Merge #14811: Mining: Enforce that segwit option must be set in GBT

d2ce315fbf [docs] add release note for change to GBT (John Newbery)
0025c9eae4 [mining] segwit option must be set in GBT (John Newbery)

Pull request description:

  Calling getblocktemplate without the segwit rule specified is most
  likely a client error, since it results in lower fees for the miner.
  Prevent this client error by failing getblocktemplate if called without
  the segwit rule specified.

  Of the previous 1000 blocks (measured at block [551591 (hash 0x...173c811)](https://blockstream.info/block/000000000000000000173c811e79858808abc3216af607035973f002bef60a7a)), 991 included segwit transactions.

Tree-SHA512: 7933b073d72683c9ab9318db46a085ec19a56a14937945c73f783ac7656887619a86b74db0bdfcb8121df44f63a1d6a6fb19e98505b2a26a6a8a6e768e442fee

test/functional/feature_segwit.py

@@ -90,7 +90,7 @@ class SegWitTest(BitcoinTestFramework):
 
         self.log.info("Verify sigops are counted in GBT with pre-BIP141 rules before the fork")
         txid = self.nodes[0].sendtoaddress(self.nodes[0].getnewaddress(), 1)
-        tmpl = self.nodes[0].getblocktemplate({})
+        tmpl = self.nodes[0].getblocktemplate({'rules': ['segwit']})
         assert(tmpl['sizelimit'] == 1000000)
         assert('weightlimit' not in tmpl)
         assert(tmpl['sigoplimit'] == 20000)
@@ -232,15 +232,7 @@ class SegWitTest(BitcoinTestFramework):
         assert(tx.wit.is_null())
         assert(txid3 in self.nodes[0].getrawmempool())
 
-        # Now try calling getblocktemplate() without segwit support.
-        template = self.nodes[0].getblocktemplate()
-
-        # Check that tx1 is the only transaction of the 3 in the template.
-        template_txids = [t['txid'] for t in template['transactions']]
-        assert(txid2 not in template_txids and txid3 not in template_txids)
-        assert(txid1 in template_txids)
-
-        # Check that running with segwit support results in all 3 being included.
+        # Check that getblocktemplate includes all transactions.
         template = self.nodes[0].getblocktemplate({"rules": ["segwit"]})
         template_txids = [t['txid'] for t in template['transactions']]
         assert(txid1 in template_txids)

test/functional/mining_basic.py

@@ -30,7 +30,7 @@ from test_framework.script import CScriptNum
 def assert_template(node, block, expect, rehash=True):
     if rehash:
         block.hashMerkleRoot = block.calc_merkle_root()
-    rsp = node.getblocktemplate(template_request={'data': b2x(block.serialize()), 'mode': 'proposal'})
+    rsp = node.getblocktemplate(template_request={'data': b2x(block.serialize()), 'mode': 'proposal', 'rules': ['segwit']})
     assert_equal(rsp, expect)
 
 
@@ -60,7 +60,7 @@ class MiningTest(BitcoinTestFramework):
 
         # Mine a block to leave initial block download
         node.generatetoaddress(1, node.get_deterministic_priv_key().address)
-        tmpl = node.getblocktemplate()
+        tmpl = node.getblocktemplate({'rules': ['segwit']})
         self.log.info("getblocktemplate: Test capability advertised")
         assert 'proposal' in tmpl['capabilities']
         assert 'coinbasetxn' not in tmpl
@@ -86,6 +86,9 @@ class MiningTest(BitcoinTestFramework):
         block.nNonce = 0
         block.vtx = [coinbase_tx]
 
+        self.log.info("getblocktemplate: segwit rule must be set")
+        assert_raises_rpc_error(-8, "getblocktemplate must be called with the segwit rule set", node.getblocktemplate)
+
         self.log.info("getblocktemplate: Test valid block")
         assert_template(node, block, None)
 
@@ -102,7 +105,7 @@ class MiningTest(BitcoinTestFramework):
         assert_raises_rpc_error(-22, "Block does not start with a coinbase", node.submitblock, b2x(bad_block.serialize()))
 
         self.log.info("getblocktemplate: Test truncated final transaction")
-        assert_raises_rpc_error(-22, "Block decode failed", node.getblocktemplate, {'data': b2x(block.serialize()[:-1]), 'mode': 'proposal'})
+        assert_raises_rpc_error(-22, "Block decode failed", node.getblocktemplate, {'data': b2x(block.serialize()[:-1]), 'mode': 'proposal', 'rules': ['segwit']})
 
         self.log.info("getblocktemplate: Test duplicate transaction")
         bad_block = copy.deepcopy(block)
@@ -132,7 +135,7 @@ class MiningTest(BitcoinTestFramework):
         bad_block_sn = bytearray(block.serialize())
         assert_equal(bad_block_sn[TX_COUNT_OFFSET], 1)
         bad_block_sn[TX_COUNT_OFFSET] += 1
-        assert_raises_rpc_error(-22, "Block decode failed", node.getblocktemplate, {'data': b2x(bad_block_sn), 'mode': 'proposal'})
+        assert_raises_rpc_error(-22, "Block decode failed", node.getblocktemplate, {'data': b2x(bad_block_sn), 'mode': 'proposal', 'rules': ['segwit']})
 
