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feature_block.py
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feature_block.py
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#!/usr/bin/env python3
# Copyright (c) 2015-2018 The Bitcoin Core developers
# Distributed under the MIT software license, see the accompanying
# file COPYING or http://www.opensource.org/licenses/mit-license.php.
"""Test block processing."""
import copy
import struct
import time
from test_framework.blocktools import create_block, create_coinbase, create_tx_with_script, get_legacy_sigopcount_block
from test_framework.key import CECKey
from test_framework.messages import (
CBlock,
COIN,
COutPoint,
CTransaction,
CTxIn,
CTxOut,
MAX_BLOCK_BASE_SIZE,
uint256_from_compact,
uint256_from_str,
)
from test_framework.mininode import P2PDataStore
from test_framework.script import (
CScript,
MAX_SCRIPT_ELEMENT_SIZE,
OP_2DUP,
OP_CHECKMULTISIG,
OP_CHECKMULTISIGVERIFY,
OP_CHECKSIG,
OP_CHECKSIGVERIFY,
OP_ELSE,
OP_ENDIF,
OP_EQUAL,
OP_DROP,
OP_FALSE,
OP_HASH160,
OP_IF,
OP_INVALIDOPCODE,
OP_RETURN,
OP_TRUE,
SIGHASH_ALL,
SignatureHash,
hash160,
)
from test_framework.test_framework import BitcoinTestFramework
from test_framework.util import assert_equal
MAX_BLOCK_SIGOPS = 20000
# Use this class for tests that require behavior other than normal "mininode" behavior.
# For now, it is used to serialize a bloated varint (b64).
class CBrokenBlock(CBlock):
def initialize(self, base_block):
self.vtx = copy.deepcopy(base_block.vtx)
self.hashMerkleRoot = self.calc_merkle_root()
def serialize(self, with_witness=False):
r = b""
r += super(CBlock, self).serialize()
r += struct.pack("<BQ", 255, len(self.vtx))
for tx in self.vtx:
if with_witness:
r += tx.serialize_with_witness()
else:
r += tx.serialize_without_witness()
return r
def normal_serialize(self):
return super().serialize()
class FullBlockTest(BitcoinTestFramework):
def set_test_params(self):
self.num_nodes = 1
self.setup_clean_chain = True
self.extra_args = [[]]
def run_test(self):
node = self.nodes[0] # convenience reference to the node
self.bootstrap_p2p() # Add one p2p connection to the node
self.block_heights = {}
self.coinbase_key = CECKey()
self.coinbase_key.set_secretbytes(b"horsebattery")
self.coinbase_pubkey = self.coinbase_key.get_pubkey()
self.tip = None
self.blocks = {}
self.genesis_hash = int(self.nodes[0].getbestblockhash(), 16)
self.block_heights[self.genesis_hash] = 0
self.spendable_outputs = []
# Create a new block
b0 = self.next_block(0)
self.save_spendable_output()
self.sync_blocks([b0])
# Allow the block to mature
blocks = []
for i in range(99):
blocks.append(self.next_block(5000 + i))
self.save_spendable_output()
self.sync_blocks(blocks)
# collect spendable outputs now to avoid cluttering the code later on
out = []
for i in range(33):
out.append(self.get_spendable_output())
# Start by building a couple of blocks on top (which output is spent is
# in parentheses):
# genesis -> b1 (0) -> b2 (1)
b1 = self.next_block(1, spend=out[0])
self.save_spendable_output()
b2 = self.next_block(2, spend=out[1])
self.save_spendable_output()
self.sync_blocks([b1, b2])
# Fork like this:
#
# genesis -> b1 (0) -> b2 (1)
# \-> b3 (1)
#
# Nothing should happen at this point. We saw b2 first so it takes priority.
self.log.info("Don't reorg to a chain of the same length")
self.move_tip(1)
b3 = self.next_block(3, spend=out[1])
txout_b3 = b3.vtx[1]
self.sync_blocks([b3], False)
# Now we add another block to make the alternative chain longer.
#
# genesis -> b1 (0) -> b2 (1)
# \-> b3 (1) -> b4 (2)
self.log.info("Reorg to a longer chain")
b4 = self.next_block(4, spend=out[2])
self.sync_blocks([b4])
# ... and back to the first chain.
# genesis -> b1 (0) -> b2 (1) -> b5 (2) -> b6 (3)
# \-> b3 (1) -> b4 (2)
self.move_tip(2)
b5 = self.next_block(5, spend=out[2])
self.save_spendable_output()
self.sync_blocks([b5], False)
self.log.info("Reorg back to the original chain")
b6 = self.next_block(6, spend=out[3])
self.sync_blocks([b6], True)
# Try to create a fork that double-spends
# genesis -> b1 (0) -> b2 (1) -> b5 (2) -> b6 (3)
# \-> b7 (2) -> b8 (4)
# \-> b3 (1) -> b4 (2)
self.log.info("Reject a chain with a double spend, even if it is longer")
self.move_tip(5)
b7 = self.next_block(7, spend=out[2])
self.sync_blocks([b7], False)
b8 = self.next_block(8, spend=out[4])
self.sync_blocks([b8], False, reconnect=True)
# Try to create a block that has too much fee
# genesis -> b1 (0) -> b2 (1) -> b5 (2) -> b6 (3)
# \-> b9 (4)
# \-> b3 (1) -> b4 (2)
self.log.info("Reject a block where the miner creates too much coinbase reward")
self.move_tip(6)
b9 = self.next_block(9, spend=out[4], additional_coinbase_value=1)
self.sync_blocks([b9], success=False, reject_reason='bad-cb-amount', reconnect=True)
# Create a fork that ends in a block with too much fee (the one that causes the reorg)
# genesis -> b1 (0) -> b2 (1) -> b5 (2) -> b6 (3)
# \-> b10 (3) -> b11 (4)
# \-> b3 (1) -> b4 (2)
self.log.info("Reject a chain where the miner creates too much coinbase reward, even if the chain is longer")
self.move_tip(5)
b10 = self.next_block(10, spend=out[3])
self.sync_blocks([b10], False)
b11 = self.next_block(11, spend=out[4], additional_coinbase_value=1)
self.sync_blocks([b11], success=False, reject_reason='bad-cb-amount', reconnect=True)
# Try again, but with a valid fork first
# genesis -> b1 (0) -> b2 (1) -> b5 (2) -> b6 (3)
# \-> b12 (3) -> b13 (4) -> b14 (5)
# \-> b3 (1) -> b4 (2)
self.log.info("Reject a chain where the miner creates too much coinbase reward, even if the chain is longer (on a forked chain)")
self.move_tip(5)
b12 = self.next_block(12, spend=out[3])
self.save_spendable_output()
b13 = self.next_block(13, spend=out[4])
self.save_spendable_output()
b14 = self.next_block(14, spend=out[5], additional_coinbase_value=1)
self.sync_blocks([b12, b13, b14], success=False, reject_reason='bad-cb-amount', reconnect=True)
