diff options
Diffstat (limited to 'src/cryptonote_core')
-rw-r--r-- | src/cryptonote_core/blockchain.cpp | 115 | ||||
-rw-r--r-- | src/cryptonote_core/blockchain.h | 16 | ||||
-rw-r--r-- | src/cryptonote_core/cryptonote_core.cpp | 7 | ||||
-rw-r--r-- | src/cryptonote_core/cryptonote_core.h | 8 |
4 files changed, 146 insertions, 0 deletions
diff --git a/src/cryptonote_core/blockchain.cpp b/src/cryptonote_core/blockchain.cpp index fb2c71a3a..cad4620d2 100644 --- a/src/cryptonote_core/blockchain.cpp +++ b/src/cryptonote_core/blockchain.cpp @@ -32,6 +32,7 @@ #include <cstdio> #include <boost/filesystem.hpp> #include <boost/range/adaptor/reversed.hpp> +#include <boost/format.hpp> #include "include_base_utils.h" #include "cryptonote_basic/cryptonote_basic_impl.h" @@ -439,6 +440,15 @@ bool Blockchain::init(BlockchainDB* db, const network_type nettype, bool offline m_long_term_block_weights_cache_rolling_median = epee::misc_utils::rolling_median_t<uint64_t>(m_long_term_block_weights_window); } + bool difficulty_ok; + uint64_t difficulty_recalc_height; + std::tie(difficulty_ok, difficulty_recalc_height) = check_difficulty_checkpoints(); + if (!difficulty_ok) + { + MERROR("Difficulty drift detected!"); + recalculate_difficulties(difficulty_recalc_height); + } + { db_txn_guard txn_guard(m_db, m_db->is_read_only()); if (!update_next_cumulative_weight_limit()) @@ -888,6 +898,111 @@ difficulty_type Blockchain::get_difficulty_for_next_block() return diff; } //------------------------------------------------------------------ +std::pair<bool, uint64_t> Blockchain::check_difficulty_checkpoints() const +{ + uint64_t res = 0; + for (const std::pair<uint64_t, difficulty_type>& i : m_checkpoints.get_difficulty_points()) + { + if (i.first >= m_db->height()) + break; + if (m_db->get_block_cumulative_difficulty(i.first) != i.second) + return {false, res}; + res = i.first; + } + return {true, res}; +} +//------------------------------------------------------------------ +size_t Blockchain::recalculate_difficulties(boost::optional<uint64_t> start_height_opt) +{ + if (m_fixed_difficulty) + { + return 0; + } + LOG_PRINT_L3("Blockchain::" << __func__); + CRITICAL_REGION_LOCAL(m_blockchain_lock); + + const uint64_t start_height = start_height_opt ? *start_height_opt : check_difficulty_checkpoints().second; + const uint64_t top_height = m_db->height() - 1; + MGINFO("Recalculating difficulties from height " << start_height << " to height " << top_height); + + std::vector<uint64_t> timestamps; + std::vector<difficulty_type> difficulties; + timestamps.reserve(DIFFICULTY_BLOCKS_COUNT + 1); + difficulties.reserve(DIFFICULTY_BLOCKS_COUNT + 1); + if (start_height > 1) + { + for (uint64_t i = 0; i < DIFFICULTY_BLOCKS_COUNT; ++i) + { + uint64_t height = start_height - 1 - i; + if (height == 0) + break; + timestamps.insert(timestamps.begin(), m_db->get_block_timestamp(height)); + difficulties.insert(difficulties.begin(), m_db->get_block_cumulative_difficulty(height)); + } + } + difficulty_type last_cum_diff = start_height <= 1 ? start_height : difficulties.back(); + uint64_t drift_start_height = 0; + std::vector<difficulty_type> new_cumulative_difficulties; + for (uint64_t height = start_height; height <= top_height; ++height) + { + size_t target = get_ideal_hard_fork_version(height) < 2 ? DIFFICULTY_TARGET_V1 : DIFFICULTY_TARGET_V2; + difficulty_type recalculated_diff = next_difficulty(timestamps, difficulties, target); + + boost::multiprecision::uint256_t recalculated_cum_diff_256 = boost::multiprecision::uint256_t(recalculated_diff) + last_cum_diff; + CHECK_AND_ASSERT_THROW_MES(recalculated_cum_diff_256 <= std::numeric_limits<difficulty_type>::max(), "Difficulty overflow!"); + difficulty_type recalculated_cum_diff = recalculated_cum_diff_256.convert_to<difficulty_type>(); + + if (drift_start_height == 0) + { + difficulty_type existing_cum_diff = m_db->get_block_cumulative_difficulty(height); + if (recalculated_cum_diff != existing_cum_diff) + { + drift_start_height = height; + new_cumulative_difficulties.reserve(top_height + 1 - height); + LOG_ERROR("Difficulty drift found at height:" << height << ", hash:" << m_db->get_block_hash_from_height(height) << ", existing:" << existing_cum_diff << ", recalculated:" << recalculated_cum_diff); + } + } + if (drift_start_height > 0) + { + new_cumulative_difficulties.push_back(recalculated_cum_diff); + if (height % 100000 == 0) + LOG_ERROR(boost::format("%llu / %llu (%.1f%%)") % height % top_height % (100 * (height - drift_start_height) / float(top_height - drift_start_height))); + } + + if (height > 0) + { + timestamps.push_back(m_db->get_block_timestamp(height)); + difficulties.push_back(recalculated_cum_diff); + } + if (timestamps.size() > DIFFICULTY_BLOCKS_COUNT) + { + CHECK_AND_ASSERT_THROW_MES(timestamps.size() == DIFFICULTY_BLOCKS_COUNT + 1, "Wrong timestamps size: " << timestamps.size()); + timestamps.erase(timestamps.begin()); + difficulties.erase(difficulties.begin()); + } + last_cum_diff = recalculated_cum_diff; + } + + if (drift_start_height > 0) + { + LOG_ERROR("Writing to the DB..."); + try + { + m_db->correct_block_cumulative_difficulties(drift_start_height, new_cumulative_difficulties); + } + catch (const std::exception& e) + { + LOG_ERROR("Error correcting cumulative difficulties from height " << drift_start_height << ", what = " << e.what()); + } + LOG_ERROR("Corrected difficulties for " << new_cumulative_difficulties.size() << " blocks"); + // clear cache + m_difficulty_for_next_block_top_hash = crypto::null_hash; + m_timestamps_and_difficulties_height = 0; + } + + return new_cumulative_difficulties.size(); +} +//------------------------------------------------------------------ std::vector<time_t> Blockchain::get_last_block_timestamps(unsigned int blocks) const { uint64_t height = m_db->height(); diff --git a/src/cryptonote_core/blockchain.h b/src/cryptonote_core/blockchain.h index 3a89cc5df..4dc2cea31 100644 --- a/src/cryptonote_core/blockchain.h +++ b/src/cryptonote_core/blockchain.h @@ -310,6 +310,22 @@ namespace cryptonote difficulty_type get_difficulty_for_next_block(); /** + * @brief check currently stored difficulties against difficulty checkpoints + * + * @return {flag, height} flag: true if all difficulty checkpoints pass, height: the last checkpoint height before the difficulty drift bug starts + */ + std::pair<bool, uint64_t> check_difficulty_checkpoints() const; + + /** + * @brief recalculate difficulties for blocks after the last difficulty checkpoints to circumvent the annoying 'difficulty drift' bug + * + * @param start_height: if omitted, starts recalculation from the last difficulty checkpoint + * + * @return number of blocks whose difficulties got corrected + */ + size_t recalculate_difficulties(boost::optional<uint64_t> start_height = boost::none); + + /** * @brief adds a block to the blockchain * * Adds a new block to the blockchain. If the block's parent is not the diff --git a/src/cryptonote_core/cryptonote_core.cpp b/src/cryptonote_core/cryptonote_core.cpp index 0f8bde3e9..5e4a1accd 100644 --- a/src/cryptonote_core/cryptonote_core.cpp +++ b/src/cryptonote_core/cryptonote_core.cpp @@ -1662,6 +1662,7 @@ namespace cryptonote m_check_disk_space_interval.do_call(boost::bind(&core::check_disk_space, this)); m_block_rate_interval.do_call(boost::bind(&core::check_block_rate, this)); m_blockchain_pruning_interval.do_call(boost::bind(&core::update_blockchain_pruning, this)); + m_diff_recalc_interval.do_call(boost::bind(&core::recalculate_difficulties, this)); m_miner.on_idle(); m_mempool.on_idle(); return true; @@ -1923,6 +1924,12 @@ namespace cryptonote return true; } //----------------------------------------------------------------------------------------------- + bool core::recalculate_difficulties() + { + m_blockchain_storage.recalculate_difficulties(); + return true; + } + //----------------------------------------------------------------------------------------------- void core::flush_bad_txs_cache() { bad_semantics_txes_lock.lock(); diff --git a/src/cryptonote_core/cryptonote_core.h b/src/cryptonote_core/cryptonote_core.h index 988f25ceb..5cbec7d62 100644 --- a/src/cryptonote_core/cryptonote_core.h +++ b/src/cryptonote_core/cryptonote_core.h @@ -1040,6 +1040,13 @@ namespace cryptonote */ bool check_block_rate(); + /** + * @brief recalculate difficulties after the last difficulty checklpoint to circumvent the annoying 'difficulty drift' bug + * + * @return true + */ + bool recalculate_difficulties(); + bool m_test_drop_download = true; //!< whether or not to drop incoming blocks (for testing) uint64_t m_test_drop_download_height = 0; //!< height under which to drop incoming blocks, if doing so @@ -1065,6 +1072,7 @@ namespace cryptonote epee::math_helper::once_a_time_seconds<60*10, true> m_check_disk_space_interval; //!< interval for checking for disk space epee::math_helper::once_a_time_seconds<90, false> m_block_rate_interval; //!< interval for checking block rate epee::math_helper::once_a_time_seconds<60*60*5, true> m_blockchain_pruning_interval; //!< interval for incremental blockchain pruning + epee::math_helper::once_a_time_seconds<60*60*24*7, false> m_diff_recalc_interval; //!< interval for recalculating difficulties std::atomic<bool> m_starter_message_showed; //!< has the "daemon will sync now" message been shown? |