Merge #11742: rpc: Add testmempoolaccept

b55555d rpc: Add testmempoolaccept (MarcoFalke)

Pull request description:

  To check if a single raw transaction makes it into the current transaction pool, one had to call `sendrawtransaction`. However, on success, this adds the transaction to the mempool with no easy way to undo.

  The call `testmempoolaccept` is introduced to provide a way to solely check the result without changing the mempool state.

Tree-SHA512: 5afd9311190135cee8fc1f229c7d39bf893f1028f29e28d34f70df820198ff97b4bf86b41cbbd6e6c36a5c30073cefa92d541c74a4939c7a2a6fa283dfd41b63

4 files changed, 300 insertions, 5 deletions

diff --git a/test/functional/mempool_accept.py b/test/functional/mempool_accept.py
new file mode 100755
index 0000000000..7cdb24c6a5
--- /dev/null
+++ b/test/functional/mempool_accept.py
@@ -0,0 +1,293 @@
+#!/usr/bin/env python3
+# Copyright (c) 2017 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 mempool acceptance of raw transactions."""
+
+from io import BytesIO
+from test_framework.test_framework import BitcoinTestFramework
+from test_framework.messages import (
+    BIP125_SEQUENCE_NUMBER,
+    COIN,
+    COutPoint,
+    CTransaction,
+    CTxOut,
+    MAX_BLOCK_BASE_SIZE,
+)
+from test_framework.script import (
+    hash160,
+    CScript,
+    OP_0,
+    OP_EQUAL,
+    OP_HASH160,
+    OP_RETURN,
+)
+from test_framework.util import (
+    assert_equal,
+    assert_raises_rpc_error,
+    bytes_to_hex_str,
+    hex_str_to_bytes,
+    wait_until,
+)
+
+
+class MempoolAcceptanceTest(BitcoinTestFramework):
+    def set_test_params(self):
+        self.num_nodes = 1
+        self.extra_args = [[
+            '-checkmempool',
+            '-txindex',
+            '-reindex',  # Need reindex for txindex
+            '-acceptnonstdtxn=0',  # Try to mimic main-net
+        ]] * self.num_nodes
+
+    def check_mempool_result(self, result_expected, *args, **kwargs):
+        """Wrapper to check result of testmempoolaccept on node_0's mempool"""
+        result_test = self.nodes[0].testmempoolaccept(*args, **kwargs)
+        assert_equal(result_expected, result_test)
+        assert_equal(self.nodes[0].getmempoolinfo()['size'], self.mempool_size)  # Must not change mempool state
+
+    def run_test(self):
+        node = self.nodes[0]
+
+        self.log.info('Start with empty mempool, and 200 blocks')
+        self.mempool_size = 0
+        wait_until(lambda: node.getblockcount() == 200)
+        assert_equal(node.getmempoolinfo()['size'], self.mempool_size)
+
+        self.log.info('Should not accept garbage to testmempoolaccept')
+        assert_raises_rpc_error(-3, 'Expected type array, got string', lambda: node.testmempoolaccept(rawtxs='ff00baar'))
+        assert_raises_rpc_error(-8, 'Array must contain exactly one raw transaction for now', lambda: node.testmempoolaccept(rawtxs=['ff00baar', 'ff22']))
+        assert_raises_rpc_error(-22, 'TX decode failed', lambda: node.testmempoolaccept(rawtxs=['ff00baar']))
+
+        self.log.info('A transaction already in the blockchain')
+        coin = node.listunspent()[0]  # Pick a random coin(base) to spend
+        raw_tx_in_block = node.signrawtransactionwithwallet(node.createrawtransaction(
+            inputs=[{'txid': coin['txid'], 'vout': coin['vout']}],
+            outputs=[{node.getnewaddress(): 0.3}, {node.getnewaddress(): 49}],
+        ))['hex']
+        txid_in_block = node.sendrawtransaction(hexstring=raw_tx_in_block, allowhighfees=True)
+        node.generate(1)
+        self.check_mempool_result(
+            result_expected=[{'txid': txid_in_block, 'allowed': False, 'reject-reason': '18: txn-already-known'}],
+            rawtxs=[raw_tx_in_block],
+        )
+
+        self.log.info('A transaction not in the mempool')
+        fee = 0.00000700
+        raw_tx_0 = node.signrawtransactionwithwallet(node.createrawtransaction(
