P2QRH:

1.  No need to prefix every element of witness stack with 1 byte compact
    size length

2.  Includes P2TR end-to-end example in Rust (for purpose of comparison with
    P2QRH)

Author: jbride

bip-0360/ref-impl/rust/docs/p2qrh-end-to-end.adoc

@@ -55,8 +55,8 @@ $ b-reg decodescript 206d4ddc0e47d2e8f82cbe2fc2d0d749e7bd3338112cecdc76d8f831ae6
 +
 NOTE:  This script includes a 32-byte x-only public key.
 Subsequently, it is not of standard type P2PK.
-As a standalone script, this script would be considered _non-standard_.  
-However, as the script of a tapleaf, the script is considered _standard_.
+As a standalone script, this script would be considered _non-standard_.
+However, as a tapleaf script, it is considered _standard_.
 Tapscript relaxes many script standardness rules.
 
 . Generate a P2QRH scripPubKey and address given a taptree as defined in link:https://learnmeabitcoin.com/technical/upgrades/taproot/#example-3-script-path-spend-signature[learnmeabitcoin tutorial] :
@@ -67,9 +67,11 @@ $ export BITCOIN_ADDRESS_INFO=$( cargo run --example p2qrh_construction ) \
 
 $ export BITCOIN_NETWORK=regtest \
   && export P2QRH_ADDR=$( echo $BITCOIN_ADDRESS_INFO | jq -r '.bech32m_address' ) \
-  && export FUNDING_SCRIPT_PUBKEY=$( echo $BITCOIN_ADDRESS_INFO | jq -r '.script_pubkey' ) \
+  && export FUNDING_SCRIPT_PUBKEY=$( echo $BITCOIN_ADDRESS_INFO | jq -r '.script_pubkey_hex' ) \
   && echo -en "$P2QRH_ADDR\n$FUNDING_SCRIPT_PUBKEY\n"
 -----
++
+NOTE:  In `regtest`, you can expect a P2QRH address that starts with: `bcrt1r` .
 
 . fund this P2QRH address with the coinbase reward of a newly generated block:
 +
@@ -95,7 +97,7 @@ $ export FUNDING_TX_ID=$( b-reg scantxoutset start '[{"desc": "'''$P2QRH_DESC'''
     && echo $FUNDING_TX_ID
 -----
 
-. Set FUNDIN_UTXO_INDEX env var (used later to correctly identify funding UTXO when generating the spending tx)
+. Set FUNDING_UTXO_INDEX env var (used later to correctly identify funding UTXO when generating the spending tx)
 +
 -----
 $ export FUNDING_UTXO_INDEX=0
@@ -111,7 +113,7 @@ $ export FUNDING_UTXO=$( b-reg getrawtransaction $FUNDING_TX_ID 1 | jq -r '.vout
 == Spend P2QRH UTXO
 
 
-. Determine value (in BTC) of funding utxo:
+. Determine value (in sats) of funding utxo:
 +
 -----
 $ export FUNDING_UTXO_AMOUNT_SATS=$(echo $FUNDING_UTXO | jq -r '.value' | awk '{printf "%.0f", $1 * 100000000}') \

