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Use best header chain timestamps to detect partitioning

The partition checking code was using chainActive timestamps
to detect partitioning; with headers-first syncing, it should use
(and with this pull request, does use) pIndexBestHeader timestamps.

Fixes issue #6251
tags/v0.15.1
Gavin Andresen 5 years ago
parent
commit
65b9454503
No account linked to committer's email address
4 changed files with 16 additions and 14 deletions
  1. 1
    1
      src/init.cpp
  2. 10
    6
      src/main.cpp
  3. 1
    1
      src/main.h
  4. 4
    6
      src/test/alert_tests.cpp

+ 1
- 1
src/init.cpp View File

@@ -1396,7 +1396,7 @@ bool AppInit2(boost::thread_group& threadGroup, CScheduler& scheduler)
// Monitor the chain, and alert if we get blocks much quicker or slower than expected
int64_t nPowTargetSpacing = Params().GetConsensus().nPowTargetSpacing;
CScheduler::Function f = boost::bind(&PartitionCheck, &IsInitialBlockDownload,
boost::ref(cs_main), boost::cref(chainActive), nPowTargetSpacing);
boost::ref(cs_main), boost::cref(pindexBestHeader), nPowTargetSpacing);
scheduler.scheduleEvery(f, nPowTargetSpacing);

#ifdef ENABLE_WALLET

+ 10
- 6
src/main.cpp View File

@@ -1711,9 +1711,10 @@ void ThreadScriptCheck() {
// we're being fed a bad chain (blocks being generated much
// too slowly or too quickly).
//
void PartitionCheck(bool (*initialDownloadCheck)(), CCriticalSection& cs, const CChain& chain, int64_t nPowTargetSpacing)
void PartitionCheck(bool (*initialDownloadCheck)(), CCriticalSection& cs, const CBlockIndex *const &bestHeader,
int64_t nPowTargetSpacing)
{
if (initialDownloadCheck()) return;
if (bestHeader == NULL || initialDownloadCheck()) return;

static int64_t lastAlertTime = 0;
int64_t now = GetAdjustedTime();
@@ -1729,10 +1730,13 @@ void PartitionCheck(bool (*initialDownloadCheck)(), CCriticalSection& cs, const
int64_t startTime = GetAdjustedTime()-SPAN_SECONDS;

LOCK(cs);
int h = chain.Height();
while (h > 0 && chain[h]->GetBlockTime() >= startTime)
--h;
int nBlocks = chain.Height()-h;
const CBlockIndex* i = bestHeader;
int nBlocks = 0;
while (i->GetBlockTime() >= startTime) {
++nBlocks;
i = i->pprev;
if (i == NULL) return; // Ran out of chain, we must not be fully sync'ed
}

// How likely is it to find that many by chance?
double p = boost::math::pdf(poisson, nBlocks);

+ 1
- 1
src/main.h View File

@@ -186,7 +186,7 @@ bool SendMessages(CNode* pto, bool fSendTrickle);
/** Run an instance of the script checking thread */
void ThreadScriptCheck();
/** Try to detect Partition (network isolation) attacks against us */
void PartitionCheck(bool (*initialDownloadCheck)(), CCriticalSection& cs, const CChain& chain, int64_t nPowTargetSpacing);
void PartitionCheck(bool (*initialDownloadCheck)(), CCriticalSection& cs, const CBlockIndex *const &bestHeader, int64_t nPowTargetSpacing);
/** Check whether we are doing an initial block download (synchronizing from disk or network) */
bool IsInitialBlockDownload();
/** Format a string that describes several potential problems detected by the core */

+ 4
- 6
src/test/alert_tests.cpp View File

@@ -201,7 +201,6 @@ BOOST_AUTO_TEST_CASE(PartitionAlert)
{
// Test PartitionCheck
CCriticalSection csDummy;
CChain chainDummy;
CBlockIndex indexDummy[100];
CChainParams& params = Params(CBaseChainParams::MAIN);
int64_t nPowTargetSpacing = params.GetConsensus().nPowTargetSpacing;
@@ -220,17 +219,16 @@ BOOST_AUTO_TEST_CASE(PartitionAlert)
// Other members don't matter, the partition check code doesn't
// use them
}
chainDummy.SetTip(&indexDummy[99]);

// Test 1: chain with blocks every nPowTargetSpacing seconds,
// as normal, no worries:
PartitionCheck(falseFunc, csDummy, chainDummy, nPowTargetSpacing);
PartitionCheck(falseFunc, csDummy, &indexDummy[99], nPowTargetSpacing);
BOOST_CHECK(strMiscWarning.empty());

// Test 2: go 3.5 hours without a block, expect a warning:
now += 3*60*60+30*60;
SetMockTime(now);
PartitionCheck(falseFunc, csDummy, chainDummy, nPowTargetSpacing);
PartitionCheck(falseFunc, csDummy, &indexDummy[99], nPowTargetSpacing);
BOOST_CHECK(!strMiscWarning.empty());
BOOST_TEST_MESSAGE(std::string("Got alert text: ")+strMiscWarning);
strMiscWarning = "";
@@ -239,7 +237,7 @@ BOOST_AUTO_TEST_CASE(PartitionAlert)
// code:
now += 60*10;
SetMockTime(now);
PartitionCheck(falseFunc, csDummy, chainDummy, nPowTargetSpacing);
PartitionCheck(falseFunc, csDummy, &indexDummy[99], nPowTargetSpacing);
BOOST_CHECK(strMiscWarning.empty());

// Test 4: get 2.5 times as many blocks as expected:
@@ -248,7 +246,7 @@ BOOST_AUTO_TEST_CASE(PartitionAlert)
int64_t quickSpacing = nPowTargetSpacing*2/5;
for (int i = 0; i < 100; i++) // Tweak chain timestamps:
indexDummy[i].nTime = now - (100-i)*quickSpacing;
PartitionCheck(falseFunc, csDummy, chainDummy, nPowTargetSpacing);
PartitionCheck(falseFunc, csDummy, &indexDummy[99], nPowTargetSpacing);
BOOST_CHECK(!strMiscWarning.empty());
BOOST_TEST_MESSAGE(std::string("Got alert text: ")+strMiscWarning);
strMiscWarning = "";

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