+            inputs=[{"txid": txid_in_block, "vout": 0, "sequence": BIP125_SEQUENCE_NUMBER}],  # RBF is used later
+            outputs=[{node.getnewaddress(): 0.3 - fee}],
+        ))['hex']
+        tx = CTransaction()
+        tx.deserialize(BytesIO(hex_str_to_bytes(raw_tx_0)))
+        txid_0 = tx.rehash()
+        self.check_mempool_result(
+            result_expected=[{'txid': txid_0, 'allowed': True}],
+            rawtxs=[raw_tx_0],
+        )
+
+        self.log.info('A transaction in the mempool')
+        node.sendrawtransaction(hexstring=raw_tx_0)
+        self.mempool_size = 1
+        self.check_mempool_result(
+            result_expected=[{'txid': txid_0, 'allowed': False, 'reject-reason': '18: txn-already-in-mempool'}],
+            rawtxs=[raw_tx_0],
+        )
+
+        self.log.info('A transaction that replaces a mempool transaction')
+        tx.deserialize(BytesIO(hex_str_to_bytes(raw_tx_0)))
+        tx.vout[0].nValue -= int(fee * COIN)  # Double the fee
+        tx.vin[0].nSequence = BIP125_SEQUENCE_NUMBER + 1  # Now, opt out of RBF
+        raw_tx_0 = node.signrawtransactionwithwallet(bytes_to_hex_str(tx.serialize()))['hex']
+        tx.deserialize(BytesIO(hex_str_to_bytes(raw_tx_0)))
+        txid_0 = tx.rehash()
+        self.check_mempool_result(
+            result_expected=[{'txid': txid_0, 'allowed': True}],
+            rawtxs=[raw_tx_0],
+        )
+
+        self.log.info('A transaction that conflicts with an unconfirmed tx')
+        # Send the transaction that replaces the mempool transaction and opts out of replaceability
+        node.sendrawtransaction(hexstring=bytes_to_hex_str(tx.serialize()), allowhighfees=True)
+        # take original raw_tx_0
+        tx.deserialize(BytesIO(hex_str_to_bytes(raw_tx_0)))
+        tx.vout[0].nValue -= int(4 * fee * COIN)  # Set more fee
+        # skip re-signing the tx
+        self.check_mempool_result(
+            result_expected=[{'txid': tx.rehash(), 'allowed': False, 'reject-reason': '18: txn-mempool-conflict'}],
+            rawtxs=[bytes_to_hex_str(tx.serialize())],
+            allowhighfees=True,
+        )
+
+        self.log.info('A transaction with missing inputs, that never existed')
+        tx.deserialize(BytesIO(hex_str_to_bytes(raw_tx_0)))
+        tx.vin[0].prevout = COutPoint(hash=int('ff' * 32, 16), n=14)
+        # skip re-signing the tx
+        self.check_mempool_result(
+            result_expected=[{'txid': tx.rehash(), 'allowed': False, 'reject-reason': 'missing-inputs'}],
+            rawtxs=[bytes_to_hex_str(tx.serialize())],
+        )
+
+        self.log.info('A transaction with missing inputs, that existed once in the past')
+        tx.deserialize(BytesIO(hex_str_to_bytes(raw_tx_0)))
+        tx.vin[0].prevout.n = 1  # Set vout to 1, to spend the other outpoint (49 coins) of the in-chain-tx we want to double spend
+        raw_tx_1 = node.signrawtransactionwithwallet(bytes_to_hex_str(tx.serialize()))['hex']
+        txid_1 = node.sendrawtransaction(hexstring=raw_tx_1, allowhighfees=True)
+        # Now spend both to "clearly hide" the outputs, ie. remove the coins from the utxo set by spending them
+        raw_tx_spend_both = node.signrawtransactionwithwallet(node.createrawtransaction(
+            inputs=[
+                {'txid': txid_0, 'vout': 0},
+                {'txid': txid_1, 'vout': 0},
+            ],
+            outputs=[{node.getnewaddress(): 0.1}]
+        ))['hex']
+        txid_spend_both = node.sendrawtransaction(hexstring=raw_tx_spend_both, allowhighfees=True)
+        node.generate(1)
+        self.mempool_size = 0
+        # Now see if we can add the coins back to the utxo set by sending the exact txs again
+        self.check_mempool_result(
+            result_expected=[{'txid': txid_0, 'allowed': False, 'reject-reason': 'missing-inputs'}],
+            rawtxs=[raw_tx_0],
+        )
+        self.check_mempool_result(
+            result_expected=[{'txid': txid_1, 'allowed': False, 'reject-reason': 'missing-inputs'}],