bip-0360/ref-impl/rust/docs/p2tr-end-to-end.adoc

@@ -0,0 +1,192 @@
+:scrollbar:
+:data-uri:
+:toc2:
+:linkattrs:
+
+= P2TR End-to-End Tutorial
+
+:numbered:
+
+This tutorial is inspired from the link:https://learnmeabitcoin.com/technical/upgrades/taproot/#example-3-script-path-spend-signature[script-path-spend-signature] example of the _learnmeabitcoin_ tutorial.
+
+Execute in Bitcoin Core `regtest` mode.
+
+== Pre-reqs
+
+=== Bitcoin Core
+
+TO-DO
+
+=== Shell Environment
+
+. *b-reg* command line alias:
++
+Configure an alias to the `bitcoin-cli` command that connects to your customized bitcoin-core node running in `regtest` mode.
+. *jq*: ensure json parsing utility is installed and available via your $PATH.
+. *awk* : standard utility for all Linux distros (often packaged as `gawk`).
+
+=== Bitcoin Core Wallet
+
+This tutorial assumes that a bitcoin core wallet is available.
+For example, the following would be sufficient:
+
+-----
+$ export W_NAME=regtest \
+        && export WPASS=regtest
+
+$ b-reg -named createwallet \
+    wallet_name=$W_NAME \
+    descriptors=true \
+    passphrase="$WPASS" \
+    load_on_startup=true
+-----
+
+== Fund P2TR UTXO
+
+. View (hard-coded) tapscript used in single leaf taptree:
++
+-----
+$ b-reg decodescript 206d4ddc0e47d2e8f82cbe2fc2d0d749e7bd3338112cecdc76d8f831ae6620dbe0ac | jq -r '.asm'
+
+6d4ddc0e47d2e8f82cbe2fc2d0d749e7bd3338112cecdc76d8f831ae6620dbe0 OP_CHECKSIG
+-----
++
+NOTE:  This script includes a 32-byte x-only public key.
+Subsequently, it is not of standard type P2PK.
+As a standalone script, this script would be considered _non-standard_.  
+However, as a tapleaf script, it is considered _standard_.
+Tapscript relaxes many script standardness rules.
+
+. Generate a P2TR scripPubKey and address given a taptree as defined in link:https://learnmeabitcoin.com/technical/upgrades/taproot/#example-3-script-path-spend-signature[learnmeabitcoin tutorial] :
++
+-----
+$ export BITCOIN_ADDRESS_INFO=$( cargo run --example p2tr_construction ) \
+    && echo $BITCOIN_ADDRESS_INFO | jq -r .
+
+$ export BITCOIN_NETWORK=regtest \
+  && export P2TR_ADDR=$( echo $BITCOIN_ADDRESS_INFO | jq -r '.bech32m_address' ) \
+  && export FUNDING_SCRIPT_PUBKEY=$( echo $BITCOIN_ADDRESS_INFO | jq -r '.script_pubkey_hex' ) \
+  && echo -en "$P2TR_ADDR\n$FUNDING_SCRIPT_PUBKEY\n"
+-----
++
+NOTE: In `regtest`, you can expect a P2TR address that starts with: `bcrt1q` .
+
+. fund this P2TR address with the coinbase reward of a newly generated block:
++
+-----
+$ export COINBASE_REWARD_TX_ID=$( b-reg -named generatetoaddress 1 $P2TR_ADDR 1 | jq -r '.[]' ) \
+    && echo $COINBASE_REWARD_TX_ID
+-----
++
+NOTE:  Sometimes Bitcoin Core does not immediately respond.  If so, wait a few seconds and try the above command again.
+
+. view summary of all txs that have funded P2TR address
++
+-----
+$ export P2TR_DESC=$( b-reg getdescriptorinfo "addr($P2TR_ADDR)" | jq -r '.descriptor' ) \
+    && echo $P2TR_DESC
+$ b-reg scantxoutset start '[{"desc": "'''$P2TR_DESC'''"}]'
+-----
+
+. grab txid of first tx with unspent funds:
++
+-----
+$ export FUNDING_TX_ID=$( b-reg scantxoutset start '[{"desc": "'''$P2TR_DESC'''"}]' | jq -r '.unspents[0].txid' ) \
+    && echo $FUNDING_TX_ID
+-----
+
+. Set FUNDING_UTXO_INDEX env var (used later to correctly identify funding UTXO when generating the spending tx)
++
+-----
+$ export FUNDING_UTXO_INDEX=0
+-----
+
+. view details of funding UTXO to the P2TR address:
++
+-----
+$ export FUNDING_UTXO=$( b-reg getrawtransaction $FUNDING_TX_ID 1 | jq -r '.vout['''$FUNDING_UTXO_INDEX''']' ) \
+    && echo $FUNDING_UTXO | jq -r .
+-----
+
+== Spend P2TR UTXO
+
+
+. Determine value (in sats) of funding utxo:
++
+-----
+$ export FUNDING_UTXO_AMOUNT_SATS=$(echo $FUNDING_UTXO | jq -r '.value' | awk '{printf "%.0f", $1 * 100000000}') \
+    && echo $FUNDING_UTXO_AMOUNT_SATS
+-----
+
+. Referencing the funding tx (via $FUNDING_TX_ID and $FUNDING_UTXO_INDEX), create the spending tx:
++
+-----
+$ export RAW_P2TR_SPEND_TX=$( cargo run --example p2tr_spend | jq -r '.tx_hex' ) \
+    && echo $RAW_P2TR_SPEND_TX
+-----
+
+. Inspect the spending tx:
++
+-----
+$ b-reg decoderawtransaction $RAW_P2TR_SPEND_TX
+-----
+
+. Test standardness of the spending tx by sending to local mempool of p2tr enabled Bitcoin Core:
+
+.. Generate additional blocks.
++
+This is necessary if you have only previously generated 1 block in your bitcoin core.
++
+-----
+$ b-reg -generate 110
+-----
++
+Otherwise, you may see an error from bitcoin core such as the following:
++
+_bad-txns-premature-spend-of-coinbase, tried to spend coinbase at depth 1_
+
+.. Execute:
++
+-----
+$ b-reg testmempoolaccept '["'''$RAW_P2TR_SPEND_TX'''"]'
+-----
+
+. Submit tx:
++
+-----
+$ export P2TR_SPENDING_TX_ID=$( b-reg sendrawtransaction $RAW_P2TR_SPEND_TX ) \
+    && echo $P2TR_SPENDING_TX_ID
+-----
++
+NOTE:  Should return same tx id as was included in $RAW_P2TR_SPEND_TX
+
+== Mine P2TR Spend TX
+
+. View tx in mempool:
++
+-----
+$ b-reg getrawtransaction $P2TR_SPENDING_TX_ID 1
+-----
++
+NOTE:  There will not yet be a field `blockhash` in the response.
+
+. Mine 1 block:
++
+-----
+$ b-reg -generate 1
+-----
+
+. Obtain `blockhash` field of mined tx:
++
+-----
+$ export BLOCK_HASH=$( b-reg getrawtransaction $P2TR_SPENDING_TX_ID 1 | jq -r '.blockhash' ) \
+    && echo $BLOCK_HASH
+-----
+
+. View tx in block:
++
+-----
+$ b-reg getblock $BLOCK_HASH | jq -r .tx
+-----
+
+== TO-DO

