mut buf = Vec::new();
-        VarInt::from(self.key.len() + 1)
+        let type_value = VarInt::from(self.type_value);
+        VarInt::from(self.key.len() + type_value.size())
             .consensus_encode(&mut buf)
             .expect("in-memory writers don't error");
 
-        self.type_value.consensus_encode(&mut buf).expect("in-memory writers don't error");
+        type_value.consensus_encode(&mut buf).expect("in-memory writers don't error");
 
         for key in &self.key {
             key.consensus_encode(&mut buf).expect("in-memory writers don't error");

src/v0/bitcoin/error.rs

@@ -106,7 +106,7 @@ pub enum Error {
     /// Key must be excluded from this version of PSBT (see consts.rs for u8 values).
     ExcludedKey {
         /// The disallowed valued.
-        key_type_value: u8,
+        key_type_value: u64,
     },
 }
 

src/v0/bitcoin/map/global.rs

@@ -13,28 +13,27 @@ use crate::v0::bitcoin::map::Map;
 use crate::v0::bitcoin::{raw, Error, Psbt};
 
 /// Type: Unsigned Transaction PSBT_GLOBAL_UNSIGNED_TX = 0x00
-const PSBT_GLOBAL_UNSIGNED_TX: u8 = 0x00;
+const PSBT_GLOBAL_UNSIGNED_TX: u64 = 0x00;
 /// Type: Extended Public Key PSBT_GLOBAL_XPUB = 0x01
-const PSBT_GLOBAL_XPUB: u8 = 0x01;
+const PSBT_GLOBAL_XPUB: u64 = 0x01;
 /// Type: Transaction Version PSBT_GLOBAL_TX_VERSION = 0x02
-const PSBT_GLOBAL_TX_VERSION: u8 = 0x02;
+const PSBT_GLOBAL_TX_VERSION: u64 = 0x02;
 /// Type: Fallback Locktime PSBT_GLOBAL_FALLBACK_LOCKTIME = 0x03
-const PSBT_GLOBAL_FALLBACK_LOCKTIME: u8 = 0x03;
+const PSBT_GLOBAL_FALLBACK_LOCKTIME: u64 = 0x03;
 /// Type: Input Count PSBT_GLOBAL_INPUT_COUNT = 0x04
-const PSBT_GLOBAL_INPUT_COUNT: u8 = 0x04;
+const PSBT_GLOBAL_INPUT_COUNT: u64 = 0x04;
 /// Type: Output Count PSBT_GLOBAL_OUTPUT_COUNT = 0x05
-const PSBT_GLOBAL_OUTPUT_COUNT: u8 = 0x05;
+const PSBT_GLOBAL_OUTPUT_COUNT: u64 = 0x05;
 /// Type: Transaction Modifiable Flags PSBT_GLOBAL_TX_MODIFIABLE = 0x06
-const PSBT_GLOBAL_TX_MODIFIABLE: u8 = 0x06;
+const PSBT_GLOBAL_TX_MODIFIABLE: u64 = 0x06;
 /// Type: Version Number PSBT_GLOBAL_SP_ECDH_SHARE = 0x07
-const PSBT_GLOBAL_SP_ECDH_SHARE: u8 = 0x07;
+const PSBT_GLOBAL_SP_ECDH_SHARE: u64 = 0x07;
 /// Type: Version Number PSBT_GLOBAL_SP_DLEQ = 0x08
-const PSBT_GLOBAL_SP_DLEQ: u8 = 0x08;
+const PSBT_GLOBAL_SP_DLEQ: u64 = 0x08;
 /// Type: Version Number PSBT_GLOBAL_VERSION = 0xFB
-const PSBT_GLOBAL_VERSION: u8 = 0xFB;
-
+const PSBT_GLOBAL_VERSION: u64 = 0xFB;
 /// Type: Proprietary Use Type PSBT_GLOBAL_PROPRIETARY = 0xFC
-const PSBT_GLOBAL_PROPRIETARY: u8 = 0xFC;
+const PSBT_GLOBAL_PROPRIETARY: u64 = 0xFC;
 
 impl Map for Psbt {
     fn get_pairs(&self) -> Vec<raw::Pair> {

src/v0/bitcoin/map/input.rs

@@ -20,59 +20,59 @@ use crate::v0::bitcoin::serialize::Deserialize;
 use crate::v0::bitcoin::{self as psbt, error, raw, Error};
 
