#!/usr/bin/env python3
# Copyright (c) 2024-present The Bitcoin Core developers
# Distributed under the MIT software license, see the accompanying
# file COPYING or http://www.opensource.org/licenses/mit-license.php.
"""Tool to convert a compact-serialized UTXO set to a SQLite3 database.
The input UTXO set can be generated by Bitcoin Core with the `dumptxoutset` RPC:
$ bitcoin-cli dumptxoutset ~/utxos.dat latest
The created database contains a table `utxos` with the following schema:
(txid TEXT, vout INT, value INT, coinbase INT, height INT, scriptpubkey TEXT)
"""
import argparse
import os
import sqlite3
import sys
import time
UTXO_DUMP_MAGIC = b'utxo\xff'
UTXO_DUMP_VERSION = 2
NET_MAGIC_BYTES = {
b"\xf9\xbe\xb4\xd9": "Mainnet",
b"\x0a\x03\xcf\x40": "Signet",
b"\x0b\x11\x09\x07": "Testnet3",
b"\x1c\x16\x3f\x28": "Testnet4",
b"\xfa\xbf\xb5\xda": "Regtest",
}
def read_varint(f):
"""Equivalent of `ReadVarInt()` (see serialization module)."""
n = 0
while True:
dat = f.read(1)[0]
n = (n << 7) | (dat & 0x7f)
if (dat & 0x80) > 0:
n += 1
else:
return n
def read_compactsize(f):
"""Equivalent of `ReadCompactSize()` (see serialization module)."""
n = f.read(1)[0]
if n == 253:
n = int.from_bytes(f.read(2), "little")
elif n == 254:
n = int.from_bytes(f.read(4), "little")
elif n == 255:
n = int.from_bytes(f.read(8), "little")
return n
def decompress_amount(x):
"""Equivalent of `DecompressAmount()` (see compressor module)."""
if x == 0:
return 0
x -= 1
e = x % 10
x //= 10
n = 0
if e < 9:
d = (x % 9) + 1
x //= 9
n = x * 10 + d
else:
n = x + 1
while e > 0:
n *= 10
e -= 1
return n
def decompress_script(f):
"""Equivalent of `DecompressScript()` (see compressor module)."""
size = read_varint(f) # sizes 0-5 encode compressed script types
if size == 0: # P2PKH
return bytes([0x76, 0xa9, 20]) + f.read(20) + bytes([0x88, 0xac])
elif size == 1: # P2SH
return bytes([0xa9, 20]) + f.read(20) + bytes([0x87])
elif size in (2, 3): # P2PK (compressed)
return bytes([33, size]) + f.read(32) + bytes([0xac])
elif size in (4, 5): # P2PK (uncompressed)
compressed_pubkey = bytes([size - 2]) + f.read(32)
return bytes([65]) + decompress_pubkey(compressed_pubkey) + bytes([0xac])
else: # others (bare multisig, segwit etc.)
size -= 6
assert size <= 10000, f"too long script with size {size}"
return f.read(size)
def decompress_pubkey(compressed_pubkey):
"""Decompress pubkey by calculating y = sqrt(x^3 + 7) % p
(see functions `secp256k1_eckey_pubkey_parse` and `secp256k1_ge_set_xo_var`).