# New tip should be b13.
assert_equal(node.getbestblockhash(), b13.hash)
# Add a block with MAX_BLOCK_SIGOPS and one with one more sigop
# genesis -> b1 (0) -> b2 (1) -> b5 (2) -> b6 (3)
# \-> b12 (3) -> b13 (4) -> b15 (5) -> b16 (6)
# \-> b3 (1) -> b4 (2)
self.log.info("Accept a block with lots of checksigs")
lots_of_checksigs = CScript([OP_CHECKSIG] * (MAX_BLOCK_SIGOPS - 1))
self.move_tip(13)
b15 = self.next_block(15, spend=out[5], script=lots_of_checksigs)
self.save_spendable_output()
self.sync_blocks([b15], True)
self.log.info("Reject a block with too many checksigs")
too_many_checksigs = CScript([OP_CHECKSIG] * (MAX_BLOCK_SIGOPS))
b16 = self.next_block(16, spend=out[6], script=too_many_checksigs)
self.sync_blocks([b16], success=False, reject_reason='bad-blk-sigops', reconnect=True)
# Attempt to spend a transaction created on a different fork
# genesis -> b1 (0) -> b2 (1) -> b5 (2) -> b6 (3)
# \-> b12 (3) -> b13 (4) -> b15 (5) -> b17 (b3.vtx[1])
# \-> b3 (1) -> b4 (2)
self.log.info("Reject a block with a spend from a re-org'ed out tx")
self.move_tip(15)
b17 = self.next_block(17, spend=txout_b3)
self.sync_blocks([b17], success=False, reject_reason='bad-txns-inputs-missingorspent', reconnect=True)
# Attempt to spend a transaction created on a different fork (on a fork this time)
# genesis -> b1 (0) -> b2 (1) -> b5 (2) -> b6 (3)
# \-> b12 (3) -> b13 (4) -> b15 (5)
# \-> b18 (b3.vtx[1]) -> b19 (6)
# \-> b3 (1) -> b4 (2)
self.log.info("Reject a block with a spend from a re-org'ed out tx (on a forked chain)")
self.move_tip(13)
b18 = self.next_block(18, spend=txout_b3)
self.sync_blocks([b18], False)
b19 = self.next_block(19, spend=out[6])
self.sync_blocks([b19], success=False, reject_reason='bad-txns-inputs-missingorspent', reconnect=True)
# Attempt to spend a coinbase at depth too low
# genesis -> b1 (0) -> b2 (1) -> b5 (2) -> b6 (3)
# \-> b12 (3) -> b13 (4) -> b15 (5) -> b20 (7)
# \-> b3 (1) -> b4 (2)
self.log.info("Reject a block spending an immature coinbase.")
self.move_tip(15)
b20 = self.next_block(20, spend=out[7])
self.sync_blocks([b20], success=False, reject_reason='bad-txns-premature-spend-of-coinbase')
# Attempt to spend a coinbase at depth too low (on a fork this time)
# genesis -> b1 (0) -> b2 (1) -> b5 (2) -> b6 (3)
# \-> b12 (3) -> b13 (4) -> b15 (5)
# \-> b21 (6) -> b22 (5)
# \-> b3 (1) -> b4 (2)
self.log.info("Reject a block spending an immature coinbase (on a forked chain)")
self.move_tip(13)
b21 = self.next_block(21, spend=out[6])
self.sync_blocks([b21], False)
b22 = self.next_block(22, spend=out[5])
self.sync_blocks([b22], success=False, reject_reason='bad-txns-premature-spend-of-coinbase')
# Create a block on either side of MAX_BLOCK_BASE_SIZE and make sure its accepted/rejected
# genesis -> b1 (0) -> b2 (1) -> b5 (2) -> b6 (3)
# \-> b12 (3) -> b13 (4) -> b15 (5) -> b23 (6)
# \-> b24 (6) -> b25 (7)
# \-> b3 (1) -> b4 (2)
self.log.info("Accept a block of size MAX_BLOCK_BASE_SIZE")
self.move_tip(15)
b23 = self.next_block(23, spend=out[6])
tx = CTransaction()
script_length = MAX_BLOCK_BASE_SIZE - len(b23.serialize()) - 69
script_output = CScript([b'\x00' * script_length])
tx.vout.append(CTxOut(0, script_output))
tx.vin.append(CTxIn(COutPoint(b23.vtx[1].sha256, 0)))
b23 = self.update_block(23, [tx])
# Make sure the math above worked out to produce a max-sized block
assert_equal(len(b23.serialize()), MAX_BLOCK_BASE_SIZE)
self.sync_blocks([b23], True)
self.save_spendable_output()
self.log.info("Reject a block of size MAX_BLOCK_BASE_SIZE + 1")
self.move_tip(15)
b24 = self.next_block(24, spend=out[6])
script_length = MAX_BLOCK_BASE_SIZE - len(b24.serialize()) - 69
script_output = CScript([b'\x00' * (script_length + 1)])
tx.vout = [CTxOut(0, script_output)]
b24 = self.update_block(24, [tx])
assert_equal(len(b24.serialize()), MAX_BLOCK_BASE_SIZE + 1)
self.sync_blocks([b24], success=False, reject_reason='bad-blk-length', reconnect=True)
b25 = self.next_block(25, spend=out[7])
self.sync_blocks([b25], False)
# Create blocks with a coinbase input script size out of range
# genesis -> b1 (0) -> b2 (1) -> b5 (2) -> b6 (3)
# \-> b12 (3) -> b13 (4) -> b15 (5) -> b23 (6) -> b30 (7)
# \-> ... (6) -> ... (7)
# \-> b3 (1) -> b4 (2)
self.log.info("Reject a block with coinbase input script size out of range")
self.move_tip(15)
b26 = self.next_block(26, spend=out[6])
b26.vtx[0].vin[0].scriptSig = b'\x00'
b26.vtx[0].rehash()