 /// Type: Non-Witness UTXO PSBT_IN_NON_WITNESS_UTXO = 0x00
-const PSBT_IN_NON_WITNESS_UTXO: u8 = 0x00;
+const PSBT_IN_NON_WITNESS_UTXO: u64 = 0x00;
 /// Type: Witness UTXO PSBT_IN_WITNESS_UTXO = 0x01
-const PSBT_IN_WITNESS_UTXO: u8 = 0x01;
+const PSBT_IN_WITNESS_UTXO: u64 = 0x01;
 /// Type: Partial Signature PSBT_IN_PARTIAL_SIG = 0x02
-const PSBT_IN_PARTIAL_SIG: u8 = 0x02;
+const PSBT_IN_PARTIAL_SIG: u64 = 0x02;
 /// Type: Sighash Type PSBT_IN_SIGHASH_TYPE = 0x03
-const PSBT_IN_SIGHASH_TYPE: u8 = 0x03;
+const PSBT_IN_SIGHASH_TYPE: u64 = 0x03;
 /// Type: Redeem Script PSBT_IN_REDEEM_SCRIPT = 0x04
-const PSBT_IN_REDEEM_SCRIPT: u8 = 0x04;
+const PSBT_IN_REDEEM_SCRIPT: u64 = 0x04;
 /// Type: Witness Script PSBT_IN_WITNESS_SCRIPT = 0x05
-const PSBT_IN_WITNESS_SCRIPT: u8 = 0x05;
+const PSBT_IN_WITNESS_SCRIPT: u64 = 0x05;
 /// Type: BIP 32 Derivation Path PSBT_IN_BIP32_DERIVATION = 0x06
-const PSBT_IN_BIP32_DERIVATION: u8 = 0x06;
+const PSBT_IN_BIP32_DERIVATION: u64 = 0x06;
 /// Type: Finalized scriptSig PSBT_IN_FINAL_SCRIPTSIG = 0x07
-const PSBT_IN_FINAL_SCRIPTSIG: u8 = 0x07;
+const PSBT_IN_FINAL_SCRIPTSIG: u64 = 0x07;
 /// Type: Finalized scriptWitness PSBT_IN_FINAL_SCRIPTWITNESS = 0x08
-const PSBT_IN_FINAL_SCRIPTWITNESS: u8 = 0x08;
+const PSBT_IN_FINAL_SCRIPTWITNESS: u64 = 0x08;
 /// Type: RIPEMD160 preimage PSBT_IN_RIPEMD160 = 0x0a
-const PSBT_IN_RIPEMD160: u8 = 0x0a;
+const PSBT_IN_RIPEMD160: u64 = 0x0a;
 /// Type: SHA256 preimage PSBT_IN_SHA256 = 0x0b
-const PSBT_IN_SHA256: u8 = 0x0b;
+const PSBT_IN_SHA256: u64 = 0x0b;
 /// Type: Previous TXID PSBT_IN_PREVIOUS_TXID = 0x0e
-const PSBT_IN_PREVIOUS_TXID: u8 = 0x0e;
+const PSBT_IN_PREVIOUS_TXID: u64 = 0x0e;
 /// Type: Spent Output Index PSBT_IN_OUTPUT_INDEX = 0x0f
-const PSBT_IN_OUTPUT_INDEX: u8 = 0x0f;
+const PSBT_IN_OUTPUT_INDEX: u64 = 0x0f;
 /// Type: Sequence Number PSBT_IN_SEQUENCE = 0x10
-const PSBT_IN_SEQUENCE: u8 = 0x10;
+const PSBT_IN_SEQUENCE: u64 = 0x10;
 /// Type: Required Time-based Locktime PSBT_IN_REQUIRED_TIME_LOCKTIME = 0x11
