From ab8be98fdb25b678a8cd7e89adf06d1b1f6bdd62 Mon Sep 17 00:00:00 2001 From: BtcDrak Date: Tue, 14 Jun 2016 12:26:59 +0100 Subject: Remove bad chain alert partition check As per meeting 2016-03-31 https://bitcoincore.org/en/meetings/2016/03/31/#bad-chain-alerts The partition checker was producing huge number of false-positives and was disabled in 0.12.1 on the understanding it would either be fixed in 0.13 or removed entirely from master if not. --- src/Makefile.test.include | 1 - src/init.cpp | 6 ---- src/main.cpp | 62 ------------------------------------- src/main.h | 2 -- src/test/alert_tests.cpp | 79 ----------------------------------------------- 5 files changed, 150 deletions(-) delete mode 100644 src/test/alert_tests.cpp diff --git a/src/Makefile.test.include b/src/Makefile.test.include index 41d811fb54..0b6f306f83 100644 --- a/src/Makefile.test.include +++ b/src/Makefile.test.include @@ -38,7 +38,6 @@ BITCOIN_TESTS =\ test/arith_uint256_tests.cpp \ test/scriptnum10.h \ test/addrman_tests.cpp \ - test/alert_tests.cpp \ test/amount_tests.cpp \ test/allocator_tests.cpp \ test/base32_tests.cpp \ diff --git a/src/init.cpp b/src/init.cpp index c2ba9ae44b..323d1cedcf 100644 --- a/src/init.cpp +++ b/src/init.cpp @@ -1416,12 +1416,6 @@ bool AppInit2(boost::thread_group& threadGroup, CScheduler& scheduler) StartNode(threadGroup, 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(pindexBestHeader), nPowTargetSpacing); - scheduler.scheduleEvery(f, nPowTargetSpacing); - // ********************************************************* Step 12: finished SetRPCWarmupFinished(); diff --git a/src/main.cpp b/src/main.cpp index 62012bf567..91da3f47a5 100644 --- a/src/main.cpp +++ b/src/main.cpp @@ -2118,68 +2118,6 @@ void ThreadScriptCheck() { scriptcheckqueue.Thread(); } -// -// Called periodically asynchronously; alerts if it smells like -// we're being fed a bad chain (blocks being generated much -// too slowly or too quickly). -// -void PartitionCheck(bool (*initialDownloadCheck)(), CCriticalSection& cs, const CBlockIndex *const &bestHeader, - int64_t nPowTargetSpacing) -{ - if (bestHeader == NULL || initialDownloadCheck()) return; - - static int64_t lastAlertTime = 0; - int64_t now = GetAdjustedTime(); - if (lastAlertTime > now-60*60*24) return; // Alert at most once per day - - const int SPAN_HOURS=4; - const int SPAN_SECONDS=SPAN_HOURS*60*60; - int BLOCKS_EXPECTED = SPAN_SECONDS / nPowTargetSpacing; - - boost::math::poisson_distribution poisson(BLOCKS_EXPECTED); - - std::string strWarning; - int64_t startTime = GetAdjustedTime()-SPAN_SECONDS; - - LOCK(cs); - 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); - - LogPrint("partitioncheck", "%s: Found %d blocks in the last %d hours\n", __func__, nBlocks, SPAN_HOURS); - LogPrint("partitioncheck", "%s: likelihood: %g\n", __func__, p); - - // Aim for one false-positive about every fifty years of normal running: - const int FIFTY_YEARS = 50*365*24*60*60; - double alertThreshold = 1.0 / (FIFTY_YEARS / SPAN_SECONDS); - - if (p <= alertThreshold && nBlocks < BLOCKS_EXPECTED) - { - // Many fewer blocks than expected: alert! - strWarning = strprintf(_("WARNING: check your network connection, %d blocks received in the last %d hours (%d expected)"), - nBlocks, SPAN_HOURS, BLOCKS_EXPECTED); - } - else if (p <= alertThreshold && nBlocks > BLOCKS_EXPECTED) - { - // Many more blocks than expected: alert! - strWarning = strprintf(_("WARNING: abnormally high number of blocks generated, %d blocks received in the last %d hours (%d expected)"), - nBlocks, SPAN_HOURS, BLOCKS_EXPECTED); - } - if (!strWarning.empty()) - { - strMiscWarning = strWarning; - AlertNotify(strWarning); - lastAlertTime = now; - } -} - // Protected by cs_main VersionBitsCache versionbitscache; diff --git a/src/main.h b/src/main.h index 9b99ae7c87..05f7d4d920 100644 --- a/src/main.h +++ b/src/main.h @@ -242,8 +242,6 @@ bool ProcessMessages(CNode* pfrom); bool SendMessages(CNode* pto); /** 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 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. diff --git a/src/test/alert_tests.cpp b/src/test/alert_tests.cpp deleted file mode 100644 index 70f1f12273..0000000000 --- a/src/test/alert_tests.cpp +++ /dev/null @@ -1,79 +0,0 @@ -// Copyright (c) 2013-2015 The Bitcoin Core developers -// Distributed under the MIT software license, see the accompanying -// file COPYING or http://www.opensource.org/licenses/mit-license.php. - -// Unit tests for alert system - -#include "chainparams.h" -#include "main.h" // For PartitionCheck - -#include "test/testutil.h" -#include "test/test_bitcoin.h" - -#include - -BOOST_FIXTURE_TEST_SUITE(Alert_tests, TestingSetup) - - -static bool falseFunc() { return false; } - -BOOST_AUTO_TEST_CASE(PartitionAlert) -{ - // Test PartitionCheck - CCriticalSection csDummy; - CBlockIndex indexDummy[100]; - CChainParams& params = Params(CBaseChainParams::MAIN); - int64_t nPowTargetSpacing = params.GetConsensus().nPowTargetSpacing; - - // Generate fake blockchain timestamps relative to - // an arbitrary time: - int64_t now = 1427379054; - SetMockTime(now); - for (int i = 0; i < 100; i++) - { - indexDummy[i].phashBlock = NULL; - if (i == 0) indexDummy[i].pprev = NULL; - else indexDummy[i].pprev = &indexDummy[i-1]; - indexDummy[i].nHeight = i; - indexDummy[i].nTime = now - (100-i)*nPowTargetSpacing; - // Other members don't matter, the partition check code doesn't - // use them - } - - strMiscWarning = ""; - - // Test 1: chain with blocks every nPowTargetSpacing seconds, - // as normal, no worries: - PartitionCheck(falseFunc, csDummy, &indexDummy[99], nPowTargetSpacing); - BOOST_CHECK_MESSAGE(strMiscWarning.empty(), strMiscWarning); - - // Test 2: go 3.5 hours without a block, expect a warning: - now += 3*60*60+30*60; - SetMockTime(now); - PartitionCheck(falseFunc, csDummy, &indexDummy[99], nPowTargetSpacing); - BOOST_CHECK(!strMiscWarning.empty()); - BOOST_TEST_MESSAGE(std::string("Got alert text: ")+strMiscWarning); - strMiscWarning = ""; - - // Test 3: test the "partition alerts only go off once per day" - // code: - now += 60*10; - SetMockTime(now); - PartitionCheck(falseFunc, csDummy, &indexDummy[99], nPowTargetSpacing); - BOOST_CHECK(strMiscWarning.empty()); - - // Test 4: get 2.5 times as many blocks as expected: - now += 60*60*24; // Pretend it is a day later - SetMockTime(now); - 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, &indexDummy[99], nPowTargetSpacing); - BOOST_CHECK(!strMiscWarning.empty()); - BOOST_TEST_MESSAGE(std::string("Got alert text: ")+strMiscWarning); - strMiscWarning = ""; - - SetMockTime(0); -} - -BOOST_AUTO_TEST_SUITE_END() \ No newline at end of file -- cgit v1.2.3