+            rawtxs=[raw_tx_1],
+        )
+
+        self.log.info('Create a signed "reference" tx for later use')
+        raw_tx_reference = node.signrawtransactionwithwallet(node.createrawtransaction(
+            inputs=[{'txid': txid_spend_both, 'vout': 0}],
+            outputs=[{node.getnewaddress(): 0.05}],
+        ))['hex']
+        tx.deserialize(BytesIO(hex_str_to_bytes(raw_tx_reference)))
+        # Reference tx should be valid on itself
+        self.check_mempool_result(
+            result_expected=[{'txid': tx.rehash(), 'allowed': True}],
+            rawtxs=[bytes_to_hex_str(tx.serialize())],
+        )
+
+        self.log.info('A transaction with no outputs')
+        tx.deserialize(BytesIO(hex_str_to_bytes(raw_tx_reference)))
+        tx.vout = []
+        # Skip re-signing the transaction for context independent checks from now on
+        # tx.deserialize(BytesIO(hex_str_to_bytes(node.signrawtransactionwithwallet(bytes_to_hex_str(tx.serialize()))['hex'])))
+        self.check_mempool_result(
+            result_expected=[{'txid': tx.rehash(), 'allowed': False, 'reject-reason': '16: bad-txns-vout-empty'}],
+            rawtxs=[bytes_to_hex_str(tx.serialize())],
+        )
+
+        self.log.info('A really large transaction')
+        tx.deserialize(BytesIO(hex_str_to_bytes(raw_tx_reference)))
+        tx.vin = [tx.vin[0]] * (MAX_BLOCK_BASE_SIZE // len(tx.vin[0].serialize()))
+        self.check_mempool_result(
+            result_expected=[{'txid': tx.rehash(), 'allowed': False, 'reject-reason': '16: bad-txns-oversize'}],
+            rawtxs=[bytes_to_hex_str(tx.serialize())],
+        )
+
+        self.log.info('A transaction with negative output value')
+        tx.deserialize(BytesIO(hex_str_to_bytes(raw_tx_reference)))
+        tx.vout[0].nValue *= -1
+        self.check_mempool_result(
+            result_expected=[{'txid': tx.rehash(), 'allowed': False, 'reject-reason': '16: bad-txns-vout-negative'}],
+            rawtxs=[bytes_to_hex_str(tx.serialize())],
+        )
+
+        self.log.info('A transaction with too large output value')
+        tx.deserialize(BytesIO(hex_str_to_bytes(raw_tx_reference)))
+        tx.vout[0].nValue = 21000000 * COIN + 1
+        self.check_mempool_result(
+            result_expected=[{'txid': tx.rehash(), 'allowed': False, 'reject-reason': '16: bad-txns-vout-toolarge'}],
+            rawtxs=[bytes_to_hex_str(tx.serialize())],
+        )
+
+        self.log.info('A transaction with too large sum of output values')
+        tx.deserialize(BytesIO(hex_str_to_bytes(raw_tx_reference)))
+        tx.vout = [tx.vout[0]] * 2
+        tx.vout[0].nValue = 21000000 * COIN
+        self.check_mempool_result(
+            result_expected=[{'txid': tx.rehash(), 'allowed': False, 'reject-reason': '16: bad-txns-txouttotal-toolarge'}],
+            rawtxs=[bytes_to_hex_str(tx.serialize())],
+        )
+
+        self.log.info('A transaction with duplicate inputs')
+        tx.deserialize(BytesIO(hex_str_to_bytes(raw_tx_reference)))
+        tx.vin = [tx.vin[0]] * 2
+        self.check_mempool_result(
+            result_expected=[{'txid': tx.rehash(), 'allowed': False, 'reject-reason': '16: bad-txns-inputs-duplicate'}],
+            rawtxs=[bytes_to_hex_str(tx.serialize())],
+        )
+
+        self.log.info('A coinbase transaction')
+        # Pick the input of the first tx we signed, so it has to be a coinbase tx
+        raw_tx_coinbase_spent = node.getrawtransaction(txid=node.decoderawtransaction(hexstring=raw_tx_in_block)['vin'][0]['txid'])
+        tx.deserialize(BytesIO(hex_str_to_bytes(raw_tx_coinbase_spent)))
+        self.check_mempool_result(
+            result_expected=[{'txid': tx.rehash(), 'allowed': False, 'reject-reason': '16: coinbase'}],
+            rawtxs=[bytes_to_hex_str(tx.serialize())],
+        )
+
+        self.log.info('Some nonstandard transactions')