-const PSBT_IN_REQUIRED_TIME_LOCKTIME: u8 = 0x11;
+const PSBT_IN_REQUIRED_TIME_LOCKTIME: u64 = 0x11;
 /// Type: Required Height-based Locktime PSBT_IN_REQUIRED_HEIGHT_LOCKTIME = 0x12
-const PSBT_IN_REQUIRED_HEIGHT_LOCKTIME: u8 = 0x12;
+const PSBT_IN_REQUIRED_HEIGHT_LOCKTIME: u64 = 0x12;
 /// Type: HASH160 preimage PSBT_IN_HASH160 = 0x0c
-const PSBT_IN_HASH160: u8 = 0x0c;
+const PSBT_IN_HASH160: u64 = 0x0c;
 /// Type: HASH256 preimage PSBT_IN_HASH256 = 0x0d
-const PSBT_IN_HASH256: u8 = 0x0d;
+const PSBT_IN_HASH256: u64 = 0x0d;
 /// Type: Taproot Signature in Key Spend PSBT_IN_TAP_KEY_SIG = 0x13
-const PSBT_IN_TAP_KEY_SIG: u8 = 0x13;
+const PSBT_IN_TAP_KEY_SIG: u64 = 0x13;
 /// Type: Taproot Signature in Script Spend PSBT_IN_TAP_SCRIPT_SIG = 0x14
-const PSBT_IN_TAP_SCRIPT_SIG: u8 = 0x14;
+const PSBT_IN_TAP_SCRIPT_SIG: u64 = 0x14;
 /// Type: Taproot Leaf Script PSBT_IN_TAP_LEAF_SCRIPT = 0x14
-const PSBT_IN_TAP_LEAF_SCRIPT: u8 = 0x15;
+const PSBT_IN_TAP_LEAF_SCRIPT: u64 = 0x15;
 /// Type: Taproot Key BIP 32 Derivation Path PSBT_IN_TAP_BIP32_DERIVATION = 0x16
-const PSBT_IN_TAP_BIP32_DERIVATION: u8 = 0x16;
+const PSBT_IN_TAP_BIP32_DERIVATION: u64 = 0x16;
 /// Type: Taproot Internal Key PSBT_IN_TAP_INTERNAL_KEY = 0x17
-const PSBT_IN_TAP_INTERNAL_KEY: u8 = 0x17;
+const PSBT_IN_TAP_INTERNAL_KEY: u64 = 0x17;
 /// Type: Taproot Merkle Root PSBT_IN_TAP_MERKLE_ROOT = 0x18
-const PSBT_IN_TAP_MERKLE_ROOT: u8 = 0x18;
+const PSBT_IN_TAP_MERKLE_ROOT: u64 = 0x18;
 /// Type: Silent Payment Elliptic Curve Diffie-Hellman secret share PSBT_IN_SP_ECDH_SHARE = 0x1d
-const PSBT_IN_SP_ECDH_SHARE: u8 = 0x1d;
+const PSBT_IN_SP_ECDH_SHARE: u64 = 0x1d;
 /// Type: Silent Payment Discrete Logarithm Equality Proof PSBT_IN_SP_DLEQ = 0x1e
-const PSBT_IN_SP_DLEQ: u8 = 0x1e;
+const PSBT_IN_SP_DLEQ: u64 = 0x1e;
 /// Type: Proprietary Use Type PSBT_IN_PROPRIETARY = 0xFC
-const PSBT_IN_PROPRIETARY: u8 = 0xFC;
+const PSBT_IN_PROPRIETARY: u64 = 0xFC;
 
 /// A key-value map for an input of the corresponding index in the unsigned
 /// transaction.