         self.log.info("getblocktemplate: Test bad bits")
         bad_block = copy.deepcopy(block)

test/functional/mining_getblocktemplate_longpoll.py

@@ -15,14 +15,14 @@ class LongpollThread(threading.Thread):
     def __init__(self, node):
         threading.Thread.__init__(self)
         # query current longpollid
-        template = node.getblocktemplate()
+        template = node.getblocktemplate({'rules': ['segwit']})
         self.longpollid = template['longpollid']
         # create a new connection to the node, we can't use the same
         # connection from two threads
         self.node = get_rpc_proxy(node.url, 1, timeout=600, coveragedir=node.coverage_dir)
 
     def run(self):
-        self.node.getblocktemplate({'longpollid':self.longpollid})
+        self.node.getblocktemplate({'longpollid': self.longpollid, 'rules': ['segwit']})
 
 class GetBlockTemplateLPTest(BitcoinTestFramework):
     def set_test_params(self):
@@ -34,10 +34,10 @@ class GetBlockTemplateLPTest(BitcoinTestFramework):
     def run_test(self):
         self.log.info("Warning: this test will take about 70 seconds in the best case. Be patient.")
         self.nodes[0].generate(10)
-        template = self.nodes[0].getblocktemplate()
+        template = self.nodes[0].getblocktemplate({'rules': ['segwit']})
         longpollid = template['longpollid']
         # longpollid should not change between successive invocations if nothing else happens
-        template2 = self.nodes[0].getblocktemplate()
+        template2 = self.nodes[0].getblocktemplate({'rules': ['segwit']})
         assert(template2['longpollid'] == longpollid)
 
         # Test 1: test that the longpolling wait if we do nothing

test/functional/mining_prioritisetransaction.py

@@ -142,10 +142,10 @@ class PrioritiseTransactionTest(BitcoinTestFramework):
         # getblocktemplate to (eventually) return a new block.
         mock_time = int(time.time())
         self.nodes[0].setmocktime(mock_time)
-        template = self.nodes[0].getblocktemplate()
+        template = self.nodes[0].getblocktemplate({'rules': ['segwit']})
         self.nodes[0].prioritisetransaction(txid=tx_id, fee_delta=-int(self.relayfee*COIN))
         self.nodes[0].setmocktime(mock_time+10)
-        new_template = self.nodes[0].getblocktemplate()
+        new_template = self.nodes[0].getblocktemplate({'rules': ['segwit']})
 
         assert(template != new_template)
 

test/functional/p2p_segwit.py

@@ -545,31 +545,13 @@ class SegWitTest(BitcoinTestFramework):
 
     @subtest
     def test_getblocktemplate_before_lockin(self):
-        # Node0 is segwit aware, node2 is not.
-        for node in [self.nodes[0], self.nodes[2]]:
-            gbt_results = node.getblocktemplate()
-            block_version = gbt_results['version']
-            # If we're not indicating segwit support, we will still be
-            # signalling for segwit activation.
-            assert_equal((block_version & (1 << VB_WITNESS_BIT) != 0), node == self.nodes[0])
-            # If we don't specify the segwit rule, then we won't get a default
-            # commitment.
-            assert('default_witness_commitment' not in gbt_results)
-
-        # Workaround:
-        # Can either change the tip, or change the mempool and wait 5 seconds
-        # to trigger a recomputation of getblocktemplate.
         txid = int(self.nodes[0].sendtoaddress(self.nodes[0].getnewaddress(), 1), 16)
-        # Using mocktime lets us avoid sleep()
-        sync_mempools(self.nodes)
-        self.nodes[0].setmocktime(int(time.time()) + 10)
-        self.nodes[2].setmocktime(int(time.time()) + 10)
 
         for node in [self.nodes[0], self.nodes[2]]:
             gbt_results = node.getblocktemplate({"rules": ["segwit"]})
             block_version = gbt_results['version']
             if node == self.nodes[2]:
-                # If this is a non-segwit node, we should still not get a witness
+                # If this is a non-segwit node, we should not get a witness
                 # commitment, nor a version bit signalling segwit.
                 assert_equal(block_version & (1 << VB_WITNESS_BIT), 0)
                 assert('default_witness_commitment' not in gbt_results)
@@ -586,10 +568,6 @@ class SegWitTest(BitcoinTestFramework):
                 script = get_witness_script(witness_root, 0)
                 assert_equal(witness_commitment, bytes_to_hex_str(script))
 
-        # undo mocktime
-        self.nodes[0].setmocktime(0)
-        self.nodes[2].setmocktime(0)
-
     @subtest
     def advance_to_segwit_lockin(self):
         """Mine enough blocks to lock in segwit, but don't activate."""