bip-0360/ref-impl/rust/examples/p2qrh_construction.rs

@@ -1,21 +1,10 @@
-use bitcoin::taproot::TapNodeHash;
 use p2qrh_ref::create_p2qrh_utxo;
-use p2qrh_ref::data_structures::P2qrhUtxoReturn;
-use bitcoin::hashes::Hash;
-use hex;
-
-fn main() -> P2qrhUtxoReturn {
-    let p2qrh_utxo_return: P2qrhUtxoReturn = p2qrh_script_path_utxo_construction();
-    p2qrh_utxo_return
-}
+use p2qrh_ref::data_structures::UtxoReturn;
 
 // Inspired by:  https://learnmeabitcoin.com/technical/upgrades/taproot/#example-3-script-path-spend-signature
-fn p2qrh_script_path_utxo_construction() -> P2qrhUtxoReturn {
-
-    let merkle_root_bytes= hex::decode("858dfe26a3dd48a2c1fcee1d631f0aadf6a61135fc51f75758e945bca534ef16").unwrap();
-    let merkle_root: TapNodeHash = TapNodeHash::from_byte_array(merkle_root_bytes.try_into().unwrap());
-
-    let p2qrh_utxo_return: P2qrhUtxoReturn = create_p2qrh_utxo(merkle_root);
-
-    return p2qrh_utxo_return;
+fn main() -> UtxoReturn {
+    
+    let merkle_root_hex = "858dfe26a3dd48a2c1fcee1d631f0aadf6a61135fc51f75758e945bca534ef16".to_string();
+    let p2qrh_utxo_return: UtxoReturn = create_p2qrh_utxo(merkle_root_hex);
+    p2qrh_utxo_return
 }

bip-0360/ref-impl/rust/examples/p2qrh_spend.rs

@@ -1,11 +1,11 @@
-use p2qrh_ref::{ p2qrh_to_p2wpkh_tx };
+use p2qrh_ref::{ pay_to_p2wpkh_tx };
 
-use p2qrh_ref::data_structures::P2qrhSpendDetails;
+use p2qrh_ref::data_structures::SpendDetails;
 use std::env;
 use log::{info, error};
 