"""
P = 2**256 - 2**32 - 977 # secp256k1 field size
assert len(compressed_pubkey) == 33 and compressed_pubkey[0] in (2, 3)
x = int.from_bytes(compressed_pubkey[1:], 'big')
rhs = (x**3 + 7) % P
y = pow(rhs, (P + 1)//4, P) # get sqrt using Tonelli-Shanks algorithm (for p % 4 = 3)
assert pow(y, 2, P) == rhs, f"pubkey is not on curve ({compressed_pubkey.hex()})"
tag_is_odd = compressed_pubkey[0] == 3
y_is_odd = (y & 1) == 1
if tag_is_odd != y_is_odd: # fix parity (even/odd) if necessary
y = P - y
return bytes([4]) + x.to_bytes(32, 'big') + y.to_bytes(32, 'big')
def main():
parser = argparse.ArgumentParser(description=__doc__, formatter_class=argparse.RawDescriptionHelpFormatter)
parser.add_argument('infile', help='filename of compact-serialized UTXO set (input)')
parser.add_argument('outfile', help='filename of created SQLite3 database (output)')
parser.add_argument('-v', '--verbose', action='store_true', help='show details about each UTXO')
args = parser.parse_args()
if not os.path.exists(args.infile):
print(f"Error: provided input file '{args.infile}' doesn't exist.")
sys.exit(1)
if os.path.exists(args.outfile):
print(f"Error: provided output file '{args.outfile}' already exists.")
sys.exit(1)
# create database table
con = sqlite3.connect(args.outfile)
con.execute("CREATE TABLE utxos(txid TEXT, vout INT, value INT, coinbase INT, height INT, scriptpubkey TEXT)")
# read metadata (magic bytes, version, network magic, block hash, UTXO count)
f = open(args.infile, 'rb')
magic_bytes = f.read(5)
version = int.from_bytes(f.read(2), 'little')
network_magic = f.read(4)
block_hash = f.read(32)
num_utxos = int.from_bytes(f.read(8), 'little')
if magic_bytes != UTXO_DUMP_MAGIC:
print(f"Error: provided input file '{args.infile}' is not an UTXO dump.")
sys.exit(1)
if version != UTXO_DUMP_VERSION:
print(f"Error: provided input file '{args.infile}' has unknown UTXO dump version {version} "
f"(only version {UTXO_DUMP_VERSION} supported)")
sys.exit(1)
network_string = NET_MAGIC_BYTES.get(network_magic, f"unknown network ({network_magic.hex()})")
print(f"UTXO Snapshot for {network_string} at block hash "
f"{block_hash[::-1].hex()[:32]}..., contains {num_utxos} coins")
start_time = time.time()
write_batch = []
coins_per_hash_left = 0
prevout_hash = None
max_height = 0
for coin_idx in range(1, num_utxos+1):
# read key (COutPoint)
if coins_per_hash_left == 0: # read next prevout hash
prevout_hash = f.read(32)[::-1].hex()
coins_per_hash_left = read_compactsize(f)
prevout_index = read_compactsize(f)
# read value (Coin)
code = read_varint(f)
height = code >> 1
is_coinbase = code & 1
amount = decompress_amount(read_varint(f))
scriptpubkey = decompress_script(f).hex()
write_batch.append((prevout_hash, prevout_index, amount, is_coinbase, height, scriptpubkey))
if height > max_height:
max_height = height
coins_per_hash_left -= 1
if args.verbose:
print(f"Coin {coin_idx}/{num_utxos}:")
print(f" prevout = {prevout_hash}:{prevout_index}")
print(f" amount = {amount}, height = {height}, coinbase = {is_coinbase}")
print(f" scriptPubKey = {scriptpubkey}\n")
if coin_idx % (16*1024) == 0 or coin_idx == num_utxos:
# write utxo batch to database
con.executemany("INSERT INTO utxos VALUES(?, ?, ?, ?, ?, ?)", write_batch)
con.commit()
write_batch.clear()
if coin_idx % (1024*1024) == 0:
elapsed = time.time() - start_time
print(f"{coin_idx} coins converted [{coin_idx/num_utxos*100:.2f}%], " +
f"{elapsed:.3f}s passed since start")
con.close()
print(f"TOTAL: {num_utxos} coins written to {args.outfile}, snapshot height is {max_height}.")
if f.read(1) != b'': # EOF should be reached by now
print(f"WARNING: input file {args.infile} has not reached EOF yet!")
sys.exit(1)
if __name__ == '__main__':
main()