# update_block causes the merkle root to get updated, even with no new
# transactions, and updates the required state.
b26 = self.update_block(26, [])
self.sync_blocks([b26], success=False, reject_reason='bad-cb-length', reconnect=True)
# Extend the b26 chain to make sure bitcoind isn't accepting b26
b27 = self.next_block(27, spend=out[7])
self.sync_blocks([b27], False)
# Now try a too-large-coinbase script
self.move_tip(15)
b28 = self.next_block(28, spend=out[6])
b28.vtx[0].vin[0].scriptSig = b'\x00' * 101
b28.vtx[0].rehash()
b28 = self.update_block(28, [])
self.sync_blocks([b28], success=False, reject_reason='bad-cb-length', reconnect=True)
# Extend the b28 chain to make sure bitcoind isn't accepting b28
b29 = self.next_block(29, spend=out[7])
self.sync_blocks([b29], False)
# b30 has a max-sized coinbase scriptSig.
self.move_tip(23)
b30 = self.next_block(30)
b30.vtx[0].vin[0].scriptSig = b'\x00' * 100
b30.vtx[0].rehash()
b30 = self.update_block(30, [])
self.sync_blocks([b30], True)
self.save_spendable_output()
# b31 - b35 - check sigops of OP_CHECKMULTISIG / OP_CHECKMULTISIGVERIFY / OP_CHECKSIGVERIFY
#
# genesis -> ... -> b30 (7) -> b31 (8) -> b33 (9) -> b35 (10)
# \-> b36 (11)
# \-> b34 (10)
# \-> b32 (9)
#
# MULTISIG: each op code counts as 20 sigops. To create the edge case, pack another 19 sigops at the end.
self.log.info("Accept a block with the max number of OP_CHECKMULTISIG sigops")
lots_of_multisigs = CScript([OP_CHECKMULTISIG] * ((MAX_BLOCK_SIGOPS - 1) // 20) + [OP_CHECKSIG] * 19)
b31 = self.next_block(31, spend=out[8], script=lots_of_multisigs)
assert_equal(get_legacy_sigopcount_block(b31), MAX_BLOCK_SIGOPS)
self.sync_blocks([b31], True)
self.save_spendable_output()
# this goes over the limit because the coinbase has one sigop
self.log.info("Reject a block with too many OP_CHECKMULTISIG sigops")
too_many_multisigs = CScript([OP_CHECKMULTISIG] * (MAX_BLOCK_SIGOPS // 20))
b32 = self.next_block(32, spend=out[9], script=too_many_multisigs)
assert_equal(get_legacy_sigopcount_block(b32), MAX_BLOCK_SIGOPS + 1)
self.sync_blocks([b32], success=False, reject_reason='bad-blk-sigops', reconnect=True)
# CHECKMULTISIGVERIFY
self.log.info("Accept a block with the max number of OP_CHECKMULTISIGVERIFY sigops")
self.move_tip(31)
lots_of_multisigs = CScript([OP_CHECKMULTISIGVERIFY] * ((MAX_BLOCK_SIGOPS - 1) // 20) + [OP_CHECKSIG] * 19)
b33 = self.next_block(33, spend=out[9], script=lots_of_multisigs)
self.sync_blocks([b33], True)
self.save_spendable_output()
self.log.info("Reject a block with too many OP_CHECKMULTISIGVERIFY sigops")
too_many_multisigs = CScript([OP_CHECKMULTISIGVERIFY] * (MAX_BLOCK_SIGOPS // 20))
b34 = self.next_block(34, spend=out[10], script=too_many_multisigs)
self.sync_blocks([b34], success=False, reject_reason='bad-blk-sigops', reconnect=True)
# CHECKSIGVERIFY
self.log.info("Accept a block with the max number of OP_CHECKSIGVERIFY sigops")
self.move_tip(33)
lots_of_checksigs = CScript([OP_CHECKSIGVERIFY] * (MAX_BLOCK_SIGOPS - 1))
b35 = self.next_block(35, spend=out[10], script=lots_of_checksigs)
self.sync_blocks([b35], True)
self.save_spendable_output()
self.log.info("Reject a block with too many OP_CHECKSIGVERIFY sigops")
too_many_checksigs = CScript([OP_CHECKSIGVERIFY] * (MAX_BLOCK_SIGOPS))
b36 = self.next_block(36, spend=out[11], script=too_many_checksigs)
self.sync_blocks([b36], success=False, reject_reason='bad-blk-sigops', reconnect=True)
# Check spending of a transaction in a block which failed to connect
#
# b6 (3)
# b12 (3) -> b13 (4) -> b15 (5) -> b23 (6) -> b30 (7) -> b31 (8) -> b33 (9) -> b35 (10)
# \-> b37 (11)
# \-> b38 (11/37)
#
# save 37's spendable output, but then double-spend out11 to invalidate the block
self.log.info("Reject a block spending transaction from a block which failed to connect")
self.move_tip(35)
b37 = self.next_block(37, spend=out[11])
txout_b37 = b37.vtx[1]
tx = self.create_and_sign_transaction(out[11], 0)
b37 = self.update_block(37, [tx])
self.sync_blocks([b37], success=False, reject_reason='bad-txns-inputs-missingorspent', reconnect=True)
# attempt to spend b37's first non-coinbase tx, at which point b37 was still considered valid
self.move_tip(35)
b38 = self.next_block(38, spend=txout_b37)
