1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
|
// Copyright (c) 2022 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#include <chain.h>
#include <chainparams.h>
#include <consensus/params.h>
#include <headerssync.h>
#include <pow.h>
#include <test/util/setup_common.h>
#include <validation.h>
#include <vector>
#include <boost/test/unit_test.hpp>
struct HeadersGeneratorSetup : public RegTestingSetup {
/** Search for a nonce to meet (regtest) proof of work */
void FindProofOfWork(CBlockHeader& starting_header);
/**
* Generate headers in a chain that build off a given starting hash, using
* the given nVersion, advancing time by 1 second from the starting
* prev_time, and with a fixed merkle root hash.
*/
void GenerateHeaders(std::vector<CBlockHeader>& headers, size_t count,
const uint256& starting_hash, const int nVersion, int prev_time,
const uint256& merkle_root, const uint32_t nBits);
};
void HeadersGeneratorSetup::FindProofOfWork(CBlockHeader& starting_header)
{
while (!CheckProofOfWork(starting_header.GetHash(), starting_header.nBits, Params().GetConsensus())) {
++(starting_header.nNonce);
}
}
void HeadersGeneratorSetup::GenerateHeaders(std::vector<CBlockHeader>& headers,
size_t count, const uint256& starting_hash, const int nVersion, int prev_time,
const uint256& merkle_root, const uint32_t nBits)
{
uint256 prev_hash = starting_hash;
while (headers.size() < count) {
headers.emplace_back();
CBlockHeader& next_header = headers.back();;
next_header.nVersion = nVersion;
next_header.hashPrevBlock = prev_hash;
next_header.hashMerkleRoot = merkle_root;
next_header.nTime = prev_time+1;
next_header.nBits = nBits;
FindProofOfWork(next_header);
prev_hash = next_header.GetHash();
prev_time = next_header.nTime;
}
return;
}
BOOST_FIXTURE_TEST_SUITE(headers_sync_chainwork_tests, HeadersGeneratorSetup)
// In this test, we construct two sets of headers from genesis, one with
// sufficient proof of work and one without.
// 1. We deliver the first set of headers and verify that the headers sync state
// updates to the REDOWNLOAD phase successfully.
// 2. Then we deliver the second set of headers and verify that they fail
// processing (presumably due to commitments not matching).
// 3. Finally, we verify that repeating with the first set of headers in both
// phases is successful.
BOOST_AUTO_TEST_CASE(headers_sync_state)
{
std::vector<CBlockHeader> first_chain;
std::vector<CBlockHeader> second_chain;
std::unique_ptr<HeadersSyncState> hss;
const int target_blocks = 15000;
arith_uint256 chain_work = target_blocks*2;
// Generate headers for two different chains (using differing merkle roots
// to ensure the headers are different).
GenerateHeaders(first_chain, target_blocks-1, Params().GenesisBlock().GetHash(),
Params().GenesisBlock().nVersion, Params().GenesisBlock().nTime,
ArithToUint256(0), Params().GenesisBlock().nBits);
GenerateHeaders(second_chain, target_blocks-2, Params().GenesisBlock().GetHash(),
Params().GenesisBlock().nVersion, Params().GenesisBlock().nTime,
ArithToUint256(1), Params().GenesisBlock().nBits);
const CBlockIndex* chain_start = WITH_LOCK(::cs_main, return m_node.chainman->m_blockman.LookupBlockIndex(Params().GenesisBlock().GetHash()));
std::vector<CBlockHeader> headers_batch;
// Feed the first chain to HeadersSyncState, by delivering 1 header
// initially and then the rest.
headers_batch.insert(headers_batch.end(), std::next(first_chain.begin()), first_chain.end());
hss.reset(new HeadersSyncState(0, Params().GetConsensus(), chain_start, chain_work));
(void)hss->ProcessNextHeaders({first_chain.front()}, true);
// Pretend the first header is still "full", so we don't abort.
auto result = hss->ProcessNextHeaders(headers_batch, true);
// This chain should look valid, and we should have met the proof-of-work
// requirement.
BOOST_CHECK(result.success);
BOOST_CHECK(result.request_more);
BOOST_CHECK(hss->GetState() == HeadersSyncState::State::REDOWNLOAD);
// Try to sneakily feed back the second chain.
result = hss->ProcessNextHeaders(second_chain, true);
BOOST_CHECK(!result.success); // foiled!
BOOST_CHECK(hss->GetState() == HeadersSyncState::State::FINAL);
// Now try again, this time feeding the first chain twice.
hss.reset(new HeadersSyncState(0, Params().GetConsensus(), chain_start, chain_work));
(void)hss->ProcessNextHeaders(first_chain, true);
BOOST_CHECK(hss->GetState() == HeadersSyncState::State::REDOWNLOAD);
result = hss->ProcessNextHeaders(first_chain, true);
BOOST_CHECK(result.success);
BOOST_CHECK(!result.request_more);
// All headers should be ready for acceptance:
BOOST_CHECK(result.pow_validated_headers.size() == first_chain.size());
// Nothing left for the sync logic to do:
BOOST_CHECK(hss->GetState() == HeadersSyncState::State::FINAL);
// Finally, verify that just trying to process the second chain would not
// succeed (too little work)
hss.reset(new HeadersSyncState(0, Params().GetConsensus(), chain_start, chain_work));
BOOST_CHECK(hss->GetState() == HeadersSyncState::State::PRESYNC);
// Pretend just the first message is "full", so we don't abort.
(void)hss->ProcessNextHeaders({second_chain.front()}, true);
BOOST_CHECK(hss->GetState() == HeadersSyncState::State::PRESYNC);
headers_batch.clear();
headers_batch.insert(headers_batch.end(), std::next(second_chain.begin(), 1), second_chain.end());
// Tell the sync logic that the headers message was not full, implying no
// more headers can be requested. For a low-work-chain, this should causes
// the sync to end with no headers for acceptance.
result = hss->ProcessNextHeaders(headers_batch, false);
BOOST_CHECK(hss->GetState() == HeadersSyncState::State::FINAL);
BOOST_CHECK(result.pow_validated_headers.empty());
BOOST_CHECK(!result.request_more);
// Nevertheless, no validation errors should have been detected with the
// chain:
BOOST_CHECK(result.success);
}
BOOST_AUTO_TEST_SUITE_END()
|