+        tx.deserialize(BytesIO(hex_str_to_bytes(raw_tx_reference)))
+        tx.nVersion = 3  # A version currently non-standard
+        self.check_mempool_result(
+            result_expected=[{'txid': tx.rehash(), 'allowed': False, 'reject-reason': '64: version'}],
+            rawtxs=[bytes_to_hex_str(tx.serialize())],
+        )
+        tx.deserialize(BytesIO(hex_str_to_bytes(raw_tx_reference)))
+        tx.vout[0].scriptPubKey = CScript([OP_0])  # Some non-standard script
+        self.check_mempool_result(
+            result_expected=[{'txid': tx.rehash(), 'allowed': False, 'reject-reason': '64: scriptpubkey'}],
+            rawtxs=[bytes_to_hex_str(tx.serialize())],
+        )
+        tx.deserialize(BytesIO(hex_str_to_bytes(raw_tx_reference)))
+        tx.vin[0].scriptSig = CScript([OP_HASH160])  # Some not-pushonly scriptSig
+        self.check_mempool_result(
+            result_expected=[{'txid': tx.rehash(), 'allowed': False, 'reject-reason': '64: scriptsig-not-pushonly'}],
+            rawtxs=[bytes_to_hex_str(tx.serialize())],
+        )
+        tx.deserialize(BytesIO(hex_str_to_bytes(raw_tx_reference)))
+        output_p2sh_burn = CTxOut(nValue=540, scriptPubKey=CScript([OP_HASH160, hash160(b'burn'), OP_EQUAL]))
+        num_scripts = 100000 // len(output_p2sh_burn.serialize())  # Use enough outputs to make the tx too large for our policy
+        tx.vout = [output_p2sh_burn] * num_scripts
+        self.check_mempool_result(
+            result_expected=[{'txid': tx.rehash(), 'allowed': False, 'reject-reason': '64: tx-size'}],
+            rawtxs=[bytes_to_hex_str(tx.serialize())],
+        )
+        tx.deserialize(BytesIO(hex_str_to_bytes(raw_tx_reference)))
+        tx.vout[0] = output_p2sh_burn
+        tx.vout[0].nValue -= 1  # Make output smaller, such that it is dust for our policy
+        self.check_mempool_result(
+            result_expected=[{'txid': tx.rehash(), 'allowed': False, 'reject-reason': '64: dust'}],
+            rawtxs=[bytes_to_hex_str(tx.serialize())],
+        )
+        tx.deserialize(BytesIO(hex_str_to_bytes(raw_tx_reference)))
+        tx.vout[0].scriptPubKey = CScript([OP_RETURN, b'\xff'])
+        tx.vout = [tx.vout[0]] * 2
+        self.check_mempool_result(
+            result_expected=[{'txid': tx.rehash(), 'allowed': False, 'reject-reason': '64: multi-op-return'}],
+            rawtxs=[bytes_to_hex_str(tx.serialize())],
+        )
+
+        self.log.info('A timelocked transaction')
+        tx.deserialize(BytesIO(hex_str_to_bytes(raw_tx_reference)))
+        tx.vin[0].nSequence -= 1  # Should be non-max, so locktime is not ignored
+        tx.nLockTime = node.getblockcount() + 1
+        self.check_mempool_result(
+            result_expected=[{'txid': tx.rehash(), 'allowed': False, 'reject-reason': '64: non-final'}],
+            rawtxs=[bytes_to_hex_str(tx.serialize())],
+        )
+
+        self.log.info('A transaction that is locked by BIP68 sequence logic')
+        tx.deserialize(BytesIO(hex_str_to_bytes(raw_tx_reference)))
+        tx.vin[0].nSequence = 2  # We could include it in the second block mined from now, but not the very next one
+        # Can skip re-signing the tx because of early rejection
+        self.check_mempool_result(
+            result_expected=[{'txid': tx.rehash(), 'allowed': False, 'reject-reason': '64: non-BIP68-final'}],
+            rawtxs=[bytes_to_hex_str(tx.serialize())],
+            allowhighfees=True,
+        )
+
+
+if __name__ == '__main__':
+    MempoolAcceptanceTest().main()
diff --git a/test/functional/test_framework/messages.py b/test/functional/test_framework/messages.py
index ee573e01cc..ca2e425bd6 100755
--- a/test/functional/test_framework/messages.py
+++ b/test/functional/test_framework/messages.py
@@ -34,7 +34,9 @@ MY_RELAY = 1 # from version 70001 onwards, fRelay should be appended to version
 MAX_INV_SZ = 50000
 MAX_BLOCK_BASE_SIZE = 1000000
 