self.sync_blocks([b38], success=False, reject_reason='bad-txns-inputs-missingorspent', reconnect=True)
# Check P2SH SigOp counting
#
#
# 13 (4) -> b15 (5) -> b23 (6) -> b30 (7) -> b31 (8) -> b33 (9) -> b35 (10) -> b39 (11) -> b41 (12)
# \-> b40 (12)
#
# b39 - create some P2SH outputs that will require 6 sigops to spend:
#
# redeem_script = COINBASE_PUBKEY, (OP_2DUP+OP_CHECKSIGVERIFY) * 5, OP_CHECKSIG
# p2sh_script = OP_HASH160, ripemd160(sha256(script)), OP_EQUAL
#
self.log.info("Check P2SH SIGOPS are correctly counted")
self.move_tip(35)
b39 = self.next_block(39)
b39_outputs = 0
b39_sigops_per_output = 6
# Build the redeem script, hash it, use hash to create the p2sh script
redeem_script = CScript([self.coinbase_pubkey] + [OP_2DUP, OP_CHECKSIGVERIFY] * 5 + [OP_CHECKSIG])
redeem_script_hash = hash160(redeem_script)
p2sh_script = CScript([OP_HASH160, redeem_script_hash, OP_EQUAL])
# Create a transaction that spends one satoshi to the p2sh_script, the rest to OP_TRUE
# This must be signed because it is spending a coinbase
spend = out[11]
tx = self.create_tx(spend, 0, 1, p2sh_script)
tx.vout.append(CTxOut(spend.vout[0].nValue - 1, CScript([OP_TRUE])))
self.sign_tx(tx, spend)
tx.rehash()
b39 = self.update_block(39, [tx])
b39_outputs += 1
# Until block is full, add tx's with 1 satoshi to p2sh_script, the rest to OP_TRUE
tx_new = None
tx_last = tx
total_size = len(b39.serialize())
while(total_size < MAX_BLOCK_BASE_SIZE):
tx_new = self.create_tx(tx_last, 1, 1, p2sh_script)
tx_new.vout.append(CTxOut(tx_last.vout[1].nValue - 1, CScript([OP_TRUE])))
tx_new.rehash()
total_size += len(tx_new.serialize())
if total_size >= MAX_BLOCK_BASE_SIZE:
break
b39.vtx.append(tx_new) # add tx to block
tx_last = tx_new
b39_outputs += 1
b39 = self.update_block(39, [])
self.sync_blocks([b39], True)
self.save_spendable_output()
# Test sigops in P2SH redeem scripts
#
# b40 creates 3333 tx's spending the 6-sigop P2SH outputs from b39 for a total of 19998 sigops.
# The first tx has one sigop and then at the end we add 2 more to put us just over the max.
#
# b41 does the same, less one, so it has the maximum sigops permitted.
#
self.log.info("Reject a block with too many P2SH sigops")
self.move_tip(39)
b40 = self.next_block(40, spend=out[12])
sigops = get_legacy_sigopcount_block(b40)
numTxes = (MAX_BLOCK_SIGOPS - sigops) // b39_sigops_per_output
assert_equal(numTxes <= b39_outputs, True)
lastOutpoint = COutPoint(b40.vtx[1].sha256, 0)
new_txs = []
for i in range(1, numTxes + 1):
tx = CTransaction()
tx.vout.append(CTxOut(1, CScript([OP_TRUE])))
tx.vin.append(CTxIn(lastOutpoint, b''))
# second input is corresponding P2SH output from b39
tx.vin.append(CTxIn(COutPoint(b39.vtx[i].sha256, 0), b''))
# Note: must pass the redeem_script (not p2sh_script) to the signature hash function
(sighash, err) = SignatureHash(redeem_script, tx, 1, SIGHASH_ALL)
sig = self.coinbase_key.sign(sighash) + bytes(bytearray([SIGHASH_ALL]))
scriptSig = CScript([sig, redeem_script])
tx.vin[1].scriptSig = scriptSig
tx.rehash()
new_txs.append(tx)
lastOutpoint = COutPoint(tx.sha256, 0)
b40_sigops_to_fill = MAX_BLOCK_SIGOPS - (numTxes * b39_sigops_per_output + sigops) + 1
tx = CTransaction()
tx.vin.append(CTxIn(lastOutpoint, b''))
tx.vout.append(CTxOut(1, CScript([OP_CHECKSIG] * b40_sigops_to_fill)))
tx.rehash()
new_txs.append(tx)
self.update_block(40, new_txs)
self.sync_blocks([b40], success=False, reject_reason='bad-blk-sigops', reconnect=True)
# same as b40, but one less sigop
self.log.info("Accept a block with the max number of P2SH sigops")
self.move_tip(39)
b41 = self.next_block(41, spend=None)
self.update_block(41, b40.vtx[1:-1])
b41_sigops_to_fill = b40_sigops_to_fill - 1
tx = CTransaction()
tx.vin.append(CTxIn(lastOutpoint, b''))
tx.vout.append(CTxOut(1, CScript([OP_CHECKSIG] * b41_sigops_to_fill)))
tx.rehash()
self.update_block(41, [tx])
self.sync_blocks([b41], True)
# Fork off of b39 to create a constant base again
#
# b23 (6) -> b30 (7) -> b31 (8) -> b33 (9) -> b35 (10) -> b39 (11) -> b42 (12) -> b43 (13)
# \-> b41 (12)
#
self.move_tip(39)
b42 = self.next_block(42, spend=out[12])
self.save_spendable_output()
b43 = self.next_block(43, spend=out[13])
self.save_spendable_output()
self.sync_blocks([b42, b43], True)
