1 files changed, 117 insertions, 0 deletions
diff --git a/test/functional/p2p_invalid_block.py b/test/functional/p2p_invalid_block.py
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+++ b/test/functional/p2p_invalid_block.py
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+#!/usr/bin/env python3
+# Copyright (c) 2015-2017 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 node responses to invalid blocks.
+
+In this test we connect to one node over p2p, and test block requests:
+1) Valid blocks should be requested and become chain tip.
+2) Invalid block with duplicated transaction should be re-requested.
+3) Invalid block with bad coinbase value should be rejected and not
+re-requested.
+"""
+
+from test_framework.test_framework import ComparisonTestFramework
+from test_framework.util import *
+from test_framework.comptool import TestManager, TestInstance, RejectResult
+from test_framework.blocktools import *
+from test_framework.mininode import network_thread_start
+import copy
+import time
+
+# Use the ComparisonTestFramework with 1 node: only use --testbinary.
+class InvalidBlockRequestTest(ComparisonTestFramework):
+
+    ''' Can either run this test as 1 node with expected answers, or two and compare them. 
+        Change the "outcome" variable from each TestInstance object to only do the comparison. '''
+    def set_test_params(self):
+        self.num_nodes = 1
+        self.setup_clean_chain = True
+
+    def run_test(self):
+        test = TestManager(self, self.options.tmpdir)
+        test.add_all_connections(self.nodes)
+        self.tip = None
+        self.block_time = None
+        network_thread_start()
+        test.run()
+
+    def get_tests(self):
+        if self.tip is None:
+            self.tip = int("0x" + self.nodes[0].getbestblockhash(), 0)
+        self.block_time = int(time.time())+1
+
+        '''
+        Create a new block with an anyone-can-spend coinbase
+        '''
+        height = 1
+        block = create_block(self.tip, create_coinbase(height), self.block_time)
+        self.block_time += 1
+        block.solve()
+        # Save the coinbase for later
+        self.block1 = block
+        self.tip = block.sha256
+        height += 1
+        yield TestInstance([[block, True]])
+
+        '''
+        Now we need that block to mature so we can spend the coinbase.
+        '''
+        test = TestInstance(sync_every_block=False)
+        for i in range(100):
+            block = create_block(self.tip, create_coinbase(height), self.block_time)
+            block.solve()
+            self.tip = block.sha256
+            self.block_time += 1
+            test.blocks_and_transactions.append([block, True])
+            height += 1
+        yield test
+
+        '''
+        Now we use merkle-root malleability to generate an invalid block with
+        same blockheader.
+        Manufacture a block with 3 transactions (coinbase, spend of prior
+        coinbase, spend of that spend).  Duplicate the 3rd transaction to 
+        leave merkle root and blockheader unchanged but invalidate the block.
+        '''
+        block2 = create_block(self.tip, create_coinbase(height), self.block_time)
+        self.block_time += 1
+
+        # b'0x51' is OP_TRUE
+        tx1 = create_transaction(self.block1.vtx[0], 0, b'\x51', 50 * COIN)
+        tx2 = create_transaction(tx1, 0, b'\x51', 50 * COIN)
+
+        block2.vtx.extend([tx1, tx2])
+        block2.hashMerkleRoot = block2.calc_merkle_root()
+        block2.rehash()
+        block2.solve()
+        orig_hash = block2.sha256
+        block2_orig = copy.deepcopy(block2)
+
+        # Mutate block 2
+        block2.vtx.append(tx2)
+        assert_equal(block2.hashMerkleRoot, block2.calc_merkle_root())
+        assert_equal(orig_hash, block2.rehash())
+        assert(block2_orig.vtx != block2.vtx)
+
+        self.tip = block2.sha256
+        yield TestInstance([[block2, RejectResult(16, b'bad-txns-duplicate')], [block2_orig, True]])
+        height += 1
+
+        '''
+        Make sure that a totally screwed up block is not valid.
+        '''
+        block3 = create_block(self.tip, create_coinbase(height), self.block_time)
+        self.block_time += 1
+        block3.vtx[0].vout[0].nValue = 100 * COIN # Too high!
+        block3.vtx[0].sha256=None
+        block3.vtx[0].calc_sha256()
+        block3.hashMerkleRoot = block3.calc_merkle_root()
+        block3.rehash()
+        block3.solve()
+
+        yield TestInstance([[block3, RejectResult(16, b'bad-cb-amount')]])
+
+
+if __name__ == '__main__':
+    InvalidBlockRequestTest().main()