 // Inspired by:  https://learnmeabitcoin.com/technical/upgrades/taproot/#example-3-script-path-spend-signature
-fn main() -> P2qrhSpendDetails {
+fn main() -> SpendDetails {
 
     let _ = env_logger::try_init(); // Use try_init to avoid reinitialization error
 
@@ -47,10 +47,12 @@ fn main() -> P2qrhSpendDetails {
             std::process::exit(1);
         });
 
-    // Modified from learnmeabitcoin example
-    // Changed from c0 to c1 control byte to reflect p2qrh specification:  The parity bit of the control byte is always 1 since P2QRH does not have a key-spend path.
+    // P2QRH control block does not include internal pubkey.
+    // (P2TR internal pubkey is used to verify that the pub key and merkle root can be combined to match the tweaked pub key in ScriptPubKey).
+    // P2QRH leaf version will always be c1: The parity bit of the control byte is always 1 since P2QRH does not have a key-spend path.
+    // In this tutorial, there is only a single leaf in the taptree; thus no script path.
     let p2qrh_control_block_bytes: Vec<u8> =
-        hex::decode("c1924c163b385af7093440184af6fd6244936d1288cbb41cc3812286d3f83a3329").unwrap();
+        hex::decode("c1").unwrap();
     info!("P2QRH control block size: {}", p2qrh_control_block_bytes.len());
 
     let leaf_script_priv_key_bytes: Vec<u8> = hex::decode("9b8de5d7f20a8ebb026a82babac3aa47a008debbfde5348962b2c46520bd5189").unwrap();
@@ -59,25 +61,26 @@ fn main() -> P2qrhSpendDetails {
     let leaf_script_bytes: Vec<u8> =
         hex::decode("206d4ddc0e47d2e8f82cbe2fc2d0d749e7bd3338112cecdc76d8f831ae6620dbe0ac").unwrap();
 
-    let leaf_script_pubkey_hash_bytes: Vec<u8> = hex::decode("0de745dc58d8e62e6f47bde30cd5804a82016f9e").unwrap();
+    // https://learnmeabitcoin.com/explorer/tx/797505b104b5fb840931c115ea35d445eb1f64c9279bf23aa5bb4c3d779da0c2#outputs
+    let spend_output_pubkey_bytes: Vec<u8> = hex::decode("0de745dc58d8e62e6f47bde30cd5804a82016f9e").unwrap();
 
     // OUTPUT_AMOUNT_SATS env var is optional. Default is FUNDING_UTXO_AMOUNT_SATS - 5000 sats
-    let output_amount_sats: u64 = env::var("OUTPUT_AMOUNT_SATS")
+    let spend_output_amount_sats: u64 = env::var("OUTPUT_AMOUNT_SATS")
         .ok()
         .and_then(|s| s.parse::<u64>().ok())
         .unwrap_or(funding_utxo_amount_sats.saturating_sub(5000));
 
 
-    let result: P2qrhSpendDetails = p2qrh_to_p2wpkh_tx(
+    let result: SpendDetails = pay_to_p2wpkh_tx(
         funding_tx_id_bytes,
         funding_utxo_index,
         funding_utxo_amount_sats,
         funding_script_pubkey_bytes,
         p2qrh_control_block_bytes,
-        leaf_script_pubkey_hash_bytes,
         leaf_script_bytes,
         leaf_script_priv_key_bytes,
-        output_amount_sats
+        spend_output_pubkey_bytes,
+        spend_output_amount_sats
     );
 
     return result;

bip-0360/ref-impl/rust/examples/p2tr_construction.rs

@@ -0,0 +1,13 @@
+
+use p2qrh_ref::create_p2tr_utxo;
+use p2qrh_ref::data_structures::UtxoReturn;
+
+// Inspired by:  https://learnmeabitcoin.com/technical/upgrades/taproot/#example-3-script-path-spend-signature
+fn main() -> UtxoReturn {
+    
+    let merkle_root_hex = "858dfe26a3dd48a2c1fcee1d631f0aadf6a61135fc51f75758e945bca534ef16".to_string();
+    let internal_pubkey_hex = "924c163b385af7093440184af6fd6244936d1288cbb41cc3812286d3f83a3329".to_string();
+    
+    let p2tr_utxo_return: UtxoReturn = create_p2tr_utxo(merkle_root_hex, internal_pubkey_hex);
+    p2tr_utxo_return
+}