# Test a number of really invalid scenarios
#
# -> b31 (8) -> b33 (9) -> b35 (10) -> b39 (11) -> b42 (12) -> b43 (13) -> b44 (14)
# \-> ??? (15)
# The next few blocks are going to be created "by hand" since they'll do funky things, such as having
# the first transaction be non-coinbase, etc. The purpose of b44 is to make sure this works.
self.log.info("Build block 44 manually")
height = self.block_heights[self.tip.sha256] + 1
coinbase = create_coinbase(height, self.coinbase_pubkey)
b44 = CBlock()
b44.nTime = self.tip.nTime + 1
b44.hashPrevBlock = self.tip.sha256
b44.nBits = 0x207fffff
b44.vtx.append(coinbase)
b44.hashMerkleRoot = b44.calc_merkle_root()
b44.solve()
self.tip = b44
self.block_heights[b44.sha256] = height
self.blocks[44] = b44
self.sync_blocks([b44], True)
self.log.info("Reject a block with a non-coinbase as the first tx")
non_coinbase = self.create_tx(out[15], 0, 1)
b45 = CBlock()
b45.nTime = self.tip.nTime + 1
b45.hashPrevBlock = self.tip.sha256
b45.nBits = 0x207fffff
b45.vtx.append(non_coinbase)
b45.hashMerkleRoot = b45.calc_merkle_root()
b45.calc_sha256()
b45.solve()
self.block_heights[b45.sha256] = self.block_heights[self.tip.sha256] + 1
self.tip = b45
self.blocks[45] = b45
self.sync_blocks([b45], success=False, reject_reason='bad-cb-missing', reconnect=True)
self.log.info("Reject a block with no transactions")
self.move_tip(44)
b46 = CBlock()
b46.nTime = b44.nTime + 1
b46.hashPrevBlock = b44.sha256
b46.nBits = 0x207fffff
b46.vtx = []
b46.hashMerkleRoot = 0
b46.solve()
self.block_heights[b46.sha256] = self.block_heights[b44.sha256] + 1
self.tip = b46
assert 46 not in self.blocks
self.blocks[46] = b46
self.sync_blocks([b46], success=False, reject_reason='bad-blk-length', reconnect=True)
self.log.info("Reject a block with invalid work")
self.move_tip(44)
b47 = self.next_block(47, solve=False)
target = uint256_from_compact(b47.nBits)
while b47.sha256 < target:
b47.nNonce += 1
b47.rehash()
self.sync_blocks([b47], False, request_block=False)
self.log.info("Reject a block with a timestamp >2 hours in the future")
self.move_tip(44)
b48 = self.next_block(48, solve=False)
b48.nTime = int(time.time()) + 60 * 60 * 3
b48.solve()
self.sync_blocks([b48], False, request_block=False)
self.log.info("Reject a block with invalid merkle hash")
self.move_tip(44)
b49 = self.next_block(49)
b49.hashMerkleRoot += 1
b49.solve()
self.sync_blocks([b49], success=False, reject_reason='bad-txnmrklroot', reconnect=True)
self.log.info("Reject a block with incorrect POW limit")
self.move_tip(44)
b50 = self.next_block(50)
b50.nBits = b50.nBits - 1
b50.solve()
self.sync_blocks([b50], False, request_block=False, reconnect=True)
self.log.info("Reject a block with two coinbase transactions")
self.move_tip(44)
b51 = self.next_block(51)
cb2 = create_coinbase(51, self.coinbase_pubkey)
b51 = self.update_block(51, [cb2])
self.sync_blocks([b51], success=False, reject_reason='bad-cb-multiple', reconnect=True)
self.log.info("Reject a block with duplicate transactions")
# Note: txns have to be in the right position in the merkle tree to trigger this error
self.move_tip(44)
b52 = self.next_block(52, spend=out[15])
tx = self.create_tx(b52.vtx[1], 0, 1)
b52 = self.update_block(52, [tx, tx])
self.sync_blocks([b52], success=False, reject_reason='bad-txns-duplicate', reconnect=True)
# Test block timestamps
# -> b31 (8) -> b33 (9) -> b35 (10) -> b39 (11) -> b42 (12) -> b43 (13) -> b53 (14) -> b55 (15)
# \-> b54 (15)
#
self.move_tip(43)
b53 = self.next_block(53, spend=out[14])
self.sync_blocks([b53], False)
self.save_spendable_output()
self.log.info("Reject a block with timestamp before MedianTimePast")
b54 = self.next_block(54, spend=out[15])
b54.nTime = b35.nTime - 1
b54.solve()
self.sync_blocks([b54], False, request_block=False)
# valid timestamp
self.move_tip(53)
b55 = self.next_block(55, spend=out[15])
b55.nTime = b35.nTime
self.update_block(55, [])
self.sync_blocks([b55], True)
self.save_spendable_output()