-COIN = 100000000 # 1 btc in satoshis
+COIN = 100000000  # 1 btc in satoshis
+
+BIP125_SEQUENCE_NUMBER = 0xfffffffd  # Sequence number that is BIP 125 opt-in and BIP 68-opt-out
 
 NODE_NETWORK = (1 << 0)
 # NODE_GETUTXO = (1 << 1)
@@ -470,6 +472,7 @@ class CTransaction():
     def rehash(self):
         self.sha256 = None
         self.calc_sha256()
+        return self.hash
 
     # We will only cache the serialization without witness in
     # self.sha256 and self.hash -- those are expected to be the txid.
diff --git a/test/functional/test_runner.py b/test/functional/test_runner.py
index a2e92dce3b..3cae4b1df3 100755
--- a/test/functional/test_runner.py
+++ b/test/functional/test_runner.py
@@ -55,7 +55,7 @@ TEST_EXIT_SKIPPED = 77
 # 20 minutes represented in seconds
 TRAVIS_TIMEOUT_DURATION = 20 * 60
 
-BASE_SCRIPTS= [
+BASE_SCRIPTS = [
     # Scripts that are run by the travis build process.
     # Longest test should go first, to favor running tests in parallel
     'wallet_hd.py',
@@ -118,6 +118,7 @@ BASE_SCRIPTS= [
     'wallet_importprunedfunds.py',
     'rpc_signmessage.py',
     'feature_nulldummy.py',
+    'mempool_accept.py',
     'wallet_import_rescan.py',
     'mining_basic.py',
     'wallet_bumpfee.py',
diff --git a/test/functional/wallet_bumpfee.py b/test/functional/wallet_bumpfee.py
index 3e496248fd..5efc846b6e 100755
--- a/test/functional/wallet_bumpfee.py
+++ b/test/functional/wallet_bumpfee.py
@@ -17,14 +17,12 @@ make assumptions about execution order.
 from test_framework.blocktools import send_to_witness
 from test_framework.test_framework import BitcoinTestFramework
 from test_framework import blocktools
+from test_framework.messages import BIP125_SEQUENCE_NUMBER
 from test_framework.mininode import CTransaction
 from test_framework.util import *
 
 import io
 
-# Sequence number that is BIP 125 opt-in and BIP 68-compliant
-BIP125_SEQUENCE_NUMBER = 0xfffffffd
-
 WALLET_PASSPHRASE = "test"
 WALLET_PASSPHRASE_TIMEOUT = 3600