# Test Merkle tree malleability
#
# -> b42 (12) -> b43 (13) -> b53 (14) -> b55 (15) -> b57p2 (16)
# \-> b57 (16)
# \-> b56p2 (16)
# \-> b56 (16)
#
# Merkle tree malleability (CVE-2012-2459): repeating sequences of transactions in a block without
# affecting the merkle root of a block, while still invalidating it.
# See: src/consensus/merkle.h
#
# b57 has three txns: coinbase, tx, tx1. The merkle root computation will duplicate tx.
# Result: OK
#
# b56 copies b57 but duplicates tx1 and does not recalculate the block hash. So it has a valid merkle
# root but duplicate transactions.
# Result: Fails
#
# b57p2 has six transactions in its merkle tree:
# - coinbase, tx, tx1, tx2, tx3, tx4
# Merkle root calculation will duplicate as necessary.
# Result: OK.
#
# b56p2 copies b57p2 but adds both tx3 and tx4. The purpose of the test is to make sure the code catches
# duplicate txns that are not next to one another with the "bad-txns-duplicate" error (which indicates
# that the error was caught early, avoiding a DOS vulnerability.)
# b57 - a good block with 2 txs, don't submit until end
self.move_tip(55)
b57 = self.next_block(57)
tx = self.create_and_sign_transaction(out[16], 1)
tx1 = self.create_tx(tx, 0, 1)
b57 = self.update_block(57, [tx, tx1])
# b56 - copy b57, add a duplicate tx
self.log.info("Reject a block with a duplicate transaction in the Merkle Tree (but with a valid Merkle Root)")
self.move_tip(55)
b56 = copy.deepcopy(b57)
self.blocks[56] = b56
assert_equal(len(b56.vtx), 3)
b56 = self.update_block(56, [tx1])
assert_equal(b56.hash, b57.hash)
self.sync_blocks([b56], success=False, reject_reason='bad-txns-duplicate', reconnect=True)
# b57p2 - a good block with 6 tx'es, don't submit until end
self.move_tip(55)
b57p2 = self.next_block("57p2")
tx = self.create_and_sign_transaction(out[16], 1)
tx1 = self.create_tx(tx, 0, 1)
tx2 = self.create_tx(tx1, 0, 1)
tx3 = self.create_tx(tx2, 0, 1)
tx4 = self.create_tx(tx3, 0, 1)
b57p2 = self.update_block("57p2", [tx, tx1, tx2, tx3, tx4])
# b56p2 - copy b57p2, duplicate two non-consecutive tx's
self.log.info("Reject a block with two duplicate transactions in the Merkle Tree (but with a valid Merkle Root)")
self.move_tip(55)
b56p2 = copy.deepcopy(b57p2)
self.blocks["b56p2"] = b56p2
assert_equal(b56p2.hash, b57p2.hash)
assert_equal(len(b56p2.vtx), 6)
b56p2 = self.update_block("b56p2", [tx3, tx4])
self.sync_blocks([b56p2], success=False, reject_reason='bad-txns-duplicate', reconnect=True)
self.move_tip("57p2")
self.sync_blocks([b57p2], True)
self.move_tip(57)
self.sync_blocks([b57], False) # The tip is not updated because 57p2 seen first
self.save_spendable_output()
# Test a few invalid tx types
#
# -> b35 (10) -> b39 (11) -> b42 (12) -> b43 (13) -> b53 (14) -> b55 (15) -> b57 (16) -> b60 (17)
# \-> ??? (17)
#
# tx with prevout.n out of range
self.log.info("Reject a block with a transaction with prevout.n out of range")
self.move_tip(57)
b58 = self.next_block(58, spend=out[17])
tx = CTransaction()
assert(len(out[17].vout) < 42)
tx.vin.append(CTxIn(COutPoint(out[17].sha256, 42), CScript([OP_TRUE]), 0xffffffff))
tx.vout.append(CTxOut(0, b""))
tx.calc_sha256()
b58 = self.update_block(58, [tx])
self.sync_blocks([b58], success=False, reject_reason='bad-txns-inputs-missingorspent', reconnect=True)
# tx with output value > input value
self.log.info("Reject a block with a transaction with outputs > inputs")
self.move_tip(57)
b59 = self.next_block(59)
tx = self.create_and_sign_transaction(out[17], 51 * COIN)
b59 = self.update_block(59, [tx])
self.sync_blocks([b59], success=False, reject_reason='bad-txns-in-belowout', reconnect=True)
# reset to good chain
self.move_tip(57)
b60 = self.next_block(60, spend=out[17])
self.sync_blocks([b60], True)
self.save_spendable_output()
# Test BIP30
#
# -> b39 (11) -> b42 (12) -> b43 (13) -> b53 (14) -> b55 (15) -> b57 (16) -> b60 (17)
# \-> b61 (18)
#
# Blocks are not allowed to contain a transaction whose id matches that of an earlier,
# not-fully-spent transaction in the same chain. To test, make identical coinbases;
# the second one should be rejected.
#
self.log.info("Reject a block with a transaction with a duplicate hash of a previous transaction (BIP30)")
self.move_tip(60)
b61 = self.next_block(61, spend=out[18])
b61.vtx[0].vin[0].scriptSig = b60.vtx[0].vin[0].scriptSig # Equalize the coinbases
b61.vtx[0].rehash()
b61 = self.update_block(61, [])
assert_equal(b60.vtx[0].serialize(), b61.vtx[0].serialize())
self.sync_blocks([b61], success=False, reject_reason='bad-txns-BIP30', reconnect=True)
# Test tx.isFinal is properly rejected (not an exhaustive tx.isFinal test, that should be in data-driven transaction tests)
#
# -> b39 (11) -> b42 (12) -> b43 (13) -> b53 (14) -> b55 (15) -> b57 (16) -> b60 (17)
# \-> b62 (18)
#
self.log.info("Reject a block with a transaction with a nonfinal locktime")
self.move_tip(60)
b62 = self.next_block(62)
tx = CTransaction()
tx.nLockTime = 0xffffffff # this locktime is non-final
tx.vin.append(CTxIn(COutPoint(out[18].sha256, 0))) # don't set nSequence
tx.vout.append(CTxOut(0, CScript([OP_TRUE])))
assert(tx.vin[0].nSequence < 0xffffffff)
tx.calc_sha256()
b62 = self.update_block(62, [tx])
self.sync_blocks([b62], success=False, reject_reason='bad-txns-nonfinal')
# Test a non-final coinbase is also rejected
#
# -> b39 (11) -> b42 (12) -> b43 (13) -> b53 (14) -> b55 (15) -> b57 (16) -> b60 (17)
# \-> b63 (-)
#
self.log.info("Reject a block with a coinbase transaction with a nonfinal locktime")
self.move_tip(60)
b63 = self.next_block(63)
b63.vtx[0].nLockTime = 0xffffffff
b63.vtx[0].vin[0].nSequence = 0xDEADBEEF
b63.vtx[0].rehash()
b63 = self.update_block(63, [])
self.sync_blocks([b63], success=False, reject_reason='bad-txns-nonfinal')
# This checks that a block with a bloated VARINT between the block_header and the array of tx such that
# the block is > MAX_BLOCK_BASE_SIZE with the bloated varint, but <= MAX_BLOCK_BASE_SIZE without the bloated varint,
# does not cause a subsequent, identical block with canonical encoding to be rejected. The test does not
# care whether the bloated block is accepted or rejected; it only cares that the second block is accepted.
#
# What matters is that the receiving node should not reject the bloated block, and then reject the canonical
# block on the basis that it's the same as an already-rejected block (which would be a consensus failure.)
#
# -> b39 (11) -> b42 (12) -> b43 (13) -> b53 (14) -> b55 (15) -> b57 (16) -> b60 (17) -> b64 (18)
# \
# b64a (18)
# b64a is a bloated block (non-canonical varint)
# b64 is a good block (same as b64 but w/ canonical varint)
#
self.log.info("Accept a valid block even if a bloated version of the block has previously been sent")
self.move_tip(60)
regular_block = self.next_block("64a", spend=out[18])
# make it a "broken_block," with non-canonical serialization
b64a = CBrokenBlock(regular_block)
b64a.initialize(regular_block)
self.blocks["64a"] = b64a
self.tip = b64a
tx = CTransaction()
# use canonical serialization to calculate size
script_length = MAX_BLOCK_BASE_SIZE - len(b64a.normal_serialize()) - 69
script_output = CScript([b'\x00' * script_length])
tx.vout.append(CTxOut(0, script_output))
tx.vin.append(CTxIn(COutPoint(b64a.vtx[1].sha256, 0)))
b64a = self.update_block("64a", [tx])
assert_equal(len(b64a.serialize()), MAX_BLOCK_BASE_SIZE + 8)
self.sync_blocks([b64a], success=False, reject_reason='non-canonical ReadCompactSize():')
# bitcoind doesn't disconnect us for sending a bloated block, but if we subsequently
# resend the header message, it won't send us the getdata message again. Just
# disconnect and reconnect and then call sync_blocks.
# TODO: improve this test to be less dependent on P2P DOS behaviour.
node.disconnect_p2ps()
self.reconnect_p2p()
self.move_tip(60)
b64 = CBlock(b64a)
b64.vtx = copy.deepcopy(b64a.vtx)
assert_equal(b64.hash, b64a.hash)
assert_equal(len(b64.serialize()), MAX_BLOCK_BASE_SIZE)
self.blocks[64] = b64
b64 = self.update_block(64, [])
self.sync_blocks([b64], True)
self.save_spendable_output()
# Spend an output created in the block itself
#
# -> b42 (12) -> b43 (13) -> b53 (14) -> b55 (15) -> b57 (16) -> b60 (17) -> b64 (18) -> b65 (19)
#
self.log.info("Accept a block with a transaction spending an output created in the same block")
self.move_tip(64)
b65 = self.next_block(65)
tx1 = self.create_and_sign_transaction(out[19], out[19].vout[0].nValue)
tx2 = self.create_and_sign_transaction(tx1, 0)
b65 = self.update_block(65, [tx1, tx2])
self.sync_blocks([b65], True)
self.save_spendable_output()
# Attempt to spend an output created later in the same block
#
# -> b43 (13) -> b53 (14) -> b55 (15) -> b57 (16) -> b60 (17) -> b64 (18) -> b65 (19)
# \-> b66 (20)
self.log.info("Reject a block with a transaction spending an output created later in the same block")
self.move_tip(65)
b66 = self.next_block(66)
tx1 = self.create_and_sign_transaction(out[20], out[20].vout[0].nValue)
tx2 = self.create_and_sign_transaction(tx1, 1)
b66 = self.update_block(66, [tx2, tx1])
self.sync_blocks([b66], success=False, reject_reason='bad-txns-inputs-missingorspent', reconnect=True)
# Attempt to double-spend a transaction created in a block
#
# -> b43 (13) -> b53 (14) -> b55 (15) -> b57 (16) -> b60 (17) -> b64 (18) -> b65 (19)
# \-> b67 (20)
#
#
self.log.info("Reject a block with a transaction double spending a transaction creted in the same block")
self.move_tip(65)
b67 = self.next_block(67)
tx1 = self.create_and_sign_transaction(out[20], out[20].vout[0].nValue)
tx2 = self.create_and_sign_transaction(tx1, 1)
tx3 = self.create_and_sign_transaction(tx1, 2)
b67 = self.update_block(67, [tx1, tx2, tx3])
self.sync_blocks([b67], success=False, reject_reason='bad-txns-inputs-missingorspent', reconnect=True)
# More tests of block subsidy
#
# -> b43 (13) -> b53 (14) -> b55 (15) -> b57 (16) -> b60 (17) -> b64 (18) -> b65 (19) -> b69 (20)
# \-> b68 (20)
#
# b68 - coinbase with an extra 10 satoshis,
# creates a tx that has 9 satoshis from out[20] go to fees
# this fails because the coinbase is trying to claim 1 satoshi too much in fees
#
# b69 - coinbase with extra 10 satoshis, and a tx that gives a 10 satoshi fee
# this succeeds
#
self.log.info("Reject a block trying to claim too much subsidy in the coinbase transaction")
self.move_tip(65)
b68 = self.next_block(68, additional_coinbase_value=10)
tx = self.create_and_sign_transaction(out[20], out[20].vout[0].nValue - 9)
b68 = self.update_block(68, [tx])
self.sync_blocks([b68], success=False, reject_reason='bad-cb-amount', reconnect=True)
self.log.info("Accept a block claiming the correct subsidy in the coinbase transaction")
self.move_tip(65)
b69 = self.next_block(69, additional_coinbase_value=10)
tx = self.create_and_sign_transaction(out[20], out[20].vout[0].nValue - 10)
self.update_block(69, [tx])
self.sync_blocks([b69], True)
self.save_spendable_output()
# Test spending the outpoint of a non-existent transaction
#
# -> b53 (14) -> b55 (15) -> b57 (16) -> b60 (17) -> b64 (18) -> b65 (19) -> b69 (20)
# \-> b70 (21)
#
self.log.info("Reject a block containing a transaction spending from a non-existent input")
self.move_tip(69)
b70 = self.next_block(70, spend=out[21])
bogus_tx = CTransaction()
bogus_tx.sha256 = uint256_from_str(b"23c70ed7c0506e9178fc1a987f40a33946d4ad4c962b5ae3a52546da53af0c5c")
tx = CTransaction()
tx.vin.append(CTxIn(COutPoint(bogus_tx.sha256, 0), b"", 0xffffffff))
tx.vout.append(CTxOut(1, b""))
b70 = self.update_block(70, [tx])
self.sync_blocks([b70], success=False, reject_reason='bad-txns-inputs-missingorspent', reconnect=True)
# Test accepting an invalid block which has the same hash as a valid one (via merkle tree tricks)
#
# -> b53 (14) -> b55 (15) -> b57 (16) -> b60 (17) -> b64 (18) -> b65 (19) -> b69 (20) -> b72 (21)
# \-> b71 (21)
#
# b72 is a good block.
# b71 is a copy of 72, but re-adds one of its transactions. However, it has the same hash as b72.
self.log.info("Reject a block containing a duplicate transaction but with the same Merkle root (Merkle tree malleability")
self.move_tip(69)
b72 = self.next_block(72)
tx1 = self.create_and_sign_transaction(out[21], 2)
tx2 = self.create_and_sign_transaction(tx1, 1)
b72 = self.update_block(72, [tx1, tx2]) # now tip is 72
b71 = copy.deepcopy(b72)
b71.vtx.append(tx2) # add duplicate tx2
self.block_heights[b71.sha256] = self.block_heights[b69.sha256] + 1 # b71 builds off b69
self.blocks[71] = b71
assert_equal(len(b71.vtx), 4)
assert_equal(len(b72.vtx), 3)
assert_equal(b72.sha256, b71.sha256)
self.move_tip(71)
self.sync_blocks([b71], success=False, reject_reason='bad-txns-duplicate', reconnect=True)
self.move_tip(72)
self.sync_blocks([b72], True)
self.save_spendable_output()
# Test some invalid scripts and MAX_BLOCK_SIGOPS
#
# -> b55 (15) -> b57 (16) -> b60 (17) -> b64 (18) -> b65 (19) -> b69 (20) -> b72 (21)
# \-> b** (22)
#
# b73 - tx with excessive sigops that are placed after an excessively large script element.
# The purpose of the test is to make sure those sigops are counted.
#
# script is a bytearray of size 20,526
#
# bytearray[0-19,998] : OP_CHECKSIG
# bytearray[19,999] : OP_PUSHDATA4
# bytearray[20,000-20,003]: 521 (max_script_element_size+1, in little-endian format)
# bytearray[20,004-20,525]: unread data (script_element)
# bytearray[20,526] : OP_CHECKSIG (this puts us over the limit)
self.log.info("Reject a block containing too many sigops after a large script element")
self.move_tip(72)
b73 = self.next_block(73)
size = MAX_BLOCK_SIGOPS - 1 + MAX_SCRIPT_ELEMENT_SIZE + 1 + 5 + 1
a = bytearray([OP_CHECKSIG] * size)
a[MAX_BLOCK_SIGOPS - 1] = int("4e", 16) # OP_PUSHDATA4
element_size = MAX_SCRIPT_ELEMENT_SIZE + 1
a[MAX_BLOCK_SIGOPS] = element_size % 256
a[MAX_BLOCK_SIGOPS + 1] = element_size // 256
a[MAX_BLOCK_SIGOPS + 2] = 0
a[MAX_BLOCK_SIGOPS + 3] = 0
tx = self.create_and_sign_transaction(out[22], 1, CScript(a))
b73 = self.update_block(73, [tx])
assert_equal(get_legacy_sigopcount_block(b73), MAX_BLOCK_SIGOPS + 1)
self.sync_blocks([b73], success=False, reject_reason='bad-blk-sigops', reconnect=True)
# b74/75 - if we push an invalid script element, all previous sigops are counted,
# but sigops after the element are not counted.
#
# The invalid script element is that the push_data indicates that
# there will be a large amount of data (0xffffff bytes), but we only
# provide a much smaller number. These bytes are CHECKSIGS so they would
# cause b75 to fail for excessive sigops, if those bytes were counted.
#
# b74 fails because we put MAX_BLOCK_SIGOPS+1 before the element